MLK-17290-01 irqchip: imx-irqsteer: add runtime pm support

Add runtime pm to manage irqsteer clock and its power domain in system
idle and suspend status to save power.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Tested-by: Guoniu.Zhou <guoniu.zhou@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>

diff --git a/drivers/irqchip/irq-imx-irqsteer.c b/drivers/irqchip/irq-imx-irqsteer.c
index 6aa0a68..eec5308 100644 (file)
--- a/drivers/irqchip/irq-imx-irqsteer.c
+++ b/drivers/irqchip/irq-imx-irqsteer.c
@@ -15,6 +15,7 @@
 #include <linux/irqdomain.h>
 #include <linux/of_platform.h>
 #include <linux/spinlock.h>
+#include <linux/pm_runtime.h>
 
 #define CHANREG_OFF    (irqsteer_data->channum * 4)
 #define CHANCTRL       0x0
@@ -25,6 +26,7 @@
 #define CHAN_MASTRSTAT (CHAN_MINTDIS + 0x4)
 
 struct irqsteer_irqchip_data {
+       struct irq_chip chip;
        spinlock_t lock;
        struct platform_device  *pdev;
        void __iomem *regs;
@@ -34,6 +36,7 @@ struct irqsteer_irqchip_data {
        int endian;     /* 0: littel endian; 1: big endian */
        struct irq_domain *domain;
        int *saved_reg;
+       bool inited;
        unsigned int irqstat[];
 };
 
@@ -84,8 +87,10 @@ static struct irq_chip imx_irqsteer_irq_chip = {
 static int imx_irqsteer_irq_map(struct irq_domain *h, unsigned int irq,
                                irq_hw_number_t hwirq)
 {
+       struct irqsteer_irqchip_data *irqsteer_data = h->host_data;
+
        irq_set_chip_data(irq, h->host_data);
-       irq_set_chip_and_handler(irq, &imx_irqsteer_irq_chip, handle_level_irq);
+       irq_set_chip_and_handler(irq, &irqsteer_data->chip, handle_level_irq);
 
        return 0;
 }
@@ -99,6 +104,11 @@ static void imx_irqsteer_init(struct irqsteer_irqchip_data *irqsteer_data)
 {
        /* enable channel 1 in default */
        writel_relaxed(1, irqsteer_data->regs + CHANCTRL);
+
+       /* read back CHANCTRL register cannot reflact on HW register
+        * real value due to the HW action, so add one flag here.
+        */
+       irqsteer_data->inited = true;
 }
 
 static void imx_irqsteer_update_irqstat(struct irqsteer_irqchip_data *irqsteer_data)
@@ -174,6 +184,9 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
        if (!irqsteer_data->saved_reg)
                return -ENOMEM;
 
+       irqsteer_data->chip = imx_irqsteer_irq_chip;
+       irqsteer_data->chip.parent_device = &pdev->dev;
+
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        irqsteer_data->regs = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(irqsteer_data->regs)) {
@@ -197,16 +210,9 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
        irqsteer_data->channum = channum;
        irqsteer_data->endian  = endian;
        irqsteer_data->pdev = pdev;
+       irqsteer_data->inited = false;
        spin_lock_init(&irqsteer_data->lock);
 
-       ret = clk_prepare_enable(irqsteer_data->ipg_clk);
-       if (ret) {
-               dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
-               return ret;
-       }
-
-       imx_irqsteer_init(irqsteer_data);
-
        irqsteer_data->domain = irq_domain_add_linear(np,
                                                 irqsteer_data->channum * 32,
                                                 &imx_irqsteer_domain_ops,
@@ -223,6 +229,7 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, irqsteer_data);
 
+       pm_runtime_enable(&pdev->dev);
        return 0;
 }
 
@@ -234,10 +241,7 @@ static int imx_irqsteer_remove(struct platform_device *pdev)
 
        irq_domain_remove(irqsteer_data->domain);
 
-       platform_set_drvdata(pdev, NULL);
-       clk_disable_unprepare(irqsteer_data->ipg_clk);
-
-       return 0;
+       return pm_runtime_force_suspend(&pdev->dev);
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -259,17 +263,23 @@ static void imx_irqsteer_restore_regs(struct irqsteer_irqchip_data *data)
                writel_relaxed(data->saved_reg[num + 1], data->regs + CHANMASK(num));
 }
 
-static int imx_irqsteer_suspend(struct device *dev)
+static int imx_irqsteer_runtime_suspend(struct device *dev)
 {
        struct irqsteer_irqchip_data *irqsteer_data = dev_get_drvdata(dev);
 
+       /* After device's runtime suspended, device's power domain maybe off,
+        * if some sub_irqs resouces are not freed, it needs to save registers
+        * when device's suspend force runtime suspend. And even if all sub_irqs
+        * are freed, it also needs to save CHANCTRL register.
+        */
        imx_irqsteer_save_regs(irqsteer_data);
+
        clk_disable_unprepare(irqsteer_data->ipg_clk);
 
        return 0;
 }
 
-static int imx_irqsteer_resume(struct device *dev)
+static int imx_irqsteer_runtime_resume(struct device *dev)
 {
        struct irqsteer_irqchip_data *irqsteer_data = dev_get_drvdata(dev);
        int ret;
@@ -279,13 +289,21 @@ static int imx_irqsteer_resume(struct device *dev)
                dev_err(dev, "failed to enable ipg clk: %d\n", ret);
                return ret;
        }
-       imx_irqsteer_restore_regs(irqsteer_data);
+
+       /* don't need restore registers when first sub_irq requested */
+       if (!irqsteer_data->inited)
+               imx_irqsteer_init(irqsteer_data);
+       else
+               imx_irqsteer_restore_regs(irqsteer_data);
 
        return 0;
 }
 
 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_runtime_suspend,
+                          imx_irqsteer_runtime_resume, NULL)
 };
 #define IMX_IRQSTEER_PM      (&imx_irqsteer_pm_ops)
 #else