[PATCH v6 0/4] Support accelerometers for veyron_minnie

[PATCH v6 0/4] Support accelerometers for veyron_minnie

[Gwendal Grignou]

veyron_minnie - ASUS Chromebook Flip C100PA - embedded controller
controls two accelerometers, one in the lid, one in the base.
However, the EC firmware does not follow the new interface that
cros_ec_accel driver use.
Extend the legacy driver used on glimmer - Lenovo ThinkPad 11e
Chromebook - to veyron_minnie.
veyron_minnie being ARM based, issue command over the I2C bus to the EC
instead of relying on the shared registers over LPC.

Gwendal Grignou (4):
  iio: cros_ec: Add sign vector in core for backward compatibility
  iio: cros_ec_accel_legacy: Fix incorrect channel setting
  iio: cros_ec_accel_legacy: Use cros_ec_sensors_core
  iio: cros_ec_accel_legacy: Add support for veyron-minnie

Changes in v5:
- In "Use cros_ec_sensors_core", fix return without unlock on the error
  path properly.

Changes in v5:
- In "Use cros_ec_sensors_core", fix return without unlock on the error
  path.
- Add acked for the last 2 patches.

Changes in v4:
- No change in iio/common/cros_ec_sensors
- Split cros_ec_accel_legacy code in 3:
  - fix an error in channel setting.
  - remove duplicate code in cros_ec_accel, use cros_ec_sensors_core.
  - extend cros_ec_accel to ARM device.
- Define cros_ec_accel_legacy_read_cmd() as static.

Changes in v3:
- Fix commit message, add reviewed-by for first patch.

Changes in v2:
- Readd empty line to reduce amount of change in patch.
- Remove Keywords used by ChromeOS commit queue.


 drivers/iio/accel/Kconfig                     |   4 +-
 drivers/iio/accel/cros_ec_accel_legacy.c      | 353 ++++--------------
 .../cros_ec_sensors/cros_ec_sensors_core.c    |   4 +
 .../linux/iio/common/cros_ec_sensors_core.h   |   1 +
 4 files changed, 86 insertions(+), 276 deletions(-)

-- 
2.22.0.510.g264f2c817a-goog

[PATCH v6 1/4] iio: cros_ec: Add sign vector in core for backward compatibility

[Gwendal Grignou]

To allow cros_ec iio core library to be used with legacy device, add a
vector to rotate sensor data if necessary: legacy devices are not
reporting data in HTML5/Android sensor referential.

Check the data is not rotated on recent chromebooks that use the HTML5
standard to present sensor data.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
---
 drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c | 4 ++++
 include/linux/iio/common/cros_ec_sensors_core.h           | 1 +
 2 files changed, 5 insertions(+)

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 719a0df5aeeb..e8a4d78659c8 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
@@ -66,6 +66,9 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
 		}
 		state->type = state->resp->info.type;
 		state->loc = state->resp->info.location;
+
+		/* Set sign vector, only used for backward compatibility. */
+		memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS);
 	}
 
 	return 0;
@@ -254,6 +257,7 @@ static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev,
 		if (ret < 0)
 			return ret;
 
+		*data *= st->sign[i];
 		data++;
 	}
 
diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
index ce16445411ac..a1c85ad4df91 100644
--- a/include/linux/iio/common/cros_ec_sensors_core.h
+++ b/include/linux/iio/common/cros_ec_sensors_core.h
@@ -71,6 +71,7 @@ struct cros_ec_sensors_core_state {
 	enum motionsensor_location loc;
 
 	s16 calib[CROS_EC_SENSOR_MAX_AXIS];
+	s8 sign[CROS_EC_SENSOR_MAX_AXIS];
 
 	u8 samples[CROS_EC_SAMPLE_SIZE];
 
-- 
2.22.0.510.g264f2c817a-goog

Re: [PATCH v6 1/4] iio: cros_ec: Add sign vector in core for backward compatibility

[Jonathan Cameron]

On Mon, 15 Jul 2019 16:14:51 -0700
Gwendal Grignou <gwendal@chromium.org> wrote:

> To allow cros_ec iio core library to be used with legacy device, add a
> vector to rotate sensor data if necessary: legacy devices are not
> reporting data in HTML5/Android sensor referential.
> 
> Check the data is not rotated on recent chromebooks that use the HTML5
> standard to present sensor data.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c | 4 ++++
>  include/linux/iio/common/cros_ec_sensors_core.h           | 1 +
>  2 files changed, 5 insertions(+)
> 
> 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 719a0df5aeeb..e8a4d78659c8 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
> @@ -66,6 +66,9 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
>  		}
>  		state->type = state->resp->info.type;
>  		state->loc = state->resp->info.location;
> +
> +		/* Set sign vector, only used for backward compatibility. */
> +		memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS);
>  	}
>  
>  	return 0;
> @@ -254,6 +257,7 @@ static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev,
>  		if (ret < 0)
>  			return ret;
>  
> +		*data *= st->sign[i];
>  		data++;
>  	}
>  
> diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
> index ce16445411ac..a1c85ad4df91 100644
> --- a/include/linux/iio/common/cros_ec_sensors_core.h
> +++ b/include/linux/iio/common/cros_ec_sensors_core.h
> @@ -71,6 +71,7 @@ struct cros_ec_sensors_core_state {
>  	enum motionsensor_location loc;
>  
>  	s16 calib[CROS_EC_SENSOR_MAX_AXIS];
> +	s8 sign[CROS_EC_SENSOR_MAX_AXIS];
>  
>  	u8 samples[CROS_EC_SAMPLE_SIZE];
>  

[PATCH v6 2/4] iio: cros_ec_accel_legacy: Fix incorrect channel setting

[Gwendal Grignou]

INFO_SCALE is set both for each channel and all channels.
iio is using all channel setting, so the error was not user visible.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
 drivers/iio/accel/cros_ec_accel_legacy.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index 46bb2e421bb9..ad19d9c716f4 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -319,7 +319,6 @@ static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
 		.modified = 1,					        \
 		.info_mask_separate =					\
 			BIT(IIO_CHAN_INFO_RAW) |			\
-			BIT(IIO_CHAN_INFO_SCALE) |			\
 			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
 		.ext_info = cros_ec_accel_legacy_ext_info,		\
-- 
2.22.0.510.g264f2c817a-goog

Re: [PATCH v6 2/4] iio: cros_ec_accel_legacy: Fix incorrect channel setting

[Jonathan Cameron]

On Mon, 15 Jul 2019 16:14:52 -0700
Gwendal Grignou <gwendal@chromium.org> wrote:

> INFO_SCALE is set both for each channel and all channels.
> iio is using all channel setting, so the error was not user visible.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/accel/cros_ec_accel_legacy.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
> index 46bb2e421bb9..ad19d9c716f4 100644
> --- a/drivers/iio/accel/cros_ec_accel_legacy.c
> +++ b/drivers/iio/accel/cros_ec_accel_legacy.c
> @@ -319,7 +319,6 @@ static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
>  		.modified = 1,					        \
>  		.info_mask_separate =					\
>  			BIT(IIO_CHAN_INFO_RAW) |			\
> -			BIT(IIO_CHAN_INFO_SCALE) |			\
>  			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
>  		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
>  		.ext_info = cros_ec_accel_legacy_ext_info,		\

[PATCH v6 3/4] iio: cros_ec_accel_legacy: Use cros_ec_sensors_core

[Gwendal Grignou]

Remove duplicate code in cros-ec-accel-legacy,
use cros-ec-sensors-core functions and structures when possible.

