[PATCH v4 13/17] iio: cros_ec: Register to cros_ec_sensorhub when EC supports FIFO

Gwendal Grignou
2019-11-05T22:27:47Z

When EC supports FIFO, each IIO device registers a callback, to put
samples in the buffer when they arrives from the FIFO.
We can still use a trigger to collect samples, but there may be some
duplications in the buffer: EC has a single FIFO, so once one sensor is
using it, all sensors event will be in the FIFO.
To be sure events generated by cros_ec_sensorhub or the trigger uses the
same time domain, current_timestamp_clock must be set to "boottime".

When no FIFO, the user space app needs to call trigger_new, or better
register a high precision timer.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
Changes in v4:
- Fix a logic error when the sensor is not "physical", for instance lig
angle: core_init() would return !0 even if there was no error.
- Check patch with --strict option
Use sizeof(*obj) instead of sizeof(struct ...obj)
Alignement
Change in v3:
- Remove double line
- Fix indentation
- Add code to support iio clock_id setting. Optimized for
CLOCK_BOOTTIME.
Change in v2 from "Use triggered buffer only when EC does not support
FIFO":
- Keep trigger all the time.
- Add devm_add_action to cleanup callback registration.
- EC that "reports" legacy sensors do not have FIFO.
- Use iiio_is_buffer_enabled instead of checking the scan_mask
before sending samples to buffer.
- Add empty lines for visibility.

drivers/iio/accel/cros_ec_accel_legacy.c | 8 +-
.../cros_ec_sensors/cros_ec_lid_angle.c | 2 +-
.../common/cros_ec_sensors/cros_ec_sensors.c | 9 +-
.../cros_ec_sensors/cros_ec_sensors_core.c | 85 ++++++++++++++++++-
drivers/iio/light/cros_ec_light_prox.c | 9 +-
drivers/iio/pressure/cros_ec_baro.c | 9 +-
.../linux/iio/common/cros_ec_sensors_core.h | 10 ++-
7 files changed, 103 insertions(+), 29 deletions(-)

diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index 65f85faf6f31..b9f651e4ce99 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -171,7 +171,8 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
if (!indio_dev)
return -ENOMEM;

- ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
+ cros_ec_sensors_capture, NULL);
if (ret)
return ret;

@@ -191,11 +192,6 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
state->sign[CROS_EC_SENSOR_Z] = -1;
}

- ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
- cros_ec_sensors_capture, NULL);
- if (ret)
- return ret;
-
return devm_iio_device_register(dev, indio_dev);
}

diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c b/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c
index 1dcc2a16ab2d..e30a59fcf0f9 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c
@@ -97,7 +97,7 @@ static int cros_ec_lid_angle_probe(struct platform_device *pdev)
if (!indio_dev)
return -ENOMEM;

- ret = cros_ec_sensors_core_init(pdev, indio_dev, false);
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, false, NULL, NULL);
if (ret)
return ret;

diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
index 7dce04473467..62a0dd970988 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -231,7 +231,9 @@ static int cros_ec_sensors_probe(struct platform_device *pdev)
if (!indio_dev)
return -ENOMEM;

- ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
+ cros_ec_sensors_capture,
+ cros_ec_sensors_push_data);
if (ret)
return ret;

@@ -293,11 +295,6 @@ static int cros_ec_sensors_probe(struct platform_device *pdev)
else
state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;

- ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
- cros_ec_sensors_capture, NULL);
- if (ret)
- return ret;
-
return devm_iio_device_register(dev, indio_dev);
}

diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
index b47da497a3c3..904cd26dd31f 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
@@ -12,6 +12,7 @@
#include <linux/iio/iio.h>
#include <linux/iio/kfifo_buf.h>
#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#include <linux/kernel.h>
#include <linux/mfd/cros_ec.h>
#include <linux/module.h>
@@ -83,17 +84,78 @@ static void get_default_min_max_freq(enum motionsensor_type type,
}
}

