Re: [PATCH v3 02/12] pinctrl: axp209: add pinctrl features

Maxime Ripard
2017-10-02T20:37:44Z

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On Mon, Oct 02, 2017 at 12:08:44PM +0000, Quentin Schulz wrote:
> The X-Powers AXP209 has 3 GPIOs. GPIO0/1 can each act either as a GPIO,
> an ADC or a LDO regulator. GPIO2 can only act as a GPIO.
>
> This adds the pinctrl features to the driver so GPIO0/1 can be used as
> ADC or LDO regulator.
>
> Signed-off-by: Quentin Schulz <quentin.schulz-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> ---
> .../devicetree/bindings/pinctrl/pinctrl-axp209.txt | 28 +-
> drivers/pinctrl/pinctrl-axp209.c | 293 +++++++++++++++++++--
> 2 files changed, 300 insertions(+), 21 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-axp209.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-axp209.txt
> index a6611304dd3c..388c04492afd 100644
> --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-axp209.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-axp209.txt
> @@ -1,4 +1,4 @@
> -AXP209 GPIO controller
> +AXP209 GPIO & pinctrl controller
>
> This driver follows the usual GPIO bindings found in
> Documentation/devicetree/bindings/gpio/gpio.txt
> @@ -28,3 +28,29 @@ axp209: pmic@34 {
> #gpio-cells = <2>;
> };
> };
> +
> +The GPIOs can be muxed to other functions and therefore, must be a subnode of
> +axp_gpio.
> +
> +Example:
> +
> +&axp_gpio {
> + gpio0_adc: gpio0_adc {
> + pins = "GPIO0";
> + function = "adc";
> + };
> +};
> +
> +&example_node {
> + pinctrl-names = "default";
> + pinctrl-0 = <&gpio0_adc>;
> +};
> +
> +GPIOs and their functions
> +-------------------------
> +
> +GPIO | Functions
> +------------------------
> +GPIO0 | gpio_in, gpio_out, ldo, adc
> +GPIO1 | gpio_in, gpio_out, ldo, adc
> +GPIO2 | gpio_in, gpio_out
> diff --git a/drivers/pinctrl/pinctrl-axp209.c b/drivers/pinctrl/pinctrl-axp209.c
> index 4a346b7b4172..96ef0cc28762 100644
> --- a/drivers/pinctrl/pinctrl-axp209.c
> +++ b/drivers/pinctrl/pinctrl-axp209.c
> @@ -1,7 +1,8 @@
> /*
> - * AXP20x GPIO driver
> + * AXP20x pinctrl and GPIO driver
> *
> * Copyright (C) 2016 Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> + * Copyright (C) 2017 Quentin Schulz <quentin.schulz-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> *
> * This program is free software; you can redistribute it and/or modify it
> * under the terms of the GNU General Public License as published by the
> @@ -22,14 +23,57 @@
> #include <linux/regmap.h>
> #include <linux/slab.h>
>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/pinctrl/pinmux.h>
> +#include <linux/pinctrl/pinconf-generic.h>
> +

You should order the headers by alphabetical order.

> #define AXP20X_GPIO_FUNCTIONS 0x7
> #define AXP20X_GPIO_FUNCTION_OUT_LOW 0
> #define AXP20X_GPIO_FUNCTION_OUT_HIGH 1
> #define AXP20X_GPIO_FUNCTION_INPUT 2
>
> +#define AXP20X_FUNC_GPIO_OUT 0
> +#define AXP20X_FUNC_GPIO_IN 1
> +#define AXP20X_FUNC_LDO 2
> +#define AXP20X_FUNC_ADC 3
> +#define AXP20X_FUNCS_NB 4
> +
> +struct axp20x_pctrl_desc {
> + const struct pinctrl_pin_desc *pins;
> + unsigned int npins;
> + /* Stores the pins supporting LDO function. Bit offset is pin number. */
> + unsigned int ldo_mask;
> + /* Stores the pins supporting ADC function. Bit offset is pin number. */
> + unsigned int adc_mask;

You can use u8 here.