On glimmer, check the 2 accelerometers are presented and working.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/accel/Kconfig                |   4 +-
 drivers/iio/accel/cros_ec_accel_legacy.c | 336 ++++-------------------
 2 files changed, 55 insertions(+), 285 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 62a970a20219..7d0848f9ea45 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -201,9 +201,7 @@ config HID_SENSOR_ACCEL_3D
 
 config IIO_CROS_EC_ACCEL_LEGACY
 	tristate "ChromeOS EC Legacy Accelerometer Sensor"
-	select IIO_BUFFER
-	select IIO_TRIGGERED_BUFFER
-	select CROS_EC_LPC_REGISTER_DEVICE
+	depends on IIO_CROS_EC_SENSORS_CORE
 	help
 	  Say yes here to get support for accelerometers on Chromebook using
 	  legacy EC firmware.
diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index ad19d9c716f4..f65578c65a1c 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -12,6 +12,7 @@
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/iio/buffer.h>
+#include <linux/iio/common/cros_ec_sensors_core.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/kfifo_buf.h>
 #include <linux/iio/trigger_consumer.h>
@@ -25,191 +26,51 @@
 
 #define DRV_NAME	"cros-ec-accel-legacy"
 
+#define CROS_EC_SENSOR_LEGACY_NUM 2
 /*
  * Sensor scale hard coded at 10 bits per g, computed as:
  * g / (2^10 - 1) = 0.009586168; with g = 9.80665 m.s^-2
  */
 #define ACCEL_LEGACY_NSCALE 9586168
 
-/* Indices for EC sensor values. */
-enum {
-	X,
-	Y,
-	Z,
-	MAX_AXIS,
-};
-
-/* State data for cros_ec_accel_legacy iio driver. */
-struct cros_ec_accel_legacy_state {
-	struct cros_ec_device *ec;
-
-	/*
-	 * Array holding data from a single capture. 2 bytes per channel
-	 * for the 3 channels plus the timestamp which is always last and
-	 * 8-bytes aligned.
-	 */
-	s16 capture_data[8];
-	s8 sign[MAX_AXIS];
-	u8 sensor_num;
-};
-
-static int ec_cmd_read_u8(struct cros_ec_device *ec, unsigned int offset,
-			  u8 *dest)
-{
-	return ec->cmd_readmem(ec, offset, 1, dest);
-}
-
-static int ec_cmd_read_u16(struct cros_ec_device *ec, unsigned int offset,
-			   u16 *dest)
-{
-	__le16 tmp;
-	int ret = ec->cmd_readmem(ec, offset, 2, &tmp);
-
-	*dest = le16_to_cpu(tmp);
-
-	return ret;
-}
-
-/**
- * read_ec_until_not_busy() - Read from EC status byte until it reads not busy.
- * @st: Pointer to state information for device.
- *
- * This function reads EC status until its busy bit gets cleared. It does not
- * wait indefinitely and returns -EIO if the EC status is still busy after a
- * few hundreds milliseconds.
- *
- * Return: 8-bit status if ok, -EIO on error
- */
-static int read_ec_until_not_busy(struct cros_ec_accel_legacy_state *st)
-{
-	struct cros_ec_device *ec = st->ec;
-	u8 status;
-	int attempts = 0;
-
-	ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
-	while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) {
-		/* Give up after enough attempts, return error. */
-		if (attempts++ >= 50)
-			return -EIO;
-
-		/* Small delay every so often. */
-		if (attempts % 5 == 0)
-			msleep(25);
-
-		ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
-	}
-
-	return status;
-}
-
-/**
- * read_ec_accel_data_unsafe() - Read acceleration data from EC shared memory.
- * @st:        Pointer to state information for device.
- * @scan_mask: Bitmap of the sensor indices to scan.
- * @data:      Location to store data.
- *
- * This is the unsafe function for reading the EC data. It does not guarantee
- * that the EC will not modify the data as it is being read in.
- */
-static void read_ec_accel_data_unsafe(struct cros_ec_accel_legacy_state *st,
-				      unsigned long scan_mask, s16 *data)
-{
-	int i = 0;
-	int num_enabled = bitmap_weight(&scan_mask, MAX_AXIS);
-
-	/* Read all sensors enabled in scan_mask. Each value is 2 bytes. */
-	while (num_enabled--) {
-		i = find_next_bit(&scan_mask, MAX_AXIS, i);
-		ec_cmd_read_u16(st->ec,
-				EC_MEMMAP_ACC_DATA +
-				sizeof(s16) *
-				(1 + i + st->sensor_num * MAX_AXIS),
-				data);
-		*data *= st->sign[i];
-		i++;
-		data++;
-	}
-}
-
-/**
- * read_ec_accel_data() - Read acceleration data from EC shared memory.
- * @st:        Pointer to state information for device.
- * @scan_mask: Bitmap of the sensor indices to scan.
- * @data:      Location to store data.
- *
- * This is the safe function for reading the EC data. It guarantees that
- * the data sampled was not modified by the EC while being read.
- *
- * Return: 0 if ok, -ve on error
- */
-static int read_ec_accel_data(struct cros_ec_accel_legacy_state *st,
-			      unsigned long scan_mask, s16 *data)
-{
-	u8 samp_id = 0xff;
-	u8 status = 0;
-	int ret;
-	int attempts = 0;
-
-	/*
-	 * Continually read all data from EC until the status byte after
-	 * all reads reflects that the EC is not busy and the sample id
-	 * matches the sample id from before all reads. This guarantees
-	 * that data read in was not modified by the EC while reading.
-	 */
-	while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT |
-			  EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) {
-		/* If we have tried to read too many times, return error. */
-		if (attempts++ >= 5)
-			return -EIO;
-
-		/* Read status byte until EC is not busy. */
-		ret = read_ec_until_not_busy(st);
-		if (ret < 0)
-			return ret;
-		status = ret;
-
-		/*
-		 * Store the current sample id so that we can compare to the
-		 * sample id after reading the data.
-		 */
-		samp_id = status & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK;
-
-		/* Read all EC data, format it, and store it into data. */
-		read_ec_accel_data_unsafe(st, scan_mask, data);
-
-		/* Read status byte. */
-		ec_cmd_read_u8(st->ec, EC_MEMMAP_ACC_STATUS, &status);
-	}
-
-	return 0;
-}
-
 static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
 				     struct iio_chan_spec const *chan,
 				     int *val, int *val2, long mask)
 {
-	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
+	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
 	s16 data = 0;
-	int ret = IIO_VAL_INT;
+	int ret;
+	int idx = chan->scan_index;
+
+	mutex_lock(&st->cmd_lock);
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		ret = read_ec_accel_data(st, (1 << chan->scan_index), &data);
-		if (ret)
-			return ret;
+		ret = st->read_ec_sensors_data(indio_dev, 1 << idx, &data);
+		if (ret < 0)
+			break;
+		ret = IIO_VAL_INT;
 		*val = data;
-		return IIO_VAL_INT;
+		break;
 	case IIO_CHAN_INFO_SCALE:
+		WARN_ON(st->type != MOTIONSENSE_TYPE_ACCEL);
 		*val = 0;
 		*val2 = ACCEL_LEGACY_NSCALE;
-		return IIO_VAL_INT_PLUS_NANO;
+		ret = IIO_VAL_INT_PLUS_NANO;
+		break;
 	case IIO_CHAN_INFO_CALIBBIAS:
 		/* Calibration not supported. */
 		*val = 0;
-		return IIO_VAL_INT;
+		ret = IIO_VAL_INT;
+		break;
 	default:
-		return -EINVAL;
+		ret = cros_ec_sensors_core_read(st, chan, val, val2,
+				mask);
+		break;
 	}
+	mutex_unlock(&st->cmd_lock);
+
+	return ret;
 }
 
 static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
@@ -231,86 +92,14 @@ static const struct iio_info cros_ec_accel_legacy_info = {
 	.write_raw = &cros_ec_accel_legacy_write,
 };
 
