Input: edt-ft5x06 - get/set M12 report rate by sysfs

Add support for reading/writing scan rate (SC) register for M12 by
sysfs. The register value is equal to the SC (Hz), unlike M06, where
instead it is equal to SC / 10.
Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Tested-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/r/20220621123937.1330389-3-dario.binacchi@amarulasolutions.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/edt-ft5x06.c

@@ -47,6 +47,8 @@
 #define M09_REGISTER_NUM_X		0x94
 #define M09_REGISTER_NUM_Y		0x95
 
+#define M12_REGISTER_REPORT_RATE	0x88
+
 #define EV_REGISTER_THRESHOLD		0x40
 #define EV_REGISTER_GAIN		0x41
 #define EV_REGISTER_OFFSET_Y		0x45
@@ -523,9 +525,9 @@ static EDT_ATTR(offset_y, S_IWUSR | S_IRUGO, NO_REGISTER, NO_REGISTER,
 /* m06: range 20 to 80, m09: range 0 to 30, m12: range 1 to 255... */
 static EDT_ATTR(threshold, S_IWUSR | S_IRUGO, WORK_REGISTER_THRESHOLD,
 		M09_REGISTER_THRESHOLD, EV_REGISTER_THRESHOLD, 0, 255);
-/* m06: range 3 to 14, m12: (0x64: 100Hz) */
+/* m06: range 3 to 14, m12: range 1 to 255 */
 static EDT_ATTR(report_rate, S_IWUSR | S_IRUGO, WORK_REGISTER_REPORT_RATE,
-		NO_REGISTER, NO_REGISTER, 0, 255);
+		M12_REGISTER_REPORT_RATE, NO_REGISTER, 0, 255);
 
 static struct attribute *edt_ft5x06_attrs[] = {
 	&edt_ft5x06_attr_gain.dattr.attr,
@@ -1030,7 +1032,8 @@ static void edt_ft5x06_ts_set_regs(struct edt_ft5x06_ts_data *tsdata)
 	case EDT_M09:
 	case EDT_M12:
 		reg_addr->reg_threshold = M09_REGISTER_THRESHOLD;
-		reg_addr->reg_report_rate = NO_REGISTER;
+		reg_addr->reg_report_rate = tsdata->version == EDT_M12 ?
+			M12_REGISTER_REPORT_RATE : NO_REGISTER;
 		reg_addr->reg_gain = M09_REGISTER_GAIN;
 		reg_addr->reg_offset = M09_REGISTER_OFFSET;
 		reg_addr->reg_offset_x = NO_REGISTER;