diff options
| author | Haavard Skinnemoen <haavard.skinnemoen@atmel.com> | 2009-10-06 11:36:55 -0400 |
|---|---|---|
| committer | Haavard Skinnemoen <haavard.skinnemoen@atmel.com> | 2009-10-06 11:36:55 -0400 |
| commit | d94e5fcbf1420366dcb4102bafe04dbcfc0d0d4b (patch) | |
| tree | a9b7de7df6da5c3132cc68169b9c47ba288ccd42 /drivers/rtc/rtc-pcf2123.c | |
| parent | d55651168a20078a94597a297d5cdfd807bf07b6 (diff) | |
| parent | 374576a8b6f865022c0fd1ca62396889b23d66dd (diff) | |
Merge commit 'v2.6.32-rc3'
Diffstat (limited to 'drivers/rtc/rtc-pcf2123.c')
| -rw-r--r-- | drivers/rtc/rtc-pcf2123.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pcf2123.c b/drivers/rtc/rtc-pcf2123.c new file mode 100644 index 000000000000..e75df9d50e27 --- /dev/null +++ b/drivers/rtc/rtc-pcf2123.c | |||
| @@ -0,0 +1,364 @@ | |||
| 1 | /* | ||
| 2 | * An SPI driver for the Philips PCF2123 RTC | ||
| 3 | * Copyright 2009 Cyber Switching, Inc. | ||
| 4 | * | ||
| 5 | * Author: Chris Verges <chrisv@cyberswitching.com> | ||
| 6 | * Maintainers: http://www.cyberswitching.com | ||
| 7 | * | ||
| 8 | * based on the RS5C348 driver in this same directory. | ||
| 9 | * | ||
| 10 | * Thanks to Christian Pellegrin <chripell@fsfe.org> for | ||
| 11 | * the sysfs contributions to this driver. | ||
| 12 | * | ||
| 13 | * This program is free software; you can redistribute it and/or modify | ||
| 14 | * it under the terms of the GNU General Public License version 2 as | ||
| 15 | * published by the Free Software Foundation. | ||
| 16 | * | ||
| 17 | * Please note that the CS is active high, so platform data | ||
| 18 | * should look something like: | ||
| 19 | * | ||
| 20 | * static struct spi_board_info ek_spi_devices[] = { | ||
| 21 | * ... | ||
| 22 | * { | ||
| 23 | * .modalias = "rtc-pcf2123", | ||
| 24 | * .chip_select = 1, | ||
| 25 | * .controller_data = (void *)AT91_PIN_PA10, | ||
| 26 | * .max_speed_hz = 1000 * 1000, | ||
| 27 | * .mode = SPI_CS_HIGH, | ||
| 28 | * .bus_num = 0, | ||
| 29 | * }, | ||
| 30 | * ... | ||
| 31 | *}; | ||
| 32 | * | ||
| 33 | */ | ||
| 34 | |||
| 35 | #include <linux/bcd.h> | ||
| 36 | #include <linux/delay.h> | ||
| 37 | #include <linux/device.h> | ||
| 38 | #include <linux/errno.h> | ||
| 39 | #include <linux/init.h> | ||
| 40 | #include <linux/kernel.h> | ||
| 41 | #include <linux/string.h> | ||
| 42 | #include <linux/rtc.h> | ||
| 43 | #include <linux/spi/spi.h> | ||
| 44 | |||
| 45 | #define DRV_VERSION "0.6" | ||
| 46 | |||
| 47 | #define PCF2123_REG_CTRL1 (0x00) /* Control Register 1 */ | ||
| 48 | #define PCF2123_REG_CTRL2 (0x01) /* Control Register 2 */ | ||
| 49 | #define PCF2123_REG_SC (0x02) /* datetime */ | ||
| 50 | #define PCF2123_REG_MN (0x03) | ||
| 51 | #define PCF2123_REG_HR (0x04) | ||
| 52 | #define PCF2123_REG_DM (0x05) | ||
| 53 | #define PCF2123_REG_DW (0x06) | ||
