drivers/pinctrl/pinctrl-axp209.c

   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
  43 struct 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
  54 struct axp20x_pinctrl_function {
  55         const char      *name;
  56         unsigned int    muxval;
  57         const char      **groups;
  58         unsigned int    ngroups;
  59 };
  60
  61 struct 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
  70 static const struct pinctrl_pin_desc axp209_pins[] = {
  71         PINCTRL_PIN(0, "GPIO0"),
  72         PINCTRL_PIN(1, "GPIO1"),
  73         PINCTRL_PIN(2, "GPIO2"),
  74 };
  75
  76 static const struct pinctrl_pin_desc axp813_pins[] = {
  77         PINCTRL_PIN(0, "GPIO0"),
  78         PINCTRL_PIN(1, "GPIO1"),
  79 };
  80
  81 static 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
  90 static 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
  99 static 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
 113 static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
 114 {
 115         return pinctrl_gpio_direction_input(chip->base + offset);
 116 }
 117
 118 static 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
 131 static 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
 164 static 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
 172 static 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
 188 static 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
 202 static 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
 209 static 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
 217 static 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
 230 static 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
 261 static 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
 275 static 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
 284 static 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
 291 static 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
 302 static 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
 310 static 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
 318 static 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
 345 static 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
 389 static 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 };
 394 MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
 395
 396 static 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
 481 static 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
 489 module_platform_driver(axp20x_pctl_driver);
 490
 491 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 492 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
 493 MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
 494 MODULE_LICENSE("GPL");