1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * gpiolib support for Wolfson WM831x PMICs 4 * 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 #include <linux/string_choices.h> 20 21 #include <linux/mfd/wm831x/core.h> 22 #include <linux/mfd/wm831x/pdata.h> 23 #include <linux/mfd/wm831x/gpio.h> 24 #include <linux/mfd/wm831x/irq.h> 25 26 struct wm831x_gpio { 27 struct wm831x *wm831x; 28 struct gpio_chip gpio_chip; 29 }; 30 31 static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset) 32 { 33 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 34 struct wm831x *wm831x = wm831x_gpio->wm831x; 35 int val = WM831X_GPN_DIR; 36 37 if (wm831x->has_gpio_ena) 38 val |= WM831X_GPN_TRI; 39 40 return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset, 41 WM831X_GPN_DIR | WM831X_GPN_TRI | 42 WM831X_GPN_FN_MASK, val); 43 } 44 45 static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset) 46 { 47 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 48 struct wm831x *wm831x = wm831x_gpio->wm831x; 49 int ret; 50 51 ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL); 52 if (ret < 0) 53 return ret; 54 55 if (ret & 1 << offset) 56 return 1; 57 else 58 return 0; 59 } 60 61 static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 62 { 63 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 64 struct wm831x *wm831x = wm831x_gpio->wm831x; 65 66 wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset, 67 value << offset); 68 } 69 70 static int wm831x_gpio_direction_out(struct gpio_chip *chip, 71 unsigned offset, int value) 72 { 73 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 74 struct wm831x *wm831x = wm831x_gpio->wm831x; 75 int val = 0; 76 int ret; 77 78 if (wm831x->has_gpio_ena) 79 val |= WM831X_GPN_TRI; 80 81 ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset, 82 WM831X_GPN_DIR | WM831X_GPN_TRI | 83 WM831X_GPN_FN_MASK, val); 84 if (ret < 0) 85 return ret; 86 87 /* Can only set GPIO state once it's in output mode */ 88 wm831x_gpio_set(chip, offset, value); 89 90 return 0; 91 } 92 93 static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 94 { 95 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 96 struct wm831x *wm831x = wm831x_gpio->wm831x; 97 98 return irq_create_mapping(wm831x->irq_domain, 99 WM831X_IRQ_GPIO_1 + offset); 100 } 101 102 static int wm831x_gpio_set_debounce(struct wm831x *wm831x, unsigned offset, 103 unsigned debounce) 104 { 105 int reg = WM831X_GPIO1_CONTROL + offset; 106 int ret, fn; 107 108 ret = wm831x_reg_read(wm831x, reg); 109 if (ret < 0) 110 return ret; 111 112 switch (ret & WM831X_GPN_FN_MASK) { 113 case 0: 114 case 1: 115 break; 116 default: 117 /* Not in GPIO mode */ 118 return -EBUSY; 119 } 120 121 if (debounce >= 32 && debounce <= 64) 122 fn = 0; 123 else if (debounce >= 4000 && debounce <= 8000) 124 fn = 1; 125 else 126 return -EINVAL; 127 128 return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn); 129 } 130 131 static int wm831x_set_config(struct gpio_chip *chip, unsigned int offset, 132 unsigned long config) 133 { 134 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 135 struct wm831x *wm831x = wm831x_gpio->wm831x; 136 int reg = WM831X_GPIO1_CONTROL + offset; 137 138 switch (pinconf_to_config_param(config)) { 139 case PIN_CONFIG_DRIVE_OPEN_DRAIN: 140 return wm831x_set_bits(wm831x, reg, 141 WM831X_GPN_OD_MASK, WM831X_GPN_OD); 142 case PIN_CONFIG_DRIVE_PUSH_PULL: 143 return wm831x_set_bits(wm831x, reg, 144 WM831X_GPN_OD_MASK, 0); 145 case PIN_CONFIG_INPUT_DEBOUNCE: 146 return wm831x_gpio_set_debounce(wm831x, offset, 147 pinconf_to_config_argument(config)); 148 default: 149 break; 150 } 151 152 return -ENOTSUPP; 153 } 154 155 #ifdef CONFIG_DEBUG_FS 156 static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) 157 { 158 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 159 struct wm831x *wm831x = wm831x_gpio->wm831x; 160 int