input: TSC: Add suspend/resume feature for TSC

This patch adds support for suspend/resume feature in
touchscreen.
Since touchscreen is in wakeup domain, it can be used
to resume the system.

Signed-off-by: Patil, Rachna <rachna@ti.com>

diff --git a/drivers/input/touchscreen/ti_tscadc.c b/drivers/input/touchscreen/ti_tscadc.c
index e3b57755936c2b032a772ad3aa4b074285b6c6ba..9b34b82072799945e61b2a2cdc2bf6e6b1a33d52 100644 (file)
--- a/drivers/input/touchscreen/ti_tscadc.c
+++ b/drivers/input/touchscreen/ti_tscadc.c
@@ -26,11 +26,13 @@
 #include <linux/io.h>
 #include <linux/input/ti_tscadc.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 
 #define TSCADC_REG_IRQEOI              0x020
 #define TSCADC_REG_RAWIRQSTATUS                0x024
 #define TSCADC_REG_IRQSTATUS           0x028
 #define TSCADC_REG_IRQENABLE           0x02C
+#define TSCADC_REG_IRQCLR              0x030
 #define TSCADC_REG_IRQWAKEUP           0x034
 #define TSCADC_REG_CTRL                        0x040
 #define TSCADC_REG_ADCFSM              0x044
@@ -54,10 +56,12 @@
 
 /*     Register Bitfields      */
 #define TSCADC_IRQWKUP_ENB             BIT(0)
+#define TSCADC_IRQWKUP_DISABLE         0x00
 #define TSCADC_STPENB_STEPENB          0x7FFF
 #define TSCADC_IRQENB_FIFO0THRES       BIT(2)
 #define TSCADC_IRQENB_FIFO1THRES       BIT(5)
 #define TSCADC_IRQENB_PENUP            BIT(9)
+#define TSCADC_IRQENB_HW_PEN           BIT(0)
 #define TSCADC_STEPCONFIG_MODE_HWSYNC  0x2
 #define TSCADC_STEPCONFIG_2SAMPLES_AVG (1 << 4)
 #define TSCADC_STEPCONFIG_XPP          BIT(5)
@@ -104,9 +108,9 @@ struct tscadc {
        int                     wires;
        int                     analog_input;
        int                     x_plate_resistance;
-       struct clk              *tsc_ick;
        int                     irq;
        void __iomem            *tsc_base;
+       unsigned int            ctrl;
 };
 
 static unsigned int tscadc_readl(struct tscadc *ts, unsigned int reg)
@@ -356,6 +360,7 @@ static irqreturn_t tscadc_interrupt(int irq, void *dev)
                }
                irqclr |= TSCADC_IRQENB_PENUP;
        }
+       irqclr |= TSCADC_IRQENB_HW_PEN;
 
        tscadc_writel(ts_dev, TSCADC_REG_IRQSTATUS, irqclr);
 
@@ -429,12 +434,8 @@ static     int __devinit tscadc_probe(struct platform_device *pdev)
                goto err_unmap_regs;
        }
 
-       ts_dev->tsc_ick = clk_get(&pdev->dev, "adc_tsc_ick");
-       if (IS_ERR(ts_dev->tsc_ick)) {
-               dev_err(&pdev->dev, "failed to get TSC ick\n");
-               goto err_free_irq;
-       }
-       clk_enable(ts_dev->tsc_ick);
+       pm_runtime_enable(&pdev->dev);
+       pm_runtime_get_sync(&pdev->dev);
 
        clk = clk_get(&pdev->dev, "adc_tsc_fck");
        if (IS_ERR(clk)) {
@@ -452,9 +453,6 @@ static      int __devinit tscadc_probe(struct platform_device *pdev)
        clk_value = clk_value - 1;
        tscadc_writel(ts_dev, TSCADC_REG_CLKDIV, clk_value);
 
-        /* Enable wake-up of the SoC using touchscreen */
-       tscadc_writel(ts_dev, TSCADC_REG_IRQWAKEUP, TSCADC_IRQWKUP_ENB);
-
        ts_dev->wires = pdata->wires;
        ts_dev->analog_input = pdata->analog_input;
        ts_dev->x_plate_resistance = pdata->x_plate_resistance;
@@ -475,6 +473,7 @@ static      int __devinit tscadc_probe(struct platform_device *pdev)
                break;
        }
        tscadc_writel(ts_dev, TSCADC_REG_CTRL, ctrl);
+       ts_dev->ctrl = ctrl;
 
