Hi, On 24-05-15 20:04, Michal Suchanek wrote:
The function sunxi_mmc_oclk_onoff filters out the SDXC_LOW_POWER_ON flag but never sets it. Set SDXC_LOW_POWER_ON when oclk is disabled.
Nack, looking at the datasheet I do not thing this patch actually does anything, according to the datasheet setting this bit to 1 results in: "Turn off card clock when FSM in IDLE state", iow this does mmc clock gating on idle automatically in hardware, since we completely disable the clock on clock-off by clearing SDXC_CARD_CLOCK_ON setting this bit on clock-off is a nop. We could consider actually setting this to safe power when setting the clock on, for doing that it would be good to look at the android code and see if it ever sets this bit and if so when. WRT CONFIG_MMC_CLKGATE we are probably better off using SDXC_LOW_POWER_ON then that when it is enabled. So maybe we should set SDXC_LOW_POWER_ON based on #ifdef WRT CONFIG_MMC_CLKGATE, and have some way to tell the mmc core to not do clock gating on this host ? Regards, Hans
Signed-off-by: Michal Suchanek <hramrach@xxxxxxxxx> --- drivers/mmc/host/sunxi-mmc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c index 7cdeecd..e957888 100644 --- a/drivers/mmc/host/sunxi-mmc.c +++ b/drivers/mmc/host/sunxi-mmc.c @@ -603,6 +603,8 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en) if (oclk_en) rval |= SDXC_CARD_CLOCK_ON; + else + rval |= SDXC_LOW_POWER_ON; start = jiffies; end = start + msecs_to_jiffies(750);
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