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?