root/drivers/pinctrl/cirrus/pinctrl-cs42l43.c
// SPDX-License-Identifier: GPL-2.0
//
// CS42L43 Pinctrl and GPIO driver
//
// Copyright (c) 2023 Cirrus Logic, Inc. and
//                    Cirrus Logic International Semiconductor Ltd.

#include <linux/array_size.h>
#include <linux/bits.h>
#include <linux/build_bug.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/mfd/cs42l43.h>
#include <linux/mfd/cs42l43-regs.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/string_choices.h>

#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinmux.h>

#include "../pinctrl-utils.h"

#define CS42L43_NUM_GPIOS 3

struct cs42l43_pin {
        struct gpio_chip gpio_chip;

        struct device *dev;
        struct regmap *regmap;
        bool shutters_locked;
};

struct cs42l43_pin_data {
        unsigned int reg;
        unsigned int shift;
        unsigned int mask;
};

#define CS42L43_PIN(_number, _name, _reg, _field) { \
        .number = _number, .name = _name, \
        .drv_data = &((struct cs42l43_pin_data){ \
                .reg = CS42L43_##_reg, \
                .shift = CS42L43_##_field##_DRV_SHIFT, \
                .mask = CS42L43_##_field##_DRV_MASK, \
        }), \
}

static const struct pinctrl_pin_desc cs42l43_pin_pins[] = {
        CS42L43_PIN(0,  "gpio1",        DRV_CTRL4,      GPIO1),
        CS42L43_PIN(1,  "gpio2",        DRV_CTRL4,      GPIO2),
        CS42L43_PIN(2,  "gpio3",        DRV_CTRL4,      GPIO3),
        CS42L43_PIN(3,  "asp_dout",     DRV_CTRL1,      ASP_DOUT),
        CS42L43_PIN(4,  "asp_fsync",    DRV_CTRL1,      ASP_FSYNC),
        CS42L43_PIN(5,  "asp_bclk",     DRV_CTRL1,      ASP_BCLK),
        CS42L43_PIN(6,  "pdmout2_clk",  DRV_CTRL3,      PDMOUT2_CLK),
        CS42L43_PIN(7,  "pdmout2_data", DRV_CTRL3,      PDMOUT2_DATA),
        CS42L43_PIN(8,  "pdmout1_clk",  DRV_CTRL3,      PDMOUT1_CLK),
        CS42L43_PIN(9,  "pdmout1_data", DRV_CTRL3,      PDMOUT1_DATA),
        CS42L43_PIN(10, "i2c_sda",      DRV_CTRL3,      I2C_SDA),
        CS42L43_PIN(11, "i2c_scl",      DRV_CTRL_5,     I2C_SCL),
        CS42L43_PIN(12, "spi_miso",     DRV_CTRL3,      SPI_MISO),
        CS42L43_PIN(13, "spi_sck",      DRV_CTRL_5,     SPI_SCK),
        CS42L43_PIN(14, "spi_ssb",      DRV_CTRL_5,     SPI_SSB),
};

static const unsigned int cs42l43_pin_gpio1_pins[] = { 0 };
static const unsigned int cs42l43_pin_gpio2_pins[] = { 1 };
static const unsigned int cs42l43_pin_gpio3_pins[] = { 2 };
static const unsigned int cs42l43_pin_asp_pins[] = { 3, 4, 5 };
static const unsigned int cs42l43_pin_pdmout2_pins[] = { 6, 7 };
static const unsigned int cs42l43_pin_pdmout1_pins[] = { 8, 9 };
static const unsigned int cs42l43_pin_i2c_pins[] = { 10, 11 };
static const unsigned int cs42l43_pin_spi_pins[] = { 12, 13, 14 };

#define CS42L43_PINGROUP(_name) \
        PINCTRL_PINGROUP(#_name, cs42l43_pin_##_name##_pins, \
                         ARRAY_SIZE(cs42l43_pin_##_name##_pins))

static const struct pingroup cs42l43_pin_groups[] = {
        CS42L43_PINGROUP(gpio1),
        CS42L43_PINGROUP(gpio2),
        CS42L43_PINGROUP(gpio3),
        CS42L43_PINGROUP(asp),
        CS42L43_PINGROUP(pdmout2),
        CS42L43_PINGROUP(pdmout1),
        CS42L43_PINGROUP(i2c),
        CS42L43_PINGROUP(spi),
};

static int cs42l43_pin_get_groups_count(struct pinctrl_dev *pctldev)
{
        return ARRAY_SIZE(cs42l43_pin_groups);
}

