rtc-mv.c revision 16380c153a69c3784d2afaddfe0a22f353046cf6
1/* 2 * Driver for the RTC in Marvell SoCs. 3 * 4 * This file is licensed under the terms of the GNU General Public 5 * License version 2. This program is licensed "as is" without any 6 * warranty of any kind, whether express or implied. 7 */ 8 9#include <linux/init.h> 10#include <linux/kernel.h> 11#include <linux/rtc.h> 12#include <linux/bcd.h> 13#include <linux/io.h> 14#include <linux/platform_device.h> 15#include <linux/delay.h> 16#include <linux/gfp.h> 17 18 19#define RTC_TIME_REG_OFFS 0 20#define RTC_SECONDS_OFFS 0 21#define RTC_MINUTES_OFFS 8 22#define RTC_HOURS_OFFS 16 23#define RTC_WDAY_OFFS 24 24#define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ 25 26#define RTC_DATE_REG_OFFS 4 27#define RTC_MDAY_OFFS 0 28#define RTC_MONTH_OFFS 8 29#define RTC_YEAR_OFFS 16 30 31#define RTC_ALARM_TIME_REG_OFFS 8 32#define RTC_ALARM_DATE_REG_OFFS 0xc 33#define RTC_ALARM_VALID (1 << 7) 34 35#define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 36#define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 37 38struct rtc_plat_data { 39 struct rtc_device *rtc; 40 void __iomem *ioaddr; 41 int irq; 42}; 43 44static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) 45{ 46 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 47 void __iomem *ioaddr = pdata->ioaddr; 48 u32 rtc_reg; 49 50 rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | 51 (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | 52 (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | 53 (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); 54 writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); 55 56 rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | 57 (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | 58 (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); 59 writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); 60 61 return 0; 62} 63 64static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) 65{ 66 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 67 void __iomem *ioaddr = pdata->ioaddr; 68 u32 rtc_time, rtc_date; 69 unsigned int year, month, day, hour, minute, second, wday; 70 71 rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); 72 rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); 73 74 second = rtc_time & 0x7f; 75 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 76 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 77 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 78 79 day = rtc_date & 0x3f; 80 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 81 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 82 83 tm->tm_sec = bcd2bin(second); 84 tm->tm_min = bcd2bin(minute); 85 tm->tm_hour = bcd2bin(hour); 86 tm->tm_mday = bcd2bin(day); 87 tm->tm_wday = bcd2bin(wday); 88 tm->tm_mon = bcd2bin(month) - 1; 89 /* hw counts from year 2000, but tm_year is relative to 1900 */ 90 tm->tm_year = bcd2bin(year) + 100; 91 92 return rtc_valid_tm(tm); 93} 94 95static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 96{ 97 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 98 void __iomem *ioaddr = pdata->ioaddr; 99 u32 rtc_time, rtc_date; 100 unsigned int year, month, day, hour, minute, second, wday; 101 102 rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS); 103 rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS); 104 105 second = rtc_time & 0x7f; 106 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 107 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 108 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 109 110 day = rtc_date & 0x3f; 111 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 112 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 113 114 alm->time.tm_sec = bcd2bin(second); 115 alm->time.tm_min = bcd2bin(minute); 116 alm->time.tm_hour = bcd2bin(hour); 117 alm->time.tm_mday = bcd2bin(day); 118 alm->time.tm_wday = bcd2bin(wday); 119 alm->time.tm_mon = bcd2bin(month) - 1; 120 /* hw counts from year 2000, but tm_year is relative to 1900 */ 121 alm->time.tm_year = bcd2bin(year) + 100; 122 123 if (rtc_valid_tm(&alm->time) < 0) { 124 dev_err(dev, "retrieved alarm date/time is not valid.