linux/drivers/pinctrl/pinctrl-axp209.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * AXP20x pinctrl and GPIO driver
   4 *
   5 * Copyright (C) 2016 Maxime Ripard <maxime.ripard@free-electrons.com>
   6 * Copyright (C) 2017 Quentin Schulz <quentin.schulz@free-electrons.com>
   7 */
   8
   9#include <linux/bitops.h>
  10#include <linux/device.h>
  11#include <linux/gpio/driver.h>
  12#include <linux/init.h>
  13#include <linux/interrupt.h>
  14#include <linux/kernel.h>
  15#include <linux/mfd/axp20x.h>
  16#include <linux/module.h>
  17#include <linux/of.h>
  18#include <linux/of_device.h>
  19#include <linux/pinctrl/pinconf-generic.h>
  20#include <linux/pinctrl/pinctrl.h>
  21#include <linux/pinctrl/pinmux.h>
  22#include <linux/platform_device.h>
  23#include <linux/regmap.h>
  24#include <linux/slab.h>
  25
  26#define AXP20X_GPIO_FUNCTIONS           0x7
  27#define AXP20X_GPIO_FUNCTION_OUT_LOW    0
  28#define AXP20X_GPIO_FUNCTION_OUT_HIGH   1
  29#define AXP20X_GPIO_FUNCTION_INPUT      2
  30
  31#define AXP20X_FUNC_GPIO_OUT            0
  32#define AXP20X_FUNC_GPIO_IN             1
  33#define AXP20X_FUNC_LDO                 2
  34#define AXP20X_FUNC_ADC                 3
  35#define AXP20X_FUNCS_NB                 4
  36
  37#define AXP20X_MUX_GPIO_OUT             0
  38#define AXP20X_MUX_GPIO_IN              BIT(1)
  39#define AXP20X_MUX_ADC                  BIT(2)
  40
  41#define AXP813_MUX_ADC                  (BIT(2) | BIT(0))
  42
  43struct axp20x_pctrl_desc {
  44        const struct pinctrl_pin_desc   *pins;
  45        unsigned int                    npins;
  46        /* Stores the pins supporting LDO function. Bit offset is pin number. */
  47        u8                              ldo_mask;
  48        /* Stores the pins supporting ADC function. Bit offset is pin number. */
  49        u8                              adc_mask;
  50        u8                              gpio_status_offset;
  51        u8                              adc_mux;
  52};
  53
  54struct axp20x_pinctrl_function {
  55        const char      *name;
  56        unsigned int    muxval;
  57        const char      **groups;
  58        unsigned int    ngroups;
  59};
  60
  61struct axp20x_pctl {
  62        struct gpio_chip        chip;
  63        struct regmap           *regmap;
  64        struct pinctrl_dev                      *pctl_dev;
  65        struct device                           *dev;
  66        const struct axp20x_pctrl_desc          *desc;
  67        struct axp20x_pinctrl_function          funcs[AXP20X_FUNCS_NB];
  68};
  69
  70static const struct pinctrl_pin_desc axp209_pins[] = {
  71        PINCTRL_PIN(0, "GPIO0"),
  72        PINCTRL_PIN(1, "GPIO1"),
  73        PINCTRL_PIN(2, "GPIO2"),
  74};
  75
  76static const struct pinctrl_pin_desc axp813_pins[] = {
  77        PINCTRL_PIN(0, "GPIO0"),
  78        PINCTRL_PIN(1, "GPIO1"),
  79};
  80
  81static const struct axp20x_pctrl_desc axp20x_data = {
  82        .pins   = axp209_pins,
  83        .npins  = ARRAY_SIZE(axp209_pins),
  84        .ldo_mask = BIT(0) | BIT(1),
  85        .adc_mask = BIT(0) | BIT(1),
  86        .gpio_status_offset = 4,
  87        .adc_mux = AXP20X_MUX_ADC,
  88};
  89
  90static const struct axp20x_pctrl_desc axp813_data = {
  91        .pins   = axp813_pins,
  92        .npins  = ARRAY_SIZE(axp813_pins),
  93        .ldo_mask = BIT(0) | BIT(1),
  94        .adc_mask = BIT(0),
  95        .gpio_status_offset = 0,
  96        .adc_mux = AXP813_MUX_ADC,
  97};
  98
  99static int axp20x_gpio_get_reg(unsigned int offset)
 100{
 101        switch (offset) {
 102        case 0:
 103                return AXP20X_GPIO0_CTRL;
 104        case 1:
 105                return AXP20X_GPIO1_CTRL;
 106        case 2:
 107                return AXP20X_GPIO2_CTRL;
 108        }
 109
 110        return -EINVAL;
 111}
 112
 113static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
 114{
 115        return pinctrl_gpio_direction_input(chip->base + offset);
 116}
 117
 118static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
 119{
 120        struct axp20x_pctl *pctl = gpiochip_get_data(chip);
 121        unsigned int val;
 122        int ret;
 123
 124        ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
 125        if (ret)
 126                return ret;
 127
 128        return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