-/**
- * cros_ec_accel_legacy_capture() - The trigger handler function
- * @irq: The interrupt number.
- * @p:   Private data - always a pointer to the poll func.
- *
- * On a trigger event occurring, if the pollfunc is attached then this
- * handler is called as a threaded interrupt (and hence may sleep). It
- * is responsible for grabbing data from the device and pushing it into
- * the associated buffer.
- *
- * Return: IRQ_HANDLED
+/*
+ * Present the channel using HTML5 standard:
+ * need to invert X and Y and invert some lid axis.
  */
-static irqreturn_t cros_ec_accel_legacy_capture(int irq, void *p)
-{
-	struct iio_poll_func *pf = p;
-	struct iio_dev *indio_dev = pf->indio_dev;
-	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
-
-	/* Clear capture data. */
-	memset(st->capture_data, 0, sizeof(st->capture_data));
-
-	/*
-	 * Read data based on which channels are enabled in scan mask. Note
-	 * that on a capture we are always reading the calibrated data.
-	 */
-	read_ec_accel_data(st, *indio_dev->active_scan_mask, st->capture_data);
-
-	iio_push_to_buffers_with_timestamp(indio_dev, (void *)st->capture_data,
-					   iio_get_time_ns(indio_dev));
-
-	/*
-	 * Tell the core we are done with this trigger and ready for the
-	 * next one.
-	 */
-	iio_trigger_notify_done(indio_dev->trig);
-
-	return IRQ_HANDLED;
-}
-
-static char *cros_ec_accel_legacy_loc_strings[] = {
-	[MOTIONSENSE_LOC_BASE] = "base",
-	[MOTIONSENSE_LOC_LID] = "lid",
-	[MOTIONSENSE_LOC_MAX] = "unknown",
-};
-
-static ssize_t cros_ec_accel_legacy_loc(struct iio_dev *indio_dev,
-					uintptr_t private,
-					const struct iio_chan_spec *chan,
-					char *buf)
-{
-	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
-
-	return sprintf(buf, "%s\n",
-		       cros_ec_accel_legacy_loc_strings[st->sensor_num +
-							MOTIONSENSE_LOC_BASE]);
-}
-
-static ssize_t cros_ec_accel_legacy_id(struct iio_dev *indio_dev,
-				       uintptr_t private,
-				       const struct iio_chan_spec *chan,
-				       char *buf)
-{
-	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
-
-	return sprintf(buf, "%d\n", st->sensor_num);
-}
-
-static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
-	{
-		.name = "id",
-		.shared = IIO_SHARED_BY_ALL,
-		.read = cros_ec_accel_legacy_id,
-	},
-	{
-		.name = "location",
-		.shared = IIO_SHARED_BY_ALL,
-		.read = cros_ec_accel_legacy_loc,
-	},
-	{ }
-};
+#define CROS_EC_ACCEL_ROTATE_AXIS(_axis)				\
+	((_axis) == CROS_EC_SENSOR_Z ? CROS_EC_SENSOR_Z :		\
+	 ((_axis) == CROS_EC_SENSOR_X ? CROS_EC_SENSOR_Y :		\
+	  CROS_EC_SENSOR_X))
 
 #define CROS_EC_ACCEL_LEGACY_CHAN(_axis)				\
 	{								\
@@ -321,28 +110,28 @@ static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
 			BIT(IIO_CHAN_INFO_RAW) |			\
 			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
-		.ext_info = cros_ec_accel_legacy_ext_info,		\
+		.ext_info = cros_ec_sensors_ext_info,			\
 		.scan_type = {						\
 			.sign = 's',					\
-			.realbits = 16,					\
-			.storagebits = 16,				\
+			.realbits = CROS_EC_SENSOR_BITS,		\
+			.storagebits = CROS_EC_SENSOR_BITS,		\
 		},							\
+		.scan_index = CROS_EC_ACCEL_ROTATE_AXIS(_axis),		\
 	}								\
 
-static struct iio_chan_spec ec_accel_channels[] = {
-	CROS_EC_ACCEL_LEGACY_CHAN(X),
-	CROS_EC_ACCEL_LEGACY_CHAN(Y),
-	CROS_EC_ACCEL_LEGACY_CHAN(Z),
-	IIO_CHAN_SOFT_TIMESTAMP(MAX_AXIS)
+static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = {
+		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_X),
+		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Y),
+		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Z),
+		IIO_CHAN_SOFT_TIMESTAMP(CROS_EC_SENSOR_MAX_AXIS)
 };
 
 static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
-	struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
 	struct iio_dev *indio_dev;
-	struct cros_ec_accel_legacy_state *state;
+	struct cros_ec_sensors_core_state *state;
 	int ret;
 
 	if (!ec || !ec->ec_dev) {
@@ -350,46 +139,29 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	if (!ec->ec_dev->cmd_readmem) {
-		dev_warn(&pdev->dev, "EC does not support direct reads.\n");
-		return -EINVAL;
-	}
-
 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
 	if (!indio_dev)
 		return -ENOMEM;
 
-	platform_set_drvdata(pdev, indio_dev);
-	state = iio_priv(indio_dev);
-	state->ec = ec->ec_dev;
-	state->sensor_num = sensor_platform->sensor_num;
-
-	indio_dev->dev.parent = dev;
-	indio_dev->name = pdev->name;
-	indio_dev->channels = ec_accel_channels;
-	/*
-	 * Present the channel using HTML5 standard:
-	 * need to invert X and Y and invert some lid axis.
-	 */
-	ec_accel_channels[X].scan_index = Y;
-	ec_accel_channels[Y].scan_index = X;
-	ec_accel_channels[Z].scan_index = Z;
+	ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+	if (ret)
+		return ret;
 
-	state->sign[Y] = 1;
+	indio_dev->info = &cros_ec_accel_legacy_info;
+	state = iio_priv(indio_dev);
 
-	if (state->sensor_num == MOTIONSENSE_LOC_LID)
-		state->sign[X] = state->sign[Z] = -1;
-	else
-		state->sign[X] = state->sign[Z] = 1;
+	state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
 
-	indio_dev->num_channels = ARRAY_SIZE(ec_accel_channels);
-	indio_dev->dev.parent = &pdev->dev;
-	indio_dev->info = &cros_ec_accel_legacy_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = cros_ec_accel_legacy_channels;
+	indio_dev->num_channels = ARRAY_SIZE(cros_ec_accel_legacy_channels);
+	/* The lid sensor needs to be presented inverted. */
+	if (state->loc == MOTIONSENSE_LOC_LID) {
+		state->sign[CROS_EC_SENSOR_X] = -1;
+		state->sign[CROS_EC_SENSOR_Z] = -1;
+	}
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
-					      cros_ec_accel_legacy_capture,
-					      NULL);
+			cros_ec_sensors_capture, NULL);
 	if (ret)
 		return ret;
 
-- 
2.22.0.510.g264f2c817a-goog

Re: [PATCH v6 3/4] iio: cros_ec_accel_legacy: Use cros_ec_sensors_core

[Enric Balletbo i Serra]

