[PATCH v7 1/2] mfd: cros_ec: Register cros_ec_lid_angle driver when presented

[Gwendal Grignou]

Register driver when EC indicates has precise lid angle calculation code
running.
Fix incorrect extra resource allocation in cros_ec_sensors_register().

Signed-off-by: Gwendal Grignou <gwen...@chromium.org>
---
Changes in v7:
- Split patch in two: This is the MFD section.

 drivers/mfd/cros_ec_dev.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 54a58df571b6..d992365472b8 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -297,13 +297,15 @@ static void cros_ec_sensors_register(struct cros_ec_dev 
*ec)
 
        resp = (struct ec_response_motion_sense *)msg->data;
        sensor_num = resp->dump.sensor_count;
-       /* Allocate 1 extra sensors in FIFO are needed */
-       sensor_cells = kcalloc(sensor_num + 1, sizeof(struct mfd_cell),
+       /*
+        * Allocate 2 extra sensors if lid angle sensor and/or FIFO are needed.
+        */
+       sensor_cells = kcalloc(sensor_num + 2, sizeof(struct mfd_cell),
                               GFP_KERNEL);
        if (sensor_cells == NULL)
                goto error;
 
-       sensor_platforms = kcalloc(sensor_num + 1,
+       sensor_platforms = kcalloc(sensor_num,
                                   sizeof(struct cros_ec_sensor_platform),
                                   GFP_KERNEL);
        if (sensor_platforms == NULL)
@@ -363,6 +365,11 @@ static void cros_ec_sensors_register(struct cros_ec_dev 
*ec)
                sensor_cells[id].name = "cros-ec-ring";
                id++;
        }
+       if (cros_ec_check_features(ec,
+                               EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
+               sensor_cells[id].name = "cros-ec-lid-angle";
+               id++;
+       }
 
        ret = mfd_add_devices(ec->dev, 0, sensor_cells, id,
                              NULL, 0, NULL);
-- 
2.21.0.1020.gf2820cf01a-goog