1 /* 2 * rtc-tps65910.c -- TPS65910 Real Time Clock interface 3 * 4 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. 5 * Author: Venu Byravarasu <vbyravarasu@nvidia.com> 6 * 7 * Based on original TI driver rtc-twl.c 8 * Copyright (C) 2007 MontaVista Software, Inc 9 * Author: Alexandre Rusev <source@mvista.com> 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * as published by the Free Software Foundation; either version 14 * 2 of the License, or (at your option) any later version. 15 */ 16 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/init.h> 20 #include <linux/module.h> 21 #include <linux/types.h> 22 #include <linux/rtc.h> 23 #include <linux/bcd.h> 24 #include <linux/platform_device.h> 25 #include <linux/interrupt.h> 26 #include <linux/mfd/tps65910.h> 27 28 struct tps65910_rtc { 29 struct rtc_device *rtc; 30 /* To store the list of enabled interrupts */ 31 u32 irqstat; 32 }; 33 34 /* Total number of RTC registers needed to set time*/ 35 #define NUM_TIME_REGS (TPS65910_YEARS - TPS65910_SECONDS + 1) 36 37 static int tps65910_rtc_alarm_irq_enable(struct device *dev, unsigned enabled) 38 { 39 struct tps65910 *tps = dev_get_drvdata(dev->parent); 40 u8 val = 0; 41 42 if (enabled) 43 val = TPS65910_RTC_INTERRUPTS_IT_ALARM; 44 45 return regmap_write(tps->regmap, TPS65910_RTC_INTERRUPTS, val); 46 } 47 48 /* 49 * Gets current tps65910 RTC time and date parameters. 50 * 51 * The RTC's time/alarm representation is not what gmtime(3) requires 52 * Linux to use: 53 * 54 * - Months are 1..12 vs Linux 0-11 55 * - Years are 0..99 vs Linux 1900..N (we assume 21st century) 56 */ 57 static int tps65910_rtc_read_time(struct device *dev, struct rtc_time *tm) 58 { 59 unsigned char rtc_data[NUM_TIME_REGS]; 60 struct tps65910 *tps = dev_get_drvdata(dev->parent); 61 int ret; 62 63 /* Copy RTC counting registers to static registers or latches */ 64 ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, 65 TPS65910_RTC_CTRL_GET_TIME, TPS65910_RTC_CTRL_GET_TIME); 66 if (ret < 0) { 67 dev_err(dev, "RTC CTRL reg update failed with err:%d\n", ret); 68 return ret; 69 } 70 71 ret = regmap_bulk_read(tps->regmap, TPS65910_SECONDS, rtc_data, 72 NUM_TIME_REGS); 73 if (ret < 0) { 74 dev_err(dev, "reading from RTC failed with err:%d\n", ret); 75 return ret; 76 } 77 78 tm->tm_sec = bcd2bin(rtc_data[0]); 79 tm->tm_min = bcd2bin(rtc_data[1]); 80 tm->tm_hour = bcd2bin(rtc_data[2]); 81 tm->tm_mday = bcd2bin(rtc_data[3]); 82 tm->tm_mon = bcd2bin(rtc_data[4]) - 1; 83 tm->tm_year = bcd2bin(rtc_data[5]) + 100; 84 85 return ret; 86 } 87 88 static int tps65910_rtc_set_time(struct device *dev, struct rtc_time *tm) 89 { 90 unsigned char rtc_data[NUM_TIME_REGS]; 91 struct tps65910 *tps = dev_get_drvdata(dev->parent); 92 int ret; 93 94 rtc_data[0] = bin2bcd(tm->tm_sec); 95 rtc_data[1] = bin2bcd(tm->tm_min); 96 rtc_data[2] = bin2bcd(tm->tm_hour); 97 rtc_data[3] = bin2bcd(tm->tm_mday); 98 rtc_data[4] = bin2bcd(tm->tm_mon + 1); 99 rtc_data[5] = bin2bcd(tm->tm_year - 100); 100 101 /* Stop RTC while updating the RTC time registers */ 102 ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, 103 TPS65910_RTC_CTRL_STOP_RTC, 0); 104 if (ret < 0) { 105 dev_err(dev, "RTC stop failed with err:%d\n", ret); 106 return ret; 107 } 108 109 /* update all the time registers in one shot */ 110 ret = regmap_bulk_write(tps->regmap, TPS65910_SECONDS, rtc_data, 