rtc: pcf2123: clean up writes to the rtc chip

Add new functions pcf2123_write(), and pcf2123_write_reg().
Use named defines for the values being written.

This improves modularity and readability, and reduces lines of code.

Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

diff --git a/drivers/rtc/rtc-pcf2123.c b/drivers/rtc/rtc-pcf2123.c
index 4c4b3fc5708792931905655bfc85190f3cdce170..0f2ce4546f623da2e5e6c27d22d9a1f3b61c9fd2 100644 (file)
--- a/drivers/rtc/rtc-pcf2123.c
+++ b/drivers/rtc/rtc-pcf2123.c
@@ -140,6 +140,27 @@ static int pcf2123_read(struct device *dev, u8 reg, u8 *rxbuf, size_t size)
        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 ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr,
                            char *buffer)
 {
@@ -163,9 +184,7 @@ static ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr,
 
 static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr,
                             const char *buffer, size_t count) {
-       struct spi_device *spi = to_spi_device(dev);
        struct pcf2123_sysfs_reg *r;
-       u8 txbuf[2];
        unsigned long reg;
        unsigned long val;
 
@@ -181,12 +200,9 @@ static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr,
        if (ret)
                return ret;
 
-       txbuf[0] = PCF2123_WRITE | reg;
-       txbuf[1] = val;
-       ret = spi_write(spi, txbuf, sizeof(txbuf));
+       pcf2123_write_reg(dev, reg, val);
        if (ret < 0)
                return -EIO;
-       pcf2123_delay_trec();
        return count;
 }
 
@@ -220,7 +236,6 @@ 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)
 {
-       struct spi_device *spi = to_spi_device(dev);
        u8 txbuf[8];
        int ret;
 
@@ -231,15 +246,12 @@ 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 */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
-       txbuf[1] = 0x20;
-       ret = spi_write(spi, txbuf, 2);
+       ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_STOP);
        if (ret < 0)
                return ret;
-       pcf2123_delay_trec();
 
        /* Set the new time */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_SC;
+       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);
@@ -248,18 +260,14 @@ static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm)
        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 = spi_write(spi, txbuf, sizeof(txbuf));
+       ret = pcf2123_write(dev, txbuf, sizeof(txbuf));
        if (ret < 0)
                return ret;
-       pcf2123_delay_trec();
 
        /* Start the counter */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
-       txbuf[1] = 0x00;
-       ret = spi_write(spi, txbuf, 2);
+       ret = pcf2123_write_reg(dev, PCF2123_REG_CTRL1, CTRL1_CLEAR);
        if (ret < 0)
                return ret;
-       pcf2123_delay_trec();
 
        return 0;
 }
@@ -273,7 +281,7 @@ static int pcf2123_probe(struct spi_device *spi)
 {
        struct rtc_device *rtc;
        struct pcf2123_plat_data *pdata;
-       u8 txbuf[2], rxbuf[2];
+       u8  rxbuf[2];
        int ret, i;
 
        pdata = devm_kzalloc(&spi->dev, sizeof(struct pcf2123_plat_data),
@@ -283,24 +291,16 @@ static int pcf2123_probe(struct spi_device *spi)
        spi->dev.platform_data = pdata;
 
        /* Send a software reset command */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
-       txbuf[1] = 0x58;
-       dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n",
-                       txbuf[0], txbuf[1]);
-       ret = spi_write(spi, txbuf, 2 * sizeof(u8));
+       dev_dbg(&spi->dev, "resetting RTC\n");
+       ret = pcf2123_write_reg(&spi->dev, PCF2123_REG_CTRL1, CTRL1_SW_RESET);
        if (ret < 0)
                goto kfree_exit;
-       pcf2123_delay_trec();
 
        /* Stop the counter */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
-       txbuf[1] = 0x20;
-       dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n",
-                       txbuf[0], txbuf[1]);
-       ret = spi_write(spi, txbuf, 2 * sizeof(u8));
+       dev_dbg(&spi->dev, "stopping RTC\n");
+       ret = pcf2123_write_reg(&spi->dev, PCF2123_REG_CTRL1, CTRL1_STOP);
        if (ret < 0)
                goto kfree_exit;
-       pcf2123_delay_trec();
 
        /* See if the counter was actually stopped */
        dev_dbg(&spi->dev, "checking for presence of RTC\n");
@@ -321,12 +321,9 @@ static int pcf2123_probe(struct spi_device *spi)
                        (spi->max_speed_hz + 500) / 1000);
 
        /* Start the counter */
-       txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
-       txbuf[1] = 0x00;
-       ret = spi_write(spi, txbuf, sizeof(txbuf));
+       ret = pcf2123_write_reg(&spi->dev, PCF2123_REG_CTRL1, CTRL1_CLEAR);
        if (ret < 0)
                goto kfree_exit;
-       pcf2123_delay_trec();
 
        /* Finalize the initialization */
        rtc = devm_rtc_device_register(&spi->dev, pcf2123_driver.driver.name,