Input: add support for touchscreen on W90P910 ARM platform
Wan ZongShun [Thu, 11 Jun 2009 06:27:22 +0000 (23:27 -0700)]
The touchscreen works in two modes, wait trigger mode and auto-semi
mode. The device starts in wait trigger mode and waits until pressure
is detected, then device sets WT_INT bit and raises an interrupt.
The driver should put the device into auto-semi mode and prepare for
reading first X and then Y coordinates. When coordinate data is ready
the driver sets ADC_INT bit and raises interrupt again.

[dtor@mail.ru: various cleanups]
Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/Kconfig
drivers/input/touchscreen/Makefile
drivers/input/touchscreen/w90p910_ts.c [new file with mode: 0644]

index 1b4a167..72e2712 100644 (file)
@@ -490,4 +490,12 @@ config TOUCHSCREEN_TSC2007
          To compile this driver as a module, choose M here: the
          module will be called tsc2007.
 
+config TOUCHSCREEN_W90X900
+       tristate "W90P910 touchscreen driver"
+       help
+         Say Y here if you have a W90P910 based touchscreen.
+
+         To compile this driver as a module, choose M here: the
+         module will be called w90p910_ts.
+
 endif
index 10e0be6..3e1c5e0 100644 (file)
@@ -39,3 +39,4 @@ wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9713)        += wm9713.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_ATMEL) += atmel-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE)     += mainstone-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE)      += zylonite-wm97xx.o
+obj-$(CONFIG_TOUCHSCREEN_W90X900)      += w90p910_ts.o
diff --git a/drivers/input/touchscreen/w90p910_ts.c b/drivers/input/touchscreen/w90p910_ts.c
new file mode 100644 (file)
index 0000000..6071f58
--- /dev/null
@@ -0,0 +1,350 @@
+/*
+ * Copyright (c) 2008 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+
+/* ADC controller bit defines */
+#define ADC_DELAY      0xf00
+#define ADC_DOWN       0x01
+#define ADC_TSC_Y      (0x01 << 8)
+#define ADC_TSC_X      (0x00 << 8)
+#define TSC_FOURWIRE   (~(0x03 << 1))
+#define ADC_CLK_EN     (0x01 << 28)    /* ADC clock enable */
+#define ADC_READ_CON   (0x01 << 12)
+#define ADC_CONV       (0x01 << 13)
+#define ADC_SEMIAUTO   (0x01 << 14)
+#define ADC_WAITTRIG   (0x03 << 14)
+#define ADC_RST1       (0x01 << 16)
+#define ADC_RST0       (0x00 << 16)
+#define ADC_EN         (0x01 << 17)
+#define ADC_INT                (0x01 << 18)
+#define WT_INT         (0x01 << 20)
+#define ADC_INT_EN     (0x01 << 21)
+#define LVD_INT_EN     (0x01 << 22)
+#define WT_INT_EN      (0x01 << 23)
+#define ADC_DIV                (0x04 << 1)     /* div = 6 */
+
+enum ts_state {
+       TS_WAIT_NEW_PACKET,     /* We are waiting next touch report */
+       TS_WAIT_X_COORD,        /* We are waiting for ADC to report X coord */
+       TS_WAIT_Y_COORD,        /* We are waiting for ADC to report Y coord */
+       TS_IDLE,                /* Input device is closed, don't do anything */
+};
+
+struct w90p910_ts {
+       struct input_dev *input;
+       struct timer_list timer;
+       int irq_num;
+       void __iomem *clocken;
+       void __iomem *ts_reg;
+       spinlock_t lock;
+       enum ts_state state;
+};
+
+static void w90p910_report_event(struct w90p910_ts *w90p910_ts, bool down)
+{
+       struct input_dev *dev = w90p910_ts->input;
+
+       if (down) {
+               input_report_abs(dev, ABS_X,
+                                __raw_readl(w90p910_ts->ts_reg + 0x0c));
+               input_report_abs(dev, ABS_Y,
+                                __raw_readl(w90p910_ts->ts_reg + 0x10));
+       }
+
+       input_report_key(dev, BTN_TOUCH, down);
+       input_sync(dev);
+}
+
+static void w90p910_prepare_x_reading(struct w90p910_ts *w90p910_ts)
+{
+       unsigned long ctlreg;
+
+       __raw_writel(ADC_TSC_X, w90p910_ts->ts_reg + 0x04);
+       ctlreg = __raw_readl(w90p910_ts->ts_reg);
+       ctlreg &= ~(ADC_WAITTRIG | WT_INT | WT_INT_EN);
+       ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
+       __raw_writel(ctlreg, w90p910_ts->ts_reg);
