Re: [PATCH 12/20] pinctrl: berlin: add optional pinconf support

[Richard GENOUD <richard.genoud@bootlin.com>]

Le 29/09/2026 à 08:14, Jisheng Zhang a écrit :
> Add pinconf support for newer Synaptics SoCs.
> 
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> ---
>   drivers/pinctrl/berlin/berlin.c | 232 +++++++++++++++++++++++++++++++-
>   1 file changed, 228 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pinctrl/berlin/berlin.c b/drivers/pinctrl/berlin/berlin.c
> index 0c2179b98629..06c67f00c527 100644
> --- a/drivers/pinctrl/berlin/berlin.c
> +++ b/drivers/pinctrl/berlin/berlin.c
> @@ -13,6 +13,8 @@
>   #include <linux/of.h>
>   #include <linux/of_address.h>
>   #include <linux/of_device.h>
> +#include <linux/pinctrl/pinconf-generic.h>
> +#include <linux/pinctrl/pinconf.h>
>   #include <linux/pinctrl/pinctrl.h>
>   #include <linux/pinctrl/pinmux.h>
>   #include <linux/platform_device.h>
> @@ -20,9 +22,24 @@
>   #include <linux/slab.h>
>   
>   #include "../core.h"
> +#include "../pinconf.h"
>   #include "../pinctrl-utils.h"
>   #include "berlin.h"
>   
> +#define PINCFG_DS_10BIT		GENMASK(3, 0)
> +#define PINCFG_IE_10BIT		BIT(4)
> +#define PINCFG_PE_10BIT		BIT(5)
> +#define PINCFG_PS_10BIT		BIT(6)
> +#define PINCFG_SL_10BIT		BIT(7)
> +#define PINCFG_SPU_10BIT	BIT(8)
> +#define PINCFG_ST_10BIT		BIT(9)
> +#define PINCFG_DS_8BIT		GENMASK(2, 0)
> +#define PINCFG_IE_8BIT		BIT(3)
> +#define PINCFG_PD_8BIT		BIT(4)
> +#define PINCFG_PU_8BIT		BIT(5)
> +#define PINCFG_SL_8BIT		BIT(6)
> +#define PINCFG_ST_8BIT		BIT(7)
> +
>   struct berlin_pinctrl {
>   	struct regmap *regmap;
>   	struct device *dev;
> @@ -56,6 +73,8 @@ static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
>   	struct property *prop;
>   	const char *function_name, *group_name;
>   	unsigned reserved_maps = 0;
> +	unsigned long *configs = NULL;
> +	unsigned int num_configs = 0;
>   	int ret, ngroups;
>   
>   	*map = NULL;
> @@ -75,11 +94,19 @@ static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
>   		return -EINVAL;
>   	}
>   
> +	ret = pinconf_generic_parse_dt_config(node, pctrl_dev, &configs,
> +					      &num_configs);
> +	if (ret < 0) {
> +		dev_err(pctrl->dev, "%s: could not parse node property\n",
> +			node->name);
> +		return ret;
> +	}
> +
>   	ret = pinctrl_utils_reserve_map(pctrl_dev, map, &reserved_maps,
> -					num_maps, ngroups);
> +					num_maps, ngroups * (num_configs + 1));
>   	if (ret) {
>   		dev_err(pctrl->dev, "can't reserve map: %d\n", ret);
> -		return ret;
> +		goto exit;
>   	}
>   
>   	of_property_for_each_string(node, "groups", prop, group_name) {
> @@ -88,11 +115,22 @@ static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
>   						function_name);
>   		if (ret) {
>   			dev_err(pctrl->dev, "can't add map: %d\n", ret);
> -			return ret;
> +			goto exit;
> +		}
> +
> +		if (num_configs) {
> +			ret = pinctrl_utils_add_map_configs(pctrl_dev, map,
> +					&reserved_maps, num_maps, group_name,
> +					configs, num_configs,
> +					PIN_MAP_TYPE_CONFIGS_GROUP);
> +			if (ret < 0)