On 16/7/19 1:14, Gwendal Grignou wrote:
> Remove duplicate code in cros-ec-accel-legacy,
> use cros-ec-sensors-core functions and structures when possible.
> 
> On glimmer, check the 2 accelerometers are presented and working.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

As the mutex problem is fixed:

Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

> ---
>  drivers/iio/accel/Kconfig                |   4 +-
>  drivers/iio/accel/cros_ec_accel_legacy.c | 336 ++++-------------------
>  2 files changed, 55 insertions(+), 285 deletions(-)
> 
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 62a970a20219..7d0848f9ea45 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -201,9 +201,7 @@ config HID_SENSOR_ACCEL_3D
>  
>  config IIO_CROS_EC_ACCEL_LEGACY
>  	tristate "ChromeOS EC Legacy Accelerometer Sensor"
> -	select IIO_BUFFER
> -	select IIO_TRIGGERED_BUFFER
> -	select CROS_EC_LPC_REGISTER_DEVICE
> +	depends on IIO_CROS_EC_SENSORS_CORE
>  	help
>  	  Say yes here to get support for accelerometers on Chromebook using
>  	  legacy EC firmware.
> diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
> index ad19d9c716f4..f65578c65a1c 100644
> --- a/drivers/iio/accel/cros_ec_accel_legacy.c
> +++ b/drivers/iio/accel/cros_ec_accel_legacy.c
> @@ -12,6 +12,7 @@
>  #include <linux/delay.h>
>  #include <linux/device.h>
>  #include <linux/iio/buffer.h>
> +#include <linux/iio/common/cros_ec_sensors_core.h>
>  #include <linux/iio/iio.h>
>  #include <linux/iio/kfifo_buf.h>
>  #include <linux/iio/trigger_consumer.h>
> @@ -25,191 +26,51 @@
>  
>  #define DRV_NAME	"cros-ec-accel-legacy"
>  
> +#define CROS_EC_SENSOR_LEGACY_NUM 2
>  /*
>   * Sensor scale hard coded at 10 bits per g, computed as:
>   * g / (2^10 - 1) = 0.009586168; with g = 9.80665 m.s^-2
>   */
>  #define ACCEL_LEGACY_NSCALE 9586168
>  
> -/* Indices for EC sensor values. */
> -enum {
> -	X,
> -	Y,
> -	Z,
> -	MAX_AXIS,
> -};
> -
> -/* State data for cros_ec_accel_legacy iio driver. */
> -struct cros_ec_accel_legacy_state {
> -	struct cros_ec_device *ec;
> -
> -	/*
> -	 * Array holding data from a single capture. 2 bytes per channel
> -	 * for the 3 channels plus the timestamp which is always last and
> -	 * 8-bytes aligned.
> -	 */
> -	s16 capture_data[8];
> -	s8 sign[MAX_AXIS];
> -	u8 sensor_num;
> -};
> -
> -static int ec_cmd_read_u8(struct cros_ec_device *ec, unsigned int offset,
> -			  u8 *dest)
> -{
> -	return ec->cmd_readmem(ec, offset, 1, dest);
> -}
> -
> -static int ec_cmd_read_u16(struct cros_ec_device *ec, unsigned int offset,
> -			   u16 *dest)
> -{
> -	__le16 tmp;
> -	int ret = ec->cmd_readmem(ec, offset, 2, &tmp);
> -
> -	*dest = le16_to_cpu(tmp);
> -
> -	return ret;
> -}
> -
> -/**
> - * read_ec_until_not_busy() - Read from EC status byte until it reads not busy.
> - * @st: Pointer to state information for device.
> - *
> - * This function reads EC status until its busy bit gets cleared. It does not
> - * wait indefinitely and returns -EIO if the EC status is still busy after a
> - * few hundreds milliseconds.
> - *
> - * Return: 8-bit status if ok, -EIO on error
> - */
> -static int read_ec_until_not_busy(struct cros_ec_accel_legacy_state *st)
> -{
> -	struct cros_ec_device *ec = st->ec;
> -	u8 status;
> -	int attempts = 0;
> -
> -	ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
> -	while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) {
> -		/* Give up after enough attempts, return error. */
> -		if (attempts++ >= 50)
> -			return -EIO;
> -
> -		/* Small delay every so often. */
> -		if (attempts % 5 == 0)
> -			msleep(25);
> -
> -		ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
> -	}
> -
> -	return status;
> -}
> -
> -/**
> - * read_ec_accel_data_unsafe() - Read acceleration data from EC shared memory.
> - * @st:        Pointer to state information for device.
> - * @scan_mask: Bitmap of the sensor indices to scan.
> - * @data:      Location to store data.
> - *
> - * This is the unsafe function for reading the EC data. It does not guarantee
> - * that the EC will not modify the data as it is being read in.
> - */
> -static void read_ec_accel_data_unsafe(struct cros_ec_accel_legacy_state *st,
> -				      unsigned long scan_mask, s16 *data)
> -{
> -	int i = 0;
> -	int num_enabled = bitmap_weight(&scan_mask, MAX_AXIS);
> -
> -	/* Read all sensors enabled in scan_mask. Each value is 2 bytes. */
> -	while (num_enabled--) {
> -		i = find_next_bit(&scan_mask, MAX_AXIS, i);
> -		ec_cmd_read_u16(st->ec,
> -				EC_MEMMAP_ACC_DATA +
> -				sizeof(s16) *
> -				(1 + i + st->sensor_num * MAX_AXIS),
> -				data);
> -		*data *= st->sign[i];
> -		i++;
> -		data++;
> -	}
> -}
> -
> -/**
> - * read_ec_accel_data() - Read acceleration data from EC shared memory.
> - * @st:        Pointer to state information for device.
> - * @scan_mask: Bitmap of the sensor indices to scan.
> - * @data:      Location to store data.
> - *
> - * This is the safe function for reading the EC data. It guarantees that
> - * the data sampled was not modified by the EC while being read.
> - *
> - * Return: 0 if ok, -ve on error
> - */
> -static int read_ec_accel_data(struct cros_ec_accel_legacy_state *st,
> -			      unsigned long scan_mask, s16 *data)
> -{
> -	u8 samp_id = 0xff;
> -	u8 status = 0;
> -	int ret;
> -	int attempts = 0;
> -
> -	/*
> -	 * Continually read all data from EC until the status byte after
> -	 * all reads reflects that the EC is not busy and the sample id
> -	 * matches the sample id from before all reads. This guarantees
> -	 * that data read in was not modified by the EC while reading.
> -	 */
> -	while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT |
> -			  EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) {
> -		/* If we have tried to read too many times, return error. */
> -		if (attempts++ >= 5)
> -			return -EIO;
> -
> -		/* Read status byte until EC is not busy. */
> -		ret = read_ec_until_not_busy(st);
> -		if (ret < 0)
> -			return ret;
> -		status = ret;
> -
> -		/*
> -		 * Store the current sample id so that we can compare to the
> -		 * sample id after reading the data.
> -		 */
> -		samp_id = status & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK;
> -
> -		/* Read all EC data, format it, and store it into data. */
> -		read_ec_accel_data_unsafe(st, scan_mask, data);
> -
> -		/* Read status byte. */
> -		ec_cmd_read_u8(st->ec, EC_MEMMAP_ACC_STATUS, &status);
> -	}
> -
> -	return 0;
> -}
> -
>  static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
>  				     struct iio_chan_spec const *chan,
>  				     int *val, int *val2, long mask)
>  {
> -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> +	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
>  	s16 data = 0;
> -	int ret = IIO_VAL_INT;
> +	int ret;
> +	int idx = chan->scan_index;
> +
> +	mutex_lock(&st->cmd_lock);
>  
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
> -		ret = read_ec_accel_data(st, (1 << chan->scan_index), &data);
> -		if (ret)
> -			return ret;
> +		ret = st->read_ec_sensors_data(indio_dev, 1 << idx, &data);
