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).
Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_dev.c | 53 +++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)
diff --git a/drivers/platform/chrome/cros_ec_dev.c b/drivers/platform/chrome/cros_ec_dev.c
index cf6c4f0..d64bf05 100644
--- a/drivers/platform/chrome/cros_ec_dev.c
+++ b/drivers/platform/chrome/cros_ec_dev.c
@@ -388,6 +388,56 @@ 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];
+
+ /*
+ * 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 int ec_device_probe(struct platform_device *pdev)
{
int retval = -ENOMEM;
@@ -435,6 +485,9 @@ 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);
/* Take control of the lightbar from the EC. */
lb_manual_suspend_ctrl(ec, 1);
--
2.7.4
--
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