Re: [PATCH v7 2/2] iio: cros_ec: Add lid angle driver

[Enric Balletbo Serra <eballetbo@gmail.com>]

Missatge de Gwendal Grignou <gwendal@chromium.org> del dia dv., 14 de
juny 2019 a les 23:56:
>
> On Sat, May 18, 2019 at 2:53 AM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > On Fri, 17 May 2019 16:38:56 -0700
> > Gwendal Grignou <gwendal@chromium.org> wrote:
> >
> > > Add a IIO driver that reports the angle between the lid and the base for
> > > ChromeOS convertible device.
> > >
> > > Tested on eve with ToT EC firmware.
> > > Check driver is loaded and lid angle is correct.
> > >
> > > Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> > Hi Gwendal.
> >
> > Please do list dependencies in patches.  I think this one is still
> > dependent on the larger set of MFD changes.
> >
> > For my reference
> >
> > Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> >
> > Please do poke if this seems to have gotten lost once the precursors
> > are upstream.
> The large set of MFD changes for update cros_ec_commands.h has landed
> in a immutable branch:
> git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git branch
> ib-mfd-cros-5.3.
>

Jonathan, if you don't want to deal with the big patchset that this
depends and the immutable branch, I can pick the patch and can go
through the chrome-platform tree. I think it is unlikely have merge
conflicts, as these patches only touch cros-ec iio parts and, anyway,
I'll need to deal with the immutable branch because other patches also
depends on the ib.