> +		if (ret < 0)
> +			break;
> +		ret = IIO_VAL_INT;
>  		*val = data;
> -		return IIO_VAL_INT;
> +		break;
>  	case IIO_CHAN_INFO_SCALE:
> +		WARN_ON(st->type != MOTIONSENSE_TYPE_ACCEL);
>  		*val = 0;
>  		*val2 = ACCEL_LEGACY_NSCALE;
> -		return IIO_VAL_INT_PLUS_NANO;
> +		ret = IIO_VAL_INT_PLUS_NANO;
> +		break;
>  	case IIO_CHAN_INFO_CALIBBIAS:
>  		/* Calibration not supported. */
>  		*val = 0;
> -		return IIO_VAL_INT;
> +		ret = IIO_VAL_INT;
> +		break;
>  	default:
> -		return -EINVAL;
> +		ret = cros_ec_sensors_core_read(st, chan, val, val2,
> +				mask);
> +		break;
>  	}
> +	mutex_unlock(&st->cmd_lock);
> +
> +	return ret;
>  }
>  
>  static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
> @@ -231,86 +92,14 @@ static const struct iio_info cros_ec_accel_legacy_info = {
>  	.write_raw = &cros_ec_accel_legacy_write,
>  };
>  
> -/**
> - * cros_ec_accel_legacy_capture() - The trigger handler function
> - * @irq: The interrupt number.
> - * @p:   Private data - always a pointer to the poll func.
> - *
> - * On a trigger event occurring, if the pollfunc is attached then this
> - * handler is called as a threaded interrupt (and hence may sleep). It
> - * is responsible for grabbing data from the device and pushing it into
> - * the associated buffer.
> - *
> - * Return: IRQ_HANDLED
> +/*
> + * Present the channel using HTML5 standard:
> + * need to invert X and Y and invert some lid axis.
>   */
> -static irqreturn_t cros_ec_accel_legacy_capture(int irq, void *p)
> -{
> -	struct iio_poll_func *pf = p;
> -	struct iio_dev *indio_dev = pf->indio_dev;
> -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> -
> -	/* Clear capture data. */
> -	memset(st->capture_data, 0, sizeof(st->capture_data));
> -
> -	/*
> -	 * Read data based on which channels are enabled in scan mask. Note
> -	 * that on a capture we are always reading the calibrated data.
> -	 */
> -	read_ec_accel_data(st, *indio_dev->active_scan_mask, st->capture_data);
> -
> -	iio_push_to_buffers_with_timestamp(indio_dev, (void *)st->capture_data,
> -					   iio_get_time_ns(indio_dev));
> -
> -	/*
> -	 * Tell the core we are done with this trigger and ready for the
> -	 * next one.
> -	 */
> -	iio_trigger_notify_done(indio_dev->trig);
> -
> -	return IRQ_HANDLED;
> -}
> -
> -static char *cros_ec_accel_legacy_loc_strings[] = {
> -	[MOTIONSENSE_LOC_BASE] = "base",
> -	[MOTIONSENSE_LOC_LID] = "lid",
> -	[MOTIONSENSE_LOC_MAX] = "unknown",
> -};
> -
> -static ssize_t cros_ec_accel_legacy_loc(struct iio_dev *indio_dev,
> -					uintptr_t private,
> -					const struct iio_chan_spec *chan,
> -					char *buf)
> -{
> -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> -
> -	return sprintf(buf, "%s\n",
> -		       cros_ec_accel_legacy_loc_strings[st->sensor_num +
> -							MOTIONSENSE_LOC_BASE]);
> -}
> -
> -static ssize_t cros_ec_accel_legacy_id(struct iio_dev *indio_dev,
> -				       uintptr_t private,
> -				       const struct iio_chan_spec *chan,
> -				       char *buf)
> -{
> -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> -
> -	return sprintf(buf, "%d\n", st->sensor_num);
> -}
> -
> -static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
> -	{
> -		.name = "id",
> -		.shared = IIO_SHARED_BY_ALL,
> -		.read = cros_ec_accel_legacy_id,
> -	},
> -	{
> -		.name = "location",
> -		.shared = IIO_SHARED_BY_ALL,
> -		.read = cros_ec_accel_legacy_loc,
> -	},
> -	{ }
> -};
> +#define CROS_EC_ACCEL_ROTATE_AXIS(_axis)				\
> +	((_axis) == CROS_EC_SENSOR_Z ? CROS_EC_SENSOR_Z :		\
> +	 ((_axis) == CROS_EC_SENSOR_X ? CROS_EC_SENSOR_Y :		\
> +	  CROS_EC_SENSOR_X))
>  
>  #define CROS_EC_ACCEL_LEGACY_CHAN(_axis)				\
>  	{								\
> @@ -321,28 +110,28 @@ static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
>  			BIT(IIO_CHAN_INFO_RAW) |			\
>  			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
>  		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
> -		.ext_info = cros_ec_accel_legacy_ext_info,		\
> +		.ext_info = cros_ec_sensors_ext_info,			\
>  		.scan_type = {						\
>  			.sign = 's',					\
> -			.realbits = 16,					\
> -			.storagebits = 16,				\
> +			.realbits = CROS_EC_SENSOR_BITS,		\
> +			.storagebits = CROS_EC_SENSOR_BITS,		\
>  		},							\
> +		.scan_index = CROS_EC_ACCEL_ROTATE_AXIS(_axis),		\
>  	}								\
>  
> -static struct iio_chan_spec ec_accel_channels[] = {
> -	CROS_EC_ACCEL_LEGACY_CHAN(X),
> -	CROS_EC_ACCEL_LEGACY_CHAN(Y),
> -	CROS_EC_ACCEL_LEGACY_CHAN(Z),
> -	IIO_CHAN_SOFT_TIMESTAMP(MAX_AXIS)
> +static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = {
> +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_X),
> +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Y),
> +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Z),
> +		IIO_CHAN_SOFT_TIMESTAMP(CROS_EC_SENSOR_MAX_AXIS)
>  };
>  
>  static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
> -	struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
>  	struct iio_dev *indio_dev;
> -	struct cros_ec_accel_legacy_state *state;
> +	struct cros_ec_sensors_core_state *state;
>  	int ret;
>  
>  	if (!ec || !ec->ec_dev) {
> @@ -350,46 +139,29 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	if (!ec->ec_dev->cmd_readmem) {
> -		dev_warn(&pdev->dev, "EC does not support direct reads.\n");
> -		return -EINVAL;
> -	}
> -
>  	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
>  	if (!indio_dev)
>  		return -ENOMEM;
>  
> -	platform_set_drvdata(pdev, indio_dev);
> -	state = iio_priv(indio_dev);
> -	state->ec = ec->ec_dev;
> -	state->sensor_num = sensor_platform->sensor_num;
> -
> -	indio_dev->dev.parent = dev;
> -	indio_dev->name = pdev->name;
> -	indio_dev->channels = ec_accel_channels;
> -	/*
> -	 * Present the channel using HTML5 standard:
> -	 * need to invert X and Y and invert some lid axis.
> -	 */
> -	ec_accel_channels[X].scan_index = Y;
> -	ec_accel_channels[Y].scan_index = X;
> -	ec_accel_channels[Z].scan_index = Z;
> +	ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
> +	if (ret)
> +		return ret;
>  
> -	state->sign[Y] = 1;
> +	indio_dev->info = &cros_ec_accel_legacy_info;
> +	state = iio_priv(indio_dev);
>  
> -	if (state->sensor_num == MOTIONSENSE_LOC_LID)
> -		state->sign[X] = state->sign[Z] = -1;
> -	else
> -		state->sign[X] = state->sign[Z] = 1;
> +	state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
>  
> -	indio_dev->num_channels = ARRAY_SIZE(ec_accel_channels);
> -	indio_dev->dev.parent = &pdev->dev;
> -	indio_dev->info = &cros_ec_accel_legacy_info;
> -	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = cros_ec_accel_legacy_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(cros_ec_accel_legacy_channels);
> +	/* The lid sensor needs to be presented inverted. */
> +	if (state->loc == MOTIONSENSE_LOC_LID) {
> +		state->sign[CROS_EC_SENSOR_X] = -1;
> +		state->sign[CROS_EC_SENSOR_Z] = -1;
> +	}
>  
>  	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
> -					      cros_ec_accel_legacy_capture,
> -					      NULL);
> +			cros_ec_sensors_capture, NULL);
>  	if (ret)
>  		return ret;
>  
> 

