[PATCH v2 1/2] mmc: sdhci-bcm2835: Clean up platform allocations if sdhci init fails.

Signed-off-by: Eric Anholt <redacted>
---
 drivers/mmc/host/sdhci-bcm2835.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c
index 0ef0343..32f4046 100644
--- a/drivers/mmc/host/sdhci-bcm2835.c
+++ b/drivers/mmc/host/sdhci-bcm2835.c

@@ -173,8 +173,11 @@ static int bcm2835_sdhci_probe(struct platform_device *pdev)
 		goto err;
 	}
 
-	return sdhci_add_host(host);
+	ret = sdhci_add_host(host);
+	if (ret)
+		goto err;
 
+	return 0;
 err:
 	sdhci_pltfm_free(pdev);
 	return ret;

-- 
2.1.4

We're currently using a fixed frequency clock specified in the DT, so
enabling is a no-op.  However, the RPi firmware-based clocks driver
can actually disable unused clocks, so when switching to use it we
ended up losing our MMC clock once all devices were probed.

Signed-off-by: Eric Anholt <redacted>
---

v2: Re-disable our clock on sdhci_add_host() failure.

 drivers/mmc/host/sdhci-bcm2835.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c
index 32f4046..1c65d46 100644
--- a/drivers/mmc/host/sdhci-bcm2835.c
+++ b/drivers/mmc/host/sdhci-bcm2835.c

@@ -172,12 +172,19 @@ static int bcm2835_sdhci_probe(struct platform_device *pdev)
 		ret = PTR_ERR(pltfm_host->clk);
 		goto err;
 	}
+	ret = clk_prepare_enable(pltfm_host->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable host clk\n");
+		goto err;
+	}
 
 	ret = sdhci_add_host(host);
 	if (ret)
-		goto err;
+		goto err_clk;
 
 	return 0;
+err_clk:
+	clk_disable_unprepare(pltfm_host->clk);
 err:
 	sdhci_pltfm_free(pdev);
 	return ret;

-- 
2.1.4

On 29 May 2015 at 23:06, Eric Anholt [off-list ref] wrote:

We're currently using a fixed frequency clock specified in the DT, so
enabling is a no-op.  However, the RPi firmware-based clocks driver
can actually disable unused clocks, so when switching to use it we
ended up losing our MMC clock once all devices were probed.

Signed-off-by: Eric Anholt <redacted>

Thanks, applied!

Kind regards
Uffe

On 29 May 2015 at 23:06, Eric Anholt [off-list ref] wrote:

Signed-off-by: Eric Anholt <redacted>

Thanks, applied!

Kind regards
Uffe

On 05/29/2015 03:06 PM, Eric Anholt wrote:

We're currently using a fixed frequency clock specified in the DT, so
enabling is a no-op.  However, the RPi firmware-based clocks driver
can actually disable unused clocks, so when switching to use it we
ended up losing our MMC clock once all devices were probed.

+	ret = clk_prepare_enable(pltfm_host->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable host clk\n");
+		goto err;
+	}

Given that pltfm_host is a "struct sdhci_pltfm_host" i.e. a type
defined/handled by sdhci-pltfm.c , I'm rather surprised that
sdhci-pltfm.c doesn't do this itself. Wouldn't it make sense for it to
do so?

On 5 June 2015 at 04:59, Stephen Warren [off-list ref] wrote:

On 05/29/2015 03:06 PM, Eric Anholt wrote:

quoted

We're currently using a fixed frequency clock specified in the DT, so
enabling is a no-op.  However, the RPi firmware-based clocks driver
can actually disable unused clocks, so when switching to use it we
ended up losing our MMC clock once all devices were probed.

quoted

diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c

quoted

+     ret = clk_prepare_enable(pltfm_host->clk);
+     if (ret) {
+             dev_err(&pdev->dev, "failed to enable host clk\n");
+             goto err;
+     }

Given that pltfm_host is a "struct sdhci_pltfm_host" i.e. a type
defined/handled by sdhci-pltfm.c , I'm rather surprised that
sdhci-pltfm.c doesn't do this itself. Wouldn't it make sense for it to
do so?

We could likely move additional clock management into the sdhci-pltfm.
So we would then remove some duplicated code, but we would potentially
also loose some in flexibility. It's worth an effort to look into.

Please go ahead and have a try. :-)

Kind regards
Uffe