Hi Dimitry,
On Wed, Jun 19, 2024 at 06:12:45PM -0700, Dmitry Torokhov wrote:
> Hi Stefan,
>
> On Wed, Apr 17, 2024 at 11:05:27AM +0200, Stefan Eichenberger wrote:
> > From: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
> >
> > Add support for poweroff-sleep to the Atmel maXTouch driver. This allows
> > us to power off the input device entirely and only power it on when it
> > is opened. This will also automatically power it off when we suspend the
> > system.
> >
> > Signed-off-by: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
> > ---
> > drivers/input/touchscreen/atmel_mxt_ts.c | 71 +++++++++++++++++++-----
> > 1 file changed, 57 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> > index 7c807d1f1f9b..f92808be3f5b 100644
> > --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> > @@ -317,6 +317,7 @@ struct mxt_data {
> > struct gpio_desc *reset_gpio;
> > struct gpio_desc *wake_gpio;
> > bool use_retrigen_workaround;
> > + bool poweroff_sleep;
>
> Why is this separate from "enum mxt_suspend_mode suspend_mode"? Can we
> make MXT_SUSPEND_POWEROFF and use it in mxt_start() and others? It still
> can be driven by the "atmel,poweroff-sleep" device property.
I agree and will change this in the next version.
> >
> > /* Cached parameters from object table */
> > u16 T5_address;
> > @@ -2277,6 +2278,19 @@ static void mxt_config_cb(const struct firmware *cfg, void *ctx)
> > release_firmware(cfg);
> > }
> >
> > +static int mxt_initialize_after_resume(struct mxt_data *data)
> > +{
> > + const struct firmware *fw;
> > +
> > + mxt_acquire_irq(data);
> > +
> > + firmware_request_nowarn(&fw, MXT_CFG_NAME, &data->client->dev);
> > +
> > + mxt_config_cb(fw, data);
>
> Is this really required? As far as I know all maXTouch controllers have
> NVRAM for their configs and should not lose configuration even if power
> is cut off. In fact, the whole automatic request of firmware/config upon
> probe I think was a mistake and I would like to get rid of it. In fact,
> on Chrome OS the version of the driver in use does not do that and
> instead relies on userspace to check if firmware update is needed.
>
> If this is actually required you need to add error handling.
You are right, and the configuration goes to non-volatile memory, so
this is not needed. I will remove the firmware loading here and improve
the error handling. I will keep the firmware loading in the initial
probe for now, to be consistent with the non poweroff-sleep version.
Regards,
Stefan