Re: [PATCH v6 3/4] iio: cros_ec_accel_legacy: Use cros_ec_sensors_core

[Jonathan Cameron]

On Tue, 16 Jul 2019 10:46:44 +0200
Enric Balletbo i Serra <enric.balletbo@collabora.com> wrote:

> On 16/7/19 1:14, Gwendal Grignou wrote:
> > Remove duplicate code in cros-ec-accel-legacy,
> > use cros-ec-sensors-core functions and structures when possible.
> > 
> > On glimmer, check the 2 accelerometers are presented and working.
> > 
> > Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> > Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>  
> 
> As the mutex problem is fixed:
> 
> Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> 
Applied,

Thanks,

Jonathan

> > ---
> >  drivers/iio/accel/Kconfig                |   4 +-
> >  drivers/iio/accel/cros_ec_accel_legacy.c | 336 ++++-------------------
> >  2 files changed, 55 insertions(+), 285 deletions(-)
> > 
> > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> > index 62a970a20219..7d0848f9ea45 100644
> > --- a/drivers/iio/accel/Kconfig
> > +++ b/drivers/iio/accel/Kconfig
> > @@ -201,9 +201,7 @@ config HID_SENSOR_ACCEL_3D
> >  
> >  config IIO_CROS_EC_ACCEL_LEGACY
> >  	tristate "ChromeOS EC Legacy Accelerometer Sensor"
> > -	select IIO_BUFFER
> > -	select IIO_TRIGGERED_BUFFER
> > -	select CROS_EC_LPC_REGISTER_DEVICE
> > +	depends on IIO_CROS_EC_SENSORS_CORE
> >  	help
> >  	  Say yes here to get support for accelerometers on Chromebook using
> >  	  legacy EC firmware.
> > diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
> > index ad19d9c716f4..f65578c65a1c 100644
> > --- a/drivers/iio/accel/cros_ec_accel_legacy.c
> > +++ b/drivers/iio/accel/cros_ec_accel_legacy.c
> > @@ -12,6 +12,7 @@
> >  #include <linux/delay.h>
> >  #include <linux/device.h>
> >  #include <linux/iio/buffer.h>
> > +#include <linux/iio/common/cros_ec_sensors_core.h>
> >  #include <linux/iio/iio.h>
> >  #include <linux/iio/kfifo_buf.h>
> >  #include <linux/iio/trigger_consumer.h>
> > @@ -25,191 +26,51 @@
> >  
> >  #define DRV_NAME	"cros-ec-accel-legacy"
> >  
> > +#define CROS_EC_SENSOR_LEGACY_NUM 2
> >  /*
> >   * Sensor scale hard coded at 10 bits per g, computed as:
> >   * g / (2^10 - 1) = 0.009586168; with g = 9.80665 m.s^-2
> >   */
> >  #define ACCEL_LEGACY_NSCALE 9586168
> >  
> > -/* Indices for EC sensor values. */
> > -enum {
> > -	X,
> > -	Y,
> > -	Z,
> > -	MAX_AXIS,
> > -};
> > -
> > -/* State data for cros_ec_accel_legacy iio driver. */
> > -struct cros_ec_accel_legacy_state {
> > -	struct cros_ec_device *ec;
> > -
> > -	/*
> > -	 * Array holding data from a single capture. 2 bytes per channel
> > -	 * for the 3 channels plus the timestamp which is always last and
> > -	 * 8-bytes aligned.
> > -	 */
> > -	s16 capture_data[8];
> > -	s8 sign[MAX_AXIS];
> > -	u8 sensor_num;
> > -};
> > -
> > -static int ec_cmd_read_u8(struct cros_ec_device *ec, unsigned int offset,
> > -			  u8 *dest)
> > -{
> > -	return ec->cmd_readmem(ec, offset, 1, dest);
> > -}
> > -
> > -static int ec_cmd_read_u16(struct cros_ec_device *ec, unsigned int offset,
> > -			   u16 *dest)
> > -{
> > -	__le16 tmp;
> > -	int ret = ec->cmd_readmem(ec, offset, 2, &tmp);
> > -
> > -	*dest = le16_to_cpu(tmp);
> > -
> > -	return ret;
> > -}
> > -
> > -/**
> > - * read_ec_until_not_busy() - Read from EC status byte until it reads not busy.
> > - * @st: Pointer to state information for device.
> > - *
> > - * This function reads EC status until its busy bit gets cleared. It does not
> > - * wait indefinitely and returns -EIO if the EC status is still busy after a
> > - * few hundreds milliseconds.
> > - *
> > - * Return: 8-bit status if ok, -EIO on error
> > - */
> > -static int read_ec_until_not_busy(struct cros_ec_accel_legacy_state *st)
> > -{
> > -	struct cros_ec_device *ec = st->ec;
> > -	u8 status;
> > -	int attempts = 0;
> > -
> > -	ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
> > -	while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) {
> > -		/* Give up after enough attempts, return error. */
> > -		if (attempts++ >= 50)
> > -			return -EIO;
> > -
> > -		/* Small delay every so often. */
> > -		if (attempts % 5 == 0)
> > -			msleep(25);
> > -
> > -		ec_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status);
> > -	}
> > -
> > -	return status;
> > -}
> > -
> > -/**
> > - * read_ec_accel_data_unsafe() - Read acceleration data from EC shared memory.
> > - * @st:        Pointer to state information for device.
> > - * @scan_mask: Bitmap of the sensor indices to scan.
> > - * @data:      Location to store data.
> > - *
> > - * This is the unsafe function for reading the EC data. It does not guarantee
> > - * that the EC will not modify the data as it is being read in.
> > - */
> > -static void read_ec_accel_data_unsafe(struct cros_ec_accel_legacy_state *st,
> > -				      unsigned long scan_mask, s16 *data)
> > -{
> > -	int i = 0;
> > -	int num_enabled = bitmap_weight(&scan_mask, MAX_AXIS);
> > -
> > -	/* Read all sensors enabled in scan_mask. Each value is 2 bytes. */
> > -	while (num_enabled--) {
> > -		i = find_next_bit(&scan_mask, MAX_AXIS, i);
> > -		ec_cmd_read_u16(st->ec,
> > -				EC_MEMMAP_ACC_DATA +
> > -				sizeof(s16) *
> > -				(1 + i + st->sensor_num * MAX_AXIS),
> > -				data);
> > -		*data *= st->sign[i];
> > -		i++;
> > -		data++;
> > -	}
> > -}
> > -
> > -/**
> > - * read_ec_accel_data() - Read acceleration data from EC shared memory.
> > - * @st:        Pointer to state information for device.
> > - * @scan_mask: Bitmap of the sensor indices to scan.
> > - * @data:      Location to store data.
> > - *
> > - * This is the safe function for reading the EC data. It guarantees that
> > - * the data sampled was not modified by the EC while being read.
> > - *
> > - * Return: 0 if ok, -ve on error
> > - */
> > -static int read_ec_accel_data(struct cros_ec_accel_legacy_state *st,
> > -			      unsigned long scan_mask, s16 *data)
> > -{
> > -	u8 samp_id = 0xff;
> > -	u8 status = 0;
> > -	int ret;
> > -	int attempts = 0;
> > -
> > -	/*
> > -	 * Continually read all data from EC until the status byte after
> > -	 * all reads reflects that the EC is not busy and the sample id
> > -	 * matches the sample id from before all reads. This guarantees
> > -	 * that data read in was not modified by the EC while reading.
> > -	 */
> > -	while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT |
> > -			  EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) {
> > -		/* If we have tried to read too many times, return error. */
> > -		if (attempts++ >= 5)
> > -			return -EIO;
> > -
> > -		/* Read status byte until EC is not busy. */
> > -		ret = read_ec_until_not_busy(st);
> > -		if (ret < 0)
> > -			return ret;
> > -		status = ret;
> > -
> > -		/*
> > -		 * Store the current sample id so that we can compare to the
> > -		 * sample id after reading the data.
> > -		 */
> > -		samp_id = status & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK;
> > -
> > -		/* Read all EC data, format it, and store it into data. */
> > -		read_ec_accel_data_unsafe(st, scan_mask, data);
> > -
> > -		/* Read status byte. */
> > -		ec_cmd_read_u8(st->ec, EC_MEMMAP_ACC_STATUS, &status);
> > -	}
> > -
> > -	return 0;
> > -}
> > -
> >  static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
> >  				     struct iio_chan_spec const *chan,
> >  				     int *val, int *val2, long mask)
> >  {
> > -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> > +	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
> >  	s16 data = 0;
> > -	int ret = IIO_VAL_INT;
> > +	int ret;
> > +	int idx = chan->scan_index;
> > +
> > +	mutex_lock(&st->cmd_lock);
> >  
> >  	switch (mask) {
> >  	case IIO_CHAN_INFO_RAW:
> > -		ret = read_ec_accel_data(st, (1 << chan->scan_index), &data);
> > -		if (ret)
