rtc-mv.c revision 2113852b239ed4a93d04135372162252f9342bb6
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#include <linux/module.h> 18 19 20#define RTC_TIME_REG_OFFS 0 21#define RTC_SECONDS_OFFS 0 22#define RTC_MINUTES_OFFS 8 23#define RTC_HOURS_OFFS 16 24#define RTC_WDAY_OFFS 24 25#define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ 26 27#define RTC_DATE_REG_OFFS 4 28#define RTC_MDAY_OFFS 0 29#define RTC_MONTH_OFFS 8 30#define RTC_YEAR_OFFS 16 31 32#define RTC_ALARM_TIME_REG_OFFS 8 33#define RTC_ALARM_DATE_REG_OFFS 0xc 34#define RTC_ALARM_VALID (1 << 7) 35 36#define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 37#define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 38 39struct rtc_plat_data { 40 struct rtc_device *rtc; 41 void __iomem *ioaddr; 42 int irq; 43}; 44 45static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) 46{ 47 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 48 void __iomem *ioaddr = pdata->ioaddr; 49 u32 rtc_reg; 50 51 rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | 52 (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | 53 (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | 54 (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); 55 writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); 56 57 rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | 58 (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | 59 (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); 60 writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); 61 62 return 0; 63} 64 65static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) 66{ 67 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 68 void __iomem *ioaddr = pdata->ioaddr; 69 u32 rtc_time, rtc_date; 70 unsigned int year, month, day, hour, minute, second, wday; 71 72 rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); 73 rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); 74 75 second = rtc_time & 0x7f; 76 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 77 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 78 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 79 80 day = rtc_date & 0x3f; 81 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 82 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 83 84 tm->tm_sec = bcd2bin(second); 85 tm->tm_min = bcd2bin(minute); 86 tm->tm_hour = bcd2bin(hour); 87 tm->tm_mday = bcd2bin(day); 88 tm->tm_wday = bcd2bin(wday); 89 tm->tm_mon = bcd2bin(month) - 1; 90 /* hw counts from year 2000, but tm_year is relative to 1900 */ 91 tm->tm_year = bcd2bin(year) + 100; 92 93 return rtc_valid_tm(tm); 94} 95 96static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 97{ 98 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 99 void __iomem *ioaddr = pdata->ioaddr; 100 u32 rtc_time, rtc_date; 101 unsigned int year, month, day, hour, minute, second, wday; 102 103 rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS); 104 rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS); 105 106 second = rtc_time & 0x7f; 107 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 108 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 109 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 110 111 day = rtc_date & 0x3f; 112 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 113 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 114 115 alm->time.tm_sec = bcd2bin(second); 116 alm->time.tm_min = bcd2bin(minute); 117 alm->time.tm_hour = bcd2bin(hour); 118 alm->time.tm_mday = bcd2bin(day); 119 alm->time.tm_wday = bcd2bin(wday); 120 alm->time.tm_mon = bcd2bin(month) - 1; 121 /* hw counts from year 2000, but tm_year is relative to 1900 */ 122 alm->time.tm_year = bcd2bin(year) + 100; 123 124 if (rtc_valid_tm(&alm->time) < 0) { 125 dev_err(dev, "retrieved alarm date/time is not valid.\n"); 126 rtc_time_to_tm(0, &alm->time); 127 } 128 129 alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 130 return 0; 131} 132 133static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 134{ 135 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 136 void __iomem *ioaddr = pdata->ioaddr; 137 u32 rtc_reg = 0; 138 139 if (alm->time.tm_sec >= 0) 140 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) 141 << RTC_SECONDS_OFFS; 142 if (alm->time.tm_min >= 0) 143 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) 144 << RTC_MINUTES_OFFS; 145 if (alm->time.tm_hour >= 0) 146 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) 147 << RTC_HOURS_OFFS; 148 149 writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS); 150 151 if (alm->time.tm_mday >= 0) 152 rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) 153 << RTC_MDAY_OFFS; 154 else 155 rtc_reg = 0; 156 157 if (alm->time.tm_mon >= 0) 158 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) 159 << RTC_MONTH_OFFS; 160 161 if (alm->time.tm_year >= 0) 162 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100)) 163 << RTC_YEAR_OFFS; 164 165 writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS); 166 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 167 writel(alm->enabled ? 