/*
* 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
* threshold 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;
dev_dbg(wm->dev, "Raw coordinates: x=%x, y=%x, p=%x\n",
x, y, p);
/* 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");
