Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 1 | /* |
| 2 | * Intersil ISL1208 rtc class driver |
| 3 | * |
| 4 | * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License as published by the |
| 8 | * Free Software Foundation; either version 2 of the License, or (at your |
| 9 | * option) any later version. |
| 10 | * |
| 11 | */ |
| 12 | |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/i2c.h> |
| 15 | #include <linux/bcd.h> |
| 16 | #include <linux/rtc.h> |
| 17 | |
| 18 | #define DRV_VERSION "0.3" |
| 19 | |
| 20 | /* Register map */ |
| 21 | /* rtc section */ |
| 22 | #define ISL1208_REG_SC 0x00 |
| 23 | #define ISL1208_REG_MN 0x01 |
| 24 | #define ISL1208_REG_HR 0x02 |
| 25 | #define ISL1208_REG_HR_MIL (1<<7) /* 24h/12h mode */ |
| 26 | #define ISL1208_REG_HR_PM (1<<5) /* PM/AM bit in 12h mode */ |
| 27 | #define ISL1208_REG_DT 0x03 |
| 28 | #define ISL1208_REG_MO 0x04 |
| 29 | #define ISL1208_REG_YR 0x05 |
| 30 | #define ISL1208_REG_DW 0x06 |
| 31 | #define ISL1208_RTC_SECTION_LEN 7 |
| 32 | |
| 33 | /* control/status section */ |
| 34 | #define ISL1208_REG_SR 0x07 |
| 35 | #define ISL1208_REG_SR_ARST (1<<7) /* auto reset */ |
| 36 | #define ISL1208_REG_SR_XTOSCB (1<<6) /* crystal oscillator */ |
| 37 | #define ISL1208_REG_SR_WRTC (1<<4) /* write rtc */ |
| 38 | #define ISL1208_REG_SR_ALM (1<<2) /* alarm */ |
| 39 | #define ISL1208_REG_SR_BAT (1<<1) /* battery */ |
| 40 | #define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */ |
| 41 | #define ISL1208_REG_INT 0x08 |
| 42 | #define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */ |
| 43 | #define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */ |
| 44 | #define ISL1208_REG_09 0x09 /* reserved */ |
| 45 | #define ISL1208_REG_ATR 0x0a |
| 46 | #define ISL1208_REG_DTR 0x0b |
| 47 | |
| 48 | /* alarm section */ |
| 49 | #define ISL1208_REG_SCA 0x0c |
| 50 | #define ISL1208_REG_MNA 0x0d |
| 51 | #define ISL1208_REG_HRA 0x0e |
| 52 | #define ISL1208_REG_DTA 0x0f |
| 53 | #define ISL1208_REG_MOA 0x10 |
| 54 | #define ISL1208_REG_DWA 0x11 |
| 55 | #define ISL1208_ALARM_SECTION_LEN 6 |
| 56 | |
| 57 | /* user section */ |
| 58 | #define ISL1208_REG_USR1 0x12 |
| 59 | #define ISL1208_REG_USR2 0x13 |
| 60 | #define ISL1208_USR_SECTION_LEN 2 |
| 61 | |
| 62 | static struct i2c_driver isl1208_driver; |
| 63 | |
| 64 | /* block read */ |
| 65 | static int |
| 66 | isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[], |
| 67 | unsigned len) |
| 68 | { |
| 69 | u8 reg_addr[1] = { reg }; |
| 70 | struct i2c_msg msgs[2] = { |
| 71 | { |
| 72 | .addr = client->addr, |
| 73 | .len = sizeof(reg_addr), |
| 74 | .buf = reg_addr |
| 75 | }, |
| 76 | { |
| 77 | .addr = client->addr, |
| 78 | .flags = I2C_M_RD, |
| 79 | .len = len, |
| 80 | .buf = buf |
| 81 | } |
| 82 | }; |
| 83 | int ret; |
| 84 | |
| 85 | BUG_ON(reg > ISL1208_REG_USR2); |
| 86 | BUG_ON(reg + len > ISL1208_REG_USR2 + 1); |
| 87 | |
| 88 | ret = i2c_transfer(client->adapter, msgs, 2); |
| 89 | if (ret > 0) |
| 90 | ret = 0; |
| 91 | return ret; |
| 92 | } |
| 93 | |
| 94 | /* block write */ |
| 95 | static int |
| 96 | isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[], |
| 97 | unsigned len) |
| 98 | { |
| 99 | u8 i2c_buf[ISL1208_REG_USR2 + 2]; |
| 100 | struct i2c_msg msgs[1] = { |
| 101 | { |
| 102 | .addr = client->addr, |
