[PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[David Lechner]

This fixes pcs_request_gpio() in the pinctrl-single driver when
bits_per_mux != 0. It appears this was overlooked when the multiple
pins per register feature was added.

Fixes: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure
multiple pins of different modules")

Cc: Tony Lindgren <tony@atomide.com>
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David Lechner <david@lechnology.com>
---
 drivers/pinctrl/pinctrl-single.c | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 3501491..7a5e2f1 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -391,9 +391,25 @@ static int pcs_request_gpio(struct pinctrl_dev *pctldev,
 			|| pin < frange->offset)
 			continue;
 		mux_bytes = pcs->width / BITS_PER_BYTE;
-		data = pcs->read(pcs->base + pin * mux_bytes) & ~pcs->fmask;
-		data |= frange->gpiofunc;
-		pcs->write(data, pcs->base + pin * mux_bytes);
+
+		if (pcs->bits_per_mux) {
+			int byte_num, offset, pin_shift;
+
+			byte_num = (pcs->bits_per_pin * pin) / BITS_PER_BYTE;
+			offset = (byte_num / mux_bytes) * mux_bytes;
+			pin_shift = pin % (pcs->width / pcs->bits_per_pin) *
+				    pcs->bits_per_pin;
+
+			data = pcs->read(pcs->base + offset);
+			data &= ~(pcs->fmask << pin_shift);
+			data |= frange->gpiofunc << pin_shift;
+			pcs->write(data, pcs->base + offset);
+		} else {
+			data = pcs->read(pcs->base + pin * mux_bytes);
+			data &= ~pcs->fmask;
+			data |= frange->gpiofunc;
+			pcs->write(data, pcs->base + pin * mux_bytes);
+		}
 		break;
 	}
 	return 0;
-- 
2.7.4

Re: [PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[Andy Shevchenko]

On Mon, Jan 22, 2018 at 1:03 AM, David Lechner <david@lechnology.com> wrote:
> This fixes pcs_request_gpio() in the pinctrl-single driver when
> bits_per_mux != 0. It appears this was overlooked when the multiple
> pins per register feature was added.
>
> Fixes: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure
> multiple pins of different modules")

One line?

> +                       byte_num = (pcs->bits_per_pin * pin) / BITS_PER_BYTE;
> +                       offset = (byte_num / mux_bytes) * mux_bytes;
> +                       pin_shift = pin % (pcs->width / pcs->bits_per_pin) *
> +                                   pcs->bits_per_pin;

Sounds like playing around pretty well defined macro and functions,
e.g. DIV_ROUND_UP(), round_up().

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[David Lechner]

On 01/22/2018 08:49 AM, Andy Shevchenko wrote:
> On Mon, Jan 22, 2018 at 1:03 AM, David Lechner <david@lechnology.com> wrote:
>> This fixes pcs_request_gpio() in the pinctrl-single driver when
>> bits_per_mux != 0. It appears this was overlooked when the multiple
>> pins per register feature was added.
>>
>> Fixes: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure
>> multiple pins of different modules")
> 
> One line?

One line is more important that wrapping to 75 chars?

> 
>> +                       byte_num = (pcs->bits_per_pin * pin) / BITS_PER_BYTE;
>> +                       offset = (byte_num / mux_bytes) * mux_bytes;
>> +                       pin_shift = pin % (pcs->width / pcs->bits_per_pin) *
>> +                                   pcs->bits_per_pin;
> 
> Sounds like playing around pretty well defined macro and functions,
> e.g. DIV_ROUND_UP(), round_up().
> 

I admit, I just copied existing code (which may be a reason to leave this the
way it is). But, I only see once place to do this:

	offset = round_down(byte_num, mux_bytes);

Did I miss another?

Re: [PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[Andy Shevchenko]

On Mon, Jan 22, 2018 at 7:06 PM, David Lechner <david@lechnology.com> wrote:
> On 01/22/2018 08:49 AM, Andy Shevchenko wrote:
>> On Mon, Jan 22, 2018 at 1:03 AM, David Lechner <david@lechnology.com>
>> wrote:

>>> Fixes: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure
>>> multiple pins of different modules")

>> One line?

> One line is more important that wrapping to 75 chars?

It's *special* line, i.e. tag. Tag per line is a rule I know, did I
miss any new change to that?

>>> +                       byte_num = (pcs->bits_per_pin * pin) /
>>> BITS_PER_BYTE;
>>> +                       offset = (byte_num / mux_bytes) * mux_bytes;
>>> +                       pin_shift = pin % (pcs->width /
>>> pcs->bits_per_pin) *
>>> +                                   pcs->bits_per_pin;

>> Sounds like playing around pretty well defined macro and functions,
>> e.g. DIV_ROUND_UP(), round_up().

> I admit, I just copied existing code (which may be a reason to leave this
> the
> way it is).

Ah, fair enough.

>  But, I only see once place to do this:
>
>         offset = round_down(byte_num, mux_bytes);
>
> Did I miss another?

I meant that you may use macros to make code cleaner. Though, taking
above into consideration, it would be done as a separate patch later.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] pinctrl: pinctrl-single: Fix pcs_request_gpio() when bits_per_mux != 0

[Tony Lindgren]

* Andy Shevchenko <andy.shevchenko@gmail.com> [180123 09:25]:
> On Mon, Jan 22, 2018 at 7:06 PM, David Lechner <david@lechnology.com> wrote:
> > On 01/22/2018 08:49 AM, Andy Shevchenko wrote:
> >> On Mon, Jan 22, 2018 at 1:03 AM, David Lechner <david@lechnology.com>
> >> wrote:
> 
> >>> Fixes: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure
> >>> multiple pins of different modules")
> 
> >> One line?
> 
> > One line is more important that wrapping to 75 chars?
> 
> It's *special* line, i.e. tag. Tag per line is a rule I know, did I
> miss any new change to that?

I think the rule for merge commits is to try to limit them to 75
characters for git log.

> >>> +                       byte_num = (pcs->bits_per_pin * pin) /
> >>> BITS_PER_BYTE;
> >>> +                       offset = (byte_num / mux_bytes) * mux_bytes;
> >>> +                       pin_shift = pin % (pcs->width /
> >>> pcs->bits_per_pin) *
> >>> +                                   pcs->bits_per_pin;
> 
> >> Sounds like playing around pretty well defined macro and functions,
> >> e.g. DIV_ROUND_UP(), round_up().
> 
> > I admit, I just copied existing code (which may be a reason to leave this
> > the
> > way it is).
> 
> Ah, fair enough.
> 
> >  But, I only see once place to do this:
> >
> >         offset = round_down(byte_num, mux_bytes);
> >
> > Did I miss another?
> 
> I meant that you may use macros to make code cleaner. Though, taking
> above into consideration, it would be done as a separate patch later.

Yeah makes sense to me to do them separately. It would be good to
get Haojian's ack or tested-by on this one, I don't think I have
hardware where I can test the GPIO features with this driver.

Regards,

Tony