static const char *cs42l43_pin_get_group_name(struct pinctrl_dev *pctldev,
                                              unsigned int group_idx)
{
        return cs42l43_pin_groups[group_idx].name;
}

static int cs42l43_pin_get_group_pins(struct pinctrl_dev *pctldev,
                                      unsigned int group_idx,
                                      const unsigned int **pins,
                                      unsigned int *num_pins)
{
        *pins = cs42l43_pin_groups[group_idx].pins;
        *num_pins = cs42l43_pin_groups[group_idx].npins;

        return 0;
}

static const struct pinctrl_ops cs42l43_pin_group_ops = {
        .get_groups_count = cs42l43_pin_get_groups_count,
        .get_group_name = cs42l43_pin_get_group_name,
        .get_group_pins = cs42l43_pin_get_group_pins,
#if IS_ENABLED(CONFIG_OF)
        .dt_node_to_map = pinconf_generic_dt_node_to_map_all,
        .dt_free_map = pinconf_generic_dt_free_map,
#endif
};

enum cs42l43_pin_funcs {
        CS42L43_FUNC_GPIO,
        CS42L43_FUNC_SPDIF,
        CS42L43_FUNC_IRQ,
        CS42L43_FUNC_MIC_SHT,
        CS42L43_FUNC_SPK_SHT,
        CS42L43_FUNC_MAX
};

static const char * const cs42l43_pin_funcs[] = {
        "gpio", "spdif", "irq", "mic-shutter", "spk-shutter",
};

static const char * const cs42l43_pin_gpio_groups[] = { "gpio1", "gpio3" };
static const char * const cs42l43_pin_spdif_groups[] = { "gpio3" };
static const char * const cs42l43_pin_irq_groups[] = { "gpio1" };
static const char * const cs42l43_pin_shutter_groups[] = { "gpio1", "gpio2", "gpio3" };

static const struct pinfunction cs42l43_pin_func_groups[] = {
        PINCTRL_PINFUNCTION("gpio", cs42l43_pin_gpio_groups,
                            ARRAY_SIZE(cs42l43_pin_gpio_groups)),
        PINCTRL_PINFUNCTION("spdif", cs42l43_pin_spdif_groups,
                            ARRAY_SIZE(cs42l43_pin_spdif_groups)),
        PINCTRL_PINFUNCTION("irq",  cs42l43_pin_irq_groups,
                            ARRAY_SIZE(cs42l43_pin_irq_groups)),
        PINCTRL_PINFUNCTION("mic-shutter", cs42l43_pin_shutter_groups,
                            ARRAY_SIZE(cs42l43_pin_shutter_groups)),
        PINCTRL_PINFUNCTION("spk-shutter", cs42l43_pin_shutter_groups,
                            ARRAY_SIZE(cs42l43_pin_shutter_groups)),
};

static_assert(ARRAY_SIZE(cs42l43_pin_funcs) == CS42L43_FUNC_MAX);
static_assert(ARRAY_SIZE(cs42l43_pin_func_groups) == CS42L43_FUNC_MAX);

static int cs42l43_pin_get_func_count(struct pinctrl_dev *pctldev)
{
        return ARRAY_SIZE(cs42l43_pin_funcs);
}

static const char *cs42l43_pin_get_func_name(struct pinctrl_dev *pctldev,
                                             unsigned int func_idx)
{
        return cs42l43_pin_funcs[func_idx];
}

static int cs42l43_pin_get_func_groups(struct pinctrl_dev *pctldev,
                                       unsigned int func_idx,
                                       const char * const **groups,
                                       unsigned int * const num_groups)
{
        *groups = cs42l43_pin_func_groups[func_idx].groups;
        *num_groups = cs42l43_pin_func_groups[func_idx].ngroups;

        return 0;
}

static int cs42l43_pin_set_mux(struct pinctrl_dev *pctldev,
                               unsigned int func_idx, unsigned int group_idx)
{
        struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
        unsigned int reg, mask, val;

        dev_dbg(priv->dev, "Setting %s to %s\n",
                cs42l43_pin_groups[group_idx].name, cs42l43_pin_funcs[func_idx]);

        switch (func_idx) {
        case CS42L43_FUNC_MIC_SHT:
                reg = CS42L43_SHUTTER_CONTROL;
                mask = CS42L43_MIC_SHUTTER_CFG_MASK;
                val = 0x2 << (group_idx + CS42L43_MIC_SHUTTER_CFG_SHIFT);
                break;
        case CS42L43_FUNC_SPK_SHT:
                reg = CS42L43_SHUTTER_CONTROL;
                mask = CS42L43_SPK_SHUTTER_CFG_MASK;
                val = 0x2 << (group_idx + CS42L43_SPK_SHUTTER_CFG_SHIFT);
                break;
        default:
                reg = CS42L43_GPIO_FN_SEL;
                mask = BIT(group_idx + CS42L43_GPIO1_FN_SEL_SHIFT);
                val = (func_idx == CS42L43_FUNC_GPIO) ?
                                (0x1 << (group_idx + CS42L43_GPIO1_FN_SEL_SHIFT)) : 0;
                break;
        }

