| Message ID | 1432933572-8695-2-git-send-email-eric@anholt.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 29 May 2015 at 23:06, Eric Anholt <eric@anholt.net> 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 <eric@anholt.net> Thanks, applied! Kind regards Uffe > --- > > 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 > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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. > diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c > + 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? -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 5 June 2015 at 04:59, Stephen Warren <swarren@wwwdotorg.org> wrote: > 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. > >> diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c > >> + 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 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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;
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 <eric@anholt.net> --- v2: Re-disable our clock on sdhci_add_host() failure. drivers/mmc/host/sdhci-bcm2835.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)