Input: imagis - use FIELD_GET where applicable

Instead of manually extracting certain bits from registers with binary
ANDs and shifts, the FIELD_GET macro can be used. With this in mind, the
*_SHIFT macros can be dropped.

Signed-off-by: Duje Mihanović <duje.mihanovic@skole.hr>
Link: https://lore.kernel.org/r/20240306-b4-imagis-keys-v3-1-2c429afa8420@skole.hr
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: LegoLivesMatter

drivers/input/touchscreen/imagis.c

@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
+#include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
@@ -29,12 +30,9 @@
 #define IST3038C_I2C_RETRY_COUNT	3
 #define IST3038C_MAX_FINGER_NUM		10
 #define IST3038C_X_MASK			GENMASK(23, 12)
-#define IST3038C_X_SHIFT		12
 #define IST3038C_Y_MASK			GENMASK(11, 0)
 #define IST3038C_AREA_MASK		GENMASK(27, 24)
-#define IST3038C_AREA_SHIFT		24
 #define IST3038C_FINGER_COUNT_MASK	GENMASK(15, 12)
-#define IST3038C_FINGER_COUNT_SHIFT	12
 #define IST3038C_FINGER_STATUS_MASK	GENMASK(9, 0)
 
 struct imagis_properties {
@@ -106,16 +104,15 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
 		goto out;
 	}
 
-	finger_count = (intr_message & IST3038C_FINGER_COUNT_MASK) >>
-				IST3038C_FINGER_COUNT_SHIFT;
+	finger_count = FIELD_GET(IST3038C_FINGER_COUNT_MASK, intr_message);
 	if (finger_count > IST3038C_MAX_FINGER_NUM) {
 		dev_err(&ts->client->dev,
 			"finger count %d is more than maximum supported\n",
 			finger_count);
 		goto out;
 	}
 
-	finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK;
+	finger_pressed = FIELD_GET(IST3038C_FINGER_STATUS_MASK, intr_message);
 
 	for (i = 0; i < finger_count; i++) {
 		if (ts->tdata->protocol_b)
@@ -136,12 +133,11 @@ static irqreturn_t imagis_interrupt(int irq, void *dev_id)
 		input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER,
 					   finger_pressed & BIT(i));
 		touchscreen_report_pos(ts->input_dev, &ts->prop,
-				       (finger_status & IST3038C_X_MASK) >>
-						IST3038C_X_SHIFT,
-				       finger_status & IST3038C_Y_MASK, 1);
+				       FIELD_GET(IST3038C_X_MASK, finger_status),
+				       FIELD_GET(IST3038C_Y_MASK, finger_status),
+				       true);
 		input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR,
-				 (finger_status & IST3038C_AREA_MASK) >>
-					IST3038C_AREA_SHIFT);
+				 FIELD_GET(IST3038C_AREA_MASK, finger_status));
 	}
 
 	input_mt_sync_frame(ts->input_dev);