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author | Dylan Howey <Dylan.Howey@tennantco.com> | 2019-05-03 19:52:10 +0000 |
---|---|---|
committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-06-19 16:20:22 +0200 |
commit | 790d033933b8a1d6bd537bdd6c08d9af745d9b78 (patch) | |
tree | bbafe0675abef89a2cb6e952c33ea51b38f45994 /drivers/rtc | |
parent | 2372a7d32b694e39bfac54d7f4dd7c0edb02d19e (diff) | |
download | linux-790d033933b8a1d6bd537bdd6c08d9af745d9b78.tar.gz linux-790d033933b8a1d6bd537bdd6c08d9af745d9b78.tar.bz2 linux-790d033933b8a1d6bd537bdd6c08d9af745d9b78.zip |
rtc: pcf2123: port to regmap
Also remove pcf2123_delay_trec. This claimed to add a 30ns delay to SPI
writes, but I could not see any reference to this requirement in the
datasheet. Closest thing I could find to a requirement are timings for the
SPI chip enable line, which cannot be controlled by this driver (the ndelay
came after the call to spi_write_then_read, which means it would sleep
after CE has already gone inactive). Things seem to work fine without it.
Signed-off-by: Dylan Howey <Dylan.Howey@tennantco.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc')
-rw-r--r-- | drivers/rtc/rtc-pcf2123.c | 142 |
1 files changed, 61 insertions, 81 deletions
diff --git a/drivers/rtc/rtc-pcf2123.c b/drivers/rtc/rtc-pcf2123.c index fb5cb81f2161..32bfed7eefd4 100644 --- a/drivers/rtc/rtc-pcf2123.c +++ b/drivers/rtc/rtc-pcf2123.c @@ -44,6 +44,7 @@ #include <linux/rtc.h> #include <linux/spi/spi.h> #include <linux/module.h> +#include <linux/regmap.h> /* REGISTERS */ #define PCF2123_REG_CTRL1 (0x00) /* Control Register 1 */ @@ -98,6 +99,7 @@ #define OFFSET_SIGN_BIT 6 /* 2's complement sign bit */ #define OFFSET_COARSE BIT(7) /* Coarse mode offset */ #define OFFSET_STEP (2170) /* Offset step in parts per billion */ +#define OFFSET_MASK GENMASK(6, 0) /* Offset value */ /* READ/WRITE ADDRESS BITS */ #define PCF2123_WRITE BIT(4) @@ -108,66 +110,33 @@ static struct spi_driver pcf2123_driver; struct pcf2123_plat_data { struct rtc_device *rtc; + struct regmap *map; }; -/* - * Causes a 30 nanosecond delay to ensure that the PCF2123 chip select - * is released properly after an SPI write. This function should be - * called after EVERY read/write call over SPI. - */ -static inline void pcf2123_delay_trec(void) -{ - ndelay(30); -} - -static int pcf2123_read(struct device *dev, u8 reg, u8 *rxbuf, size_t size) -{ - struct spi_device *spi = to_spi_device(dev); - int ret; - - reg |= PCF2123_READ; - ret = spi_write_then_read(spi, ®, 1, rxbuf, size); - pcf2123_delay_trec(); - - return ret; -} - -static int pcf2123_write(struct device *dev, u8 *txbuf, size_t size) -{ - struct spi_device *spi = to_spi_device(dev); - int ret; - - txbuf[0] |= PCF2123_WRITE; - ret = spi_write(spi, txbuf, size); - pcf2123_delay_trec(); - - return ret; -} - -static int pcf2123_write_reg(struct device *dev, u8 reg, u8 val) -{ - u8 txbuf[2]; - - txbuf[0] = reg; - txbuf[1] = val; - return pcf2123_write(dev, txbuf, sizeof(txbuf)); -} +static const struct regmap_config pcf2123_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .read_flag_mask = PCF2123_READ, + .write_flag_mask = PCF2123_WRITE, + .max_register = PCF2123_REG_CTDWN_TMR, +}; static int pcf2123_read_offset(struct device *dev, long *offset) { - int ret; - s8 reg; + struct pcf2123_plat_data *pdata = dev_get_platdata(dev); + int ret, val; + unsigned int reg; - ret = pcf2123_read(dev, PCF2123_REG_OFFSET, ®, 1); - if (ret < 0) + ret = regmap_read(pdata->map, PCF2123_REG_OFFSET, ®); + if (ret) return ret; + val = sign_extend32((reg & OFFSET_MASK), OFFSET_SIGN_BIT); + if (reg & OFFSET_COARSE) - reg <<= 1; /* multiply by 2 and sign extend */ - else - reg = sign_extend32(reg, OFFSET_SIGN_BIT); + val *= 2; - *offset = ((long)reg) * OFFSET_STEP; + *offset = ((long)val) * OFFSET_STEP; return 0; } @@ -184,6 +153,7 @@ static int pcf2123_read_offset(struct device *dev, long *offset) */ static int pcf2123_set_offset(struct device *dev, long offset) { + struct pcf2123_plat_data *pdata = dev_get_platdata(dev); s8 