        if (priv->shutters_locked && reg == CS42L43_SHUTTER_CONTROL) {
                dev_err(priv->dev, "Shutter configuration not available\n");
                return -EPERM;
        }

        return regmap_update_bits(priv->regmap, reg, mask, val);
}

static int cs42l43_gpio_set_direction(struct pinctrl_dev *pctldev,
                                      struct pinctrl_gpio_range *range,
                                      unsigned int offset, bool input)
{
        struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
        unsigned int shift = offset + CS42L43_GPIO1_DIR_SHIFT;
        int ret;

        dev_dbg(priv->dev, "Setting gpio%d to %s\n",
                offset + 1, input ? "input" : "output");

        ret = pm_runtime_resume_and_get(priv->dev);
        if (ret) {
                dev_err(priv->dev, "Failed to resume for direction: %d\n", ret);
                return ret;
        }

        ret = regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL1,
                                 BIT(shift), !!input << shift);
        if (ret)
                dev_err(priv->dev, "Failed to set gpio%d direction: %d\n",
                        offset + 1, ret);

        pm_runtime_put(priv->dev);

        return ret;
}

static int cs42l43_gpio_request_enable(struct pinctrl_dev *pctldev,
                                       struct pinctrl_gpio_range *range,
                                       unsigned int offset)
{
        return cs42l43_pin_set_mux(pctldev, 0, offset);
}

static void cs42l43_gpio_disable_free(struct pinctrl_dev *pctldev,
                                      struct pinctrl_gpio_range *range,
                                      unsigned int offset)
{
        cs42l43_gpio_set_direction(pctldev, range, offset, true);
}

static const struct pinmux_ops cs42l43_pin_mux_ops = {
        .get_functions_count    = cs42l43_pin_get_func_count,
        .get_function_name      = cs42l43_pin_get_func_name,
        .get_function_groups    = cs42l43_pin_get_func_groups,

        .set_mux                = cs42l43_pin_set_mux,

        .gpio_request_enable    = cs42l43_gpio_request_enable,
        .gpio_disable_free      = cs42l43_gpio_disable_free,
        .gpio_set_direction     = cs42l43_gpio_set_direction,

        .strict                 = true,
};

static const unsigned int cs42l43_pin_drv_str_ma[] = { 1, 2, 4, 8, 9, 10, 12, 16 };

static int cs42l43_pin_get_drv_str(struct cs42l43_pin *priv, unsigned int pin)
{
        const struct cs42l43_pin_data *pdat = cs42l43_pin_pins[pin].drv_data;
        unsigned int val;
        int ret;

        ret = regmap_read(priv->regmap, pdat->reg, &val);
        if (ret)
                return ret;

        return cs42l43_pin_drv_str_ma[(val & pdat->mask) >> pdat->shift];
}

static int cs42l43_pin_set_drv_str(struct cs42l43_pin *priv, unsigned int pin,
                                   unsigned int ma)
{
        const struct cs42l43_pin_data *pdat = cs42l43_pin_pins[pin].drv_data;
        int i;

        for (i = 0; i < ARRAY_SIZE(cs42l43_pin_drv_str_ma); i++) {
                if (ma == cs42l43_pin_drv_str_ma[i]) {
                        if ((i << pdat->shift) > pdat->mask)
                                goto err;

                        dev_dbg(priv->dev, "Set drive strength for %s to %d mA\n",
                                cs42l43_pin_pins[pin].name, ma);

                        return regmap_update_bits(priv->regmap, pdat->reg,
                                                  pdat->mask, i << pdat->shift);
                }
        }

err:
        dev_err(priv->dev, "Invalid drive strength for %s: %d mA\n",
                cs42l43_pin_pins[pin].name, ma);
        return -EINVAL;
}

static int cs42l43_pin_get_db(struct cs42l43_pin *priv, unsigned int pin)
{
        unsigned int val;
        int ret;

        if (pin >= CS42L43_NUM_GPIOS)
                return -ENOTSUPP;

        ret = regmap_read(priv->regmap, CS42L43_GPIO_CTRL2, &val);
        if (ret)
                return ret;

        if (val & (CS42L43_GPIO1_DEGLITCH_BYP_MASK << pin))
                return 0;

