On 08/17/2015 02:52 PM, Michal Suchanek wrote:

Hello,

On 17 August 2015 at 03:55, Jaehoon Chung [off-list ref] wrote:

quoted

Hi, Michal.

On 08/12/2015 09:23 PM, Michal Suchanek wrote:

quoted

The driver has open-coded test for SDIO cards. Use the mmc core provided
MMC_QUIRK_BROKEN_CLK_GATING flag instead.

Did you use the clock-gating for SDIO cards?
Doesn't MMC_CAP_SDIO_IRQ bit set? Which case is broken?
Could you explain to me more?

The core flag for disabling power saving is MMC_QUIRK_BROKEN_CLK_GATING.

I understood your intention. And i read the comment into mmc/core/quirks.c
I will test SDIO card with this patch. Thanks.

Best Regards,
Jaehoon Chung

It may coincide with MMC_CAP_SDIO_IRQ but that's different flag for
different purpose.

MMC_QUIRK_BROKEN_CLK_GATING is currently set for all SDIO cards except
for cards on a whitelist.

I don't know any particular SDIO card that has problems when the clock
is off and does not use an IRQ.

Thanks

Michal

quoted

Best Regards,
Jaehoon Chung

quoted

As a bonus this may enable clock gating on SDIO cards that are known to
work with it.

Signed-off-by: Michal Suchanek <redacted>
---
 drivers/mmc/host/dw_mmc.c | 33 +++++++++++++++------------------
 1 file changed, 15 insertions(+), 18 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 40e9d8e..3bc9fd7 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c

@@ -1335,27 +1335,24 @@ static void dw_mci_init_card(struct mmc_host *mmc, struct mmc_card *card)
       * description of the CLKENA register we should disable low power mode
       * for SDIO cards if we need SDIO interrupts to work.
       */
-     if (mmc->caps & MMC_CAP_SDIO_IRQ) {
-             const u32 clken_low_pwr = SDMMC_CLKEN_LOW_PWR << slot->id;
-             u32 clk_en_a_old;
-             u32 clk_en_a;
+     const u32 clken_low_pwr = SDMMC_CLKEN_LOW_PWR << slot->id;
+     u32 clk_en_a_old;
+     u32 clk_en_a;

-             clk_en_a_old = mci_readl(host, CLKENA);
+     clk_en_a_old = mci_readl(host, CLKENA);

-             if (card->type == MMC_TYPE_SDIO ||
-                 card->type == MMC_TYPE_SD_COMBO) {
-                     set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
-                     clk_en_a = clk_en_a_old & ~clken_low_pwr;
-             } else {
-                     clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
-                     clk_en_a = clk_en_a_old | clken_low_pwr;
-             }
+     if (card->quirks & MMC_QUIRK_BROKEN_CLK_GATING) {
+             set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
+             clk_en_a = clk_en_a_old & ~clken_low_pwr;
+     } else {
+             clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
+             clk_en_a = clk_en_a_old | clken_low_pwr;
+     }

-             if (clk_en_a != clk_en_a_old) {
-                     mci_writel(host, CLKENA, clk_en_a);
-                     mci_send_cmd(slot, SDMMC_CMD_UPD_CLK |
-                                  SDMMC_CMD_PRV_DAT_WAIT, 0);
-             }
+     if (clk_en_a != clk_en_a_old) {
+             mci_writel(host, CLKENA, clk_en_a);
+             mci_send_cmd(slot, SDMMC_CMD_UPD_CLK |
+                             SDMMC_CMD_PRV_DAT_WAIT, 0);
      }
 }

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