reg; if (offset > OFFSET_STEP * 127) @@ -203,16 +173,18 @@ static int pcf2123_set_offset(struct device *dev, long offset) reg |= OFFSET_COARSE; } - return pcf2123_write_reg(dev, PCF2123_REG_OFFSET, reg); + return regmap_write(pdata->map, PCF2123_REG_OFFSET, (unsigned int)reg); } static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm) { + struct pcf2123_plat_data *pdata = dev_get_platdata(dev); u8 rxbuf[7]; int ret; - ret = pcf2123_read(dev, PCF2123_REG_SC, rxbuf, sizeof(rxbuf)); - if (ret < 0) + ret = regmap_bulk_read(pdata->map, PCF2123_REG_SC, rxbuf, + sizeof(rxbuf)); + if (ret) return ret; if (rxbuf[0] & OSC_HAS_STOPPED) { @@ -241,7 +213,8 @@ static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm) static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm) { - u8 txbuf[8]; + struct pcf2123_plat_data *pdata = dev_get_platdata(dev); + u8 txbuf[7]; int ret; dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " @@ -251,27 +224,27 @@ static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm) tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); /* Stop the counter first */ - ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_STOP); - if (ret < 0) + ret = regmap_write(pdata->map, PCF2123_REG_CTRL1, CTRL1_STOP); + if (ret) return ret; /* Set the new time */ - txbuf[0] = PCF2123_REG_SC; - txbuf[1] = bin2bcd(tm->tm_sec & 0x7F); - txbuf[2] = bin2bcd(tm->tm_min & 0x7F); - txbuf[3] = bin2bcd(tm->tm_hour & 0x3F); - txbuf[4] = bin2bcd(tm->tm_mday & 0x3F); - txbuf[5] = tm->tm_wday & 0x07; - txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */ - txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100); - - ret = pcf2123_write(dev, txbuf, sizeof(txbuf)); - if (ret < 0) + txbuf[0] = bin2bcd(tm->tm_sec & 0x7F); + txbuf[1] = bin2bcd(tm->tm_min & 0x7F); + txbuf[2] = bin2bcd(tm->tm_hour & 0x3F); + txbuf[3] = bin2bcd(tm->tm_mday & 0x3F); + txbuf[4] = tm->tm_wday & 0x07; + txbuf[5] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */ + txbuf[6] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100); + + ret = regmap_bulk_write(pdata->map, PCF2123_REG_SC, txbuf, + sizeof(txbuf)); + if (ret) return ret; /* Start the counter */ - ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_CLEAR); - if (ret < 0) + ret = regmap_write(pdata->map, PCF2123_REG_CTRL1, CTRL1_CLEAR); + if (ret) return ret; return 0; @@ -279,33 +252,33 @@ static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm) static int pcf2123_reset(struct device *dev) { + struct pcf2123_plat_data *pdata = dev_get_platdata(dev); int ret; - u8 rxbuf[2]; + unsigned int val = 0; - ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_SW_RESET); - if (ret < 0) + ret = regmap_write(pdata->map, PCF2123_REG_CTRL1, CTRL1_SW_RESET); + if (ret) return ret; /* Stop the counter */ dev_dbg(dev, "stopping RTC\n"); - ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_STOP); - if (ret < 0) + ret = regmap_write(pdata->map, PCF2123_REG_CTRL1, CTRL1_STOP); + if (ret) return ret; /* See if the counter was actually stopped */ dev_dbg(dev, "checking for presence of RTC\n"); - ret = pcf2123_read(dev, PCF2123_REG_CTRL1, rxbuf, sizeof(rxbuf)); - if (ret < 0) + ret = regmap_read(pdata->map, PCF2123_REG_CTRL1, &val); + if (ret) return ret; - dev_dbg(dev, "received data from RTC (0x%02X 0x%02X)\n", - rxbuf[0], rxbuf[1]); - if (!(rxbuf[0] & CTRL1_STOP)) + dev_dbg(dev, "received data from RTC (0x%08X)\n", val); + if (!(val & CTRL1_STOP)) return -ENODEV; /* Start the counter */ - ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_CLEAR); - if (ret < 0) + ret = regmap_write(pdata->map, PCF2123_REG_CTRL1, CTRL1_CLEAR); + if (ret) return ret; return 0; @@ -332,6 +305,13 @@ static int pcf2123_probe(struct spi_device *spi) return -ENOMEM; spi->dev.platform_data = pdata; + pdata->map = devm_regmap_init_spi(spi, &pcf2123_regmap_config); + + if (IS_ERR(pdata->map)) { + dev_err(&spi->dev, "regmap init failed.\n"); + goto kfree_exit; + } + ret = pcf2123_rtc_read_time(&spi->dev, &tm); if (ret < 0) { ret = pcf2123_reset(&spi->dev); |