diff options
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/dw_mmc.c | 41 |
1 files changed, 38 insertions, 3 deletions
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index cf8511b80782..af40d227bece 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -627,6 +627,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot) { struct dw_mci *host = slot->host; u32 div; + u32 clk_en_a; if (slot->clock != host->current_speed) { div = host->bus_hz / slot->clock; @@ -659,9 +660,11 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot) mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0); - /* enable clock */ - mci_writel(host, CLKENA, ((SDMMC_CLKEN_ENABLE | - SDMMC_CLKEN_LOW_PWR) << slot->id)); + /* enable clock; only low power if no SDIO */ + clk_en_a = SDMMC_CLKEN_ENABLE << slot->id; + if (!(mci_readl(host, INTMASK) & SDMMC_INT_SDIO(slot->id))) + clk_en_a |= SDMMC_CLKEN_LOW_PWR << slot->id; + mci_writel(host, CLKENA, clk_en_a); /* inform CIU */ mci_send_cmd(slot, @@ -862,6 +865,30 @@ static int dw_mci_get_cd(struct mmc_host *mmc) return present; } +/* + * Disable lower power mode. + * + * Low power mode will stop the card clock when idle. According to the + * description of the CLKENA register we should disable low power mode + * for SDIO cards if we need SDIO interrupts to work. + * + * This function is fast if low power mode is already disabled. + */ +static void dw_mci_disable_low_power(struct dw_mci_slot *slot) +{ + struct dw_mci *host = slot->host; + u32 clk_en_a; + const u32 clken_low_pwr = SDMMC_CLKEN_LOW_PWR << slot->id; + + clk_en_a = mci_readl(host, CLKENA); + + if (clk_en_a & clken_low_pwr) { + mci_writel(host, CLKENA, clk_en_a & ~clken_low_pwr); + mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | + SDMMC_CMD_PRV_DAT_WAIT, 0); + } +} + static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb) { struct dw_mci_slot *slot = mmc_priv(mmc); @@ -871,6 +898,14 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb) /* Enable/disable Slot Specific SDIO interrupt */ int_mask = mci_readl(host, INTMASK); if (enb) { + /* + * Turn off low power mode if it was enabled. This is a bit of + * a heavy operation and we disable / enable IRQs a lot, so + * we'll leave low power mode disabled and it will get + * re-enabled again in dw_mci_setup_bus(). + */ + dw_mci_disable_low_power(slot); + mci_writel(host, INTMASK, (int_mask | SDMMC_INT_SDIO(slot->id))); } else { |