> +};
> +
> +struct axp20x_pinctrl_function {
> + const char *name;
> + unsigned int muxval;
> + const char **groups;
> + unsigned int ngroups;
> +};
> +
> struct axp20x_gpio {
> struct gpio_chip chip;
> struct regmap *regmap;
> + struct pinctrl_dev *pctl_dev;
> + struct device *dev;
> + const struct axp20x_pctrl_desc *desc;
> + struct axp20x_pinctrl_function funcs[AXP20X_FUNCS_NB];
> +};
> +
> +static const struct pinctrl_pin_desc axp209_pins[] = {
> + PINCTRL_PIN(0, "GPIO0"),
> + PINCTRL_PIN(1, "GPIO1"),
> + PINCTRL_PIN(2, "GPIO2"),
> +};
> +
> +static const struct axp20x_pctrl_desc axp20x_data = {
> + .pins = axp209_pins,
> + .npins = ARRAY_SIZE(axp209_pins),
> + .ldo_mask = BIT(0) | BIT(1),
> + .adc_mask = BIT(0) | BIT(1),
> };
>
> static int axp20x_gpio_get_reg(unsigned offset)
> @@ -48,16 +92,7 @@ static int axp20x_gpio_get_reg(unsigned offset)
>
> static int axp20x_gpio_input(struct gpio_chip *chip, unsigned offset)
> {
> - struct axp20x_gpio *gpio = gpiochip_get_data(chip);
> - int reg;
> -
> - reg = axp20x_gpio_get_reg(offset);
> - if (reg < 0)
> - return reg;
> -
> - return regmap_update_bits(gpio->regmap, reg,
> - AXP20X_GPIO_FUNCTIONS,
> - AXP20X_GPIO_FUNCTION_INPUT);
> + return pinctrl_gpio_direction_input(chip->base + offset);
> }
>
> static int axp20x_gpio_get(struct gpio_chip *chip, unsigned offset)
> @@ -105,29 +140,210 @@ static int axp20x_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
> static int axp20x_gpio_output(struct gpio_chip *chip, unsigned offset,
> int value)
> {
> + chip->set(chip, offset, value);
> +
> + return 0;
> +}
> +
> +static void axp20x_gpio_set(struct gpio_chip *chip, unsigned offset,
> + int value)
> +{
> struct axp20x_gpio *gpio = gpiochip_get_data(chip);
> int reg;
>
> reg = axp20x_gpio_get_reg(offset);
> if (reg < 0)
> + return;
> +
> + regmap_update_bits(gpio->regmap, reg,
> + AXP20X_GPIO_FUNCTIONS,
> + value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
> + AXP20X_GPIO_FUNCTION_OUT_LOW);
> +}
> +
> +static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
> + u8 config)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> + int reg;
> +
> + reg = axp20x_gpio_get_reg(offset);
> + if (reg < 0)
> return reg;
>
> - return regmap_update_bits(gpio->regmap, reg,
> - AXP20X_GPIO_FUNCTIONS,
> - value ? AXP20X_GPIO_FUNCTION_OUT_HIGH
> - : AXP20X_GPIO_FUNCTION_OUT_LOW);
> + return regmap_update_bits(gpio->regmap, reg, AXP20X_GPIO_FUNCTIONS,
> + config);
> }
>
> -static void axp20x_gpio_set(struct gpio_chip *chip, unsigned offset,
> - int value)
> +static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + return ARRAY_SIZE(gpio->funcs);
> +}
> +
> +static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
> + unsigned int selector)
> {
> - axp20x_gpio_output(chip, offset, value);
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + return gpio->funcs[selector].name;
> +}
> +
> +static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
> + unsigned int selector,
> + const char * const **groups,
> + unsigned int *num_groups)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + *groups = gpio->funcs[selector].groups;
> + *num_groups = gpio->funcs[selector].ngroups;
> +
> + return 0;
> +}
> +
