1 /* 2 * gpiolib support for Wolfson WM8994 3 * 4 * Copyright 2009 Wolfson Microelectronics PLC. 5 * 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 * 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/slab.h> 17 #include <linux/module.h> 18 #include <linux/gpio.h> 19 #include <linux/mfd/core.h> 20 #include <linux/platform_device.h> 21 #include <linux/seq_file.h> 22 #include <linux/regmap.h> 23 24 #include <linux/mfd/wm8994/core.h> 25 #include <linux/mfd/wm8994/pdata.h> 26 #include <linux/mfd/wm8994/gpio.h> 27 #include <linux/mfd/wm8994/registers.h> 28 29 struct wm8994_gpio { 30 struct wm8994 *wm8994; 31 struct gpio_chip gpio_chip; 32 }; 33 34 static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip) 35 { 36 return container_of(chip, struct wm8994_gpio, gpio_chip); 37 } 38 39 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset) 40 { 41 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 42 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 43 44 switch (wm8994->type) { 45 case WM8958: 46 switch (offset) { 47 case 1: 48 case 2: 49 case 3: 50 case 4: 51 case 6: 52 return -EINVAL; 53 } 54 break; 55 default: 56 break; 57 } 58 59 return 0; 60 } 61 62 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset) 63 { 64 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 65 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 66 67 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, 68 WM8994_GPN_DIR, WM8994_GPN_DIR); 69 } 70 71 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset) 72 { 73 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 74 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 75 int ret; 76 77 ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset); 78 if (ret < 0) 79 return ret; 80 81 if (ret & WM8994_GPN_LVL) 82 return 1; 83 else 84 return 0; 85 } 86 87 static int wm8994_gpio_direction_out(struct gpio_chip *chip, 88 unsigned offset, int value) 89 { 90 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 91 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 92 93 if (value) 94 value = WM8994_GPN_LVL; 95 96 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, 97 WM8994_GPN_DIR | WM8994_GPN_LVL, value); 98 } 99 100 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 101 { 102 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 103 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 104 105 if (value) 106 value = WM8994_GPN_LVL; 107 108 wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value); 109 } 110 111 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 112 { 113 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 114 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 115 116 return regmap_irq_get_virq(wm8994->irq_data, offset); 117 } 118 119 120 #ifdef CONFIG_DEBUG_FS 121 static const char *wm8994_gpio_fn(u16 fn) 122 { 123 switch (fn) { 124 case WM8994_GP_FN_PIN_SPECIFIC: 125 return "pin-specific"; 126 case WM8994_GP_FN_GPIO: 127 return "GPIO"; 128 case WM8994_GP_FN_SDOUT: 129 return "SDOUT"; 130 case WM8994_GP_FN_IRQ: 131 return "IRQ"; 132 case WM8994_GP_FN_TEMPERATURE: 133 return "Temperature"; 134 case WM8994_GP_FN_MICBIAS1_DET: 135 return "MICBIAS1 detect"; 136 case WM8994_GP_FN_MICBIAS1_SHORT: 137 return "MICBIAS1 short"; 138 case WM8994_GP_FN_MICBIAS2_DET: 139 return "MICBIAS2 detect"; 140 case WM8994_GP_FN_MICBIAS2_SHORT: 141 return "MICBIAS2 short"; 142 case WM8994_GP_FN_FLL1_LOCK: 143 return "FLL1 lock"; 144 case WM8994_GP_FN_FLL2_LOCK: 145 return "FLL2 lock"; 146 case WM8994_GP_FN_SRC1_LOCK: 147 return "SRC1 lock"; 148 case WM8994_GP_FN_SRC2_LOCK: 149 return "SRC2 lock"; 150 case WM8994_GP_FN_DRC1_ACT: 151 return "DRC1 activity"; 152 case WM8994_GP_FN_DRC2_ACT: 153 return "DRC2 activity"; 154 case WM8994_GP_FN_DRC3_ACT: 155 return "DRC3 activity"; 156 case WM8994_GP_FN_WSEQ_STATUS: 157 return "Write sequencer"; 158 case WM8994_GP_FN_FIFO_ERROR: 159 return "FIFO error"; 160 case WM8994_GP_FN_OPCLK: 161 return "OPCLK"; 162 case