rtc: ds1347: use regmap_update_bits

Use regmap_update_bits instead of open coding. Also add proper error
handling.

Link: https://lore.kernel.org/r/20191007134724.15505-9-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-ds1347.c b/drivers/rtc/rtc-ds1347.c
index eeaf435..a49ce99 100644 (file)
--- a/drivers/rtc/rtc-ds1347.c
+++ b/drivers/rtc/rtc-ds1347.c
@@ -29,6 +29,8 @@
 #define DS1347_STATUS_REG      0x17
 #define DS1347_CLOCK_BURST     0x3F
 
+#define DS1347_WP_BIT          BIT(7)
+
 #define DS1347_NEOSC_BIT       BIT(7)
 #define DS1347_OSF_BIT         BIT(2)
 
@@ -117,7 +119,7 @@ static int ds1347_probe(struct spi_device *spi)
        struct rtc_device *rtc;
        struct regmap_config config;
        struct regmap *map;
-       unsigned int data;
+       int err;
 
        memset(&config, 0, sizeof(config));
        config.reg_bits = 8;
@@ -141,9 +143,9 @@ static int ds1347_probe(struct spi_device *spi)
        spi_set_drvdata(spi, map);
 
        /* Disable the write protect of rtc */
-       regmap_read(map, DS1347_CONTROL_REG, &data);
-       data = data & ~(1<<7);
-       regmap_write(map, DS1347_CONTROL_REG, data);
+       err = regmap_update_bits(map, DS1347_CONTROL_REG, DS1347_WP_BIT, 0);
+       if (err)
+               return err;
 
        rtc = devm_rtc_allocate_device(&spi->dev);
        if (IS_ERR(rtc))