[PATCH v2] mmc: pxamci: fix the device-tree probe deferral path

[PATCH v2] mmc: pxamci: fix the device-tree probe deferral path

[Robert Jarzmik]

When the gpio driver is probed after the mmc one, the read/write gpio
and card detection one return -EPROBE_DEFER. Unfortunately, the memory
region remains requested, and upon the next probe, the probe will fail
anyway with -EBUSY.

Fix this by releasing the memory resource upon probe failure.

More broadly, this patch uses devm_*() primitives whenever possible in
the probe function.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
---
Since v1: broaden the devm_*() enveloppe
---
 drivers/mmc/host/pxamci.c | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 28a057fae0a1..a672b9259d34 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -654,12 +654,8 @@ static int pxamci_probe(struct platform_device *pdev)
 
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_irq(pdev, 0);
-	if (!r || irq < 0)
-		return -ENXIO;
-
-	r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
-	if (!r)
-		return -EBUSY;
+	if (irq < 0)
+		return irq;
 
 	mmc = mmc_alloc_host(sizeof(struct pxamci_host), &pdev->dev);
 	if (!mmc) {
@@ -727,9 +723,9 @@ static int pxamci_probe(struct platform_device *pdev)
 	host->irq = irq;
 	host->imask = MMC_I_MASK_ALL;
 
-	host->base = ioremap(r->start, SZ_4K);
-	if (!host->base) {
-		ret = -ENOMEM;
+	host->base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(host->base)) {
+		ret = PTR_ERR(host->base);
 		goto out;
 	}
 
@@ -742,7 +738,8 @@ static int pxamci_probe(struct platform_device *pdev)
 	writel(64, host->base + MMC_RESTO);
 	writel(host->imask, host->base + MMC_I_MASK);
 
-	ret = request_irq(host->irq, pxamci_irq, 0, DRIVER_NAME, host);
+	ret = devm_request_irq(&pdev->dev, host->irq, pxamci_irq, 0,
+			       DRIVER_NAME, host);
 	if (ret)
 		goto out;
 
@@ -833,14 +830,11 @@ out:
 			dma_release_channel(host->dma_chan_rx);
 		if (host->dma_chan_tx)
 			dma_release_channel(host->dma_chan_tx);
-		if (host->base)
-			iounmap(host->base);
 		if (host->clk)
 			clk_put(host->clk);
 	}
 	if (mmc)
 		mmc_free_host(mmc);
-	release_resource(r);
 	return ret;
 }
 
@@ -870,17 +864,13 @@ static int pxamci_remove(struct platform_device *pdev)
 		       END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
 		       host->base + MMC_I_MASK);
 
-		free_irq(host->irq, host);
 		dmaengine_terminate_all(host->dma_chan_rx);
 		dmaengine_terminate_all(host->dma_chan_tx);
 		dma_release_channel(host->dma_chan_rx);
 		dma_release_channel(host->dma_chan_tx);
-		iounmap(host->base);
 
 		clk_put(host->clk);
 
-		release_resource(host->res);
-
 		mmc_free_host(mmc);
 	}
 	return 0;
-- 
2.1.4

Re: [PATCH v2] mmc: pxamci: fix the device-tree probe deferral path

[Ulf Hansson]

On 6 February 2016 at 22:14, Robert Jarzmik <robert.jarzmik@free.fr> wrote:
> When the gpio driver is probed after the mmc one, the read/write gpio
> and card detection one return -EPROBE_DEFER. Unfortunately, the memory
> region remains requested, and upon the next probe, the probe will fail
> anyway with -EBUSY.
>
> Fix this by releasing the memory resource upon probe failure.
>
> More broadly, this patch uses devm_*() primitives whenever possible in
> the probe function.

There's actually also clocks and regulators that may be converted to
use the devm* functions.
Do you want to do that as a part of this patch as well? Otherwise I
can apply as is.

