diff options
| author | Andrew Bresticker <abrestic@chromium.org> | 2014-09-18 17:18:58 +0200 |
|---|---|---|
| committer | Lee Jones <lee.jones@linaro.org> | 2014-10-06 22:30:16 +0200 |
| commit | d86c21fd31114e3ef9fae64be335c76aa22859dc (patch) | |
| tree | 5f376a7091afbdb813e2ad25407a7b0026d08118 /drivers | |
| parent | i2c: i2c-cros-ec-tunnel: Set retries to 3 (diff) | |
| download | linux-d86c21fd31114e3ef9fae64be335c76aa22859dc.tar.xz linux-d86c21fd31114e3ef9fae64be335c76aa22859dc.zip | |
mfd: cros_ec: wait for completion of commands that return IN_PROGRESS
When an EC command returns EC_RES_IN_PROGRESS, we need to query
the state of the EC until it indicates that it is no longer busy.
Do this in cros_ec_cmd_xfer() under the EC's mutex so that other
commands (e.g. keyboard, I2C passtru) aren't issued to the EC while
it is working on the in-progress command.
The 10 milliseconds delay and the number of retries are the values
that were used by the flashrom tool when retrying commands.
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>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mfd/cros_ec.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c index c53804a1451d..fc0c81ef04ff 100644 --- a/drivers/mfd/cros_ec.c +++ b/drivers/mfd/cros_ec.c @@ -23,6 +23,9 @@ #include <linux/mfd/core.h> #include <linux/mfd/cros_ec.h> #include <linux/mfd/cros_ec_commands.h> +#include <linux/delay.h> + +#define EC_COMMAND_RETRIES 50 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev, struct cros_ec_command *msg) @@ -69,6 +72,36 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, mutex_lock(&ec_dev->lock); ret = ec_dev->cmd_xfer(ec_dev, msg); + if (msg->result == EC_RES_IN_PROGRESS) { + int i; + struct cros_ec_command status_msg; + struct ec_response_get_comms_status status; + + status_msg.version = 0; + status_msg.command = EC_CMD_GET_COMMS_STATUS; + status_msg.outdata = NULL; + status_msg.outsize = 0; + status_msg.indata = (uint8_t *)&status; + status_msg.insize = sizeof(status); + + /* + * Query the EC's status until it's no longer busy or + * we encounter an error. + */ + for (i = 0; i < EC_COMMAND_RETRIES; i++) { + usleep_range(10000, 11000); + + ret = ec_dev->cmd_xfer(ec_dev, &status_msg); + if (ret < 0) + break; + + msg->result = status_msg.result; + if (status_msg.result != EC_RES_SUCCESS) + break; + if (!(status.flags & EC_COMMS_STATUS_PROCESSING)) + break; + } + } mutex_unlock(&ec_dev->lock); return ret; |