by Lad, Prabhakar

[permalink] [raw]

Subject: Re: [PATCH v2 10/13] pinctrl: renesas: pinctrl-rzg2l: Add support to set pulling up/down the pins

On Thu, May 30, 2024 at 8:48 AM claudiu beznea <[email protected]> wrote:
>
> Hi, Prabhakar,
>
> On 23.04.2024 20:58, Prabhakar wrote:
> > From: Lad Prabhakar <[email protected]>
> >
> > Add support to configure bias-disable, bias-pull-up and bias-pull-down
> > properties of the pin.
> >
> > Two new function pointers get_bias_param() and get_bias_val() are
> > introduced as the values in PUPD register differ when compared to
> > RZ/G2L family and RZ/V2H(P) SoC,
> >
> > Value | RZ/G2L | RZ/V2H
> > ---------------------------------
> > 00b: | Bias Disabled | Pull up/down disabled
> > 01b: | Pull-up | Pull up/down disabled
> > 10b: | Pull-down | Pull-down
> > 11b: | Prohibited | Pull-up
> >
> > Signed-off-by: Lad Prabhakar <[email protected]>
> > ---
> > RFC->v2
> > - New patch
> > ---
> > drivers/pinctrl/renesas/pinctrl-rzg2l.c | 73 +++++++++++++++++++++++++
> > 1 file changed, 73 insertions(+)
> >
> > diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > index 102fa75c71d3..c144bf43522b 100644
> > --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > @@ -122,6 +122,7 @@
> > #define IOLH(off) (0x1000 + (off) * 8)
> > #define SR(off) (0x1400 + (off) * 8)
> > #define IEN(off) (0x1800 + (off) * 8)
> > +#define PUPD(off) (0x1C00 + (off) * 8)
> > #define ISEL(off) (0x2C00 + (off) * 8)
> > #define SD_CH(off, ch) ((off) + (ch) * 4)
> > #define ETH_POC(off, ch) ((off) + (ch) * 4)
> > @@ -140,6 +141,7 @@
> > #define IEN_MASK 0x01
> > #define IOLH_MASK 0x03
> > #define SR_MASK 0x01
> > +#define PUPD_MASK 0x03
> >
> > #define PM_INPUT 0x1
> > #define PM_OUTPUT 0x2
> > @@ -265,6 +267,8 @@ struct rzg2l_pinctrl_data {
> > void (*pmc_writeb)(struct rzg2l_pinctrl *pctrl, u8 val, void __iomem *addr);
> > u32 (*read_oen)(struct rzg2l_pinctrl *pctrl, u32 caps, u32 offset, u8 pin);
> > int (*write_oen)(struct rzg2l_pinctrl *pctrl, u32 caps, u32 offset, u8 pin, u8 oen);
> > + int (*get_bias_param)(u8 val);
> > + int (*get_bias_val)(enum pin_config_param param);
> > };
> >
> > /**
> > @@ -1081,6 +1085,38 @@ static int rzg2l_write_oen(struct rzg2l_pinctrl *pctrl, u32 caps, u32 offset, u8
> > return 0;
> > }
> >
> > +static int rzg2l_get_bias_param(u8 val)
> > +{
> > + switch (val) {
> > + case 0:
> > + return PIN_CONFIG_BIAS_DISABLE;
> > + case 1:
> > + return PIN_CONFIG_BIAS_PULL_UP;
> > + case 2:
> > + return PIN_CONFIG_BIAS_PULL_DOWN;
> > + default:
> > + break;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static int rzg2l_get_bias_val(enum pin_config_param param)
> > +{
> > + switch (param) {
> > + case PIN_CONFIG_BIAS_DISABLE:
> > + return 0;
> > + case PIN_CONFIG_BIAS_PULL_UP:
> > + return 1;
> > + case PIN_CONFIG_BIAS_PULL_DOWN:
> > + return 2;
> > + default:
> > + break;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > static int rzg2l_pinctrl_pinconf_get(struct pinctrl_dev *pctldev,
> > unsigned int _pin,
> > unsigned long *config)
> > @@ -1139,6 +1175,25 @@ static int rzg2l_pinctrl_pinconf_get(struct pinctrl_dev *pctldev,
> > arg = rzg2l_read_pin_config(pctrl, SR(off), bit, SR_MASK);
> > break;
> >
> > + case PIN_CONFIG_BIAS_DISABLE:
> > + case PIN_CONFIG_BIAS_PULL_UP:
> > + case PIN_CONFIG_BIAS_PULL_DOWN: {
>
> Block { } can be removed here.
>
> > + if (!(cfg & PIN_CFG_PUPD))
> > + return -EINVAL;
> > +
> > + ret = pctrl->data->get_bias_param(rzg2l_read_pin_config(pctrl,
> > + PUPD(off),
> > + bit, PUPD_MASK));
> > + if (ret < 0)
> > + return ret;
> > +
> > + if (ret != param)
> > + return -EINVAL;
>
> Can this happen? Otherwise it can be removed.
>
Yes this can happen (and is needed) as we want to report only the
current BIAS setting of the pin.

For example without this condition I get the below for ET1_RXD3 pin:
pin 173 (ET1_RXD3): input bias disabled, input bias pull down (0x1
ohms), input bias pull up (0x1 ohms)
with the check included:
pin 173 (ET1_RXD3): input bias disabled

Cheers,
Prabhakar