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 17 18 #define RTC_TIME_REG_OFFS 0 19 #define RTC_SECONDS_OFFS 0 20 #define RTC_MINUTES_OFFS 8 21 #define RTC_HOURS_OFFS 16 22 #define RTC_WDAY_OFFS 24 23 #define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ 24 25 #define RTC_DATE_REG_OFFS 4 26 #define RTC_MDAY_OFFS 0 27 #define RTC_MONTH_OFFS 8 28 #define RTC_YEAR_OFFS 16 29 30 #define RTC_ALARM_TIME_REG_OFFS 8 31 #define RTC_ALARM_DATE_REG_OFFS 0xc 32 #define RTC_ALARM_VALID (1 << 7) 33 34 #define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 35 #define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 36 37 struct rtc_plat_data { 38 struct rtc_device *rtc; 39 void __iomem *ioaddr; 40 int irq; 41 }; 42 43 static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) 44 { 45 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 46 void __iomem *ioaddr = pdata->ioaddr; 47 u32 rtc_reg; 48 49 rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | 50 (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | 51 (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | 52 (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); 53 writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); 54 55 rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | 56 (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | 57 (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); 58 writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); 59 60 return 0; 61 } 62 63 static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) 64 { 65 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 66 void __iomem *ioaddr = pdata->ioaddr; 67 u32 rtc_time, rtc_date; 68 unsigned int year, month, day, hour, minute, second, wday; 69 70 rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); 71 rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); 72 73 second = rtc_time & 0x7f; 74 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 75 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 76 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 77 78 day = rtc_date & 0x3f; 79 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 80 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 81 82 tm->tm_sec = bcd2bin(second); 83 tm->tm_min = bcd2bin(minute); 84 tm->tm_hour = bcd2bin(hour); 85 tm->tm_mday = bcd2bin(day); 86 tm->tm_wday = bcd2bin(wday); 87 tm->tm_mon = bcd2bin(month) - 1; 88 /* hw counts from year 2000, but tm_year is relative to 1900 */ 89 tm->tm_year = bcd2bin(year) + 100; 90 91 return rtc_valid_tm(tm); 92 } 93 94 static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 95 { 96 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 97 void __iomem *ioaddr = pdata->ioaddr; 98 u32 rtc_time, rtc_date; 99 unsigned int year, month, day, hour, minute, second, wday; 100 101 rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS); 102 rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS); 103 104 second = rtc_time & 0x7f; 105 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 106 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 107 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 108 109 day = rtc_date & 0x3f; 110 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 111 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 112 113 alm->time.tm_sec = bcd2bin(second); 114 alm->time.tm_min = bcd2bin(minute); 115 alm->time.tm_hour = bcd2bin(hour); 116 alm->time.tm_mday = bcd2bin(day); 117 alm->time.tm_wday = bcd2bin(wday); 118 alm->time.tm_mon = bcd2bin(month) - 1; 119 /* hw counts from year 2000, but tm_year is relative to 1900 */ 120 alm->time.tm_year = bcd2bin(year) + 100; 121 122 if (rtc_valid_tm(&alm->time) < 0) { 123 dev_err(dev, "retrieved alarm date/time is not valid.\n"); 124 rtc_time_to_tm(0, &alm->time); 125 } 126 127 alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 128 return 0; 129 } 130 131 static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 132 { 133 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 134 void __iomem *ioaddr = pdata->ioaddr; 135 u32 rtc_reg = 0; 136 137 if (alm->time.tm_sec >= 0) 138 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) 139 << RTC_SECONDS_OFFS; 140 if (alm->time.tm_min >= 0) 141 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) 142 << RTC_MINUTES_OFFS; 143 if (alm->time.tm_hour >= 0) 144 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) 145 << RTC_HOURS_OFFS; 146 147 writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS); 148 149 if (alm->time.tm_mday >= 0) 150 rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) 151 << RTC_MDAY_OFFS; 152 else 153 rtc_reg = 0; 154 155 if (alm->time.tm_mon >= 0) 156 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) 157 << RTC_MONTH_OFFS; 158 159 if (alm->time.tm_year >= 0) 160 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100)) 161 << RTC_YEAR_OFFS; 162 163 writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS); 164 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 165 writel(alm->enabled ? 