| 103 | .len = len + 1, |
| 104 | .buf = i2c_buf |
| 105 | } |
| 106 | }; |
| 107 | int ret; |
| 108 | |
| 109 | BUG_ON(reg > ISL1208_REG_USR2); |
| 110 | BUG_ON(reg + len > ISL1208_REG_USR2 + 1); |
| 111 | |
| 112 | i2c_buf[0] = reg; |
| 113 | memcpy(&i2c_buf[1], &buf[0], len); |
| 114 | |
| 115 | ret = i2c_transfer(client->adapter, msgs, 1); |
| 116 | if (ret > 0) |
| 117 | ret = 0; |
| 118 | return ret; |
| 119 | } |
| 120 | |
| 121 | /* simple check to see whether we have a isl1208 */ |
| 122 | static int |
| 123 | isl1208_i2c_validate_client(struct i2c_client *client) |
| 124 | { |
| 125 | u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; |
| 126 | u8 zero_mask[ISL1208_RTC_SECTION_LEN] = { |
| 127 | 0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8 |
| 128 | }; |
| 129 | int i; |
| 130 | int ret; |
| 131 | |
| 132 | ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); |
| 133 | if (ret < 0) |
| 134 | return ret; |
| 135 | |
| 136 | for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) { |
| 137 | if (regs[i] & zero_mask[i]) /* check if bits are cleared */ |
| 138 | return -ENODEV; |
| 139 | } |
| 140 | |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | static int |
| 145 | isl1208_i2c_get_sr(struct i2c_client *client) |
| 146 | { |
| 147 | return i2c_smbus_read_byte_data(client, ISL1208_REG_SR); |
| 148 | } |
| 149 | |
| 150 | static int |
| 151 | isl1208_i2c_get_atr(struct i2c_client *client) |
| 152 | { |
| 153 | int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR); |
| 154 | if (atr < 0) |
| 155 | return atr; |
| 156 | |
| 157 | /* The 6bit value in the ATR register controls the load |
| 158 | * capacitance C_load * in steps of 0.25pF |
| 159 | * |
| 160 | * bit (1<<5) of the ATR register is inverted |
| 161 | * |
| 162 | * C_load(ATR=0x20) = 4.50pF |
| 163 | * C_load(ATR=0x00) = 12.50pF |
| 164 | * C_load(ATR=0x1f) = 20.25pF |
| 165 | * |
| 166 | */ |
| 167 | |
| 168 | atr &= 0x3f; /* mask out lsb */ |
| 169 | atr ^= 1 << 5; /* invert 6th bit */ |
| 170 | atr += 2 * 9; /* add offset of 4.5pF; unit[atr] = 0.25pF */ |
| 171 | |
| 172 | return atr; |
| 173 | } |
| 174 | |
| 175 | static int |
| 176 | isl1208_i2c_get_dtr(struct i2c_client *client) |
| 177 | { |
| 178 | int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR); |
| 179 | if (dtr < 0) |
| 180 | return -EIO; |
| 181 | |
| 182 | /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */ |
| 183 | dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1); |
| 184 | |
| 185 | return dtr; |
| 186 | } |
| 187 | |
| 188 | static int |
| 189 | isl1208_i2c_get_usr(struct i2c_client *client) |
| 190 | { |
| 191 | u8 buf[ISL1208_USR_SECTION_LEN] = { 0, }; |
| 192 | int ret; |
| 193 | |
| 194 | ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf, |
| 195 | ISL1208_USR_SECTION_LEN); |
| 196 | if (ret < 0) |
| 197 | return ret; |
| 198 | |
| 199 | return (buf[1] << 8) | buf[0]; |
| 200 | } |
| 201 | |
| 202 | static int |
| 203 | isl1208_i2c_set_usr(struct i2c_client *client, u16 usr) |
| 204 | { |
| 205 | u8 buf[ISL1208_USR_SECTION_LEN]; |
| 206 | |
| 207 | buf[0] = usr & 0xff; |
| 208 | buf[1] = (usr >> 8) & 0xff; |
| 209 | |
| 210 | return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf, |
| 211 | ISL1208_USR_SECTION_LEN); |
| 212 | } |
| 213 | |
| 214 | static int |
| 215 | isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable) |
