Hi Prabhakar,
On Thu, Sep 30, 2021 at 2:17 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote:
> Add support to get/set drive-strength and output-impedance of the pins.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> @@ -47,6 +47,7 @@
> #define PIN_CFG_FILONOFF BIT(9)
> #define PIN_CFG_FILNUM BIT(10)
> #define PIN_CFG_FILCLKSEL BIT(11)
> +#define PIN_CFG_GROUP_B BIT(12)
Perhaps it would be easier to have separate PIN_CFG_IOLH_A and
PIN_CFG_IOLH_B flags, instead of a PIN_CFG_IOLH flag and a
PIN_CFG_GROUP_B modifier flag?
>
> #define RZG2L_MPXED_PIN_FUNCS (PIN_CFG_IOLH | \
> PIN_CFG_SR | \
> @@ -484,6 +513,38 @@ static int rzg2l_pinctrl_pinconf_get(struct pinctrl_dev *pctldev,
> break;
> }
>
> + case PIN_CONFIG_OUTPUT_IMPEDANCE:
> + case PIN_CONFIG_DRIVE_STRENGTH: {
> + unsigned int mA[4] = { 2, 4, 8, 12 };
> + unsigned int oi[4] = { 100, 66, 50, 33 };
static const
> +
> + if (param == PIN_CONFIG_DRIVE_STRENGTH) {
> + if (!(cfg & PIN_CFG_IOLH) || groupb_pin)
> + return -EINVAL;
> + } else {
> + if (!(cfg & PIN_CFG_IOLH) || !groupb_pin)
> + return -EINVAL;
> + }
> +
> + spin_lock_irqsave(&pctrl->lock, flags);
> +
> + /* handle _L/_H for 32-bit register read/write */
> + addr = pctrl->base + IOLH(port);
> + if (bit >= 4) {
> + bit -= 4;
> + addr += 4;
> + }
> +
> + reg = readl(addr) & (IOLH_MASK << (bit * 8));
> + reg = reg >> (bit * 8);
> + if (param == PIN_CONFIG_DRIVE_STRENGTH)
> + arg = mA[reg];
> + else
> + arg = oi[reg];
> + spin_unlock_irqrestore(&pctrl->lock, flags);
I think you've reached the point where it starts to make sense to
have helper functions to read and modify these sub-register fields
that may be located into the current or next register.
And after that, you can split it in two smaller separate cases for
drive strength and output impedance.
> + break;
> + }
> +
> default:
> return -ENOTSUPP;
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
