1 /* 2 * Retu/Tahvo MFD driver 3 * 4 * Copyright (C) 2004, 2005 Nokia Corporation 5 * 6 * Based on code written by Juha Yrjölä, David Weinehall and Mikko Ylinen. 7 * Rewritten by Aaro Koskinen. 8 * 9 * This file is subject to the terms and conditions of the GNU General 10 * Public License. See the file "COPYING" in the main directory of this 11 * archive for more details. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 */ 18 19 #include <linux/err.h> 20 #include <linux/i2c.h> 21 #include <linux/irq.h> 22 #include <linux/init.h> 23 #include <linux/slab.h> 24 #include <linux/mutex.h> 25 #include <linux/module.h> 26 #include <linux/regmap.h> 27 #include <linux/mfd/core.h> 28 #include <linux/mfd/retu.h> 29 #include <linux/interrupt.h> 30 #include <linux/moduleparam.h> 31 32 /* Registers */ 33 #define RETU_REG_ASICR 0x00 /* ASIC ID and revision */ 34 #define RETU_REG_ASICR_VILMA (1 << 7) /* Bit indicating Vilma */ 35 #define RETU_REG_IDR 0x01 /* Interrupt ID */ 36 #define RETU_REG_IMR 0x02 /* Interrupt mask (Retu) */ 37 #define TAHVO_REG_IMR 0x03 /* Interrupt mask (Tahvo) */ 38 39 /* Interrupt sources */ 40 #define RETU_INT_PWR 0 /* Power button */ 41 42 struct retu_dev { 43 struct regmap *regmap; 44 struct device *dev; 45 struct mutex mutex; 46 struct regmap_irq_chip_data *irq_data; 47 }; 48 49 static struct resource retu_pwrbutton_res[] = { 50 { 51 .name = "retu-pwrbutton", 52 .start = RETU_INT_PWR, 53 .end = RETU_INT_PWR, 54 .flags = IORESOURCE_IRQ, 55 }, 56 }; 57 58 static struct mfd_cell retu_devs[] = { 59 { 60 .name = "retu-wdt" 61 }, 62 { 63 .name = "retu-pwrbutton", 64 .resources = retu_pwrbutton_res, 65 .num_resources = ARRAY_SIZE(retu_pwrbutton_res), 66 } 67 }; 68 69 static struct regmap_irq retu_irqs[] = { 70 [RETU_INT_PWR] = { 71 .mask = 1 << RETU_INT_PWR, 72 } 73 }; 74 75 static struct regmap_irq_chip retu_irq_chip = { 76 .name = "RETU", 77 .irqs = retu_irqs, 78 .num_irqs = ARRAY_SIZE(retu_irqs), 79 .num_regs = 1, 80 .status_base = RETU_REG_IDR, 81 .mask_base = RETU_REG_IMR, 82 .ack_base = RETU_REG_IDR, 83 }; 84 85 /* Retu device registered for the power off. */ 86 static struct retu_dev *retu_pm_power_off; 87 88 static struct resource tahvo_usb_res[] = { 89 { 90 .name = "tahvo-usb", 91 .start = TAHVO_INT_VBUS, 92 .end = TAHVO_INT_VBUS, 93 .flags = IORESOURCE_IRQ, 94 }, 95 }; 96 97 static struct mfd_cell tahvo_devs[] = { 98 { 99 .name = "tahvo-usb", 100 .resources = tahvo_usb_res, 101 .num_resources = ARRAY_SIZE(tahvo_usb_res), 102 }, 103 }; 104 105 static struct regmap_irq tahvo_irqs[] = { 106 [TAHVO_INT_VBUS] = { 107 .mask = 1 << TAHVO_INT_VBUS, 108 } 109 }; 110 111 static struct regmap_irq_chip tahvo_irq_chip = { 112 .name = "TAHVO", 113 .irqs = tahvo_irqs, 114 .num_irqs = ARRAY_SIZE(tahvo_irqs), 115 .num_regs = 1, 116 .status_base = RETU_REG_IDR, 117 .mask_base = TAHVO_REG_IMR, 118 .ack_base = RETU_REG_IDR, 119 }; 120 121 static const struct retu_data { 122 char *chip_name; 123 char *companion_name; 124 struct regmap_irq_chip *irq_chip; 125 struct mfd_cell *children; 126 int nchildren; 127 } retu_data[] = { 128 [0] = { 129 .chip_name = "Retu", 130 .companion_name = "Vilma", 131 .irq_chip = &retu_irq_chip, 132 .children = retu_devs, 133 .nchildren = ARRAY_SIZE(retu_devs), 134 }, 135 [1] = { 136 .chip_name = "Tahvo", 137 .companion_name = "Betty", 138 .irq_chip = &tahvo_irq_chip, 139 .children = tahvo_devs, 140 .nchildren = ARRAY_SIZE(tahvo_devs), 141 } 142 }; 143 144 int retu_read(struct retu_dev *rdev, u8 reg) 145 { 146 int ret; 147 int value; 148 149 mutex_lock(&rdev->mutex); 150 ret = regmap_read(rdev->regmap, reg, &value); 151 mutex_unlock(&rdev->mutex); 152 153 return ret ? ret : value; 154 } 155 EXPORT_SYMBOL_GPL(retu_read); 156 157 int retu_write(struct retu_dev *rdev, u8 reg, u16 data) 158 { 159 int ret; 160 161 mutex_lock(&rdev->mutex); 162 ret = regmap_write(rdev->regmap, reg, data); 163 mutex_unlock(&rdev->mutex); 164 165 return ret; 166 } 167 EXPORT_SYMBOL_GPL(retu_write); 168 169 static void retu_power_off(void) 170 { 171 struct retu_dev *rdev = retu_pm_power_off; 172 int reg; 173 174 