Input: tegra-kbc - fix wakeup from suspend
authorRakesh Iyer <riyer@nvidia.com>
Thu, 8 Sep 2011 22:34:11 +0000 (15:34 -0700)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Fri, 9 Sep 2011 16:25:42 +0000 (09:25 -0700)
For wakeup to be reliable, kbc needs to be in interrupt mode before suspend.
Created common routine to control the FIFO interrupt.
Added synchronization to ensure orderly suspend.

Signed-off-by: Rakesh Iyer <riyer@nvidia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
drivers/input/keyboard/tegra-kbc.c

index a5a77915c65003fb30eb058765945353f11d6298..8fb474f0394001ed00df595355021d1e6ae73965 100644 (file)
@@ -55,6 +55,7 @@
 
 #define KBC_ROW_CFG0_0 0x8
 #define KBC_COL_CFG0_0 0x18
+#define KBC_TO_CNT_0   0x24
 #define KBC_INIT_DLY_0 0x28
 #define KBC_RPT_DLY_0  0x2c
 #define KBC_KP_ENT0_0  0x30
@@ -70,6 +71,7 @@ struct tegra_kbc {
        spinlock_t lock;
        unsigned int repoll_dly;
        unsigned long cp_dly_jiffies;
+       unsigned int cp_to_wkup_dly;
        bool use_fn_map;
        bool use_ghost_filter;
        const struct tegra_kbc_platform_data *pdata;
@@ -341,6 +343,18 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
        kbc->num_pressed_keys = num_down;
 }
 
+static void tegra_kbc_set_fifo_interrupt(struct tegra_kbc *kbc, bool enable)
+{
+       u32 val;
+
+       val = readl(kbc->mmio + KBC_CONTROL_0);
+       if (enable)
+               val |= KBC_CONTROL_FIFO_CNT_INT_EN;
+       else
+               val &= ~KBC_CONTROL_FIFO_CNT_INT_EN;
+       writel(val, kbc->mmio + KBC_CONTROL_0);
+}
+
 static void tegra_kbc_keypress_timer(unsigned long data)
 {
        struct tegra_kbc *kbc = (struct tegra_kbc *)data;
@@ -370,9 +384,7 @@ static void tegra_kbc_keypress_timer(unsigned long data)
 
                /* All keys are released so enable the keypress interrupt */
                spin_lock_irqsave(&kbc->lock, flags);
-               val = readl(kbc->mmio + KBC_CONTROL_0);
-               val |= KBC_CONTROL_FIFO_CNT_INT_EN;
-               writel(val, kbc->mmio + KBC_CONTROL_0);
+               tegra_kbc_set_fifo_interrupt(kbc, true);
                spin_unlock_irqrestore(&kbc->lock, flags);
        }
 }
@@ -380,15 +392,13 @@ static void tegra_kbc_keypress_timer(unsigned long data)
 static irqreturn_t tegra_kbc_isr(int irq, void *args)
 {
        struct tegra_kbc *kbc = args;
-       u32 val, ctl;
+       u32 val;
 
        /*
         * Until all keys are released, defer further processing to
         * the polling loop in tegra_kbc_keypress_timer
         */
-       ctl = readl(kbc->mmio + KBC_CONTROL_0);
-       ctl &= ~KBC_CONTROL_FIFO_CNT_INT_EN;
-       writel(ctl, kbc->mmio + KBC_CONTROL_0);
+       tegra_kbc_set_fifo_interrupt(kbc, false);
 
        /*
         * Quickly bail out & reenable interrupts if the fifo threshold
@@ -404,8 +414,7 @@ static irqreturn_t tegra_kbc_isr(int irq, void *args)
                 */
                mod_timer(&kbc->timer, jiffies + kbc->cp_dly_jiffies);
        } else {
-               ctl |= KBC_CONTROL_FIFO_CNT_INT_EN;
-               writel(ctl, kbc->mmio + KBC_CONTROL_0);
+               tegra_kbc_set_fifo_interrupt(kbc, true);
        }
 
        return IRQ_HANDLED;
@@ -734,18 +743,30 @@ static int tegra_kbc_suspend(struct device *dev)
        struct platform_device *pdev = to_platform_device(dev);
        struct tegra_kbc *kbc = platform_get_drvdata(pdev);
 
+       mutex_lock(&kbc->idev->mutex);
        if (device_may_wakeup(&pdev->dev)) {
-               tegra_kbc_setup_wakekeys(kbc, true);
-               enable_irq_wake(kbc->irq);
+               disable_irq(kbc->irq);
+               del_timer_sync(&kbc->timer);
+               tegra_kbc_set_fifo_interrupt(kbc, false);
+
                /* Forcefully clear the interrupt status */
                writel(0x7, kbc->mmio + KBC_INT_0);
+               /*
+                * Store the previous resident time of continuous polling mode.
+                * Force the keyboard into interrupt mode.
+                */
+               kbc->cp_to_wkup_dly = readl(kbc->mmio + KBC_TO_CNT_0);
+               writel(0, kbc->mmio + KBC_TO_CNT_0);
+
+               tegra_kbc_setup_wakekeys(kbc, true);
                msleep(30);
+
+               enable_irq_wake(kbc->irq);
        } else {
-               mutex_lock(&kbc->idev->mutex);
                if (kbc->idev->users)
                        tegra_kbc_stop(kbc);
-               mutex_unlock(&kbc->idev->mutex);
        }
+       mutex_unlock(&kbc->idev->mutex);
 
        return 0;
 }
@@ -756,15 +777,22 @@ static int tegra_kbc_resume(struct device *dev)
        struct tegra_kbc *kbc = platform_get_drvdata(pdev);
        int err = 0;
 
+       mutex_lock(&kbc->idev->mutex);
        if (device_may_wakeup(&pdev->dev)) {
                disable_irq_wake(kbc->irq);
                tegra_kbc_setup_wakekeys(kbc, false);
+
+               /* Restore the resident time of continuous polling mode. */
+               writel(kbc->cp_to_wkup_dly, kbc->mmio + KBC_TO_CNT_0);
+
+               tegra_kbc_set_fifo_interrupt(kbc, true);
+
+               enable_irq(kbc->irq);
        } else {
-               mutex_lock(&kbc->idev->mutex);
                if (kbc->idev->users)
                        err = tegra_kbc_start(kbc);
-               mutex_unlock(&kbc->idev->mutex);
        }
+       mutex_unlock(&kbc->idev->mutex);
 
        return err;
 }