111 NUM_TIME_REGS); 112 if (ret < 0) { 113 dev_err(dev, "rtc_set_time error %d\n", ret); 114 return ret; 115 } 116 117 /* Start back RTC */ 118 ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, 119 TPS65910_RTC_CTRL_STOP_RTC, 1); 120 if (ret < 0) 121 dev_err(dev, "RTC start failed with err:%d\n", ret); 122 123 return ret; 124 } 125 126 /* 127 * Gets current tps65910 RTC alarm time. 128 */ 129 static int tps65910_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 130 { 131 unsigned char alarm_data[NUM_TIME_REGS]; 132 u32 int_val; 133 struct tps65910 *tps = dev_get_drvdata(dev->parent); 134 int ret; 135 136 ret = regmap_bulk_read(tps->regmap, TPS65910_SECONDS, alarm_data, 137 NUM_TIME_REGS); 138 if (ret < 0) { 139 dev_err(dev, "rtc_read_alarm error %d\n", ret); 140 return ret; 141 } 142 143 alm->time.tm_sec = bcd2bin(alarm_data[0]); 144 alm->time.tm_min = bcd2bin(alarm_data[1]); 145 alm->time.tm_hour = bcd2bin(alarm_data[2]); 146 alm->time.tm_mday = bcd2bin(alarm_data[3]); 147 alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1; 148 alm->time.tm_year = bcd2bin(alarm_data[5]) + 100; 149 150 ret = regmap_read(tps->regmap, TPS65910_RTC_INTERRUPTS, &int_val); 151 if (ret < 0) 152 return ret; 153 154 if (int_val & TPS65910_RTC_INTERRUPTS_IT_ALARM) 155 alm->enabled = 1; 156 157 return ret; 158 } 159 160 static int tps65910_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 161 { 162 unsigned char alarm_data[NUM_TIME_REGS]; 163 struct tps65910 *tps = dev_get_drvdata(dev->parent); 164 int ret; 165 166 ret = tps65910_rtc_alarm_irq_enable(dev, 0); 167 if (ret) 168 return ret; 169 170 alarm_data[0] = bin2bcd(alm->time.tm_sec); 171 alarm_data[1] = bin2bcd(alm->time.tm_min); 172 alarm_data[2] = bin2bcd(alm->time.tm_hour); 173 alarm_data[3] = bin2bcd(alm->time.tm_mday); 174 alarm_data[4] = bin2bcd(alm->time.tm_mon + 1); 175 alarm_data[5] = bin2bcd(alm->time.tm_year - 100); 176 177 /* update all the alarm registers in one shot */ 178 ret = regmap_bulk_write(tps->regmap, TPS65910_ALARM_SECONDS, 179 alarm_data, NUM_TIME_REGS); 180 if (ret) { 181 dev_err(dev, "rtc_set_alarm error %d\n", ret); 182 return ret; 183 } 184 185 if (alm->enabled) 186 ret = tps65910_rtc_alarm_irq_enable(dev, 1); 187 188 return ret; 189 } 190 191 static irqreturn_t tps65910_rtc_interrupt(int irq, void *rtc) 192 { 193 struct device *dev = rtc; 194 unsigned long events = 0; 195 struct tps65910 *tps = dev_get_drvdata(dev->parent); 196 struct tps65910_rtc *tps_rtc = dev_get_drvdata(dev); 197 int ret; 198 u32 rtc_reg; 199 200 ret = regmap_read(tps->regmap, TPS65910_RTC_STATUS, &rtc_reg); 201 if (ret) 202 return IRQ_NONE; 203 204 if (rtc_reg & TPS65910_RTC_STATUS_ALARM) 205 events = RTC_IRQF | RTC_AF; 206 207 ret = regmap_write(tps->regmap, TPS65910_RTC_STATUS, rtc_reg); 208 if (ret) 209 return IRQ_NONE; 210 211 /* Notify RTC core on event */ 212 rtc_update_irq(tps_rtc->rtc, 1, events); 213 214 return IRQ_HANDLED; 215 } 216 217 static const struct rtc_class_ops tps65910_rtc_ops = { 218 .read_time = tps65910_rtc_read_time, 219 .set_time = tps65910_rtc_set_time, 220 .read_alarm = tps65910_rtc_read_alarm, 221 .set_alarm = tps65910_rtc_set_alarm, 222 .alarm_irq_enable = tps65910_rtc_alarm_irq_enable, 223 }; 224 225 static int __devinit tps65910_rtc_probe(struct platform_device *pdev) 226 { 227 struct