1/* 2 * TX4939 internal RTC driver 3 * Based on RBTX49xx patch from CELF patch archive. 4 * 5 * This file is subject to the terms and conditions of the GNU General Public 6 * License. See the file "COPYING" in the main directory of this archive 7 * for more details. 8 * 9 * (C) Copyright TOSHIBA CORPORATION 2005-2007 10 */ 11#include <linux/rtc.h> 12#include <linux/platform_device.h> 13#include <linux/interrupt.h> 14#include <linux/io.h> 15#include <linux/gfp.h> 16#include <asm/txx9/tx4939.h> 17 18struct tx4939rtc_plat_data { 19 struct rtc_device *rtc; 20 struct tx4939_rtc_reg __iomem *rtcreg; 21 spinlock_t lock; 22}; 23 24static struct tx4939rtc_plat_data *get_tx4939rtc_plat_data(struct device *dev) 25{ 26 return platform_get_drvdata(to_platform_device(dev)); 27} 28 29static int tx4939_rtc_cmd(struct tx4939_rtc_reg __iomem *rtcreg, int cmd) 30{ 31 int i = 0; 32 33 __raw_writel(cmd, &rtcreg->ctl); 34 /* This might take 30us (next 32.768KHz clock) */ 35 while (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_BUSY) { 36 /* timeout on approx. 100us (@ GBUS200MHz) */ 37 if (i++ > 200 * 100) 38 return -EBUSY; 39 cpu_relax(); 40 } 41 return 0; 42} 43 44static int tx4939_rtc_set_mmss(struct device *dev, unsigned long secs) 45{ 46 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 47 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 48 int i, ret; 49 unsigned char buf[6]; 50 51 buf[0] = 0; 52 buf[1] = 0; 53 buf[2] = secs; 54 buf[3] = secs >> 8; 55 buf[4] = secs >> 16; 56 buf[5] = secs >> 24; 57 spin_lock_irq(&pdata->lock); 58 __raw_writel(0, &rtcreg->adr); 59 for (i = 0; i < 6; i++) 60 __raw_writel(buf[i], &rtcreg->dat); 61 ret = tx4939_rtc_cmd(rtcreg, 62 TX4939_RTCCTL_COMMAND_SETTIME | 63 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); 64 spin_unlock_irq(&pdata->lock); 65 return ret; 66} 67 68static int tx4939_rtc_read_time(struct device *dev, struct rtc_time *tm) 69{ 70 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 71 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 72 int i, ret; 73 unsigned long sec; 74 unsigned char buf[6]; 75 76 spin_lock_irq(&pdata->lock); 77 ret = tx4939_rtc_cmd(rtcreg, 78 TX4939_RTCCTL_COMMAND_GETTIME | 79 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); 80 if (ret) { 81 spin_unlock_irq(&pdata->lock); 82 return ret; 83 } 84 __raw_writel(2, &rtcreg->adr); 85 for (i = 2; i < 6; i++) 86 buf[i] = __raw_readl(&rtcreg->dat); 87 spin_unlock_irq(&pdata->lock); 88 sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2]; 89 rtc_time_to_tm(sec, tm); 90 return rtc_valid_tm(tm); 91} 92 93static int tx4939_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 94{ 95 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 96 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 97 int i, ret; 98 unsigned long sec; 99 unsigned char buf[6]; 100 101 if (alrm->time.tm_sec < 0 || 102 alrm->time.tm_min < 0 || 103 alrm->time.tm_hour < 0 || 104 alrm->time.tm_mday < 0 || 105 alrm->time.tm_mon < 0 || 106 alrm->time.tm_year < 0) 107 return -EINVAL; 108 rtc_tm_to_time(&alrm->time, &sec); 109 buf[0] = 0; 110 buf[1] = 0; 111 buf[2] = sec; 112 buf[3] = sec >> 8; 113 buf[4] = sec >> 16; 114 buf[5] = sec >> 24; 115 spin_lock_irq(&pdata->lock); 116 __raw_writel(0, &rtcreg->adr); 117 for (i = 0; i < 6; i++) 118 __raw_writel(buf[i], &rtcreg->dat); 119 ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_SETALARM | 120 (alrm->enabled ? TX4939_RTCCTL_ALME : 0)); 121 spin_unlock_irq(&pdata->lock); 122 return ret; 123} 124 125static int tx4939_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) 126{ 127 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 128 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 129 int i, ret; 130 unsigned long sec; 131 unsigned char buf[6]; 132 u32 ctl; 133 134 spin_lock_irq(&pdata->lock); 135 ret = tx4939_rtc_cmd(rtcreg, 136 TX4939_RTCCTL_COMMAND_GETALARM | 137 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); 138 if (ret) { 139 spin_unlock_irq(&pdata->lock); 140 return ret; 141 } 142 __raw_writel(2, &rtcreg->adr); 143 for (i = 2; i < 6; i++) 144 buf[i] = __raw_readl(&rtcreg->dat); 145 ctl = __raw_readl(&rtcreg->ctl); 146 alrm->enabled = (ctl & TX4939_RTCCTL_ALME) ? 1 : 0; 147 alrm->pending = (ctl & TX4939_RTCCTL_ALMD) ? 