diff options
| author | Vincent Mailhol <mailhol.vincent@wanadoo.fr> | 2021-04-10 12:59:46 +0300 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2021-04-13 11:15:42 +0300 |
| commit | 8537257874e949a59c834cecfd5a063e11b64b0b (patch) | |
| tree | 2e9d107eaf1d562f403c47e52fcff03bbf27d0a6 | |
| parent | cfa00070a1a82fce8c0ad3327fad1f182d4c691f (diff) | |
| download | linux-8537257874e949a59c834cecfd5a063e11b64b0b.tar.xz | |
can: etas_es58x: add core support for ETAS ES58X CAN USB interfaces
This patch adds the core support for various USB CAN interfaces from
ETAS GmbH (https://www.etas.com/en/products/es58x.php). The next
patches add the glue code drivers for the individual interfaces.
Link: https://lore.kernel.org/r/20210410095948.233305-2-mailhol.vincent@wanadoo.fr
Co-developed-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Signed-off-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | drivers/net/can/usb/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/net/can/usb/Makefile | 1 | ||||
| -rw-r--r-- | drivers/net/can/usb/etas_es58x/Makefile | 3 | ||||
| -rw-r--r-- | drivers/net/can/usb/etas_es58x/es58x_core.c | 2281 | ||||
| -rw-r--r-- | drivers/net/can/usb/etas_es58x/es58x_core.h | 693 |
5 files changed, 2988 insertions, 0 deletions
diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig index 538f4d9adb91..3deb9f1cd292 100644 --- a/drivers/net/can/usb/Kconfig +++ b/drivers/net/can/usb/Kconfig @@ -20,6 +20,16 @@ config CAN_ESD_USB2 This driver supports the CAN-USB/2 interface from esd electronic system design gmbh (http://www.esd.eu). +config CAN_ETAS_ES58X + tristate "ETAS ES58X CAN/USB interfaces" + select CRC16 + help + This driver supports the ES581.4, ES582.1 and ES584.1 interfaces + from ETAS GmbH (https://www.etas.com/en/products/es58x.php). + + To compile this driver as a module, choose M here: the module + will be called etas_es58x. + config CAN_GS_USB tristate "Geschwister Schneider UG interfaces" help diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile index aa0f17c0b2ed..748cf31a0d53 100644 --- a/drivers/net/can/usb/Makefile +++ b/drivers/net/can/usb/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_CAN_8DEV_USB) += usb_8dev.o obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o obj-$(CONFIG_CAN_ESD_USB2) += esd_usb2.o +obj-$(CONFIG_CAN_ETAS_ES58X) += etas_es58x/ obj-$(CONFIG_CAN_GS_USB) += gs_usb.o obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb/ obj-$(CONFIG_CAN_MCBA_USB) += mcba_usb.o diff --git a/drivers/net/can/usb/etas_es58x/Makefile b/drivers/net/can/usb/etas_es58x/Makefile new file mode 100644 index 000000000000..60a1ac935a69 --- /dev/null +++ b/drivers/net/can/usb/etas_es58x/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_CAN_ETAS_ES58X) += etas_es58x.o +etas_es58x-y = es58x_core.o diff --git a/drivers/net/can/usb/etas_es58x/es58x_core.c b/drivers/net/can/usb/etas_es58x/es58x_core.c new file mode 100644 index 000000000000..da7f9d1d1162 --- /dev/null +++ b/drivers/net/can/usb/etas_es58x/es58x_core.c @@ -0,0 +1,2281 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces. + * + * File es58x_core.c: Core logic to manage the network devices and the + * USB interface. + * + * Copyright (c) 2019 Robert Bosch Engineering and Business Solutions. All rights reserved. + * Copyright (c) 2020 ETAS K.K.. All rights reserved. + * Copyright (c) 2020, 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/crc16.h> +#include <asm/unaligned.h> + +#include "es58x_core.h" + +#define DRV_VERSION "1.00" +MODULE_AUTHOR("Mailhol Vincent <mailhol.vincent@wanadoo.fr>"); +MODULE_AUTHOR("Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>"); +MODULE_DESCRIPTION("Socket CAN driver for ETAS ES58X USB adapters"); +MODULE_VERSION(DRV_VERSION); +MODULE_LICENSE("GPL v2"); + +#define ES58X_MODULE_NAME "etas_es58x" +#define ES58X_VENDOR_ID 0x108C + +/* Table of devices which work with this driver. */ +static const struct usb_device_id es58x_id_table[] = { + { + /* Terminating entry */ + } +}; + +MODULE_DEVICE_TABLE(usb, es58x_id_table); + +#define es58x_print_hex_dump(buf, len) \ + print_hex_dump(KERN_DEBUG, \ + ES58X_MODULE_NAME " " __stringify(buf) ": ", \ + DUMP_PREFIX_NONE, 16, 1, buf, len, false) + +#define es58x_print_hex_dump_debug(buf, len) \ + print_hex_dump_debug(ES58X_MODULE_NAME " " __stringify(buf) ": ",\ + DUMP_PREFIX_NONE, 16, 1, buf, len, false) + +/* The last two bytes of an ES58X command is a CRC16. The first two + * bytes (the start of frame) are skipped and the CRC calculation + * starts on the third byte. + */ +#define ES58X_CRC_CALC_OFFSET 2 + +/** + * es58x_calculate_crc() - Compute the crc16 of a given URB. + * @urb_cmd: The URB command for which we want to calculate the CRC. + * @urb_len: Length of @urb_cmd. Must be at least bigger than 4 + * (ES58X_CRC_CALC_OFFSET + sizeof(crc)) + * + * Return: crc16 value. + */ +static u16 es58x_calculate_crc(const union es58x_urb_cmd *urb_cmd, u16 urb_len) +{ + u16 crc; + ssize_t len = urb_len - ES58X_CRC_CALC_OFFSET - sizeof(crc); + + crc = crc16(0, &urb_cmd->raw_cmd[ES58X_CRC_CALC_OFFSET], len); + return crc; +} + +/** + * es58x_get_crc() - Get the CRC value of a given URB. + * @urb_cmd: The URB command for which we want to get the CRC. + * @urb_len: Length of @urb_cmd. Must be at least bigger than 4 + * (ES58X_CRC_CALC_OFFSET + sizeof(crc)) + * + * Return: crc16 value. + */ +static u16 es58x_get_crc(const union es58x_urb_cmd *urb_cmd, u16 urb_len) +{ + u16 crc; + const __le16 *crc_addr; + + crc_addr = (__le16 *)&urb_cmd->raw_cmd[urb_len - sizeof(crc)]; + crc = get_unaligned_le16(crc_addr); + return crc; +} + +/** + * es58x_set_crc() - Set the CRC value of a given URB. + * @urb_cmd: The URB command for which we want to get the CRC. + * @urb_len: Length of @urb_cmd. Must be at least bigger than 4 + * (ES58X_CRC_CALC_OFFSET + sizeof(crc)) + */ +static void es58x_set_crc(union es58x_urb_cmd *urb_cmd, u16 urb_len) +{ + u16 crc; + __le16 *crc_addr; + + crc = es58x_calculate_crc(urb_cmd, urb_len); + crc_addr = (__le16 *)&urb_cmd->raw_cmd[urb_len - sizeof(crc)]; + put_unaligned_le16(crc, crc_addr); +} + +/** + * es58x_check_crc() - Validate the CRC value of a given URB. + * @es58x_dev: ES58X device. + * @urb_cmd: The URB command for which we want to check the CRC. + * @urb_len: Length of @urb_cmd. Must be at least bigger than 4 + * (ES58X_CRC_CALC_OFFSET + sizeof(crc)) + * + * Return: zero on success, -EBADMSG if the CRC check fails. + */ +static int es58x_check_crc(struct es58x_device *es58x_dev, + const union es58x_urb_cmd *urb_cmd, u16 urb_len) +{ + u16 calculated_crc = es58x_calculate_crc(urb_cmd, urb_len); + u16 expected_crc = es58x_get_crc(urb_cmd, urb_len); + + if (expected_crc != calculated_crc) { + dev_err_ratelimited(es58x_dev->dev, + "%s: Bad CRC, urb_len: %d\n", + __func__, urb_len); + return -EBADMSG; + } + + return 0; +} + +/** + * es58x_timestamp_to_ns() - Convert a timestamp value received from a + * ES58X device to nanoseconds. + * @timestamp: Timestamp received from a ES58X device. + * + * The timestamp received from ES58X is expressed in multiples of 0.5 + * micro seconds. This function converts it in to nanoseconds. + * + * Return: Timestamp value in nanoseconds. + */ +static u64 es58x_timestamp_to_ns(u64 timestamp) +{ + const u64 es58x_timestamp_ns_mult_coef = 500ULL; + + return es58x_timestamp_ns_mult_coef * timestamp; +} + +/** + * es58x_set_skb_timestamp() - Set the hardware timestamp of an skb. + * @netdev: CAN network device. + * @skb: socket buffer of a CAN message. + * @timestamp: Timestamp received from an ES58X device. + * + * Used for both received and echo messages. + */ +static void es58x_set_skb_timestamp(struct net_device *netdev, + struct sk_buff *skb, u64 timestamp) +{ + struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev; + struct skb_shared_hwtstamps *hwts; + + hwts = skb_hwtstamps(skb); + /* Ignoring overflow (overflow on 64 bits timestamp with nano + * second precision would occur after more than 500 years). + */ + hwts->hwtstamp = ns_to_ktime(es58x_timestamp_to_ns(timestamp) + + es58x_dev->realtime_diff_ns); +} + +/** + * es58x_rx_timestamp() - Handle a received timestamp. + * @es58x_dev: ES58X device. + * @timestamp: Timestamp received from a ES58X device. + * + * Calculate the difference between the ES58X device and the kernel + * internal clocks. This difference will be later used as an offset to + * convert the timestamps of RX and echo messages to match the kernel + * system time (e.g. convert to UNIX time). + */ +void es58x_rx_timestamp(struct es58x_device *es58x_dev, u64 timestamp) +{ + u64 ktime_real_ns = ktime_get_real_ns(); + u64 device_timestamp = es58x_timestamp_to_ns(timestamp); + + dev_dbg(es58x_dev->dev, "%s: request round-trip time: %llu ns\n", + __func__, ktime_real_ns - es58x_dev->ktime_req_ns); + + es58x_dev->realtime_diff_ns = + (es58x_dev->ktime_req_ns + ktime_real_ns) / 2 - device_timestamp; + es58x_dev->ktime_req_ns = 0; + + dev_dbg(es58x_dev->dev, + "%s: Device timestamp: %llu, diff with kernel: %llu\n", + __func__, device_timestamp, es58x_dev->realtime_diff_ns); +} + +/** + * es58x_set_realtime_diff_ns() - Calculate difference between the + * clocks of the ES58X device and the kernel + * @es58x_dev: ES58X device. + * + * Request a timestamp from the ES58X device. Once the answer is + * received, the timestamp difference will be set by the callback + * function es58x_rx_timestamp(). + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_set_realtime_diff_ns(struct es58x_device *es58x_dev) +{ + if (es58x_dev->ktime_req_ns) { + dev_warn(es58x_dev->dev, + "%s: Previous request to set timestamp has not completed yet\n", + __func__); + return -EBUSY; + } + + es58x_dev->ktime_req_ns = ktime_get_real_ns(); + return es58x_dev->ops->get_timestamp(es58x_dev); +} + +/** + * es58x_is_can_state_active() - Is the network device in an active + * CAN state? + * @netdev: CAN network device. + * + * The device is considered active if it is able to send or receive + * CAN frames, that is to say if it is in any of + * CAN_STATE_ERROR_ACTIVE, CAN_STATE_ERROR_WARNING or + * CAN_STATE_ERROR_PASSIVE states. + * + * Caution: when recovering from a bus-off, + * net/core/dev.c#can_restart() will call + * net/core/dev.c#can_flush_echo_skb() without using any kind of + * locks. For this reason, it is critical to guarantee that no TX or + * echo operations (i.e. any access to priv->echo_skb[]) can be done + * while this function is returning false. + * + * Return: true if the device is active, else returns false. + */ +static bool es58x_is_can_state_active(struct net_device *netdev) +{ + return es58x_priv(netdev)->can.state < CAN_STATE_BUS_OFF; +} + +/** + * es58x_is_echo_skb_threshold_reached() - Determine the limit of how + * many skb slots can be taken before we should stop the network + * queue. + * @priv: ES58X private parameters related to the network device. + * + * We need to save enough free skb slots in order to be able to do + * bulk send. This function can be used to determine when to wake or + * stop the network queue in regard to the number of skb slots already + * taken if the echo FIFO. + * + * Return: boolean. + */ +static bool es58x_is_echo_skb_threshold_reached(struct es58x_priv *priv) +{ + u32 num_echo_skb = priv->tx_head - priv->tx_tail; + u32 threshold = priv->can.echo_skb_max - + priv->es58x_dev->param->tx_bulk_max + 1; + + return num_echo_skb >= threshold; +} + +/** + * es58x_can_free_echo_skb_tail() - Remove the