\n"); 125 rtc_time_to_tm(0, &alm->time); 126 } 127 128 alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 129 return 0; 130} 131 132static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 133{ 134 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 135 void __iomem *ioaddr = pdata->ioaddr; 136 u32 rtc_reg = 0; 137 138 if (alm->time.tm_sec >= 0) 139 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) 140 << RTC_SECONDS_OFFS; 141 if (alm->time.tm_min >= 0) 142 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) 143 << RTC_MINUTES_OFFS; 144 if (alm->time.tm_hour >= 0) 145 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) 146 << RTC_HOURS_OFFS; 147 148 writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS); 149 150 if (alm->time.tm_mday >= 0) 151 rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) 152 << RTC_MDAY_OFFS; 153 else 154 rtc_reg = 0; 155 156 if (alm->time.tm_mon >= 0) 157 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) 158 << RTC_MONTH_OFFS; 159 160 if (alm->time.tm_year >= 0) 161 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100)) 162 << RTC_YEAR_OFFS; 163 164 writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS); 165 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 166 writel(alm->enabled ? 1 : 0, 167 ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 168 169 return 0; 170} 171 172static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 173{ 174 struct platform_device *pdev = to_platform_device(dev); 175 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 176 void __iomem *ioaddr = pdata->ioaddr; 177 178 if (pdata->irq < 0) 179 return -EINVAL; /* fall back into rtc-dev's emulation */ 180 181 if (enabled) 182 writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 183 else 184 writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 185 return 0; 186} 187 188static irqreturn_t mv_rtc_interrupt(int irq, void *data) 189{ 190 struct rtc_plat_data *pdata = data; 191 void __iomem *ioaddr = pdata->ioaddr; 192 193 /* alarm irq? */ 194 if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) 195 return IRQ_NONE; 196 197 /* clear interrupt */ 198 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 199 rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); 200 return IRQ_HANDLED; 201} 202 203static const struct rtc_class_ops mv_rtc_ops = { 204 .read_time = mv_rtc_read_time, 205 .set_time = mv_rtc_set_time, 206}; 207 208static const struct rtc_class_ops mv_rtc_alarm_ops = { 209 .read_time = mv_rtc_read_time, 210 .set_time = mv_rtc_set_time, 211 .read_alarm = mv_rtc_read_alarm, 212 .set_alarm = mv_rtc_set_alarm, 213 .alarm_irq_enable = mv_rtc_alarm_irq_enable, 214}; 215 216static int __devinit mv_rtc_probe(struct platform_device *pdev) 217{ 218 struct resource *res; 219 struct rtc_plat_data *pdata; 220 resource_size_t size; 221 u32 rtc_time; 222 223 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 224 if (!res) 225 return -ENODEV; 226 227 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 228 if (!pdata) 229 return -ENOMEM; 230 231 size = resource_size(res); 232 if (!devm_request_mem_region(&pdev->dev, res->start, size, 233 pdev->name)) 234 return -EBUSY; 235 236 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); 237 if (!pdata->ioaddr) 238 return -ENOMEM; 239 240 /* make sure the 24 hours mode is enabled */ 241 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 242 if (rtc_time & RTC_HOURS_12H_MODE) { 243 dev_err(&pdev->dev, "24 Hours mode not supported.\n"); 244 return -EINVAL; 245 } 246 247 /* make sure it is actually functional */ 248 if (rtc_time == 0x01000000) { 249 ssleep(1); 250 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 251 if (rtc_time == 0x01000000) { 252 dev_err(&pdev->dev, "internal RTC not ticking\n"); 253 return -ENODEV; 254 } 255 } 256 257 pdata->irq = platform_get_irq(pdev, 0); 258 259 platform_set_drvdata(pdev, pdata); 260 261 if (pdata->irq >= 0) { 262 device_init_wakeup(&pdev->dev, 1); 263 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 264 &mv_rtc_alarm_ops, 265 THIS_MODULE); 266 } else 267 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 268 &mv_rtc_ops, THIS_MODULE); 269 if (IS_ERR(pdata->rtc)) 270 return PTR_ERR(pdata->rtc); 271 272 if (pdata->irq >= 0) { 273 writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 274 if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt, 275 IRQF_DISABLED | IRQF_SHARED, 276 pdev->name, pdata) < 0) { 277 dev_warn(&pdev->dev, "interrupt not available.\n"); 278 pdata->irq = -1; 279 } 280 } 281 282 return 0; 283} 284 285static int __exit mv_rtc_remove(struct platform_device *pdev) 286{ 287 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 288 289 if (pdata->irq >= 0) 290 device_init_wakeup(&pdev->dev, 0); 291 292 rtc_device_unregister(pdata->rtc); 293 return 0; 294} 295 296static struct platform_driver mv_rtc_driver = { 297 .remove = __exit_p(mv_rtc_remove), 298 .driver = { 299 .name = "rtc-mv", 300 .owner = THIS_MODULE, 301 }, 302}; 303 304static __init int mv_init(void) 305{ 306 return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); 307} 308 309static __exit void mv_exit(void) 310{ 311 platform_driver_unregister(&mv_rtc_driver); 312} 313 314module_init(mv_init); 315module_exit(mv_exit); 316 317MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); 318MODULE_DESCRIPTION("Marvell RTC driver"); 319MODULE_LICENSE("GPL"); 320MODULE_ALIAS("platform:rtc-mv"); 321