1 : 0; 148 spin_unlock_irq(&pdata->lock); 149 sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2]; 150 rtc_time_to_tm(sec, &alrm->time); 151 return rtc_valid_tm(&alrm->time); 152} 153 154static int tx4939_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 155{ 156 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 157 158 spin_lock_irq(&pdata->lock); 159 tx4939_rtc_cmd(pdata->rtcreg, 160 TX4939_RTCCTL_COMMAND_NOP | 161 (enabled ? TX4939_RTCCTL_ALME : 0)); 162 spin_unlock_irq(&pdata->lock); 163 return 0; 164} 165 166static irqreturn_t tx4939_rtc_interrupt(int irq, void *dev_id) 167{ 168 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev_id); 169 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 170 unsigned long events = RTC_IRQF; 171 172 spin_lock(&pdata->lock); 173 if (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALMD) { 174 events |= RTC_AF; 175 tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_NOP); 176 } 177 spin_unlock(&pdata->lock); 178 if (likely(pdata->rtc)) 179 rtc_update_irq(pdata->rtc, 1, events); 180 return IRQ_HANDLED; 181} 182 183static const struct rtc_class_ops tx4939_rtc_ops = { 184 .read_time = tx4939_rtc_read_time, 185 .read_alarm = tx4939_rtc_read_alarm, 186 .set_alarm = tx4939_rtc_set_alarm, 187 .set_mmss = tx4939_rtc_set_mmss, 188 .alarm_irq_enable = tx4939_rtc_alarm_irq_enable, 189}; 190 191static ssize_t tx4939_rtc_nvram_read(struct file *filp, struct kobject *kobj, 192 struct bin_attribute *bin_attr, 193 char *buf, loff_t pos, size_t size) 194{ 195 struct device *dev = container_of(kobj, struct device, kobj); 196 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 197 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 198 ssize_t count; 199 200 spin_lock_irq(&pdata->lock); 201 for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE; 202 count++, size--) { 203 __raw_writel(pos++, &rtcreg->adr); 204 *buf++ = __raw_readl(&rtcreg->dat); 205 } 206 spin_unlock_irq(&pdata->lock); 207 return count; 208} 209 210static ssize_t tx4939_rtc_nvram_write(struct file *filp, struct kobject *kobj, 211 struct bin_attribute *bin_attr, 212 char *buf, loff_t pos, size_t size) 213{ 214 struct device *dev = container_of(kobj, struct device, kobj); 215 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); 216 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; 217 ssize_t count; 218 219 spin_lock_irq(&pdata->lock); 220 for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE; 221 count++, size--) { 222 __raw_writel(pos++, &rtcreg->adr); 223 __raw_writel(*buf++, &rtcreg->dat); 224 } 225 spin_unlock_irq(&pdata->lock); 226 return count; 227} 228 229static struct bin_attribute tx4939_rtc_nvram_attr = { 230 .attr = { 231 .name = "nvram", 232 .mode = S_IRUGO | S_IWUSR, 233 }, 234 .size = TX4939_RTC_REG_RAMSIZE, 235 .read = tx4939_rtc_nvram_read, 236 .write = tx4939_rtc_nvram_write, 237}; 238 239static int __init tx4939_rtc_probe(struct platform_device *pdev) 240{ 241 struct rtc_device *rtc; 242 struct tx4939rtc_plat_data *pdata; 243 struct resource *res; 244 int irq, ret; 245 246 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 247 if (!res) 248 return -ENODEV; 249 irq = platform_get_irq(pdev, 0); 250 if (irq < 0) 251 return -ENODEV; 252 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 253 if (!pdata) 254 return -ENOMEM; 255 platform_set_drvdata(pdev, pdata); 256 257 if (!devm_request_mem_region(&pdev->dev, res->start, 258 resource_size(res), pdev->name)) 259 return -EBUSY; 260 pdata->rtcreg = devm_ioremap(&pdev->dev, res->start, 261 resource_size(res)); 262 if (!pdata->rtcreg) 263 return -EBUSY; 264 265 spin_lock_init(&pdata->lock); 266 tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); 267 if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt, 268 IRQF_DISABLED, pdev->name, &pdev->dev) < 0) 269 return -EBUSY; 270 rtc = rtc_device_register(pdev->name, &pdev->dev, 271 &tx4939_rtc_ops, THIS_MODULE); 272 if (IS_ERR(rtc)) 273 return PTR_ERR(rtc); 274 pdata->rtc = rtc; 275 ret = sysfs_create_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr); 276 if (ret) 277 rtc_device_unregister(rtc); 278 return ret; 279} 280 281static int __exit tx4939_rtc_remove(struct platform_device *pdev) 282{ 283 struct tx4939rtc_plat_data *pdata = platform_get_drvdata(pdev); 284 285 sysfs_remove_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr); 286 rtc_device_unregister(pdata->rtc); 287 spin_lock_irq(&pdata->lock); 288 tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); 289 spin_unlock_irq(&pdata->lock); 290 return 0; 291} 292 293static struct platform_driver tx4939_rtc_driver = { 294 .remove = __exit_p(tx4939_rtc_remove), 295 .driver = { 296 .name = "tx4939rtc", 297 .owner = THIS_MODULE, 298 }, 299}; 300 301static int __init tx4939rtc_init(void) 302{ 303 return platform_driver_probe(&tx4939_rtc_driver, tx4939_rtc_probe); 304} 305 306static void __exit tx4939rtc_exit(void) 307{ 308 platform_driver_unregister(&tx4939_rtc_driver); 309} 310 311module_init(tx4939rtc_init); 312module_exit(tx4939rtc_exit); 313 314MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>"); 315MODULE_DESCRIPTION("TX4939 internal RTC driver"); 316MODULE_LICENSE("GPL"); 317MODULE_ALIAS("platform:tx4939rtc"); 318