oldest echo skb of the + * echo FIFO. + * @netdev: CAN network device. + * + * Naming convention: the tail is the beginning of the FIFO, i.e. the + * first skb to have entered the FIFO. + */ +static void es58x_can_free_echo_skb_tail(struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + u16 fifo_mask = priv->es58x_dev->param->fifo_mask; + unsigned int frame_len = 0; + + can_free_echo_skb(netdev, priv->tx_tail & fifo_mask, &frame_len); + netdev_completed_queue(netdev, 1, frame_len); + + priv->tx_tail++; + + netdev->stats.tx_dropped++; +} + +/** + * es58x_can_get_echo_skb_recovery() - Try to re-sync the echo FIFO. + * @netdev: CAN network device. + * @rcv_packet_idx: Index + * + * This function should not be called under normal circumstances. In + * the unlikely case that one or several URB packages get dropped by + * the device, the index will get out of sync. Try to recover by + * dropping the echo skb packets with older indexes. + * + * Return: zero if recovery was successful, -EINVAL otherwise. + */ +static int es58x_can_get_echo_skb_recovery(struct net_device *netdev, + u32 rcv_packet_idx) +{ + struct es58x_priv *priv = es58x_priv(netdev); + int ret = 0; + + netdev->stats.tx_errors++; + + if (net_ratelimit()) + netdev_warn(netdev, + "Bad echo packet index: %u. First index: %u, end index %u, num_echo_skb: %02u/%02u\n", + rcv_packet_idx, priv->tx_tail, priv->tx_head, + priv->tx_head - priv->tx_tail, + priv->can.echo_skb_max); + + if ((s32)(rcv_packet_idx - priv->tx_tail) < 0) { + if (net_ratelimit()) + netdev_warn(netdev, + "Received echo index is from the past. Ignoring it\n"); + ret = -EINVAL; + } else if ((s32)(rcv_packet_idx - priv->tx_head) >= 0) { + if (net_ratelimit()) + netdev_err(netdev, + "Received echo index is from the future. Ignoring it\n"); + ret = -EINVAL; + } else { + if (net_ratelimit()) + netdev_warn(netdev, + "Recovery: dropping %u echo skb from index %u to %u\n", + rcv_packet_idx - priv->tx_tail, + priv->tx_tail, rcv_packet_idx - 1); + while (priv->tx_tail != rcv_packet_idx) { + if (priv->tx_tail == priv->tx_head) + return -EINVAL; + es58x_can_free_echo_skb_tail(netdev); + } + } + return ret; +} + +/** + * es58x_can_get_echo_skb() - Get the skb from the echo FIFO and loop + * it back locally. + * @netdev: CAN network device. + * @rcv_packet_idx: Index of the first packet received from the device. + * @tstamps: Array of hardware timestamps received from a ES58X device. + * @pkts: Number of packets (and so, length of @tstamps). + * + * Callback function for when we receive a self reception + * acknowledgment. Retrieves the skb from the echo FIFO, sets its + * hardware timestamp (the actual time it was sent) and loops it back + * locally. + * + * The device has to be active (i.e. network interface UP and not in + * bus off state or restarting). + * + * Packet indexes must be consecutive (i.e. index of first packet is + * @rcv_packet_idx, index of second packet is @rcv_packet_idx + 1 and + * index of last packet is @rcv_packet_idx + @pkts - 1). + * + * Return: zero on success. + */ +int es58x_can_get_echo_skb(struct net_device *netdev, u32 rcv_packet_idx, + u64 *tstamps, unsigned int pkts) +{ + struct es58x_priv *priv = es58x_priv(netdev); + unsigned int rx_total_frame_len = 0; + unsigned int num_echo_skb = priv->tx_head - priv->tx_tail; + int i; + u16 fifo_mask = priv->es58x_dev->param->fifo_mask; + + if (!netif_running(netdev)) { + if (net_ratelimit()) + netdev_info(netdev, + "%s: %s is down, dropping %d echo packets\n", + __func__, netdev->name, pkts); + netdev->stats.tx_dropped += pkts; + return 0; + } else if (!es58x_is_can_state_active(netdev)) { + if (net_ratelimit()) + netdev_dbg(netdev, + "Bus is off or device is restarting. Ignoring %u echo packets from index %u\n", + pkts, rcv_packet_idx); + /* stats.tx_dropped will be (or was already) + * incremented by + * drivers/net/can/net/dev.c:can_flush_echo_skb(). + */ + return 0; + } else if (num_echo_skb == 0) { + if (net_ratelimit()) + netdev_warn(netdev, + "Received %u echo packets from index: %u but echo skb queue is empty.\n", + pkts, rcv_packet_idx); + netdev->stats.tx_dropped += pkts; + return 0; + } + + if (priv->tx_tail != rcv_packet_idx) { + if (es58x_can_get_echo_skb_recovery(netdev, rcv_packet_idx) < 0) { + if (net_ratelimit()) + netdev_warn(netdev, + "Could not find echo skb for echo packet index: %u\n", + rcv_packet_idx); + return 0; + } + } + if (num_echo_skb < pkts) { + int pkts_drop = pkts - num_echo_skb; + + if (net_ratelimit()) + netdev_err(netdev, + "Received %u echo packets but have only %d echo skb. Dropping %d echo skb\n", + pkts, num_echo_skb, pkts_drop); + netdev->stats.tx_dropped += pkts_drop; + pkts -= pkts_drop; + } + + for (i = 0; i < pkts; i++) { + unsigned int skb_idx = priv->tx_tail & fifo_mask; + struct sk_buff *skb = priv->can.echo_skb[skb_idx]; + unsigned int frame_len = 0; + + if (skb) + es58x_set_skb_timestamp(netdev, skb, tstamps[i]); + + netdev->stats.tx_bytes += can_get_echo_skb(netdev, skb_idx, + &frame_len); + rx_total_frame_len += frame_len; + + priv->tx_tail++; + } + + netdev_completed_queue(netdev, pkts, rx_total_frame_len); + netdev->stats.tx_packets += pkts; + + priv->err_passive_before_rtx_success = 0; + if (!es58x_is_echo_skb_threshold_reached(priv)) + netif_wake_queue(netdev); + + return 0; +} + +/** + * es58x_can_reset_echo_fifo() - Reset the echo FIFO. + * @netdev: CAN network device. + * + * The echo_skb array of struct can_priv will be flushed by + * drivers/net/can/dev.c:can_flush_echo_skb(). This function resets + * the parameters of the struct es58x_priv of our device and reset the + * queue (c.f. BQL). + */ +static void es58x_can_reset_echo_fifo(struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + + priv->tx_tail = 0; + priv->tx_head = 0; + priv->tx_urb = NULL; + priv->err_passive_before_rtx_success = 0; + netdev_reset_queue(netdev); +} + +/** + * es58x_flush_pending_tx_msg() - Reset the buffer for transmission messages. + * @netdev: CAN network device. + * + * es58x_start_xmit() will queue up to tx_bulk_max messages in + * &tx_urb buffer and do a bulk send of all messages in one single URB + * (c.f. xmit_more flag). When the device recovers from a bus off + * state or when the device stops, the tx_urb buffer might still have + * pending messages in it and thus need to be flushed. + */ +static void es58x_flush_pending_tx_msg(struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + struct es58x_device *es58x_dev = priv->es58x_dev; + + if (priv->tx_urb) { + netdev_warn(netdev, "%s: dropping %d TX messages\n", + __func__, priv->tx_can_msg_cnt); + netdev->stats.tx_dropped += priv->tx_can_msg_cnt; + while (priv->tx_can_msg_cnt > 0) { + unsigned int frame_len = 0; + u16 fifo_mask = priv->es58x_dev->param->fifo_mask; + + priv->tx_head--; + priv->tx_can_msg_cnt--; + can_free_echo_skb(netdev, priv->tx_head & fifo_mask, + &frame_len); + netdev_completed_queue(netdev, 1, frame_len); + } + usb_anchor_urb(priv->tx_urb, &priv->es58x_dev->tx_urbs_idle); + atomic_inc(&es58x_dev->tx_urbs_idle_cnt); + usb_free_urb(priv->tx_urb); + } + priv->tx_urb = NULL; +} + +/** + * es58x_tx_ack_msg() - Handle acknowledgment messages. + * @netdev: CAN network device. + * @tx_free_entries: Number of free entries in the device transmit FIFO. + * @rx_cmd_ret_u32: error code as returned by the ES58X device. + * + * ES58X sends an acknowledgment message after a transmission request + * is done. This is mandatory for the ES581.4 but is optional (and + * deactivated in this driver) for the ES58X_FD family. + * + * Under normal circumstances, this function should never throw an + * error message. + * + * Return: zero on success, errno when any error occurs. + */ +int es58x_tx_ack_msg(struct net_device *netdev, u16 tx_free_entries, + enum es58x_ret_u32 rx_cmd_ret_u32) +{ + struct es58x_priv *priv = es58x_priv(netdev); + + if (tx_free_entries <= priv->es58x_dev->param->tx_bulk_max) { + if (net_ratelimit()) + netdev_err(netdev, + "Only %d entries left in device queue, num_echo_skb: %d/%d\n", + tx_free_entries, + priv->tx_head - priv->tx_tail, + priv->can.echo_skb_max); + netif_stop_queue(netdev); + } + + return es58x_rx_cmd_ret_u32(netdev, ES58X_RET_TYPE_TX_MSG, + rx_cmd_ret_u32); +} + +/** + * es58x_rx_can_msg() - Handle a received a CAN message. + * @netdev: CAN network device. + * @timestamp: Hardware time stamp (only relevant in rx branches). + * @data: CAN payload. + * @can_id: CAN ID. + * @es58x_flags: Please refer to enum es58x_flag. + * @dlc: Data Length Code (raw value). + * + * Fill up a CAN skb and post it. + * + * This function handles the case where the DLC of a classical CAN + * frame is greater than CAN_MAX_DLEN (c.f. the len8_dlc field of + * struct can_frame). + * + * Return: zero on success. + */ +int es58x_rx_can_msg(struct net_device *netdev, u64 timestamp, const u8 *data, + canid_t can_id, enum es58x_flag es58x_flags, u8 dlc) +{ + struct canfd_frame *cfd; + struct can_frame *ccf; + struct sk_buff *skb; + u8 len; + bool is_can_fd = !!(es58x_flags & ES58X_FLAG_FD_DATA); + + if (dlc > CAN_MAX_RAW_DLC) { + netdev_err(netdev, + "%s: DLC is %d but maximum should be %d\n", + __func__, dlc, CAN_MAX_RAW_DLC); + return -EMSGSIZE; + } + + if (is_can_fd) { + len = can_fd_dlc2len(dlc); + skb = alloc_canfd_skb(netdev, &cfd); + } else { + len = can_cc_dlc2len(dlc); + skb = alloc_can_skb(netdev, &ccf); + cfd = (struct canfd_frame *)ccf; + } + if (!skb) { + netdev->stats.rx_dropped++; + return 0; + } + + cfd->can_id = can_id; + if (es58x_flags & ES58X_FLAG_EFF) + cfd->can_id |= CAN_EFF_FLAG; + if (is_can_fd) { + cfd->len = len; + if (es58x_flags & ES58X_FLAG_FD_BRS) + cfd->flags |= CANFD_BRS; + if (es58x_flags & ES58X_FLAG_FD_ESI) + cfd->flags |= CANFD_ESI; + } else { + can_frame_set_cc_len(ccf, dlc, es58x_priv(netdev)->can.ctrlmode); + if (es58x_flags & ES58X_FLAG_RTR) { + ccf->can_id |= CAN_RTR_FLAG; + len = 0; + } + } + memcpy(cfd->data, data, len); + netdev->stats.rx_packets++; + netdev->stats.rx_bytes += len; + + es58x_set_skb_timestamp(netdev, skb, timestamp); + netif_rx(skb); + + es58x_priv(netdev)->err_passive_before_rtx_success = 0; + + return 0; +} + +/** + * es58x_rx_err_msg() - Handle a received CAN event or error message. + * @netdev: CAN network device. + * @error: Error code. + * @event: Event code. + * @timestamp: Timestamp received from a ES58X device. + * + * Handle the errors and events received by the ES58X device, create + * a CAN error skb and post it. + * + * In some rare cases the devices might get stuck alternating between + * CAN_STATE_ERROR_PASSIVE and CAN_STATE_ERROR_WARNING. To prevent + * this behavior, we force a bus off state if the device goes in + * CAN_STATE_ERROR_WARNING for ES58X_MAX_CONSECUTIVE_WARN consecutive + * times with no successful transmission or reception in between. + * + * Once the device is in bus off state, the only way to restart it is + * through the drivers/net/can/dev.c:can_restart() function. The + * device is technically capable to recover by itself under certain + * circumstances, however, allowing self recovery would create + * complex race conditions with drivers/net/can/dev.c:can_restart() + * and thus was not implemented. To activate automatic restart, please + * set the restart-ms parameter (e.g. ip link set can0 type can + * restart-ms 100). + * + * If the bus is really instable, this function would try to send a + * lot of log messages. Those are rate limited (i.e. you will see + * messages such as "net_ratelimit: XXX callbacks suppressed" in + * dmesg). + * + * Return: zero on success, errno when any error occurs. + */ +int es58x_rx_err_msg(struct net_device *netdev, enum es58x_err error, + enum es58x_event event, u64 timestamp) +{ + struct es58x_priv *priv = es58x_priv(netdev); + struct can_priv *can = netdev_priv(netdev); + struct can_device_stats *can_stats = &can->can_stats; + struct can_frame *cf = NULL; + struct sk_buff *skb; + int ret; + + if (!netif_running(netdev)) { + if (net_ratelimit()) + netdev_info(netdev, "%s: %s is down, dropping packet\n", + __func__, netdev->name); + netdev->stats.rx_dropped++; + return 0; + } + + if (error == ES58X_ERR_OK && event == ES58X_EVENT_OK) { + netdev_err(netdev, "%s: Both error and event are zero\n", + __func__); + return -EINVAL; + } + + skb = alloc_can_err_skb(netdev, &cf); + + switch (error) { + case ES58X_ERR_OK: /* 0: No error */ + break; + + case ES58X_ERR_PROT_STUFF: + if (net_ratelimit()) + netdev_dbg(netdev, "Error BITSUFF\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_STUFF; + break; + + case ES58X_ERR_PROT_FORM: + if (net_ratelimit()) + netdev_dbg(netdev, "Error FORMAT\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_FORM; + break; + + case ES58X_ERR_ACK: + if (net_ratelimit()) + netdev_dbg(netdev, "Error ACK\n"); + if (cf) + cf->can_id |= CAN_ERR_ACK; + break; + + case ES58X_ERR_PROT_BIT: + if (net_ratelimit()) + netdev_dbg(netdev, "Error BIT\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_BIT; + break; + + case ES58X_ERR_PROT_CRC: + if (net_ratelimit()) + netdev_dbg(netdev, "Error CRC\n"); + if (cf) + cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ; + break; + + case ES58X_ERR_PROT_BIT1: + if (net_ratelimit()) + netdev_dbg(netdev, + "Error: expected a recessive bit but monitored a dominant one\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_BIT1; + break; + + case ES58X_ERR_PROT_BIT0: + if (net_ratelimit()) + netdev_dbg(netdev, + "Error expected a dominant bit but monitored a recessive one\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_BIT0; + break; + + case ES58X_ERR_PROT_OVERLOAD: + if (net_ratelimit()) + netdev_dbg(netdev, "Error OVERLOAD\n"); + if (cf) + cf->data[2] |= CAN_ERR_PROT_OVERLOAD; + break; + + case ES58X_ERR_PROT_UNSPEC: + if (net_ratelimit()) + netdev_dbg(netdev, "Unspecified error\n"); + if (cf) + cf->can_id |= CAN_ERR_PROT; + break; + + default: + if (net_ratelimit()) + netdev_err(netdev, + "%s: Unspecified error code 0x%04X\n", + __func__, (int)error); + if (cf) + cf->can_id |= CAN_ERR_PROT; + break; + } + + switch (event) { + case ES58X_EVENT_OK: /* 0: No event */ + break; + + case ES58X_EVENT_CRTL_ACTIVE: + if (can->state == CAN_STATE_BUS_OFF) { + netdev_err(netdev, + "%s: state transition: BUS OFF -> ACTIVE\n", + __func__); + } + if (net_ratelimit()) + netdev_dbg(netdev, "Event CAN BUS ACTIVE\n"); + if (cf) + cf->data[1] |= CAN_ERR_CRTL_ACTIVE; + can->state = CAN_STATE_ERROR_ACTIVE; + break; + + case ES58X_EVENT_CRTL_PASSIVE: + if (net_ratelimit()) + netdev_dbg(netdev, "Event CAN BUS PASSIVE\n"); + /* Either TX or RX error count reached passive state + * but we do not know which. Setting both flags by + * default. + */ + if (cf) { + cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; + cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE; + } + if (can->state < CAN_STATE_BUS_OFF) + can->state = CAN_STATE_ERROR_PASSIVE; + can_stats->error_passive++; + if (priv->err_passive_before_rtx_success < U8_MAX) + priv->err_passive_before_rtx_success++; + break; + + case ES58X_EVENT_CRTL_WARNING: + if (net_ratelimit()) + netdev_dbg(netdev, "Event CAN BUS WARNING\n"); + /* Either TX or RX error count reached warning state + * but we do not know which. Setting both flags by + * default. + */ + if (cf) { + cf->data[1] |= CAN_ERR_CRTL_RX_WARNING; + cf->data[1] |= CAN_ERR_CRTL_TX_WARNING; + } + if (can->state < CAN_STATE_BUS_OFF) + can->state = CAN_STATE_ERROR_WARNING; + can_stats->error_warning++; + break; + + case ES58X_EVENT_BUSOFF: + if (net_ratelimit()) + netdev_dbg(netdev, "Event CAN BUS OFF\n"); + if (cf) + cf->can_id |= CAN_ERR_BUSOFF; + can_stats->bus_off++; + netif_stop_queue(netdev); + if (can->state != CAN_STATE_BUS_OFF) { + can->state = CAN_STATE_BUS_OFF; + can_bus_off(netdev); + ret = can->do_set_mode(netdev, CAN_MODE_STOP); + if (ret) + return ret; + } + break; + + case ES58X_EVENT_SINGLE_WIRE: + if (net_ratelimit()) + netdev_warn(netdev, + "Lost connection on either CAN high or CAN low\n"); + /* Lost connection on either CAN high or CAN + * low. Setting both flags by default. + */ + if (cf) { + cf->data[4] |= CAN_ERR_TRX_CANH_NO_WIRE; + cf->data[4] |= CAN_ERR_TRX_CANL_NO_WIRE; + } + break; + + default: + if (net_ratelimit()) + netdev_err(netdev, + "%s: Unspecified event code 0x%04X\n", + __func__, (int)event); + if (cf) + cf->can_id |= CAN_ERR_CRTL; + break; + } + + /* driver/net/can/dev.c:can_restart() takes in account error + * messages in the RX stats. Doing the same here for + * consistency. + */ + netdev->stats.rx_packets++; + netdev->stats.rx_bytes += cf->can_dlc; + + if (cf) { + if (cf->data[1]) + cf->can_id |= CAN_ERR_CRTL; + if (cf->data[2] || cf->data[3]) { + cf->can_id |= CAN_ERR_PROT; + can_stats->bus_error++; + } + if (cf->data[4]) + cf->can_id |= CAN_ERR_TRX; + + es58x_set_skb_timestamp(netdev, skb, timestamp); + netif_rx(skb); + } + + if ((event & ES58X_EVENT_CRTL_PASSIVE) && + priv->err_passive_before_rtx_success == ES58X_CONSECUTIVE_ERR_PASSIVE_MAX) { + netdev_info(netdev, + "Got %d consecutive warning events with no successful RX or TX. Forcing bus-off\n", + priv->err_passive_before_rtx_success); + return es58x_rx_err_msg(netdev, ES58X_ERR_OK, + ES58X_EVENT_BUSOFF, timestamp); + } + + return 0; +} + +/** + * es58x_cmd_ret_desc() - Convert a command type to a string. + * @cmd_ret_type: Type of the command which triggered the return code. + * + * The final line (return "<unknown>") should not be reached. If this + * is the case, there is an implementation bug. + * + * Return: a readable description of the @cmd_ret_type. + */ +static const char *es58x_cmd_ret_desc(enum es58x_ret_type cmd_ret_type) +{ + switch (cmd_ret_type) { + case ES58X_RET_TYPE_SET_BITTIMING: + return "Set bittiming"; + case ES58X_RET_TYPE_ENABLE_CHANNEL: + return "Enable channel"; + case ES58X_RET_TYPE_DISABLE_CHANNEL: + return "Disable channel"; + case ES58X_RET_TYPE_TX_MSG: + return "Transmit message"; + case ES58X_RET_TYPE_RESET_RX: + return "Reset RX"; + case ES58X_RET_TYPE_RESET_TX: + return "Reset TX"; + case ES58X_RET_TYPE_DEVICE_ERR: + return "Device error"; + } + + return "<unknown>"; +}; + +/** + * es58x_rx_cmd_ret_u8() - Handle the command's return code received + * from the ES58X device. + * @dev: Device, only used for the dev_XXX() print functions. + * @cmd_ret_type: Type of the command which triggered the return code. + * @rx_cmd_ret_u8: Command error code as returned by the ES58X device. + * + * Handles the 8 bits command return code. Those are specific to the + * ES581.4 device. The return value will eventually be used by + * es58x_handle_urb_cmd() function which will take proper actions in + * case of critical issues such and memory errors or bad CRC values. + * + * In contrast with es58x_rx_cmd_ret_u32(), the network device is + * unknown. + * + * Return: zero on success, return errno when any error occurs. + */ +int es58x_rx_cmd_ret_u8(struct device *dev, + enum es58x_ret_type cmd_ret_type, + enum es58x_ret_u8 rx_cmd_ret_u8) +{ + const char *ret_desc = es58x_cmd_ret_desc(cmd_ret_type); + + switch (rx_cmd_ret_u8) { + case ES58X_RET_U8_OK: + dev_dbg_ratelimited(dev, "%s: OK\n", ret_desc); + return 0; + + case ES58X_RET_U8_ERR_UNSPECIFIED_FAILURE: + dev_err(dev, "%s: unspecified failure\n", ret_desc); + return -EBADMSG; + + case ES58X_RET_U8_ERR_NO_MEM: + dev_err(dev, "%s: device ran out of memory\n", ret_desc); + return -ENOMEM; + + case ES58X_RET_U8_ERR_BAD_CRC: + dev_err(dev, "%s: CRC of previous command is incorrect\n", + ret_desc); + return -EIO; + + default: + dev_err(dev, "%s: returned unknown value: 0x%02X\n", + ret_desc, rx_cmd_ret_u8); + return -EBADMSG; + } +} + +/** + * es58x_rx_cmd_ret_u32() - Handle the command return code received + * from the ES58X device. + * @netdev: CAN network device. + * @cmd_ret_type: Type of the command which triggered the return code. + * @rx_cmd_ret_u32: error code as returned by the ES58X device. + * + * Handles the 32 bits command return code. The return value will + * eventually be used by es58x_handle_urb_cmd() function which will + * take proper actions in case of critical issues such and memory + * errors or bad CRC values. + * + * Return: zero on success, errno when any error occurs. + */ +int es58x_rx_cmd_ret_u32(struct net_device *netdev, + enum es58x_ret_type cmd_ret_type, + enum es58x_ret_u32 rx_cmd_ret_u32) +{ + struct es58x_priv *priv = es58x_priv(netdev); + const struct es58x_operators *ops = priv->es58x_dev->ops; + const char *ret_desc = es58x_cmd_ret_desc(cmd_ret_type); + + switch (rx_cmd_ret_u32) { + case ES58X_RET_U32_OK: + switch (cmd_ret_type) { + case ES58X_RET_TYPE_ENABLE_CHANNEL: + es58x_can_reset_echo_fifo(netdev); + priv->can.state = CAN_STATE_ERROR_ACTIVE; + netif_wake_queue(netdev); + netdev_info(netdev, + "%s: %s (Serial Number %s): CAN%d channel becomes ready\n", + ret_desc, priv->es58x_dev->udev->product, + priv->es58x_dev->udev->serial, + priv->channel_idx + 1); + break; + + case ES58X_RET_TYPE_TX_MSG: + if (IS_ENABLED(CONFIG_VERBOSE_DEBUG) && net_ratelimit()) + netdev_vdbg(netdev, "%s: OK\n", ret_desc); + break; + + default: + netdev_dbg(netdev, "%s: OK\n", ret_desc); + break; + } + return 0; + + case ES58X_RET_U32_ERR_UNSPECIFIED_FAILURE: + if (cmd_ret_type == ES58X_RET_TYPE_ENABLE_CHANNEL) { + int ret; + + netdev_warn(netdev, + "%s: channel is already opened, closing and re-openning it to reflect new configuration\n", + ret_desc); + ret = ops->disable_channel(es58x_priv(netdev)); + if (ret) + return ret; + return ops->enable_channel(es58x_priv(netdev)); + } + if (cmd_ret_type == ES58X_RET_TYPE_DISABLE_CHANNEL) { + netdev_info(netdev, + "%s: channel is already closed\n", ret_desc); + return 0; + } + netdev_err(netdev, + "%s: unspecified failure\n", ret_desc); + return -EBADMSG; + + case ES58X_RET_U32_ERR_NO_MEM: + netdev_err(netdev, "%s: device ran out of memory\n", ret_desc); + return -ENOMEM; + + case ES58X_RET_U32_WARN_PARAM_ADJUSTED: + netdev_warn(netdev, + "%s: some incompatible parameters have been adjusted\n", + ret_desc); + return 0; + + case ES58X_RET_U32_WARN_TX_MAYBE_REORDER: + netdev_warn(netdev, + "%s: TX messages might have been reordered\n", + ret_desc); + return 0; + + case ES58X_RET_U32_ERR_TIMEDOUT: + netdev_err(netdev, "%s: command timed out\n", ret_desc); + return -ETIMEDOUT; + + case ES58X_RET_U32_ERR_FIFO_FULL: + netdev_warn(netdev, "%s: fifo is full\n", ret_desc); + return 0; + + case ES58X_RET_U32_ERR_BAD_CONFIG: + netdev_err(netdev, "%s: bad configuration\n", ret_desc); + return -EINVAL; + + case ES58X_RET_U32_ERR_NO_RESOURCE: + netdev_err(netdev, "%s: no resource available\n", ret_desc); + return -EBUSY; + + default: + netdev_err(netdev, "%s returned unknown value: 0x%08X\n", + ret_desc, rx_cmd_ret_u32); + return -EBADMSG; + } +} + +/** + * es58x_increment_rx_errors() - Increment the network devices' error + * count. + * @es58x_dev: ES58X device. + * + * If an error occurs on the early stages on receiving an URB command, + * we might not be able