[PATCH] pinctrl: msm: Add check for pinctrl group is valid

[PATCH] pinctrl: msm: Add check for pinctrl group is valid

[Mayank Grover]

The list of reserved gpio pins for platform are populated
in gpiochip valid_mask.

Here on MSM common driver introduce ability to check if
pingroup is valid, by parsing pins in pingroup against
reserved pins for gpios. This does not handle non-gpio
pingroups.

Signed-off-by: Mayank Grover <groverm@codeaurora.org>
---
 drivers/pinctrl/qcom/pinctrl-msm.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index 85858c1..b6ebe26 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -261,6 +261,24 @@ static unsigned msm_regval_to_drive(u32 val)
 	return (val + 1) * 2;
 }
 
+static bool msm_pingroup_is_valid(struct msm_pinctrl *pctrl,
+				  const struct msm_pingroup *g)
+{
+	const unsigned int *pins = g->pins;
+	unsigned int num_pins = g->npins;
+	struct gpio_chip *chip = &pctrl->chip;
+	unsigned int max_gpios = chip->ngpio;
+	unsigned int i;
+
+	for (i = 0; i < num_pins; i++) {
+		/* Doesn't handle non-gpio pingroups */
+		if (pins[i] < max_gpios &&
+		    !gpiochip_line_is_valid(chip, pins[i]))
+			return false;
+	}
+	return true;
+}
+
 static int msm_config_group_get(struct pinctrl_dev *pctldev,
 				unsigned int group,
 				unsigned long *config)
@@ -276,6 +294,10 @@ static int msm_config_group_get(struct pinctrl_dev *pctldev,
 
 	g = &pctrl->soc->groups[group];
 
+	/* Check if group has all valid pins */
+	if (!msm_pingroup_is_valid(pctrl, g))
+		return -EINVAL;
+
 	ret = msm_config_reg(pctrl, g, param, &mask, &bit);
 	if (ret < 0)
 		return ret;
@@ -355,6 +377,10 @@ static int msm_config_group_set(struct pinctrl_dev *pctldev,
 
 	g = &pctrl->soc->groups[group];
 
+	/* Check if group has all valid pins */
+	if (!msm_pingroup_is_valid(pctrl, g))
+		return -EINVAL;
+
 	for (i = 0; i < num_configs; i++) {
 		param = pinconf_to_config_param(configs[i]);
 		arg = pinconf_to_config_argument(configs[i]);
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member of the Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH] pinctrl: msm: Add check for pinctrl group is valid

[Bjorn Andersson]

On Mon 18 May 08:50 PDT 2020, Mayank Grover wrote:

> The list of reserved gpio pins for platform are populated
> in gpiochip valid_mask.
> 
> Here on MSM common driver introduce ability to check if
> pingroup is valid, by parsing pins in pingroup against
> reserved pins for gpios. This does not handle non-gpio
> pingroups.
> 

Thanks Mayank, I can confirm that this is a problem, but don't we need
this on some of the pinmux_ops as well?

@Linus, we started off with something similar for GPIOs and ended up
with the logic in the core code. Should we somehow try to do the same
for pinctrl?

Regards,
Bjorn

> Signed-off-by: Mayank Grover <groverm@codeaurora.org>
> ---
>  drivers/pinctrl/qcom/pinctrl-msm.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
> index 85858c1..b6ebe26 100644
> --- a/drivers/pinctrl/qcom/pinctrl-msm.c
> +++ b/drivers/pinctrl/qcom/pinctrl-msm.c
> @@ -261,6 +261,24 @@ static unsigned msm_regval_to_drive(u32 val)
>  	return (val + 1) * 2;
>  }
>  
> +static bool msm_pingroup_is_valid(struct msm_pinctrl *pctrl,
> +				  const struct msm_pingroup *g)
> +{
> +	const unsigned int *pins = g->pins;
> +	unsigned int num_pins = g->npins;
> +	struct gpio_chip *chip = &pctrl->chip;
> +	unsigned int max_gpios = chip->ngpio;
> +	unsigned int i;
> +
> +	for (i = 0; i < num_pins; i++) {
> +		/* Doesn't handle non-gpio pingroups */
> +		if (pins[i] < max_gpios &&
> +		    !gpiochip_line_is_valid(chip, pins[i]))
> +			return false;
> +	}
> +	return true;
> +}
> +
>  static int msm_config_group_get(struct pinctrl_dev *pctldev,
>  				unsigned int group,
>  				unsigned long *config)
> @@ -276,6 +294,10 @@ static int msm_config_group_get(struct pinctrl_dev *pctldev,
>  
>  	g = &pctrl->soc->groups[group];
>  
> +	/* Check if group has all valid pins */
> +	if (!msm_pingroup_is_valid(pctrl, g))
> +		return -EINVAL;
> +
>  	ret = msm_config_reg(pctrl, g, param, &mask, &bit);
>  	if (ret < 0)
>  		return ret;
> @@ -355,6 +377,10 @@ static int msm_config_group_set(struct pinctrl_dev *pctldev,
>  
>  	g = &pctrl->soc->groups[group];
>  
> +	/* Check if group has all valid pins */
> +	if (!msm_pingroup_is_valid(pctrl, g))
> +		return -EINVAL;
> +
>  	for (i = 0; i < num_configs; i++) {
>  		param = pinconf_to_config_param(configs[i]);
>  		arg = pinconf_to_config_argument(configs[i]);
> -- 
> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
> member of the Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH] pinctrl: msm: Add check for pinctrl group is valid