> +				goto exit;
>   		}
>   	}
>   
> -	return 0;
> +exit:
> +	kfree(configs);
> +	return ret;
>   }
>   
>   static const struct pinctrl_ops berlin_pinctrl_ops = {
> @@ -177,6 +215,191 @@ static const struct pinmux_ops berlin_pinmux_ops = {
>   	.set_mux		= &berlin_pinmux_set,
>   };
>   
> +static int berlin_pinconf_group_get(struct pinctrl_dev *pctrl_dev,
> +				    unsigned int group, unsigned long *configs)
> +{
> +	enum pin_config_param param = pinconf_to_config_param(*configs);
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +	const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
> +	bool enabled;
> +	u32 val;
> +	int ret;
> +	u8 conf_bits = group_desc->conf_bits;
> +
> +	if (!conf_bits)
> +		return -EOPNOTSUPP;
> +
> +	ret = regmap_read(pctrl->regmap, group_desc->conf_offset, &val);
> +	if (ret)
> +		return ret;
> +
> +	switch (param) {
> +	case PIN_CONFIG_BIAS_DISABLE:
> +		if (conf_bits == 10)
> +			enabled = !(val & PINCFG_PE_10BIT);
> +		else
> +			enabled = !(val & (PINCFG_PD_8BIT | PINCFG_PU_8BIT));
> +		val = 0;
> +		break;
> +	case PIN_CONFIG_BIAS_PULL_DOWN:
> +		if (conf_bits == 10)
> +			enabled = (val & (PINCFG_PE_10BIT | PINCFG_PS_10BIT)) == PINCFG_PE_10BIT;
> +		else
> +			enabled = val & PINCFG_PD_8BIT;
> +		val = enabled ? 1 : 0;
> +		break;
> +	case PIN_CONFIG_BIAS_PULL_UP:
> +		if (conf_bits == 10) {
> +			if ((val & (PINCFG_PE_10BIT | PINCFG_PS_10BIT)) == (PINCFG_PE_10BIT | PINCFG_PS_10BIT)) {
> +				enabled = true;
> +				if (val & PINCFG_SPU_10BIT)
> +					val = 2;
> +				else
> +					val = 1;
> +			} else {
> +				enabled = false;
> +				val = 0;
> +			}
> +		} else {
> +			enabled = val & PINCFG_PU_8BIT;
> +			val = enabled ? 1 : 0;
> +		}
> +		break;
> +	case PIN_CONFIG_DRIVE_STRENGTH:
> +		enabled = true;
> +		if (conf_bits == 10)
> +			val = FIELD_GET(PINCFG_DS_10BIT, val);
> +		else
> +			val = FIELD_GET(PINCFG_DS_8BIT, val);
> +		break;
> +	case PIN_CONFIG_INPUT_ENABLE:
> +		if (conf_bits == 10)
> +			enabled = val & PINCFG_IE_10BIT;
> +		else
> +			enabled = val & PINCFG_IE_8BIT;
> +		val = enabled ? 1 : 0;
> +		break;
> +	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
> +		if (conf_bits == 10)
> +			enabled = val & PINCFG_ST_10BIT;
> +		else
> +			enabled = val & PINCFG_ST_8BIT;
> +		val = enabled ? 1 : 0;
> +		break;
> +	case PIN_CONFIG_SLEW_RATE:
> +		if (conf_bits == 10)
> +			enabled = val & PINCFG_SL_10BIT;
> +		else
> +			enabled = val & PINCFG_SL_8BIT;
> +		val = enabled ? 1 : 0;
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	*configs = pinconf_to_config_packed(param, val);
> +	return enabled ? 0 : -EINVAL;
> +}
> +
> +static int berlin_pinconf_group_set(struct pinctrl_dev *pctrl_dev,
> +				    unsigned int group, unsigned long *configs,
> +				    unsigned int nconfigs)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +	const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
> +	u8 conf_bits = group_desc->conf_bits;
> +	u32 mask = 0, val = 0;
> +	int i;
> +
> +	if (!conf_bits)
> +		return -EOPNOTSUPP;
