Input: wm831x - add driver for Wolfson WM831x PMIC touchscreen controllers

Some of the WM831x series of PMICs from Wolfson Microelectronics include
a resistive touchscreen controller. Implement support for these controllers
within the input API.

Platform data is supported to allow configuration of system parameters such
as selection between four and five wire touchscreens and for specification
of optional direct to CPU IRQs for sample availability and for pen down.
Use of this feature for at least the data IRQ is strongly recommended.

Thanks to Julien Boibessot for extensive testing and detailed feedback.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: Julien Boibessot <julien.boibessot@armadeus.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Mark Brown 2011-01-30 12:31:30 -08:00 committed by Dmitry Torokhov
parent 3c36e71903
commit 00cfa730db
4 changed files with 368 additions and 1 deletions

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@ -423,6 +423,16 @@ config TOUCHSCREEN_UCB1400
To compile this driver as a module, choose M here: the
module will be called ucb1400_ts.
config TOUCHSCREEN_WM831X
tristate "Support for WM831x touchscreen controllers"
depends on MFD_WM831X
help
This enables support for the touchscreen controller on the WM831x
series of PMICs.
To compile this driver as a module, choose M here: the
module will be called wm831x-ts.
config TOUCHSCREEN_WM97XX
tristate "Support for WM97xx AC97 touchscreen controllers"
depends on AC97_BUS

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@ -48,6 +48,7 @@ obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o
obj-$(CONFIG_TOUCHSCREEN_TSC2007) += tsc2007.o
obj-$(CONFIG_TOUCHSCREEN_UCB1400) += ucb1400_ts.o
obj-$(CONFIG_TOUCHSCREEN_WACOM_W8001) += wacom_w8001.o
obj-$(CONFIG_TOUCHSCREEN_WM831X) += wm831x-ts.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX) += wm97xx-ts.o
wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9705) += wm9705.o
wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9712) += wm9712.o

