diff options
Diffstat (limited to 'drivers/rtc/rtc-pcf2127.c')
| -rw-r--r-- | drivers/rtc/rtc-pcf2127.c | 59 |
1 files changed, 33 insertions, 26 deletions
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 58eb96506e4b..cd8def79b379 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -19,26 +19,32 @@ #include <linux/of.h> #include <linux/regmap.h> -#define PCF2127_REG_CTRL1 (0x00) /* Control Register 1 */ -#define PCF2127_REG_CTRL2 (0x01) /* Control Register 2 */ - -#define PCF2127_REG_CTRL3 (0x02) /* Control Register 3 */ -#define PCF2127_REG_CTRL3_BLF BIT(2) - -#define PCF2127_REG_SC (0x03) /* datetime */ -#define PCF2127_REG_MN (0x04) -#define PCF2127_REG_HR (0x05) -#define PCF2127_REG_DM (0x06) -#define PCF2127_REG_DW (0x07) -#define PCF2127_REG_MO (0x08) -#define PCF2127_REG_YR (0x09) - -/* the pcf2127 has 512 bytes nvmem, pcf2129 doesn't */ -#define PCF2127_REG_RAM_addr_MSB 0x1a -#define PCF2127_REG_RAM_wrt_cmd 0x1c -#define PCF2127_REG_RAM_rd_cmd 0x1d +/* Control register 1 */ +#define PCF2127_REG_CTRL1 0x00 +/* Control register 2 */ +#define PCF2127_REG_CTRL2 0x01 +/* Control register 3 */ +#define PCF2127_REG_CTRL3 0x02 +#define PCF2127_BIT_CTRL3_BLF BIT(2) +/* Time and date registers */ +#define PCF2127_REG_SC 0x03 +#define PCF2127_BIT_SC_OSF BIT(7) +#define PCF2127_REG_MN 0x04 +#define PCF2127_REG_HR 0x05 +#define PCF2127_REG_DM 0x06 +#define PCF2127_REG_DW 0x07 +#define PCF2127_REG_MO 0x08 +#define PCF2127_REG_YR 0x09 +/* + * RAM registers + * PCF2127 has 512 bytes general-purpose static RAM (SRAM) that is + * battery backed and can survive a power outage. + * PCF2129 doesn't have this feature. + */ +#define PCF2127_REG_RAM_ADDR_MSB 0x1A +#define PCF2127_REG_RAM_WRT_CMD 0x1C +#define PCF2127_REG_RAM_RD_CMD 0x1D -#define PCF2127_OSF BIT(7) /* Oscillator Fail flag */ struct pcf2127 { struct rtc_device *rtc; @@ -73,11 +79,12 @@ static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm) return ret; } - if (buf[PCF2127_REG_CTRL3] & PCF2127_REG_CTRL3_BLF) + if (buf[PCF2127_REG_CTRL3] & PCF2127_BIT_CTRL3_BLF) dev_info(dev, "low voltage detected, check/replace RTC battery.\n"); - if (buf[PCF2127_REG_SC] & PCF2127_OSF) { + /* Clock integrity is not guaranteed when OSF flag is set. */ + if (buf[PCF2127_REG_SC] & PCF2127_BIT_SC_OSF) { /* * no need clear the flag here, * it will be cleared once the new date is saved @@ -166,7 +173,7 @@ static int pcf2127_rtc_ioctl(struct device *dev, if (ret) return ret; - touser = touser & PCF2127_REG_CTRL3_BLF ? 1 : 0; + touser = touser & PCF2127_BIT_CTRL3_BLF ? 1 : 0; if (copy_to_user((void __user *)arg, &touser, sizeof(int))) return -EFAULT; @@ -192,12 +199,12 @@ static int pcf2127_nvmem_read(void *priv, unsigned int offset, int ret; unsigned char offsetbuf[] = { offset >> 8, offset }; - ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_addr_MSB, + ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_ADDR_MSB, offsetbuf, 2); if (ret) return ret; - ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_RAM_rd_cmd, + ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_RAM_RD_CMD, val, bytes); return ret ?: bytes; @@ -210,12 +217,12 @@ static int pcf2127_nvmem_write(void *priv, unsigned int offset, int ret; unsigned char offsetbuf[] = { offset >> 8, offset }; - ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_addr_MSB, + ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_ADDR_MSB, offsetbuf, 2); if (ret) return ret; - ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_wrt_cmd, + ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_WRT_CMD, val, bytes); return ret ?: bytes; |