Re: [PATCH v2 5/8] pinctrl: add pinctrl driver for Rockchip SoCs

From: Heiko Stübner
Date: Fri Jun 07 2013 - 19:53:31 EST


Am Samstag, 8. Juni 2013, 01:13:48 schrieb Heiko Stübner:
> Am Freitag, 7. Juni 2013, 14:53:51 schrieb Linus Walleij:
> > On Thu, Jun 6, 2013 at 9:11 PM, Heiko Stübner <heiko@xxxxxxxxx> wrote:
> > > + for (i = 0, j = 0; i < size; i += 4, j++) {
> > > + unsigned long pinconf;
> > > +
> > > + num = be32_to_cpu(*list++);
> > > + bank = bank_num_to_bank(info, num);
> > > + if (IS_ERR(bank))
> > > + return PTR_ERR(bank);
> > > +
> > > + pin = be32_to_cpu(*list++);
> > > + grp->pins[j] = bank->pin_base + pin;
> > > + grp->func[j] = be32_to_cpu(*list++);
> > > +
> > > + pinconf = be32_to_cpu(*list++);
> > > + switch(pinconf) {
> > > + case RK_PINCTRL_NONE:
> > > + bias = PIN_CONFIG_BIAS_DISABLE;
> > > + break;
> > > + case RK_PINCTRL_PULL_PIN_DEFAULT:
> > > + bias = PIN_CONFIG_BIAS_PULL_PIN_DEFAULT;
> > > + break;
> > > + case RK_PINCTRL_PULL_UP:
> > > + bias = PIN_CONFIG_BIAS_PULL_UP;
> > > + break;
> > > + case RK_PINCTRL_PULL_DOWN:
> > > + bias = PIN_CONFIG_BIAS_PULL_DOWN;
> > > + break;
> > > + }
> > > +
> > > + grp->configs[j] = pinconf_to_config_packed(bias, 0);
> > > + }
> >
> > I would like this to be added to
> > drivers/pinctrl/pinconf-generic.c
> > as a utility function, with the header in
> > drivers/pinctrl/pinconf.h
> >
> > Also in a separate patch.
> >
> > > +++ b/include/dt-bindings/pinctrl/rockchip.h
> >
> > (...)
> >
> > > +#define RK_PINCTRL_NONE 0
> > > +#define RK_PINCTRL_PULL_PIN_DEFAULT (1 << 0)
> > > +#define RK_PINCTRL_PULL_UP (1 << 1)
> > > +#define RK_PINCTRL_PULL_DOWN (1 << 2)
> >
> > So I'd like these moved to /include/dt-bindings/pinctrl/pinconfig.h
> > and used as a separete include. Drop the RK_* prefix as it
> > will be universal and use a PINCONFIG_* prefix instead
> > of PINCTRL_*.
> >
> > I think that is the route we need to take.
> >
> > Bonus if you implement more config options from
> > pinconf-generic.h but otherwise me and others will have
> > to do it.
>
> Gah, damn me for always wanting to get bonus points ;-),
>
> I did play around a bit with the idea you described above and came up
> with the stuff a bit below. This is in no way meant to be finished, I
> also only was able to compile test it yet, but it looks like it might
> work when I test it tomorrow.
>
> So if possible I would just like to get a "looks halfway sane, continue"
> or "completely wrong track" please :-) :
>
>
> constants in dt-bindings/pinctrl/pinconfig.h:
> -----------------------------
> #define PINCONFIG_NONE 0
> #define PINCONFIG_BIAS_DISABLE (1 << 0)
> #define PINCONFIG_BIAS_HIGH_IMPEDANCE (1 << 1)
> #define PINCONFIG_BIAS_BUS_HOLD (1 << 2)
> #define PINCONFIG_BIAS_PULL_PIN_DEFAULT (1 << 3)
> #define PINCONFIG_BIAS_PULL_UP (1 << 4)
> #define PINCONFIG_BIAS_PULL_DOWN (1 << 5)
> #define PINCONFIG_DRIVE_PUSH_PULL (1 << 6)
> #define PINCONFIG_DRIVE_OPEN_DRAIN (1 << 7)
> #define PINCONFIG_DRIVE_OPEN_SOURCE (1 << 8)
> #define PINCONFIG_INPUT_SCHMITT_ENABLE (1 << 9)
> #define PINCONFIG_INPUT_SCHMITT_DISABLE (1 << 10)
> #define PINCONFIG_LOW_POWER_MODE (1 << 11)
> #define PINCONFIG_OUTPUT_LOW (1 << 12)
> #define PINCONFIG_OUTPUT_HIGH (1 << 13)
>
>
> and code including how the rockchip driver could look like:
> ---------
> diff --git a/drivers/pinctrl/pinconf-generic.c
> b/drivers/pinctrl/pinconf-generic.c index 9a6812b..35c40be 100644
> --- a/drivers/pinctrl/pinconf-generic.c
> +++ b/drivers/pinctrl/pinconf-generic.c
> @@ -139,3 +139,61 @@ void pinconf_generic_dump_config(struct pinctrl_dev
> *pctldev, }
> EXPORT_SYMBOL_GPL(pinconf_generic_dump_config);
> #endif
> +
> +/*
> + * Maps the devicetree config bits to actual pinconf values.
> + * The array indizes match the bits set in dt-bindings/pinctrl/pinconf.h
> + * and the array should contain an entry for each bit defined there
> + */
