Re: [PATCH 01/13] mfd: cros_ec: Add sensor_count and make check_features public

[Gwendal Grignou]

Sounds good to me, I will make the change in rev2.

On Mon, Sep 30, 2019 at 6:15 AM Enric Balletbo i Serra
<enric.balletbo@xxxxxxxxxxxxx> wrote:
>
> Hi Gwendal,
>
> Many thanks for the patches.
>
> On 22/9/19 19:50, Gwendal Grignou wrote:
> > Add a new function to return the number of MEMS sensors available in a
> > ChromeOS Embedded Controller.
> > It uses MOTIONSENSE_CMD_DUMP if available or a specific memory map ACPI
> > registers to find out.
> >
> > Also, make check_features public as it can be useful for other drivers
> > to know whant the Embedded Controller supports.
> >
> > Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> > ---
> >  drivers/mfd/cros_ec_dev.c   | 61 ++++++++++++++++++++++++++++++++++++-
> >  include/linux/mfd/cros_ec.h | 17 +++++++++++
> >  2 files changed, 77 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
> > index 6e6dfd6c1871..3be80183ccaa 100644
> > --- a/drivers/mfd/cros_ec_dev.c
> > +++ b/drivers/mfd/cros_ec_dev.c
> > @@ -112,7 +112,7 @@ static const struct mfd_cell cros_ec_vbc_cells[] = {
> >       { .name = "cros-ec-vbc", }
> >  };
> >
> > -static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
> > +int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
> >  {
> >       struct cros_ec_command *msg;
> >       int ret;
> > @@ -143,12 +143,71 @@ static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
> >
> >       return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);
> >  }
> > +EXPORT_SYMBOL_GPL(cros_ec_check_features);
> >
> >  static void cros_ec_class_release(struct device *dev)
> >  {
> >       kfree(to_cros_ec_dev(dev));
> >  }
> >
> > +int cros_ec_get_sensor_count(struct cros_ec_dev *ec)
> > +{
> > +     /*
> > +      * Issue a command to get the number of sensor reported.
> > +      * If not supported, check for legacy mode.
> > +      */
> > +     int ret, sensor_count;
> > +     struct ec_params_motion_sense *params;
> > +     struct ec_response_motion_sense *resp;
> > +     struct cros_ec_command *msg;
> > +     struct cros_ec_device *ec_dev = ec->ec_dev;
> > +     u8 status;
> > +
> > +     msg = kzalloc(sizeof(struct cros_ec_command) +
> > +                     max(sizeof(*params), sizeof(*resp)), GFP_KERNEL);
> > +     if (msg == NULL)
> > +             return -ENOMEM;
> > +
> > +     msg->version = 1;
> > +     msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
> > +     msg->outsize = sizeof(*params);
> > +     msg->insize = sizeof(*resp);
> > +
> > +     params = (struct ec_params_motion_sense *)msg->data;
> > +     params->cmd = MOTIONSENSE_CMD_DUMP;
> > +
> > +     ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
> > +     if (ret < 0) {
> > +             sensor_count = ret;
> > +     } else if (msg->result != EC_RES_SUCCESS) {
> > +             sensor_count = -EPROTO;
> > +     } else {
> > +             resp = (struct ec_response_motion_sense *)msg->data;
> > +             sensor_count = resp->dump.sensor_count;
> > +     }
> > +     kfree(msg);
> > +
> > +     /*
> > +      * Check legacy mode: Let's find out if sensors are accessible
> > +      * via LPC interface.
> > +      */
> > +     if (sensor_count == -EPROTO &&
> > +         ec->cmd_offset == 0 &&
> > +         ec_dev->cmd_readmem) {
> > +             ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,
> > +                             1, &status);
> > +             if ((ret >= 0) &&
> > +                 (status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
> > +                     /*
> > +                      * We have 2 sensors, one in the lid, one in the base.
> > +                      */
> > +                     sensor_count = 2;
> > +             }
> > +     }
> > +     return sensor_count;
> > +}
> > +EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);
> > +
> >  static void cros_ec_sensors_register(struct cros_ec_dev *ec)
> >  {
> >       /*
> > diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
> > index 61c2875c2a40..578e0bbcafdc 100644
> > --- a/include/linux/mfd/cros_ec.h
> > +++ b/include/linux/mfd/cros_ec.h
> > @@ -32,4 +32,21 @@ struct cros_ec_dev {
> >
> >  #define to_cros_ec_dev(dev)  container_of(dev, struct cros_ec_dev, class_dev)
> >
> > +/**
> > + * cros_ec_check_features - Test for the presence of EC features
> > + *
> > + * Call this function to test whether the ChromeOS EC supports a feature.
> > + *
> > + * @ec_dev: EC device
> > + * @msg: One of ec_feature_code values
> > + * @return: 1 if supported, 0 if not
> > + */
> > +int cros_ec_check_features(struct cros_ec_dev *ec, int feature);
> > +
> > +/*
> > + * Return the number of MEMS sensors supported.
> > + * Return < 0 in case of error.
> > + */
> > +int cros_ec_get_sensor_count(struct cros_ec_dev *ec);
> > +
>
> I am wondering if we should take this opportunity to move these two functions
> from drivers/mfd/cros_ec_dev to drivers/platform/chrome/cros_ec_proto.c and
> include/linux/platform_data/cros_ec_proto.h
>
> I think this part is more suitable for core part that actually resides in
> platform/chrome than the mfd device itself. What do you think? Do you see any
> problem on doing this?
>
> Thanks,
>  Enric
>
> >  #endif /* __LINUX_MFD_CROS_EC_H */
> >