[PATCH] platform: chrome: Allocate sensorhub resource before claiming sensors

From: Gwendal Grignou
Date: Mon Apr 27 2020 - 18:59:11 EST


Allocate callbacks array before enumerating the sensors:
The probe routine for these sensors (for instance cros_ec_sensors_probe)
can be called within the sensorhub probe routine
(cros_ec_sensors_probe())

Fixes: 145d59baff594 ("platform/chrome: cros_ec_sensorhub: Add FIFO support")

Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_sensorhub.c | 80 +++++++++++--------
.../platform/chrome/cros_ec_sensorhub_ring.c | 73 ++++++++++-------
.../linux/platform_data/cros_ec_sensorhub.h | 1 +
3 files changed, 93 insertions(+), 61 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c
index b7f2c00db5e1e..9c4af76a9956e 100644
--- a/drivers/platform/chrome/cros_ec_sensorhub.c
+++ b/drivers/platform/chrome/cros_ec_sensorhub.c
@@ -52,28 +52,15 @@ static int cros_ec_sensorhub_register(struct device *dev,
int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };
struct cros_ec_command *msg = sensorhub->msg;
struct cros_ec_dev *ec = sensorhub->ec;
- int ret, i, sensor_num;
+ int ret, i;
char *name;

- sensor_num = cros_ec_get_sensor_count(ec);
- if (sensor_num < 0) {
- dev_err(dev,
- "Unable to retrieve sensor information (err:%d)\n",
- sensor_num);
- return sensor_num;
- }
-
- sensorhub->sensor_num = sensor_num;
- if (sensor_num == 0) {
- dev_err(dev, "Zero sensors reported.\n");
- return -EINVAL;
- }

msg->version = 1;
msg->insize = sizeof(struct ec_response_motion_sense);
msg->outsize = sizeof(struct ec_params_motion_sense);

- for (i = 0; i < sensor_num; i++) {
+ for (i = 0; i < sensorhub->sensor_num; i++) {
sensorhub->params->cmd = MOTIONSENSE_CMD_INFO;
sensorhub->params->info.sensor_num = i;

@@ -140,8 +127,7 @@ static int cros_ec_sensorhub_probe(struct platform_device *pdev)
struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
struct cros_ec_sensorhub *data;
struct cros_ec_command *msg;
- int ret;
- int i;
+ int ret, i, sensor_num;

msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) +
max((u16)sizeof(struct ec_params_motion_sense),
@@ -166,10 +152,52 @@ static int cros_ec_sensorhub_probe(struct platform_device *pdev)
dev_set_drvdata(dev, data);

/* Check whether this EC is a sensor hub. */
- if (cros_ec_check_features(data->ec, EC_FEATURE_MOTION_SENSE)) {
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) {
+ sensor_num = cros_ec_get_sensor_count(ec);
+ if (sensor_num < 0) {
+ dev_err(dev,
+ "Unable to retrieve sensor information (err:%d)\n",
+ sensor_num);
+ return sensor_num;
+ }
+ if (sensor_num == 0) {
+ dev_err(dev, "Zero sensors reported.\n");
+ return -EINVAL;
+ }
+ data->sensor_num = sensor_num;
+
+ /*
+ * Prepare the ring handler before enumering the
+ * sensors.
+ */
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
+ ret = cros_ec_sensorhub_ring_allocate(data);
+ if (ret)
+ return ret;
+ }
+
+ /* Enumerate the sensors.*/
ret = cros_ec_sensorhub_register(dev, data);
if (ret)
return ret;
+
+ /*
+ * When the EC does not have a FIFO, the sensors will query
+ * their data themselves via sysfs or a software trigger.
+ */
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
+ ret = cros_ec_sensorhub_ring_add(data);
+ if (ret)
+ return ret;
+ /*
+ * The msg and its data is not under the control of the
+ * ring handler.
+ */
+ return devm_add_action_or_reset(dev,
+ cros_ec_sensorhub_ring_remove,
+ data);
+ }
+
} else {
/*
* If the device has sensors but does not claim to
@@ -184,22 +212,6 @@ static int cros_ec_sensorhub_probe(struct platform_device *pdev)
}
}

- /*
- * If the EC does not have a FIFO, the sensors will query their data
- * themselves via sysfs or a software trigger.
- */
- if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
- ret = cros_ec_sensorhub_ring_add(data);
- if (ret)
- return ret;
- /*
- * The msg and its data is not under the control of the ring
- * handler.
- */
- return devm_add_action_or_reset(dev,
- cros_ec_sensorhub_ring_remove,
- data);
- }

return 0;
}
diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c
index c48e5b38a4417..24e48d96ed766 100644
--- a/drivers/platform/chrome/cros_ec_sensorhub_ring.c
+++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c
@@ -957,17 +957,15 @@ static int cros_ec_sensorhub_event(struct notifier_block *nb,
}

