linux/drivers/pinctrl/pinctrl-axp209.c
Quentin Schulz 48e706fbc5 pinctrl: axp209: add programmable gpio_status_offset
To prepare for patches that will add support for a new PMIC that has a
different GPIO input status register, add a gpio_status_offset within
axp20x_pctl structure and use it.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-07 10:07:19 +01:00

456 lines
12 KiB
C

/*
* AXP20x pinctrl and GPIO driver
*
* Copyright (C) 2016 Maxime Ripard <maxime.ripard@free-electrons.com>
* Copyright (C) 2017 Quentin Schulz <quentin.schulz@free-electrons.com>
*
* 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
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/axp20x.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#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
#define AXP20X_MUX_GPIO_OUT 0
#define AXP20X_MUX_GPIO_IN BIT(1)
#define AXP20X_MUX_ADC BIT(2)
struct axp20x_pctrl_desc {
const struct pinctrl_pin_desc *pins;
unsigned int npins;
/* Stores the pins supporting LDO function. Bit offset is pin number. */
u8 ldo_mask;
/* Stores the pins supporting ADC function. Bit offset is pin number. */
u8 adc_mask;
u8 gpio_status_offset;
};
struct axp20x_pinctrl_function {
const char *name;
unsigned int muxval;
const char **groups;
unsigned int ngroups;
};
struct axp20x_pctl {
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),
.gpio_status_offset = 4,
};
static int axp20x_gpio_get_reg(unsigned int offset)
{
switch (offset) {
case 0:
return AXP20X_GPIO0_CTRL;
case 1:
return AXP20X_GPIO1_CTRL;
case 2:
return AXP20X_GPIO2_CTRL;
}
return -EINVAL;
}
static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
{
return pinctrl_gpio_direction_input(chip->base + offset);
}
static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
struct axp20x_pctl *pctl = gpiochip_get_data(chip);
unsigned int val;
int ret;
ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
if (ret)
return ret;
return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
}
static int axp20x_gpio_get_direction(struct gpio_chip *chip,
unsigned int offset)
{
struct axp20x_pctl *pctl = gpiochip_get_data(chip);
unsigned int val;
int reg, ret;
reg = axp20x_gpio_get_reg(offset);
if (reg < 0)
return reg;
ret = regmap_read(pctl->regmap, reg, &val);
if (ret)
return ret;
/*
* This shouldn't really happen if the pin is in use already,
* or if it's not in use yet, it doesn't matter since we're
* going to change the value soon anyway. Default to output.
*/
if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
return 0;
/*
* The GPIO directions are the three lowest values.
* 2 is input, 0 and 1 are output
*/
return val & 2;
}
static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
int value)
{
chip->set(chip, offset, value);
return 0;
}
static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
int value)
{
struct axp20x_pctl *pctl = gpiochip_get_data(chip);
int reg;
reg = axp20x_gpio_get_reg(offset);
if (reg < 0)
return;
regmap_update_bits(pctl->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_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
int reg;
reg = axp20x_gpio_get_reg(offset);
if (reg < 0)
return reg;
return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
config);
}
static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
{
struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
return ARRAY_SIZE(pctl->funcs);
}
static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
unsigned int selector)
{
struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
return pctl->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_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
*groups = pctl->funcs[selector].groups;
*num_groups = pctl->funcs[selector].ngroups;
return 0;
}
static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
unsigned int function, unsigned int group)
{
struct axp20x_pctl *pctl = 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,
pctl->funcs[function].muxval);
if (function == AXP20X_FUNC_LDO)
mask = pctl->desc->ldo_mask;
else
mask = pctl->desc->adc_mask;
if (!(BIT(group) & mask))
return -EINVAL;
/*
* We let the regulator framework handle the LDO muxing as muxing bits
* are basically also regulators on/off bits. It's better not to enforce
* any state of the regulator when selecting LDO mux so that we don't
* interfere with the regulator driver.
*/
if (function == AXP20X_FUNC_LDO)
return 0;
return axp20x_pmx_set(pctldev, group, pctl->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_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
if (input)
return axp20x_pmx_set(pctldev, offset,
pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
return axp20x_pmx_set(pctldev, offset,
pctl->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_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
return pctl->desc->npins;
}
static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
const unsigned int **pins, unsigned int *num_pins)
{
struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
*pins = (unsigned int *)&pctl->desc->pins[selector];
*num_pins = 1;
return 0;
}
static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
unsigned int selector)
{
struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
return pctl->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_pctl *pctl = platform_get_drvdata(pdev);
int i, pin, npins = pctl->desc->npins;
pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
/*
* Muxval for LDO is useless as we won't use it.
* See comment in axp20x_pmx_set_mux.
*/
pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
pctl->funcs[AXP20X_FUNC_ADC].muxval = AXP20X_MUX_ADC;
/* Every pin supports GPIO_OUT and GPIO_IN functions */
for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
pctl->funcs[i].ngroups = npins;
pctl->funcs[i].groups = devm_kzalloc(&pdev->dev,
npins * sizeof(char *),
GFP_KERNEL);
for (pin = 0; pin < npins; pin++)
pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
}
axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
npins, &pctl->funcs[AXP20X_FUNC_LDO],
pctl->desc->pins);
axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
npins, &pctl->funcs[AXP20X_FUNC_ADC],
pctl->desc->pins);
}
static int axp20x_pctl_probe(struct platform_device *pdev)
{
struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
struct axp20x_pctl *pctl;
struct pinctrl_desc *pctrl_desc;
int ret;
if (!of_device_is_available(pdev->dev.of_node))
return -ENODEV;
if (!axp20x) {
dev_err(&pdev->dev, "Parent drvdata not set\n");
return -EINVAL;
}
pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
if (!pctl)
return -ENOMEM;
pctl->chip.base = -1;
pctl->chip.can_sleep = true;
pctl->chip.request = gpiochip_generic_request;
pctl->chip.free = gpiochip_generic_free;
pctl->chip.parent = &pdev->dev;
pctl->chip.label = dev_name(&pdev->dev);
pctl->chip.owner = THIS_MODULE;
pctl->chip.get = axp20x_gpio_get;
pctl->chip.get_direction = axp20x_gpio_get_direction;
pctl->chip.set = axp20x_gpio_set;
pctl->chip.direction_input = axp20x_gpio_input;
pctl->chip.direction_output = axp20x_gpio_output;
pctl->chip.ngpio = 3;
pctl->desc = &axp20x_data;
pctl->regmap = axp20x->regmap;
pctl->dev = &pdev->dev;
platform_set_drvdata(pdev, pctl);
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 = pctl->desc->pins;
pctrl_desc->npins = pctl->desc->npins;
pctrl_desc->pctlops = &axp20x_pctrl_ops;
pctrl_desc->pmxops = &axp20x_pmx_ops;
pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
if (IS_ERR(pctl->pctl_dev)) {
dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
return PTR_ERR(pctl->pctl_dev);
}
ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
if (ret) {
dev_err(&pdev->dev, "Failed to register GPIO chip\n");
return ret;
}
ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
pctl->desc->pins->number,
pctl->desc->pins->number,
pctl->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;
}
static const struct of_device_id axp20x_pctl_match[] = {
{ .compatible = "x-powers,axp209-gpio" },
{ }
};
MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
static struct platform_driver axp20x_pctl_driver = {
.probe = axp20x_pctl_probe,
.driver = {
.name = "axp20x-gpio",
.of_match_table = axp20x_pctl_match,
},
};
module_platform_driver(axp20x_pctl_driver);
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
MODULE_LICENSE("GPL");