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