[PATCH v2 1/4] mfd: cros_ec: Add cros_ec_cmd_xfer_status helper

Brian Norris
2016-06-03T01:22:00Z

From: Tomeu Vizoso <tomeu.vizoso@collabora.com>

So that callers of cros_ec_cmd_xfer don't have to repeat boilerplate
code when checking for errors from the EC side.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
---
v2: no change

drivers/platform/chrome/cros_ec_proto.c | 15 +++++++++++++++
include/linux/mfd/cros_ec.h | 18 ++++++++++++++++++
2 files changed, 33 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index b6e161f71b26..ecc544c728f0 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -380,3 +380,18 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
return ret;
}
EXPORT_SYMBOL(cros_ec_cmd_xfer);
+
+int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *msg)
+{
+ int ret;
+
+ ret = cros_ec_cmd_xfer(ec_dev, msg);
+ if (ret < 0)
+ dev_err(ec_dev->dev, "Command xfer error (err:%d)\n", ret);
+ else if (msg->result != EC_RES_SUCCESS)
+ return -EECRESULT - msg->result;
+
+ return ret;
+}
+EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
index 64184d27e3cd..b1e48dfbf50a 100644
--- a/include/linux/mfd/cros_ec.h
+++ b/include/linux/mfd/cros_ec.h
@@ -40,6 +40,9 @@
#define EC_MAX_REQUEST_OVERHEAD 1
#define EC_MAX_RESPONSE_OVERHEAD 2

+/* ec_command return value for non-success result from EC */
+#define EECRESULT 1000
+
/*
* Command interface between EC and AP, for LPC, I2C and SPI interfaces.
*/
@@ -226,6 +229,21 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg);

/**
+ * cros_ec_cmd_xfer_status - Send a command to the ChromeOS EC
+ *
+ * This function is identical to cros_ec_cmd_xfer, except it returns succes
+ * status only if both the command was transmitted successfully and the EC
+ * replied with success status. It's not necessary to check msg->result when
+ * using this function.
+ *
+ * @ec_dev: EC device
+ * @msg: Message to write
+ * @return: Num. of bytes transferred on success, <0 on failure
+ */
+int cros_ec_cmd_xfer_status(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.
--
2.8.0.rc3.226.g39d4020