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 23 #include <linux/mfd/wm8994/core.h> 24 #include <linux/mfd/wm8994/pdata.h> 25 #include <linux/mfd/wm8994/gpio.h> 26 #include <linux/mfd/wm8994/registers.h> 27 28 struct wm8994_gpio { 29 struct wm8994 *wm8994; 30 struct gpio_chip gpio_chip; 31 }; 32 33 static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip) 34 { 35 return container_of(chip, struct wm8994_gpio, gpio_chip); 36 } 37 38 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset) 39 { 40 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 41 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 42 43 switch (wm8994->type) { 44 case WM8958: 45 switch (offset) { 46 case 1: 47 case 2: 48 case 3: 49 case 4: 50 case 6: 51 return -EINVAL; 52 } 53 break; 54 default: 55 break; 56 } 57 58 return 0; 59 } 60 61 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset) 62 { 63 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 64 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 65 66 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, 67 WM8994_GPN_DIR, WM8994_GPN_DIR); 68 } 69 70 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset) 71 { 72 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 73 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 74 int ret; 75 76 ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset); 77 if (ret < 0) 78 return ret; 79 80 if (ret & WM8994_GPN_LVL) 81 return 1; 82 else 83 return 0; 84 } 85 86 static int wm8994_gpio_direction_out(struct gpio_chip *chip, 87 unsigned offset, int value) 88 { 89 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 90 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 91 92 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, 93 WM8994_GPN_DIR, 0); 94 } 95 96 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 97 { 98 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 99 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 100 101 if (value) 102 value = WM8994_GPN_LVL; 103 104 wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value); 105 } 106 107 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 108 { 109 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 110 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 111 112 if (!wm8994->irq_base) 113 return -EINVAL; 114 115 return wm8994->irq_base + offset; 116 } 117 118 119 #ifdef CONFIG_DEBUG_FS 120 static const char *wm8994_gpio_fn(u16 fn) 121 { 122 switch (fn) { 123 case WM8994_GP_FN_PIN_SPECIFIC: 124 return "pin-specific"; 125 case WM8994_GP_FN_GPIO: 126 return "GPIO"; 127 case WM8994_GP_FN_SDOUT: 128 return "SDOUT"; 129 case WM8994_GP_FN_IRQ: 130 return "IRQ"; 131 case WM8994_GP_FN_TEMPERATURE: 132 return "Temperature"; 133 case WM8994_GP_FN_MICBIAS1_DET: 134 return "MICBIAS1 detect"; 135 case WM8994_GP_FN_MICBIAS1_SHORT: 136 return "MICBIAS1 short"; 137 case WM8994_GP_FN_MICBIAS2_DET: 138 return "MICBIAS2 detect"; 139 case WM8994_GP_FN_MICBIAS2_SHORT: 140 return "MICBIAS2 short"; 141 case WM8994_GP_FN_FLL1_LOCK: 142 return "FLL1 lock"; 143 case WM8994_GP_FN_FLL2_LOCK: 144 return "FLL2 lock"; 145 case WM8994_GP_FN_SRC1_LOCK: 146 return "SRC1 lock"; 147 case WM8994_GP_FN_SRC2_LOCK: 148 return "SRC2 lock"; 149 case WM8994_GP_FN_DRC1_ACT: 150 return "DRC1 activity"; 151 case WM8994_GP_FN_DRC2_ACT: 152 return "DRC2 activity"; 153 case WM8994_GP_FN_DRC3_ACT: 154 return "DRC3 activity"; 155 case WM8994_GP_FN_WSEQ_STATUS: 156 return "Write sequencer"; 157 case WM8994_GP_FN_FIFO_ERROR: 158 return "FIFO error"; 159 case WM8994_GP_FN_OPCLK: 160 return "OPCLK"; 161 case WM8994_GP_FN_THW: 162 return "Thermal warning"; 163 case WM8994_GP_FN_DCS_DONE: 164 return "DC servo"; 165 case WM8994_GP_FN_FLL1_OUT: 166 return "FLL1 output"; 167 case WM8994_GP_FN_FLL2_OUT: 168 return "FLL1 output"; 169 default: 170 return "Unknown"; 