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 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 25 struct wm831x_gpio { 26 struct wm831x *wm831x; 27 struct gpio_chip gpio_chip; 28 }; 29 30 static 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 44 static 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 else 57 return 0; 58 } 59 60 static 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 69 static 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 92 static 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 } 100 101 static 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 else 125 return -EINVAL; 126 127 return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn); 128 } 129 130 static 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_FS 155 static 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 since 167 * we're also reporting things like alternate 168 * functions which apply even when the GPIO is not in 169 * 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 else 210 powerdomain = "DBVDD"; 211 break; 212 213 case 4 ... 6: 214 case 10 ... 12: 215 if (reg & WM831X_GPN_PWR_DOM) 216 powerdomain = "SYSVDD"; 217 else 218 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 #else 247 #define wm831x_gpio_dbg_show NULL 248 #endif 249 250 static 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 }; 262 263 static 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 else 283 wm831x_gpio->gpio_chip.base = -1; 284 285 return devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip, wm831x_gpio); 286 } 287 288 static struct platform_driver wm831x_gpio_driver = { 289 .driver.name = "wm831x-gpio", 290 .probe = wm831x_gpio_probe, 291 }; 292 293 static int __init wm831x_gpio_init(void) 294 { 295 return platform_driver_register(&wm831x_gpio_driver); 296 } 297 subsys_initcall(wm831x_gpio_init); 298 299 static void __exit wm831x_gpio_exit(void) 300 { 301 platform_driver_unregister(&wm831x_gpio_driver); 302 } 303 module_exit(wm831x_gpio_exit); 304 305 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 306 MODULE_DESCRIPTION("GPIO interface for WM831x PMICs"); 307 MODULE_LICENSE("GPL"); 308 MODULE_ALIAS("platform:wm831x-gpio"); 309