Re: [PATCH 12/13] iio: cros_ec: Report hwfifo_watermark_max

Jonathan Cameron
2019-10-05T16:37:39Z

On Sun, 22 Sep 2019 10:50:20 -0700
Gwendal Grignou <gwendal@chromium.org> wrote:

> Report the maximum amount of sample the EC can hold.
> This is not tunable, but can be useful for application to find out the
> maximum amount of time it can sleep when hwfifo_timeout is set to a
> large number.
>
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Looks good to me. I'm adding tags because I have no idea what route
this will eventually take and it saves me trying to remember which
patches need another look in v2.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
> .../cros_ec_sensors/cros_ec_sensors_core.c | 35 +++++++++++++++++--
> .../linux/iio/common/cros_ec_sensors_core.h | 4 ++-
> 2 files changed, 36 insertions(+), 3 deletions(-)
>
> 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 a31a761e3a81..a32260c9bc09 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
> @@ -23,6 +23,12 @@
> #include <linux/platform_data/cros_ec_sensorhub.h>
> #include <linux/platform_device.h>
>
> +/*
> + * Hard coded to the first device to support sensor fifo. The EC has a 2048
> + * byte fifo and will trigger an interrupt when fifo is 2/3 full.
> + */
> +#define CROS_EC_FIFO_SIZE (2048 * 2 / 3)
> +
> static char *cros_ec_loc[] = {
> [MOTIONSENSE_LOC_BASE] = "base",
> [MOTIONSENSE_LOC_LID] = "lid",
> @@ -56,8 +62,15 @@ static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev,
>
> static void get_default_min_max_freq(enum motionsensor_type type,
> u32 *min_freq,
> - u32 *max_freq)
> + u32 *max_freq,
> + u32 *max_fifo_events)
> {
> + /*
> + * We don't know fifo size, set to size previously used by older
> + * hardware.
> + */
> + *max_fifo_events = CROS_EC_FIFO_SIZE;
> +
> switch (type) {
> case MOTIONSENSE_TYPE_ACCEL:
> case MOTIONSENSE_TYPE_GYRO:
> @@ -122,6 +135,7 @@ static ssize_t cros_ec_sensor_set_report_latency(struct device *dev,
> return len;
> }
>
> +
> static ssize_t cros_ec_sensor_get_report_latency(struct device *dev,
> struct device_attribute *attr,
> char *buf)
> @@ -149,8 +163,22 @@ static IIO_DEVICE_ATTR(hwfifo_timeout, 0644,
> cros_ec_sensor_get_report_latency,
> cros_ec_sensor_set_report_latency, 0);
>
> +static ssize_t hwfifo_watermark_max_show(
> + struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> + struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
> +
> + return sprintf(buf, "%d\n", st->fifo_max_event_count);
> +}
> +
> +static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0);
> +
> static const struct attribute *cros_ec_sensor_fifo_attributes[] = {
> &iio_dev_attr_hwfifo_timeout.dev_attr.attr,
> + &iio_dev_attr_hwfifo_watermark_max.dev_attr.attr,
> NULL,
> };
>
> @@ -251,12 +279,15 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
> if (state->msg->version < 3) {
> get_default_min_max_freq(state->resp->info.type,
> &state->frequencies[1],
> - &state->frequencies[2]);
> + &state->frequencies[2],
> + &state->fifo_max_event_count);
> } else {
> state->frequencies[1] =
> state->resp->info_3.min_frequency;
> state->frequencies[2] =
> state->resp->info_3.max_frequency;
> + state->fifo_max_event_count =
> + state->resp->info_3.fifo_max_event_count;
> }
>
> if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
> diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
> index 60f78f0e4884..2c6acbde0d02 100644
> --- a/include/linux/iio/common/cros_ec_sensors_core.h
> +++ b/include/linux/iio/common/cros_ec_sensors_core.h
> @@ -54,7 +54,8 @@ typedef irqreturn_t (*cros_ec_sensors_capture_t)(int irq, void *p);
> * the timestamp. The timestamp is always last and
> * is always 8-byte aligned.
> * @read_ec_sensors_data: function used for accessing sensors values
> - * @cuur_sampl_freq: current sampling period
> + * @curr_sampl_freq: current sampling period
> + * @fifo_max_event_count: Size of the EC sensor FIFO
> */
> struct cros_ec_sensors_core_state {
> struct cros_ec_device *ec;
> @@ -78,6 +79,7 @@ struct cros_ec_sensors_core_state {
> unsigned long scan_mask, s16 *data);
>
> int curr_sampl_freq;
> + u32 fifo_max_event_count;
>
> /* Table of known available frequencies : 0, Min and Max in mHz */
> int frequencies[3];