[PATCH 4.4 078/113] mfd: cros_ec: Add cros_ec_cmd_xfer_status() helper

Greg Kroah-Hartman
2016-09-05T16:54:54Z

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

commit 9798ac6d32c1a32d6d92d853ff507d2d39c4300c upstream.

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>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/platform/chrome/cros_ec_proto.c | 17 +++++++++++++++++
include/linux/mfd/cros_ec.h | 15 +++++++++++++++
2 files changed, 32 insertions(+)

--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -380,3 +380,20 @@ int cros_ec_cmd_xfer(struct cros_ec_devi
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) {
+ dev_dbg(ec_dev->dev, "Command result (err: %d)\n", msg->result);
+ return -EPROTO;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
--- a/include/linux/mfd/cros_ec.h
+++ b/include/linux/mfd/cros_ec.h
@@ -224,6 +224,21 @@ int cros_ec_cmd_xfer(struct cros_ec_devi
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 success
+ * 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.