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1// SPDX-License-Identifier: GPL-2.0+2/*3 * gpiolib support for Wolfson WM831x PMICs4 *5 * Copyright 2009 Wolfson Microelectronics PLC.6 *7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>8 *9 */10 11#include <linux/cleanup.h>12#include <linux/kernel.h>13#include <linux/slab.h>14#include <linux/module.h>15#include <linux/gpio/driver.h>16#include <linux/mfd/core.h>17#include <linux/platform_device.h>18#include <linux/seq_file.h>19 20#include <linux/mfd/wm831x/core.h>21#include <linux/mfd/wm831x/pdata.h>22#include <linux/mfd/wm831x/gpio.h>23#include <linux/mfd/wm831x/irq.h>24 25struct wm831x_gpio {26 struct wm831x *wm831x;27 struct gpio_chip gpio_chip;28};29 30static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)31{32 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);33 struct wm831x *wm831x = wm831x_gpio->wm831x;34 int val = WM831X_GPN_DIR;35 36 if (wm831x->has_gpio_ena)37 val |= WM831X_GPN_TRI;38 39 return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,40 WM831X_GPN_DIR | WM831X_GPN_TRI |41 WM831X_GPN_FN_MASK, val);42}43 44static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)45{46 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);47 struct wm831x *wm831x = wm831x_gpio->wm831x;48 int ret;49 50 ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);51 if (ret < 0)52 return ret;53 54 if (ret & 1 << offset)55 return 1;56 else57 return 0;58}59 60static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)61{62 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);63 struct wm831x *wm831x = wm831x_gpio->wm831x;64 65 wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,66 value << offset);67}68 69static int wm831x_gpio_direction_out(struct gpio_chip *chip,70 unsigned offset, int value)71{72 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);73 struct wm831x *wm831x = wm831x_gpio->wm831x;74 int val = 0;75 int ret;76 77 if (wm831x->has_gpio_ena)78 val |= WM831X_GPN_TRI;79 80 ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,81 WM831X_GPN_DIR | WM831X_GPN_TRI |82 WM831X_GPN_FN_MASK, val);83 if (ret < 0)84 return ret;85 86 /* Can only set GPIO state once it's in output mode */87 wm831x_gpio_set(chip, offset, value);88 89 return 0;90}91 92static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)93{94 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);95 struct wm831x *wm831x = wm831x_gpio->wm831x;96 97 return irq_create_mapping(wm831x->irq_domain,98 WM831X_IRQ_GPIO_1 + offset);99}100 101static int wm831x_gpio_set_debounce(struct wm831x *wm831x, unsigned offset,102 unsigned debounce)103{104 int reg = WM831X_GPIO1_CONTROL + offset;105 int ret, fn;106 107 ret = wm831x_reg_read(wm831x, reg);108 if (ret < 0)109 return ret;110 111 switch (ret & WM831X_GPN_FN_MASK) {112 case 0:113 case 1:114 break;115 default:116 /* Not in GPIO mode */117 return -EBUSY;118 }119 120 if (debounce >= 32 && debounce <= 64)121 fn = 0;122 else if (debounce >= 4000 && debounce <= 8000)123 fn = 1;124 else125 return -EINVAL;126 127 return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);128}129 130static int wm831x_set_config(struct gpio_chip *chip, unsigned int offset,131 unsigned long config)132{133 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);134 struct wm831x *wm831x = wm831x_gpio->wm831x;135 int reg = WM831X_GPIO1_CONTROL + offset;136 137 switch (pinconf_to_config_param(config)) {138 case PIN_CONFIG_DRIVE_OPEN_DRAIN:139 return wm831x_set_bits(wm831x, reg,140 WM831X_GPN_OD_MASK, WM831X_GPN_OD);141 case PIN_CONFIG_DRIVE_PUSH_PULL:142 return wm831x_set_bits(wm831x, reg,143 WM831X_GPN_OD_MASK, 0);144 case PIN_CONFIG_INPUT_DEBOUNCE:145 return wm831x_gpio_set_debounce(wm831x, offset,146 pinconf_to_config_argument(config));147 default:148 break;149 }150 151 return -ENOTSUPP;152}153 154#ifdef CONFIG_DEBUG_FS155static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)156{157 