diff options
Diffstat (limited to 'drivers/iio/adc/mcp3422.c')
| -rw-r--r-- | drivers/iio/adc/mcp3422.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c index 63de705086ed..9ac2becde8f2 100644 --- a/drivers/iio/adc/mcp3422.c +++ b/drivers/iio/adc/mcp3422.c @@ -99,16 +99,12 @@ 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; } @@ -141,6 +137,8 @@ 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; @@ -148,12 +146,18 @@ 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, |