On Thu 26 Dec 2024 at 15:57, Xianwei Zhao via B4 Relay <devnull+xianwei.zhao.amlogic.com@xxxxxxxxxx> wrote:
> From: Xianwei Zhao <xianwei.zhao@xxxxxxxxxxx>
>
> When describing pin mux func through pinmux propertity,
> a standard API is added for support. The pinmux contains pin
> identification and mux values, which can include multiple
> pins. And groups configuration use other word. DTS such as:
>
> func-name {
> group_alias: group-name{
> pinmux= <pin_id << 8 | mux_value)>,
> <pin_id << 8 | mux_value)>;
This representation does not seem very generic but more tailored to
your use-case.
> bias-pull-up;
> drive-strength-microamp = <4000>;
If you want to add pinmux (aka alternate function) selection as a
pinconf prop then I think there should be a single pinmux setting per
group, and as many groups as you need per function defined.
something like
func-foo {
group-a {
groups = "pin_a", "pin_b";
bias-pull-up;
alternate-function = <2>;
};
group-b {
groups = "pin_c"";
bias-disable;
alternate-function = <5>;
};
};
Something similar is already done to handle different pin bias requirement
on single function on amlogic platforms:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/amlogic/meson-axg.dtsi?h=v6.13-rc6#n421
> };
> };
>
> Signed-off-by: Xianwei Zhao <xianwei.zhao@xxxxxxxxxxx>
> ---
> drivers/pinctrl/pinconf-generic.c | 130 ++++++++++++++++++++++++++++++++
> drivers/pinctrl/pinconf.h | 4 +
> include/linux/pinctrl/pinconf-generic.h | 4 +
> 3 files changed, 138 insertions(+)
>
> diff --git a/drivers/pinctrl/pinconf-generic.c b/drivers/pinctrl/pinconf-generic.c
> index 0b13d7f17b32..a4d3c12a80c4 100644
> --- a/drivers/pinctrl/pinconf-generic.c
> +++ b/drivers/pinctrl/pinconf-generic.c
> @@ -233,6 +233,67 @@ static void parse_dt_cfg(struct device_node *np,
> }
> }
>
> +/**
> + * pinconf_generic_parse_dt_pinmux()
> + * parse the pinmux properties into generic pin mux values.
> + * @np: node containing the pinmux properties
> + * @pctldev: pincontrol device
> + * @pid: array with pin identity entries
> + * @pmux: array with pin mux value entries
> + * @npins: number of pins
> + *
> + * pinmux propertity: mux value [0,7]bits and pin identity [8,31]bits.
> + */
> +int pinconf_generic_parse_dt_pinmux(struct device_node *np, struct device *dev,
> + unsigned int **pid, unsigned int **pmux,
> + unsigned int *npins)
> +{
> + unsigned int *pid_t;
> + unsigned int *pmux_t;
> + struct property *prop;
> + unsigned int npins_t, i;
> + u32 value;
> + int ret;
> +
> + prop = of_find_property(np, "pinmux", NULL);
> + if (!prop) {
> + dev_info(dev, "Missing pinmux property\n");
> + return -ENOENT;
> + }
> +
> + if (!pid || !pmux || !npins) {
> + dev_err(dev, "paramers error\n");
> + return -EINVAL;
> + }
> +
> + npins_t = prop->length / sizeof(u32);
> + pid_t = devm_kcalloc(dev, npins_t, sizeof(*pid_t), GFP_KERNEL);
> + pmux_t = devm_kcalloc(dev, npins_t, sizeof(*pmux_t), GFP_KERNEL);
> + if (!pid_t || !pmux_t) {
> + dev_err(dev, "kalloc memory fail\n");
> + return -ENOMEM;
> + }
> + for (i = 0; i < npins_t; i++) {
> + ret = of_property_read_u32_index(np, "pinmux", i, &value);
> + if (ret) {
> + dev_err(dev, "get pinmux value fail\n");
> + goto exit;
> + }
> + pmux_t[i] = value & 0xff;
> + pid_t[i] = (value >> 8) & 0xffffff;
> + }
> + *pid = pid_t;
> + *pmux = pmux_t;
> + *npins = npins_t;
> +
> + return 0;
> +exit:
> + devm_kfree(dev, pid_t);
> + devm_kfree(dev, pmux_t);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(pinconf_generic_parse_dt_pinmux);
> +
> /**
> * pinconf_generic_parse_dt_config()
> * parse the config properties into generic pinconfig values.