| 54 | #define PCF2123_REG_MO (0x07) | ||
| 55 | #define PCF2123_REG_YR (0x08) | ||
| 56 | |||
| 57 | #define PCF2123_SUBADDR (1 << 4) | ||
| 58 | #define PCF2123_WRITE ((0 << 7) | PCF2123_SUBADDR) | ||
| 59 | #define PCF2123_READ ((1 << 7) | PCF2123_SUBADDR) | ||
| 60 | |||
| 61 | static struct spi_driver pcf2123_driver; | ||
| 62 | |||
| 63 | struct pcf2123_sysfs_reg { | ||
| 64 | struct device_attribute attr; | ||
| 65 | char name[2]; | ||
| 66 | }; | ||
| 67 | |||
| 68 | struct pcf2123_plat_data { | ||
| 69 | struct rtc_device *rtc; | ||
| 70 | struct pcf2123_sysfs_reg regs[16]; | ||
| 71 | }; | ||
| 72 | |||
| 73 | /* | ||
| 74 | * Causes a 30 nanosecond delay to ensure that the PCF2123 chip select | ||
| 75 | * is released properly after an SPI write. This function should be | ||
| 76 | * called after EVERY read/write call over SPI. | ||
| 77 | */ | ||
| 78 | static inline void pcf2123_delay_trec(void) | ||
| 79 | { | ||
| 80 | ndelay(30); | ||
| 81 | } | ||
| 82 | |||
| 83 | static ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr, | ||
| 84 | char *buffer) | ||
| 85 | { | ||
| 86 | struct spi_device *spi = to_spi_device(dev); | ||
| 87 | struct pcf2123_sysfs_reg *r; | ||
| 88 | u8 txbuf[1], rxbuf[1]; | ||
| 89 | unsigned long reg; | ||
| 90 | int ret; | ||
| 91 | |||
| 92 | r = container_of(attr, struct pcf2123_sysfs_reg, attr); | ||
| 93 | |||
| 94 | if (strict_strtoul(r->name, 16, ®)) | ||
| 95 | return -EINVAL; | ||
| 96 | |||
| 97 | txbuf[0] = PCF2123_READ | reg; | ||
| 98 | ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1); | ||
| 99 | if (ret < 0) | ||
| 100 | return -EIO; | ||
| 101 | pcf2123_delay_trec(); | ||
| 102 | return sprintf(buffer, "0x%x\n", rxbuf[0]); | ||
| 103 | } | ||
| 104 | |||
| 105 | static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr, | ||
| 106 | const char *buffer, size_t count) { | ||
| 107 | struct spi_device *spi = to_spi_device(dev); | ||
| 108 | struct pcf2123_sysfs_reg *r; | ||
| 109 | u8 txbuf[2]; | ||
| 110 | unsigned long reg; | ||
| 111 | unsigned long val; | ||
| 112 | |||
| 113 | int ret; | ||
| 114 | |||
| 115 | r = container_of(attr, struct pcf2123_sysfs_reg, attr); | ||
| 116 | |||
| 117 | if (strict_strtoul(r->name, 16, ®) | ||
| 118 | || strict_strtoul(buffer, 10, &val)) | ||
| 119 | return -EINVAL; | ||
| 120 | |||
| 121 | txbuf[0] = PCF2123_WRITE | reg; | ||
| 122 | txbuf[1] = val; | ||
| 123 | ret = spi_write(spi, txbuf, sizeof(txbuf)); | ||
| 124 | if (ret < 0) | ||
| 125 | return -EIO; | ||
| 126 | pcf2123_delay_trec(); | ||
| 127 | return count; | ||
| 128 | } | ||
| 129 | |||
| 130 | static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm) | ||
| 131 | { | ||
| 132 | struct spi_device *spi = to_spi_device(dev); | ||
| 133 | u8 txbuf[1], rxbuf[7]; | ||
| 134 | int ret; | ||
| 135 | |||
| 136 | txbuf[0] = PCF2123_READ | PCF2123_REG_SC; | ||