 129}
 130
 131static int axp20x_gpio_get_direction(struct gpio_chip *chip,
 132                                     unsigned int offset)
 133{
 134        struct axp20x_pctl *pctl = gpiochip_get_data(chip);
 135        unsigned int val;
 136        int reg, ret;
 137
 138        reg = axp20x_gpio_get_reg(offset);
 139        if (reg < 0)
 140                return reg;
 141
 142        ret = regmap_read(pctl->regmap, reg, &val);
 143        if (ret)
 144                return ret;
 145
 146        /*
 147         * This shouldn't really happen if the pin is in use already,
 148         * or if it's not in use yet, it doesn't matter since we're
 149         * going to change the value soon anyway. Default to output.
 150         */
 151        if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
 152                return GPIO_LINE_DIRECTION_OUT;
 153
 154        /*
 155         * The GPIO directions are the three lowest values.
 156         * 2 is input, 0 and 1 are output
 157         */
 158        if (val & 2)
 159                return GPIO_LINE_DIRECTION_IN;
 160
 161        return GPIO_LINE_DIRECTION_OUT;
 162}
 163
 164static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
 165                              int value)
 166{
 167        chip->set(chip, offset, value);
 168
 169        return 0;
 170}
 171
 172static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
 173                            int value)
 174{
 175        struct axp20x_pctl *pctl = gpiochip_get_data(chip);
 176        int reg;
 177
 178        reg = axp20x_gpio_get_reg(offset);
 179        if (reg < 0)
 180                return;
 181
 182        regmap_update_bits(pctl->regmap, reg,
 183                           AXP20X_GPIO_FUNCTIONS,
 184                           value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
 185                           AXP20X_GPIO_FUNCTION_OUT_LOW);
 186}
 187
 188static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
 189                          u8 config)
 190{
 191        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 192        int reg;
 193
 194        reg = axp20x_gpio_get_reg(offset);
 195        if (reg < 0)
 196                return reg;
 197
 198        return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
 199                                  config);
 200}
 201
 202static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
 203{
 204        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 205
 206        return ARRAY_SIZE(pctl->funcs);
 207}
 208
 209static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
 210                                        unsigned int selector)
 211{
 212        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 213
 214        return pctl->funcs[selector].name;
 215}
 216
 217static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
 218                                  unsigned int selector,
 219                                  const char * const **groups,
 220                                  unsigned int *num_groups)
 221{
 222        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 223
 224        *groups = pctl->funcs[selector].groups;
 225        *num_groups = pctl->funcs[selector].ngroups;
 226
 227        return 0;
 228}
 229
 230static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
 231                              unsigned int function, unsigned int group)
 232{
 233        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 234        unsigned int mask;
 235
 236        /* Every pin supports GPIO_OUT and GPIO_IN functions */
 237        if (function <= AXP20X_FUNC_GPIO_IN)
 238                return axp20x_pmx_set(pctldev, group,
 239                                      pctl->funcs[function].muxval);
 240
 241        if (function == AXP20X_FUNC_LDO)
 242                mask = pctl->desc->ldo_mask;
 243        else
 244                mask = pctl->desc->adc_mask;
 245
 246        if (!(BIT(group) & mask))
 247                return -EINVAL;
 248
 249        /*
 250         * We let the regulator framework handle the LDO muxing as muxing bits
 251         * are basically also regulators on/off bits. It's better not to enforce
 252         * any state of the regulator when selecting LDO mux so that we don't
 253         * interfere with the regulator driver.
