[PATCH] iio: adc: mcp3422: write bit operations with bitfield macros

[Marcelo Machado Lage]

Replace manual bit manipulations with GENMASK(), FIELD_GET(),
FIELD_PREP() and FIELD_MODIFY() calls. The resulting code is more
readable and maintainable, and some macros previously defined in the
header are not needed anymore.

Signed-off-by: Marcelo Machado Lage <marcelomlage em usp.br>
Co-developed-by: Vinicius Lira <vinilira em usp.br>
Signed-off-by: Vinicius Lira <vinilira em usp.br>
---
 drivers/iio/adc/mcp3422.c | 42 ++++++++++++++++-----------------------
 1 file changed, 17 insertions(+), 25 deletions(-)

diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c
index 50834fdcf738..cfb3968c248e 100644
--- a/drivers/iio/adc/mcp3422.c
+++ b/drivers/iio/adc/mcp3422.c
@@ -25,9 +25,9 @@
 #include <linux/iio/sysfs.h>
 
 /* Masks */
-#define MCP3422_CHANNEL_MASK	0x60
-#define MCP3422_PGA_MASK	0x03
-#define MCP3422_SRATE_MASK	0x0C
+#define MCP3422_CHANNEL_MASK	GENMASK(6, 5)
+#define MCP3422_PGA_MASK	GENMASK(1, 0)
+#define MCP3422_SRATE_MASK	GENMASK(3, 2)
 #define MCP3422_SRATE_240	0x0
 #define MCP3422_SRATE_60	0x1
 #define MCP3422_SRATE_15	0x2
@@ -38,13 +38,9 @@
 #define MCP3422_PGA_8	3
 #define MCP3422_CONT_SAMPLING	0x10
 
-#define MCP3422_CHANNEL(config)	(((config) & MCP3422_CHANNEL_MASK) >> 5)
-#define MCP3422_PGA(config)	((config) & MCP3422_PGA_MASK)
-#define MCP3422_SAMPLE_RATE(config)	(((config) & MCP3422_SRATE_MASK) >> 2)
-
-#define MCP3422_CHANNEL_VALUE(value) (((value) << 5) & MCP3422_CHANNEL_MASK)
-#define MCP3422_PGA_VALUE(value) ((value) & MCP3422_PGA_MASK)
-#define MCP3422_SAMPLE_RATE_VALUE(value) ((value << 2) & MCP3422_SRATE_MASK)
+#define MCP3422_CHANNEL(config)		FIELD_GET(MCP3422_CHANNEL_MASK, config)
+#define MCP3422_PGA(config)			FIELD_GET(MCP3422_PGA_MASK, config)
+#define MCP3422_SAMPLE_RATE(config)	FIELD_GET(MCP3422_SRATE_MASK, config)
 
 #define MCP3422_CHAN(_index) \
 	{ \
@@ -138,10 +134,10 @@ static int mcp3422_read_channel(struct mcp3422 *adc,
 
 	if (req_channel != MCP3422_CHANNEL(adc->config)) {
 		config = adc->config;
-		config &= ~MCP3422_CHANNEL_MASK;
-		config |= MCP3422_CHANNEL_VALUE(req_channel);
-		config &= ~MCP3422_PGA_MASK;
-		config |= MCP3422_PGA_VALUE(adc->pga[req_channel]);
+
+		FIELD_MODIFY(MCP3422_CHANNEL_MASK, &config, req_channel);
+		FIELD_MODIFY(MCP3422_PGA_MASK, &config, adc->pga[req_channel]);
+
 		ret = mcp3422_update_config(adc, config);
 		if (ret < 0) {
 			mutex_unlock(&adc->lock);
@@ -211,10 +207,8 @@ static int mcp3422_write_raw(struct iio_dev *iio,
 			if (val2 == mcp3422_scales[sample_rate][i]) {
 				adc->pga[req_channel] = i;
 
-				config &= ~MCP3422_CHANNEL_MASK;
-				config |= MCP3422_CHANNEL_VALUE(req_channel);
-				config &= ~MCP3422_PGA_MASK;
-				config |= MCP3422_PGA_VALUE(adc->pga[req_channel]);
+				FIELD_MODIFY(MCP3422_CHANNEL_MASK, &config, req_channel);
+				FIELD_MODIFY(MCP3422_PGA_MASK, &config, adc->pga[req_channel]);
 
 				return mcp3422_update_config(adc, config);
 			}
@@ -241,10 +235,8 @@ static int mcp3422_write_raw(struct iio_dev *iio,
 			return -EINVAL;
 		}
 
-		config &= ~MCP3422_CHANNEL_MASK;
-		config |= MCP3422_CHANNEL_VALUE(req_channel);
-		config &= ~MCP3422_SRATE_MASK;
-		config |= MCP3422_SAMPLE_RATE_VALUE(temp);
+		FIELD_MODIFY(MCP3422_CHANNEL_MASK, &config, req_channel);
+		FIELD_MODIFY(MCP3422_SRATE_MASK, &config, temp);
 
 		return mcp3422_update_config(adc, config);
 
@@ -377,9 +369,9 @@ static int mcp3422_probe(struct i2c_client *client)
 
 	/* meaningful default configuration */
 	config = (MCP3422_CONT_SAMPLING
-		| MCP3422_CHANNEL_VALUE(0)
-		| MCP3422_PGA_VALUE(MCP3422_PGA_1)
-		| MCP3422_SAMPLE_RATE_VALUE(MCP3422_SRATE_240));
+		| FIELD_PREP(MCP3422_CHANNEL_MASK, 0)
+		| FIELD_PREP(MCP3422_PGA_MASK, MCP3422_PGA_1)
+		| FIELD_PREP(MCP3422_SRATE_MASK, MCP3422_SRATE_240));
 	err = mcp3422_update_config(adc, config);
 	if (err < 0)
 		return err;
-- 
2.34.1