| 137 | ret = spi_write_then_read(spi, txbuf, sizeof(txbuf), | ||
| 138 | rxbuf, sizeof(rxbuf)); | ||
| 139 | if (ret < 0) | ||
| 140 | return ret; | ||
| 141 | pcf2123_delay_trec(); | ||
| 142 | |||
| 143 | tm->tm_sec = bcd2bin(rxbuf[0] & 0x7F); | ||
| 144 | tm->tm_min = bcd2bin(rxbuf[1] & 0x7F); | ||
| 145 | tm->tm_hour = bcd2bin(rxbuf[2] & 0x3F); /* rtc hr 0-23 */ | ||
| 146 | tm->tm_mday = bcd2bin(rxbuf[3] & 0x3F); | ||
| 147 | tm->tm_wday = rxbuf[4] & 0x07; | ||
| 148 | tm->tm_mon = bcd2bin(rxbuf[5] & 0x1F) - 1; /* rtc mn 1-12 */ | ||
| 149 | tm->tm_year = bcd2bin(rxbuf[6]); | ||
| 150 | if (tm->tm_year < 70) | ||
| 151 | tm->tm_year += 100; /* assume we are in 1970...2069 */ | ||
| 152 | |||
| 153 | dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " | ||
| 154 | "mday=%d, mon=%d, year=%d, wday=%d\n", | ||
| 155 | __func__, | ||
| 156 | tm->tm_sec, tm->tm_min, tm->tm_hour, | ||
| 157 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | ||
| 158 | |||
| 159 | /* the clock can give out invalid datetime, but we cannot return | ||
| 160 | * -EINVAL otherwise hwclock will refuse to set the time on bootup. | ||
| 161 | */ | ||
| 162 | if (rtc_valid_tm(tm) < 0) | ||
| 163 | dev_err(dev, "retrieved date/time is not valid.\n"); | ||
| 164 | |||
| 165 | return 0; | ||
| 166 | } | ||
| 167 | |||
| 168 | static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm) | ||
| 169 | { | ||
| 170 | struct spi_device *spi = to_spi_device(dev); | ||
| 171 | u8 txbuf[8]; | ||
| 172 | int ret; | ||
| 173 | |||
| 174 | dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " | ||
| 175 | "mday=%d, mon=%d, year=%d, wday=%d\n", | ||
| 176 | __func__, | ||
| 177 | tm->tm_sec, tm->tm_min, tm->tm_hour, | ||
| 178 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); | ||
| 179 | |||
| 180 | /* Stop the counter first */ | ||
| 181 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1; | ||
| 182 | txbuf[1] = 0x20; | ||
| 183 | ret = spi_write(spi, txbuf, 2); | ||
| 184 | if (ret < 0) | ||
| 185 | return ret; | ||
| 186 | pcf2123_delay_trec(); | ||
| 187 | |||
| 188 | /* Set the new time */ | ||
| 189 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_SC; | ||
| 190 | txbuf[1] = bin2bcd(tm->tm_sec & 0x7F); | ||
| 191 | txbuf[2] = bin2bcd(tm->tm_min & 0x7F); | ||
| 192 | txbuf[3] = bin2bcd(tm->tm_hour & 0x3F); | ||
| 193 | txbuf[4] = bin2bcd(tm->tm_mday & 0x3F); | ||
| 194 | txbuf[5] = tm->tm_wday & 0x07; | ||
| 195 | txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */ | ||
| 196 | txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100); | ||
| 197 | |||
| 198 | ret = spi_write(spi, txbuf, sizeof(txbuf)); | ||
| 199 | if (ret < 0) | ||
| 200 | return ret; | ||
| 201 | pcf2123_delay_trec(); | ||
| 202 | |||
| 203 | /* Start the counter */ | ||
| 204 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1; | ||