171 } 172 } 173 174 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) 175 { 176 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); 177 struct wm8994 *wm8994 = wm8994_gpio->wm8994; 178 int i; 179 180 for (i = 0; i < chip->ngpio; i++) { 181 int gpio = i + chip->base; 182 int reg; 183 const char *label; 184 185 /* We report the GPIO even if it's not requested since 186 * we're also reporting things like alternate 187 * functions which apply even when the GPIO is not in 188 * use as a GPIO. 189 */ 190 label = gpiochip_is_requested(chip, i); 191 if (!label) 192 label = "Unrequested"; 193 194 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); 195 196 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i); 197 if (reg < 0) { 198 dev_err(wm8994->dev, 199 "GPIO control %d read failed: %d\n", 200 gpio, reg); 201 seq_printf(s, "\n"); 202 continue; 203 } 204 205 if (reg & WM8994_GPN_DIR) 206 seq_printf(s, "in "); 207 else 208 seq_printf(s, "out "); 209 210 if (reg & WM8994_GPN_PU) 211 seq_printf(s, "pull up "); 212 213 if (reg & WM8994_GPN_PD) 214 seq_printf(s, "pull down "); 215 216 if (reg & WM8994_GPN_POL) 217 seq_printf(s, "inverted "); 218 else 219 seq_printf(s, "noninverted "); 220 221 if (reg & WM8994_GPN_OP_CFG) 222 seq_printf(s, "open drain "); 223 else 224 seq_printf(s, "CMOS "); 225 226 seq_printf(s, "%s (%x)\n", 227 wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg); 228 } 229 } 230 #else 231 #define wm8994_gpio_dbg_show NULL 232 #endif 233 234 static struct gpio_chip template_chip = { 235 .label = "wm8994", 236 .owner = THIS_MODULE, 237 .request = wm8994_gpio_request, 238 .direction_input = wm8994_gpio_direction_in, 239 .get = wm8994_gpio_get, 240 .direction_output = wm8994_gpio_direction_out, 241 .set = wm8994_gpio_set, 242 .to_irq = wm8994_gpio_to_irq, 243 .dbg_show = wm8994_gpio_dbg_show, 244 .can_sleep = 1, 245 }; 246 247 static int __devinit wm8994_gpio_probe(struct platform_device *pdev) 248 { 249 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); 250 struct wm8994_pdata *pdata = wm8994->dev->platform_data; 251 struct wm8994_gpio *wm8994_gpio; 252 int ret; 253 254 wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL); 255 if (wm8994_gpio == NULL) 256 return -ENOMEM; 257 258 wm8994_gpio->wm8994 = wm8994; 259 wm8994_gpio->gpio_chip = template_chip; 260 wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX; 261 wm8994_gpio->gpio_chip.dev = &pdev->dev; 262 if (pdata && pdata->gpio_base) 263 wm8994_gpio->gpio_chip.base = pdata->gpio_base; 264 else 265 wm8994_gpio->gpio_chip.base = -1; 266 267 ret = gpiochip_add(&wm8994_gpio->gpio_chip); 268 if (ret < 0) { 269 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", 270 ret); 271 goto err; 272 } 273 274 platform_set_drvdata(pdev, wm8994_gpio); 275 276 return ret; 277 278 err: 279 kfree(wm8994_gpio); 280 return ret; 281 } 282 283 static int __devexit wm8994_gpio_remove(struct platform_device *pdev) 284 { 285 struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev); 286 int ret; 287 288 ret = gpiochip_remove(&wm8994_gpio->gpio_chip); 289 if (ret == 0) 290 kfree(wm8994_gpio); 291 292 return ret; 293 } 294 295 static struct platform_driver wm8994_gpio_driver = { 296 .driver.name = "wm8994-gpio", 297 .driver.owner = THIS_MODULE, 298 .probe = wm8994_gpio_probe, 299 .remove = __devexit_p(wm8994_gpio_remove), 300 }; 301 302 static int __init wm8994_gpio_init(void) 303 { 304 return platform_driver_register(&wm8994_gpio_driver); 305 } 306 subsys_initcall(wm8994_gpio_init); 307 308 static void __exit wm8994_gpio_exit(void) 309 { 310 platform_driver_unregister(&wm8994_gpio_driver); 311 } 312 module_exit(wm8994_gpio_exit); 313 314 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 315 MODULE_DESCRIPTION("GPIO interface for WM8994"); 316 MODULE_LICENSE("GPL"); 317 MODULE_ALIAS("platform:wm8994-gpio"); 318