to figure out on which network device the + * error occurred. In such case, we arbitrarily increment the error + * count of all the network devices attached to our ES58X device. + */ +static void es58x_increment_rx_errors(struct es58x_device *es58x_dev) +{ + int i; + + for (i = 0; i < es58x_dev->num_can_ch; i++) + if (es58x_dev->netdev[i]) + es58x_dev->netdev[i]->stats.rx_errors++; +} + +/** + * es58x_handle_urb_cmd() - Handle the URB command + * @es58x_dev: ES58X device. + * @urb_cmd: The URB command received from the ES58X device, might not + * be aligned. + * + * Sends the URB command to the device specific function. Manages the + * errors thrown back by those functions. + */ +static void es58x_handle_urb_cmd(struct es58x_device *es58x_dev, + const union es58x_urb_cmd *urb_cmd) +{ + const struct es58x_operators *ops = es58x_dev->ops; + size_t cmd_len; + int i, ret; + + ret = ops->handle_urb_cmd(es58x_dev, urb_cmd); + switch (ret) { + case 0: /* OK */ + return; + + case -ENODEV: + dev_err_ratelimited(es58x_dev->dev, "Device is not ready\n"); + break; + + case -EINVAL: + case -EMSGSIZE: + case -EBADRQC: + case -EBADMSG: + case -ECHRNG: + case -ETIMEDOUT: + cmd_len = es58x_get_urb_cmd_len(es58x_dev, + ops->get_msg_len(urb_cmd)); + dev_err(es58x_dev->dev, + "ops->handle_urb_cmd() returned error %pe", + ERR_PTR(ret)); + es58x_print_hex_dump(urb_cmd, cmd_len); + break; + + case -EFAULT: + case -ENOMEM: + case -EIO: + default: + dev_crit(es58x_dev->dev, + "ops->handle_urb_cmd() returned error %pe, detaching all network devices\n", + ERR_PTR(ret)); + for (i = 0; i < es58x_dev->num_can_ch; i++) + if (es58x_dev->netdev[i]) + netif_device_detach(es58x_dev->netdev[i]); + if (es58x_dev->ops->reset_device) + es58x_dev->ops->reset_device(es58x_dev); + break; + } + + /* Because the urb command could not fully be parsed, + * channel_id is not confirmed. Incrementing rx_errors count + * of all channels. + */ + es58x_increment_rx_errors(es58x_dev); +} + +/** + * es58x_check_rx_urb() - Check the length and format of the URB command. + * @es58x_dev: ES58X device. + * @urb_cmd: The URB command received from the ES58X device, might not + * be aligned. + * @urb_actual_len: The actual length of the URB command. + * + * Check if the first message of the received urb is valid, that is to + * say that both the header and the length are coherent. + * + * Return: + * the length of the first message of the URB on success. + * + * -ENODATA if the URB command is incomplete (in which case, the URB + * command should be buffered and combined with the next URB to try to + * reconstitute the URB command). + * + * -EOVERFLOW if the length is bigger than the maximum expected one. + * + * -EBADRQC if the start of frame does not match the expected value. + */ +static signed int es58x_check_rx_urb(struct es58x_device *es58x_dev, + const union es58x_urb_cmd *urb_cmd, + u32 urb_actual_len) +{ + const struct device *dev = es58x_dev->dev; + const struct es58x_parameters *param = es58x_dev->param; + u16 sof, msg_len; + signed int urb_cmd_len, ret; + + if (urb_actual_len < param->urb_cmd_header_len) { + dev_vdbg(dev, + "%s: Received %d bytes [%*ph]: header incomplete\n", + __func__, urb_actual_len, urb_actual_len, + urb_cmd->raw_cmd); + return -ENODATA; + } + + sof = get_unaligned_le16(&urb_cmd->sof); + if (sof != param->rx_start_of_frame) { + dev_err_ratelimited(es58x_dev->dev, + "%s: Expected sequence 0x%04X for start of frame but got 0x%04X.\n", + __func__, param->rx_start_of_frame, sof); + return -EBADRQC; + } + + msg_len = es58x_dev->ops->get_msg_len(urb_cmd); + urb_cmd_len = es58x_get_urb_cmd_len(es58x_dev, msg_len); + if (urb_cmd_len > param->rx_urb_cmd_max_len) { + dev_err_ratelimited(es58x_dev->dev, + "%s: Biggest expected size for rx urb_cmd is %u but receive a command of size %d\n", + __func__, + param->rx_urb_cmd_max_len, urb_cmd_len); + return -EOVERFLOW; + } else if (urb_actual_len < urb_cmd_len) { + dev_vdbg(dev, "%s: Received %02d/%02d bytes\n", + __func__, urb_actual_len, urb_cmd_len); + return -ENODATA; + } + + ret = es58x_check_crc(es58x_dev, urb_cmd, urb_cmd_len); + if (ret) + return ret; + + return urb_cmd_len; +} + +/** + * es58x_copy_to_cmd_buf() - Copy an array to the URB command buffer. + * @es58x_dev: ES58X device. + * @raw_cmd: the buffer we want to copy. + * @raw_cmd_len: length of @raw_cmd. + * + * Concatenates @raw_cmd_len bytes of @raw_cmd to the end of the URB + * command buffer. + * + * Return: zero on success, -EMSGSIZE if not enough space is available + * to do the copy. + */ +static int es58x_copy_to_cmd_buf(struct es58x_device *es58x_dev, + u8 *raw_cmd, int raw_cmd_len) +{ + if (es58x_dev->rx_cmd_buf_len + raw_cmd_len > + es58x_dev->param->rx_urb_cmd_max_len) + return -EMSGSIZE; + + memcpy(&es58x_dev->rx_cmd_buf.raw_cmd[es58x_dev->rx_cmd_buf_len], + raw_cmd, raw_cmd_len); + es58x_dev->rx_cmd_buf_len += raw_cmd_len; + + return 0; +} + +/** + * es58x_split_urb_try_recovery() - Try to recover bad URB sequences. + * @es58x_dev: ES58X device. + * @raw_cmd: pointer to the buffer we want to copy. + * @raw_cmd_len: length of @raw_cmd. + * + * Under some rare conditions, we might get incorrect URBs from the + * device. From our observations, one of the valid URB gets replaced + * by one from the past. The full root cause is not identified. + * + * This function looks for the next start of frame in the urb buffer + * in order to try to recover. + * + * Such behavior was not observed on the devices of the ES58X FD + * family and only seems to impact the ES581.4. + * + * Return: the number of bytes dropped on success, -EBADMSG if recovery failed. + */ +static int es58x_split_urb_try_recovery(struct es58x_device *es58x_dev, + u8 *raw_cmd, size_t raw_cmd_len) +{ + union es58x_urb_cmd *urb_cmd; + signed int urb_cmd_len; + u16 sof; + int dropped_bytes = 0; + + es58x_increment_rx_errors(es58x_dev); + + while (raw_cmd_len > sizeof(sof)) { + urb_cmd = (union es58x_urb_cmd *)raw_cmd; + sof = get_unaligned_le16(&urb_cmd->sof); + + if (sof == es58x_dev->param->rx_start_of_frame) { + urb_cmd_len = es58x_check_rx_urb(es58x_dev, + urb_cmd, raw_cmd_len); + if ((urb_cmd_len == -ENODATA) || urb_cmd_len > 0) { + dev_info_ratelimited(es58x_dev->dev, + "Recovery successful! Dropped %d bytes (urb_cmd_len: %d)\n", + dropped_bytes, + urb_cmd_len); + return dropped_bytes; + } + } + raw_cmd++; + raw_cmd_len--; + dropped_bytes++; + } + + dev_warn_ratelimited(es58x_dev->dev, "%s: Recovery failed\n", __func__); + return -EBADMSG; +} + +/** + * es58x_handle_incomplete_cmd() - Reconstitute an URB command from + * different URB pieces. + * @es58x_dev: ES58X device. + * @urb: last urb buffer received. + * + * The device might split the URB commands in an arbitrary amount of + * pieces. This function concatenates those in an URB buffer until a + * full URB command is reconstituted and consume it. + * + * Return: + * number of bytes consumed from @urb if successful. + * + * -ENODATA if the URB command is still incomplete. + * + * -EBADMSG if the URB command is incorrect. + */ +static signed int es58x_handle_incomplete_cmd(struct es58x_device *es58x_dev, + struct urb *urb) +{ + size_t cpy_len; + signed int urb_cmd_len, tmp_cmd_buf_len, ret; + + tmp_cmd_buf_len = es58x_dev->rx_cmd_buf_len; + cpy_len = min_t(int, es58x_dev->param->rx_urb_cmd_max_len - + es58x_dev->rx_cmd_buf_len, urb->actual_length); + ret = es58x_copy_to_cmd_buf(es58x_dev, urb->transfer_buffer, cpy_len); + if (ret < 0) + return ret; + + urb_cmd_len = es58x_check_rx_urb(es58x_dev, &es58x_dev->rx_cmd_buf, + es58x_dev->rx_cmd_buf_len); + if (urb_cmd_len == -ENODATA) { + return -ENODATA; + } else if (urb_cmd_len < 0) { + dev_err_ratelimited(es58x_dev->dev, + "Could not reconstitute incomplete command from previous URB, dropping %d bytes\n", + tmp_cmd_buf_len + urb->actual_length); + dev_err_ratelimited(es58x_dev->dev, + "Error code: %pe, es58x_dev->rx_cmd_buf_len: %d, urb->actual_length: %u\n", + ERR_PTR(urb_cmd_len), + tmp_cmd_buf_len, urb->actual_length); + es58x_print_hex_dump(&es58x_dev->rx_cmd_buf, tmp_cmd_buf_len); + es58x_print_hex_dump(urb->transfer_buffer, urb->actual_length); + return urb->actual_length; + } + + es58x_handle_urb_cmd(es58x_dev, &es58x_dev->rx_cmd_buf); + return urb_cmd_len - tmp_cmd_buf_len; /* consumed length */ +} + +/** + * es58x_split_urb() - Cut the received URB in individual URB commands. + * @es58x_dev: ES58X device. + * @urb: last urb buffer received. + * + * The device might send urb in bulk format (i.e. several URB commands + * concatenated together). This function will split all the commands + * contained in the urb. + * + * Return: + * number of bytes consumed from @urb if successful. + * + * -ENODATA if the URB command is incomplete. + * + * -EBADMSG if the URB command is incorrect. + */ +static signed int es58x_split_urb(struct es58x_device *es58x_dev, + struct urb *urb) +{ + union es58x_urb_cmd *urb_cmd; + u8 *raw_cmd = urb->transfer_buffer; + s32 raw_cmd_len = urb->actual_length; + int ret; + + if (es58x_dev->rx_cmd_buf_len != 0) { + ret = es58x_handle_incomplete_cmd(es58x_dev, urb); + if (ret != -ENODATA) + es58x_dev->rx_cmd_buf_len = 0; + if (ret < 0) + return ret; + + raw_cmd += ret; + raw_cmd_len -= ret; + } + + while (raw_cmd_len > 0) { + if (raw_cmd[0] == ES58X_HEARTBEAT) { + raw_cmd++; + raw_cmd_len--; + continue; + } + urb_cmd = (union es58x_urb_cmd *)raw_cmd; + ret = es58x_check_rx_urb(es58x_dev, urb_cmd, raw_cmd_len); + if (ret > 0) { + es58x_handle_urb_cmd(es58x_dev, urb_cmd); + } else if (ret == -ENODATA) { + es58x_copy_to_cmd_buf(es58x_dev, raw_cmd, raw_cmd_len); + return -ENODATA; + } else if (ret < 0) { + ret = es58x_split_urb_try_recovery(es58x_dev, raw_cmd, + raw_cmd_len); + if (ret < 0) + return ret; + } + raw_cmd += ret; + raw_cmd_len -= ret; + } + + return 0; +} + +/** + * es58x_read_bulk_callback() - Callback for reading data from device. + * @urb: last urb buffer received. + * + * This function gets eventually called each time an URB is received + * from the ES58X device. + * + * Checks urb status, calls read function and resubmits urb read + * operation. + */ +static void es58x_read_bulk_callback(struct urb *urb) +{ + struct es58x_device *es58x_dev = urb->context; + const struct device *dev = es58x_dev->dev; + int i, ret; + + switch (urb->status) { + case 0: /* success */ + break; + + case -EOVERFLOW: + dev_err_ratelimited(dev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + es58x_print_hex_dump_debug(urb->transfer_buffer, + urb->transfer_buffer_length); + goto resubmit_urb; + + case -EPROTO: + dev_warn_ratelimited(dev, "%s: error %pe. Device unplugged?