> +
> +	for (i = 0; i < nconfigs; i++) {
> +		enum pin_config_param param =
> +					pinconf_to_config_param(configs[i]);
> +		u32 arg = pinconf_to_config_argument(configs[i]);
> +
> +		switch (param) {
> +		case PIN_CONFIG_BIAS_DISABLE:
> +			if (conf_bits == 10)
> +				mask |= (PINCFG_PE_10BIT | PINCFG_PS_10BIT | PINCFG_SPU_10BIT);
> +			else
> +				mask |= (PINCFG_PU_8BIT | PINCFG_PD_8BIT);
> +			break;
> +		case PIN_CONFIG_BIAS_PULL_DOWN:
> +			if (conf_bits == 10) {
> +				mask |= (PINCFG_PE_10BIT | PINCFG_PS_10BIT | PINCFG_SPU_10BIT);
> +				val |= PINCFG_PE_10BIT;
> +			} else {
> +				mask |= (PINCFG_PU_8BIT | PINCFG_PD_8BIT);
> +				val |= PINCFG_PD_8BIT;
> +			}
> +			break;
> +		case PIN_CONFIG_BIAS_PULL_UP:
> +			if (conf_bits == 10) {
> +				mask |= (PINCFG_PE_10BIT | PINCFG_PS_10BIT | PINCFG_SPU_10BIT);
> +				val |= (PINCFG_PE_10BIT | PINCFG_PS_10BIT);
> +				if (arg == 2)
> +					val |= PINCFG_SPU_10BIT;
The value 2 Ohms is hijacked to be used as strong pull up.
The more I look at that, the more it feels hacky.

> +			} else {
> +				mask |= (PINCFG_PU_8BIT | PINCFG_PD_8BIT);
> +				val |= PINCFG_PU_8BIT;
> +			}
> +			break;
> +		case PIN_CONFIG_DRIVE_STRENGTH:
> +			if (conf_bits == 10)
> +				mask |= PINCFG_DS_10BIT;
> +			else
> +				mask |= PINCFG_DS_8BIT;
> +			val |= arg;
The drive strength is assumed to be lsb (which is the case), but maybe 
something like:
	if (arg > FIELD_MAX(mask))
		return -EINVAL;
	val |= FIELD_PREP(mask, arg);
would be more generic.

> +			break;
> +		case PIN_CONFIG_INPUT_ENABLE:
> +			if (conf_bits == 10) {
> +				mask |= PINCFG_IE_10BIT;
> +				if (arg)
> +					val |= PINCFG_IE_10BIT;
> +			} else {
> +				mask |= PINCFG_IE_8BIT;
> +				if (arg)
> +					val |= PINCFG_IE_8BIT;
> +			}
> +			break;
> +		case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
> +			if (conf_bits == 10) {
> +				mask |= PINCFG_ST_10BIT;
> +				if (arg)
> +					val |= PINCFG_ST_10BIT;
> +			} else {
> +				mask |= PINCFG_ST_8BIT;
> +				if (arg)
> +					val |= PINCFG_ST_8BIT;
> +			}
> +			break;
> +		case PIN_CONFIG_SLEW_RATE:
> +			if (conf_bits == 10) {
> +				mask |= PINCFG_SL_10BIT;
> +				if (arg)
> +					val |= PINCFG_SL_10BIT;
> +			} else {
> +				mask |= PINCFG_SL_8BIT;
> +				if (arg)
> +					val |= PINCFG_SL_8BIT;
> +			}
> +			break;
> +		default:
> +			return -EOPNOTSUPP;
> +		}
> +	}
> +
> +	return regmap_update_bits(pctrl->regmap, group_desc->conf_offset, mask, val);
> +}
> +
> +static const struct pinconf_ops berlin_confops = {
> +	.is_generic = true,
> +	.pin_config_group_get = berlin_pinconf_group_get,
> +	.pin_config_group_set = berlin_pinconf_group_set,
> +};
> +
>   static int berlin_pinctrl_add_function(struct berlin_pinctrl *pctrl,
>   				       const char *name)
>   {
> @@ -287,6 +510,7 @@ static const struct pinctrl_desc berlin_pctrl_desc = {
>   	.name		= "berlin-pinctrl",
>   	.pctlops	= &berlin_pinctrl_ops,
>   	.pmxops		= &berlin_pinmux_ops,
> +	.confops	= &berlin_confops,
>   	.owner		= THIS_MODULE,
>   };
>   
Regards,
Richard