irqchip/imx-irqsteer: Add runtime PM support

There are now SoCs that integrate the irqsteer controller within
a separate power domain. In order to allow this domain to be
powered down when not needed, add runtime PM support to the driver.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220406163701.1277930-2-l.stach@pengutronix.de

drivers/irqchip/irq-imx-irqsteer.c

@@ -12,6 +12,7 @@
 #include <linux/kernel.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
 #include <linux/spinlock.h>
 
 #define CTRL_STRIDE_OFF(_t, _r)	(_t * 4 * _r)
@@ -175,7 +176,7 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 	data->irq_count = DIV_ROUND_UP(irqs_num, 64);
 	data->reg_num = irqs_num / 32;
 
-	if (IS_ENABLED(CONFIG_PM_SLEEP)) {
+	if (IS_ENABLED(CONFIG_PM)) {
 		data->saved_reg = devm_kzalloc(&pdev->dev,
 					sizeof(u32) * data->reg_num,
 					GFP_KERNEL);
@@ -199,6 +200,7 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 		ret = -ENOMEM;
 		goto out;
 	}
+	irq_domain_set_pm_device(data->domain, &pdev->dev);
 
 	if (!data->irq_count || data->irq_count > CHAN_MAX_OUTPUT_INT) {
 		ret = -EINVAL;
@@ -219,6 +221,9 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, data);
 
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
 	return 0;
 out:
 	clk_disable_unprepare(data->ipg_clk);
@@ -241,7 +246,7 @@ static int imx_irqsteer_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
 static void imx_irqsteer_save_regs(struct irqsteer_data *data)
 {
 	int i;
@@ -288,7 +293,10 @@ static int imx_irqsteer_resume(struct device *dev)
 #endif
 
 static const struct dev_pm_ops imx_irqsteer_pm_ops = {
-	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_irqsteer_suspend, imx_irqsteer_resume)
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				      pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(imx_irqsteer_suspend,
+			   imx_irqsteer_resume, NULL)
 };
 
 static const struct of_device_id imx_irqsteer_dt_ids[] = {