\n", + __func__, ERR_PTR(urb->status)); + goto free_urb; + + case -ENOENT: + case -EPIPE: + dev_err_ratelimited(dev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + goto free_urb; + + case -ESHUTDOWN: + dev_dbg_ratelimited(dev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + goto free_urb; + + default: + dev_err_ratelimited(dev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + goto resubmit_urb; + } + + ret = es58x_split_urb(es58x_dev, urb); + if ((ret != -ENODATA) && ret < 0) { + dev_err(es58x_dev->dev, "es58x_split_urb() returned error %pe", + ERR_PTR(ret)); + es58x_print_hex_dump_debug(urb->transfer_buffer, + urb->actual_length); + + /* Because the urb command could not be parsed, + * channel_id is not confirmed. Incrementing rx_errors + * count of all channels. + */ + es58x_increment_rx_errors(es58x_dev); + } + + resubmit_urb: + usb_fill_bulk_urb(urb, es58x_dev->udev, es58x_dev->rx_pipe, + urb->transfer_buffer, urb->transfer_buffer_length, + es58x_read_bulk_callback, es58x_dev); + + ret = usb_submit_urb(urb, GFP_ATOMIC); + if (ret == -ENODEV) { + for (i = 0; i < es58x_dev->num_can_ch; i++) + if (es58x_dev->netdev[i]) + netif_device_detach(es58x_dev->netdev[i]); + } else if (ret) + dev_err_ratelimited(dev, + "Failed resubmitting read bulk urb: %pe\n", + ERR_PTR(ret)); + return; + + free_urb: + usb_free_coherent(urb->dev, urb->transfer_buffer_length, + urb->transfer_buffer, urb->transfer_dma); +} + +/** + * es58x_write_bulk_callback() - Callback after writing data to the device. + * @urb: urb buffer which was previously submitted. + * + * This function gets eventually called each time an URB was sent to + * the ES58X device. + * + * Puts the @urb back to the urbs idle anchor and tries to restart the + * network queue. + */ +static void es58x_write_bulk_callback(struct urb *urb) +{ + struct net_device *netdev = urb->context; + struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev; + + switch (urb->status) { + case 0: /* success */ + break; + + case -EOVERFLOW: + if (net_ratelimit()) + netdev_err(netdev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + es58x_print_hex_dump(urb->transfer_buffer, + urb->transfer_buffer_length); + break; + + case -ENOENT: + if (net_ratelimit()) + netdev_dbg(netdev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + usb_free_coherent(urb->dev, + es58x_dev->param->tx_urb_cmd_max_len, + urb->transfer_buffer, urb->transfer_dma); + return; + + default: + if (net_ratelimit()) + netdev_info(netdev, "%s: error %pe\n", + __func__, ERR_PTR(urb->status)); + break; + } + + usb_anchor_urb(urb, &es58x_dev->tx_urbs_idle); + atomic_inc(&es58x_dev->tx_urbs_idle_cnt); +} + +/** + * es58x_alloc_urb() - Allocate memory for an URB and its transfer + * buffer. + * @es58x_dev: ES58X device. + * @urb: URB to be allocated. + * @buf: used to return DMA address of buffer. + * @buf_len: requested buffer size. + * @mem_flags: affect whether allocation may block. + * + * Allocates an URB and its @transfer_buffer and set its @transfer_dma + * address. + * + * This function is used at start-up to allocate all RX URBs at once + * and during run time for TX URBs. + * + * Return: zero on success, -ENOMEM if no memory is available. + */ +static int es58x_alloc_urb(struct es58x_device *es58x_dev, struct urb **urb, + u8 **buf, size_t buf_len, gfp_t mem_flags) +{ + *urb = usb_alloc_urb(0, mem_flags); + if (!*urb) { + dev_err(es58x_dev->dev, "No memory left for URBs\n"); + return -ENOMEM; + } + + *buf = usb_alloc_coherent(es58x_dev->udev, buf_len, + mem_flags, &(*urb)->transfer_dma); + if (!*buf) { + dev_err(es58x_dev->dev, "No memory left for USB buffer\n"); + usb_free_urb(*urb); + return -ENOMEM; + } + + (*urb)->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + + return 0; +} + +/** + * es58x_get_tx_urb() - Get an URB for transmission. + * @es58x_dev: ES58X device. + * + * Gets an URB from the idle urbs anchor or allocate a new one if the + * anchor is empty. + * + * If there are more than ES58X_TX_URBS_MAX in the idle anchor, do + * some garbage collection. The garbage collection is done here + * instead of within es58x_write_bulk_callback() because + * usb_free_coherent() should not be used in IRQ context: + * c.f. WARN_ON(irqs_disabled()) in dma_free_attrs(). + * + * Return: a pointer to an URB on success, NULL if no memory is + * available. + */ +static struct urb *es58x_get_tx_urb(struct es58x_device *es58x_dev) +{ + atomic_t *idle_cnt = &es58x_dev->tx_urbs_idle_cnt; + struct urb *urb = usb_get_from_anchor(&es58x_dev->tx_urbs_idle); + + if (!urb) { + size_t tx_buf_len; + u8 *buf; + + tx_buf_len = es58x_dev->param->tx_urb_cmd_max_len; + if (es58x_alloc_urb(es58x_dev, &urb, &buf, tx_buf_len, + GFP_ATOMIC)) + return NULL; + + usb_fill_bulk_urb(urb, es58x_dev->udev, es58x_dev->tx_pipe, + buf, tx_buf_len, NULL, NULL); + return urb; + } + + while (atomic_dec_return(idle_cnt) > ES58X_TX_URBS_MAX) { + /* Garbage collector */ + struct urb *tmp = usb_get_from_anchor(&es58x_dev->tx_urbs_idle); + + if (!tmp) + break; + usb_free_coherent(tmp->dev, + es58x_dev->param->tx_urb_cmd_max_len, + tmp->transfer_buffer, tmp->transfer_dma); + usb_free_urb(tmp); + } + + return urb; +} + +/** + * es58x_submit_urb() - Send data to the device. + * @es58x_dev: ES58X device. + * @urb: URB to be sent. + * @netdev: CAN network device. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_submit_urb(struct es58x_device *es58x_dev, struct urb *urb, + struct net_device *netdev) +{ + int ret; + + es58x_set_crc(urb->transfer_buffer, urb->transfer_buffer_length); + usb_fill_bulk_urb(urb, es58x_dev->udev, es58x_dev->tx_pipe, + urb->transfer_buffer, urb->transfer_buffer_length, + es58x_write_bulk_callback, netdev); + usb_anchor_urb(urb, &es58x_dev->tx_urbs_busy); + ret = usb_submit_urb(urb, GFP_ATOMIC); + if (ret) { + netdev_err(netdev, "%s: USB send urb failure: %pe\n", + __func__, ERR_PTR(ret)); + usb_unanchor_urb(urb); + usb_free_coherent(urb->dev, + es58x_dev->param->tx_urb_cmd_max_len, + urb->transfer_buffer, urb->transfer_dma); + } + usb_free_urb(urb); + + return ret; +} + +/** + * es58x_send_msg() - Prepare an URB and submit it. + * @es58x_dev: ES58X device. + * @cmd_type: Command type. + * @cmd_id: Command ID. + * @msg: ES58X message to be sent. + * @msg_len: Length of @msg. + * @channel_idx: Index of the network device. + * + * Creates an URB command from a given message, sets the header and the + * CRC and then submits it. + * + * Return: zero on success, errno when any error occurs. + */ +int es58x_send_msg(struct es58x_device *es58x_dev, u8 cmd_type, u8 cmd_id, + const void *msg, u16 msg_len, int channel_idx) +{ + struct net_device *netdev; + union es58x_urb_cmd *urb_cmd; + struct urb *urb; + int urb_cmd_len; + + if (channel_idx == ES58X_CHANNEL_IDX_NA) + netdev = es58x_dev->netdev[0]; /* Default to first channel */ + else + netdev = es58x_dev->netdev[channel_idx]; + + urb_cmd_len = es58x_get_urb_cmd_len(es58x_dev, msg_len); + if (urb_cmd_len > es58x_dev->param->tx_urb_cmd_max_len) + return -EOVERFLOW; + + urb = es58x_get_tx_urb(es58x_dev); + if (!urb) + return -ENOMEM; + + urb_cmd = urb->transfer_buffer; + es58x_dev->ops->fill_urb_header(urb_cmd, cmd_type, cmd_id, + channel_idx, msg_len); + memcpy(&urb_cmd->raw_cmd[es58x_dev->param->urb_cmd_header_len], + msg, msg_len); + urb->transfer_buffer_length = urb_cmd_len; + + return es58x_submit_urb(es58x_dev, urb, netdev); +} + +/** + * es58x_alloc_rx_urbs() - Allocate RX URBs. + * @es58x_dev: ES58X device. + * + * Allocate URBs for reception and anchor them. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_alloc_rx_urbs(struct es58x_device *es58x_dev) +{ + const struct device *dev = es58x_dev->dev; + const struct es58x_parameters *param = es58x_dev->param; + size_t rx_buf_len = es58x_dev->rx_max_packet_size; + struct urb *urb; + u8 *buf; + int i; + int ret = -EINVAL; + + for (i = 0; i < param->rx_urb_max; i++) { + ret = es58x_alloc_urb(es58x_dev, &urb, &buf, rx_buf_len, + GFP_KERNEL); + if (ret) + break; + + usb_fill_bulk_urb(urb, es58x_dev->udev, es58x_dev->rx_pipe, + buf, rx_buf_len, es58x_read_bulk_callback, + es58x_dev); + usb_anchor_urb(urb, &es58x_dev->rx_urbs); + + ret = usb_submit_urb(urb, GFP_KERNEL); + if (ret) { + usb_unanchor_urb(urb); + usb_free_coherent(es58x_dev->udev, rx_buf_len, + buf, urb->transfer_dma); + usb_free_urb(urb); + break; + } + usb_free_urb(urb); + } + + if (i == 0) { + dev_err(dev, "%s: Could not setup any rx URBs\n", __func__); + return ret; + } + dev_dbg(dev, "%s: Allocated %d rx URBs each of size %zu\n", + __func__, i, rx_buf_len); + + return ret; +} + +/** + * es58x_free_urbs() - Free all the TX and RX URBs. + * @es58x_dev: ES58X device. + */ +static void es58x_free_urbs(struct es58x_device *es58x_dev) +{ + struct urb *urb; + + if (!usb_wait_anchor_empty_timeout(&es58x_dev->tx_urbs_busy, 1000)) { + dev_err(es58x_dev->dev, "%s: Timeout, some TX urbs still remain\n", + __func__); + usb_kill_anchored_urbs(&es58x_dev->tx_urbs_busy); + } + + while ((urb = usb_get_from_anchor(&es58x_dev->tx_urbs_idle)) != NULL) { + usb_free_coherent(urb->dev, es58x_dev->param->tx_urb_cmd_max_len, + urb->transfer_buffer, urb->transfer_dma); + usb_free_urb(urb); + atomic_dec(&es58x_dev->tx_urbs_idle_cnt); + } + if (atomic_read(&es58x_dev->tx_urbs_idle_cnt)) + dev_err(es58x_dev->dev, + "All idle urbs were freed but tx_urb_idle_cnt is %d\n", + atomic_read(&es58x_dev->tx_urbs_idle_cnt)); + + usb_kill_anchored_urbs(&es58x_dev->rx_urbs); +} + +/** + * es58x_open() - Enable the network device. + * @netdev: CAN network device. + * + * Called when the network transitions to the up state. Allocate the + * URB resources if needed and open the channel. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_open(struct net_device *netdev) +{ + struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev; + int ret; + + if (atomic_inc_return(&es58x_dev->opened_channel_cnt) == 1) { + ret = es58x_alloc_rx_urbs(es58x_dev); + if (ret) + return ret; + + ret = es58x_set_realtime_diff_ns(es58x_dev); + if (ret) + goto free_urbs; + } + + ret = open_candev(netdev); + if (ret) + goto free_urbs; + + ret = es58x_dev->ops->enable_channel(es58x_priv(netdev)); + if (ret) + goto free_urbs; + + netif_start_queue(netdev); + + return ret; + + free_urbs: + if (atomic_dec_and_test(&es58x_dev->opened_channel_cnt)) + es58x_free_urbs(es58x_dev); + netdev_err(netdev, "%s: Could not open the network device: %pe\n", + __func__, ERR_PTR(ret)); + + return ret; +} + +/** + * es58x_stop() - Disable the network device. + * @netdev: CAN network device. + * + * Called when the network transitions to the down state. If all the + * channels of the device are closed, free the URB resources which are + * not needed anymore. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_stop(struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + struct es58x_device *es58x_dev = priv->es58x_dev; + int ret; + + netif_stop_queue(netdev); + ret = es58x_dev->ops->disable_channel(priv); + if (ret) + return ret; + + priv->can.state = CAN_STATE_STOPPED; + es58x_can_reset_echo_fifo(netdev); + close_candev(netdev); + + es58x_flush_pending_tx_msg(netdev); + + if (atomic_dec_and_test(&es58x_dev->opened_channel_cnt)) + es58x_free_urbs(es58x_dev); + + return 0; +} + +/** + * es58x_xmit_commit() - Send the bulk urb. + * @netdev: CAN network device. + * + * Do the bulk send. This function should be called only once by bulk + * transmission. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_xmit_commit(struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + int ret; + + if (!es58x_is_can_state_active(netdev)) + return -ENETDOWN; + + if (es58x_is_echo_skb_threshold_reached(priv)) + netif_stop_queue(netdev); + + ret = es58x_submit_urb(priv->es58x_dev, priv->tx_urb, netdev); + if (ret == 0) + priv->tx_urb = NULL; + + return ret; +} + +/** + * es58x_xmit_more() - Can we put more packets? + * @priv: ES58X private parameters related to the network device. + * + * Return: true if we can put more, false if it is time to send. + */ +static bool es58x_xmit_more(struct es58x_priv *priv) +{ + unsigned int free_slots = + priv->can.echo_skb_max - (priv->tx_head - priv->tx_tail); + + return netdev_xmit_more() && free_slots > 0 && + priv->tx_can_msg_cnt < priv->es58x_dev->param->tx_bulk_max; +} + +/** + * es58x_start_xmit() - Transmit an skb. + * @skb: socket buffer of a CAN message. + * @netdev: CAN network device. + * + * Called when a packet needs to be transmitted. + * + * This function relies on Byte Queue Limits (BQL). The main benefit + * is to increase the throughput by allowing bulk transfers + * (c.f. xmit_more flag). + * + * Queues up to tx_bulk_max messages in &tx_urb buffer and does + * a bulk send of all messages in one single URB. + * + * Return: NETDEV_TX_OK regardless of if we could transmit the @skb or + * had to drop it. + */ +static netdev_tx_t es58x_start_xmit(struct sk_buff *skb, + struct net_device *netdev) +{ + struct es58x_priv *priv = es58x_priv(netdev); + struct es58x_device *es58x_dev = priv->es58x_dev; + unsigned int frame_len; + int ret; + + if (can_dropped_invalid_skb(netdev, skb)) { + if (priv->tx_urb) + goto xmit_commit; + return NETDEV_TX_OK; + } + + if (priv->tx_urb && priv->tx_can_msg_is_fd != can_is_canfd_skb(skb)) { + /* Can not do bulk send with mixed CAN and CAN FD frames. */ + ret = es58x_xmit_commit(netdev); + if (ret) + goto drop_skb; + } + + if (!priv->tx_urb) { + priv->tx_urb = es58x_get_tx_urb(es58x_dev); + if (!priv->tx_urb) { + ret = -ENOMEM; + goto drop_skb; + } + priv->tx_can_msg_cnt = 0; + priv->tx_can_msg_is_fd = can_is_canfd_skb(skb); + } + + ret = es58x_dev->ops->tx_can_msg(priv, skb); + if (ret) + goto drop_skb; + + frame_len = can_skb_get_frame_len(skb); + ret = can_put_echo_skb(skb, netdev, + priv->tx_head & es58x_dev->param->fifo_mask, + frame_len); + if (ret) + goto xmit_failure; + netdev_sent_queue(netdev, frame_len); + + priv->tx_head++; + priv->tx_can_msg_cnt++; + + xmit_commit: + if (!es58x_xmit_more(priv)) { + ret = es58x_xmit_commit(netdev); + if (ret) + goto xmit_failure; + } + + return NETDEV_TX_OK; + + drop_skb: + dev_kfree_skb(skb); + netdev->stats.tx_dropped++; + xmit_failure: + netdev_warn(netdev, "%s: send message failure: %pe\n", + __func__, ERR_PTR(ret)); + netdev->stats.tx_errors++; + es58x_flush_pending_tx_msg(netdev); + return NETDEV_TX_OK; +} + +static const struct net_device_ops es58x_netdev_ops = { + .ndo_open = es58x_open, + .ndo_stop = es58x_stop, + .ndo_start_xmit = es58x_start_xmit +}; + +/** + * es58x_set_mode() - Change network device mode. + * @netdev: CAN network device. + * @mode: either %CAN_MODE_START, %CAN_MODE_STOP or %CAN_MODE_SLEEP + * + * Currently, this function is only used to stop and restart the + * channel during a bus off event (c.f. es58x_rx_err_msg() and + * drivers/net/can/dev.c:can_restart() which are the two only + * callers). + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_set_mode(struct net_device *netdev, enum can_mode mode) +{ + struct es58x_priv *priv = es58x_priv(netdev); + + switch (mode) { + case CAN_MODE_START: + switch (priv->can.state) { + case CAN_STATE_BUS_OFF: + return priv->es58x_dev->ops->enable_channel(priv); + + case CAN_STATE_STOPPED: + return es58x_open(netdev); + + case CAN_STATE_ERROR_ACTIVE: + case CAN_STATE_ERROR_WARNING: + case CAN_STATE_ERROR_PASSIVE: + default: + return 0; + } + + case CAN_MODE_STOP: + switch (priv->can.state) { + case CAN_STATE_STOPPED: + return 0; + + case CAN_STATE_ERROR_ACTIVE: + case CAN_STATE_ERROR_WARNING: + case CAN_STATE_ERROR_PASSIVE: + case CAN_STATE_BUS_OFF: + default: + return priv->es58x_dev->ops->disable_channel(priv); + } + + case CAN_MODE_SLEEP: + default: + return -EOPNOTSUPP; + } +} + +/** + * es58x_init_priv() - Initialize private parameters. + * @es58x_dev: ES58X device. + * @priv: ES58X private parameters related to the network device. + * @channel_idx: Index of the network device. + */ +static void es58x_init_priv(struct es58x_device *es58x_dev, + struct es58x_priv *priv, int channel_idx) +{ + const struct es58x_parameters *param = es58x_dev->param; + struct can_priv *can = &priv->can; + + priv->es58x_dev = es58x_dev; + priv->channel_idx = channel_idx; + priv->tx_urb = NULL; + priv->tx_can_msg_cnt = 0; + + can->bittiming_const = param->bittiming_const; + if (param->ctrlmode_supported & CAN_CTRLMODE_FD) { + can->data_bittiming_const = param->data_bittiming_const; + can->tdc_const = param->tdc_const; + } + can->bitrate_max = param->bitrate_max; + can->clock = param->clock; + can->state = CAN_STATE_STOPPED; + can->ctrlmode_supported = param->ctrlmode_supported; + can->do_set_mode = es58x_set_mode; +} + +/** + * es58x_init_netdev() - Initialize the network device. + * @es58x_dev: ES58X device. + * @channel_idx: Index of the network device. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_init_netdev(struct es58x_device *es58x_dev, int channel_idx) +{ + struct net_device *netdev; + struct device *dev = es58x_dev->dev; + int ret; + + netdev = alloc_candev(sizeof(struct es58x_priv), + es58x_dev->param->fifo_mask + 1); + if (!netdev) { + dev_err(dev, "Could not allocate candev\n"); + return -ENOMEM; + } + SET_NETDEV_DEV(netdev, dev); + es58x_dev->netdev[channel_idx] = netdev; + es58x_init_priv(es58x_dev, es58x_priv(netdev), channel_idx); + + netdev->netdev_ops = &es58x_netdev_ops; + netdev->flags |= IFF_ECHO; /* We support local echo */ + + ret = register_candev(netdev); + if (ret) + return ret; + + netdev_queue_set_dql_min_limit(netdev_get_tx_queue(netdev, 0), + es58x_dev->param->dql_min_limit); + + return ret; +} + +/** + * es58x_get_product_info() - Get the product information and print them. + * @es58x_dev: ES58X device. + * + * Do a synchronous call to get the product information. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_get_product_info(struct es58x_device *es58x_dev) +{ + struct usb_device *udev = es58x_dev->udev; + const int es58x_prod_info_idx = 6; + /* Empirical tests show a prod_info length of maximum 83, + * below should be more than enough. + */ + const size_t prod_info_len = 127; + char *prod_info; + int ret; + + prod_info = kmalloc(prod_info_len, GFP_KERNEL); + if (!prod_info) + return -ENOMEM; + + ret = usb_string(udev, es58x_prod_info_idx, prod_info, prod_info_len); + if (ret < 0) { + dev_err(es58x_dev->dev, + "%s: Could not read the product info: %pe\n", + __func__, ERR_PTR(ret)); + goto out_free; + } + if (ret >= prod_info_len - 1) { + dev_warn(es58x_dev->dev, + "%s: Buffer is too small, result might be truncated\n", + __func__); + } + dev_info(es58x_dev->dev, "Product info: %s\n", prod_info); + + out_free: + kfree(prod_info); + return ret < 0 ? ret : 0; +} + +/** + * es58x_init_es58x_dev() - Initialize the ES58X device. + * @intf: USB interface. + * @p_es58x_dev: pointer to the address of the ES58X device. + * @driver_info: Quirks of the device. + * + * Return: zero on success, errno when any error occurs. + */ +static int es58x_init_es58x_dev(struct usb_interface *intf, + struct es58x_device **p_es58x_dev, + kernel_ulong_t driver_info) +{ + struct device *dev = &intf->dev; + struct es58x_device *es58x_dev; + const struct es58x_parameters *param; + const struct es58x_operators *ops; + struct usb_device *udev = interface_to_usbdev(intf); + struct usb_endpoint_descriptor *ep_in, *ep_out; + int ret; + + dev_info(dev, + "Starting %s %s (Serial Number %s) driver version %s\n", + udev->manufacturer, udev->product, udev->serial, DRV_VERSION); + + ret = usb_find_common_endpoints(intf->cur_altsetting, &ep_in, &ep_out, + NULL, NULL); + if (ret) + return ret; + + if (driver_info & ES58X_FD_FAMILY) { + return -ENODEV; + /* Place holder for es58x_fd glue code. */ + } else { + return -ENODEV; + /* Place holder for es581_4 glue code. */ + } + + es58x_dev = kzalloc(es58x_sizeof_es58x_device(param), GFP_KERNEL); + if (!es58x_dev) + return -ENOMEM; + + es58x_dev->param = param; + es58x_dev->ops = ops; + es58x_dev->dev = dev; + es58x_dev->udev = udev; + + if (driver_info & ES58X_DUAL_CHANNEL) + es58x_dev->num_can_ch = 2; + else + es58x_dev->num_can_ch = 1; + + init_usb_anchor(&es58x_dev->rx_urbs); + init_usb_anchor(&es58x_dev->tx_urbs_idle); + init_usb_anchor(&es58x_dev->tx_urbs_busy); + atomic_set(&es58x_dev->tx_urbs_idle_cnt, 0); + atomic_set(&es58x_dev->opened_channel_cnt, 0); + usb_set_intfdata(intf, es58x_dev); + + es58x_dev->rx_pipe = usb_rcvbulkpipe(es58x_dev->udev, + ep_in->bEndpointAddress); + es58x_dev->tx_pipe = usb_sndbulkpipe(es58x_dev->udev, + ep_out->bEndpointAddress); + es58x_dev->rx_max_packet_size = le16_to_cpu(ep_in->wMaxPacketSize); + + *p_es58x_dev = es58x_dev; + + return 0; +} + +/** + * es58x_probe() - Initialize the USB device. + * @intf: USB interface. + * @id: USB device ID. + * + * Return: zero on success, -ENODEV if the interface is not supported + * or errno when any other error occurs. + */ +static int es58x_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct es58x_device *es58x_dev; + int ch_idx, ret; + + ret = es58x_init_es58x_dev(intf, &es58x_dev, id->driver_info); + if (ret) + return ret; + + ret = es58x_get_product_info(es58x_dev); + if (ret) + goto cleanup_es58x_dev; + + for (ch_idx = 0; ch_idx < es58x_dev->num_can_ch; ch_idx++) { + ret = es58x_init_netdev(es58x_dev, ch_idx); + if (ret) + goto cleanup_candev; + } + + return ret; + + cleanup_candev: + for (ch_idx = 0; ch_idx < es58x_dev->num_can_ch; ch_idx++) + if (es58x_dev->netdev[ch_idx]) { + unregister_candev(es58x_dev->netdev[ch_idx]); + free_candev(es58x_dev->netdev[ch_idx]); + } + cleanup_es58x_dev: + kfree(es58x_dev); + + return ret; +} + +/** + * es58x_disconnect() - Disconnect the USB device. + * @intf: USB interface + * + * Called by the usb core when driver is unloaded or device is + * removed. + */ +static void es58x_disconnect(struct usb_interface *intf) +{ + struct es58x_device *es58x_dev = usb_get_intfdata(intf); + struct net_device *netdev; + int i; + + dev_info(&intf->dev, "Disconnecting %s %s\n", + es58x_dev->udev->manufacturer, es58x_dev->udev->product); + + for (i = 0; i < es58x_dev->num_can_ch; i++) { + netdev = es58x_dev->netdev[i]; + if (!netdev) + continue; + unregister_candev(netdev); + es58x_dev->netdev[i] = NULL; + free_candev(netdev); + } + + es58x_free_urbs(es58x_dev); + + kfree(es58x_dev); + usb_set_intfdata(intf, NULL); +} + +static struct usb_driver es58x_driver = { + .name = ES58X_MODULE_NAME, + .probe = es58x_probe, + .disconnect = es58x_disconnect, + .id_table = es58x_id_table +}; + +module_usb_driver(es58x_driver); diff --git a/drivers/net/can/usb/etas_es58x/es58x_core.h b/drivers/net/can/usb/etas_es58x/es58x_core.h new file mode 100644 index 000000000000..ccced39d5d81 --- /dev/null +++ b/drivers/net/can/usb/etas_es58x/es58x_core.h @@ -0,0 +1,693 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces. + * + * File es58x_core.h: All common definitions and declarations. + * + * Copyright (c) 2019 Robert Bosch Engineering and Business Solutions. All rights reserved. + * Copyright (c) 2020 ETAS K.K.. All rights reserved. + * Copyright (c) 2020, 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr> + */ + +#ifndef __ES58X_COMMON_H__ +#define __ES58X_COMMON_H__ + +#include <linux/types.h> +#include <linux/usb.h> +#include <linux/netdevice.h> +#include <linux/can.h> +#include <linux/can/dev.h> + +/* Driver constants */ +#define ES58X_RX_URBS_MAX 5 /* Empirical value */ +#define ES58X_TX_URBS_MAX 6 /* Empirical value */ + +#define ES58X_MAX(param) 0 +#define ES58X_TX_BULK_MAX ES58X_MAX(TX_BULK_MAX) +#define ES58X_RX_BULK_MAX ES58X_MAX(RX_BULK_MAX) +#define ES58X_ECHO_BULK_MAX ES58X_MAX(ECHO_BULK_MAX) +#define ES58X_NUM_CAN_CH_MAX ES58X_MAX(NUM_CAN_CH) + +/* Use this when channel index is irrelevant (e.g. device + * timestamp). + */ +#define ES58X_CHANNEL_IDX_NA 0xFF +#define ES58X_EMPTY_MSG NULL + +/* Threshold on consecutive CAN_STATE_ERROR_PASSIVE. If we receive + * ES58X_CONSECUTIVE_ERR_PASSIVE_MAX times the event + * ES58X_ERR_CRTL_PASSIVE in a row without any successful RX or TX, + * we force the device to switch to CAN_STATE_BUS_OFF state. + */ +#define ES58X_CONSECUTIVE_ERR_PASSIVE_MAX 254 + +/* A magic number sent by the ES581.4 to inform it is alive. */ +#define ES58X_HEARTBEAT 0x11 + +/** + * enum es58x_driver_info - Quirks of the device. + * @ES58X_DUAL_CHANNEL: Device has two CAN channels. If this flag is + * not set, it is implied that the device has only one CAN + * channel. + * @ES58X_FD_FAMILY: Device is CAN-FD capable. If this flag is not + * set, the device only supports classical CAN. + */ +enum es58x_driver_info { + ES58X_DUAL_CHANNEL = BIT(0), + ES58X_FD_FAMILY = BIT(1) +}; + +enum es58x_echo { + ES58X_ECHO_OFF = 0, + ES58X_ECHO_ON = 1 +}; + +/** + * enum es58x_physical_layer - Type of the physical layer. + * @ES58X_PHYSICAL_LAYER_HIGH_SPEED: High-speed CAN (c.f. ISO + * 11898-2). + * + * Some products of the ETAS portfolio also support low-speed CAN + * (c.f. ISO 11898-3). However, all the devices in scope of this + * driver do not support the option, thus, the enum has only one + * member. + */ +enum es58x_physical_layer { + ES58X_PHYSICAL_LAYER_HIGH_SPEED = 1 +}; + +enum es58x_samples_per_bit { + ES58X_SAMPLES_PER_BIT_ONE = 1, + ES58X_SAMPLES_PER_BIT_THREE = 2 +}; + +/** + * enum es58x_sync_edge - Synchronization method. + * @ES58X_SYNC_EDGE_SINGLE: ISO CAN specification defines the use of a + * single edge synchronization. The synchronization should be + * done on recessive to dominant level change. + * + * For information, ES582.1 and ES584.1 also support a double + * synchronization, requiring both recessive to dominant then dominant + * to recessive level change. However, this is not supported in + * SocketCAN framework, thus, the enum has only one member. + */ +enum es58x_sync_edge { + ES58X_SYNC_EDGE_SINGLE = 1 +}; + +/** + * enum es58x_flag - CAN flags for RX/TX messages. + * @ES58X_FLAG_EFF: Extended Frame Format (EFF). + * @ES58X_FLAG_RTR: Remote Transmission Request (RTR). + * @ES58X_FLAG_FD_BRS: Bit rate switch (BRS): second bitrate for + * payload data. + * @ES58X_FLAG_FD_ESI: Error State Indicator (ESI): tell if the + * transmitting node is in error passive mode. + * @ES58X_FLAG_FD_DATA: CAN FD frame. + */ +enum es58x_flag { + ES58X_FLAG_EFF = BIT(0), + ES58X_FLAG_RTR = BIT(1), + ES58X_FLAG_FD_BRS = BIT(3), + ES58X_FLAG_FD_ESI = BIT(5), + ES58X_FLAG_FD_DATA = BIT(6) +}; + +/** + * enum es58x_err - CAN error detection. + * @ES58X_ERR_OK: No errors. + * @ES58X_ERR_PROT_STUFF: Bit stuffing error: more than 5 consecutive + * equal bits. + * @ES58X_ERR_PROT_FORM: Frame format error. + * @ES58X_ERR_ACK: Received no ACK on transmission. + * @ES58X_ERR_PROT_BIT: Single bit error. + * @ES58X_ERR_PROT_CRC: Incorrect 15, 17 or 21 bits CRC. + * @ES58X_ERR_PROT_BIT1: Unable to send recessive bit: tried to send + * recessive bit 1 but monitored dominant bit 0. + * @ES58X_ERR_PROT_BIT0: Unable to send dominant bit: tried to send + * dominant bit 0 but monitored recessive bit 1. + * @ES58X_ERR_PROT_OVERLOAD: Bus overload. + * @ES58X_ERR_PROT_UNSPEC: Unspecified. + * + * Please refer to ISO 11898-1:2015, section 10.11 "Error detection" + * and section 10.13 "Overload signaling" for additional details. + */ +enum es58x_err { + ES58X_ERR_OK = 0, + ES58X_ERR_PROT_STUFF = BIT(0), + ES58X_ERR_PROT_FORM = BIT(1), + ES58X_ERR_ACK = BIT(2), + ES58X_ERR_PROT_BIT = BIT(3), + ES58X_ERR_PROT_CRC = BIT(4), + ES58X_ERR_PROT_BIT1 = BIT(5), + ES58X_ERR_PROT_BIT0 = BIT(6), + ES58X_ERR_PROT_OVERLOAD = BIT(7), + ES58X_ERR_PROT_UNSPEC = BIT(31) +}; + +/** + * enum es58x_event - CAN error codes returned by the device. + * @ES58X_EVENT_OK: No errors. + * @ES58X_EVENT_CRTL_ACTIVE: Active state: both TR and RX error count + * is less than 128. + * @ES58X_EVENT_CRTL_PASSIVE: Passive state: either TX or RX error + * count is greater than 127. + * @ES58X_EVENT_CRTL_WARNING: Warning state: either TX or RX error + * count is greater than 96. + * @ES58X_EVENT_BUSOFF: Bus off. + * @ES58X_EVENT_SINGLE_WIRE: Lost connection on either CAN high or CAN + * low. + * + * Please refer to ISO 11898-1:2015, section 12.1.4 "Rules of fault + * confinement" for additional details. + */ +enum es58x_event { + ES58X_EVENT_OK = 0, + ES58X_EVENT_CRTL_ACTIVE = BIT(0), + ES58X_EVENT_CRTL_PASSIVE = BIT(1), + ES58X_EVENT_CRTL_WARNING = BIT(2), + ES58X_EVENT_BUSOFF = BIT(3), + ES58X_EVENT_SINGLE_WIRE = BIT(4) +}; + +/* enum es58x_ret_u8 - Device return error codes, 8 bit format. + * + * Specific to ES581.4. + */ +enum es58x_ret_u8 { + ES58X_RET_U8_OK = 0x00, + ES58X_RET_U8_ERR_UNSPECIFIED_FAILURE = 0x80, + ES58X_RET_U8_ERR_NO_MEM = 0x81, + ES58X_RET_U8_ERR_BAD_CRC = 0x99 +}; + +/* enum es58x_ret_u32 - Device return error codes, 32 bit format. + */ +enum es58x_ret_u32 { + ES58X_RET_U32_OK = 0x00000000UL, + ES58X_RET_U32_ERR_UNSPECIFIED_FAILURE = 0x80000000UL, + ES58X_RET_U32_ERR_NO_MEM = 0x80004001UL, + ES58X_RET_U32_WARN_PARAM_ADJUSTED = 0x40004000UL, + ES58X_RET_U32_WARN_TX_MAYBE_REORDER = 0x40004001UL, + ES58X_RET_U32_ERR_TIMEDOUT = 0x80000008UL, + ES58X_RET_U32_ERR_FIFO_FULL = 0x80003002UL, + ES58X_RET_U32_ERR_BAD_CONFIG = 0x80004000UL, + ES58X_RET_U32_ERR_NO_RESOURCE = 0x80004002UL +}; + +/* enum es58x_ret_type - Type of the command returned by the ES58X + * device. + */ +enum es58x_ret_type { + ES58X_RET_TYPE_SET_BITTIMING, + ES58X_RET_TYPE_ENABLE_CHANNEL, + ES58X_RET_TYPE_DISABLE_CHANNEL, + ES58X_RET_TYPE_TX_MSG, + ES58X_RET_TYPE_RESET_RX, + ES58X_RET_TYPE_RESET_TX, + ES58X_RET_TYPE_DEVICE_ERR +}; + +union es58x_urb_cmd { + struct { /* Common header parts of all variants */ + __le16 sof; + u8 cmd_type; + u8 cmd_id; + } __packed; + u8 raw_cmd[0]; +}; + +/** + * struct es58x_priv - All information specific to a CAN channel. + * @can: struct can_priv must be the first member (Socket CAN relies + * on the fact that function netdev_priv() returns a pointer to + * a struct can_priv). + * @es58x_dev: pointer to the corresponding ES58X device. + * @tx_urb: Used as a buffer to concatenate the TX messages and to do + * a bulk send. Please refer to es58x_start_xmit() for more + * details. + * @tx_tail: Index of the oldest packet still pending for + * completion. @tx_tail & echo_skb_mask represents the beginning + * of the echo skb FIFO, i.e. index of the first element. + * @tx_head: Index of the next packet to be sent to the + * device. @tx_head & echo_skb_mask represents the end of the + * echo skb FIFO plus one, i.e. the first free index. + * @tx_can_msg_cnt: Number of messages in @tx_urb. + * @tx_can_msg_is_fd: false: all messages in @tx_urb are Classical + * CAN, true: all messages in @tx_urb are CAN FD. Rationale: + * ES58X FD devices do not allow to mix Classical CAN and FD CAN + * frames in one single bulk transmission. + * @err_passive_before_rtx_success: The ES58X device might enter in a + * state in which it keeps alternating between error passive + * and active states. This counter keeps track of the number of + * error passive and if it gets bigger than + * ES58X_CONSECUTIVE_ERR_PASSIVE_MAX, es58x_rx_err_msg() will + * force the status to bus-off. + * @channel_idx: Channel index, starts at zero. + */ +struct es58x_priv { + struct can_priv can; + struct es58x_device *es58x_dev; + struct urb *tx_urb; + + u32 tx_tail; + u32 tx_head; + + u8 tx_can_msg_cnt; + bool tx_can_msg_is_fd; + + u8 err_passive_before_rtx_success; + + u8 channel_idx; +}; + +/** + * struct es58x_parameters - Constant parameters of a given hardware + * variant. + * @bittiming_const: Nominal bittimming constant parameters. + * @data_bittiming_const: Data bittiming constant parameters. + * @tdc_const: Transmission Delay Compensation constant parameters. + * @bitrate_max: Maximum bitrate supported by the device. + * @clock: CAN clock parameters. + * @ctrlmode_supported: List of supported modes. Please refer to + * can/netlink.h file for additional details. + * @tx_start_of_frame: Magic number at the beginning of each TX URB + * command. + * @rx_start_of_frame: Magic number at the beginning of each RX URB + * command. + * @tx_urb_cmd_max_len: Maximum length of a TX URB command. + * @rx_urb_cmd_max_len: Maximum length of a RX URB command. + * @fifo_mask: Bit mask to quickly convert the tx_tail and tx_head + * field of the struct es58x_priv into echo_skb + * indexes. Properties: @fifo_mask = echos_skb_max - 1 where + * echo_skb_max must be a power of two. Also, echo_skb_max must + * not exceed the maximum size of the device internal TX FIFO + * length. This parameter is used to control the network queue + * wake/stop logic. + * @dql_min_limit: Dynamic Queue Limits (DQL) absolute minimum limit + * of bytes allowed to be queued on this network device transmit + * queue. Used by the Byte Queue Limits (BQL) to determine how + * frequently the xmit_more flag will be set to true in + * es58x_start_xmit(). Set this value higher to optimize for + * throughput but be aware that it might have a negative impact + * on the latency! This value can also be set dynamically. Please + * refer to Documentation/ABI/testing/sysfs-class-net-queues for + * more details. + * @tx_bulk_max: Maximum number of TX messages that can be sent in one + * single URB packet. + * @urb_cmd_header_len: Length of the URB command header. + * @rx_urb_max: Number of RX URB to be allocated during device probe. + * @tx_urb_max: Number of TX URB to be allocated during device probe. + */ +struct es58x_parameters { + const struct can_bittiming_const *bittiming_const; + const struct can_bittiming_const *data_bittiming_const; + const struct can_tdc_const *tdc_const; + u32 bitrate_max; + struct can_clock clock; + u32 ctrlmode_supported; + u16 tx_start_of_frame; + u16 rx_start_of_frame; + u16 tx_urb_cmd_max_len; + u16 rx_urb_cmd_max_len; + u16 fifo_mask; + u16 dql_min_limit; + u8 tx_bulk_max; + u8 urb_cmd_header_len; + u8 rx_urb_max; + u8 tx_urb_max; +}; + +/** + * struct es58x_operators - Function pointers used to encode/decode + * the TX/RX messages. + * @get_msg_len: Get field msg_len of the urb_cmd. The offset of + * msg_len inside urb_cmd depends of the device model. + * @handle_urb_cmd: Decode the URB command received from the device + * and dispatch it to the relevant sub function. + * @fill_urb_header: Fill the header of urb_cmd. + * @tx_can_msg: Encode a TX CAN message and add it to the bulk buffer + * cmd_buf of es58x_dev. + * @enable_channel: Start the CAN channel. + * @disable_channel: Stop the CAN channel. + * @reset_device: Full reset of the device. N.B: this feature is only + * present on the ES581.4. For ES58X FD devices, this field is + * set to NULL. + * @get_timestamp: Request a timestamp from the ES58X device. + */ +struct es58x_operators { + u16 (*get_msg_len)(const union es58x_urb_cmd *urb_cmd); + int (*handle_urb_cmd)(struct es58x_device *es58x_dev, + const union es58x_urb_cmd *urb_cmd); + void (*fill_urb_header)(union es58x_urb_cmd *urb_cmd, u8 cmd_type, + u8 cmd_id, u8 channel_idx, u16 cmd_len); + int (*tx_can_msg)(struct es58x_priv *priv, const struct sk_buff *skb); + int (*enable_channel)(struct es58x_priv *priv); + int (*disable_channel)(struct es58x_priv *priv); + int (*reset_device)(struct es58x_device *es58x_dev); + int (*get_timestamp)(struct es58x_device *es58x_dev); +}; + +/** + * struct es58x_device - All information specific to an ES58X