+
+       w90p910_ts->state = TS_WAIT_X_COORD;
+}
+
+static void w90p910_prepare_y_reading(struct w90p910_ts *w90p910_ts)
+{
+       unsigned long ctlreg;
+
+       __raw_writel(ADC_TSC_Y, w90p910_ts->ts_reg + 0x04);
+       ctlreg = __raw_readl(w90p910_ts->ts_reg);
+       ctlreg &= ~(ADC_WAITTRIG | ADC_INT | WT_INT_EN);
+       ctlreg |= ADC_SEMIAUTO | ADC_INT_EN | ADC_CONV;
+       __raw_writel(ctlreg, w90p910_ts->ts_reg);
+
+       w90p910_ts->state = TS_WAIT_Y_COORD;
+}
+
+static void w90p910_prepare_next_packet(struct w90p910_ts *w90p910_ts)
+{
+       unsigned long ctlreg;
+
+       ctlreg = __raw_readl(w90p910_ts->ts_reg);
+       ctlreg &= ~(ADC_INT | ADC_INT_EN | ADC_SEMIAUTO | ADC_CONV);
+       ctlreg |= ADC_WAITTRIG | WT_INT_EN;
+       __raw_writel(ctlreg, w90p910_ts->ts_reg);
+
+       w90p910_ts->state = TS_WAIT_NEW_PACKET;
+}
+
+static irqreturn_t w90p910_ts_interrupt(int irq, void *dev_id)
+{
+       struct w90p910_ts *w90p910_ts = dev_id;
+       unsigned long flags;
+
+       spin_lock_irqsave(&w90p910_ts->lock, flags);
+
+       switch (w90p910_ts->state) {
+       case TS_WAIT_NEW_PACKET:
+               /*
+                * The controller only generates interrupts when pen
+                * is down.
+                */
+               del_timer(&w90p910_ts->timer);
+               w90p910_prepare_x_reading(w90p910_ts);
+               break;
+
+
+       case TS_WAIT_X_COORD:
+               w90p910_prepare_y_reading(w90p910_ts);
+               break;
+
+       case TS_WAIT_Y_COORD:
+               w90p910_report_event(w90p910_ts, true);
+               w90p910_prepare_next_packet(w90p910_ts);
+               mod_timer(&w90p910_ts->timer, jiffies + msecs_to_jiffies(100));
+               break;
+
+       case TS_IDLE:
+               break;
+       }
+
+       spin_unlock_irqrestore(&w90p910_ts->lock, flags);
+
+       return IRQ_HANDLED;
+}
+
+static void w90p910_check_pen_up(unsigned long data)
+{
+       struct w90p910_ts *w90p910_ts = (struct w90p910_ts *) data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&w90p910_ts->lock, flags);
+
+       if (w90p910_ts->state == TS_WAIT_NEW_PACKET &&
+           !(__raw_readl(w90p910_ts->ts_reg + 0x04) & ADC_DOWN)) {
+
+               w90p910_report_event(w90p910_ts, false);
+       }
+
+       spin_unlock_irqrestore(&w90p910_ts->lock, flags);
+}
+
+static int w90p910_open(struct input_dev *dev)
+{
+       struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
+       unsigned long val;
+
+       /* enable the ADC clock */
+       val = __raw_readl(w90p910_ts->clocken);
+       __raw_writel(val | ADC_CLK_EN, w90p910_ts->clocken);
+
+       __raw_writel(ADC_RST1, w90p910_ts->ts_reg);
+       msleep(1);
+       __raw_writel(ADC_RST0, w90p910_ts->ts_reg);
+       msleep(1);
+
+       /* set delay and screen type */
+       val = __raw_readl(w90p910_ts->ts_reg + 0x04);
+       __raw_writel(val & TSC_FOURWIRE, w90p910_ts->ts_reg + 0x04);
+       __raw_writel(ADC_DELAY, w90p910_ts->ts_reg + 0x08);
+
+       w90p910_ts->state = TS_WAIT_NEW_PACKET;
+       wmb();
+
+       /* set trigger mode */
+       val = __raw_readl(w90p910_ts->ts_reg);
+       val |= ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN;
+       __raw_writel(val, w90p910_ts->ts_reg);
+
+       return 0;
+}
+
+static void w90p910_close(struct input_dev *dev)
+{
+       struct w90p910_ts *w90p910_ts = input_get_drvdata(dev);
+       unsigned long val;
+
+       /* disable trigger mode */
+
+       spin_lock_irq(&w90p910_ts->lock);
+
+       w90p910_ts->state = TS_IDLE;
+
+       val = __raw_readl(w90p910_ts->ts_reg);
+       val &= ~(ADC_WAITTRIG | ADC_DIV | ADC_EN | WT_INT_EN | ADC_INT_EN);
+       __raw_writel(val, w90p910_ts->ts_reg);
+
+       spin_unlock_irq(&w90p910_ts->lock);
+
+       /* Now that interrupts are shut off we can safely delete timer */
+       del_timer_sync(&w90p910_ts->timer);
+
+       /* stop the ADC clock */
+       val = __raw_readl(w90p910_ts->clocken);