| 216 | { |
| 217 | int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); |
| 218 | |
| 219 | if (icr < 0) { |
| 220 | dev_err(&client->dev, "%s: reading INT failed\n", __func__); |
| 221 | return icr; |
| 222 | } |
| 223 | |
| 224 | if (enable) |
| 225 | icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM; |
| 226 | else |
| 227 | icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM); |
| 228 | |
| 229 | icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr); |
| 230 | if (icr < 0) { |
| 231 | dev_err(&client->dev, "%s: writing INT failed\n", __func__); |
| 232 | return icr; |
| 233 | } |
| 234 | |
| 235 | return 0; |
| 236 | } |
| 237 | |
| 238 | static int |
| 239 | isl1208_rtc_proc(struct device *dev, struct seq_file *seq) |
| 240 | { |
| 241 | struct i2c_client *const client = to_i2c_client(dev); |
| 242 | int sr, dtr, atr, usr; |
| 243 | |
| 244 | sr = isl1208_i2c_get_sr(client); |
| 245 | if (sr < 0) { |
| 246 | dev_err(&client->dev, "%s: reading SR failed\n", __func__); |
| 247 | return sr; |
| 248 | } |
| 249 | |
| 250 | seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n", |
| 251 | (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "", |
| 252 | (sr & ISL1208_REG_SR_BAT) ? " BAT" : "", |
| 253 | (sr & ISL1208_REG_SR_ALM) ? " ALM" : "", |
| 254 | (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "", |
| 255 | (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "", |
| 256 | (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr); |
| 257 | |
| 258 | seq_printf(seq, "batt_status\t: %s\n", |
| 259 | (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay"); |
| 260 | |
| 261 | dtr = isl1208_i2c_get_dtr(client); |
| 262 | if (dtr >= 0 - 1) |
| 263 | seq_printf(seq, "digital_trim\t: %d ppm\n", dtr); |
| 264 | |
| 265 | atr = isl1208_i2c_get_atr(client); |
| 266 | if (atr >= 0) |
| 267 | seq_printf(seq, "analog_trim\t: %d.%.2d pF\n", |
| 268 | atr >> 2, (atr & 0x3) * 25); |
| 269 | |
| 270 | usr = isl1208_i2c_get_usr(client); |
| 271 | if (usr >= 0) |
| 272 | seq_printf(seq, "user_data\t: 0x%.4x\n", usr); |
| 273 | |
| 274 | return 0; |
| 275 | } |
| 276 | |
| 277 | static int |
| 278 | isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm) |
| 279 | { |
| 280 | int sr; |
| 281 | u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; |
| 282 | |
| 283 | sr = isl1208_i2c_get_sr(client); |
| 284 | if (sr < 0) { |
| 285 | dev_err(&client->dev, "%s: reading SR failed\n", __func__); |
| 286 | return -EIO; |
| 287 | } |
| 288 | |
| 289 | sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); |
| 290 | if (sr < 0) { |
| 291 | dev_err(&client->dev, "%s: reading RTC section failed\n", |
| 292 | __func__); |
| 293 | return sr; |
| 294 | } |
| 295 | |
| 296 | tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]); |
| 297 | tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]); |
| 298 | |
| 299 | /* HR field has a more complex interpretation */ |
| 300 | { |
| 301 | const u8 _hr = regs[ISL1208_REG_HR]; |
| 302 | if (_hr & ISL1208_REG_HR_MIL) /* 24h format */ |
| 303 | tm->tm_hour = bcd2bin(_hr & 0x3f); |
| 304 | else { |
| 305 | /* 12h format */ |
| 306 | tm->tm_hour = bcd2bin(_hr & 0x1f); |
| 307 | if (_hr & ISL1208_REG_HR_PM) /* PM flag set */ |
| 308 | tm->tm_hour += 12; |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]); |
