summaryrefslogtreecommitdiff
path: root/drivers/iio/adc/mcp3422.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/iio/adc/mcp3422.c')
-rw-r--r--drivers/iio/adc/mcp3422.c16
1 files changed, 10 insertions, 6 deletions
diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c
index 5f1706d1c3c0..da353dcb1e9d 100644
--- a/drivers/iio/adc/mcp3422.c
+++ b/drivers/iio/adc/mcp3422.c
@@ -96,16 +96,12 @@ static int mcp3422_update_config(struct mcp3422 *adc, u8 newconfig)
{
int ret;
- mutex_lock(&adc->lock);
-
ret = i2c_master_send(adc->i2c, &newconfig, 1);
if (ret > 0) {
adc->config = newconfig;
ret = 0;
}
- mutex_unlock(&adc->lock);
-
return ret;
}
@@ -138,6 +134,8 @@ static int mcp3422_read_channel(struct mcp3422 *adc,
u8 config;
u8 req_channel = channel->channel;
+ mutex_lock(&adc->lock);
+
if (req_channel != MCP3422_CHANNEL(adc->config)) {
config = adc->config;
config &= ~MCP3422_CHANNEL_MASK;
@@ -145,12 +143,18 @@ static int mcp3422_read_channel(struct mcp3422 *adc,
config &= ~MCP3422_PGA_MASK;
config |= MCP3422_PGA_VALUE(adc->pga[req_channel]);
ret = mcp3422_update_config(adc, config);
- if (ret < 0)
+ if (ret < 0) {
+ mutex_unlock(&adc->lock);
return ret;
+ }
msleep(mcp3422_read_times[MCP3422_SAMPLE_RATE(adc->config)]);
}
- return mcp3422_read(adc, value, &config);
+ ret = mcp3422_read(adc, value, &config);
+
+ mutex_unlock(&adc->lock);
+
+ return ret;
}
static int mcp3422_read_raw(struct iio_dev *iio,