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/of.h> 16 #include <linux/delay.h> 17 #include <linux/gfp.h> 18 #include <linux/module.h> 19 20 21 #define RTC_TIME_REG_OFFS 0 22 #define RTC_SECONDS_OFFS 0 23 #define RTC_MINUTES_OFFS 8 24 #define RTC_HOURS_OFFS 16 25 #define RTC_WDAY_OFFS 24 26 #define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ 27 28 #define RTC_DATE_REG_OFFS 4 29 #define RTC_MDAY_OFFS 0 30 #define RTC_MONTH_OFFS 8 31 #define RTC_YEAR_OFFS 16 32 33 #define RTC_ALARM_TIME_REG_OFFS 8 34 #define RTC_ALARM_DATE_REG_OFFS 0xc 35 #define RTC_ALARM_VALID (1 << 7) 36 37 #define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 38 #define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 39 40 struct rtc_plat_data { 41 struct rtc_device *rtc; 42 void __iomem *ioaddr; 43 int irq; 44 }; 45 46 static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) 47 { 48 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 49 void __iomem *ioaddr = pdata->ioaddr; 50 u32 rtc_reg; 51 52 rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | 53 (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | 54 (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | 55 (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); 56 writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); 57 58 rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | 59 (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | 60 (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); 61 writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); 62 63 return 0; 64 } 65 66 static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) 67 { 68 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 69 void __iomem *ioaddr = pdata->ioaddr; 70 u32 rtc_time, rtc_date; 71 unsigned int year, month, day, hour, minute, second, wday; 72 73 rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); 74 rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); 75 76 second = rtc_time & 0x7f; 77 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 78 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 79 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 80 81 day = rtc_date & 0x3f; 82 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 83 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 84 85 tm->tm_sec = bcd2bin(second); 86 tm->tm_min = bcd2bin(minute); 87 tm->tm_hour = bcd2bin(hour); 88 tm->tm_mday = bcd2bin(day); 89 tm->tm_wday = bcd2bin(wday); 90 tm->tm_mon = bcd2bin(month) - 1; 91 /* hw counts from year 2000, but tm_year is relative to 1900 */ 92 tm->tm_year = bcd2bin(year) + 100; 93 94 return rtc_valid_tm(tm); 95 } 96 97 static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 98 { 99 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 100 void __iomem *ioaddr = pdata->ioaddr; 101 u32 rtc_time, rtc_date; 102 unsigned int year, month, day, hour, minute, second, wday; 103 104 rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS); 105 rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS); 106 107 second = rtc_time & 0x7f; 108 minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; 109 hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ 110 wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; 111 112 day = rtc_date & 0x3f; 113 month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; 114 year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; 115 116 alm->time.tm_sec = bcd2bin(second); 117 alm->time.tm_min = bcd2bin(minute); 118 alm->time.tm_hour = bcd2bin(hour); 119 alm->time.tm_mday = bcd2bin(day); 120 alm->time.tm_wday = bcd2bin(wday); 121 alm->time.tm_mon = bcd2bin(month) - 1; 122 /* hw counts from year 2000, but tm_year is relative to 1900 */ 123 alm->time.tm_year = bcd2bin(year) + 100; 124 125 if (rtc_valid_tm(&alm->time) < 0) { 126 dev_err(dev, "retrieved alarm date/time is not valid.\n"); 127 rtc_time_to_tm(0, &alm->time); 128 } 129 130 alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 131 return 0; 132 } 133 134 static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 135 { 136 struct rtc_plat_data *pdata = dev_get_drvdata(dev); 137 void __iomem *ioaddr = pdata->ioaddr; 138 u32 rtc_reg = 0; 139 140 if (alm->time.tm_sec >= 0) 141 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) 142 << RTC_SECONDS_OFFS; 143 if (alm->time.tm_min >= 0) 144 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) 145 << RTC_MINUTES_OFFS; 146 if (alm->time.tm_hour >= 0) 147 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) 148 << RTC_HOURS_OFFS; 149 150 writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS); 151 152 if (alm->time.tm_mday >= 0) 153 rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) 154 << RTC_MDAY_OFFS; 155 else 156 rtc_reg = 0; 157 158 if (alm->time.tm_mon >= 0) 159 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) 160 << RTC_MONTH_OFFS; 161 162 if (alm->time.tm_year >= 0) 163 rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100)) 164 << RTC_YEAR_OFFS; 165 166 writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS); 167 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 168 writel(alm->enabled ? 