[PATCH 4.4 043/137] iio:adc:ti_am335x_adc Fix buffered mode by identifying as software buffer.

Greg Kroah-Hartman
2016-02-24T04:47:09Z

From: Jonathan Cameron <jic23@kernel.org>

commit 9d0be85d4e2cfa2519ae16efe7ff4a7150c43c0b upstream.

Whilst this part has a hardware buffer, the identifcation that IIO cares
about is the userspace facing end. It this case we push individual elements
from the hardware fifo into the software interface (specifically a kfifo)
rather than providing direct reads through to a hardware buffer
(as we still do in the sca3000 for example).

Technically the original specification as a hardware buffer could be
considered wrong, but it didn't matter until the patch listed below.

Result is that any attempt to enable the buffer will return -EINVAL

Fixes: 225d59adf1c8 ("iio: Specify supported modes for buffers")
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/iio/adc/ti_am335x_adc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -289,7 +289,7 @@ static int tiadc_iio_buffered_hardware_s
goto error_kfifo_free;

indio_dev->setup_ops = setup_ops;
- indio_dev->modes |= INDIO_BUFFER_HARDWARE;
+ indio_dev->modes |= INDIO_BUFFER_SOFTWARE;

return 0;