[PATCH 4.14 29/75] mmc: sdhci-msm: fix issue with power irq - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org,
	Subhash Jadavani <subhashj@codeaurora.org>,
	Vijay Viswanath <vviswana@codeaurora.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	Sasha Levin <alexander.levin@verizon.com>
Subject: [PATCH 4.14 29/75] mmc: sdhci-msm: fix issue with power irq
Date: Thu,  7 Dec 2017 14:07:51 +0100	[thread overview]
Message-ID: <20171207130819.942800523@linuxfoundation.org> (raw)
In-Reply-To: <20171207130818.742746317@linuxfoundation.org>

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Subhash Jadavani <subhashj@codeaurora.org>


[ 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>
---
 drivers/mmc/host/sdhci-msm.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -1251,6 +1251,21 @@ static int sdhci_msm_probe(struct platfo
 			       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) {
@@ -1260,6 +1275,9 @@ static int sdhci_msm_probe(struct platfo
 		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);
