mfd: cros_ec: stop calling ->cmd_xfer() directly

Instead of having users of the ChromeOS EC call the interface-specific
cmd_xfer() callback directly, introduce a central cros_ec_cmd_xfer()
to use instead.  This will allow us to put all the locking and retry
logic in one place instead of duplicating it across the different
drivers.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

4 files changed, 27 insertions, 8 deletions

diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
index 05e033c98115..43be23dfb115 100644
--- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c
+++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
@@ -227,7 +227,7 @@ static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[],
         msg.indata = response;
         msg.insize = response_len;
 
-        result = bus->ec->cmd_xfer(bus->ec, &msg);
+        result = cros_ec_cmd_xfer(bus->ec, &msg);
         if (result < 0)
                 goto exit;
 
diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c
index 791781ade4e7..93111d1aa617 100644
--- a/drivers/input/keyboard/cros_ec_keyb.c
+++ b/drivers/input/keyboard/cros_ec_keyb.c
@@ -182,7 +182,7 @@ static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
                 .insize = ckdev->cols,
         };
 
-        return ckdev->ec->cmd_xfer(ckdev->ec, &msg);
+        return cros_ec_cmd_xfer(ckdev->ec, &msg);
 }
 
 static irqreturn_t cros_ec_keyb_irq(int irq, void *data)
diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c
index 4873f9c50452..a9faebdcfa14 100644
--- a/drivers/mfd/cros_ec.c
+++ b/drivers/mfd/cros_ec.c
@@ -62,6 +62,13 @@ int cros_ec_check_result(struct cros_ec_device *ec_dev,
 }
 EXPORT_SYMBOL(cros_ec_check_result);
 
+int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
+                     struct cros_ec_command *msg)
+{
+        return ec_dev->cmd_xfer(ec_dev, msg);
+}
+EXPORT_SYMBOL(cros_ec_cmd_xfer);
+
 static const struct mfd_cell cros_devs[] = {
         {
                 .name = "cros-ec-keyb",
diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
index fcbe9d129a9d..0e166b92f5b4 100644
--- a/include/linux/mfd/cros_ec.h
+++ b/include/linux/mfd/cros_ec.h
@@ -62,10 +62,6 @@ struct cros_ec_command {
  * @dev: Device pointer
  * @was_wake_device: true if this device was set to wake the system from
  * sleep at the last suspend
- * @cmd_xfer: send command to EC and get response
- *     Returns the number of bytes received if the communication succeeded, but
- *     that doesn't mean the EC was happy with the command. The caller
- *     should check msg.result for the EC's result code.
  *
  * @priv: Private data
  * @irq: Interrupt to use
@@ -82,6 +78,10 @@ struct cros_ec_command {
  * @dout_size: size of dout buffer to allocate (zero to use static dout)
  * @parent: pointer to parent device (e.g. i2c or spi device)
  * @wake_enabled: true if this device can wake the system from sleep
+ * @cmd_xfer: send command to EC and get response
+ *     Returns the number of bytes received if the communication succeeded, but
+ *     that doesn't mean the EC was happy with the command. The caller
+ *     should check msg.result for the EC's result code.
  * @lock: one transaction at a time
  */
 struct cros_ec_device {
@@ -92,8 +92,6 @@ struct cros_ec_device {
         struct device *dev;
         bool was_wake_device;
         struct class *cros_class;
-        int (*cmd_xfer)(struct cros_ec_device *ec,
-                        struct cros_ec_command *msg);
 
         /* These are used to implement the platform-specific interface */
         void *priv;
@@ -104,6 +102,8 @@ struct cros_ec_device {
         int dout_size;
         struct device *parent;
         bool wake_enabled;
+        int (*cmd_xfer)(struct cros_ec_device *ec,
+                        struct cros_ec_command *msg);
         struct mutex lock;
 };
 
@@ -153,6 +153,18 @@ int cros_ec_check_result(struct cros_ec_device *ec_dev,
                          struct cros_ec_command *msg);
 
 /**
+ * cros_ec_cmd_xfer - Send a command to the ChromeOS EC
+ *
+ * Call this to send a command to the ChromeOS EC.  This should be used
+ * instead of calling the EC's cmd_xfer() callback directly.
+ *
+ * @ec_dev: EC device
+ * @msg: Message to write
+ */
+int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
+                     struct cros_ec_command *msg);
+
+/**
  * cros_ec_remove - Remove a ChromeOS EC
  *
  * Call this to deregister a ChromeOS EC, then clean up any private data.