| 313 | tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */ |
| 314 | tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100; |
| 315 | tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]); |
| 316 | |
| 317 | return 0; |
| 318 | } |
| 319 | |
| 320 | static int |
| 321 | isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) |
| 322 | { |
| 323 | struct rtc_time *const tm = &alarm->time; |
| 324 | u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; |
| 325 | int icr, yr, sr = isl1208_i2c_get_sr(client); |
| 326 | |
| 327 | if (sr < 0) { |
| 328 | dev_err(&client->dev, "%s: reading SR failed\n", __func__); |
| 329 | return sr; |
| 330 | } |
| 331 | |
| 332 | sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs, |
| 333 | ISL1208_ALARM_SECTION_LEN); |
| 334 | if (sr < 0) { |
| 335 | dev_err(&client->dev, "%s: reading alarm section failed\n", |
| 336 | __func__); |
| 337 | return sr; |
| 338 | } |
| 339 | |
| 340 | /* MSB of each alarm register is an enable bit */ |
| 341 | tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f); |
| 342 | tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f); |
| 343 | tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f); |
| 344 | tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f); |
| 345 | tm->tm_mon = |
| 346 | bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1; |
| 347 | tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03); |
| 348 | |
| 349 | /* The alarm doesn't store the year so get it from the rtc section */ |
| 350 | yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR); |
| 351 | if (yr < 0) { |
| 352 | dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__); |
| 353 | return yr; |
| 354 | } |
| 355 | tm->tm_year = bcd2bin(yr) + 100; |
| 356 | |
| 357 | icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); |
| 358 | if (icr < 0) { |
| 359 | dev_err(&client->dev, "%s: reading INT failed\n", __func__); |
| 360 | return icr; |
| 361 | } |
| 362 | alarm->enabled = !!(icr & ISL1208_REG_INT_ALME); |
| 363 | |
| 364 | return 0; |
| 365 | } |
| 366 | |
| 367 | static int |
| 368 | isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) |
| 369 | { |
| 370 | struct rtc_time *alarm_tm = &alarm->time; |
| 371 | u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; |
| 372 | const int offs = ISL1208_REG_SCA; |
| 373 | struct rtc_time rtc_tm; |
| 374 | int err, enable; |
| 375 | |
| 376 | err = isl1208_i2c_read_time(client, &rtc_tm); |
| 377 | if (err) |
| 378 | return err; |
| 379 | |
| 380 | /* If the alarm time is before the current time disable the alarm */ |
| 381 | if (!alarm->enabled || rtc_tm_sub(alarm_tm, &rtc_tm) <= 0) |
| 382 | enable = 0x00; |
| 383 | else |
| 384 | enable = 0x80; |
| 385 | |
| 386 | /* Program the alarm and enable it for each setting */ |
| 387 | regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable; |
| 388 | regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable; |
| 389 | regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) | |
| 390 | ISL1208_REG_HR_MIL | enable; |
| 391 | |
| 392 | regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable; |
| 393 | regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable; |
| 394 | regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable; |
| 395 | |
| 396 | /* write ALARM registers */ |