> @@ -295,6 +356,75 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
> }
> EXPORT_SYMBOL_GPL(pinconf_generic_parse_dt_config);
>
> +int pinconf_generic_dt_node_to_map_pinmux(struct pinctrl_dev *pctldev,
> + struct device_node *np,
> + struct pinctrl_map **map,
> + unsigned int *num_maps)
> +{
> + struct device *dev = pctldev->dev;
> + struct device_node *pnode;
> + unsigned long *configs = NULL;
> + unsigned int num_configs = 0;
> + struct property *prop;
> + unsigned int reserved_maps;
> + int reserve;
> + int ret;
> +
> + prop = of_find_property(np, "pinmux", NULL);
> + if (!prop) {
> + dev_info(dev, "Missing pinmux property\n");
> + return -ENOENT;
> + }
> +
> + pnode = of_get_parent(np);
> + if (!pnode) {
> + dev_info(dev, "Missing function node\n");
> + return -EINVAL;
> + }
> +
> + reserved_maps = 0;
> + *map = NULL;
> + *num_maps = 0;
> +
> + ret = pinconf_generic_parse_dt_config(np, pctldev, &configs,
> + &num_configs);
> + if (ret < 0) {
> + dev_err(dev, "%pOF: could not parse node property\n", np);
> + return ret;
> + }
> +
> + reserve = 1;
> + if (num_configs)
> + reserve++;
> +
> + ret = pinctrl_utils_reserve_map(pctldev, map, &reserved_maps,
> + num_maps, reserve);
> + if (ret < 0)
> + goto exit;
> +
> + ret = pinctrl_utils_add_map_mux(pctldev, map,
> + &reserved_maps, num_maps, np->name,
> + pnode->name);
> + if (ret < 0)
> + goto exit;
> +
> + if (num_configs) {
> + ret = pinctrl_utils_add_map_configs(pctldev, map, &reserved_maps,
> + num_maps, np->name, configs,
> + num_configs, PIN_MAP_TYPE_CONFIGS_GROUP);
> + if (ret < 0)
> + goto exit;
> + }
> +
> +exit:
> + kfree(configs);
> + if (ret)
> + pinctrl_utils_free_map(pctldev, *map, *num_maps);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map_pinmux);
> +
> int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
> struct device_node *np, struct pinctrl_map **map,
> unsigned int *reserved_maps, unsigned int *num_maps,
> diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h
> index a14c950bc700..a171195b3615 100644
> --- a/drivers/pinctrl/pinconf.h
> +++ b/drivers/pinctrl/pinconf.h
> @@ -138,4 +138,8 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
> struct pinctrl_dev *pctldev,
> unsigned long **configs,
> unsigned int *nconfigs);
> +
> +int pinconf_generic_parse_dt_pinmux(struct device_node *np, struct device *dev,
> + unsigned int **pid, unsigned int **pmux,
> + unsigned int *npins);
> #endif
> diff --git a/include/linux/pinctrl/pinconf-generic.h b/include/linux/pinctrl/pinconf-generic.h
> index 53cfde98433d..1bcf071b860e 100644
> --- a/include/linux/pinctrl/pinconf-generic.h
> +++ b/include/linux/pinctrl/pinconf-generic.h
> @@ -232,4 +232,8 @@ static inline int pinconf_generic_dt_node_to_map_all(struct pinctrl_dev *pctldev
> PIN_MAP_TYPE_INVALID);
> }
>
> +int pinconf_generic_dt_node_to_map_pinmux(struct pinctrl_dev *pctldev,
> + struct device_node *np,
> + struct pinctrl_map **map,
> + unsigned int *num_maps);
> #endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */
--
Jerome
