From b12d44db4b0187f536c487713ef39a22da990635 Mon Sep 17 00:00:00 2001 From: Ritesh Harjani Date: Mon, 21 Nov 2016 12:07:21 +0530 Subject: [PATCH] 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 Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-msm.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index 00759efed312..c50cee87e6c0 100644 --- a/drivers/mmc/host/sdhci-msm.c +++ b/drivers/mmc/host/sdhci-msm.c @@ -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); -- 2.20.1