[PATCH 1/6] input: elants: document some registers and values

[Michał Mirosław <mirq-linux@xxxxxxxxxxxx>]

Add information found in downstream kernels, to make the code less
magic.

Signed-off-by: Michał Mirosław <mirq-linux@xxxxxxxxxxxx>
---
 drivers/input/touchscreen/elants_i2c.c | 29 +++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c
index d4ad24ea54c8..887888c53996 100644
--- a/drivers/input/touchscreen/elants_i2c.c
+++ b/drivers/input/touchscreen/elants_i2c.c
@@ -77,7 +77,11 @@
 
 #define HEADER_REPORT_10_FINGER	0x62
 
-/* Header (4 bytes) plus 3 fill 10-finger packets */
+/* Power state */
+#define PWR_STATE_DEEP_SLEEP	0
+#define PWR_STATE_NORMAL	1
+
+/* Header (4 bytes) plus 3 full 10-finger packets */
 #define MAX_PACKET_SIZE		169
 
 #define BOOT_TIME_DELAY_MS	50
@@ -87,10 +91,21 @@
 #define E_ELAN_INFO_BC_VER	0x10
 #define E_ELAN_INFO_TEST_VER	0xE0
 #define E_ELAN_INFO_FW_ID	0xF0
+#define E_POWER_MODE		0x40
+#define E_POWER_STATE		0x50
+#define E_INFO_X_RES		0x60
+#define E_INFO_Y_RES		0x63
 #define E_INFO_OSR		0xD6
 #define E_INFO_PHY_SCAN		0xD7
 #define E_INFO_PHY_DRIVER	0xD8
 
+/* FW write command, 0x54 0x?? 0x0, 0x01 */
+#define E_POWER_MODE_BATTERY	0x40
+#define E_POWER_MODE_AC		0x41
+#define E_POWER_MODE_USB	0x42
+#define E_POWER_STATE_SLEEP	0x50
+#define E_POWER_STATE_RESUME	0x58
+
 #define MAX_RETRIES		3
 #define MAX_FW_UPDATE_RETRIES	30
 
@@ -231,8 +246,8 @@ static int elants_i2c_calibrate(struct elants_data *ts)
 {
 	struct i2c_client *client = ts->client;
 	int ret, error;
-	static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
-	static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
+	static const u8 w_flashkey[] = { CMD_HEADER_WRITE, 0xC0, 0xE1, 0x5A };
+	static const u8 rek[] = { CMD_HEADER_WRITE, 0x29, 0x00, 0x01 };
 	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
 
 	disable_irq(client->irq);
@@ -1295,7 +1310,9 @@ static int __maybe_unused elants_i2c_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	struct elants_data *ts = i2c_get_clientdata(client);
-	const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
+	const u8 set_sleep_cmd[] = {
+		CMD_HEADER_WRITE, E_POWER_STATE_SLEEP, 0x00, 0x01
+	};
 	int retry_cnt;
 	int error;
 
@@ -1332,7 +1349,9 @@ static int __maybe_unused elants_i2c_resume(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	struct elants_data *ts = i2c_get_clientdata(client);
-	const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
+	const u8 set_active_cmd[] = {
+		CMD_HEADER_WRITE, E_POWER_STATE_RESUME, 0x00, 0x01
+	};
 	int retry_cnt;
 	int error;
 
-- 
2.20.1