| 397 | err = isl1208_i2c_set_regs(client, offs, regs, |
| 398 | ISL1208_ALARM_SECTION_LEN); |
| 399 | if (err < 0) { |
| 400 | dev_err(&client->dev, "%s: writing ALARM section failed\n", |
| 401 | __func__); |
| 402 | return err; |
| 403 | } |
| 404 | |
| 405 | err = isl1208_rtc_toggle_alarm(client, enable); |
| 406 | if (err) |
| 407 | return err; |
| 408 | |
| 409 | return 0; |
| 410 | } |
| 411 | |
| 412 | static int |
| 413 | isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| 414 | { |
| 415 | return isl1208_i2c_read_time(to_i2c_client(dev), tm); |
| 416 | } |
| 417 | |
| 418 | static int |
| 419 | isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm) |
| 420 | { |
| 421 | int sr; |
| 422 | u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; |
| 423 | |
| 424 | /* The clock has an 8 bit wide bcd-coded register (they never learn) |
| 425 | * for the year. tm_year is an offset from 1900 and we are interested |
| 426 | * in the 2000-2099 range, so any value less than 100 is invalid. |
| 427 | */ |
| 428 | if (tm->tm_year < 100) |
| 429 | return -EINVAL; |
| 430 | |
| 431 | regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec); |
| 432 | regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min); |
| 433 | regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL; |
| 434 | |
| 435 | regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday); |
| 436 | regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1); |
| 437 | regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100); |
| 438 | |
| 439 | regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7); |
| 440 | |
| 441 | sr = isl1208_i2c_get_sr(client); |
| 442 | if (sr < 0) { |
| 443 | dev_err(&client->dev, "%s: reading SR failed\n", __func__); |
| 444 | return sr; |
| 445 | } |
| 446 | |
| 447 | /* set WRTC */ |
| 448 | sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, |
| 449 | sr | ISL1208_REG_SR_WRTC); |
| 450 | if (sr < 0) { |
| 451 | dev_err(&client->dev, "%s: writing SR failed\n", __func__); |
| 452 | return sr; |
| 453 | } |
| 454 | |
| 455 | /* write RTC registers */ |
| 456 | sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); |
| 457 | if (sr < 0) { |
| 458 | dev_err(&client->dev, "%s: writing RTC section failed\n", |
| 459 | __func__); |
| 460 | return sr; |
| 461 | } |
| 462 | |
| 463 | /* clear WRTC again */ |
| 464 | sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, |
| 465 | sr & ~ISL1208_REG_SR_WRTC); |
| 466 | if (sr < 0) { |
| 467 | dev_err(&client->dev, "%s: writing SR failed\n", __func__); |
| 468 | return sr; |
| 469 | } |
| 470 | |
| 471 | return 0; |
| 472 | } |
| 473 | |
| 474 | |
| 475 | static int |
| 476 | isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| 477 | { |
| 478 | return isl1208_i2c_set_time(to_i2c_client(dev), tm); |
| 479 | } |
| 480 | |
| 481 | static int |
| 482 | isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| 483 | { |
| 484 | return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm); |
| 485 | } |
| 486 | |
| 487 | static int |
| 488 | isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| 489 | { |
| 490 | return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm); |
| 491 | } |
| 492 | |
| 493 | static irqreturn_t |
| 494 | isl1208_rtc_interrupt(int irq, void *data) |
| 495 | { |
