[PATCH v5 1/2] gpio: i2c-gpio: Drop use of dm_gpio_set_dir()

[Simon Glass]

Hi Harm,

On Mon, 8 Mar 2021 at 14:07, Harm Berntsen <harm.berntsen at nedap.com> wrote:
>
> The dm_gpio_set_dir_flags does a bitwise OR with the new flags. This
> means that the i2c driver cannot switch the pin from input to output or
> vice versa. check_dir_flags fails here:
>
> check_dir_flags: flags 0x6 has GPIOD_IS_OUT and GPIOD_IS_IN
>
> On my board, removing the logical OR in dm_gpio_set_dir_flags fixes the
> issue. The _dm_gpio_set_dir_flags function stores the passed flags
> directly into the descriptor. This means that by removing the logical
> OR all the existing flags will be lost which is also not what we want.
>
> So the code needs to be able to unset the IN/OUT direction bits. I
> don't feel like I'm familiar enough with the GPIO code to do a good
> suggestion. Maybe Patrick could help us out here?

Ah yes I had forgotten about that little quirk. I will send a new
patch. Thank you for your help.

Regards,
Simon



>
> -----Original Message-----
> From: Simon Glass <sjg at chromium.org>
> To: Harm Berntsen <harm.berntsen at nedap.com>
> Cc: hs at denx.de <hs at denx.de>, trini at konsulko.com <trini at konsulko.com>,
> u-boot at lists.denx.de <u-boot at lists.denx.de>, patrick.delaunay at st.com
> <patrick.delaunay at st.com>
> Subject: Re: [PATCH v5 1/2] gpio: i2c-gpio: Drop use of
> dm_gpio_set_dir()
> Date: Mon, 08 Mar 2021 10:05:24 -0500
>
> Hi Harm,
>
> On Mon, 8 Mar 2021 at 09:35, Harm Berntsen <harm.berntsen at nedap.com>
> wrote:
> >
> > I've just tested this on top of the current master (90964ab5) and
> > this
> > breaks my board (Kirkwood CPU with MVEBU_GPIO=y and DM_I2C_GPIO=y).
> > I'll do some debugging to see what goes wrong.
>
> Thank you for that.
>
> Once we figure this out we should add a test.
>
> >
> > -----Original Message-----
> > From: Tom Rini <trini at konsulko.com>
> > To: Heiko Schocher <hs at denx.de>, Harm Berntsen
> > <harm.berntsen at nedap.com>
> > Cc: Simon Glass <sjg at chromium.org>, U-Boot Mailing List
> > <u-boot at lists.denx.de>, Patrick Delaunay <patrick.delaunay at st.com>
> > Subject: Re: [PATCH v5 1/2] gpio: i2c-gpio: Drop use of
> > dm_gpio_set_dir()
> > Date: Mon, 08 Mar 2021 08:16:53 -0500
> >
> > On Mon, Mar 08, 2021 at 05:59:45AM +0100, Heiko Schocher wrote:
> > > Hello Simon,
> > >
> > > On 08.03.21 04:45, Simon Glass wrote:
> > > > This is the only driver that uses this function. Update it to use
> > > > the
> > > > alternative which is dm_gpio_set_dir_flags().
> > > >
> > > > Signed-off-by: Simon Glass <sjg at chromium.org>
> > > > ---
> > > >
> > > > (no changes since v1)
> > > >
> > > >  drivers/i2c/i2c-gpio.c | 19 +++++++++----------
> > > >  1 file changed, 9 insertions(+), 10 deletions(-)
> > >
> > > Reviewed-by: Heiko Schocher <hs at denx.de>
> >
> > The series is at:
> > https://patchwork.ozlabs.org/project/uboot/list/?series=232639&state=*
> > and I'd really like to see a tested-by.  Harm, are you able to test
> > this
> > still since you had to fix this area before?  Thanks!
>
> Regards,
> Simon
>