WM8994_GP_FN_THW: 163 return "Thermal warning"; 164 case WM8994_GP_FN_DCS_DONE: 165 return "DC servo"; 166 case WM8994_GP_FN_FLL1_OUT: 167 return "FLL1 output"; 168 case WM8994_GP_FN_FLL2_OUT: 169 return "FLL1 output"; 170 default: 171 return "Unknown"; 172 } 173 } 174 175 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) 176 { 177 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 178 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 179 int i; 180 181 for (i = 0; i < chip->ngpio; i++) { 182 int gpio = i + chip->base; 183 int reg; 184 const char *label; 185 186 /* We report the GPIO even if it's not requested since 187 * we're also reporting things like alternate 188 * functions which apply even when the GPIO is not in 189 * use as a GPIO. 190 */ 191 label = gpiochip_is_requested(chip, i); 192 if (!label) 193 label = "Unrequested"; 194 195 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); 196 197 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i); 198 if (reg < 0) { 199 dev_err(wm8994->dev, 200 "GPIO control %d read failed: %d\n", 201 gpio, reg); 202 seq_printf(s, "\n"); 203 continue; 204 } 205 206 if (reg & WM8994_GPN_DIR) 207 seq_printf(s, "in "); 208 else 209 seq_printf(s, "out "); 210 211 if (reg & WM8994_GPN_PU) 212 seq_printf(s, "pull up "); 213 214 if (reg & WM8994_GPN_PD) 215 seq_printf(s, "pull down "); 216 217 if (reg & WM8994_GPN_POL) 218 seq_printf(s, "inverted "); 219 else 220 seq_printf(s, "noninverted "); 221 222 if (reg & WM8994_GPN_OP_CFG) 223 seq_printf(s, "open drain "); 224 else 225 seq_printf(s, "CMOS "); 226 227 seq_printf(s, "%s (%x)\n", 228 wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg); 229 } 230 } 231 #else 232 #define wm8994_gpio_dbg_show NULL 233 #endif 234 235 static struct gpio_chip template_chip = { 236 .label = "wm8994", 237 .owner = THIS_MODULE, 238 .request = wm8994_gpio_request, 239 .direction_input = wm8994_gpio_direction_in, 240 .get = wm8994_gpio_get, 241 .direction_output = wm8994_gpio_direction_out, 242 .set = wm8994_gpio_set, 243 .to_irq = wm8994_gpio_to_irq, 244 .dbg_show = wm8994_gpio_dbg_show, 245 .can_sleep = 1, 246 }; 247 248 static int wm8994_gpio_probe(struct platform_device *pdev) 249 { 250 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); 251 struct wm8994_pdata *pdata = wm8994->dev->platform_data; 252 struct wm8994_gpio *wm8994_gpio; 253 int ret; 254 255 wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio), 256 GFP_KERNEL); 257 if (wm8994_gpio == NULL) 258 return -ENOMEM; 259 260 wm8994_gpio->wm8994 = wm8994; 261 wm8994_gpio->gpio_chip = template_chip; 262 wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX; 263 wm8994_gpio->gpio_chip.dev = &pdev->dev; 264 if (pdata && pdata->gpio_base) 265 wm8994_gpio->gpio_chip.base = pdata->gpio_base; 266 else 267 wm8994_gpio->gpio_chip.base = -1; 268 269 ret = gpiochip_add(&wm8994_gpio->gpio_chip); 270 if (ret < 0) { 271 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", 272 ret); 273 goto err; 274 } 275 276 platform_set_drvdata(pdev, wm8994_gpio); 277 278 return ret; 279 280 err: 281 return ret; 282 } 283 284 static int wm8994_gpio_remove(struct platform_device *pdev) 285 { 286 struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev); 287 288 return gpiochip_remove(&wm8994_gpio->gpio_chip); 289 } 290 291 static struct platform_driver wm8994_gpio_driver = { 292 .driver.name = "wm8994-gpio", 293 .driver.owner = THIS_MODULE, 294 .probe = wm8994_gpio_probe, 295 .remove = wm8994_gpio_remove, 296 }; 297 298 static int __init wm8994_gpio_init(void) 299 { 300 return platform_driver_register(&wm8994_gpio_driver); 301 } 302 subsys_initcall(wm8994_gpio_init); 303 304 static void __exit wm8994_gpio_exit(void) 305 { 306 platform_driver_unregister(&wm8994_gpio_driver); 307 } 308 module_exit(wm8994_gpio_exit); 309 310 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 311 MODULE_DESCRIPTION("GPIO interface for WM8994"); 312 MODULE_LICENSE("GPL"); 313 MODULE_ALIAS("platform:wm8994-gpio"); 314