On Mon, Feb 19, 2018 at 2:46 PM, Enric Balletbo i Serra
<enric.balle...@collabora.com> wrote:
> With this patch, the cros_ec_ctl driver will register the legacy
> accelerometer driver (named cros_ec_accel_legacy) if it fails to
> register sensors through the usual path cros_ec_sensors_register().
> This legacy device is present on Chromebook devices with older EC
> firmware only supporting deprecated EC commands (Glimmer based devices).
>
> Tested-by: Gwendal Grignou <gwen...@chromium.org>
> Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com>
Reviewed-by: Gwendal Grignou <gwen...@chromium.org>
> ---
> drivers/mfd/cros_ec_dev.c | 60
> +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 60 insertions(+)
>
> diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
> index e0c604ab380f..fc98e0564061 100644
> --- a/drivers/mfd/cros_ec_dev.c
> +++ b/drivers/mfd/cros_ec_dev.c
> @@ -389,6 +389,63 @@ static void cros_ec_sensors_register(struct cros_ec_dev
> *ec)
> kfree(msg);
> }
>
> +#define CROS_EC_SENSOR_LEGACY_NUM 2
> +static struct mfd_cell cros_ec_accel_legacy_cells[CROS_EC_SENSOR_LEGACY_NUM];
> +
> +static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
> +{
> + struct cros_ec_device *ec_dev = ec->ec_dev;
> + u8 status;
> + int i, ret;
> + struct cros_ec_sensor_platform
> + sensor_platforms[CROS_EC_SENSOR_LEGACY_NUM];
> +
> + /*
> + * EC that need legacy support are the main EC, directly connected to
> + * the AP.
> + */
> + if (ec->cmd_offset != 0)
> + return;
> +
> + /*
> + * Check if EC supports direct memory reads and if EC has
> + * accelerometers.
> + */
> + if (!ec_dev->cmd_readmem)
> + return;
> +
> + ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1, &status);
> + if (ret < 0) {
> + dev_warn(ec->dev, "EC does not support direct reads.\n");
> + return;
> + }
> +
> + /* Check if EC has accelerometers. */
> + if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
> + dev_info(ec->dev, "EC does not have accelerometers.\n");
> + return;
> + }
> +
> + /*
> + * Register 2 accelerometers
> + */
> + for (i = 0; i < CROS_EC_SENSOR_LEGACY_NUM; i++) {
> + cros_ec_accel_legacy_cells[i].name = "cros-ec-accel-legacy";
> + sensor_platforms[i].sensor_num = i;
> + cros_ec_accel_legacy_cells[i].id = i;
> + cros_ec_accel_legacy_cells[i].platform_data =
> + &sensor_platforms[i];
> + cros_ec_accel_legacy_cells[i].pdata_size =
> + sizeof(struct cros_ec_sensor_platform);
> + }
> + ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
> + cros_ec_accel_legacy_cells,
> + CROS_EC_SENSOR_LEGACY_NUM,
> + NULL, 0, NULL);
> + if (ret)
> + dev_err(ec_dev->dev, "failed to add EC sensors\n");
> +}
> +
> static const struct mfd_cell cros_ec_rtc_cell = {
> .name = "cros-ec-rtc",
> };
> @@ -440,6 +497,9 @@ static int ec_device_probe(struct platform_device *pdev)
> /* check whether this EC is a sensor hub. */
> if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
> cros_ec_sensors_register(ec);
> + else
> + /* Workaroud for older EC firmware */
> + cros_ec_accel_legacy_register(ec);
>
> /* check whether this EC instance has RTC host command support */
> if (cros_ec_check_features(ec, EC_FEATURE_RTC)) {
> --
> 2.16.1
>