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);158 struct wm831x *wm831x = wm831x_gpio->wm831x;159 int i, tristated;160 161 for (i = 0; i < chip->ngpio; i++) {162 int gpio = i + chip->base;163 int reg;164 const char *pull, *powerdomain;165 166 /* We report the GPIO even if it's not requested since167 * we're also reporting things like alternate168 * functions which apply even when the GPIO is not in169 * use as a GPIO.170 */171 char *label __free(kfree) = gpiochip_dup_line_label(chip, i);172 if (IS_ERR(label)) {173 dev_err(wm831x->dev, "Failed to duplicate label\n");174 continue;175 }176 177 seq_printf(s, " gpio-%-3d (%-20.20s) ",178 gpio, label ?: "Unrequested");179 180 reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);181 if (reg < 0) {182 dev_err(wm831x->dev,183 "GPIO control %d read failed: %d\n",184 gpio, reg);185 seq_putc(s, '\n');186 continue;187 }188 189 switch (reg & WM831X_GPN_PULL_MASK) {190 case WM831X_GPIO_PULL_NONE:191 pull = "nopull";192 break;193 case WM831X_GPIO_PULL_DOWN:194 pull = "pulldown";195 break;196 case WM831X_GPIO_PULL_UP:197 pull = "pullup";198 break;199 default:200 pull = "INVALID PULL";201 break;202 }203 204 switch (i + 1) {205 case 1 ... 3:206 case 7 ... 9:207 if (reg & WM831X_GPN_PWR_DOM)208 powerdomain = "VPMIC";209 else210 powerdomain = "DBVDD";211 break;212 213 case 4 ... 6:214 case 10 ... 12:215 if (reg & WM831X_GPN_PWR_DOM)216 powerdomain = "SYSVDD";217 else218 powerdomain = "DBVDD";219 break;220 221 case 13 ... 16:222 powerdomain = "TPVDD";223 break;224 225 default:226 BUG();227 break;228 }229 230 tristated = reg & WM831X_GPN_TRI;231 if (wm831x->has_gpio_ena)232 tristated = !tristated;233 234 seq_printf(s, " %s %s %s %s%s\n"235 " %s%s (0x%4x)\n",236 reg & WM831X_GPN_DIR ? "in" : "out",237 wm831x_gpio_get(chip, i) ? "high" : "low",238 pull,239 powerdomain,240 reg & WM831X_GPN_POL ? "" : " inverted",241 reg & WM831X_GPN_OD ? "open-drain" : "push-pull",242 tristated ? " tristated" : "",243 reg);244 }245}246#else247#define wm831x_gpio_dbg_show NULL248#endif249 250static const struct gpio_chip template_chip = {251 .label = "wm831x",252 .owner = THIS_MODULE,253 .direction_input = wm831x_gpio_direction_in,254 .get = wm831x_gpio_get,255 .direction_output = wm831x_gpio_direction_out,256 .set = wm831x_gpio_set,257 .to_irq = wm831x_gpio_to_irq,258 .set_config = wm831x_set_config,259 .dbg_show = wm831x_gpio_dbg_show,260 .can_sleep = true,261};262 263static int wm831x_gpio_probe(struct platform_device *pdev)264{265 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);266 struct wm831x_pdata *pdata = &wm831x->pdata;267 struct wm831x_gpio *wm831x_gpio;268 269 device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));270 271 wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),272 GFP_KERNEL);273 if (wm831x_gpio == NULL)274 return -ENOMEM;275 276 wm831x_gpio->wm831x = wm831x;277 wm831x_gpio->gpio_chip = template_chip;278 wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;279 wm831x_gpio->gpio_chip.parent = &pdev->dev;280 if (pdata && pdata->gpio_base)281 wm831x_gpio->gpio_chip.base = pdata->gpio_base;282 else283 wm831x_gpio->gpio_chip.base = -1;284 285 return devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip, wm831x_gpio);286}287 288static struct platform_driver wm831x_gpio_driver = {289 .driver.name = "wm831x-gpio",290 .probe = wm831x_gpio_probe,291};292 293static int __init wm831x_gpio_init(void)294{295 return platform_driver_register(&wm831x_gpio_driver);296}297subsys_initcall(wm831x_gpio_init);298 299static void __exit wm831x_gpio_exit(void)300{301 platform_driver_unregister(&wm831x_gpio_driver);302}303module_exit(wm831x_gpio_exit);304 305MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");306MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");307MODULE_LICENSE("GPL");308MODULE_ALIAS("platform:wm831x-gpio");309