        return 85; // Debounce is roughly 85uS
}

static int cs42l43_pin_set_db(struct cs42l43_pin *priv, unsigned int pin,
                              unsigned int us)
{
        if (pin >= CS42L43_NUM_GPIOS)
                return -ENOTSUPP;

        dev_dbg(priv->dev, "Set debounce %s for %s\n",
                str_on_off(us), cs42l43_pin_pins[pin].name);

        return regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL2,
                                  CS42L43_GPIO1_DEGLITCH_BYP_MASK << pin,
                                  !!us << pin);
}

static int cs42l43_pin_config_get(struct pinctrl_dev *pctldev,
                                  unsigned int pin, unsigned long *config)
{
        struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
        unsigned int param = pinconf_to_config_param(*config);
        int ret;

        switch (param) {
        case PIN_CONFIG_DRIVE_STRENGTH:
                ret = cs42l43_pin_get_drv_str(priv, pin);
                if (ret < 0)
                        return ret;
                break;
        case PIN_CONFIG_INPUT_DEBOUNCE:
                ret = cs42l43_pin_get_db(priv, pin);
                if (ret < 0)
                        return ret;
                break;
        default:
                return -ENOTSUPP;
        }

        *config = pinconf_to_config_packed(param, ret);

        return 0;
}

static int cs42l43_pin_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
                                  unsigned long *configs, unsigned int num_configs)
{
        struct cs42l43_pin *priv = pinctrl_dev_get_drvdata(pctldev);
        unsigned int val;
        int ret;

        while (num_configs) {
                val = pinconf_to_config_argument(*configs);

                switch (pinconf_to_config_param(*configs)) {
                case PIN_CONFIG_DRIVE_STRENGTH:
                        ret = cs42l43_pin_set_drv_str(priv, pin, val);
                        if (ret)
                                return ret;
                        break;
                case PIN_CONFIG_INPUT_DEBOUNCE:
                        ret = cs42l43_pin_set_db(priv, pin, val);
                        if (ret)
                                return ret;
                        break;
                default:
                        return -ENOTSUPP;
                }

                configs++;
                num_configs--;
        }

        return 0;
}

static int cs42l43_pin_config_group_get(struct pinctrl_dev *pctldev,
                                        unsigned int selector, unsigned long *config)
{
        int i, ret;

        for (i = 0; i < cs42l43_pin_groups[selector].npins; ++i) {
                ret = cs42l43_pin_config_get(pctldev,
                                             cs42l43_pin_groups[selector].pins[i],
                                             config);
                if (ret)
                        return ret;
        }

        return 0;
}

static int cs42l43_pin_config_group_set(struct pinctrl_dev *pctldev,
                                        unsigned int selector,
                                        unsigned long *configs,
                                        unsigned int num_configs)
{
        int i, ret;

        for (i = 0; i < cs42l43_pin_groups[selector].npins; ++i) {
                ret = cs42l43_pin_config_set(pctldev,
                                             cs42l43_pin_groups[selector].pins[i],
                                             configs, num_configs);
                if (ret)
                        return ret;
        }

        return 0;
}

static const struct pinconf_ops cs42l43_pin_conf_ops = {
        .is_generic             = true,

        .pin_config_get         = cs42l43_pin_config_get,
        .pin_config_set         = cs42l43_pin_config_set,
        .pin_config_group_get   = cs42l43_pin_config_group_get,
        .pin_config_group_set   = cs42l43_pin_config_group_set,
};

static const struct pinctrl_desc cs42l43_pin_desc = {
        .name           = "cs42l43-pinctrl",
        .owner          = THIS_MODULE,

        .pins           = cs42l43_pin_pins,
        .npins          = ARRAY_SIZE(cs42l43_pin_pins),

        .pctlops        = &cs42l43_pin_group_ops,
        .pmxops         = &cs42l43_pin_mux_ops,
        .confops        = &cs42l43_pin_conf_ops,
};

static int cs42l43_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
        struct cs42l43_pin *priv = gpiochip_get_data(chip);
        unsigned int val;
        int ret;

        ret = pm_runtime_resume_and_get(priv->dev);
        if (ret) {
                dev_err(priv->dev, "Failed to resume for get: %d\n", ret);
                return ret;
        }

        ret = regmap_read(priv->regmap, CS42L43_GPIO_STS, &val);
        if (ret)
                dev_err(priv->dev, "Failed to get gpio%d: %d\n", offset + 1, ret);
        else
                ret = !!(val & BIT(offset + CS42L43_GPIO1_STS_SHIFT));

        pm_runtime_put(priv->dev);

