[PATCH v3 5/9] input: elants: refactor elants_i2c_execute_command()

["Michał Mirosław" <mirq-linux@rere.qmqm.pl>]

Apply some DRY-ing to elants_i2c_execute_command() callers.  This pulls
polling and error printk()s into a single function.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
---
 drivers/input/touchscreen/elants_i2c.c | 189 +++++++++++++------------
 1 file changed, 96 insertions(+), 93 deletions(-)

diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c
index 87d686ce08f2..b0f083f7f2a9 100644
--- a/drivers/input/touchscreen/elants_i2c.c
+++ b/drivers/input/touchscreen/elants_i2c.c
@@ -205,7 +205,8 @@ static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
 
 static int elants_i2c_execute_command(struct i2c_client *client,
 				      const u8 *cmd, size_t cmd_size,
-				      u8 *resp, size_t resp_size)
+				      u8 *resp, size_t resp_size,
+				      int retries, const char *cmd_name)
 {
 	struct i2c_msg msgs[2];
 	int ret;
@@ -225,30 +226,55 @@ static int elants_i2c_execute_command(struct i2c_client *client,
 		break;
 
 	default:
-		dev_err(&client->dev, "%s: invalid command %*ph\n",
-			__func__, (int)cmd_size, cmd);
+		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
+			cmd_name, (int)cmd_size, cmd);
 		return -EINVAL;
 	}
 
-	msgs[0].addr = client->addr;
-	msgs[0].flags = client->flags & I2C_M_TEN;
-	msgs[0].len = cmd_size;
-	msgs[0].buf = (u8 *)cmd;
+	for (;;) {
+		msgs[0].addr = client->addr;
+		msgs[0].flags = client->flags & I2C_M_TEN;
+		msgs[0].len = cmd_size;
+		msgs[0].buf = (u8 *)cmd;
 
-	msgs[1].addr = client->addr;
-	msgs[1].flags = client->flags & I2C_M_TEN;
-	msgs[1].flags |= I2C_M_RD;
-	msgs[1].len = resp_size;
-	msgs[1].buf = resp;
+		msgs[1].addr = client->addr;
+		msgs[1].flags = client->flags & I2C_M_TEN;
+		msgs[1].flags |= I2C_M_RD;
+		msgs[1].len = resp_size;
+		msgs[1].buf = resp;
 
-	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-	if (ret < 0)
-		return ret;
+		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+		if (ret < 0) {
+			if (--retries > 0) {
+				dev_dbg(&client->dev,
+					"(%s) I2C transfer failed: %d (retrying)\n",
+					cmd_name, ret);
+				continue;
+			}
 
-	if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
-		return -EIO;
+			dev_err(&client->dev,
+				"(%s) I2C transfer failed: %d\n",
+				cmd_name, ret);
+			return ret;
+		}
 
-	return 0;
+		if (ret != ARRAY_SIZE(msgs) ||
+		    resp[FW_HDR_TYPE] != expected_response) {
+			if (--retries > 0) {
+				dev_dbg(&client->dev,
+					"(%s) unexpected response: %*ph (retrying)\n",
+					cmd_name, ret, resp);
+				continue;
+			}
+
+			dev_err(&client->dev,
+				"(%s) unexpected response: %*ph\n",
+				cmd_name, ret, resp);
+			return -EIO;
+		}
+
+		return --retries;
+	}
 }
 
 static int elants_i2c_calibrate(struct elants_data *ts)
@@ -321,27 +347,20 @@ static u16 elants_i2c_parse_version(u8 *buf)
 static int elants_i2c_query_hw_version(struct elants_data *ts)
 {
 	struct i2c_client *client = ts->client;
-	int error, retry_cnt;
+	int retry_cnt = MAX_RETRIES;
 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
 	u8 resp[HEADER_SIZE];
 
-	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
-		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
-						   resp, sizeof(resp));
-		if (!error) {
-			ts->hw_version = elants_i2c_parse_version(resp);
-			if (ts->hw_version != 0xffff)
-				return 0;
-		}
+	while (retry_cnt) {
+		retry_cnt = elants_i2c_execute_command(client, cmd, sizeof(cmd),
+						       resp, sizeof(resp),
+						       retry_cnt, "read fw id");
+		if (retry_cnt < 0)
+			return retry_cnt;
 
-		dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
-			error, (int)sizeof(resp), resp);
-	}
-
-	if (error) {
-		dev_err(&client->dev,
-			"Failed to read fw id: %d\n", error);
-		return error;
+		ts->hw_version = elants_i2c_parse_version(resp);
+		if (ts->hw_version != 0xffff)
+			return 0;
 	}
 
 	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
@@ -352,26 +371,28 @@ static int elants_i2c_query_hw_version(struct elants_data *ts)
 static int elants_i2c_query_fw_version(struct elants_data *ts)
 {
 	struct i2c_client *client = ts->client;
-	int error, retry_cnt;
+	int retry_cnt = MAX_RETRIES;
 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
 	u8 resp[HEADER_SIZE];
 
