diff options
Diffstat (limited to 'drivers/mfd/cros_ec_spi.c')
-rw-r--r-- | drivers/mfd/cros_ec_spi.c | 74 |
1 files changed, 34 insertions, 40 deletions
diff --git a/drivers/mfd/cros_ec_spi.c b/drivers/mfd/cros_ec_spi.c index 8c1c7cc373f8..bf6e08e8013e 100644 --- a/drivers/mfd/cros_ec_spi.c +++ b/drivers/mfd/cros_ec_spi.c @@ -65,6 +65,12 @@ */ #define EC_SPI_RECOVERY_TIME_NS (200 * 1000) +/* + * The EC is unresponsive for a time after a reboot command. Add a + * simple delay to make sure that the bus stays locked. + */ +#define EC_REBOOT_DELAY_MS 50 + /** * struct cros_ec_spi - information about a SPI-connected EC * @@ -73,13 +79,11 @@ * if no record * @end_of_msg_delay: used to set the delay_usecs on the spi_transfer that * is sent when we want to turn off CS at the end of a transaction. - * @lock: mutex to ensure only one user of cros_ec_command_spi_xfer at a time */ struct cros_ec_spi { struct spi_device *spi; s64 last_transfer_ns; unsigned int end_of_msg_delay; - struct mutex lock; }; static void debug_packet(struct device *dev, const char *name, u8 *ptr, @@ -210,13 +214,13 @@ static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev, } /** - * cros_ec_command_spi_xfer - Transfer a message over SPI and receive the reply + * cros_ec_cmd_xfer_spi - Transfer a message over SPI and receive the reply * * @ec_dev: ChromeOS EC device * @ec_msg: Message to transfer */ -static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, - struct cros_ec_msg *ec_msg) +static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev, + struct cros_ec_command *ec_msg) { struct cros_ec_spi *ec_spi = ec_dev->priv; struct spi_transfer trans; @@ -226,13 +230,6 @@ static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, int sum; int ret = 0, final_ret; - /* - * We have the shared ec_dev buffer plus we do lots of separate spi_sync - * calls, so we need to make sure only one person is using this at a - * time. - */ - mutex_lock(&ec_spi->lock); - len = cros_ec_prepare_tx(ec_dev, ec_msg); dev_dbg(ec_dev->dev, "prepared, len=%d\n", len); @@ -258,23 +255,19 @@ static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, /* Get the response */ if (!ret) { ret = cros_ec_spi_receive_response(ec_dev, - ec_msg->in_len + EC_MSG_TX_PROTO_BYTES); + ec_msg->insize + EC_MSG_TX_PROTO_BYTES); } else { dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret); } - /* turn off CS */ + /* + * Turn off CS, possibly adding a delay to ensure the rising edge + * doesn't come too soon after the end of the data. + */ spi_message_init(&msg); - - if (ec_spi->end_of_msg_delay) { - /* - * Add delay for last transaction, to ensure the rising edge - * doesn't come too soon after the end of the data. - */ - memset(&trans, 0, sizeof(trans)); - trans.delay_usecs = ec_spi->end_of_msg_delay; - spi_message_add_tail(&trans, &msg); - } + memset(&trans, 0, sizeof(trans)); + trans.delay_usecs = ec_spi->end_of_msg_delay; + spi_message_add_tail(&trans, &msg); final_ret = spi_sync(ec_spi->spi, &msg); ec_spi->last_transfer_ns = ktime_get_ns(); @@ -285,20 +278,19 @@ static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, goto exit; } - /* check response error code */ ptr = ec_dev->din; - if (ptr[0]) { - dev_warn(ec_dev->dev, "command 0x%02x returned an error %d\n", - ec_msg->cmd, ptr[0]); - debug_packet(ec_dev->dev, "in_err", ptr, len); - ret = -EINVAL; + + /* check response error code */ + ec_msg->result = ptr[0]; + ret = cros_ec_check_result(ec_dev, ec_msg); + if (ret) goto exit; - } + len = ptr[1]; sum = ptr[0] + ptr[1]; - if (len > ec_msg->in_len) { + if (len > ec_msg->insize) { dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)", - len, ec_msg->in_len); + len, ec_msg->insize); ret = -ENOSPC; goto exit; } @@ -306,8 +298,8 @@ static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, /* copy response packet payload and compute checksum */ for (i = 0; i < len; i++) { sum += ptr[i + 2]; - if (ec_msg->in_len) - ec_msg->in_buf[i] = ptr[i + 2]; + if (ec_msg->insize) + ec_msg->indata[i] = ptr[i + 2]; } sum &= 0xff; @@ -321,9 +313,11 @@ static int cros_ec_command_spi_xfer(struct cros_ec_device *ec_dev, goto exit; } - ret = 0; + ret = len; exit: - mutex_unlock(&ec_spi->lock); + if (ec_msg->command == EC_CMD_REBOOT_EC) + msleep(EC_REBOOT_DELAY_MS); + return ret; } @@ -355,7 +349,6 @@ static int cros_ec_spi_probe(struct spi_device *spi) if (ec_spi == NULL) return -ENOMEM; ec_spi->spi = spi; - mutex_init(&ec_spi->lock); ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL); if (!ec_dev) return -ENOMEM; @@ -364,11 +357,10 @@ static int cros_ec_spi_probe(struct spi_device *spi) cros_ec_spi_dt_probe(ec_spi, dev); spi_set_drvdata(spi, ec_dev); - ec_dev->name = "SPI"; ec_dev->dev = dev; ec_dev->priv = ec_spi; ec_dev->irq = spi->irq; - ec_dev->command_xfer = cros_ec_command_spi_xfer; + ec_dev->cmd_xfer = cros_ec_cmd_xfer_spi; ec_dev->ec_name = ec_spi->spi->modalias; ec_dev->phys_name = dev_name(&ec_spi->spi->dev); ec_dev->parent = &ec_spi->spi->dev; @@ -381,6 +373,8 @@ static int cros_ec_spi_probe(struct spi_device *spi) return err; } + device_init_wakeup(&spi->dev, true); + return 0; } |