slimbus: qcom-ngd-ctrl: check for device runtime PM status during ISR

Slimbus core interrupt is getting fired after suspend. At this point
ADSP slimbus hardware is off with gated clocks which is leading to an
unclocked access when HLOS slimbus tried to read the interrupt
status register in the ISR.
Co-developed-by: NChandana Kishori Chiluveru <cchiluve@codeaurora.org>
Signed-off-by: NChandana Kishori Chiluveru <cchiluve@codeaurora.org>
Signed-off-by: NKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20221118065246.6835-2-srinivas.kandagatla@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/slimbus/qcom-ngd-ctrl.c

@@ -763,7 +763,14 @@ static irqreturn_t qcom_slim_ngd_interrupt(int irq, void *d)
 {
 	struct qcom_slim_ngd_ctrl *ctrl = d;
 	void __iomem *base = ctrl->ngd->base;
-	u32 stat = readl(base + NGD_INT_STAT);
+	u32 stat;
+
+	if (pm_runtime_suspended(ctrl->ctrl.dev)) {
+		dev_warn_once(ctrl->dev, "Interrupt received while suspended\n");
+		return IRQ_NONE;
+	}
+
+	stat = readl(base + NGD_INT_STAT);
 
 	if ((stat & NGD_INT_MSG_BUF_CONTE) ||
 		(stat & NGD_INT_MSG_TX_INVAL) || (stat & NGD_INT_DEV_ERR) ||