[PATCH v6 0/3] platform/chrome: Support for cros_ec_accel_legacy driver

[PATCH v6 0/3] platform/chrome: Support for cros_ec_accel_legacy driver

[Thierry Escande]

Hi,

This patchset registers the cros_ec_accel_legacy driver if the usual way
of registering the croc_ec sensors hub fails.

Changes in v6:
- Only register accelerometer for the main EC

Changes in v5:
- Remove the driver which is already merged
- Rebased on top of patchset [1]

Changes in v4:
- Use correct bitmask for scale channel specification
- Use precomputed scale factor value

Changes in v3:
- Use kernel-doc notation for function headers
- Add more comment to sensor ID sysfs attribute documentation
- Restore accidentally deleted comment for IIO_CHAN_INFO_CALIBBIAS handling in
  iio_info write_raw() callback

Changes in v2:
- Reorganize code to avoid forward declarations
- Simplify capture buffer declaration (also helps to remove forward
  declarations)
- Make use of iio_push_to_buffers_with_timestamp() and let the
  framework handle timestamp copy into capture buffer
- Added missing sysfs attribute documentation
- Few cosmetic changes here and there


Enric Balletbo i Serra (1):
  platform/chrome: cros_ec_lpc: Register the driver if ACPI entry is
    missing.

Thierry Escande (2):
  platform/chrome: cros_ec_lpc: Add support for Google Glimmer
  platform/chrome: Register cros_ec_accel_legacy driver

 drivers/mfd/cros_ec_dev.c             | 53 +++++++++++++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_lpc.c | 41 ++++++++++++++++++++++++++-
 2 files changed, 93 insertions(+), 1 deletion(-)

-- 
2.7.4

[PATCH v6 3/3] platform/chrome: Register cros_ec_accel_legacy driver

[Thierry Escande]

With this patch, the cros_ec_ctl driver will register the legacy
accelerometer driver (named cros_ec_accel_legacy) if it fails to
register sensors through the usual path cros_ec_sensors_register().
This legacy device is present on Chromebook devices with older EC
firmware only supporting deprecated EC commands (Glimmer based devices).

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
 drivers/mfd/cros_ec_dev.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 3c4859d9c3c1..ec518a9f564f 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -389,6 +389,63 @@ static void cros_ec_sensors_register(struct cros_ec_dev *ec)
 	kfree(msg);
 }
 
+#define CROS_EC_SENSOR_LEGACY_NUM 2
+static struct mfd_cell cros_ec_accel_legacy_cells[CROS_EC_SENSOR_LEGACY_NUM];
+
+static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
+{
+	struct cros_ec_device *ec_dev = ec->ec_dev;
+	u8 status;
+	int i, ret;
+	struct cros_ec_sensor_platform
+		sensor_platforms[CROS_EC_SENSOR_LEGACY_NUM];
+
+	/*
+	 * EC that need legacy support are the main EC, directly connected to
+	 * the AP.
+	*/
+	if (ec->cmd_offset != 0)
+		return;
+
+	/*
+	 * Check if EC supports direct memory reads and if EC has
+	 * accelerometers.
+	 */
+	if (!ec_dev->cmd_readmem)
+		return;
+
+	ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1, &status);
+	if (ret < 0) {
+		dev_warn(ec->dev, "EC does not support direct reads.\n");
+		return;
+	}
+
+	/* Check if EC has accelerometers. */
+	if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
+		dev_info(ec->dev, "EC does not have accelerometers.\n");
+		return;
+	}
+
+	/*
+	 * Register 2 accelerometers
+	 */
+	for (i = 0; i < CROS_EC_SENSOR_LEGACY_NUM; i++) {
+		cros_ec_accel_legacy_cells[i].name = "cros-ec-accel-legacy";
+		sensor_platforms[i].sensor_num = i;
+		cros_ec_accel_legacy_cells[i].id = i;
+		cros_ec_accel_legacy_cells[i].platform_data =
+			&sensor_platforms[i];
+		cros_ec_accel_legacy_cells[i].pdata_size =
+			sizeof(struct cros_ec_sensor_platform);
+	}
+	ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
+			      cros_ec_accel_legacy_cells,
+			      CROS_EC_SENSOR_LEGACY_NUM,
+			      NULL, 0, NULL);
+	if (ret)
+		dev_err(ec_dev->dev, "failed to add EC sensors\n");
+}
+
 static int ec_device_probe(struct platform_device *pdev)
 {
 	int retval = -ENOMEM;
@@ -436,6 +493,9 @@ static int ec_device_probe(struct platform_device *pdev)
 	/* check whether this EC is a sensor hub. */
 	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
 		cros_ec_sensors_register(ec);
+	else
+		/* Workaroud for older EC firmware */
+		cros_ec_accel_legacy_register(ec);
 