mutex_lock(&retu_pm_power_off->mutex); 175 176 /* Ignore power button state */ 177 regmap_read(rdev->regmap, RETU_REG_CC1, ®); 178 regmap_write(rdev->regmap, RETU_REG_CC1, reg | 2); 179 180 /* Expire watchdog immediately */ 181 regmap_write(rdev->regmap, RETU_REG_WATCHDOG, 0); 182 183 /* Wait for poweroff */ 184 for (;;) 185 cpu_relax(); 186 187 mutex_unlock(&retu_pm_power_off->mutex); 188 } 189 190 static int retu_regmap_read(void *context, const void *reg, size_t reg_size, 191 void *val, size_t val_size) 192 { 193 int ret; 194 struct device *dev = context; 195 struct i2c_client *i2c = to_i2c_client(dev); 196 197 BUG_ON(reg_size != 1 || val_size != 2); 198 199 ret = i2c_smbus_read_word_data(i2c, *(u8 const *)reg); 200 if (ret < 0) 201 return ret; 202 203 *(u16 *)val = ret; 204 return 0; 205 } 206 207 static int retu_regmap_write(void *context, const void *data, size_t count) 208 { 209 u8 reg; 210 u16 val; 211 struct device *dev = context; 212 struct i2c_client *i2c = to_i2c_client(dev); 213 214 BUG_ON(count != sizeof(reg) + sizeof(val)); 215 memcpy(®, data, sizeof(reg)); 216 memcpy(&val, data + sizeof(reg), sizeof(val)); 217 return i2c_smbus_write_word_data(i2c, reg, val); 218 } 219 220 static struct regmap_bus retu_bus = { 221 .read = retu_regmap_read, 222 .write = retu_regmap_write, 223 .val_format_endian_default = REGMAP_ENDIAN_NATIVE, 224 }; 225 226 static struct regmap_config retu_config = { 227 .reg_bits = 8, 228 .val_bits = 16, 229 }; 230 231 static int retu_probe(struct i2c_client *i2c, const struct i2c_device_id *id) 232 { 233 struct retu_data const *rdat; 234 struct retu_dev *rdev; 235 int ret; 236 237 if (i2c->addr > ARRAY_SIZE(retu_data)) 238 return -ENODEV; 239 rdat = &retu_data[i2c->addr - 1]; 240 241 rdev = devm_kzalloc(&i2c->dev, sizeof(*rdev), GFP_KERNEL); 242 if (rdev == NULL) 243 return -ENOMEM; 244 245 i2c_set_clientdata(i2c, rdev); 246 rdev->dev = &i2c->dev; 247 mutex_init(&rdev->mutex); 248 rdev->regmap = devm_regmap_init(&i2c->dev, &retu_bus, &i2c->dev, 249 &retu_config); 250 if (IS_ERR(rdev->regmap)) 251 return PTR_ERR(rdev->regmap); 252 253 ret = retu_read(rdev, RETU_REG_ASICR); 254 if (ret < 0) { 255 dev_err(rdev->dev, "could not read %s revision: %d\n", 256 rdat->chip_name, ret); 257 return ret; 258 } 259 260 dev_info(rdev->dev, "%s%s%s v%d.%d found\n", rdat->chip_name, 261 (ret & RETU_REG_ASICR_VILMA) ? " & " : "", 262 (ret & RETU_REG_ASICR_VILMA) ? rdat->companion_name : "", 263 (ret >> 4) & 0x7, ret & 0xf); 264 265 /* Mask all interrupts. */ 266 ret = retu_write(rdev, rdat->irq_chip->mask_base, 0xffff); 267 if (ret < 0) 268 return ret; 269 270 ret = regmap_add_irq_chip(rdev->regmap, i2c->irq, IRQF_ONESHOT, -1, 271 rdat->irq_chip, &rdev->irq_data); 272 if (ret < 0) 273 return ret; 274 275 ret = mfd_add_devices(rdev->dev, -1, rdat->children, rdat->nchildren, 276 NULL, regmap_irq_chip_get_base(rdev->irq_data), 277 NULL); 278 if (ret < 0) { 279 regmap_del_irq_chip(i2c->irq, rdev->irq_data); 280 return ret; 281 } 282 283 if (i2c->addr == 1 && !pm_power_off) { 284 retu_pm_power_off = rdev; 285 pm_power_off = retu_power_off; 286 } 287 288 return 0; 289 } 290 291 static int retu_remove(struct i2c_client *i2c) 292 { 293 struct retu_dev *rdev = i2c_get_clientdata(i2c); 294 295 if (retu_pm_power_off == rdev) { 296 pm_power_off = NULL; 297 retu_pm_power_off = NULL; 298 } 299 mfd_remove_devices(rdev->dev); 300 regmap_del_irq_chip(i2c->irq, rdev->irq_data); 301 302 return 0; 303 } 304 305 static const struct i2c_device_id retu_id[] = { 306 { "retu-mfd", 0 }, 307 { "tahvo-mfd", 0 }, 308 { } 309 }; 310 MODULE_DEVICE_TABLE(i2c, retu_id); 311 312 static struct i2c_driver retu_driver = { 313 .driver = { 314 .name = "retu-mfd", 315 .owner = THIS_MODULE, 316 }, 317 .probe = retu_probe, 318 .remove = retu_remove, 319 .id_table = retu_id, 320 }; 321 module_i2c_driver(retu_driver); 322 323 MODULE_DESCRIPTION("Retu MFD driver"); 324 MODULE_AUTHOR("Juha Yrjölä"); 325 MODULE_AUTHOR("David Weinehall"); 326 MODULE_AUTHOR("Mikko Ylinen"); 327 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); 328 MODULE_LICENSE("GPL"); 329