From 0397526d6ae2518b6c53efd1ff1e81b7d24c91da Mon Sep 17 00:00:00 2001 From: Zhangfei Gao Date: Mon, 20 Sep 2010 15:15:18 -0400 Subject: [PATCH] mmc: SDHC 3.0: correct f_min calculation for SD 3.0 spec While we're at it, add symbols for SDHCI_MAX_DIV_SPEC_{200,300}. Signed-off-by: Zhangfei Gao Signed-off-by: Chris Ball --- drivers/mmc/host/sdhci.c | 8 +++++--- drivers/mmc/host/sdhci.h | 7 +++++++ 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index ac8b12b18fa..e3c9153a87e 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1006,14 +1006,14 @@ static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) if (host->max_clk <= clock) div = 1; else { - for (div = 2; div < 2046; div += 2) { + for (div = 2; div < SDHCI_MAX_DIV_SPEC_300; div += 2) { if ((host->max_clk / div) <= clock) break; } } } else { /* Version 2.00 divisors must be a power of 2. */ - for (div = 1; div < 256; div *= 2) { + for (div = 1; div < SDHCI_MAX_DIV_SPEC_200; div *= 2) { if ((host->max_clk / div) <= clock) break; } @@ -1835,8 +1835,10 @@ int sdhci_add_host(struct sdhci_host *host) mmc->ops = &sdhci_ops; if (host->ops->get_min_clock) mmc->f_min = host->ops->get_min_clock(host); + else if (host->version >= SDHCI_SPEC_300) + mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300; else - mmc->f_min = host->max_clk / 256; + mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200; mmc->f_max = host->max_clk; mmc->caps |= MMC_CAP_SDIO_IRQ; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index ae28a310a6a..112543ae36c 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -185,6 +185,13 @@ #define SDHCI_SPEC_200 1 #define SDHCI_SPEC_300 2 +/* + * End of controller registers. + */ + +#define SDHCI_MAX_DIV_SPEC_200 256 +#define SDHCI_MAX_DIV_SPEC_300 2046 + struct sdhci_ops; struct sdhci_host { -- 2.20.1