        /* Set register bits for Idel Config Mode */
        tsc_idle_config(ts_dev);
@@ -505,12 +504,12 @@ static    int __devinit tscadc_probe(struct platform_device *pdev)
        if (err)
                goto err_fail;
 
+       device_init_wakeup(&pdev->dev, true);
        platform_set_drvdata(pdev, ts_dev);
        return 0;
 
 err_fail:
-       clk_disable(ts_dev->tsc_ick);
-       clk_put(ts_dev->tsc_ick);
+       pm_runtime_disable(&pdev->dev);
 err_free_irq:
        free_irq(ts_dev->irq, ts_dev);
 err_unmap_regs:
@@ -536,11 +535,11 @@ static int __devexit tscadc_remove(struct platform_device *pdev)
        iounmap(ts_dev->tsc_base);
        release_mem_region(res->start, resource_size(res));
 
-       clk_disable(ts_dev->tsc_ick);
-       clk_put(ts_dev->tsc_ick);
+       pm_runtime_disable(&pdev->dev);
 
        kfree(ts_dev);
 
+       device_init_wakeup(&pdev->dev, 0);
        platform_set_drvdata(pdev, NULL);
        return 0;
 }
@@ -548,14 +547,22 @@ static int __devexit tscadc_remove(struct platform_device *pdev)
 static int tscadc_suspend(struct platform_device *pdev, pm_message_t state)
 {
        struct tscadc *ts_dev = platform_get_drvdata(pdev);
-       unsigned int  status;
+       unsigned int idle;
+
+       if (device_may_wakeup(&pdev->dev)) {
+               idle = tscadc_readl(ts_dev, TSCADC_REG_IRQENABLE);
+               tscadc_writel(ts_dev, TSCADC_REG_IRQENABLE,
+                               (idle | TSCADC_IRQENB_HW_PEN));
+               tscadc_writel(ts_dev, TSCADC_REG_IRQWAKEUP, TSCADC_IRQWKUP_ENB);
+       }
 
-       status = tscadc_readl(ts_dev, TSCADC_REG_CTRL);
-       status &= ~(TSCADC_CNTRLREG_TSCSSENB);
-       tscadc_writel(ts_dev, TSCADC_REG_CTRL, status);
+       /* module disable */
+       idle = 0;
+       idle = tscadc_readl(ts_dev, TSCADC_REG_CTRL);
+       idle &= ~(TSCADC_CNTRLREG_TSCSSENB);
+       tscadc_writel(ts_dev, TSCADC_REG_CTRL, idle);
 
-       clk_disable(ts_dev->tsc_ick);
-       clk_put(ts_dev->tsc_ick);
+       pm_runtime_put_sync(&pdev->dev);
 
        return 0;
 
@@ -564,13 +571,24 @@ static int tscadc_suspend(struct platform_device *pdev, pm_message_t state)
 static int tscadc_resume(struct platform_device *pdev)
 {
        struct tscadc *ts_dev = platform_get_drvdata(pdev);
-       unsigned int  status;
+       unsigned int restore;
 
-       clk_enable(ts_dev->tsc_ick);
+       pm_runtime_get_sync(&pdev->dev);
 
-       status = tscadc_readl(ts_dev, TSCADC_REG_CTRL);
+       if (device_may_wakeup(&pdev->dev)) {
+               tscadc_writel(ts_dev, TSCADC_REG_IRQWAKEUP,
+                               TSCADC_IRQWKUP_DISABLE);
+               tscadc_writel(ts_dev, TSCADC_REG_IRQCLR, TSCADC_IRQENB_HW_PEN);
+       }
+
+       /* context restore */
+       tscadc_writel(ts_dev, TSCADC_REG_CTRL, ts_dev->ctrl);
+       tsc_idle_config(ts_dev);
+       tsc_step_config(ts_dev);
+       tscadc_writel(ts_dev, TSCADC_REG_FIFO1THR, 6);
+       restore = tscadc_readl(ts_dev, TSCADC_REG_CTRL);
        tscadc_writel(ts_dev, TSCADC_REG_CTRL,
-                       (status | TSCADC_CNTRLREG_TSCSSENB));
+                       (restore | TSCADC_CNTRLREG_TSCSSENB));
 
        return 0;
 }