linux-kernel - [PATCH v2 1/4] iio: vcnl4000: Factorize data reading and writing.

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Message-Id: <20200406145356.25883-2-m.othacehe@gmail.com>
Date:   Mon,  6 Apr 2020 16:53:53 +0200
From:   Mathieu Othacehe <m.othacehe@...il.com>
To:     jic23@...nel.org, knaack.h@....de, lars@...afoo.de,
        pmeerw@...erw.net
Cc:     linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org,
        Mathieu Othacehe <m.othacehe@...il.com>
Subject: [PATCH v2 1/4] iio: vcnl4000: Factorize data reading and writing.

Factorize data reading in vcnl4000_measure into a vcnl4000_read_block_data
function. Use it to provide a vcnl4000_read_data function that is able to
read sensor data under lock. Also add a vcnl4000_write_data function.

Signed-off-by: Mathieu Othacehe <m.othacehe@...il.com>
---
 drivers/iio/light/vcnl4000.c | 54 +++++++++++++++++++++++++++++++++---
 1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index e5b00a6611ac..c95b89740dfa 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -189,11 +189,59 @@ static int vcnl4200_init(struct vcnl4000_data *data)
 	return 0;
 };
 
+static int vcnl4000_read_block_data(struct vcnl4000_data *data, u8 data_reg,
+				    int *val)
+{
+	__be16 buf;
+	int ret;
+
+	ret = i2c_smbus_read_i2c_block_data(data->client,
+		data_reg, sizeof(buf), (u8 *) &buf);
+	if (ret < 0)
+		goto end;
+
+	*val = be16_to_cpu(buf);
+end:
+	return ret;
+}
+
+static int vcnl4000_read_data(struct vcnl4000_data *data, u8 data_reg,
+			      int *val)
+{
+	int ret;
+
+	mutex_lock(&data->vcnl4000_lock);
+	ret = vcnl4000_read_block_data(data, data_reg, val);
+	mutex_unlock(&data->vcnl4000_lock);
+
+	return ret;
+}
+
+static int vcnl4000_write_data(struct vcnl4000_data *data, u8 data_reg,
+			       u16 val)
+{
+	int ret;
+
+	if (val > U16_MAX)
+		return -ERANGE;
+
+	mutex_lock(&data->vcnl4000_lock);
+
+	ret = i2c_smbus_write_byte_data(data->client, data_reg, val >> 8);
+	if (ret < 0)
+		goto end;
+
+	ret = i2c_smbus_write_byte_data(data->client, data_reg + 1, val);
+end:
+	mutex_unlock(&data->vcnl4000_lock);
+
+	return ret;
+}
+
 static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
 				u8 rdy_mask, u8 data_reg, int *val)
 {
 	int tries = 20;
-	__be16 buf;
 	int ret;
 
 	mutex_lock(&data->vcnl4000_lock);
@@ -220,13 +268,11 @@ static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
 		goto fail;
 	}
 
-	ret = i2c_smbus_read_i2c_block_data(data->client,
-		data_reg, sizeof(buf), (u8 *) &buf);
+	ret = vcnl4000_read_block_data(data, data_reg, val);
 	if (ret < 0)
 		goto fail;
 
 	mutex_unlock(&data->vcnl4000_lock);
-	*val = be16_to_cpu(buf);
 
 	return 0;
 
-- 
2.26.0