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From 1123bcc35585a13cc25c6802f8d3968d185d7f9a Mon Sep 17 00:00:00 2001
From: Markus Proeller <markus.proeller@pieye.org>
Date: Tue, 16 Jun 2020 13:24:31 +0200
Subject: [PATCH] media: irs1125: Using i2c_transfer for ic2 reads
Reading data over i2c is done by using i2c_transfer to ensure that this
operation can't be interrupted.
Signed-off-by: Markus Proeller <markus.proeller@pieye.org>
---
drivers/media/i2c/irs1125.c | 37 ++++++++++++++++++++++---------------
1 file changed, 22 insertions(+), 15 deletions(-)
--- a/drivers/media/i2c/irs1125.c
+++ b/drivers/media/i2c/irs1125.c
@@ -248,27 +248,34 @@ static int irs1125_write(struct v4l2_sub
static int irs1125_read(struct v4l2_subdev *sd, u16 reg, u16 *val)
{
- int ret;
- unsigned char data_w[2] = { reg >> 8, reg & 0xff };
- char rdval[2];
-
struct i2c_client *client = v4l2_get_subdevdata(sd);
+ struct i2c_msg msgs[2];
+ u8 addr_buf[2] = { reg >> 8, reg & 0xff };
+ u8 data_buf[2] = { 0, };
+ int ret;
- ret = i2c_master_send(client, data_w, 2);
- if (ret < 0) {
- dev_dbg(&client->dev, "%s: i2c write error, reg: %x\n",
- __func__, reg);
+ /* Write register address */
+ msgs[0].addr = client->addr;
+ msgs[0].flags = 0;
+ msgs[0].len = ARRAY_SIZE(addr_buf);
+ msgs[0].buf = addr_buf;
+
+ /* Read data from register */
+ msgs[1].addr = client->addr;
+ msgs[1].flags = I2C_M_RD;
+ msgs[1].len = 2;
+ msgs[1].buf = data_buf;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret != ARRAY_SIZE(msgs)) {
+ if (ret >= 0)
+ ret = -EIO;
return ret;
}
- ret = i2c_master_recv(client, rdval, 2);
- if (ret < 0)
- dev_err(&client->dev, "%s: i2c read error, reg: %x\n",
- __func__, reg);
-
- *val = rdval[1] | (rdval[0] << 8);
+ *val = data_buf[1] | (data_buf[0] << 8);
- return ret;
+ return 0;
}
static int irs1125_write_array(struct v4l2_subdev *sd,
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