[Mayank Grover]

O Mon, May 18, 2020 at 06:38:13PM -0700, Bjorn Andersson wrote:
> On Mon 18 May 08:50 PDT 2020, Mayank Grover wrote:
> 
> > The list of reserved gpio pins for platform are populated
> > in gpiochip valid_mask.
> > 
> > Here on MSM common driver introduce ability to check if
> > pingroup is valid, by parsing pins in pingroup against
> > reserved pins for gpios. This does not handle non-gpio
> > pingroups.
> > 
> 
> Thanks Mayank, I can confirm that this is a problem, but don't we need
> this on some of the pinmux_ops as well?
>

Thanks Bjorn, for quick reply.

For pinmux ops, we already have check for validity in msm_pinmux_request
function hook.

request is getting called by core to check availabity of pin before acquiring
the pin.

Hence, I think we don't need this check there.

Regards,
Mayank

 
> @Linus, we started off with something similar for GPIOs and ended up
> with the logic in the core code. Should we somehow try to do the same
> for pinctrl?
> 
> Regards,
> Bjorn
> 
> > Signed-off-by: Mayank Grover <groverm@codeaurora.org>
> > ---
> >  drivers/pinctrl/qcom/pinctrl-msm.c | 26 ++++++++++++++++++++++++++
> >  1 file changed, 26 insertions(+)
> > 
> > diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
> > index 85858c1..b6ebe26 100644
> > --- a/drivers/pinctrl/qcom/pinctrl-msm.c
> > +++ b/drivers/pinctrl/qcom/pinctrl-msm.c
> > @@ -261,6 +261,24 @@ static unsigned msm_regval_to_drive(u32 val)
> >  	return (val + 1) * 2;
> >  }
> >  
> > +static bool msm_pingroup_is_valid(struct msm_pinctrl *pctrl,
> > +				  const struct msm_pingroup *g)
> > +{
> > +	const unsigned int *pins = g->pins;
> > +	unsigned int num_pins = g->npins;
> > +	struct gpio_chip *chip = &pctrl->chip;
> > +	unsigned int max_gpios = chip->ngpio;
> > +	unsigned int i;
> > +
> > +	for (i = 0; i < num_pins; i++) {
> > +		/* Doesn't handle non-gpio pingroups */
> > +		if (pins[i] < max_gpios &&
> > +		    !gpiochip_line_is_valid(chip, pins[i]))
> > +			return false;
> > +	}
> > +	return true;
> > +}
> > +
> >  static int msm_config_group_get(struct pinctrl_dev *pctldev,
> >  				unsigned int group,
> >  				unsigned long *config)
> > @@ -276,6 +294,10 @@ static int msm_config_group_get(struct pinctrl_dev *pctldev,
> >  
> >  	g = &pctrl->soc->groups[group];
> >  
> > +	/* Check if group has all valid pins */
> > +	if (!msm_pingroup_is_valid(pctrl, g))
> > +		return -EINVAL;
> > +
> >  	ret = msm_config_reg(pctrl, g, param, &mask, &bit);
> >  	if (ret < 0)
> >  		return ret;
> > @@ -355,6 +377,10 @@ static int msm_config_group_set(struct pinctrl_dev *pctldev,
> >  
> >  	g = &pctrl->soc->groups[group];
> >  
> > +	/* Check if group has all valid pins */
> > +	if (!msm_pingroup_is_valid(pctrl, g))
> > +		return -EINVAL;
> > +
> >  	for (i = 0; i < num_configs; i++) {
> >  		param = pinconf_to_config_param(configs[i]);
> >  		arg = pinconf_to_config_argument(configs[i]);
> > -- 
> > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
> > member of the Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH] pinctrl: msm: Add check for pinctrl group is valid

[Linus Walleij]

On Tue, May 19, 2020 at 3:39 AM Bjorn Andersson
<bjorn.andersson@linaro.org> wrote:

> @Linus, we started off with something similar for GPIOs and ended up
> with the logic in the core code. Should we somehow try to do the same
> for pinctrl?

msm_pingroup_is_valid() looks very reusable but I'm afraid I do not
understand the implicit assumptions around it, but I guess yes,
if it can be properly documented etc.

Yours,
Linus Walleij

Re: [PATCH] pinctrl: msm: Add check for pinctrl group is valid

[Mayank Grover]

On Mon, May 25, 2020 at 11:02:14AM +0200, Linus Walleij wrote:
> On Tue, May 19, 2020 at 3:39 AM Bjorn Andersson
> <bjorn.andersson@linaro.org> wrote:
> 
> > @Linus, we started off with something similar for GPIOs and ended up
> > with the logic in the core code. Should we somehow try to do the same
> > for pinctrl?
> 
> msm_pingroup_is_valid() looks very reusable but I'm afraid I do not
> understand the implicit assumptions around it, but I guess yes,
> if it can be properly documented etc.
> 
> Yours,
> Linus Walleij

Hi Bjorn,

Can you please help guide further on this ?
we can validate group using request calls similar to pinmux_ops here.

-Mayank