> > -			return ret;
> > +		ret = st->read_ec_sensors_data(indio_dev, 1 << idx, &data);
> > +		if (ret < 0)
> > +			break;
> > +		ret = IIO_VAL_INT;
> >  		*val = data;
> > -		return IIO_VAL_INT;
> > +		break;
> >  	case IIO_CHAN_INFO_SCALE:
> > +		WARN_ON(st->type != MOTIONSENSE_TYPE_ACCEL);
> >  		*val = 0;
> >  		*val2 = ACCEL_LEGACY_NSCALE;
> > -		return IIO_VAL_INT_PLUS_NANO;
> > +		ret = IIO_VAL_INT_PLUS_NANO;
> > +		break;
> >  	case IIO_CHAN_INFO_CALIBBIAS:
> >  		/* Calibration not supported. */
> >  		*val = 0;
> > -		return IIO_VAL_INT;
> > +		ret = IIO_VAL_INT;
> > +		break;
> >  	default:
> > -		return -EINVAL;
> > +		ret = cros_ec_sensors_core_read(st, chan, val, val2,
> > +				mask);
> > +		break;
> >  	}
> > +	mutex_unlock(&st->cmd_lock);
> > +
> > +	return ret;
> >  }
> >  
> >  static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
> > @@ -231,86 +92,14 @@ static const struct iio_info cros_ec_accel_legacy_info = {
> >  	.write_raw = &cros_ec_accel_legacy_write,
> >  };
> >  
> > -/**
> > - * cros_ec_accel_legacy_capture() - The trigger handler function
> > - * @irq: The interrupt number.
> > - * @p:   Private data - always a pointer to the poll func.
> > - *
> > - * On a trigger event occurring, if the pollfunc is attached then this
> > - * handler is called as a threaded interrupt (and hence may sleep). It
> > - * is responsible for grabbing data from the device and pushing it into
> > - * the associated buffer.
> > - *
> > - * Return: IRQ_HANDLED
> > +/*
> > + * Present the channel using HTML5 standard:
> > + * need to invert X and Y and invert some lid axis.
> >   */
> > -static irqreturn_t cros_ec_accel_legacy_capture(int irq, void *p)
> > -{
> > -	struct iio_poll_func *pf = p;
> > -	struct iio_dev *indio_dev = pf->indio_dev;
> > -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> > -
> > -	/* Clear capture data. */
> > -	memset(st->capture_data, 0, sizeof(st->capture_data));
> > -
> > -	/*
> > -	 * Read data based on which channels are enabled in scan mask. Note
> > -	 * that on a capture we are always reading the calibrated data.
> > -	 */
> > -	read_ec_accel_data(st, *indio_dev->active_scan_mask, st->capture_data);
> > -
> > -	iio_push_to_buffers_with_timestamp(indio_dev, (void *)st->capture_data,
> > -					   iio_get_time_ns(indio_dev));
> > -
> > -	/*
> > -	 * Tell the core we are done with this trigger and ready for the
> > -	 * next one.
> > -	 */
> > -	iio_trigger_notify_done(indio_dev->trig);
> > -
> > -	return IRQ_HANDLED;
> > -}
> > -
> > -static char *cros_ec_accel_legacy_loc_strings[] = {
> > -	[MOTIONSENSE_LOC_BASE] = "base",
> > -	[MOTIONSENSE_LOC_LID] = "lid",
> > -	[MOTIONSENSE_LOC_MAX] = "unknown",
> > -};
> > -
> > -static ssize_t cros_ec_accel_legacy_loc(struct iio_dev *indio_dev,
> > -					uintptr_t private,
> > -					const struct iio_chan_spec *chan,
> > -					char *buf)
> > -{
> > -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> > -
> > -	return sprintf(buf, "%s\n",
> > -		       cros_ec_accel_legacy_loc_strings[st->sensor_num +
> > -							MOTIONSENSE_LOC_BASE]);
> > -}
> > -
> > -static ssize_t cros_ec_accel_legacy_id(struct iio_dev *indio_dev,
> > -				       uintptr_t private,
> > -				       const struct iio_chan_spec *chan,
> > -				       char *buf)
> > -{
> > -	struct cros_ec_accel_legacy_state *st = iio_priv(indio_dev);
> > -
> > -	return sprintf(buf, "%d\n", st->sensor_num);
> > -}
> > -
> > -static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
> > -	{
> > -		.name = "id",
> > -		.shared = IIO_SHARED_BY_ALL,
> > -		.read = cros_ec_accel_legacy_id,
> > -	},
> > -	{
> > -		.name = "location",
> > -		.shared = IIO_SHARED_BY_ALL,
> > -		.read = cros_ec_accel_legacy_loc,
> > -	},
> > -	{ }
> > -};
> > +#define CROS_EC_ACCEL_ROTATE_AXIS(_axis)				\
> > +	((_axis) == CROS_EC_SENSOR_Z ? CROS_EC_SENSOR_Z :		\
> > +	 ((_axis) == CROS_EC_SENSOR_X ? CROS_EC_SENSOR_Y :		\
> > +	  CROS_EC_SENSOR_X))
> >  
> >  #define CROS_EC_ACCEL_LEGACY_CHAN(_axis)				\
> >  	{								\
> > @@ -321,28 +110,28 @@ static const struct iio_chan_spec_ext_info cros_ec_accel_legacy_ext_info[] = {
> >  			BIT(IIO_CHAN_INFO_RAW) |			\
> >  			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
> >  		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
> > -		.ext_info = cros_ec_accel_legacy_ext_info,		\
> > +		.ext_info = cros_ec_sensors_ext_info,			\
> >  		.scan_type = {						\
> >  			.sign = 's',					\
> > -			.realbits = 16,					\
> > -			.storagebits = 16,				\
> > +			.realbits = CROS_EC_SENSOR_BITS,		\
> > +			.storagebits = CROS_EC_SENSOR_BITS,		\
> >  		},							\
> > +		.scan_index = CROS_EC_ACCEL_ROTATE_AXIS(_axis),		\
> >  	}								\
> >  
> > -static struct iio_chan_spec ec_accel_channels[] = {
> > -	CROS_EC_ACCEL_LEGACY_CHAN(X),
> > -	CROS_EC_ACCEL_LEGACY_CHAN(Y),
> > -	CROS_EC_ACCEL_LEGACY_CHAN(Z),
> > -	IIO_CHAN_SOFT_TIMESTAMP(MAX_AXIS)
> > +static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = {
> > +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_X),
> > +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Y),
> > +		CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Z),
> > +		IIO_CHAN_SOFT_TIMESTAMP(CROS_EC_SENSOR_MAX_AXIS)
> >  };
> >  
> >  static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
> >  {
> >  	struct device *dev = &pdev->dev;
> >  	struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
> > -	struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
> >  	struct iio_dev *indio_dev;
> > -	struct cros_ec_accel_legacy_state *state;
> > +	struct cros_ec_sensors_core_state *state;
> >  	int ret;
> >  
> >  	if (!ec || !ec->ec_dev) {
> > @@ -350,46 +139,29 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
> >  		return -EINVAL;
> >  	}
> >  
> > -	if (!ec->ec_dev->cmd_readmem) {
> > -		dev_warn(&pdev->dev, "EC does not support direct reads.\n");
> > -		return -EINVAL;
> > -	}
> > -
> >  	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
> >  	if (!indio_dev)
> >  		return -ENOMEM;
> >  
> > -	platform_set_drvdata(pdev, indio_dev);
> > -	state = iio_priv(indio_dev);
> > -	state->ec = ec->ec_dev;
> > -	state->sensor_num = sensor_platform->sensor_num;
> > -
> > -	indio_dev->dev.parent = dev;
> > -	indio_dev->name = pdev->name;
> > -	indio_dev->channels = ec_accel_channels;
> > -	/*
> > -	 * Present the channel using HTML5 standard:
> > -	 * need to invert X and Y and invert some lid axis.
> > -	 */
> > -	ec_accel_channels[X].scan_index = Y;
> > -	ec_accel_channels[Y].scan_index = X;
> > -	ec_accel_channels[Z].scan_index = Z;
> > +	ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
> > +	if (ret)
> > +		return ret;
> >  
> > -	state->sign[Y] = 1;
> > +	indio_dev->info = &cros_ec_accel_legacy_info;
> > +	state = iio_priv(indio_dev);
> >  
> > -	if (state->sensor_num == MOTIONSENSE_LOC_LID)
> > -		state->sign[X] = state->sign[Z] = -1;
> > -	else
> > -		state->sign[X] = state->sign[Z] = 1;
> > +	state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
> >  
> > -	indio_dev->num_channels = ARRAY_SIZE(ec_accel_channels);
> > -	indio_dev->dev.parent = &pdev->dev;
> > -	indio_dev->info = &cros_ec_accel_legacy_info;
> > -	indio_dev->modes = INDIO_DIRECT_MODE;
> > +	indio_dev->channels = cros_ec_accel_legacy_channels;
> > +	indio_dev->num_channels = ARRAY_SIZE(cros_ec_accel_legacy_channels);
> > +	/* The lid sensor needs to be presented inverted. */
> > +	if (state->loc == MOTIONSENSE_LOC_LID) {
> > +		state->sign[CROS_EC_SENSOR_X] = -1;
> > +		state->sign[CROS_EC_SENSOR_Z] = -1;
> > +	}
> >  
> >  	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
> > -					      cros_ec_accel_legacy_capture,
> > -					      NULL);
> > +			cros_ec_sensors_capture, NULL);
> >  	if (ret)
> >  		return ret;
> >  
> >   