+       __raw_writel(val & ~ADC_CLK_EN, w90p910_ts->clocken);
+}
+
+static int __devinit w90x900ts_probe(struct platform_device *pdev)
+{
+       struct w90p910_ts *w90p910_ts;
+       struct input_dev *input_dev;
+       struct resource *res;
+       int err;
+
+       w90p910_ts = kzalloc(sizeof(struct w90p910_ts), GFP_KERNEL);
+       input_dev = input_allocate_device();
+       if (!w90p910_ts || !input_dev) {
+               err = -ENOMEM;
+               goto fail1;
+       }
+
+       w90p910_ts->input = input_dev;
+       w90p910_ts->state = TS_IDLE;
+       spin_lock_init(&w90p910_ts->lock);
+       setup_timer(&w90p910_ts->timer, w90p910_check_pen_up,
+                   (unsigned long)&w90p910_ts);
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res) {
+               err = -ENXIO;
+               goto fail1;
+       }
+
+       if (!request_mem_region(res->start, res->end - res->start + 1,
+                               pdev->name)) {
+               err = -EBUSY;
+               goto fail1;
+       }
+
+       w90p910_ts->ts_reg = ioremap(res->start, res->end - res->start + 1);
+       if (!w90p910_ts->ts_reg) {
+               err = -ENOMEM;
+               goto fail2;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+       if (!res) {
+               err = -ENXIO;
+               goto fail3;
+       }
+
+       w90p910_ts->clocken = (void __iomem *)res->start;
+
+       input_dev->name = "W90P910 TouchScreen";
+       input_dev->phys = "w90p910ts/event0";
+       input_dev->id.bustype = BUS_HOST;
+       input_dev->id.vendor  = 0x0005;
+       input_dev->id.product = 0x0001;
+       input_dev->id.version = 0x0100;
+       input_dev->dev.parent = &pdev->dev;
+       input_dev->open = w90p910_open;
+       input_dev->close = w90p910_close;
+
+       input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+       input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+       input_set_abs_params(input_dev, ABS_X, 0, 0x400, 0, 0);
+       input_set_abs_params(input_dev, ABS_Y, 0, 0x400, 0, 0);
+
+       input_set_drvdata(input_dev, w90p910_ts);
+
+       w90p910_ts->irq_num = platform_get_irq(pdev, 0);
+       if (request_irq(w90p910_ts->irq_num, w90p910_ts_interrupt,
+                       IRQF_DISABLED, "w90p910ts", w90p910_ts)) {
+               err = -EBUSY;
+               goto fail3;
+       }
+
+       err = input_register_device(w90p910_ts->input);
+       if (err)
+               goto fail4;
+
+       platform_set_drvdata(pdev, w90p910_ts);
+
+       return 0;
+
+fail4: free_irq(w90p910_ts->irq_num, w90p910_ts);
+fail3: iounmap(w90p910_ts->ts_reg);
+fail2: release_mem_region(res->start, res->end - res->start + 1);
+fail1: input_free_device(input_dev);
+       kfree(w90p910_ts);
+       return err;
+}
+
+static int __devexit w90x900ts_remove(struct platform_device *pdev)
+{
+       struct w90p910_ts *w90p910_ts = platform_get_drvdata(pdev);
+       struct resource *res;
+
+       free_irq(w90p910_ts->irq_num, w90p910_ts);
+       del_timer_sync(&w90p910_ts->timer);
+       iounmap(w90p910_ts->ts_reg);
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       release_mem_region(res->start, res->end - res->start + 1);
+
+       input_unregister_device(w90p910_ts->input);
+       kfree(w90p910_ts);
+
+       platform_set_drvdata(pdev, NULL);
+
+       return 0;
+}
+
+static struct platform_driver w90x900ts_driver = {
+       .probe          = w90x900ts_probe,
+       .remove         = __devexit_p(w90x900ts_remove),
+       .driver         = {
+               .name   = "w90x900-ts",
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init w90x900ts_init(void)
+{
+       return platform_driver_register(&w90x900ts_driver);
+}
+
+static void __exit w90x900ts_exit(void)
+{
+       platform_driver_unregister(&w90x900ts_driver);
+}
+
+module_init(w90x900ts_init);
+module_exit(w90x900ts_exit);
+
+MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
+MODULE_DESCRIPTION("w90p910 touch screen driver!");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:w90p910-ts");