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Subject[PATCH v3 16/16] bq27x00: Use single i2c_transfer call for property read
Date
From: Grazvydas Ignotas <notasas@gmail.com>

Doing this by using 2 calls sometimes results in unexpected
values being returned on OMAP3 i2c controller.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
drivers/power/bq27x00_battery.c | 27 +++++++++++----------------
1 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/drivers/power/bq27x00_battery.c b/drivers/power/bq27x00_battery.c
index 740a0ac..59e68db 100644
--- a/drivers/power/bq27x00_battery.c
+++ b/drivers/power/bq27x00_battery.c
@@ -565,31 +565,26 @@ static DEFINE_MUTEX(battery_mutex);
static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
{
struct i2c_client *client = to_i2c_client(di->dev);
- struct i2c_msg msg;
+ struct i2c_msg msg[2];
unsigned char data[2];
int ret;

if (!client->adapter)
return -ENODEV;

- msg.addr = client->addr;
- msg.flags = 0;
- msg.len = 1;
- msg.buf = data;
-
- data[0] = reg;
- ret = i2c_transfer(client->adapter, &msg, 1);
-
- if (ret < 0)
- return ret;
-
+ msg[0].addr = client->addr;
+ msg[0].flags = 0;
+ msg[0].buf = &reg;
+ msg[0].len = sizeof(reg);
+ msg[1].addr = client->addr;
+ msg[1].flags = I2C_M_RD;
+ msg[1].buf = data;
if (single)
- msg.len = 1;
+ msg[1].len = 1;
else
- msg.len = 2;
+ msg[1].len = 2;

- msg.flags = I2C_M_RD;
- ret = i2c_transfer(client->adapter, &msg, 1);
+ ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret < 0)
return ret;

--
1.7.2.3


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