mmc: sdhci-msm: fix issue with power irq


[ Upstream commit c7ccee224d2d551f712752c4a16947f6529d6506 ]

SDCC controller reset (SW_RST) during probe may trigger power irq if
previous status of PWRCTL was either BUS_ON or IO_HIGH_V. So before we
enable the power irq interrupt in GIC (by registering the interrupt
handler), we need to ensure that any pending power irq interrupt status
is acknowledged otherwise power irq interrupt handler would be fired
prematurely.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Vijay Viswanath <vviswana@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 90ed2e1..80c89a3 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -642,6 +642,21 @@
 			       CORE_VENDOR_SPEC_CAPABILITIES0);
 	}
 
+	/*
+	 * Power on reset state may trigger power irq if previous status of
+	 * PWRCTL was either BUS_ON or IO_HIGH_V. So before enabling pwr irq
+	 * interrupt in GIC, any pending power irq interrupt should be
+	 * acknowledged. Otherwise power irq interrupt handler would be
+	 * fired prematurely.
+	 */
+	sdhci_msm_voltage_switch(host);
+
+	/*
+	 * Ensure that above writes are propogated before interrupt enablement
+	 * in GIC.
+	 */
+	mb();
+
 	/* 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) {
@@ -651,6 +666,9 @@
 		goto clk_disable;
 	}
 
+	/* Enable pwr irq interrupts */
+	writel_relaxed(INT_MASK, msm_host->core_mem + CORE_PWRCTL_MASK);
+
 	ret = devm_request_threaded_irq(&pdev->dev, msm_host->pwr_irq, NULL,
 					sdhci_msm_pwr_irq, IRQF_ONESHOT,
 					dev_name(&pdev->dev), host);