diff options
Diffstat (limited to 'drivers/mfd/nct6694.c')
| -rw-r--r-- | drivers/mfd/nct6694.c | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/drivers/mfd/nct6694.c b/drivers/mfd/nct6694.c new file mode 100644 index 000000000000..308b2fda3055 --- /dev/null +++ b/drivers/mfd/nct6694.c @@ -0,0 +1,388 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2025 Nuvoton Technology Corp. + * + * Nuvoton NCT6694 core driver using USB interface to provide + * access to the NCT6694 hardware monitoring and control features. + * + * The NCT6694 is an integrated controller that provides GPIO, I2C, + * CAN, WDT, HWMON and RTC management. + */ + +#include <linux/bits.h> +#include <linux/interrupt.h> +#include <linux/idr.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/mfd/core.h> +#include <linux/mfd/nct6694.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/usb.h> + +static const struct mfd_cell nct6694_devs[] = { + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + MFD_CELL_NAME("nct6694-gpio"), + + MFD_CELL_NAME("nct6694-i2c"), + MFD_CELL_NAME("nct6694-i2c"), + MFD_CELL_NAME("nct6694-i2c"), + MFD_CELL_NAME("nct6694-i2c"), + MFD_CELL_NAME("nct6694-i2c"), + MFD_CELL_NAME("nct6694-i2c"), + + MFD_CELL_NAME("nct6694-canfd"), + MFD_CELL_NAME("nct6694-canfd"), + + MFD_CELL_NAME("nct6694-wdt"), + MFD_CELL_NAME("nct6694-wdt"), + + MFD_CELL_NAME("nct6694-hwmon"), + + MFD_CELL_NAME("nct6694-rtc"), +}; + +static int nct6694_response_err_handling(struct nct6694 *nct6694, unsigned char err_status) +{ + switch (err_status) { + case NCT6694_NO_ERROR: + return 0; + case NCT6694_NOT_SUPPORT_ERROR: + dev_err(nct6694->dev, "Command is not supported!\n"); + break; + case NCT6694_NO_RESPONSE_ERROR: + dev_warn(nct6694->dev, "Command received no response!\n"); + break; + case NCT6694_TIMEOUT_ERROR: + dev_warn(nct6694->dev, "Command timed out!\n"); + break; + case NCT6694_PENDING: + dev_err(nct6694->dev, "Command is pending!\n"); + break; + default: + return -EINVAL; + } + + return -EIO; +} + +/** + * nct6694_read_msg() - Read message from NCT6694 device + * @nct6694: NCT6694 device pointer + * @cmd_hd: command header structure + * @buf: buffer to store the response data + * + * Sends a command to the NCT6694 device and reads the response. + * The command header is specified in @cmd_hd, and the response + * data is stored in @buf. + * + * Return: Negative value on error or 0 on success. + */ +int nct6694_read_msg(struct nct6694 *nct6694, const struct nct6694_cmd_header *cmd_hd, void *buf) +{ + union nct6694_usb_msg *msg = nct6694->usb_msg; + struct usb_device *udev = nct6694->udev; + int tx_len, rx_len, ret; + + guard(mutex)(&nct6694->access_lock); + + memcpy(&msg->cmd_header, cmd_hd, sizeof(*cmd_hd)); + msg->cmd_header.hctrl = NCT6694_HCTRL_GET; + + /* Send command packet to USB device */ + ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, NCT6694_BULK_OUT_EP), &msg->cmd_header, + sizeof(*msg), &tx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + /* Receive response packet from USB device */ + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, NCT6694_BULK_IN_EP), &msg->response_header, + sizeof(*msg), &rx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + /* Receive data packet from USB device */ + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, NCT6694_BULK_IN_EP), buf, + le16_to_cpu(cmd_hd->len), &rx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + if (rx_len != le16_to_cpu(cmd_hd->len)) { + dev_err(nct6694->dev, "Expected received length %d, but got %d\n", + le16_to_cpu(cmd_hd->len), rx_len); + return -EIO; + } + + return nct6694_response_err_handling(nct6694, msg->response_header.sts); +} +EXPORT_SYMBOL_GPL(nct6694_read_msg); + +/** + * nct6694_write_msg() - Write message to NCT6694 device + * @nct6694: NCT6694 device pointer + * @cmd_hd: command header structure + * @buf: buffer containing the data to be sent + * + * Sends a command to the NCT6694 device and writes the data + * from @buf. The command header is specified in @cmd_hd. + * + * Return: Negative value on error or 0 on success. + */ +int nct6694_write_msg(struct nct6694 *nct6694, const struct nct6694_cmd_header *cmd_hd, void *buf) +{ + union nct6694_usb_msg *msg = nct6694->usb_msg; + struct usb_device *udev = nct6694->udev; + int tx_len, rx_len, ret; + + guard(mutex)(&nct6694->access_lock); + + memcpy(&msg->cmd_header, cmd_hd, sizeof(*cmd_hd)); + msg->cmd_header.hctrl = NCT6694_HCTRL_SET; + + /* Send command packet to USB device */ + ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, NCT6694_BULK_OUT_EP), &msg->cmd_header, + sizeof(*msg), &tx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + /* Send data packet to USB device */ + ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, NCT6694_BULK_OUT_EP), buf, + le16_to_cpu(cmd_hd->len), &tx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + /* Receive response packet from USB device */ + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, NCT6694_BULK_IN_EP), &msg->response_header, + sizeof(*msg), &rx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + /* Receive data packet from USB device */ + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, NCT6694_BULK_IN_EP), buf, + le16_to_cpu(cmd_hd->len), &rx_len, NCT6694_URB_TIMEOUT); + if (ret) + return ret; + + if (rx_len != le16_to_cpu(cmd_hd->len)) { + dev_err(nct6694->dev, "Expected transmitted length %d, but got %d\n", + le16_to_cpu(cmd_hd->len), rx_len); + return -EIO; + } + + return nct6694_response_err_handling(nct6694, msg->response_header.sts); +} +EXPORT_SYMBOL_GPL(nct6694_write_msg); + +static void usb_int_callback(struct urb *urb) +{ + struct nct6694 *nct6694 = urb->context; + __le32 *status_le = urb->transfer_buffer; + u32 int_status; + int ret; + + switch (urb->status) { + case 0: + break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + return; + default: + goto resubmit; + } + + int_status = le32_to_cpu(*status_le); + + while (int_status) { + int irq = __ffs(int_status); + + generic_handle_irq_safe(irq_find_mapping(nct6694->domain, irq)); + int_status &= ~BIT(irq); + } + +resubmit: + ret = usb_submit_urb(urb, GFP_ATOMIC); + if (ret) + dev_warn(nct6694->dev, "Failed to resubmit urb, status %pe", ERR_PTR(ret)); +} + +static void nct6694_irq_enable(struct irq_data *data) +{ + struct nct6694 *nct6694 = irq_data_get_irq_chip_data(data); + irq_hw_number_t hwirq = irqd_to_hwirq(data); + + guard(spinlock_irqsave)(&nct6694->irq_lock); + + nct6694->irq_enable |= BIT(hwirq); +} + +static void nct6694_irq_disable(struct irq_data *data) +{ + struct nct6694 *nct6694 = irq_data_get_irq_chip_data(data); + irq_hw_number_t hwirq = irqd_to_hwirq(data); + + guard(spinlock_irqsave)(&nct6694->irq_lock); + + nct6694->irq_enable &= ~BIT(hwirq); +} + +static const struct irq_chip nct6694_irq_chip = { + .name = "nct6694-irq", + .flags = IRQCHIP_SKIP_SET_WAKE, + .irq_enable = nct6694_irq_enable, + .irq_disable = nct6694_irq_disable, +}; + +static int nct6694_irq_domain_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) +{ + struct nct6694 *nct6694 = d->host_data; + + irq_set_chip_data(irq, nct6694); + irq_set_chip_and_handler(irq, &nct6694_irq_chip, handle_simple_irq); + + return 0; +} + +static void nct6694_irq_domain_unmap(struct irq_domain *d, unsigned int irq) +{ + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); +} + +static const struct irq_domain_ops nct6694_irq_domain_ops = { + .map = nct6694_irq_domain_map, + .unmap = nct6694_irq_domain_unmap, +}; + +static int nct6694_usb_probe(struct usb_interface *iface, + const struct usb_device_id *id) +{ + struct usb_device *udev = interface_to_usbdev(iface); + struct usb_endpoint_descriptor *int_endpoint; + struct usb_host_interface *interface; + struct device *dev = &iface->dev; + struct nct6694 *nct6694; + int ret; + + nct6694 = devm_kzalloc(dev, sizeof(*nct6694), GFP_KERNEL); + if (!nct6694) + return -ENOMEM; + + nct6694->usb_msg = devm_kzalloc(dev, sizeof(union nct6694_usb_msg), GFP_KERNEL); + if (!nct6694->usb_msg) + return -ENOMEM; + + nct6694->int_buffer = devm_kzalloc(dev, sizeof(*nct6694->int_buffer), GFP_KERNEL); + if (!nct6694->int_buffer) + return -ENOMEM; + + nct6694->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); + if (!nct6694->int_in_urb) + return -ENOMEM; + + nct6694->domain = irq_domain_create_simple(NULL, NCT6694_NR_IRQS, 0, + &nct6694_irq_domain_ops, + nct6694); + if (!nct6694->domain) { + ret = -ENODEV; + goto err_urb; + } + + nct6694->dev = dev; + nct6694->udev = udev; + + ida_init(&nct6694->gpio_ida); + ida_init(&nct6694->i2c_ida); + ida_init(&nct6694->canfd_ida); + ida_init(&nct6694->wdt_ida); + + spin_lock_init(&nct6694->irq_lock); + + ret = devm_mutex_init(dev, &nct6694->access_lock); + if (ret) + goto err_ida; + + interface = iface->cur_altsetting; + + int_endpoint = &interface->endpoint[0].desc; + if (!usb_endpoint_is_int_in(int_endpoint)) { + ret = -ENODEV; + goto err_ida; + } + + usb_fill_int_urb(nct6694->int_in_urb, udev, usb_rcvintpipe(udev, NCT6694_INT_IN_EP), + nct6694->int_buffer, sizeof(*nct6694->int_buffer), usb_int_callback, + nct6694, int_endpoint->bInterval); + + ret = usb_submit_urb(nct6694->int_in_urb, GFP_KERNEL); + if (ret) + goto err_ida; + + usb_set_intfdata(iface, nct6694); + + ret = mfd_add_hotplug_devices(dev, nct6694_devs, ARRAY_SIZE(nct6694_devs)); + if (ret) + goto err_mfd; + + return 0; + +err_mfd: + usb_kill_urb(nct6694->int_in_urb); +err_ida: + ida_destroy(&nct6694->wdt_ida); + ida_destroy(&nct6694->canfd_ida); + ida_destroy(&nct6694->i2c_ida); + ida_destroy(&nct6694->gpio_ida); + irq_domain_remove(nct6694->domain); +err_urb: + usb_free_urb(nct6694->int_in_urb); + return ret; +} + +static void nct6694_usb_disconnect(struct usb_interface *iface) +{ + struct nct6694 *nct6694 = usb_get_intfdata(iface); + + mfd_remove_devices(nct6694->dev); + usb_kill_urb(nct6694->int_in_urb); + ida_destroy(&nct6694->wdt_ida); + ida_destroy(&nct6694->canfd_ida); + ida_destroy(&nct6694->i2c_ida); + ida_destroy(&nct6694->gpio_ida); + irq_domain_remove(nct6694->domain); + usb_free_urb(nct6694->int_in_urb); +} + +static const struct usb_device_id nct6694_ids[] = { + { USB_DEVICE_AND_INTERFACE_INFO(NCT6694_VENDOR_ID, NCT6694_PRODUCT_ID, 0xFF, 0x00, 0x00) }, + { } +}; +MODULE_DEVICE_TABLE(usb, nct6694_ids); + +static struct usb_driver nct6694_usb_driver = { + .name = "nct6694", + .id_table = nct6694_ids, + .probe = nct6694_usb_probe, + .disconnect = nct6694_usb_disconnect, +}; +module_usb_driver(nct6694_usb_driver); + +MODULE_DESCRIPTION("Nuvoton NCT6694 core driver"); +MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>"); +MODULE_LICENSE("GPL"); |