1 : 0, 168 ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 169 170 return 0; 171} 172 173static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 174{ 175 struct platform_device *pdev = to_platform_device(dev); 176 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 177 void __iomem *ioaddr = pdata->ioaddr; 178 179 if (pdata->irq < 0) 180 return -EINVAL; /* fall back into rtc-dev's emulation */ 181 182 if (enabled) 183 writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 184 else 185 writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 186 return 0; 187} 188 189static irqreturn_t mv_rtc_interrupt(int irq, void *data) 190{ 191 struct rtc_plat_data *pdata = data; 192 void __iomem *ioaddr = pdata->ioaddr; 193 194 /* alarm irq? */ 195 if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) 196 return IRQ_NONE; 197 198 /* clear interrupt */ 199 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 200 rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); 201 return IRQ_HANDLED; 202} 203 204static const struct rtc_class_ops mv_rtc_ops = { 205 .read_time = mv_rtc_read_time, 206 .set_time = mv_rtc_set_time, 207}; 208 209static const struct rtc_class_ops mv_rtc_alarm_ops = { 210 .read_time = mv_rtc_read_time, 211 .set_time = mv_rtc_set_time, 212 .read_alarm = mv_rtc_read_alarm, 213 .set_alarm = mv_rtc_set_alarm, 214 .alarm_irq_enable = mv_rtc_alarm_irq_enable, 215}; 216 217static int __devinit mv_rtc_probe(struct platform_device *pdev) 218{ 219 struct resource *res; 220 struct rtc_plat_data *pdata; 221 resource_size_t size; 222 u32 rtc_time; 223 224 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 225 if (!res) 226 return -ENODEV; 227 228 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 229 if (!pdata) 230 return -ENOMEM; 231 232 size = resource_size(res); 233 if (!devm_request_mem_region(&pdev->dev, res->start, size, 234 pdev->name)) 235 return -EBUSY; 236 237 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); 238 if (!pdata->ioaddr) 239 return -ENOMEM; 240 241 /* make sure the 24 hours mode is enabled */ 242 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 243 if (rtc_time & RTC_HOURS_12H_MODE) { 244 dev_err(&pdev->dev, "24 Hours mode not supported.\n"); 245 return -EINVAL; 246 } 247 248 /* make sure it is actually functional */ 249 if (rtc_time == 0x01000000) { 250 ssleep(1); 251 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 252 if (rtc_time == 0x01000000) { 253 dev_err(&pdev->dev, "internal RTC not ticking\n"); 254 return -ENODEV; 255 } 256 } 257 258 pdata->irq = platform_get_irq(pdev, 0); 259 260 platform_set_drvdata(pdev, pdata); 261 262 if (pdata->irq >= 0) { 263 device_init_wakeup(&pdev->dev, 1); 264 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 265 &mv_rtc_alarm_ops, 266 THIS_MODULE); 267 } else 268 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 269 &mv_rtc_ops, THIS_MODULE); 270 if (IS_ERR(pdata->rtc)) 271 return PTR_ERR(pdata->rtc); 272 273 if (pdata->irq >= 0) { 274 writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 275 if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt, 276 IRQF_DISABLED | IRQF_SHARED, 277 pdev->name, pdata) < 0) { 278 dev_warn(&pdev->dev, "interrupt not available.\n"); 279 pdata->irq = -1; 280 } 281 } 282 283 return 0; 284} 285 286static int __exit mv_rtc_remove(struct platform_device *pdev) 287{ 288 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 289 290 if (pdata->irq >= 0) 291 device_init_wakeup(&pdev->dev, 0); 292 293 rtc_device_unregister(pdata->rtc); 294 return 0; 295} 296 297static struct platform_driver mv_rtc_driver = { 298 .remove = __exit_p(mv_rtc_remove), 299 .driver = { 300 .name = "rtc-mv", 301 .owner = THIS_MODULE, 302 }, 303}; 304 305static __init int mv_init(void) 306{ 307 return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); 308} 309 310static __exit void mv_exit(void) 311{ 312 platform_driver_unregister(&mv_rtc_driver); 313} 314 315module_init(mv_init); 316module_exit(mv_exit); 317 318MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); 319MODULE_DESCRIPTION("Marvell RTC driver"); 320MODULE_LICENSE("GPL"); 321MODULE_ALIAS("platform:rtc-mv"); 322