Input: add accelerated touchscreen support for Marvell Zylonite
authorMark Brown <broonie@opensource.wolfsonmicro.com>
Wed, 4 Mar 2009 09:12:49 +0000 (01:12 -0800)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Sun, 8 Mar 2009 23:35:26 +0000 (16:35 -0700)
This patch implements accelerated touchscreen support for the Marvell
Zylonite development platform, supporting pen down interrupts and
continuous mode data transfers.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
drivers/input/touchscreen/Kconfig
drivers/input/touchscreen/Makefile
drivers/input/touchscreen/zylonite-wm97xx.c [new file with mode: 0644]

index bb6486a8c070f599430020681c395e9e59300eb9..a31d43494a8ddb29112d0e333d226eb3e7d128d0 100644 (file)
@@ -308,6 +308,19 @@ config TOUCHSCREEN_WM97XX_MAINSTONE
          To compile this driver as a module, choose M here: the
          module will be called mainstone-wm97xx.
 
+config TOUCHSCREEN_WM97XX_ZYLONITE
+       tristate "Zylonite accelerated touch"
+       depends on TOUCHSCREEN_WM97XX && MACH_ZYLONITE
+       select TOUCHSCREEN_WM9713
+       help
+         Say Y here for support for streaming mode with the touchscreen
+         on Zylonite systems.
+
+         If unsure, say N.
+
+         To compile this driver as a module, choose M here: the
+         module will be called zylonite-wm97xx.
+
 config TOUCHSCREEN_USB_COMPOSITE
        tristate "USB Touchscreen Driver"
        depends on USB_ARCH_HAS_HCD
index d3375aff46fe14303ed44f44e686213485aafb20..82dd918a4dec91c695e0da36db4c7362b8a01bae 100644 (file)
@@ -34,3 +34,4 @@ wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9705)        += wm9705.o
 wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9712) += wm9712.o
 wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9713) += wm9713.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE)     += mainstone-wm97xx.o
+obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE)      += zylonite-wm97xx.o
diff --git a/drivers/input/touchscreen/zylonite-wm97xx.c b/drivers/input/touchscreen/zylonite-wm97xx.c
new file mode 100644 (file)
index 0000000..41e4359
--- /dev/null
@@ -0,0 +1,240 @@
+/*
+ * zylonite-wm97xx.c  --  Zylonite Continuous Touch screen driver
+ *
+ * Copyright 2004, 2007, 2008 Wolfson Microelectronics PLC.
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ * Parts Copyright : Ian Molton <spyro@f2s.com>
+ *                   Andrew Zabolotny <zap@homelink.ru>
+ *
+ *  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;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ * Notes:
+ *     This is a wm97xx extended touch driver supporting interrupt driven
+ *     and continuous operation on Marvell Zylonite development systems
+ *     (which have a WM9713 on board).
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/wm97xx.h>
+
+#include <mach/hardware.h>
+#include <mach/mfp.h>
+#include <mach/regs-ac97.h>
+
+struct continuous {
+       u16 id;    /* codec id */
+       u8 code;   /* continuous code */
+       u8 reads;  /* number of coord reads per read cycle */
+       u32 speed; /* number of coords per second */
+};
+
+#define WM_READS(sp) ((sp / HZ) + 1)
+
+static const struct continuous cinfo[] = {
+       { WM9713_ID2, 0, WM_READS(94),  94  },
+       { WM9713_ID2, 1, WM_READS(120), 120 },
+       { WM9713_ID2, 2, WM_READS(154), 154 },
+       { WM9713_ID2, 3, WM_READS(188), 188 },
+};
+
+/* continuous speed index */
+static int sp_idx;
+
+/*
+ * Pen sampling frequency (Hz) in continuous mode.
+ */
+static int cont_rate = 200;
+module_param(cont_rate, int, 0);
+MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");
+
+/*
+ * Pressure readback.
+ *
+ * Set to 1 to read back pen down pressure
+ */
+static int pressure;
+module_param(pressure, int, 0);
+MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");
+
+/*
+ * AC97 touch data slot.
+ *
+ * Touch screen readback data ac97 slot
+ */
+static int ac97_touch_slot = 5;
+module_param(ac97_touch_slot, int, 0);
+MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");
+
+
+/* flush AC97 slot 5 FIFO machines */
+static void wm97xx_acc_pen_up(struct wm97xx *wm)
+{
+       int i;
+
+       msleep(1);
+
+       for (i = 0; i < 16; i++)
+               MODR;
+}
+
+static int wm97xx_acc_pen_down(struct wm97xx *wm)
+{
+       u16 x, y, p = 0x100 | WM97XX_ADCSEL_PRES;
+       int reads = 0;
+       static u16 last, tries;
+
+       /* When the AC97 queue has been drained we need to allow time
+        * to buffer up samples otherwise we end up spinning polling
+        * for samples.  The controller can't have a suitably low
+        * threashold set to use the notifications it gives.