i, tristated; 161 162 for (i = 0; i < chip->ngpio; i++) { 163 int gpio = i + chip->base; 164 int reg; 165 const char *pull, *powerdomain; 166 167 /* We report the GPIO even if it's not requested since 168 * we're also reporting things like alternate 169 * functions which apply even when the GPIO is not in 170 * use as a GPIO. 171 */ 172 char *label __free(kfree) = gpiochip_dup_line_label(chip, i); 173 if (IS_ERR(label)) { 174 dev_err(wm831x->dev, "Failed to duplicate label\n"); 175 continue; 176 } 177 178 seq_printf(s, " gpio-%-3d (%-20.20s) ", 179 gpio, label ?: "Unrequested"); 180 181 reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i); 182 if (reg < 0) { 183 dev_err(wm831x->dev, 184 "GPIO control %d read failed: %d\n", 185 gpio, reg); 186 seq_putc(s, '\n'); 187 continue; 188 } 189 190 switch (reg & WM831X_GPN_PULL_MASK) { 191 case WM831X_GPIO_PULL_NONE: 192 pull = "nopull"; 193 break; 194 case WM831X_GPIO_PULL_DOWN: 195 pull = "pulldown"; 196 break; 197 case WM831X_GPIO_PULL_UP: 198 pull = "pullup"; 199 break; 200 default: 201 pull = "INVALID PULL"; 202 break; 203 } 204 205 switch (i + 1) { 206 case 1 ... 3: 207 case 7 ... 9: 208 if (reg & WM831X_GPN_PWR_DOM) 209 powerdomain = "VPMIC"; 210 else 211 powerdomain = "DBVDD"; 212 break; 213 214 case 4 ... 6: 215 case 10 ... 12: 216 if (reg & WM831X_GPN_PWR_DOM) 217 powerdomain = "SYSVDD"; 218 else 219 powerdomain = "DBVDD"; 220 break; 221 222 case 13 ... 16: 223 powerdomain = "TPVDD"; 224 break; 225 226 default: 227 BUG(); 228 break; 229 } 230 231 tristated = reg & WM831X_GPN_TRI; 232 if (wm831x->has_gpio_ena) 233 tristated = !tristated; 234 235 seq_printf(s, " %s %s %s %s%s\n" 236 " %s%s (0x%4x)\n", 237 reg & WM831X_GPN_DIR ? "in" : "out", 238 str_high_low(wm831x_gpio_get(chip, i)), 239 pull, 240 powerdomain, 241 reg & WM831X_GPN_POL ? "" : " inverted", 242 reg & WM831X_GPN_OD ? "open-drain" : "push-pull", 243 tristated ? " tristated" : "", 244 reg); 245 } 246 } 247 #else 248 #define wm831x_gpio_dbg_show NULL 249 #endif 250 251 static const struct gpio_chip template_chip = { 252 .label = "wm831x", 253 .owner = THIS_MODULE, 254 .direction_input = wm831x_gpio_direction_in, 255 .get = wm831x_gpio_get, 256 .direction_output = wm831x_gpio_direction_out, 257 .set = wm831x_gpio_set, 258 .to_irq = wm831x_gpio_to_irq, 259 .set_config = wm831x_set_config, 260 .dbg_show = wm831x_gpio_dbg_show, 261 .can_sleep = true, 262 }; 263 264 static int wm831x_gpio_probe(struct platform_device *pdev) 265 { 266 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 267 struct wm831x_pdata *pdata = &wm831x->pdata; 268 struct wm831x_gpio *wm831x_gpio; 269 270 device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent)); 271 272 wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio), 273 GFP_KERNEL); 274 if (wm831x_gpio == NULL) 275 return -ENOMEM; 276 277 wm831x_gpio->wm831x = wm831x; 278 wm831x_gpio->gpio_chip = template_chip; 279 wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio; 280 wm831x_gpio->gpio_chip.parent = &pdev->dev; 281 if (pdata && pdata->gpio_base) 282 wm831x_gpio->gpio_chip.base = pdata->gpio_base; 283 else 284 wm831x_gpio->gpio_chip.base = -1; 285 286 return devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip, wm831x_gpio); 287 } 288 289 static struct platform_driver wm831x_gpio_driver = { 290 .driver.name = "wm831x-gpio", 291 .probe = wm831x_gpio_probe, 292 }; 293 294 static int __init wm831x_gpio_init(void) 295 { 296 return platform_driver_register(&wm831x_gpio_driver); 297 } 298 subsys_initcall(wm831x_gpio_init); 299 300 static void __exit wm831x_gpio_exit(void) 301 { 302 platform_driver_unregister(&wm831x_gpio_driver); 303 } 304 module_exit(wm831x_gpio_exit); 305 306 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 307 MODULE_DESCRIPTION("GPIO interface for WM831x PMICs"); 308 MODULE_LICENSE("GPL"); 309 MODULE_ALIAS("platform:wm831x-gpio"); 310