device. + * @dev: Device information. + * @udev: USB device information. + * @netdev: Array of our CAN channels. + * @param: The constant parameters. + * @ops: Operators. + * @rx_pipe: USB reception pipe. + * @tx_pipe: USB transmission pipe. + * @rx_urbs: Anchor for received URBs. + * @tx_urbs_busy: Anchor for TX URBs which were send to the device. + * @tx_urbs_idle: Anchor for TX USB which are idle. This driver + * allocates the memory for the URBs during the probe. When a TX + * URB is needed, it can be taken from this anchor. The network + * queue wake/stop logic should prevent this URB from getting + * empty. Please refer to es58x_get_tx_urb() for more details. + * @tx_urbs_idle_cnt: number of urbs in @tx_urbs_idle. + * @opened_channel_cnt: number of channels opened (c.f. es58x_open() + * and es58x_stop()). + * @ktime_req_ns: kernel timestamp when es58x_set_realtime_diff_ns() + * was called. + * @realtime_diff_ns: difference in nanoseconds between the clocks of + * the ES58X device and the kernel. + * @timestamps: a temporary buffer to store the time stamps before + * feeding them to es58x_can_get_echo_skb(). Can only be used + * in RX branches. + * @rx_max_packet_size: Maximum length of bulk-in URB. + * @num_can_ch: Number of CAN channel (i.e. number of elements of @netdev). + * @rx_cmd_buf_len: Length of @rx_cmd_buf. + * @rx_cmd_buf: The device might split the URB commands in an + * arbitrary amount of pieces. This buffer is used to concatenate + * all those pieces. Can only be used in RX branches. This field + * has to be the last one of the structure because it is has a + * flexible size (c.f. es58x_sizeof_es58x_device() function). + */ +struct es58x_device { + struct device *dev; + struct usb_device *udev; + struct net_device *netdev[ES58X_NUM_CAN_CH_MAX]; + + const struct es58x_parameters *param; + const struct es58x_operators *ops; + + int rx_pipe; + int tx_pipe; + + struct usb_anchor rx_urbs; + struct usb_anchor tx_urbs_busy; + struct usb_anchor tx_urbs_idle; + atomic_t tx_urbs_idle_cnt; + atomic_t opened_channel_cnt; + + u64 ktime_req_ns; + s64 realtime_diff_ns; + + u64 timestamps[ES58X_ECHO_BULK_MAX]; + + u16 rx_max_packet_size; + u8 num_can_ch; + + u16 rx_cmd_buf_len; + union es58x_urb_cmd rx_cmd_buf; +}; + +/** + * es58x_sizeof_es58x_device() - Calculate the maximum length of + * struct es58x_device. + * @es58x_dev_param: The constant parameters of the device. + * + * The length of struct es58x_device depends on the length of its last + * field: rx_cmd_buf. This macro allows to optimize the memory + * allocation. + * + * Return: length of struct es58x_device. + */ +static inline size_t es58x_sizeof_es58x_device(const struct es58x_parameters + *es58x_dev_param) +{ + return offsetof(struct es58x_device, rx_cmd_buf) + + es58x_dev_param->rx_urb_cmd_max_len; +} + +static inline int __es58x_check_msg_len(const struct device *dev, + const char *stringified_msg, + size_t actual_len, size_t expected_len) +{ + if (expected_len != actual_len) { + dev_err(dev, + "Length of %s is %zu but received command is %zu.\n", + stringified_msg, expected_len, actual_len); + return -EMSGSIZE; + } + return 0; +} + +/** + * es58x_check_msg_len() - Check the size of a received message. + * @dev: Device, used to print error messages. + * @msg: Received message, must not be a pointer. + * @actual_len: Length of the message as advertised in the command header. + * + * Must be a macro in order to accept the different types of messages + * as an input. Can be use with any of the messages which have a fixed + * length. Check for an exact match of the size. + * + * Return: zero on success, -EMSGSIZE if @actual_len differs from the + * expected length. + */ +#define es58x_check_msg_len(dev, msg, actual_len) \ + __es58x_check_msg_len(dev, __stringify(msg), \ + actual_len, sizeof(msg)) + +static inline int __es58x_check_msg_max_len(const struct device *dev, + const char *stringified_msg, + size_t actual_len, + size_t expected_len) +{ + if (actual_len > expected_len) { + dev_err(dev, + "Maximum length for %s is %zu but received command is %zu.\n", + stringified_msg, expected_len, actual_len); + return -EOVERFLOW; + } + return 0; +} + +/** + * es58x_check_msg_max_len() - Check the maximum size of a received message. + * @dev: Device, used to print error messages. + * @msg: Received message, must not be a pointer. + * @actual_len: Length of the message as advertised in the command header. + * + * Must be a macro in order to accept the different types of messages + * as an input. To be used with the messages of variable sizes. Only + * check that the message is not bigger than the maximum expected + * size. + * + * Return: zero on success, -EOVERFLOW if @actual_len is greater than + * the expected length. + */ +#define es58x_check_msg_max_len(dev, msg, actual_len) \ + __es58x_check_msg_max_len(dev, __stringify(msg), \ + actual_len, sizeof(msg)) + +static inline int __es58x_msg_num_element(const struct device *dev, + const char *stringified_msg, + size_t actual_len, size_t msg_len, + size_t elem_len) +{ + size_t actual_num_elem = actual_len / elem_len; + size_t expected_num_elem = msg_len / elem_len; + + if (actual_num_elem == 0) { + dev_err(dev, + "Minimum length for %s is %zu but received command is %zu.\n", + stringified_msg, elem_len, actual_len); + return -EMSGSIZE; + } else if ((actual_len % elem_len) != 0) { + dev_err(dev, + "Received command length: %zu is not a multiple of %s[0]: %zu\n", + actual_len, stringified_msg, elem_len); + return -EMSGSIZE; + } else if (actual_num_elem > expected_num_elem) { + dev_err(dev, + "Array %s is supposed to have %zu elements each of size %zu...\n", + stringified_msg, expected_num_elem, elem_len); + dev_err(dev, + "... But received command has %zu elements (total length %zu).\n", + actual_num_elem, actual_len); + return -EOVERFLOW; + } + return actual_num_elem; +} + +/** + * es58x_msg_num_element() - Check size and give the number of + * elements in a message of array type. + * @dev: Device, used to print error messages. + * @msg: Received message, must be an array. + * @actual_len: Length of the message as advertised in the command + * header. + * + * Must be a macro in order to accept the different types of messages + * as an input. To be used on message of array type. Array's element + * has to be of fixed size (else use es58x_check_msg_max_len()). Check + * that the total length is an exact multiple of the length of a + * single element. + * + * Return: number of elements in the array on success, -EOVERFLOW if + * @actual_len is greater than the expected length, -EMSGSIZE if + * @actual_len is not a multiple of a single element. + */ +#define es58x_msg_num_element(dev, msg, actual_len) \ +({ \ + size_t __elem_len = sizeof((msg)[0]) + __must_be_array(msg); \ + __es58x_msg_num_element(dev, __stringify(msg), actual_len, \ + sizeof(msg), __elem_len); \ +}) + +/** + * es58x_priv() - Get the priv member and cast it to struct es58x_priv. + * @netdev: CAN network device. + * + * Return: ES58X device. + */ +static inline struct es58x_priv *es58x_priv(struct net_device *netdev) +{ + return (struct es58x_priv *)netdev_priv(netdev); +} + +/** + * ES58X_SIZEOF_URB_CMD() - Calculate the maximum length of an urb + * command for a given message field name. + * @es58x_urb_cmd_type: type (either "struct es581_4_urb_cmd" or + * "struct es58x_fd_urb_cmd"). + * @msg_field: name of the message field. + * + * Must be a macro in order to accept the different command types as + * an input. + * + * Return: length of the urb command. + */ +#define ES58X_SIZEOF_URB_CMD(es58x_urb_cmd_type, msg_field) \ + (offsetof(es58x_urb_cmd_type, raw_msg) \ + + sizeof_field(es58x_urb_cmd_type, msg_field) \ + + sizeof_field(es58x_urb_cmd_type, \ + reserved_for_crc16_do_not_use)) + +/** + * es58x_get_urb_cmd_len() - Calculate the actual length of an urb + * command for a given message length. + * @es58x_dev: ES58X device. + * @msg_len: Length of the message. + * + * Add the header and CRC lengths to the message length. + * + * Return: length of the urb command. + */ +static inline size_t es58x_get_urb_cmd_len(struct es58x_device *es58x_dev, + u16 msg_len) +{ + return es58x_dev->param->urb_cmd_header_len + msg_len + sizeof(u16); +} + +/** + * es58x_get_netdev() - Get the network device. + * @es58x_dev: ES58X device. + * @channel_no: The channel number as advertised in the urb command. + * @channel_idx_offset: Some of the ES58x starts channel numbering + * from 0 (ES58X FD), others from 1 (ES581.4). + * @netdev: CAN network device. + * + * Do a sanity check on the index provided by the device. + * + * Return: zero on success, -ECHRNG if the received channel number is + * out of range and -ENODEV if the network device is not yet + * configured. + */ +static inline int es58x_get_netdev(struct es58x_device *es58x_dev, + int channel_no, int channel_idx_offset, + struct net_device **netdev) +{ + int channel_idx = channel_no - channel_idx_offset; + + *netdev = NULL; + if (channel_idx < 0 || channel_idx >= es58x_dev->num_can_ch) + return -ECHRNG; + + *netdev = es58x_dev->netdev[channel_idx]; + if (!netdev || !netif_device_present(*netdev)) + return -ENODEV; + + return 0; +} + +/** + * es58x_get_raw_can_id() - Get the CAN ID. + * @cf: CAN frame. + * + * Mask the CAN ID in order to only keep the significant bits. + * + * Return: the raw value of the CAN ID. + */ +static inline int es58x_get_raw_can_id(const struct can_frame *cf) +{ + if (cf->can_id & CAN_EFF_FLAG) + return cf->can_id & CAN_EFF_MASK; + else + return cf->can_id & CAN_SFF_MASK; +} + +/** + * es58x_get_flags() - Get the CAN flags. + * @skb: socket buffer of a CAN message. + * + * Return: the CAN flag as an enum es58x_flag. + */ +static inline enum es58x_flag es58x_get_flags(const struct sk_buff *skb) +{ + struct canfd_frame *cf = (struct canfd_frame *)skb->data; + enum es58x_flag es58x_flags = 0; + + if (cf->can_id & CAN_EFF_FLAG) + es58x_flags |= ES58X_FLAG_EFF; + + if (can_is_canfd_skb(skb)) { + es58x_flags |= ES58X_FLAG_FD_DATA; + if (cf->flags & CANFD_BRS) + es58x_flags |= ES58X_FLAG_FD_BRS; + if (cf->flags & CANFD_ESI) + es58x_flags |= ES58X_FLAG_FD_ESI; + } else if (cf->can_id & CAN_RTR_FLAG) + /* Remote frames are only defined in Classical CAN frames */ + es58x_flags |= ES58X_FLAG_RTR; + + return es58x_flags; +} + +int es58x_can_get_echo_skb(struct net_device *netdev, u32 packet_idx, + u64 *tstamps, unsigned int pkts); +int es58x_tx_ack_msg(struct net_device *netdev, u16 tx_free_entries, + enum es58x_ret_u32 rx_cmd_ret_u32); +int es58x_rx_can_msg(struct net_device *netdev, u64 timestamp, const u8 *data, + canid_t can_id, enum es58x_flag es58x_flags, u8 dlc); +int es58x_rx_err_msg(struct net_device *netdev, enum es58x_err error, + enum es58x_event event, u64 timestamp); +void es58x_rx_timestamp(struct es58x_device *es58x_dev, u64 timestamp); +int es58x_rx_cmd_ret_u8(struct device *dev, enum es58x_ret_type cmd_ret_type, + enum es58x_ret_u8 rx_cmd_ret_u8); +int es58x_rx_cmd_ret_u32(struct net_device *netdev, + enum es58x_ret_type cmd_ret_type, + enum es58x_ret_u32 rx_cmd_ret_u32); +int es58x_send_msg(struct es58x_device *es58x_dev, u8 cmd_type, u8 cmd_id, + const void *msg, u16 cmd_len, int channel_idx); + +extern const struct es58x_parameters es581_4_param; +extern const struct es58x_operators es581_4_ops; + +extern const struct es58x_parameters es58x_fd_param; +extern const struct es58x_operators es58x_fd_ops; + +#endif /* __ES58X_COMMON_H__ */ |