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@xxxxxxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
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 00759ef..c50cee8 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);
--
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project.
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