+int cros_ec_sensors_push_data(struct iio_dev *indio_dev,
+ s16 *data,
+ s64 timestamp)
+{
+ struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+ s16 *out;
+ s64 delta;
+ unsigned int i;
+
+ /*
+ * It can happen if we get a samples before the iio device is fully
+ * registered.
+ */
+ if (!st)
+ return 0;
+
+ /*
+ * Ignore samples if the buffer is not set: it is needed if the ODR is
+ * set but the buffer is not enabled yet.
+ */
+ if (!iio_buffer_enabled(indio_dev))
+ return 0;
+
+ out = (s16 *)st->samples;
+ for_each_set_bit(i,
+ indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ *out = data[i];
+ out++;
+ }
+
+ if (iio_device_get_clock(indio_dev) != CLOCK_BOOTTIME)
+ delta = iio_get_time_ns(indio_dev) - cros_ec_get_time_ns();
+ else
+ delta = 0;
+
+ iio_push_to_buffers_with_timestamp(indio_dev, st->samples,
+ timestamp + delta);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cros_ec_sensors_push_data);
+
+static void cros_ec_sensors_core_clean(void *arg)
+{
+ struct platform_device *pdev = (struct platform_device *)arg;
+ struct cros_ec_sensorhub *sensor_hub =
+ dev_get_drvdata(pdev->dev.parent);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+ u8 sensor_num = st->param.info.sensor_num;
+
+ cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num);
+}
+
/**
* cros_ec_sensors_core_init() - basic initialization of the core structure
* @pdev: platform device created for the sensors
* @indio_dev: iio device structure of the device
* @physical_device: true if the device refers to a physical device
+ * @trigger_capture: function pointer to call buffer is triggered,
+ * for backward compatibility.
+ * @push_data: function to call when cros_ec_sensorhub receives
+ * a sample for that sensor.
*
* Return: 0 on success, -errno on failure.
*/
int cros_ec_sensors_core_init(struct platform_device *pdev,
struct iio_dev *indio_dev,
- bool physical_device)
+ bool physical_device,
+ cros_ec_sensors_capture_t trigger_capture,
+ cros_ec_sensorhub_push_data_cb_t push_data)
{
struct device *dev = &pdev->dev;
struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
@@ -132,8 +194,6 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
indio_dev->name = pdev->name;

if (physical_device) {
- indio_dev->modes = INDIO_DIRECT_MODE;
-
state->param.cmd = MOTIONSENSE_CMD_INFO;
state->param.info.sensor_num = sensor_platform->sensor_num;
ret = cros_ec_motion_send_host_cmd(state, 0);
@@ -162,6 +222,25 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
state->frequencies[2] =
state->resp->info_3.max_frequency;
}
+
+ ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+ trigger_capture, NULL);
+ if (ret)
+ return ret;
+
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
+ ret = cros_ec_sensorhub_register_push_data(sensor_hub,
+ sensor_platform->sensor_num,
+ indio_dev, push_data);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(dev,
+ cros_ec_sensors_core_clean,
+ pdev);
+ if (ret)
+ return ret;
+ }
}

return 0;
diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
index d85a391e50c5..698b2ee81ebf 100644
--- a/drivers/iio/light/cros_ec_light_prox.c
+++ b/drivers/iio/light/cros_ec_light_prox.c
@@ -178,7 +178,9 @@ static int cros_ec_light_prox_probe(struct platform_device *pdev)
if (!indio_dev)
return -ENOMEM;

- ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
+ cros_ec_sensors_capture,
+ cros_ec_sensors_push_data);
if (ret)
return ret;

@@ -237,11 +239,6 @@ static int cros_ec_light_prox_probe(struct platform_device *pdev)

state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;

- ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
- cros_ec_sensors_capture, NULL);
- if (ret)
- return ret;
-
return devm_iio_device_register(dev, indio_dev);
}

diff --git a/drivers/iio/pressure/cros_ec_baro.c b/drivers/iio/pressure/cros_ec_baro.c
index 2354302375de..e1c86b22676c 100644
--- a/drivers/iio/pressure/cros_ec_baro.c
+++ b/drivers/iio/pressure/cros_ec_baro.c
@@ -134,7 +134,9 @@ static int cros_ec_baro_probe(struct platform_device *pdev)
if (!indio_dev)
return -ENOMEM;

- ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
+ cros_ec_sensors_capture,
+ cros_ec_sensors_push_data);
if (ret)
return ret;

@@ -180,11 +182,6 @@ static int cros_ec_baro_probe(struct platform_device *pdev)

state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;

- ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
- cros_ec_sensors_capture, NULL);
- if (ret)
- return ret;
-
return devm_iio_device_register(dev, indio_dev);
}

diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
index 0af918978f97..b8f573ca9dcc 100644
--- a/include/linux/iio/common/cros_ec_sensors_core.h
+++ b/include/linux/iio/common/cros_ec_sensors_core.h
@@ -12,6 +12,7 @@
#include <linux/irqreturn.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_data/cros_ec_sensorhub.h>

enum {
CROS_EC_SENSOR_X,
@@ -32,6 +33,8 @@ enum {
/* Minimum sampling period to use when device is suspending */
#define CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY 1000 /* 1 second */

+typedef irqreturn_t (*cros_ec_sensors_capture_t)(int irq, void *p);
+
/**
* struct cros_ec_sensors_core_state - state data for EC sensors IIO driver
* @ec: cros EC device structure
@@ -87,9 +90,14 @@ int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev, unsigned long scan_mask,

struct platform_device;
int cros_ec_sensors_core_init(struct platform_device *pdev,
- struct iio_dev *indio_dev, bool physical_device);
+ struct iio_dev *indio_dev, bool physical_device,
+ cros_ec_sensors_capture_t trigger_capture,
+ cros_ec_sensorhub_push_data_cb_t push_data);

irqreturn_t cros_ec_sensors_capture(int irq, void *p);
+int cros_ec_sensors_push_data(struct iio_dev *indio_dev,
+ s16 *data,
+ s64 timestamp);

int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *st,
u16 opt_length);
--
2.24.0.rc1.363.gb1bccd3e3d-goog