| 496 | unsigned long timeout = jiffies + msecs_to_jiffies(1000); |
| 497 | struct i2c_client *client = data; |
| 498 | struct rtc_device *rtc = i2c_get_clientdata(client); |
| 499 | int handled = 0, sr, err; |
| 500 | |
| 501 | /* |
| 502 | * I2C reads get NAK'ed if we read straight away after an interrupt? |
| 503 | * Using a mdelay/msleep didn't seem to help either, so we work around |
| 504 | * this by continually trying to read the register for a short time. |
| 505 | */ |
| 506 | while (1) { |
| 507 | sr = isl1208_i2c_get_sr(client); |
| 508 | if (sr >= 0) |
| 509 | break; |
| 510 | |
| 511 | if (time_after(jiffies, timeout)) { |
| 512 | dev_err(&client->dev, "%s: reading SR failed\n", |
| 513 | __func__); |
| 514 | return sr; |
| 515 | } |
| 516 | } |
| 517 | |
| 518 | if (sr & ISL1208_REG_SR_ALM) { |
| 519 | dev_dbg(&client->dev, "alarm!\n"); |
| 520 | |
| 521 | rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF); |
| 522 | |
| 523 | /* Clear the alarm */ |
| 524 | sr &= ~ISL1208_REG_SR_ALM; |
| 525 | sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); |
| 526 | if (sr < 0) |
| 527 | dev_err(&client->dev, "%s: writing SR failed\n", |
| 528 | __func__); |
| 529 | else |
| 530 | handled = 1; |
| 531 | |
| 532 | /* Disable the alarm */ |
| 533 | err = isl1208_rtc_toggle_alarm(client, 0); |
| 534 | if (err) |
| 535 | return err; |
| 536 | } |
| 537 | |
| 538 | return handled ? IRQ_HANDLED : IRQ_NONE; |
| 539 | } |
| 540 | |
| 541 | static const struct rtc_class_ops isl1208_rtc_ops = { |
| 542 | .proc = isl1208_rtc_proc, |
| 543 | .read_time = isl1208_rtc_read_time, |
| 544 | .set_time = isl1208_rtc_set_time, |
| 545 | .read_alarm = isl1208_rtc_read_alarm, |
| 546 | .set_alarm = isl1208_rtc_set_alarm, |
| 547 | }; |
| 548 | |
| 549 | /* sysfs interface */ |
| 550 | |
| 551 | static ssize_t |
| 552 | isl1208_sysfs_show_atrim(struct device *dev, |
| 553 | struct device_attribute *attr, char *buf) |
| 554 | { |
| 555 | int atr = isl1208_i2c_get_atr(to_i2c_client(dev)); |
| 556 | if (atr < 0) |
| 557 | return atr; |
| 558 | |
| 559 | return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25); |
| 560 | } |
| 561 | |
| 562 | static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL); |
| 563 | |
| 564 | static ssize_t |
| 565 | isl1208_sysfs_show_dtrim(struct device *dev, |
| 566 | struct device_attribute *attr, char *buf) |
| 567 | { |
| 568 | int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev)); |
| 569 | if (dtr < 0) |
| 570 | return dtr; |
| 571 | |
| 572 | return sprintf(buf, "%d ppm\n", dtr); |
| 573 | } |
| 574 | |
| 575 | static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL); |
| 576 | |
| 577 | static ssize_t |
| 578 | isl1208_sysfs_show_usr(struct device *dev, |
| 579 | struct device_attribute *attr, char *buf) |
| 580 | { |
| 581 | int usr = isl1208_i2c_get_usr(to_i2c_client(dev)); |
| 582 | if (usr < 0) |
| 583 | return usr; |
| 584 | |
| 585 | return sprintf(buf, "0x%.4x\n", usr); |
| 586 | } |
| 587 | |
| 588 | static ssize_t |
| 589 | isl1208_sysfs_store_usr(struct device *dev, |
| 590 | struct device_attribute *attr, |
| 591 | const char *buf, size_t count) |
| 592 | { |
| 593 | int usr = -1; |
| 594 | |
| 595 | if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) { |
| 596 | if (sscanf(buf, "%x", &usr) != 1) |
| 597 | return -EINVAL; |
| 598 | } else { |
