mfd: cros_ec: Use a zero-length array for command data

[cascardo/linux.git] / drivers / mfd / cros_ec_spi.c

diff --git a/drivers/mfd/cros_ec_spi.c b/drivers/mfd/cros_ec_spi.c
index 588c700..573730f 100644 (file)
--- 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_cmd_xfer_spi 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,
@@ -226,13 +230,6 @@ static int cros_ec_cmd_xfer_spi(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);
 
@@ -302,7 +299,7 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
        for (i = 0; i < len; i++) {
                sum += ptr[i + 2];
                if (ec_msg->insize)
-                       ec_msg->indata[i] = ptr[i + 2];
+                       ec_msg->data[i] = ptr[i + 2];
        }
        sum &= 0xff;
 
@@ -318,7 +315,9 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
 
        ret = len;
 exit:
-       mutex_unlock(&ec_spi->lock);
+       if (ec_msg->command == EC_CMD_REBOOT_EC)
+               msleep(EC_REBOOT_DELAY_MS);
+
        return ret;
 }
 
@@ -350,7 +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;
@@ -365,7 +363,6 @@ static int cros_ec_spi_probe(struct spi_device *spi)
        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;
        ec_dev->din_size = EC_MSG_BYTES + EC_MSG_PREAMBLE_COUNT;
        ec_dev->dout_size = EC_MSG_BYTES;