Some SoCs want to adjust the input clock to the DWMMC block as a way of controlling the MMC bus clock. Update the get_mmc_clk() method to support this.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v4: - Update commit message to indicate this patch is for the dw_mmc driver
drivers/mmc/dw_mmc.c | 2 +- drivers/mmc/exynos_dw_mmc.c | 2 +- include/dwmmc.h | 16 +++++++++++++++- 3 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c index 8f28d7e..a034c3f 100644 --- a/drivers/mmc/dw_mmc.c +++ b/drivers/mmc/dw_mmc.c @@ -248,7 +248,7 @@ static int dwmci_setup_bus(struct dwmci_host *host, u32 freq) * host->bus_hz should be set by user. */ if (host->get_mmc_clk) - sclk = host->get_mmc_clk(host); + sclk = host->get_mmc_clk(host, freq); else if (host->bus_hz) sclk = host->bus_hz; else { diff --git a/drivers/mmc/exynos_dw_mmc.c b/drivers/mmc/exynos_dw_mmc.c index e083745..3f702ba 100644 --- a/drivers/mmc/exynos_dw_mmc.c +++ b/drivers/mmc/exynos_dw_mmc.c @@ -39,7 +39,7 @@ static void exynos_dwmci_clksel(struct dwmci_host *host) dwmci_writel(host, DWMCI_CLKSEL, priv->sdr_timing); }
-unsigned int exynos_dwmci_get_clk(struct dwmci_host *host) +unsigned int exynos_dwmci_get_clk(struct dwmci_host *host, uint freq) { unsigned long sclk; int8_t clk_div; diff --git a/include/dwmmc.h b/include/dwmmc.h index 7a7555a..25cf42c 100644 --- a/include/dwmmc.h +++ b/include/dwmmc.h @@ -163,7 +163,21 @@ struct dwmci_host {
void (*clksel)(struct dwmci_host *host); void (*board_init)(struct dwmci_host *host); - unsigned int (*get_mmc_clk)(struct dwmci_host *host); + + /** + * Get / set a particular MMC clock frequency + * + * This is used to request the current clock frequency of the clock + * that drives the DWMMC peripheral. The caller will then use this + * information to work out the divider it needs to achieve the + * required MMC bus clock frequency. If you want to handle the + * clock external to DWMMC, use @freq to select the frequency and + * return that value too. Then DWMMC will put itself in bypass mode. + * + * @host: DWMMC host + * @freq: Frequency the host is trying to achieve + */ + unsigned int (*get_mmc_clk)(struct dwmci_host *host, uint freq);
struct mmc_config cfg; };