 	/* Take control of the lightbar from the EC. */
 	lb_manual_suspend_ctrl(ec, 1);
-- 
2.14.1

Re: [PATCH v6 3/3] platform/chrome: Register cros_ec_accel_legacy driver

[Gwendal Grignou]

On Fri, Jan 19, 2018 at 3:00 AM, Thierry Escande
<thierry.escande@collabora.com> wrote:
>
> With this patch, the cros_ec_ctl driver will register the legacy
> accelerometer driver (named cros_ec_accel_legacy) if it fails to
> register sensors through the usual path cros_ec_sensors_register().
> This legacy device is present on Chromebook devices with older EC
> firmware only supporting deprecated EC commands (Glimmer based devices).
>
> Signed-off-by: Thierry Escande <thierry.escande@collabora.com>

Tested-by: Gwendal Grignou <gwendal@chromium.org>

Integrated into chromeos kernel [internal CL:891664]
Tested with Glimmer (legacy driver required) and Samus (check driver
is not loaded).
[Retry in text mode only]
>
> ---
>  drivers/mfd/cros_ec_dev.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 60 insertions(+)
>
> diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
> index 3c4859d9c3c1..ec518a9f564f 100644
> --- a/drivers/mfd/cros_ec_dev.c
> +++ b/drivers/mfd/cros_ec_dev.c
> @@ -389,6 +389,63 @@ static void cros_ec_sensors_register(struct cros_ec_dev *ec)
>         kfree(msg);
>  }
>
> +#define CROS_EC_SENSOR_LEGACY_NUM 2
> +static struct mfd_cell cros_ec_accel_legacy_cells[CROS_EC_SENSOR_LEGACY_NUM];
> +
> +static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
> +{
> +       struct cros_ec_device *ec_dev = ec->ec_dev;
> +       u8 status;
> +       int i, ret;
> +       struct cros_ec_sensor_platform
> +               sensor_platforms[CROS_EC_SENSOR_LEGACY_NUM];
> +
> +       /*
> +        * EC that need legacy support are the main EC, directly connected to
> +        * the AP.
> +       */
> +       if (ec->cmd_offset != 0)
> +               return;
> +
> +       /*
> +        * Check if EC supports direct memory reads and if EC has
> +        * accelerometers.
> +        */
> +       if (!ec_dev->cmd_readmem)
> +               return;
> +
> +       ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1, &status);
> +       if (ret < 0) {
> +               dev_warn(ec->dev, "EC does not support direct reads.\n");
> +               return;
> +       }
> +
> +       /* Check if EC has accelerometers. */
> +       if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
> +               dev_info(ec->dev, "EC does not have accelerometers.\n");
> +               return;
> +       }
> +
> +       /*
> +        * Register 2 accelerometers
> +        */
> +       for (i = 0; i < CROS_EC_SENSOR_LEGACY_NUM; i++) {
> +               cros_ec_accel_legacy_cells[i].name = "cros-ec-accel-legacy";
> +               sensor_platforms[i].sensor_num = i;
> +               cros_ec_accel_legacy_cells[i].id = i;
> +               cros_ec_accel_legacy_cells[i].platform_data =
> +                       &sensor_platforms[i];
> +               cros_ec_accel_legacy_cells[i].pdata_size =
> +                       sizeof(struct cros_ec_sensor_platform);
> +       }
> +       ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
> +                             cros_ec_accel_legacy_cells,
> +                             CROS_EC_SENSOR_LEGACY_NUM,
> +                             NULL, 0, NULL);
> +       if (ret)
> +               dev_err(ec_dev->dev, "failed to add EC sensors\n");
> +}
> +
>  static int ec_device_probe(struct platform_device *pdev)
>  {
>         int retval = -ENOMEM;
> @@ -436,6 +493,9 @@ static int ec_device_probe(struct platform_device *pdev)
>         /* check whether this EC is a sensor hub. */
>         if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
>                 cros_ec_sensors_register(ec);
> +       else
> +               /* Workaroud for older EC firmware */
> +               cros_ec_accel_legacy_register(ec);
>
>         /* Take control of the lightbar from the EC. */
>         lb_manual_suspend_ctrl(ec, 1);
> --
> 2.14.1
>