| 599 | if (sscanf(buf, "%d", &usr) != 1) |
| 600 | return -EINVAL; |
| 601 | } |
| 602 | |
| 603 | if (usr < 0 || usr > 0xffff) |
| 604 | return -EINVAL; |
| 605 | |
| 606 | return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : count; |
| 607 | } |
| 608 | |
| 609 | static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr, |
| 610 | isl1208_sysfs_store_usr); |
| 611 | |
| 612 | static struct attribute *isl1208_rtc_attrs[] = { |
| 613 | &dev_attr_atrim.attr, |
| 614 | &dev_attr_dtrim.attr, |
| 615 | &dev_attr_usr.attr, |
| 616 | NULL |
| 617 | }; |
| 618 | |
| 619 | static const struct attribute_group isl1208_rtc_sysfs_files = { |
| 620 | .attrs = isl1208_rtc_attrs, |
| 621 | }; |
| 622 | |
| 623 | static int |
| 624 | isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) |
| 625 | { |
| 626 | int rc = 0; |
| 627 | struct rtc_device *rtc; |
| 628 | |
| 629 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) |
| 630 | return -ENODEV; |
| 631 | |
| 632 | if (isl1208_i2c_validate_client(client) < 0) |
| 633 | return -ENODEV; |
| 634 | |
| 635 | dev_info(&client->dev, |
| 636 | "chip found, driver version " DRV_VERSION "\n"); |
| 637 | |
| 638 | if (client->irq > 0) { |
| 639 | rc = devm_request_threaded_irq(&client->dev, client->irq, NULL, |
| 640 | isl1208_rtc_interrupt, |
| 641 | IRQF_SHARED | IRQF_ONESHOT, |
| 642 | isl1208_driver.driver.name, |
| 643 | client); |
| 644 | if (!rc) { |
| 645 | device_init_wakeup(&client->dev, 1); |
| 646 | enable_irq_wake(client->irq); |
| 647 | } else { |
| 648 | dev_err(&client->dev, |
| 649 | "Unable to request irq %d, no alarm support\n", |
| 650 | client->irq); |
| 651 | client->irq = 0; |
| 652 | } |
| 653 | } |
| 654 | |
| 655 | rtc = devm_rtc_device_register(&client->dev, isl1208_driver.driver.name, |
| 656 | &isl1208_rtc_ops, |
| 657 | THIS_MODULE); |
| 658 | if (IS_ERR(rtc)) |
| 659 | return PTR_ERR(rtc); |
| 660 | |
| 661 | i2c_set_clientdata(client, rtc); |
| 662 | |
| 663 | rc = isl1208_i2c_get_sr(client); |
| 664 | if (rc < 0) { |
| 665 | dev_err(&client->dev, "reading status failed\n"); |
| 666 | return rc; |
| 667 | } |
| 668 | |
| 669 | if (rc & ISL1208_REG_SR_RTCF) |
| 670 | dev_warn(&client->dev, "rtc power failure detected, " |
| 671 | "please set clock.\n"); |
| 672 | |
| 673 | rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files); |
| 674 | if (rc) |
| 675 | return rc; |
| 676 | |
| 677 | return 0; |
| 678 | } |
| 679 | |
| 680 | static int |
| 681 | isl1208_remove(struct i2c_client *client) |
| 682 | { |
| 683 | sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files); |
| 684 | |
| 685 | return 0; |
| 686 | } |
| 687 | |
| 688 | static const struct i2c_device_id isl1208_id[] = { |
| 689 | { "isl1208", 0 }, |
| 690 | { "isl1218", 0 }, |
| 691 | { } |
| 692 | }; |
| 693 | MODULE_DEVICE_TABLE(i2c, isl1208_id); |
| 694 | |
| 695 | static struct i2c_driver isl1208_driver = { |
| 696 | .driver = { |
| 697 | .name = "rtc-isl1208", |
| 698 | }, |
| 699 | .probe = isl1208_probe, |
| 700 | .remove = isl1208_remove, |
| 701 | .id_table = isl1208_id, |
| 702 | }; |
| 703 | |
| 704 | module_i2c_driver(isl1208_driver); |
| 705 | |
| 706 | MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>"); |
| 707 | MODULE_DESCRIPTION("Intersil ISL1208 RTC driver"); |
| 708 | MODULE_LICENSE("GPL"); |
| 709 | MODULE_VERSION(DRV_VERSION); |