 254         */
 255        if (function == AXP20X_FUNC_LDO)
 256                return 0;
 257
 258        return axp20x_pmx_set(pctldev, group, pctl->funcs[function].muxval);
 259}
 260
 261static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
 262                                         struct pinctrl_gpio_range *range,
 263                                         unsigned int offset, bool input)
 264{
 265        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 266
 267        if (input)
 268                return axp20x_pmx_set(pctldev, offset,
 269                                      pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
 270
 271        return axp20x_pmx_set(pctldev, offset,
 272                              pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
 273}
 274
 275static const struct pinmux_ops axp20x_pmx_ops = {
 276        .get_functions_count    = axp20x_pmx_func_cnt,
 277        .get_function_name      = axp20x_pmx_func_name,
 278        .get_function_groups    = axp20x_pmx_func_groups,
 279        .set_mux                = axp20x_pmx_set_mux,
 280        .gpio_set_direction     = axp20x_pmx_gpio_set_direction,
 281        .strict                 = true,
 282};
 283
 284static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
 285{
 286        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 287
 288        return pctl->desc->npins;
 289}
 290
 291static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
 292                             const unsigned int **pins, unsigned int *num_pins)
 293{
 294        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 295
 296        *pins = (unsigned int *)&pctl->desc->pins[selector];
 297        *num_pins = 1;
 298
 299        return 0;
 300}
 301
 302static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
 303                                     unsigned int selector)
 304{
 305        struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
 306
 307        return pctl->desc->pins[selector].name;
 308}
 309
 310static const struct pinctrl_ops axp20x_pctrl_ops = {
 311        .dt_node_to_map         = pinconf_generic_dt_node_to_map_group,
 312        .dt_free_map            = pinconf_generic_dt_free_map,
 313        .get_groups_count       = axp20x_groups_cnt,
 314        .get_group_name         = axp20x_group_name,
 315        .get_group_pins         = axp20x_group_pins,
 316};
 317
 318static int axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
 319                                          unsigned int mask_len,
 320                                          struct axp20x_pinctrl_function *func,
 321                                          const struct pinctrl_pin_desc *pins)
 322{
 323        unsigned long int mask_cpy = mask;
 324        const char **group;
 325        unsigned int ngroups = hweight8(mask);
 326        int bit;
 327
 328        func->ngroups = ngroups;
 329        if (func->ngroups > 0) {
 330                func->groups = devm_kcalloc(dev,
 331                                            ngroups, sizeof(const char *),
 332                                            GFP_KERNEL);
 333                if (!func->groups)
 334                        return -ENOMEM;
 335                group = func->groups;
 336                for_each_set_bit(bit, &mask_cpy, mask_len) {
 337                        *group = pins[bit].name;
 338                        group++;
 339                }
 340        }
 341
 342        return 0;
 343}
 344
 345static int axp20x_build_funcs_groups(struct platform_device *pdev)
 346{
 347        struct axp20x_pctl *pctl = platform_get_drvdata(pdev);
 348        int i, ret, pin, npins = pctl->desc->npins;
 349
 350        pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
 351        pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
 352        pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
 353        pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
 354        pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
 355        /*
 356         * Muxval for LDO is useless as we won't use it.
 357         * See comment in axp20x_pmx_set_mux.