> +static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
> + unsigned int function, unsigned int group)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> + unsigned int mask;
> +
> + /* Every pin supports GPIO_OUT and GPIO_IN functions */
> + if (function <= AXP20X_FUNC_GPIO_IN)
> + return axp20x_pmx_set(pctldev, group,
> + gpio->funcs[function].muxval);
> +
> + if (function == AXP20X_FUNC_LDO)
> + mask = gpio->desc->ldo_mask;
> + else
> + mask = gpio->desc->adc_mask;
> +
> + if (!(BIT(group) & mask))
> + return -EINVAL;
> +
> + return axp20x_pmx_set(pctldev, group, gpio->funcs[function].muxval);
> +}
> +
> +static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
> + struct pinctrl_gpio_range *range,
> + unsigned int offset, bool input)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + if (input)
> + return axp20x_pmx_set(pctldev, offset,
> + gpio->funcs[AXP20X_FUNC_GPIO_IN].muxval);
> +
> + return axp20x_pmx_set(pctldev, offset,
> + gpio->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
> +}
> +
> +static const struct pinmux_ops axp20x_pmx_ops = {
> + .get_functions_count = axp20x_pmx_func_cnt,
> + .get_function_name = axp20x_pmx_func_name,
> + .get_function_groups = axp20x_pmx_func_groups,
> + .set_mux = axp20x_pmx_set_mux,
> + .gpio_set_direction = axp20x_pmx_gpio_set_direction,
> + .strict = true,
> +};
> +
> +static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + return gpio->desc->npins;
> +}
> +
> +static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
> + const unsigned int **pins, unsigned int *num_pins)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + *pins = (unsigned int *)&gpio->desc->pins[selector];
> + *num_pins = 1;
> +
> + return 0;
> +}
> +
> +static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
> + unsigned int selector)
> +{
> + struct axp20x_gpio *gpio = pinctrl_dev_get_drvdata(pctldev);
> +
> + return gpio->desc->pins[selector].name;
> +}
> +
> +static const struct pinctrl_ops axp20x_pctrl_ops = {
> + .dt_node_to_map = pinconf_generic_dt_node_to_map_group,
> + .dt_free_map = pinconf_generic_dt_free_map,
> + .get_groups_count = axp20x_groups_cnt,
> + .get_group_name = axp20x_group_name,
> + .get_group_pins = axp20x_group_pins,
> +};
> +
> +static void axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
> + unsigned int mask_len,
> + struct axp20x_pinctrl_function *func,
> + const struct pinctrl_pin_desc *pins)
> +{
> + unsigned long int mask_cpy = mask;
> + const char **group;
> + unsigned int ngroups = hweight8(mask);
> + int bit;
> +
> + func->ngroups = ngroups;
> + if (func->ngroups > 0) {
> + func->groups = devm_kzalloc(dev, ngroups * sizeof(const char *),
> + GFP_KERNEL);
> + group = func->groups;
> + for_each_set_bit(bit, &mask_cpy, mask_len) {
> + *group = pins[bit].name;
> + group++;
> + }
> + }
> +}
> +
> +static void axp20x_build_funcs_groups(struct platform_device *pdev)
> +{
> + struct axp20x_gpio *gpio = platform_get_drvdata(pdev);
> + int i, pin;
> +
> + gpio->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
> + gpio->funcs[AXP20X_FUNC_GPIO_OUT].muxval = 0x0;
> + gpio->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
> + gpio->funcs[AXP20X_FUNC_GPIO_IN].muxval = 0x2;

