iio: adc: ti_am335x_adc: Fix return value check of tiadc_request_dma()

Fix wrong handling of a DMA request where the probing only failed
if -EPROPE_DEFER was returned. Instead, let us fail if a non -ENODEV
value is returned. This makes DMAs explicitly optional. Even if the
DMA request is unsuccessfully, the ADC can still work properly.
We do also handle the defer probe case by making use of dev_err_probe().

Fixes: f438b9da75eb ("drivers: iio: ti_am335x_adc: add dma support")
Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
Reviewed-by: Bhavya Kapoor <b-kapoor@ti.com>
Link: https://lore.kernel.org/r/20230925134427.214556-1-w.egorov@phytec.de
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index c755e8cd52205cb606f6d46650133cc5a2d2d8e6..95fa857e8aadfe3a88d9db85fd70940ff7c624ed 100644 (file)
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -670,8 +670,10 @@ static int tiadc_probe(struct platform_device *pdev)
        platform_set_drvdata(pdev, indio_dev);
 
        err = tiadc_request_dma(pdev, adc_dev);
-       if (err && err == -EPROBE_DEFER)
+       if (err && err != -ENODEV) {
+               dev_err_probe(&pdev->dev, err, "DMA request failed\n");
                goto err_dma;
+       }
 
        return 0;