1 : 0, 166 ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 167 168 return 0; 169 } 170 171 static int mv_rtc_ioctl(struct device *dev, unsigned int cmd, 172 unsigned long arg) 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 -ENOIOCTLCMD; /* fall back into rtc-dev's emulation */ 180 switch (cmd) { 181 case RTC_AIE_OFF: 182 writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 183 break; 184 case RTC_AIE_ON: 185 writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 186 break; 187 default: 188 return -ENOIOCTLCMD; 189 } 190 return 0; 191 } 192 193 static irqreturn_t mv_rtc_interrupt(int irq, void *data) 194 { 195 struct rtc_plat_data *pdata = data; 196 void __iomem *ioaddr = pdata->ioaddr; 197 198 /* alarm irq? */ 199 if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) 200 return IRQ_NONE; 201 202 /* clear interrupt */ 203 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 204 rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); 205 return IRQ_HANDLED; 206 } 207 208 static const struct rtc_class_ops mv_rtc_ops = { 209 .read_time = mv_rtc_read_time, 210 .set_time = mv_rtc_set_time, 211 }; 212 213 static const struct rtc_class_ops mv_rtc_alarm_ops = { 214 .read_time = mv_rtc_read_time, 215 .set_time = mv_rtc_set_time, 216 .read_alarm = mv_rtc_read_alarm, 217 .set_alarm = mv_rtc_set_alarm, 218 .ioctl = mv_rtc_ioctl, 219 }; 220 221 static int __devinit mv_rtc_probe(struct platform_device *pdev) 222 { 223 struct resource *res; 224 struct rtc_plat_data *pdata; 225 resource_size_t size; 226 u32 rtc_time; 227 228 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 229 if (!res) 230 return -ENODEV; 231 232 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 233 if (!pdata) 234 return -ENOMEM; 235 236 size = resource_size(res); 237 if (!devm_request_mem_region(&pdev->dev, res->start, size, 238 pdev->name)) 239 return -EBUSY; 240 241 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); 242 if (!pdata->ioaddr) 243 return -ENOMEM; 244 245 /* make sure the 24 hours mode is enabled */ 246 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 247 if (rtc_time & RTC_HOURS_12H_MODE) { 248 dev_err(&pdev->dev, "24 Hours mode not supported.\n"); 249 return -EINVAL; 250 } 251 252 /* make sure it is actually functional */ 253 if (rtc_time == 0x01000000) { 254 ssleep(1); 255 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 256 if (rtc_time == 0x01000000) { 257 dev_err(&pdev->dev, "internal RTC not ticking\n"); 258 return -ENODEV; 259 } 260 } 261 262 pdata->irq = platform_get_irq(pdev, 0); 263 264 platform_set_drvdata(pdev, pdata); 265 266 if (pdata->irq >= 0) { 267 device_init_wakeup(&pdev->dev, 1); 268 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 269 &mv_rtc_alarm_ops, 270 THIS_MODULE); 271 } else 272 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 273 &mv_rtc_ops, THIS_MODULE); 274 if (IS_ERR(pdata->rtc)) 275 return PTR_ERR(pdata->rtc); 276 277 if (pdata->irq >= 0) { 278 writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 279 if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt, 280 IRQF_DISABLED | IRQF_SHARED, 281 pdev->name, pdata) < 0) { 282 dev_warn(&pdev->dev, "interrupt not available.\n"); 283 pdata->irq = -1; 284 } 285 } 286 287 return 0; 288 } 289 290 static int __exit mv_rtc_remove(struct platform_device *pdev) 291 { 292 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 293 294 if (pdata->irq >= 0) 295 device_init_wakeup(&pdev->dev, 0); 296 297 rtc_device_unregister(pdata->rtc); 298 return 0; 299 } 300 301 static struct platform_driver mv_rtc_driver = { 302 .remove = __exit_p(mv_rtc_remove), 303 .driver = { 304 .name = "rtc-mv", 305 .owner = THIS_MODULE, 306 }, 307 }; 308 309 static __init int mv_init(void) 310 { 311 return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); 312 } 313 314 static __exit void mv_exit(void) 315 { 316 platform_driver_unregister(&mv_rtc_driver); 317 } 318 319 module_init(mv_init); 320 module_exit(mv_exit); 321 322 MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); 323 MODULE_DESCRIPTION("Marvell RTC driver"); 324 MODULE_LICENSE("GPL"); 325 MODULE_ALIAS("platform:rtc-mv"); 326