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 int wm831x_gpio_set(struct gpio_chip *chip, unsigned int offset, 62 int value) 63 { 64 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 65 struct wm831x *wm831x = wm831x_gpio->wm831x; 66 67 return wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset, 68 value << offset); 69 } 70 71 static int wm831x_gpio_direction_out(struct gpio_chip *chip, 72 unsigned offset, int value) 73 { 74 struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip); 75 struct wm831x *wm831x = wm831x_gpio->wm831x; 76 int val = 0; 77 int ret; 78 79 if (wm831x->has_gpio_ena) 80 val |= WM831X_GPN_TRI; 81 82 ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset, 83 WM831X_GPN_DIR | WM831X_GPN_TRI | 84 WM831X_GPN_FN_MASK, val); 85 if (ret < 0) 86 return ret; 87 88 /* Can only set GPIO state once it's in output mode */ 89 return wm831x_gpio_set(chip, offset, value); 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 reg; 163 const char *pull, *powerdomain; 164 165 /* We report the GPIO even if it's not requested since 166 * we're also reporting things like alternate 167 * functions which apply even when the GPIO is not in 168 * use as a GPIO. 169 */ 170 char *label __free(kfree) = gpiochip_dup_line_label(chip, i); 171 if (IS_ERR(label)) { 172 dev_err(wm831x->dev, "Failed to duplicate label\n"); 173 continue; 174 } 175 176 seq_printf(s, " gpio-%-3d (%-20.20s) ", 177 i, label ?: "Unrequested"); 178 179 reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i); 180 if (reg < 0) { 181 dev_err(wm831x->dev, 182 "GPIO control %d read failed: %d\n", 183 i, reg); 184 seq_putc(s, '\n'); 185 continue; 186 } 187 188 switch (reg & WM831X_GPN_PULL_MASK) { 189 case WM831X_GPIO_PULL_NONE: 190 pull = "nopull"; 191 break; 192 case WM831X_GPIO_PULL_DOWN: 193 pull = "pulldown"; 194 break; 195 case WM831X_GPIO_PULL_UP: 196 pull = "pullup"; 197 break; 198 default: 199 pull = "INVALID PULL"; 200 break; 201 } 202 203 switch (i + 1) { 204 case 1 ... 3: 205 case 7 ... 9: 206 if (reg & WM831X_GPN_PWR_DOM) 207 powerdomain = "VPMIC"; 208 else 209 powerdomain = "DBVDD"; 210 break; 211 212 case 4 ... 6: 213 case 10 ... 12: 214 if (reg & WM831X_GPN_PWR_DOM) 215 powerdomain = "SYSVDD"; 216 else 217 powerdomain = "DBVDD"; 218 break; 219 220 case 13 ... 16: 221 powerdomain = "TPVDD"; 222 break; 223 224 default: 225 BUG(); 226 break; 227 } 228 229 tristated = reg & WM831X_GPN_TRI; 230 if (wm831x->has_gpio_ena) 231 tristated = !tristated; 232 233 seq_printf(s, " %s %s %s %s%s\n" 234 " %s%s (0x%4x)\n", 235 reg & WM831X_GPN_DIR ? "in" : "out", 236 str_high_low(wm831x_gpio_get(chip, i)), 237 pull, 238 powerdomain, 239 reg & WM831X_GPN_POL ? "" : " inverted", 240 reg & WM831X_GPN_OD ? "open-drain" : "push-pull", 241 tristated ? " tristated" : "", 242 reg); 243 } 244 } 245 #else 246 #define wm831x_gpio_dbg_show NULL 247 #endif 248 249 static const struct gpio_chip template_chip = { 250 .label = "wm831x", 251 .owner = THIS_MODULE, 252 .direction_input = wm831x_gpio_direction_in, 253 .get = wm831x_gpio_get, 254 .direction_output = wm831x_gpio_direction_out, 255 .set = wm831x_gpio_set, 256 .to_irq = wm831x_gpio_to_irq, 257 .set_config = wm831x_set_config, 258 .dbg_show = wm831x_gpio_dbg_show, 259 .can_sleep = true, 260 }; 261 262 static int wm831x_gpio_probe(struct platform_device *pdev) 263 { 264 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 265 struct wm831x_pdata *pdata = &wm831x->pdata; 266 struct wm831x_gpio *wm831x_gpio; 267 268 device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent)); 269 270 wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio), 271 GFP_KERNEL); 272 if (wm831x_gpio == NULL) 273 return -ENOMEM; 274 275 wm831x_gpio->wm831x = wm831x; 276 wm831x_gpio->gpio_chip = template_chip; 277 wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio; 278 wm831x_gpio->gpio_chip.parent = &pdev->dev; 279 if (pdata && pdata->gpio_base) 280 wm831x_gpio->gpio_chip.base = pdata->gpio_base; 281 else 282 wm831x_gpio->gpio_chip.base = -1; 283 284 return devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip, wm831x_gpio); 285 } 286 287 static struct platform_driver wm831x_gpio_driver = { 288 .driver.name = "wm831x-gpio", 289 .probe = wm831x_gpio_probe, 290 }; 291 292 static int __init wm831x_gpio_init(void) 293 { 294 return platform_driver_register(&wm831x_gpio_driver); 295 } 296 subsys_initcall(wm831x_gpio_init); 297 298 static void __exit wm831x_gpio_exit(void) 299 { 300 platform_driver_unregister(&wm831x_gpio_driver); 301 } 302 module_exit(wm831x_gpio_exit); 303 304 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 305 MODULE_DESCRIPTION("GPIO interface for WM831x PMICs"); 306 MODULE_LICENSE("GPL"); 307 MODULE_ALIAS("platform:wm831x-gpio"); 308