> +static unsigned long conf_map[] = {
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_DISABLE, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_BUS_HOLD, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_PULL_UP, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_BIAS_PULL_DOWN, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_DRIVE_PUSH_PULL, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_DRIVE_OPEN_DRAIN, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_DRIVE_OPEN_SOURCE, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1),
> + PIN_CONF_PACKED(PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_LOW_POWER_MODE, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_OUTPUT, 0),
> + PIN_CONF_PACKED(PIN_CONFIG_OUTPUT, 1),
> +};
> +
> +/*
> + * Parse a pinconf bitmap from a devicetree entry into individual pin
> configs. + * @pinconf: the bitmap containing config bits
> + * @configs: after the function returns contains a pointer to an array of
> + * pin configs
> + * @nconfigs: number of entries of configs
> + */
> +int pinconf_generic_parse_dt_bitmap(unsigned long pinconf,
> + unsigned long *configs,
> + unsigned int *nconfigs)
> +{
> + int bit;
> + int i;
> +
> + *nconfigs = hweight_long(pinconf);
> + configs = kzalloc(*nconfigs * sizeof(unsigned long), GFP_KERNEL);
> +
> + i = 0;
> + while (pinconf && i < *nconfigs) {
> + bit = __ffs(pinconf);
> + pinconf &= ~BIT(i);
> +
> + if (bit > ARRAY_SIZE(conf_map)) {
> + pr_err("%s: unknown bit %d\n", __func__, bit);
> + kfree(configs);
> + return -EINVAL;
> + }
> +
> + configs[i] = conf_map[bit];
> +
> + i++;
> + }
> +
> + return 0;
> +}
> diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h
> index 92c7267..0fab53a 100644
> --- a/drivers/pinctrl/pinconf.h
> +++ b/drivers/pinctrl/pinconf.h
> @@ -123,3 +123,9 @@ static inline void pinconf_generic_dump_config(struct
> pinctrl_dev *pctldev, return;
> }
> #endif
> +
> +#ifdef CONFIG_GENERIC_PINCONF
> +int pinconf_generic_parse_dt_bitmap(unsigned long pinconf,
> + unsigned long *configs,
> + unsigned int *nconfigs);
> +#endif
> diff --git a/drivers/pinctrl/pinctrl-rockchip.c
> b/drivers/pinctrl/pinctrl-rockchip.c index b77e241..88398df 100644
> --- a/drivers/pinctrl/pinctrl-rockchip.c
> +++ b/drivers/pinctrl/pinctrl-rockchip.c
> @@ -40,6 +40,7 @@
> #include <dt-bindings/pinctrl/rockchip.h>
>
> #include "core.h"
> +#include "pinconf.h"
>
> /* GPIO control registers */
> #define GPIO_SWPORT_DR 0x00
> @@ -639,7 +640,8 @@ static int rockchip_pinctrl_parse_groups(struct
> device_node *np, int num;
> int i, j;
> int pin;
> - int bias;
> + int ret;
> + int nconfigs;
>
> dev_dbg(info->dev, "group(%d): %s\n", index, np->name);
>
> @@ -683,22 +685,16 @@ static int rockchip_pinctrl_parse_groups(struct
> device_node *np, grp->func[j] = be32_to_cpu(*list++);
>
> pinconf = be32_to_cpu(*list++);
> - switch(pinconf) {
> - case RK_PINCTRL_NONE:
> - bias = PIN_CONFIG_BIAS_DISABLE;
> - break;
> - case RK_PINCTRL_PULL_PIN_DEFAULT:
> - bias = PIN_CONFIG_BIAS_PULL_PIN_DEFAULT;
> - break;
> - case RK_PINCTRL_PULL_UP:
> - bias = PIN_CONFIG_BIAS_PULL_UP;
> - break;
> - case RK_PINCTRL_PULL_DOWN:
> - bias = PIN_CONFIG_BIAS_PULL_DOWN;
> - break;
> - }
>
> - grp->configs[j] = pinconf_to_config_packed(bias, 0);
> + ret = pinconf_generic_parse_dt_bitmap(pinconf,
> + &grp->configs[j], &nconfigs);

of course this part is obviously wrong, which I just realized, because the
configs array only contains usigned longs

it must be more like
pinconf_generic_parse_dt_bitmap(pinconf, configs, &nconfigs)
...
grp->configs[j] = configs[0];

or better yet simply carrying the created configs without copying entries or
limiting the number of configs


> + if (ret)
> + return ret;
> +
> + if (nconfigs != 1) {
> + pr_err("unexpected number of config entries\n");
> + return -EINVAL;
> + }
> }
>
> return 0;

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