 358         */
 359        pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
 360        pctl->funcs[AXP20X_FUNC_ADC].muxval = pctl->desc->adc_mux;
 361
 362        /* Every pin supports GPIO_OUT and GPIO_IN functions */
 363        for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
 364                pctl->funcs[i].ngroups = npins;
 365                pctl->funcs[i].groups = devm_kcalloc(&pdev->dev,
 366                                                     npins, sizeof(char *),
 367                                                     GFP_KERNEL);
 368                if (!pctl->funcs[i].groups)
 369                        return -ENOMEM;
 370                for (pin = 0; pin < npins; pin++)
 371                        pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
 372        }
 373
 374        ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
 375                                      npins, &pctl->funcs[AXP20X_FUNC_LDO],
 376                                      pctl->desc->pins);
 377        if (ret)
 378                return ret;
 379
 380        ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
 381                                      npins, &pctl->funcs[AXP20X_FUNC_ADC],
 382                                      pctl->desc->pins);
 383        if (ret)
 384                return ret;
 385
 386        return 0;
 387}
 388
 389static const struct of_device_id axp20x_pctl_match[] = {
 390        { .compatible = "x-powers,axp209-gpio", .data = &axp20x_data, },
 391        { .compatible = "x-powers,axp813-gpio", .data = &axp813_data, },
 392        { }
 393};
 394MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
 395
 396static int axp20x_pctl_probe(struct platform_device *pdev)
 397{
 398        struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
 399        struct axp20x_pctl *pctl;
 400        struct device *dev = &pdev->dev;
 401        struct pinctrl_desc *pctrl_desc;
 402        int ret;
 403
 404        if (!of_device_is_available(pdev->dev.of_node))
 405                return -ENODEV;
 406
 407        if (!axp20x) {
 408                dev_err(&pdev->dev, "Parent drvdata not set\n");
 409                return -EINVAL;
 410        }
 411
 412        pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
 413        if (!pctl)
 414                return -ENOMEM;
 415
 416        pctl->chip.base                 = -1;
 417        pctl->chip.can_sleep            = true;
 418        pctl->chip.request              = gpiochip_generic_request;
 419        pctl->chip.free                 = gpiochip_generic_free;
 420        pctl->chip.parent               = &pdev->dev;
 421        pctl->chip.label                = dev_name(&pdev->dev);
 422        pctl->chip.owner                = THIS_MODULE;
 423        pctl->chip.get                  = axp20x_gpio_get;
 424        pctl->chip.get_direction        = axp20x_gpio_get_direction;
 425        pctl->chip.set                  = axp20x_gpio_set;
 426        pctl->chip.direction_input      = axp20x_gpio_input;
 427        pctl->chip.direction_output     = axp20x_gpio_output;
 428
 429        pctl->desc = of_device_get_match_data(dev);
 430
 431        pctl->chip.ngpio                = pctl->desc->npins;
 432
 433        pctl->regmap = axp20x->regmap;
 434        pctl->dev = &pdev->dev;
 435
 436        platform_set_drvdata(pdev, pctl);
 437
 438        ret = axp20x_build_funcs_groups(pdev);
 439        if (ret) {
 440                dev_err(&pdev->dev, "failed to build groups\n");
 441                return ret;
 442        }
 443
 444        pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
 445        if (!pctrl_desc)
 446                return -ENOMEM;
 447
 448        pctrl_desc->name = dev_name(&pdev->dev);
 449        pctrl_desc->owner = THIS_MODULE;
 450        pctrl_desc->pins = pctl->desc->pins;
 451        pctrl_desc->npins = pctl->desc->npins;
 452        pctrl_desc->pctlops = &axp20x_pctrl_ops;
 453        pctrl_desc->pmxops = &axp20x_pmx_ops;
 454
 455        pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
 456        if (IS_ERR(pctl->pctl_dev)) {
 457                dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
 458                return PTR_ERR(pctl->pctl_dev);
 459        }
 460
 461        ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
 462        if (ret) {
 463                dev_err(&pdev->dev, "Failed to register GPIO chip\n");
 464                return ret;
 465        }
 466
 467        ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
 468                                     pctl->desc->pins->number,
 469                                     pctl->desc->pins->number,
 470                                     pctl->desc->npins);
 471        if (ret) {
 472                dev_err(&pdev->dev, "failed to add pin range\n");
 473                return ret;
 474        }
 475
 476        dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
 477
 478        return 0;
 479}
 480
 481static struct platform_driver axp20x_pctl_driver = {
 482        .probe          = axp20x_pctl_probe,
 483        .driver = {
 484                .name           = "axp20x-gpio",
 485                .of_match_table = axp20x_pctl_match,
 486        },
 487};
 488
 489module_platform_driver(axp20x_pctl_driver);
 490
 491MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 492MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
 493MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
 494MODULE_LICENSE("GPL");
 495