mmc: sdhci: make max-frequency property in device tree work (59241757) · Commits · 戴 / test

Device tree provides option to specify the max freqency with property "max-frequency" in dts and common parse function mmc_of_parse() will parse it and use this value to set host->f_max to tell the MMC core the maxinum frequency the host works. However, current sdhci driver will finally overwrite this value with host->max_clk regardless of the max-frequency property. This patch makes sure not overwrite the max-frequency set from device tree and do basic sanity check. Signed-off-by:

Dong Aisheng <aisheng.dong@freescale.com> Reviewed-by:

Johan Derycke <johan.derycke@barco.com> Signed-off-by:

Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -2866,6 +2866,7 @@ int sdhci_add_host(struct sdhci_host *host)
		u32 max_current_caps;
		unsigned int ocr_avail;
		unsigned int override_timeout_clk;
		u32 max_clk;
		int ret;

		WARN_ON(host == NULL);
		@@ -3050,18 +3051,22 @@ int sdhci_add_host(struct sdhci_host *host)
		* Set host parameters.
		*/
		mmc->ops = &sdhci_ops;
		mmc->f_max = host->max_clk;
		max_clk = host->max_clk;

		if (host->ops->get_min_clock)
		mmc->f_min = host->ops->get_min_clock(host);
		else if (host->version >= SDHCI_SPEC_300) {
		if (host->clk_mul) {
		mmc->f_min = (host->max_clk * host->clk_mul) / 1024;
		mmc->f_max = host->max_clk * host->clk_mul;
		max_clk = host->max_clk * host->clk_mul;
		} else
		mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300;
		} else
		mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200;

		if (!mmc->f_max \|\| (mmc->f_max && (mmc->f_max > max_clk)))
		mmc->f_max = max_clk;

		if (!(host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)) {
		host->timeout_clk = (caps[0] & SDHCI_TIMEOUT_CLK_MASK) >>
		SDHCI_TIMEOUT_CLK_SHIFT;

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