[PATCH v6 4/4] iio: cros_ec_accel_legacy: Add support for veyron-minnie

[Gwendal Grignou]

Veyron minnie embedded controller presents 2 accelerometers using an
older interface. Add function to query the data in cros_ec_accel.

Verify accelerometers on veyron-minnie are presented and working.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/accel/cros_ec_accel_legacy.c | 40 ++++++++++++++++++++++--
 1 file changed, 38 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index f65578c65a1c..39002cb5605d 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -5,7 +5,7 @@
  * Copyright 2017 Google, Inc
  *
  * This driver uses the memory mapper cros-ec interface to communicate
- * with the Chrome OS EC about accelerometer data.
+ * with the Chrome OS EC about accelerometer data or older commands.
  * Accelerometer access is presented through iio sysfs.
  */
 
@@ -33,6 +33,39 @@
  */
 #define ACCEL_LEGACY_NSCALE 9586168
 
+static int cros_ec_accel_legacy_read_cmd(struct iio_dev *indio_dev,
+				  unsigned long scan_mask, s16 *data)
+{
+	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+	int ret;
+	unsigned int i;
+	u8 sensor_num;
+
+	/*
+	 * Read all sensor data through a command.
+	 * Save sensor_num, it is assumed to stay.
+	 */
+	sensor_num = st->param.info.sensor_num;
+	st->param.cmd = MOTIONSENSE_CMD_DUMP;
+	st->param.dump.max_sensor_count = CROS_EC_SENSOR_LEGACY_NUM;
+	ret = cros_ec_motion_send_host_cmd(st,
+			sizeof(st->resp->dump) + CROS_EC_SENSOR_LEGACY_NUM *
+			sizeof(struct ec_response_motion_sensor_data));
+	st->param.info.sensor_num = sensor_num;
+	if (ret != 0) {
+		dev_warn(&indio_dev->dev, "Unable to read sensor data\n");
+		return ret;
+	}
+
+	for_each_set_bit(i, &scan_mask, indio_dev->masklength) {
+		*data = st->resp->dump.sensor[sensor_num].data[i] *
+			st->sign[i];
+		data++;
+	}
+
+	return 0;
+}
+
 static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
 				     struct iio_chan_spec const *chan,
 				     int *val, int *val2, long mask)
@@ -150,7 +183,10 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
 	indio_dev->info = &cros_ec_accel_legacy_info;
 	state = iio_priv(indio_dev);
 
-	state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
+	if (state->ec->cmd_readmem != NULL)
+		state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
+	else
+		state->read_ec_sensors_data = cros_ec_accel_legacy_read_cmd;
 
 	indio_dev->channels = cros_ec_accel_legacy_channels;
 	indio_dev->num_channels = ARRAY_SIZE(cros_ec_accel_legacy_channels);
-- 
2.22.0.510.g264f2c817a-goog