-	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
-		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
-						   resp, sizeof(resp));
-		if (!error) {
-			ts->fw_version = elants_i2c_parse_version(resp);
-			if (ts->fw_version != 0x0000 &&
-			    ts->fw_version != 0xffff)
-				return 0;
-		}
+	while (retry_cnt) {
+		retry_cnt = elants_i2c_execute_command(client, cmd,
+						       sizeof(cmd),
+						       resp, sizeof(resp),
+						       retry_cnt,
+						       "read fw version");
+		if (retry_cnt < 0)
+			return retry_cnt;
 
-		dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
-			error, (int)sizeof(resp), resp);
+		ts->fw_version = elants_i2c_parse_version(resp);
+		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
+			return 0;
+
+		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
+			(int)sizeof(resp), resp);
 	}
 
-	dev_err(&client->dev,
-		"Failed to read fw version or fw version is invalid\n");
+	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
 
 	return -EINVAL;
 }
@@ -379,25 +400,20 @@ static int elants_i2c_query_fw_version(struct elants_data *ts)
 static int elants_i2c_query_test_version(struct elants_data *ts)
 {
 	struct i2c_client *client = ts->client;
-	int error, retry_cnt;
+	int error;
 	u16 version;
 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
 	u8 resp[HEADER_SIZE];
 
-	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
-		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
-						   resp, sizeof(resp));
-		if (!error) {
-			version = elants_i2c_parse_version(resp);
-			ts->test_version = version >> 8;
-			ts->solution_version = version & 0xff;
+	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
+					   resp, sizeof(resp), MAX_RETRIES,
+					   "read test version");
+	if (error >= 0) {
+		version = elants_i2c_parse_version(resp);
+		ts->test_version = version >> 8;
+		ts->solution_version = version & 0xff;
 
-			return 0;
-		}
-
-		dev_dbg(&client->dev,
-			"read test version error rc=%d, buf=%*phC\n",
-			error, (int)sizeof(resp), resp);
+		return 0;
 	}
 
 	dev_err(&client->dev, "Failed to read test version\n");
@@ -414,13 +430,10 @@ static int elants_i2c_query_bc_version(struct elants_data *ts)
 	int error;
 
 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
-					   resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev,
-			"read BC version error=%d, buf=%*phC\n",
-			error, (int)sizeof(resp), resp);
+					   resp, sizeof(resp), 1,
+					   "read BC version");
+	if (error)
 		return error;
-	}
 
 	version = elants_i2c_parse_version(resp);
 	ts->bc_version = version >> 8;
@@ -452,12 +465,10 @@ static int elants_i2c_query_ts_info(struct elants_data *ts)
 	error = elants_i2c_execute_command(client,
 					   get_resolution_cmd,
 					   sizeof(get_resolution_cmd),
-					   resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev, "get resolution command failed: %d\n",
-			error);
+					   resp, sizeof(resp), 1,
+					   "get resolution");
+	if (error)
 		return error;
-	}
 
 	rows = resp[2] + resp[6] + resp[10];
 	cols = resp[3] + resp[7] + resp[11];
@@ -465,36 +476,29 @@ static int elants_i2c_query_ts_info(struct elants_data *ts)
 	/* Process mm_to_pixel information */
 	error = elants_i2c_execute_command(client,
 					   get_osr_cmd, sizeof(get_osr_cmd),
-					   resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev, "get osr command failed: %d\n",
-			error);
+					   resp, sizeof(resp), 1, "get osr");
+	if (error)
 		return error;
-	}
 
 	osr = resp[3];
 
 	error = elants_i2c_execute_command(client,
 					   get_physical_scan_cmd,
 					   sizeof(get_physical_scan_cmd),
-					   resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev, "get physical scan command failed: %d\n",
-			error);
+					   resp, sizeof(resp), 1,
+					   "get physical scan");
+	if (error)
 		return error;
-	}
 
 	phy_x = get_unaligned_be16(&resp[2]);
 
 	error = elants_i2c_execute_command(client,
 					   get_physical_drive_cmd,
 					   sizeof(get_physical_drive_cmd),
-					   resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev, "get physical drive command failed: %d\n",
-			error);
+					   resp, sizeof(resp), 1,
+					   "get physical drive");
+	if (error)
 		return error;
-	}
 
 	phy_y = get_unaligned_be16(&resp[2]);
 
@@ -649,11 +653,10 @@ static int elants_i2c_validate_remark_id(struct elants_data *ts,
 
 	/* Compare TS Remark ID and FW Remark ID */
 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
-					resp, sizeof(resp));
-	if (error) {
-		dev_err(&client->dev, "failed to query Remark ID: %d\n", error);
+					   resp, sizeof(resp),
+					   1, "read Remark ID");
+	if (error < 0)
 		return error;
-	}
 
 	ts_remark_id = get_unaligned_be16(&resp[3]);
 
-- 
2.20.1