/**
- * cros_ec_sensorhub_ring_add() - Add the FIFO functionality if the EC
- * supports it.
+ * cros_ec_sensorhub_ring_allocate() - Prepare the FIFO functionality if the EC
+ * supports it.
*
* @sensorhub : Sensor Hub object.
*
* Return: 0 on success.
*/
-int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub)
+int cros_ec_sensorhub_ring_allocate(struct cros_ec_sensorhub *sensorhub)
{
- struct cros_ec_dev *ec = sensorhub->ec;
- int ret;
int fifo_info_length =
sizeof(struct ec_response_motion_sense_fifo_info) +
sizeof(u16) * sensorhub->sensor_num;
@@ -978,6 +976,49 @@ int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub)
if (!sensorhub->fifo_info)
return -ENOMEM;

+ /*
+ * Allocate the callback area based on the number of sensors.
+ * Add one for the sensor ring.
+ */
+ sensorhub->push_data = devm_kcalloc(sensorhub->dev,
+ sensorhub->sensor_num,
+ sizeof(*sensorhub->push_data),
+ GFP_KERNEL);
+ if (!sensorhub->push_data)
+ return -ENOMEM;
+
+ sensorhub->tight_timestamps = cros_ec_check_features(
+ sensorhub->ec,
+ EC_FEATURE_MOTION_SENSE_TIGHT_TIMESTAMPS);
+
+ if (sensorhub->tight_timestamps) {
+ sensorhub->batch_state = devm_kcalloc(sensorhub->dev,
+ sensorhub->sensor_num,
+ sizeof(*sensorhub->batch_state),
+ GFP_KERNEL);
+ if (!sensorhub->batch_state)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/**
+ * cros_ec_sensorhub_ring_add() - Add the FIFO functionality if the EC
+ * supports it.
+ *
+ * @sensorhub : Sensor Hub object.
+ *
+ * Return: 0 on success.
+ */
+int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub)
+{
+ struct cros_ec_dev *ec = sensorhub->ec;
+ int ret;
+ int fifo_info_length =
+ sizeof(struct ec_response_motion_sense_fifo_info) +
+ sizeof(u16) * sensorhub->sensor_num;
+
/* Retrieve FIFO information */
sensorhub->msg->version = 2;
sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INFO;
@@ -998,31 +1039,9 @@ int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub)
if (!sensorhub->ring)
return -ENOMEM;

- /*
- * Allocate the callback area based on the number of sensors.
- */
- sensorhub->push_data = devm_kcalloc(
- sensorhub->dev, sensorhub->sensor_num,
- sizeof(*sensorhub->push_data),
- GFP_KERNEL);
- if (!sensorhub->push_data)
- return -ENOMEM;
-
sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] =
cros_ec_get_time_ns();

- sensorhub->tight_timestamps = cros_ec_check_features(
- ec, EC_FEATURE_MOTION_SENSE_TIGHT_TIMESTAMPS);
-
- if (sensorhub->tight_timestamps) {
- sensorhub->batch_state = devm_kcalloc(sensorhub->dev,
- sensorhub->sensor_num,
- sizeof(*sensorhub->batch_state),
- GFP_KERNEL);
- if (!sensorhub->batch_state)
- return -ENOMEM;
- }
-
/* Register the notifier that will act as a top half interrupt. */
sensorhub->notifier.notifier_call = cros_ec_sensorhub_event;
ret = blocking_notifier_chain_register(&ec->ec_dev->event_notifier,
diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h
index c588be843f61b..0ecce6aa69d5e 100644
--- a/include/linux/platform_data/cros_ec_sensorhub.h
+++ b/include/linux/platform_data/cros_ec_sensorhub.h
@@ -185,6 +185,7 @@ int cros_ec_sensorhub_register_push_data(struct cros_ec_sensorhub *sensorhub,
void cros_ec_sensorhub_unregister_push_data(struct cros_ec_sensorhub *sensorhub,
u8 sensor_num);

+int cros_ec_sensorhub_ring_allocate(struct cros_ec_sensorhub *sensorhub);
int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub);
void cros_ec_sensorhub_ring_remove(void *arg);
int cros_ec_sensorhub_ring_fifo_enable(struct cros_ec_sensorhub *sensorhub,
--
2.26.2.303.gf8c07b1a785-goog