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@ -0,0 +1,355 @@
/*
* Touchscreen driver for WM831x PMICs
*
* Copyright 2011 Wolfson Microelectronics plc.
* Author: Mark Brown <broonie@opensource.wolfsonmicro.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; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/pm.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/irq.h>
#include <linux/mfd/wm831x/pdata.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/types.h>
/*
* R16424 (0x4028) - Touch Control 1
*/
#define WM831X_TCH_ENA 0x8000 /* TCH_ENA */
#define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */
#define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */
#define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */
#define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */
#define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */
#define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */
#define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */
#define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */
#define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */
#define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */
#define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */
/*
* R16425 (0x4029) - Touch Control 2
*/
#define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */
#define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */
#define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */
#define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */
#define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */
#define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */
#define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */
/*
* R16426-8 (0x402A-C) - Touch Data X/Y/X
*/
#define WM831X_TCH_PD 0x8000 /* TCH_PD1 */
#define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */
#define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */
#define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */
struct wm831x_ts {
struct input_dev *input_dev;
struct wm831x *wm831x;
unsigned int data_irq;
unsigned int pd_irq;
bool pressure;
bool pen_down;
};
static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data)
{
struct wm831x_ts *wm831x_ts = irq_data;
struct wm831x *wm831x = wm831x_ts->wm831x;
static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE };
u16 data[3];
int count = wm831x_ts->pressure ? 3 : 2;
int i, ret;
wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count,
data);
if (ret != 0) {
dev_err(wm831x->dev, "Failed to read touch data: %d\n",
ret);
return IRQ_NONE;
}
/*
* We get a pen down reading on every reading, report pen up if any
* individual reading does so.
*/
wm831x_ts->pen_down = true;
for (i = 0; i < count; i++) {
if (!(data[i] & WM831X_TCH_PD)) {
wm831x_ts->pen_down = false;
continue;
}
input_report_abs(wm831x_ts->input_dev, data_types[i],
data[i] & WM831X_TCH_DATA_MASK);
}
if (!wm831x_ts->pen_down) {
disable_irq_nosync(wm831x_ts->data_irq);
/* Don't need data any more */
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
WM831X_TCH_Z_ENA, 0);
/* Flush any final samples that arrived while reading */
wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data);
if (wm831x_ts->pressure)
input_report_abs(wm831x_ts->input_dev,
ABS_PRESSURE, 0);
input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0);
}
input_sync(wm831x_ts->input_dev);
return IRQ_HANDLED;
}
static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data)
{
struct wm831x_ts *wm831x_ts = irq_data;
struct wm831x *wm831x = wm831x_ts->wm831x;
int ena;
/* Start collecting data */
ena = wm831x_ts->pressure ? WM831X_TCH_Z_ENA : 0;
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA,
WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena);
input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
input_sync(wm831x_ts->input_dev);
wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);
wm831x_ts->pen_down = true;
enable_irq(wm831x_ts->data_irq);
return IRQ_HANDLED;
}
static int wm831x_ts_input_open(struct input_dev *idev)
{
struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
struct wm831x *wm831x = wm831x_ts->wm831x;
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_ENA, WM831X_TCH_ENA);
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA);
return 0;
}
static void wm831x_ts_input_close(struct input_dev *idev)
{
struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
struct wm831x *wm831x = wm831x_ts->wm831x;
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_ENA | WM831X_TCH_CVT_ENA |
WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
WM831X_TCH_Z_ENA, 0);
if (wm831x_ts->pen_down)
disable_irq(wm831x_ts->data_irq);
}
static __devinit int wm831x_ts_probe(struct platform_device *pdev)
{
struct wm831x_ts *wm831x_ts;
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent);
struct wm831x_touch_pdata *pdata =
core_pdata ? core_pdata->touch : NULL;
struct input_dev *input_dev;
int error;
wm831x_ts = kzalloc(sizeof(struct wm831x_ts), GFP_KERNEL);
input_dev = input_allocate_device();
if (!wm831x_ts || !input_dev) {
error = -ENOMEM;
goto err_alloc;
}
wm831x_ts->wm831x = wm831x;
wm831x_ts->input_dev = input_dev;
/*
* If we have a direct IRQ use it, otherwise use the interrupt
* from the WM831x IRQ controller.
*/
if (pdata && pdata->data_irq)
wm831x_ts->data_irq = pdata->data_irq;
else
wm831x_ts->data_irq = platform_get_irq_byname(pdev, "TCHDATA");
if (pdata && pdata->pd_irq)
wm831x_ts->pd_irq = pdata->pd_irq;
else
wm831x_ts->pd_irq = platform_get_irq_byname(pdev, "TCHPD");
wm831x_ts->pressure = pdata && pdata->pressure;
/* Five wire touchscreens can't report pressure */
if (pdata && pdata->fivewire) {
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
WM831X_TCH_5WIRE, WM831X_TCH_5WIRE);
/* Pressure measurements are not possible for five wire mode */
WARN_ON(pdata->pressure && pdata->fivewire);
wm831x_ts->pressure = false;
} else {
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
WM831X_TCH_5WIRE, 0);
}
if (pdata) {
switch (pdata->isel) {
default:
dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n",
pdata->isel);
/* Fall through */
case 200:
case 0:
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
WM831X_TCH_ISEL, 0);
break;
case 400:
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
WM831X_TCH_ISEL, WM831X_TCH_ISEL);
break;
}
}
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
WM831X_TCH_PDONLY, 0);
/* Default to 96 samples/sec */
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_RATE_MASK, 6);
error = request_threaded_irq(wm831x_ts->data_irq,
NULL, wm831x_ts_data_irq,
IRQF_ONESHOT,
"Touchscreen data", wm831x_ts);
if (error) {
dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n",
wm831x_ts->data_irq, error);
goto err_alloc;
}
disable_irq(wm831x_ts->data_irq);
error = request_threaded_irq(wm831x_ts->pd_irq,
NULL, wm831x_ts_pen_down_irq,
IRQF_ONESHOT,
"Touchscreen pen down", wm831x_ts);
if (error) {
dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n",
wm831x_ts->pd_irq, error);
goto err_data_irq;
}
/* set up touch configuration */
input_dev->name = "WM831x touchscreen";
input_dev->phys = "wm831x";
input_dev->open = wm831x_ts_input_open;
input_dev->close = wm831x_ts_input_close;
__set_bit(EV_ABS, input_dev->evbit);
__set_bit(EV_KEY, input_dev->evbit);
__set_bit(BTN_TOUCH, input_dev->keybit);
input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0);
if (wm831x_ts->pressure)
input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0);
input_set_drvdata(input_dev, wm831x_ts);
input_dev->dev.parent = &pdev->dev;
error = input_register_device(input_dev);
if (error)
goto err_pd_irq;
platform_set_drvdata(pdev, wm831x_ts);
return 0;
err_pd_irq:
free_irq(wm831x_ts->pd_irq, wm831x_ts);
err_data_irq:
free_irq(wm831x_ts->data_irq, wm831x_ts);
err_alloc:
input_free_device(input_dev);
kfree(wm831x_ts);
return error;
}
static __devexit int wm831x_ts_remove(struct platform_device *pdev)
{
struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev);
free_irq(wm831x_ts->pd_irq, wm831x_ts);
free_irq(wm831x_ts->data_irq, wm831x_ts);
input_unregister_device(wm831x_ts->input_dev);
kfree(wm831x_ts);
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver wm831x_ts_driver = {
.driver = {
.name = "wm831x-touch",
.owner = THIS_MODULE,
},
.probe = wm831x_ts_probe,
.remove = __devexit_p(wm831x_ts_remove),
};
static int __init wm831x_ts_init(void)
{
return platform_driver_register(&wm831x_ts_driver);
}
module_init(wm831x_ts_init);
static void __exit wm831x_ts_exit(void)
{
platform_driver_unregister(&wm831x_ts_driver);
}
module_exit(wm831x_ts_exit);
/* Module information */
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-touch");

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@ -80,7 +80,8 @@ struct wm831x_touch_pdata {
int isel; /** Current for pen down (uA) */
int rpu; /** Pen down sensitivity resistor divider */
int pressure; /** Report pressure (boolean) */
int data_irq; /** Touch data ready IRQ */
unsigned int data_irq; /** Touch data ready IRQ */
unsigned int pd_irq; /** Touch pendown detect IRQ */
};
enum wm831x_watchdog_action {