tps65910 *tps65910 = NULL; 228 struct tps65910_rtc *tps_rtc = NULL; 229 int ret; 230 int irq; 231 u32 rtc_reg; 232 233 tps65910 = dev_get_drvdata(pdev->dev.parent); 234 235 tps_rtc = devm_kzalloc(&pdev->dev, sizeof(struct tps65910_rtc), 236 GFP_KERNEL); 237 if (!tps_rtc) 238 return -ENOMEM; 239 240 /* Clear pending interrupts */ 241 ret = regmap_read(tps65910->regmap, TPS65910_RTC_STATUS, &rtc_reg); 242 if (ret < 0) 243 return ret; 244 245 ret = regmap_write(tps65910->regmap, TPS65910_RTC_STATUS, rtc_reg); 246 if (ret < 0) 247 return ret; 248 249 dev_dbg(&pdev->dev, "Enabling rtc-tps65910.\n"); 250 rtc_reg = TPS65910_RTC_CTRL_STOP_RTC; 251 ret = regmap_write(tps65910->regmap, TPS65910_RTC_CTRL, rtc_reg); 252 if (ret < 0) 253 return ret; 254 255 irq = platform_get_irq(pdev, 0); 256 if (irq <= 0) { 257 dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n", 258 irq); 259 return ret; 260 } 261 262 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 263 tps65910_rtc_interrupt, IRQF_TRIGGER_LOW, 264 "rtc-tps65910", &pdev->dev); 265 if (ret < 0) { 266 dev_err(&pdev->dev, "IRQ is not free.\n"); 267 return ret; 268 } 269 device_init_wakeup(&pdev->dev, 1); 270 271 tps_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev, 272 &tps65910_rtc_ops, THIS_MODULE); 273 if (IS_ERR(tps_rtc->rtc)) { 274 ret = PTR_ERR(tps_rtc->rtc); 275 dev_err(&pdev->dev, "RTC device register: err %d\n", ret); 276 return ret; 277 } 278 279 platform_set_drvdata(pdev, tps_rtc); 280 281 return 0; 282 } 283 284 /* 285 * Disable tps65910 RTC interrupts. 286 * Sets status flag to free. 287 */ 288 static int __devexit tps65910_rtc_remove(struct platform_device *pdev) 289 { 290 /* leave rtc running, but disable irqs */ 291 struct rtc_device *rtc = platform_get_drvdata(pdev); 292 293 tps65910_rtc_alarm_irq_enable(&rtc->dev, 0); 294 295 rtc_device_unregister(rtc); 296 return 0; 297 } 298 299 #ifdef CONFIG_PM_SLEEP 300 301 static int tps65910_rtc_suspend(struct device *dev) 302 { 303 struct tps65910 *tps = dev_get_drvdata(dev->parent); 304 u8 alarm = TPS65910_RTC_INTERRUPTS_IT_ALARM; 305 int ret; 306 307 /* Store current list of enabled interrupts*/ 308 ret = regmap_read(tps->regmap, TPS65910_RTC_INTERRUPTS, 309 &tps->rtc->irqstat); 310 if (ret < 0) 311 return ret; 312 313 /* Enable RTC ALARM interrupt only */ 314 return regmap_write(tps->regmap, TPS65910_RTC_INTERRUPTS, alarm); 315 } 316 317 static int tps65910_rtc_resume(struct device *dev) 318 { 319 struct tps65910 *tps = dev_get_drvdata(dev->parent); 320 321 /* Restore list of enabled interrupts before suspend */ 322 return regmap_write(tps->regmap, TPS65910_RTC_INTERRUPTS, 323 tps->rtc->irqstat); 324 } 325 326 static const struct dev_pm_ops tps65910_rtc_pm_ops = { 327 .suspend = tps65910_rtc_suspend, 328 .resume = tps65910_rtc_resume, 329 }; 330 331 #define DEV_PM_OPS (&tps65910_rtc_pm_ops) 332 #else 333 #define DEV_PM_OPS NULL 334 #endif 335 336 static struct platform_driver tps65910_rtc_driver = { 337 .probe = tps65910_rtc_probe, 338 .remove = __devexit_p(tps65910_rtc_remove), 339 .driver = { 340 .owner = THIS_MODULE, 341 .name = "tps65910-rtc", 342 .pm = DEV_PM_OPS, 343 }, 344 }; 345 346 module_platform_driver(tps65910_rtc_driver); 347 MODULE_ALIAS("platform:rtc-tps65910"); 348 MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>"); 349 MODULE_LICENSE("GPL"); 350