1 : 0, 169 ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 170 171 return 0; 172 } 173 174 static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 175 { 176 struct platform_device *pdev = to_platform_device(dev); 177 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 178 void __iomem *ioaddr = pdata->ioaddr; 179 180 if (pdata->irq < 0) 181 return -EINVAL; /* fall back into rtc-dev's emulation */ 182 183 if (enabled) 184 writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 185 else 186 writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 187 return 0; 188 } 189 190 static irqreturn_t mv_rtc_interrupt(int irq, void *data) 191 { 192 struct rtc_plat_data *pdata = data; 193 void __iomem *ioaddr = pdata->ioaddr; 194 195 /* alarm irq? */ 196 if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) 197 return IRQ_NONE; 198 199 /* clear interrupt */ 200 writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); 201 rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); 202 return IRQ_HANDLED; 203 } 204 205 static const struct rtc_class_ops mv_rtc_ops = { 206 .read_time = mv_rtc_read_time, 207 .set_time = mv_rtc_set_time, 208 }; 209 210 static const struct rtc_class_ops mv_rtc_alarm_ops = { 211 .read_time = mv_rtc_read_time, 212 .set_time = mv_rtc_set_time, 213 .read_alarm = mv_rtc_read_alarm, 214 .set_alarm = mv_rtc_set_alarm, 215 .alarm_irq_enable = mv_rtc_alarm_irq_enable, 216 }; 217 218 static int __devinit mv_rtc_probe(struct platform_device *pdev) 219 { 220 struct resource *res; 221 struct rtc_plat_data *pdata; 222 resource_size_t size; 223 u32 rtc_time; 224 225 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 226 if (!res) 227 return -ENODEV; 228 229 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 230 if (!pdata) 231 return -ENOMEM; 232 233 size = resource_size(res); 234 if (!devm_request_mem_region(&pdev->dev, res->start, size, 235 pdev->name)) 236 return -EBUSY; 237 238 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); 239 if (!pdata->ioaddr) 240 return -ENOMEM; 241 242 /* make sure the 24 hours mode is enabled */ 243 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 244 if (rtc_time & RTC_HOURS_12H_MODE) { 245 dev_err(&pdev->dev, "24 Hours mode not supported.\n"); 246 return -EINVAL; 247 } 248 249 /* make sure it is actually functional */ 250 if (rtc_time == 0x01000000) { 251 ssleep(1); 252 rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); 253 if (rtc_time == 0x01000000) { 254 dev_err(&pdev->dev, "internal RTC not ticking\n"); 255 return -ENODEV; 256 } 257 } 258 259 pdata->irq = platform_get_irq(pdev, 0); 260 261 platform_set_drvdata(pdev, pdata); 262 263 if (pdata->irq >= 0) { 264 device_init_wakeup(&pdev->dev, 1); 265 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 266 &mv_rtc_alarm_ops, 267 THIS_MODULE); 268 } else 269 pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, 270 &mv_rtc_ops, THIS_MODULE); 271 if (IS_ERR(pdata->rtc)) 272 return PTR_ERR(pdata->rtc); 273 274 if (pdata->irq >= 0) { 275 writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); 276 if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt, 277 IRQF_SHARED, 278 pdev->name, pdata) < 0) { 279 dev_warn(&pdev->dev, "interrupt not available.\n"); 280 pdata->irq = -1; 281 } 282 } 283 284 return 0; 285 } 286 287 static int __exit mv_rtc_remove(struct platform_device *pdev) 288 { 289 struct rtc_plat_data *pdata = platform_get_drvdata(pdev); 290 291 if (pdata->irq >= 0) 292 device_init_wakeup(&pdev->dev, 0); 293 294 rtc_device_unregister(pdata->rtc); 295 return 0; 296 } 297 298 #ifdef CONFIG_OF 299 static struct of_device_id rtc_mv_of_match_table[] = { 300 { .compatible = "marvell,orion-rtc", }, 301 {} 302 }; 303 #endif 304 305 static struct platform_driver mv_rtc_driver = { 306 .remove = __exit_p(mv_rtc_remove), 307 .driver = { 308 .name = "rtc-mv", 309 .owner = THIS_MODULE, 310 .of_match_table = of_match_ptr(rtc_mv_of_match_table), 311 }, 312 }; 313 314 static __init int mv_init(void) 315 { 316 return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); 317 } 318 319 static __exit void mv_exit(void) 320 { 321 platform_driver_unregister(&mv_rtc_driver); 322 } 323 324 module_init(mv_init); 325 module_exit(mv_exit); 326 327 MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); 328 MODULE_DESCRIPTION("Marvell RTC driver"); 329 MODULE_LICENSE("GPL"); 330 MODULE_ALIAS("platform:rtc-mv"); 331