hwmon: (adt7x10) Convert to use regmap

Using regmap lets us use the regmap subsystem for SPI vs. I2C register
accesses. It lets us hide access differences in backend code and lets
the common code just access registers without knowing their size.
We can also use regmap for register caching.

Tested-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Reviewed-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 71 insertions, 17 deletions

diff --git a/drivers/hwmon/adt7310.c b/drivers/hwmon/adt7310.c
index c40cac16af68..a83092470bce 100644
--- a/drivers/hwmon/adt7310.c
+++ b/drivers/hwmon/adt7310.c
@@ -8,6 +8,7 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/regmap.h>
 #include <linux/spi/spi.h>
 #include <asm/unaligned.h>
 
@@ -38,16 +39,13 @@ static const u8 adt7310_reg_table[] = {
 
 #define AD7310_COMMAND(reg) (adt7310_reg_table[(reg)] << ADT7310_CMD_REG_OFFSET)
 
-static int adt7310_spi_read_word(struct device *dev, u8 reg)
+static int adt7310_spi_read_word(struct spi_device *spi, u8 reg)
 {
-	struct spi_device *spi = to_spi_device(dev);
-
 	return spi_w8r16be(spi, AD7310_COMMAND(reg) | ADT7310_CMD_READ);
 }
 
-static int adt7310_spi_write_word(struct device *dev, u8 reg, u16 data)
+static int adt7310_spi_write_word(struct spi_device *spi, u8 reg, u16 data)
 {
-	struct spi_device *spi = to_spi_device(dev);
 	u8 buf[3];
 
 	buf[0] = AD7310_COMMAND(reg);
@@ -56,17 +54,13 @@ static int adt7310_spi_write_word(struct device *dev, u8 reg, u16 data)
 	return spi_write(spi, buf, sizeof(buf));
 }
 
-static int adt7310_spi_read_byte(struct device *dev, u8 reg)
+static int adt7310_spi_read_byte(struct spi_device *spi, u8 reg)
 {
-	struct spi_device *spi = to_spi_device(dev);
-
 	return spi_w8r8(spi, AD7310_COMMAND(reg) | ADT7310_CMD_READ);
 }
 
-static int adt7310_spi_write_byte(struct device *dev, u8 reg,
-	u8 data)
+static int adt7310_spi_write_byte(struct spi_device *spi, u8 reg, u8 data)
 {
-	struct spi_device *spi = to_spi_device(dev);
 	u8 buf[2];
 
 	buf[0] = AD7310_COMMAND(reg);
@@ -75,17 +69,77 @@ static int adt7310_spi_write_byte(struct device *dev, u8 reg,
 	return spi_write(spi, buf, sizeof(buf));
 }
 
-static const struct adt7x10_ops adt7310_spi_ops = {
-	.read_word = adt7310_spi_read_word,
-	.write_word = adt7310_spi_write_word,
-	.read_byte = adt7310_spi_read_byte,
-	.write_byte = adt7310_spi_write_byte,
+static bool adt7310_regmap_is_volatile(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case ADT7X10_TEMPERATURE:
+	case ADT7X10_STATUS:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static int adt7310_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	struct spi_device *spi = context;
+	int regval;
+
+	switch (reg) {
+	case ADT7X10_TEMPERATURE:
+	case ADT7X10_T_ALARM_HIGH:
+	case ADT7X10_T_ALARM_LOW:
+	case ADT7X10_T_CRIT:
+		regval = adt7310_spi_read_word(spi, reg);
+		break;
+	default:
+		regval = adt7310_spi_read_byte(spi, reg);
+		break;
+	}
+	if (regval < 0)
+		return regval;
+	*val = regval;
+	return 0;
+}
+
+static int adt7310_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	struct spi_device *spi = context;
+	int ret;
+
+	switch (reg) {
+	case ADT7X10_TEMPERATURE:
+	case ADT7X10_T_ALARM_HIGH:
+	case ADT7X10_T_ALARM_LOW:
+	case ADT7X10_T_CRIT:
+		ret = adt7310_spi_write_word(spi, reg, val);
+		break;
+	default:
+		ret = adt7310_spi_write_byte(spi, reg, val);
+		break;
+	}
+	return ret;
+}
+
+static const struct regmap_config adt7310_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_reg = adt7310_regmap_is_volatile,
+	.reg_read = adt7310_reg_read,
+	.reg_write = adt7310_reg_write,
 };
 
 static int adt7310_spi_probe(struct spi_device *spi)
 {
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init(&spi->dev, NULL, spi, &adt7310_regmap_config);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
 	return adt7x10_probe(&spi->dev, spi_get_device_id(spi)->name, spi->irq,
-			&adt7310_spi_ops);
+			     regmap);
 }
 
 static int adt7310_spi_remove(struct spi_device *spi)