+        */
+       msleep(1);
+
+       if (tries > 5) {
+               tries = 0;
+               return RC_PENUP;
+       }
+
+       x = MODR;
+       if (x == last) {
+               tries++;
+               return RC_AGAIN;
+       }
+       last = x;
+       do {
+               if (reads)
+                       x = MODR;
+               y = MODR;
+               if (pressure)
+                       p = MODR;
+
+               /* are samples valid */
+               if ((x & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_X ||
+                   (y & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_Y ||
+                   (p & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_PRES)
+                       goto up;
+
+               /* coordinate is good */
+               tries = 0;
+               input_report_abs(wm->input_dev, ABS_X, x & 0xfff);
+               input_report_abs(wm->input_dev, ABS_Y, y & 0xfff);
+               input_report_abs(wm->input_dev, ABS_PRESSURE, p & 0xfff);
+               input_report_key(wm->input_dev, BTN_TOUCH, (p != 0));
+               input_sync(wm->input_dev);
+               reads++;
+       } while (reads < cinfo[sp_idx].reads);
+up:
+       return RC_PENDOWN | RC_AGAIN;
+}
+
+static int wm97xx_acc_startup(struct wm97xx *wm)
+{
+       int idx;
+
+       /* check we have a codec */
+       if (wm->ac97 == NULL)
+               return -ENODEV;
+
+       /* Go you big red fire engine */
+       for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
+               if (wm->id != cinfo[idx].id)
+                       continue;
+               sp_idx = idx;
+               if (cont_rate <= cinfo[idx].speed)
+                       break;
+       }
+       wm->acc_rate = cinfo[sp_idx].code;
+       wm->acc_slot = ac97_touch_slot;
+       dev_info(wm->dev,
+                "zylonite accelerated touchscreen driver, %d samples/sec\n",
+                cinfo[sp_idx].speed);
+
+       return 0;
+}
+
+static void wm97xx_irq_enable(struct wm97xx *wm, int enable)
+{
+       if (enable)
+               enable_irq(wm->pen_irq);
+       else
+               disable_irq_nosync(wm->pen_irq);
+}
+
+static struct wm97xx_mach_ops zylonite_mach_ops = {
+       .acc_enabled    = 1,
+       .acc_pen_up     = wm97xx_acc_pen_up,
+       .acc_pen_down   = wm97xx_acc_pen_down,
+       .acc_startup    = wm97xx_acc_startup,
+       .irq_enable     = wm97xx_irq_enable,
+       .irq_gpio       = WM97XX_GPIO_2,
+};
+
+static int zylonite_wm97xx_probe(struct platform_device *pdev)
+{
+       struct wm97xx *wm = platform_get_drvdata(pdev);
+       int gpio_touch_irq;
+
+       if (cpu_is_pxa320())
+               gpio_touch_irq = mfp_to_gpio(MFP_PIN_GPIO15);
+       else
+               gpio_touch_irq = mfp_to_gpio(MFP_PIN_GPIO26);
+
+       wm->pen_irq = IRQ_GPIO(gpio_touch_irq);
+       set_irq_type(IRQ_GPIO(gpio_touch_irq), IRQ_TYPE_EDGE_BOTH);
+
+       wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
+                          WM97XX_GPIO_POL_HIGH,
+                          WM97XX_GPIO_STICKY,
+                          WM97XX_GPIO_WAKE);
+       wm97xx_config_gpio(wm, WM97XX_GPIO_2, WM97XX_GPIO_OUT,
+                          WM97XX_GPIO_POL_HIGH,
+                          WM97XX_GPIO_NOTSTICKY,
+                          WM97XX_GPIO_NOWAKE);
+
+       return wm97xx_register_mach_ops(wm, &zylonite_mach_ops);
+}
+
+static int zylonite_wm97xx_remove(struct platform_device *pdev)
+{
+       struct wm97xx *wm = platform_get_drvdata(pdev);
+
+       wm97xx_unregister_mach_ops(wm);
+
+       return 0;
+}
+
+static struct platform_driver zylonite_wm97xx_driver = {
+       .probe  = zylonite_wm97xx_probe,
+       .remove = zylonite_wm97xx_remove,
+       .driver = {
+               .name   = "wm97xx-touch",
+       },
+};
+
+static int __init zylonite_wm97xx_init(void)
+{
+       return platform_driver_register(&zylonite_wm97xx_driver);
+}
+
+static void __exit zylonite_wm97xx_exit(void)
+{
+       platform_driver_unregister(&zylonite_wm97xx_driver);
+}
+
+module_init(zylonite_wm97xx_init);
+module_exit(zylonite_wm97xx_exit);
+
+/* Module information */
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("wm97xx continuous touch driver for Zylonite");
+MODULE_LICENSE("GPL");