| 205 | txbuf[1] = 0x00; | ||
| 206 | ret = spi_write(spi, txbuf, 2); | ||
| 207 | if (ret < 0) | ||
| 208 | return ret; | ||
| 209 | pcf2123_delay_trec(); | ||
| 210 | |||
| 211 | return 0; | ||
| 212 | } | ||
| 213 | |||
| 214 | static const struct rtc_class_ops pcf2123_rtc_ops = { | ||
| 215 | .read_time = pcf2123_rtc_read_time, | ||
| 216 | .set_time = pcf2123_rtc_set_time, | ||
| 217 | }; | ||
| 218 | |||
| 219 | static int __devinit pcf2123_probe(struct spi_device *spi) | ||
| 220 | { | ||
| 221 | struct rtc_device *rtc; | ||
| 222 | struct pcf2123_plat_data *pdata; | ||
| 223 | u8 txbuf[2], rxbuf[2]; | ||
| 224 | int ret, i; | ||
| 225 | |||
| 226 | pdata = kzalloc(sizeof(struct pcf2123_plat_data), GFP_KERNEL); | ||
| 227 | if (!pdata) | ||
| 228 | return -ENOMEM; | ||
| 229 | spi->dev.platform_data = pdata; | ||
| 230 | |||
| 231 | /* Send a software reset command */ | ||
| 232 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1; | ||
| 233 | txbuf[1] = 0x58; | ||
| 234 | dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n", | ||
| 235 | txbuf[0], txbuf[1]); | ||
| 236 | ret = spi_write(spi, txbuf, 2 * sizeof(u8)); | ||
| 237 | if (ret < 0) | ||
| 238 | goto kfree_exit; | ||
| 239 | pcf2123_delay_trec(); | ||
| 240 | |||
| 241 | /* Stop the counter */ | ||
| 242 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1; | ||
| 243 | txbuf[1] = 0x20; | ||
| 244 | dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n", | ||
| 245 | txbuf[0], txbuf[1]); | ||
| 246 | ret = spi_write(spi, txbuf, 2 * sizeof(u8)); | ||
| 247 | if (ret < 0) | ||
| 248 | goto kfree_exit; | ||
| 249 | pcf2123_delay_trec(); | ||
| 250 | |||
| 251 | /* See if the counter was actually stopped */ | ||
| 252 | txbuf[0] = PCF2123_READ | PCF2123_REG_CTRL1; | ||
| 253 | dev_dbg(&spi->dev, "checking for presence of RTC (0x%02X)\n", | ||
| 254 | txbuf[0]); | ||
| 255 | ret = spi_write_then_read(spi, txbuf, 1 * sizeof(u8), | ||
| 256 | rxbuf, 2 * sizeof(u8)); | ||
| 257 | dev_dbg(&spi->dev, "received data from RTC (0x%02X 0x%02X)\n", | ||
| 258 | rxbuf[0], rxbuf[1]); | ||
| 259 | if (ret < 0) | ||
| 260 | goto kfree_exit; | ||
| 261 | pcf2123_delay_trec(); | ||
| 262 | |||
| 263 | if (!(rxbuf[0] & 0x20)) { | ||
| 264 | dev_err(&spi->dev, "chip not found\n"); | ||
| 265 | goto kfree_exit; | ||
| 266 | } | ||
| 267 | |||
| 268 | dev_info(&spi->dev, "chip found, driver version " DRV_VERSION "\n"); | ||
| 269 | dev_info(&spi->dev, "spiclk %u KHz.\n", | ||
| 270 | (spi->max_speed_hz + 500) / 1000); | ||
| 271 | |||
| 272 | /* Start the counter */ | ||
| 273 | txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1; | ||
| 274 | txbuf[1] = 0x00; | ||
| 275 | ret = spi_write(spi, txbuf, sizeof(txbuf)); | ||
| 276 | if (ret < 0) | ||
| 277 | goto kfree_exit; | ||
| 278 | pcf2123_delay_trec(); | ||
