On apq8016, apq8084 and apq8074 platforms, writing to the software reset register triggers the "power irq". We need to ack and handle the irq, otherwise the following message appears:
mmc0: Reset 0x1 never completed. sdhci: =========== REGISTER DUMP (mmc0)=========== sdhci: Sys addr: 0x00000000 | Version: 0x00002e02 sdhci: Blk size: 0x00004000 | Blk cnt: 0x00000000 sdhci: Argument: 0x00000000 | Trn mode: 0x00000000 sdhci: Present: 0x01f80000 | Host ctl: 0x00000000 sdhci: Power: 0x00000000 | Blk gap: 0x00000000 sdhci: Wake-up: 0x00000000 | Clock: 0x00000003 sdhci: Timeout: 0x00000000 | Int stat: 0x00000000 sdhci: Int enab: 0x00000000 | Sig enab: 0x00000000 sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000 sdhci: Caps: 0x322dc8b2 | Caps_1: 0x00008007 sdhci: Cmd: 0x00000000 | Max curr: 0x00000000 sdhci: Host ctl2: 0x00000000 sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x0000000000000000 sdhci: =========================================== Fix it by implementing the custom sdhci_reset() function, which performs the software reset and then handles the irq. Signed-off-by: Georgi Djakov <georgi.dja...@linaro.org> --- Changes since v1: (https://lkml.org/lkml/2016/11/22/411) * Perform the software reset by just writing to the SDHCI_SOFTWARE_RESET register and then check for the irq. drivers/mmc/host/sdhci-msm.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index 32879b845b75..157ae07f9309 100644 --- a/drivers/mmc/host/sdhci-msm.c +++ b/drivers/mmc/host/sdhci-msm.c @@ -1019,6 +1019,33 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock) __sdhci_msm_set_clock(host, clock); } +void sdhci_msm_reset(struct sdhci_host *host, u8 mask) +{ + unsigned long timeout = 100; + + sdhci_writeb(host, mask, SDHCI_SOFTWARE_RESET); + + if (mask & SDHCI_RESET_ALL) { + host->clock = 0; + + /* + * SDHCI_RESET_ALL triggers the PWR IRQ and we need + * to handle it here. + */ + sdhci_msm_voltage_switch(host); + } + + while (sdhci_readb(host, SDHCI_SOFTWARE_RESET) & mask) { + if (timeout == 0) { + pr_err("%s: Reset 0x%x never completed.\n", + mmc_hostname(host->mmc), (int)mask); + return; + } + timeout--; + mdelay(1); + } +} + static const struct of_device_id sdhci_msm_dt_match[] = { { .compatible = "qcom,sdhci-msm-v4" }, {}, @@ -1028,7 +1055,7 @@ MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match); static const struct sdhci_ops sdhci_msm_ops = { .platform_execute_tuning = sdhci_msm_execute_tuning, - .reset = sdhci_reset, + .reset = sdhci_msm_reset, .set_clock = sdhci_msm_set_clock, .get_min_clock = sdhci_msm_get_min_clock, .get_max_clock = sdhci_msm_get_max_clock,
