[PATCH v4 1/4] Input: ads7846 - Convert to use software nodes
Dmitry Torokhov
dmitry.torokhov at gmail.com
Mon May 8 14:24:54 PDT 2023
On Mon, May 08, 2023 at 11:20:06PM +0200, Linus Walleij wrote:
> The Nokia 770 is using GPIOs from the global numberspace on the
> CBUS node to pass down to the LCD controller. This regresses when we
> let the OMAP GPIO driver use dynamic GPIO base.
>
> The Nokia 770 now has dynamic allocation of IRQ numbers, so this
> needs to be fixed for it to work.
>
> As this is the only user of LCD MIPID we can easily augment the
> driver to use a GPIO descriptor instead and resolve the issue.
>
> The platform data .shutdown() callback wasn't even used in the
> code, but we encode a shutdown asserting RESET in the remove()
> callback for completeness sake.
>
> The CBUS also has the ADS7846 touchscreen attached.
>
> Populate the devices on the Nokia 770 CBUS I2C using software
> nodes instead of platform data quirks. This includes the LCD
> and the ADS7846 touchscreen so the conversion just brings the LCD
> along with it as software nodes is an all-or-nothing design
> pattern.
>
> The ADS7846 has some limited support for using GPIO descriptors,
> let's convert it over completely to using device properties and then
> fix all remaining boardfile users to provide all platform data using
> software nodes.
>
> Dump the of includes and of_match_ptr() in the ADS7846 driver as part
> of the job.
>
> Since we have to move ADS7846 over to obtaining the GPIOs it is
> using exclusively from descriptors, we provide descriptor tables
> for the two remaining in-kernel boardfiles using ADS7846:
>
> - PXA Spitz
> - MIPS Alchemy DB1000 development board
>
> It was too hard for me to include software node conversion of
> these two remaining users at this time: the spitz is using a
> hscync callback in the platform data that would require further
> GPIO descriptor conversion of the Spitz, and moving the hsync
> callback down into the driver: it will just become too big of
> a job, but it can be done separately.
>
> The MIPS Alchemy DB1000 is simply something I cannot test, so take
> the easier approach of just providing some GPIO descriptors in
> this case as I don't want the patch to grow too intrusive.
>
> As we see that several device trees have incorrect polarity flags
> and just expect to bypass the gpiolib polarity handling, fix up
> all device trees too, in a separate patch.
>
> Suggested-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
> Fixes: 92bf78b33b0b ("gpio: omap: use dynamic allocation of base")
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
> ---
> ChangeLog v3->v4:
> - Fix all board file polarity flags to be active low, because
> this pendown signal is active low.
> - Fix all erroneous device trees too.
> - Drop some unnecessary commas.
> ChangeLog v2->v3:
> - Drop leftover OF ifdefs no longer needed and causing compile
> errors.
> ---
> arch/arm/mach-omap1/board-nokia770.c | 98 +++++++++++++++++----------
> arch/arm/mach-pxa/spitz.c | 11 +++-
> arch/mips/alchemy/devboards/db1000.c | 11 +++-
> drivers/input/touchscreen/ads7846.c | 113 ++++++++++++--------------------
For input:
Acked-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
In general:
Reviewed-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Thanks.
--
Dmitry
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