Why do you need hexadecimal values here?

> + gpio->funcs[AXP20X_FUNC_LDO].name = "ldo";
> + gpio->funcs[AXP20X_FUNC_LDO].muxval = 0x3;
> + gpio->funcs[AXP20X_FUNC_ADC].name = "adc";
> + gpio->funcs[AXP20X_FUNC_ADC].muxval = 0x4;

And you probably can define that statically.

> + /* Every pin supports GPIO_OUT and GPIO_IN functions */
> + for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
> + gpio->funcs[i].ngroups = gpio->desc->npins;
> + gpio->funcs[i].groups = devm_kzalloc(&pdev->dev,
> + gpio->desc->npins * sizeof(const char *),
> + GFP_KERNEL);
> + for (pin = 0; pin < gpio->desc->npins; pin++)
> + gpio->funcs[i].groups[pin] = gpio->desc->pins[pin].name;
> + }
> +
> + axp20x_funcs_groups_from_mask(&pdev->dev, gpio->desc->ldo_mask,
> + gpio->desc->npins,
> + &gpio->funcs[AXP20X_FUNC_LDO],
> + gpio->desc->pins);
> +
> + axp20x_funcs_groups_from_mask(&pdev->dev, gpio->desc->adc_mask,
> + gpio->desc->npins,
> + &gpio->funcs[AXP20X_FUNC_ADC],
> + gpio->desc->pins);
> }
>
> static int axp20x_gpio_probe(struct platform_device *pdev)
> {
> struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
> struct axp20x_gpio *gpio;
> + struct pinctrl_desc *pctrl_desc;
> int ret;
>
> if (!of_device_is_available(pdev->dev.of_node))
> @@ -144,6 +360,8 @@ static int axp20x_gpio_probe(struct platform_device *pdev)
>
> gpio->chip.base = -1;
> gpio->chip.can_sleep = true;
> + gpio->chip.request = gpiochip_generic_request;
> + gpio->chip.free = gpiochip_generic_free;
> gpio->chip.parent = &pdev->dev;
> gpio->chip.label = dev_name(&pdev->dev);
> gpio->chip.owner = THIS_MODULE;
> @@ -154,15 +372,49 @@ static int axp20x_gpio_probe(struct platform_device *pdev)
> gpio->chip.direction_output = axp20x_gpio_output;
> gpio->chip.ngpio = 3;
>
> + gpio->desc = &axp20x_data;
> +
> gpio->regmap = axp20x->regmap;
>
> + gpio->dev = &pdev->dev;
> +

Why do you need new lines between each affectation?

> + platform_set_drvdata(pdev, gpio);
> +
> + axp20x_build_funcs_groups(pdev);
> +
> + pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
> + if (!pctrl_desc)
> + return -ENOMEM;
> +
> + pctrl_desc->name = dev_name(&pdev->dev);
> + pctrl_desc->owner = THIS_MODULE;
> + pctrl_desc->pins = gpio->desc->pins;
> + pctrl_desc->npins = gpio->desc->npins;
> + pctrl_desc->pctlops = &axp20x_pctrl_ops;
> + pctrl_desc->pmxops = &axp20x_pmx_ops;
> +
> + gpio->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, gpio);
> + if (IS_ERR(gpio->pctl_dev)) {
> + dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
> + return PTR_ERR(gpio->pctl_dev);
> + }
> +
> ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
> if (ret) {
> dev_err(&pdev->dev, "Failed to register GPIO chip\n");
> return ret;
> }
>
> - dev_info(&pdev->dev, "AXP209 GPIO driver loaded\n");
> + ret = gpiochip_add_pin_range(&gpio->chip, dev_name(&pdev->dev),
> + gpio->desc->pins->number,
> + gpio->desc->pins->number,
> + gpio->desc->npins);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to add pin range\n");
> + return ret;
> + }
> +
> + dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
>
> return 0;
> }
> @@ -184,5 +436,6 @@ static struct platform_driver axp20x_gpio_driver = {
> module_platform_driver(axp20x_gpio_driver);
>
> MODULE_AUTHOR("Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>");
> -MODULE_DESCRIPTION("AXP20x PMIC GPIO driver");
> +MODULE_AUTHOR("Quentin Schulz <quentin.schulz-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>");
> +MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
> MODULE_LICENSE("GPL");

Looks much better otherwise, thanks!
Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering