rtc: pcf85063: switch to regmap

Switch to regmap to simplify register accesses and remove the need for
pcf85063_stop_clock/pcf85063_start_clock.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index fd13218..9e804ee 100644 (file)
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -439,6 +439,7 @@ config RTC_DRV_PCF8523
 
 config RTC_DRV_PCF85063
        tristate "NXP PCF85063"
+       select REGMAP_I2C
        help
          If you say yes here you get support for the PCF85063 RTC chip
 

diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c
index 550d2e7..37be02a 100644 (file)
--- a/drivers/rtc/rtc-pcf85063.c
+++ b/drivers/rtc/rtc-pcf85063.c
@@ -10,6 +10,8 @@
 #include <linux/bcd.h>
 #include <linux/rtc.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
 
 /*
  * Information for this driver was pulled from the following datasheets.
@@ -28,50 +30,14 @@
 #define PCF85063_REG_SC                        0x04 /* datetime */
 #define PCF85063_REG_SC_OS             0x80
 
-static int pcf85063_stop_clock(struct i2c_client *client, u8 *ctrl1)
-{
-       int rc;
-       u8 reg;
-
-       rc = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);
-       if (rc < 0) {
-               dev_err(&client->dev, "Failing to stop the clock\n");
-               return -EIO;
-       }
-
-       /* stop the clock */
-       reg = rc | PCF85063_REG_CTRL1_STOP;
-
-       rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, reg);
-       if (rc < 0) {
-               dev_err(&client->dev, "Failing to stop the clock\n");
-               return -EIO;
-       }
-
-       *ctrl1 = reg;
-
-       return 0;
-}
-
-static int pcf85063_start_clock(struct i2c_client *client, u8 ctrl1)
-{
-       int rc;
-
-       /* start the clock */
-       ctrl1 &= ~PCF85063_REG_CTRL1_STOP;
-
-       rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, ctrl1);
-       if (rc < 0) {
-               dev_err(&client->dev, "Failing to start the clock\n");
-               return -EIO;
-       }
-
-       return 0;
-}
+struct pcf85063 {
+       struct rtc_device       *rtc;
+       struct regmap           *regmap;
+};
 
 static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
-       struct i2c_client *client = to_i2c_client(dev);
+       struct pcf85063 *pcf85063 = dev_get_drvdata(dev);
        int rc;
        u8 regs[7];
 
@@ -81,16 +47,14 @@ static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm)
         * event, the access must be finished within one second. So, read all
         * time/date registers in one turn.
         */
-       rc = i2c_smbus_read_i2c_block_data(client, PCF85063_REG_SC,
-                                          sizeof(regs), regs);
-       if (rc != sizeof(regs)) {
-               dev_err(&client->dev, "date/time register read error\n");
-               return -EIO;
-       }
+       rc = regmap_bulk_read(pcf85063->regmap, PCF85063_REG_SC, regs,
+                             sizeof(regs));
+       if (rc)
+               return rc;
 
        /* if the clock has lost its power it makes no sense to use its time */
        if (regs[0] & PCF85063_REG_SC_OS) {
-               dev_warn(&client->dev, "Power loss detected, invalid time\n");
+               dev_warn(&pcf85063->rtc->dev, "Power loss detected, invalid time\n");
                return -EINVAL;
        }
 
@@ -108,17 +72,18 @@ static int pcf85063_rtc_read_time(struct device *dev, struct rtc_time *tm)
 
 static int pcf85063_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
-       struct i2c_client *client = to_i2c_client(dev);
+       struct pcf85063 *pcf85063 = dev_get_drvdata(dev);
        int rc;
        u8 regs[7];
-       u8 ctrl1;
 
        /*
         * to accurately set the time, reset the divider chain and keep it in
         * reset state until all time/date registers are written
         */
-       rc = pcf85063_stop_clock(client, &ctrl1);
-       if (rc != 0)
+       rc = regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,
+                               PCF85063_REG_CTRL1_STOP,
+                               PCF85063_REG_CTRL1_STOP);
+       if (rc)
                return rc;
 
        /* hours, minutes and seconds */
@@ -140,23 +105,18 @@ static int pcf85063_rtc_set_time(struct device *dev, struct rtc_time *tm)
        regs[6] = bin2bcd(tm->tm_year - 100);
 
