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mmc: sdhci-msm: Add clock changes for DDR mode. 

SDHC MSM controller need 2x clock for MCLK at GCC.
Hence make required changes to have 2x clock for
DDR timing modes.

Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Ritesh Harjani 2016-11-21 12:07:21 +05:30 committed by Ulf Hansson
parent edc609fd19
commit b12d44db4b
1 changed files with 17 additions and 4 deletions
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21
drivers/mmc/host/sdhci-msm.c
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@ -610,6 +610,7 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
struct mmc_ios curr_ios = host->mmc->ios;
int rc;
if (!clock) {
@ -618,16 +619,28 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
}
spin_unlock_irq(&host->lock);
/*
* The SDHC requires internal clock frequency to be double the
* actual clock that will be set for DDR mode. The controller
* uses the faster clock(100/400MHz) for some of its parts and
* send the actual required clock (50/200MHz) to the card.
*/
if (curr_ios.timing == MMC_TIMING_UHS_DDR50 ||
curr_ios.timing == MMC_TIMING_MMC_DDR52 ||
curr_ios.timing == MMC_TIMING_MMC_HS400)
clock *= 2;
rc = clk_set_rate(msm_host->clk, clock);
if (rc) {
pr_err("%s: Failed to set clock at rate %u\n",
mmc_hostname(host->mmc), clock);
pr_err("%s: Failed to set clock at rate %u at timing %d\n",
mmc_hostname(host->mmc), clock,
curr_ios.timing);
goto out_lock;
}
msm_host->clk_rate = clock;
pr_debug("%s: Setting clock at rate %lu\n",
mmc_hostname(host->mmc), clk_get_rate(msm_host->clk));
pr_debug("%s: Setting clock at rate %lu at timing %d\n",
mmc_hostname(host->mmc), clk_get_rate(msm_host->clk),
curr_ios.timing);
out_lock:
spin_lock_irq(&host->lock);