[PATCH 1/3] iio: adc: ti_am335x_adc: alloc channels via devm_kcalloc()

Alexandru Ardelean
2020-04-28T11:14:24Z

This change attaches the life-cycle of the channels array to the parent
device object that is attached to the IIO device.
This way we can remove from the cleanup code, the explicit
tiadc_channels_remove() which simply does a kfree() on the channels array.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---

The reason I'm targetting this driver, is because it's among the few
places where 'indio_dev->buffer' is accessed directly in the driver, and
that makes it difficult to think of a sane-backwards-compatible way to
do multiple IIO buffers.

drivers/iio/adc/ti_am335x_adc.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 9d984f2a8ba7..d932fe383a24 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -428,7 +428,8 @@ static const char * const chan_name_ain[] = {
"AIN7",
};

-static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
+static int tiadc_channel_init(struct device *dev, struct iio_dev *indio_dev,
+ int channels)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
struct iio_chan_spec *chan_array;
@@ -436,7 +437,8 @@ static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
int i;

indio_dev->num_channels = channels;
- chan_array = kcalloc(channels, sizeof(*chan_array), GFP_KERNEL);
+ chan_array = devm_kcalloc(dev, channels, sizeof(*chan_array),
+ GFP_KERNEL);
if (chan_array == NULL)
return -ENOMEM;

@@ -459,11 +461,6 @@ static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
return 0;
}

-static void tiadc_channels_remove(struct iio_dev *indio_dev)
-{
- kfree(indio_dev->channels);
-}
-
static int tiadc_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
@@ -635,7 +632,7 @@ static int tiadc_probe(struct platform_device *pdev)
tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD);
mutex_init(&adc_dev->fifo1_lock);

- err = tiadc_channel_init(indio_dev, adc_dev->channels);
+ err = tiadc_channel_init(&pdev->dev, indio_dev, adc_dev->channels);
if (err < 0)
return err;

@@ -666,7 +663,6 @@ static int tiadc_probe(struct platform_device *pdev)
err_buffer_unregister:
tiadc_iio_buffered_hardware_remove(indio_dev);
err_free_channels:
- tiadc_channels_remove(indio_dev);
return err;
}

@@ -684,7 +680,6 @@ static int tiadc_remove(struct platform_device *pdev)
}
iio_device_unregister(indio_dev);
tiadc_iio_buffered_hardware_remove(indio_dev);
- tiadc_channels_remove(indio_dev);

step_en = get_adc_step_mask(adc_dev);
am335x_tsc_se_clr(adc_dev->mfd_tscadc, step_en);
--
2.17.1