diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c index 0787148ba3ea..4ea11415996d 100644 --- a/drivers/mmc/host/sunxi-mmc.c +++ b/drivers/mmc/host/sunxi-mmc.c @@ -755,7 +755,7 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, { struct mmc_host *mmc = host->mmc; long rate; - u32 rval, clock = ios->clock; + u32 rval, clock = ios->clock, div = 1; int ret; ret = sunxi_mmc_oclk_onoff(host, 0); @@ -768,10 +768,21 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, if (!ios->clock) return 0; - /* 8 bit DDR requires a higher module clock */ + /* + * Under the old timing mode, 8 bit DDR requires the module + * clock to be double the card clock. Under the new timing + * mode, all DDR modes require a doubled module clock. + * + * We currently only support the standard MMC DDR52 mode. + * This block should be updated once support for other DDR + * modes is added. + */ if (ios->timing == MMC_TIMING_MMC_DDR52 && - ios->bus_width == MMC_BUS_WIDTH_8) + (host->use_new_timings || + ios->bus_width == MMC_BUS_WIDTH_8)) { + div = 2; clock <<= 1; + } if (host->use_new_timings) { ret = sunxi_ccu_set_mmc_timing_mode(host->clk_mmc, true); @@ -799,15 +810,10 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, return ret; } - /* clear internal divider */ + /* set internal divider */ rval = mmc_readl(host, REG_CLKCR); rval &= ~0xff; - /* set internal divider for 8 bit eMMC DDR, so card clock is right */ - if (ios->timing == MMC_TIMING_MMC_DDR52 && - ios->bus_width == MMC_BUS_WIDTH_8) { - rval |= 1; - rate >>= 1; - } + rval |= div - 1; mmc_writel(host, REG_CLKCR, rval); if (host->use_new_timings) { @@ -838,7 +844,7 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, return ret; /* And we just enabled our clock back */ - mmc->actual_clock = rate; + mmc->actual_clock = rate / div; return 0; } @@ -1316,7 +1322,7 @@ static int sunxi_mmc_probe(struct platform_device *pdev) mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED | MMC_CAP_ERASE | MMC_CAP_SDIO_IRQ; - if (host->cfg->clk_delays) + if (host->cfg->clk_delays || host->use_new_timings) mmc->caps |= MMC_CAP_1_8V_DDR; ret = mmc_of_parse(mmc);