[PATCH] HID: hid-goodix: Improve handling of HID feature reports

[Charles Wang <charles.goodix@xxxxxxxxx>]

1) Align with the i2c-hid driver by returning 0 instead of -EINVAL when
an empty response is received, ensuring that userspace programs utilizing
the hidraw node receive consistent return values.

2) Implement the hid get/set feature report function using a separate
address, rather than sharing an address with coordinate reporting, to
prevent feature events from being overwritten by coordinate events.

Signed-off-by: Charles Wang <charles.goodix@xxxxxxxxx>
---
 drivers/hid/hid-goodix-spi.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/hid/hid-goodix-spi.c b/drivers/hid/hid-goodix-spi.c
index 0f87bf9c6..6ae2300a6 100644
--- a/drivers/hid/hid-goodix-spi.c
+++ b/drivers/hid/hid-goodix-spi.c
@@ -19,6 +19,7 @@
 #define GOODIX_HID_DESC_ADDR		0x1058C
 #define GOODIX_HID_REPORT_DESC_ADDR	0x105AA
 #define GOODIX_HID_SIGN_ADDR		0x10D32
+#define GOODIX_HID_CMD_ADDR		0x10364
 
 #define GOODIX_HID_GET_REPORT_CMD	0x02
 #define GOODIX_HID_SET_REPORT_CMD	0x03
@@ -348,7 +349,7 @@ static int goodix_hid_check_ack_status(struct goodix_ts_data *ts, u32 *resp_len)
 		 * - byte 0:    Ack flag, value of 1 for data ready
 		 * - bytes 1-2: Response data length
 		 */
-		error = goodix_spi_read(ts, ts->hid_report_addr,
+		error = goodix_spi_read(ts, GOODIX_HID_CMD_ADDR,
 					&hdr, sizeof(hdr));
 		if (!error && (hdr.flag & GOODIX_HID_ACK_READY_FLAG)) {
 			len = le16_to_cpu(hdr.size);
@@ -356,7 +357,7 @@ static int goodix_hid_check_ack_status(struct goodix_ts_data *ts, u32 *resp_len)
 				dev_err(ts->dev, "hrd.size too short: %d", len);
 				return -EINVAL;
 			}
-			*resp_len = len;
+			*resp_len = len - GOODIX_HID_PKG_LEN_SIZE;
 			return 0;
 		}
 
@@ -431,7 +432,7 @@ static int goodix_hid_get_raw_report(struct hid_device *hid,
 	tx_len += args_len;
 
 	/* Step1: write report request info */
-	error = goodix_spi_write(ts, ts->hid_report_addr, tmp_buf, tx_len);
+	error = goodix_spi_write(ts, GOODIX_HID_CMD_ADDR, tmp_buf, tx_len);
 	if (error) {
 		dev_err(ts->dev, "failed send read feature cmd, %d", error);
 		return error;
@@ -446,9 +447,12 @@ static int goodix_hid_get_raw_report(struct hid_device *hid,
 	if (error)
 		return error;
 
-	len = min(len, response_data_len - GOODIX_HID_PKG_LEN_SIZE);
+	/* Empty reprot response */
+	if (!response_data_len)
+		return 0;
+	len = min(len, response_data_len);
 	/* Step3: read response data(skip 2bytes of hid pkg length) */
-	error = goodix_spi_read(ts, ts->hid_report_addr +
+	error = goodix_spi_read(ts, GOODIX_HID_CMD_ADDR +
 				GOODIX_HID_ACK_HEADER_SIZE +
 				GOODIX_HID_PKG_LEN_SIZE, buf, len);
 	if (error) {
@@ -518,7 +522,7 @@ static int goodix_hid_set_raw_report(struct hid_device *hid,
 	memcpy(tmp_buf + tx_len, buf, len);
 	tx_len += len;
 
-	error = goodix_spi_write(ts, ts->hid_report_addr, tmp_buf, tx_len);
+	error = goodix_spi_write(ts, GOODIX_HID_CMD_ADDR, tmp_buf, tx_len);
 	if (error) {
 		dev_err(ts->dev, "failed send report: %*ph", tx_len, tmp_buf);
 		return error;
@@ -749,7 +753,7 @@ static int goodix_spi_set_power(struct goodix_ts_data *ts, int power_state)
 	power_control_cmd[5] = power_state;
 
 	guard(mutex)(&ts->hid_request_lock);
-	error = goodix_spi_write(ts, ts->hid_report_addr, power_control_cmd,
+	error = goodix_spi_write(ts, GOODIX_HID_CMD_ADDR, power_control_cmd,
 				 sizeof(power_control_cmd));
 	if (error) {
 		dev_err(ts->dev, "failed set power mode: %s",
-- 
2.43.0