Thanks,
~ Enric

> Thanks,
> Gwendal.
>
>
> >
> > Thanks,
> >
> > Jonathan
> >
> > > ---
> > > Changes in v7:
> > > - Split patch in two: This is the IIO section.
> > >
> > > Changes in v6:
> > > - Fix lock held in an error path error.
> > >
> > > Changes in v5:
> > > - Remove unnecessary define.
> > > - v4 was the wrong patch file
> > >
> > > Changes in v3:
> > > - Use static channel array, simplify code because index is always 0.
> > >
> > > Changes in v2:
> > > - Fix license, remove driver_module field.
> > >
> > >  drivers/iio/common/cros_ec_sensors/Kconfig    |   9 ++
> > >  drivers/iio/common/cros_ec_sensors/Makefile   |   1 +
> > >  .../cros_ec_sensors/cros_ec_lid_angle.c       | 139 ++++++++++++++++++
> > >  3 files changed, 149 insertions(+)
> > >  create mode 100644 drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c
> > >
> > > diff --git a/drivers/iio/common/cros_ec_sensors/Kconfig b/drivers/iio/common/cros_ec_sensors/Kconfig
> > > index 135f6825903f..aacc2ab9c34f 100644
> > > --- a/drivers/iio/common/cros_ec_sensors/Kconfig
> > > +++ b/drivers/iio/common/cros_ec_sensors/Kconfig
> > > @@ -20,3 +20,12 @@ config IIO_CROS_EC_SENSORS
> > >         Accelerometers, Gyroscope and Magnetometer that are
> > >         presented by the ChromeOS EC Sensor hub.
> > >         Creates an IIO device for each functions.
> > > +
> > > +config IIO_CROS_EC_SENSORS_LID_ANGLE
> > > +     tristate "ChromeOS EC Sensor for lid angle"
> > > +     depends on IIO_CROS_EC_SENSORS_CORE
> > > +     help
> > > +       Module to report the angle between lid and base for some
> > > +       convertible devices.
> > > +       This module is loaded when the EC can calculate the angle between the base
> > > +       and the lid.
> > > diff --git a/drivers/iio/common/cros_ec_sensors/Makefile b/drivers/iio/common/cros_ec_sensors/Makefile
> > > index ec716ff2a775..a35ee232ac07 100644
> > > --- a/drivers/iio/common/cros_ec_sensors/Makefile
> > > +++ b/drivers/iio/common/cros_ec_sensors/Makefile
> > > @@ -4,3 +4,4 @@
> > >
> > >  obj-$(CONFIG_IIO_CROS_EC_SENSORS_CORE) += cros_ec_sensors_core.o
> > >  obj-$(CONFIG_IIO_CROS_EC_SENSORS) += cros_ec_sensors.o
> > > +obj-$(CONFIG_IIO_CROS_EC_SENSORS_LID_ANGLE) += cros_ec_lid_angle.o
> > > 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
> > > new file mode 100644
> > > index 000000000000..876dfd176b0e
> > > --- /dev/null
> > > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c
> > > @@ -0,0 +1,139 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +
> > > +/*
> > > + * cros_ec_lid_angle - Driver for CrOS EC lid angle sensor.
> > > + *
> > > + * Copyright 2018 Google, Inc
> > > + *
> > > + * This driver uses the cros-ec interface to communicate with the Chrome OS
> > > + * EC about counter sensors. Counters are presented through
> > > + * iio sysfs.
> > > + */
> > > +
> > > +#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.h>
> > > +#include <linux/iio/triggered_buffer.h>
> > > +#include <linux/iio/trigger_consumer.h>
> > > +#include <linux/kernel.h>
> > > +#include <linux/mfd/cros_ec.h>
> > > +#include <linux/mfd/cros_ec_commands.h>
> > > +#include <linux/module.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/slab.h>
> > > +
> > > +#define DRV_NAME "cros-ec-lid-angle"
> > > +
> > > +/*
> > > + * One channel for the lid angle, the other for timestamp.
> > > + */
> > > +static const struct iio_chan_spec cros_ec_lid_angle_channels[] = {
> > > +     {
> > > +             .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> > > +             .scan_type.realbits = CROS_EC_SENSOR_BITS,
> > > +             .scan_type.storagebits = CROS_EC_SENSOR_BITS,
> > > +             .scan_type.sign = 'u',
> > > +             .type = IIO_ANGL
> > > +     },
> > > +     IIO_CHAN_SOFT_TIMESTAMP(1)
> > > +};
> > > +
> > > +/* State data for ec_sensors iio driver. */
> > > +struct cros_ec_lid_angle_state {
> > > +     /* Shared by all sensors */
> > > +     struct cros_ec_sensors_core_state core;
> > > +};
> > > +
> > > +static int cros_ec_sensors_read_lid_angle(struct iio_dev *indio_dev,
> > > +                                       unsigned long scan_mask, s16 *data)
> > > +{
> > > +     struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
> > > +     int ret;
> > > +
> > > +     st->param.cmd = MOTIONSENSE_CMD_LID_ANGLE;
> > > +     ret = cros_ec_motion_send_host_cmd(st, sizeof(st->resp->lid_angle));
> > > +     if (ret) {
> > > +             dev_warn(&indio_dev->dev, "Unable to read lid angle\n");
> > > +             return ret;
> > > +     }
> > > +
> > > +     *data = st->resp->lid_angle.value;
> > > +     return 0;
> > > +}
> > > +
> > > +static int cros_ec_lid_angle_read(struct iio_dev *indio_dev,
> > > +                                 struct iio_chan_spec const *chan,
> > > +                                 int *val, int *val2, long mask)
> > > +{
> > > +     struct cros_ec_lid_angle_state *st = iio_priv(indio_dev);
> > > +     s16 data;
> > > +     int ret;
> > > +
> > > +     mutex_lock(&st->core.cmd_lock);
> > > +     ret = cros_ec_sensors_read_lid_angle(indio_dev, 1, &data);
> > > +     if (ret == 0) {
> > > +             *val = data;
> > > +             ret = IIO_VAL_INT;
> > > +     }
> > > +     mutex_unlock(&st->core.cmd_lock);
> > > +     return ret;
> > > +}
> > > +
> > > +static const struct iio_info cros_ec_lid_angle_info = {
> > > +     .read_raw = &cros_ec_lid_angle_read,
> > > +};
> > > +
> > > +static int cros_ec_lid_angle_probe(struct platform_device *pdev)
> > > +{
> > > +     struct device *dev = &pdev->dev;
> > > +     struct iio_dev *indio_dev;
> > > +     struct cros_ec_lid_angle_state *state;
> > > +     int ret;
> > > +
> > > +     indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
> > > +     if (!indio_dev)
> > > +             return -ENOMEM;
> > > +
> > > +     ret = cros_ec_sensors_core_init(pdev, indio_dev, false);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     indio_dev->info = &cros_ec_lid_angle_info;
> > > +     state = iio_priv(indio_dev);
> > > +     indio_dev->channels = cros_ec_lid_angle_channels;
> > > +     indio_dev->num_channels = ARRAY_SIZE(cros_ec_lid_angle_channels);
> > > +
> > > +     state->core.read_ec_sensors_data = cros_ec_sensors_read_lid_angle;
> > > +
> > > +     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);
> > > +}
> > > +
> > > +static const struct platform_device_id cros_ec_lid_angle_ids[] = {
> > > +     {
> > > +             .name = DRV_NAME,
> > > +     },
> > > +     { /* sentinel */ }
> > > +};
> > > +MODULE_DEVICE_TABLE(platform, cros_ec_lid_angle_ids);
> > > +
> > > +static struct platform_driver cros_ec_lid_angle_platform_driver = {
> > > +     .driver = {
> > > +             .name   = DRV_NAME,
> > > +             .pm     = &cros_ec_sensors_pm_ops,
> > > +     },
> > > +     .probe          = cros_ec_lid_angle_probe,
> > > +     .id_table       = cros_ec_lid_angle_ids,
> > > +};
> > > +module_platform_driver(cros_ec_lid_angle_platform_driver);
> > > +
> > > +MODULE_DESCRIPTION("ChromeOS EC driver for reporting convertible lid angle.");
> > > +MODULE_LICENSE("GPL v2");
> >