| 279 | |||
| 280 | /* Finalize the initialization */ | ||
| 281 | rtc = rtc_device_register(pcf2123_driver.driver.name, &spi->dev, | ||
| 282 | &pcf2123_rtc_ops, THIS_MODULE); | ||
| 283 | |||
| 284 | if (IS_ERR(rtc)) { | ||
| 285 | dev_err(&spi->dev, "failed to register.\n"); | ||
| 286 | ret = PTR_ERR(rtc); | ||
| 287 | goto kfree_exit; | ||
| 288 | } | ||
| 289 | |||
| 290 | pdata->rtc = rtc; | ||
| 291 | |||
| 292 | for (i = 0; i < 16; i++) { | ||
| 293 | sprintf(pdata->regs[i].name, "%1x", i); | ||
| 294 | pdata->regs[i].attr.attr.mode = S_IRUGO | S_IWUSR; | ||
| 295 | pdata->regs[i].attr.attr.name = pdata->regs[i].name; | ||
| 296 | pdata->regs[i].attr.show = pcf2123_show; | ||
| 297 | pdata->regs[i].attr.store = pcf2123_store; | ||
| 298 | ret = device_create_file(&spi->dev, &pdata->regs[i].attr); | ||
| 299 | if (ret) { | ||
| 300 | dev_err(&spi->dev, "Unable to create sysfs %s\n", | ||
| 301 | pdata->regs[i].name); | ||
| 302 | goto sysfs_exit; | ||
| 303 | } | ||
| 304 | } | ||
| 305 | |||
| 306 | return 0; | ||
| 307 | |||
| 308 | sysfs_exit: | ||
| 309 | for (i--; i >= 0; i--) | ||
| 310 | device_remove_file(&spi->dev, &pdata->regs[i].attr); | ||
| 311 | |||
| 312 | kfree_exit: | ||
| 313 | kfree(pdata); | ||
| 314 | spi->dev.platform_data = NULL; | ||
| 315 | return ret; | ||
| 316 | } | ||
| 317 | |||
| 318 | static int pcf2123_remove(struct spi_device *spi) | ||
| 319 | { | ||
| 320 | struct pcf2123_plat_data *pdata = spi->dev.platform_data; | ||
| 321 | int i; | ||
| 322 | |||
| 323 | if (pdata) { | ||
| 324 | struct rtc_device *rtc = pdata->rtc; | ||
| 325 | |||
| 326 | if (rtc) | ||
| 327 | rtc_device_unregister(rtc); | ||
| 328 | for (i = 0; i < 16; i++) | ||
| 329 | if (pdata->regs[i].name[0]) | ||
| 330 | device_remove_file(&spi->dev, | ||
| 331 | &pdata->regs[i].attr); | ||
| 332 | kfree(pdata); | ||
| 333 | } | ||
| 334 | |||
| 335 | return 0; | ||
| 336 | } | ||
| 337 | |||
| 338 | static struct spi_driver pcf2123_driver = { | ||
| 339 | .driver = { | ||
| 340 | .name = "rtc-pcf2123", | ||
| 341 | .bus = &spi_bus_type, | ||
| 342 | .owner = THIS_MODULE, | ||
| 343 | }, | ||
| 344 | .probe = pcf2123_probe, | ||
| 345 | .remove = __devexit_p(pcf2123_remove), | ||
| 346 | }; | ||
| 347 | |||
| 348 | static int __init pcf2123_init(void) | ||
| 349 | { | ||
| 350 | return spi_register_driver(&pcf2123_driver); | ||
| 351 | } | ||
| 352 | |||
| 353 | static void __exit pcf2123_exit(void) | ||
| 354 | { | ||
| 355 | spi_unregister_driver(&pcf2123_driver); | ||
| 356 | } | ||
| 357 | |||
| 358 | MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>"); | ||
| 359 | MODULE_DESCRIPTION("NXP PCF2123 RTC driver"); | ||
| 360 | MODULE_LICENSE("GPL"); | ||
| 361 | MODULE_VERSION(DRV_VERSION); | ||
| 362 | |||
| 363 | module_init(pcf2123_init); | ||
| 364 | module_exit(pcf2123_exit); | ||
