On Tue, 22 Nov 2016 19:48:56 -0800 Jeremy McNicoll wrote: > On 2016-11-22 7:36 PM, Jisheng Zhang wrote: > > On Tue, 22 Nov 2016 17:09:48 -0800 > > Jeremy McNicoll <jeremymc@xxxxxxxxxx> wrote: > > > >> On msm8992 it has been observed that IRQs were not getting > >> ACK'd correctly when clocked at speeds greater than 400KHz. > >> > >> Signed-off-by: Jeremy McNicoll <jeremymc@xxxxxxxxxx> > >> --- > >> drivers/mmc/host/sdhci-msm.c | 7 +++++++ > >> drivers/mmc/host/sdhci.c | 12 ++++++++++-- > >> drivers/mmc/host/sdhci.h | 2 ++ > >> 3 files changed, 19 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c > >> index 1fcda96..459003c 100644 > >> --- a/drivers/mmc/host/sdhci-msm.c > >> +++ b/drivers/mmc/host/sdhci-msm.c > >> @@ -1303,6 +1303,13 @@ static int sdhci_msm_probe(struct platform_device *pdev) > >> CORE_VENDOR_SPEC_CAPABILITIES0); > >> } > >> > >> + /* Enable delayed IRQ handling workaround on 8992 */ > >> + if (core_major == 1 && core_minor == 0x3e) { > >> + /* Add 40us delay in interrupt handler when operating > >> + * at initialization frequency of 400KHz. */ > >> + host->quirks2 |= SDHCI_QUIRK2_SLOW_INT_CLR; > >> + } > >> + > >> /* Setup IRQ for handling power/voltage tasks with PMIC */ > >> msm_host->pwr_irq = platform_get_irq_byname(pdev, "pwr_irq"); > >> if (msm_host->pwr_irq < 0) { > >> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > >> index 5911f98..c1aae22 100644 > >> --- a/drivers/mmc/host/sdhci.c > >> +++ b/drivers/mmc/host/sdhci.c > >> @@ -2703,11 +2703,19 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id) > >> result = IRQ_WAKE_THREAD; > >> } > >> > >> - if (intmask & SDHCI_INT_CMD_MASK) > >> + if (intmask & SDHCI_INT_CMD_MASK) { > >> + if ((host->quirks2 & SDHCI_QUIRK2_SLOW_INT_CLR) && (host->clock <= 400000)) { > >> + udelay(40); > >> + } > >> sdhci_cmd_irq(host, intmask & SDHCI_INT_CMD_MASK); > >> + } > >> > >> - if (intmask & SDHCI_INT_DATA_MASK) > >> + if (intmask & SDHCI_INT_DATA_MASK) { > >> + if ((host->quirks2 & SDHCI_QUIRK2_SLOW_INT_CLR) && (host->clock <= 400000)) { > >> + udelay(40); > >> + } > >> sdhci_data_irq(host, intmask & SDHCI_INT_DATA_MASK); > >> + } > >> > >> if (intmask & SDHCI_INT_BUS_POWER) > >> pr_err("%s: Card is consuming too much power!\n", > >> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > >> index c055e24..5f8301e 100644 > >> --- a/drivers/mmc/host/sdhci.h > >> +++ b/drivers/mmc/host/sdhci.h > >> @@ -24,6 +24,8 @@ > >> * Controller registers > >> */ > >> > >> +#define SDHCI_QUIRK2_SLOW_INT_CLR (1<<5) > > > > IIRC, new quirk isn't allowed now. > > > > Why not? IIRC, mmc subsystem will behave as a lib in the long run, so the community and developers call for no new quirk. For your case, we may need to handle the udelay in sdhci-msm.c, export sdhci_irq as a helper function? Thanks -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html