        return ret;
}

static int cs42l43_gpio_set(struct gpio_chip *chip, unsigned int offset,
                            int value)
{
        struct cs42l43_pin *priv = gpiochip_get_data(chip);
        unsigned int shift = offset + CS42L43_GPIO1_LVL_SHIFT;
        int ret;

        dev_dbg(priv->dev, "Setting gpio%d to %s\n",
                offset + 1, str_high_low(value));

        ret = pm_runtime_resume_and_get(priv->dev);
        if (ret)
                return ret;

        ret = regmap_update_bits(priv->regmap, CS42L43_GPIO_CTRL1,
                                 BIT(shift), value << shift);
        if (ret)
                return ret;

        pm_runtime_put(priv->dev);

        return 0;
}

static int cs42l43_gpio_direction_out(struct gpio_chip *chip,
                                      unsigned int offset, int value)
{
        int ret;

        ret = cs42l43_gpio_set(chip, offset, value);
        if (ret)
                return ret;

        return pinctrl_gpio_direction_output(chip, offset);
}

static int cs42l43_gpio_add_pin_ranges(struct gpio_chip *chip)
{
        struct cs42l43_pin *priv = gpiochip_get_data(chip);
        int ret;

        ret = gpiochip_add_pin_range(&priv->gpio_chip, priv->gpio_chip.label,
                                     0, 0, CS42L43_NUM_GPIOS);
        if (ret)
                dev_err(priv->dev, "Failed to add GPIO pin range: %d\n", ret);

        return ret;
}

static void cs42l43_fwnode_put(void *data)
{
        fwnode_handle_put(data);
}

static int cs42l43_pin_probe(struct platform_device *pdev)
{
        struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
        struct cs42l43_pin *priv;
        struct pinctrl_dev *pctldev;
        struct fwnode_handle *fwnode = dev_fwnode(cs42l43->dev);
        int ret;

        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        priv->dev = &pdev->dev;
        priv->regmap = cs42l43->regmap;

        priv->shutters_locked = cs42l43->hw_lock;

        priv->gpio_chip.request = gpiochip_generic_request;
        priv->gpio_chip.free = gpiochip_generic_free;
        priv->gpio_chip.direction_input = pinctrl_gpio_direction_input;
        priv->gpio_chip.direction_output = cs42l43_gpio_direction_out;
        priv->gpio_chip.add_pin_ranges = cs42l43_gpio_add_pin_ranges;
        priv->gpio_chip.get = cs42l43_gpio_get;
        priv->gpio_chip.set = cs42l43_gpio_set;
        priv->gpio_chip.label = dev_name(priv->dev);
        priv->gpio_chip.parent = priv->dev;
        priv->gpio_chip.can_sleep = true;
        priv->gpio_chip.base = -1;
        priv->gpio_chip.ngpio = CS42L43_NUM_GPIOS;

        if (is_of_node(fwnode)) {
                struct fwnode_handle *child;

                child = fwnode_get_named_child_node(fwnode, "pinctrl");
                if (child) {
                        ret = devm_add_action_or_reset(&pdev->dev,
                                cs42l43_fwnode_put, child);
                        if (ret)
                                return ret;

                        if (!child->dev)
                                child->dev = priv->dev;
                        fwnode = child;
                }
        }

        priv->gpio_chip.fwnode = fwnode;

        device_set_node(priv->dev, fwnode);

        devm_pm_runtime_enable(priv->dev);
        pm_runtime_idle(priv->dev);

        pctldev = devm_pinctrl_register(priv->dev, &cs42l43_pin_desc, priv);
        if (IS_ERR(pctldev))
                return dev_err_probe(priv->dev, PTR_ERR(pctldev),
                                     "Failed to register pinctrl\n");

        ret = devm_gpiochip_add_data(priv->dev, &priv->gpio_chip, priv);
        if (ret)
                return dev_err_probe(priv->dev, ret,
                                     "Failed to register gpiochip\n");

        return 0;
}

static const struct platform_device_id cs42l43_pin_id_table[] = {
        { "cs42l43-pinctrl", },
        {}
};
MODULE_DEVICE_TABLE(platform, cs42l43_pin_id_table);

static struct platform_driver cs42l43_pin_driver = {
        .driver = {
                .name   = "cs42l43-pinctrl",
        },
        .probe          = cs42l43_pin_probe,
        .id_table       = cs42l43_pin_id_table,
};
module_platform_driver(cs42l43_pin_driver);

MODULE_DESCRIPTION("CS42L43 Pinctrl Driver");
MODULE_AUTHOR("Charles Keepax <ckeepax@opensource.cirrus.com>");
MODULE_LICENSE("GPL");