        /* write all registers at once */
-       rc = i2c_smbus_write_i2c_block_data(client, PCF85063_REG_SC,
-                                           sizeof(regs), regs);
-       if (rc < 0) {
-               dev_err(&client->dev, "date/time register write error\n");
+       rc = regmap_bulk_write(pcf85063->regmap, PCF85063_REG_SC,
+                              regs, sizeof(regs));
+       if (rc)
                return rc;
-       }
 
        /*
         * Write the control register as a separate action since the size of
         * the register space is different between the PCF85063TP and
         * PCF85063A devices.  The rollover point can not be used.
         */
-       rc = pcf85063_start_clock(client, ctrl1);
-       if (rc != 0)
-               return rc;
-
-       return 0;
+       return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,
+                                 PCF85063_REG_CTRL1_STOP, 0);
 }
 
 static const struct rtc_class_ops pcf85063_rtc_ops = {
@@ -164,66 +124,74 @@ static const struct rtc_class_ops pcf85063_rtc_ops = {
        .set_time       = pcf85063_rtc_set_time
 };
 
-static int pcf85063_load_capacitance(struct i2c_client *client)
+static int pcf85063_load_capacitance(struct pcf85063 *pcf85063,
+                                    const struct device_node *np)
 {
-       u32 load;
-       int rc;
-       u8 reg;
-
-       rc = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);
-       if (rc < 0)
-               return rc;
-
-       reg = rc;
-       load = 7000;
-       of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",
-                            &load);
+       u32 load = 7000;
+       u8 reg = 0;
 
+       of_property_read_u32(np, "quartz-load-femtofarads", &load);
        switch (load) {
        default:
-               dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 7000",
+               dev_warn(&pcf85063->rtc->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 7000",
                         load);
                /* fall through */
        case 7000:
-               reg &= ~PCF85063_REG_CTRL1_CAP_SEL;
                break;
        case 12500:
-               reg |= PCF85063_REG_CTRL1_CAP_SEL;
+               reg = PCF85063_REG_CTRL1_CAP_SEL;
                break;
        }
 
-       rc = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, reg);
-
-       return rc;
+       return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1,
+                                 PCF85063_REG_CTRL1_CAP_SEL, reg);
 }
 
+static const struct regmap_config regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+       .max_register = 0x11,
+};
+
 static int pcf85063_probe(struct i2c_client *client)
 {
-       struct rtc_device *rtc;
+       struct pcf85063 *pcf85063;
+       unsigned int tmp;
        int err;
 
        dev_dbg(&client->dev, "%s\n", __func__);
 
-       err = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);
-       if (err < 0) {
+       pcf85063 = devm_kzalloc(&client->dev, sizeof(struct pcf85063),
+                               GFP_KERNEL);
+       if (!pcf85063)
+               return -ENOMEM;
+
+       pcf85063->regmap = devm_regmap_init_i2c(client, &regmap_config);
+       if (IS_ERR(pcf85063->regmap))
+               return PTR_ERR(pcf85063->regmap);
+
+       i2c_set_clientdata(client, pcf85063);
+
+       err = regmap_read(pcf85063->regmap, PCF85063_REG_CTRL1, &tmp);
+       if (err) {
                dev_err(&client->dev, "RTC chip is not present\n");
                return err;
        }
 
-       err = pcf85063_load_capacitance(client);
+       pcf85063->rtc = devm_rtc_allocate_device(&client->dev);
+       if (IS_ERR(pcf85063->rtc))
+               return PTR_ERR(pcf85063->rtc);
+
+       err = pcf85063_load_capacitance(pcf85063, client->dev.of_node);
        if (err < 0)
                dev_warn(&client->dev, "failed to set xtal load capacitance: %d",
                         err);
 
-       rtc = devm_rtc_allocate_device(&client->dev);
-       if (IS_ERR(rtc))
-               return PTR_ERR(rtc);
-
-       rtc->ops = &pcf85063_rtc_ops;
-       rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
-       rtc->range_max = RTC_TIMESTAMP_END_2099;
+       pcf85063->rtc->ops = &pcf85063_rtc_ops;
+       pcf85063->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+       pcf85063->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-       return rtc_register_device(rtc);
+       return rtc_register_device(pcf85063->rtc);
 }
 
 #ifdef CONFIG_OF