Kind regards
Uffe

>
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> ---
> Since v1: broaden the devm_*() enveloppe
> ---
>  drivers/mmc/host/pxamci.c | 24 +++++++-----------------
>  1 file changed, 7 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
> index 28a057fae0a1..a672b9259d34 100644
> --- a/drivers/mmc/host/pxamci.c
> +++ b/drivers/mmc/host/pxamci.c
> @@ -654,12 +654,8 @@ static int pxamci_probe(struct platform_device *pdev)
>
>         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>         irq = platform_get_irq(pdev, 0);
> -       if (!r || irq < 0)
> -               return -ENXIO;
> -
> -       r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
> -       if (!r)
> -               return -EBUSY;
> +       if (irq < 0)
> +               return irq;
>
>         mmc = mmc_alloc_host(sizeof(struct pxamci_host), &pdev->dev);
>         if (!mmc) {
> @@ -727,9 +723,9 @@ static int pxamci_probe(struct platform_device *pdev)
>         host->irq = irq;
>         host->imask = MMC_I_MASK_ALL;
>
> -       host->base = ioremap(r->start, SZ_4K);
> -       if (!host->base) {
> -               ret = -ENOMEM;
> +       host->base = devm_ioremap_resource(&pdev->dev, r);
> +       if (IS_ERR(host->base)) {
> +               ret = PTR_ERR(host->base);
>                 goto out;
>         }
>
> @@ -742,7 +738,8 @@ static int pxamci_probe(struct platform_device *pdev)
>         writel(64, host->base + MMC_RESTO);
>         writel(host->imask, host->base + MMC_I_MASK);
>
> -       ret = request_irq(host->irq, pxamci_irq, 0, DRIVER_NAME, host);
> +       ret = devm_request_irq(&pdev->dev, host->irq, pxamci_irq, 0,
> +                              DRIVER_NAME, host);
>         if (ret)
>                 goto out;
>
> @@ -833,14 +830,11 @@ out:
>                         dma_release_channel(host->dma_chan_rx);
>                 if (host->dma_chan_tx)
>                         dma_release_channel(host->dma_chan_tx);
> -               if (host->base)
> -                       iounmap(host->base);
>                 if (host->clk)
>                         clk_put(host->clk);
>         }
>         if (mmc)
>                 mmc_free_host(mmc);
> -       release_resource(r);
>         return ret;
>  }
>
> @@ -870,17 +864,13 @@ static int pxamci_remove(struct platform_device *pdev)
>                        END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
>                        host->base + MMC_I_MASK);
>
> -               free_irq(host->irq, host);
>                 dmaengine_terminate_all(host->dma_chan_rx);
>                 dmaengine_terminate_all(host->dma_chan_tx);
>                 dma_release_channel(host->dma_chan_rx);
>                 dma_release_channel(host->dma_chan_tx);
> -               iounmap(host->base);
>
>                 clk_put(host->clk);
>
> -               release_resource(host->res);
> -
>                 mmc_free_host(mmc);
>         }
>         return 0;
> --
> 2.1.4
>

Re: [PATCH v2] mmc: pxamci: fix the device-tree probe deferral path

[Robert Jarzmik]

Ulf Hansson <ulf.hansson@linaro.org> writes:

> On 6 February 2016 at 22:14, Robert Jarzmik <robert.jarzmik@free.fr> wrote:
>> When the gpio driver is probed after the mmc one, the read/write gpio
>> and card detection one return -EPROBE_DEFER. Unfortunately, the memory
>> region remains requested, and upon the next probe, the probe will fail
>> anyway with -EBUSY.
>>
>> Fix this by releasing the memory resource upon probe failure.
>>
>> More broadly, this patch uses devm_*() primitives whenever possible in
>> the probe function.
>
> There's actually also clocks and regulators that may be converted to
> use the devm* functions.
> Do you want to do that as a part of this patch as well? Otherwise I
> can apply as is.
Yes, I will add the regulator and clock in this patch, you're right, this makes
sense to me, v3 on its way.

Cheers.

--
Robert