Re: [PATCH v2 2/2] mmc: sdhci-bcm2835: Actually enable the clock

From: Ulf Hansson
Date: Fri Jun 05 2015 - 04:48:29 EST


On 5 June 2015 at 04:59, Stephen Warren <swarren@xxxxxxxxxxxxx> 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-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/