Re: [PATCH] mmc: pxamci: Fix passing NULL to PTR_ERR() in pxamci_probe()

[Dan Carpenter <dan.carpenter@linaro.org>]

On Mon, Oct 13, 2025 at 04:54:13PM -0600, Khalid Aziz wrote:
> > @@ -703,20 +705,15 @@ static int pxamci_probe(struct platform_device *pdev)
> >   	platform_set_drvdata(pdev, mmc);
> > -	host->dma_chan_rx = dma_request_chan(dev, "rx");
> > -	if (IS_ERR(host->dma_chan_rx)) {
> > -		host->dma_chan_rx = NULL;
> > +	host->dma_chan_rx = devm_dma_request_chan(dev, "rx");
> > +	if (IS_ERR(host->dma_chan_rx))
> >   		return dev_err_probe(dev, PTR_ERR(host->dma_chan_rx),
> >   				     "unable to request rx dma channel\n");
> > -	}
> > -	host->dma_chan_tx = dma_request_chan(dev, "tx");
> > -	if (IS_ERR(host->dma_chan_tx)) {
> > -		dev_err(dev, "unable to request tx dma channel\n");
> > -		ret = PTR_ERR(host->dma_chan_tx);
> > -		host->dma_chan_tx = NULL;
> > -		goto out;
> > -	}
> > +	host->dma_chan_tx = devm_dma_request_chan(dev, "tx");
> > +	if (IS_ERR(host->dma_chan_tx))
> > +		return dev_err_probe(dev, PTR_ERR(host->dma_chan_tx),
> > +				     "unable to request tx dma channel\n");
> 
> We should still release DMA rx channel before returning here.
> 
> >   	if (host->pdata) {
> >   		host->detect_delay_ms = host->pdata->detect_delay_ms;
> > @@ -724,25 +721,21 @@ static int pxamci_probe(struct platform_device *pdev)
> >   		host->power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
> >   		if (IS_ERR(host->power)) {
> >   			ret = PTR_ERR(host->power);
> > -			dev_err(dev, "Failed requesting gpio_power\n");
> > -			goto out;
> > +			return dev_err_probe(dev, ret, "Failed requesting gpio_power\n");
> 
> Don't we need to release DMA Rx and Tx channels before we return from here?
> 
> >   		}
> >   		/* FIXME: should we pass detection delay to debounce? */
> >   		ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0);
> > -		if (ret && ret != -ENOENT) {
> > -			dev_err(dev, "Failed requesting gpio_cd\n");
> > -			goto out;
> > -		}
> > +		if (ret && ret != -ENOENT)
> > +			return dev_err_probe(dev, ret, "Failed requesting gpio_cd\n");
> 
> Same here
> 
> >   		if (!host->pdata->gpio_card_ro_invert)
> >   			mmc->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
> >   		ret = mmc_gpiod_request_ro(mmc, "wp", 0, 0);
> > -		if (ret && ret != -ENOENT) {
> > -			dev_err(dev, "Failed requesting gpio_ro\n");
> > -			goto out;
> > -		}
> > +		if (ret && ret != -ENOENT)
> > +			return dev_err_probe(dev, ret, "Failed requesting gpio_ro\n");
> 
> and here.
> 
> Looking at Documentation/driver-api/driver-model/devres.rst,
> dma_request_chan() is not devres managed interface and thus will not be
> released automatically. Do you agree?
> 

The patch changes dma_request_chan() to devm_dma_request_chan().

regards,
dan carpenter