// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Touchscreen driver for WM831x PMICs
*
* Copyright 2011 Wolfson Microelectronics plc.
* Author: Mark Brown <[email protected]>
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.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;
struct work_struct pd_data_work;
};
static void wm831x_pd_data_work(struct work_struct *work)
{
struct wm831x_ts *wm831x_ts =
container_of(work, struct wm831x_ts, pd_data_work);
if (wm831x_ts->pen_down) {
enable_irq(wm831x_ts->data_irq);
dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n");
} else {
enable_irq(wm831x_ts->pd_irq);
dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n");
}
}
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;
int i, ret;
if (wm831x_ts->pressure)
count = 3;
else
count = 2;
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) {
/* Switch from data to pen down */
dev_dbg(wm831x->dev, "IRQ DATA->PD\n");
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);
schedule_work(&wm831x_ts->pd_data_work);
} else {
input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
}
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 = 0;
if (wm831x_ts->pen_down)
return IRQ_HANDLED;
disable_irq_nosync(wm831x_ts->pd_irq);
/* Start collecting data */
if (wm831x_ts->pressure)
ena |= WM831X_TCH_Z_ENA;
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);
wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);
wm831x_ts->pen_down = true;
/* Switch from pen down to data */
dev_dbg(wm831x->dev, "IRQ PD->DATA\n");
schedule_work(&wm831x_ts->pd_data_work);
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_CVT_ENA |
WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
WM831X_TCH_Z_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;
/* Shut the controller down, disabling all other functionality too */
wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
WM831X_TCH_ENA | WM831X_TCH_X_ENA |
WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0);
/* Make sure any pending IRQs are done, the above will prevent
* new ones firing.
*/
synchronize_irq(wm831x_ts->data_irq);
synchronize_irq(wm831x_ts->pd_irq);
/* Make sure the IRQ completion work is quiesced */
flush_work(&wm831x_ts->pd_data_work);
/* If we ended up with the pen down then make sure we revert back
* to pen detection state for the next time we start up.
*/
if (wm831x_ts->pen_down) {
disable_irq(wm831x_ts->data_irq);
enable_irq(wm831x_ts->pd_irq);
wm831x_ts->pen_down = false;
}
}
static 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 = NULL;
struct input_dev *input_dev;
int error, irqf;
if (core_pdata)
pdata = core_pdata->touch;
wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts),
GFP_KERNEL);
input_dev = devm_input_allocate_device(&pdev->dev);
if (!wm831x_ts || !input_dev) {
error = -ENOMEM;
goto err_alloc;
}
wm831x_ts->wm831x = wm831x;
wm831x_ts->input_dev = input_dev;
INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work);
/*
* If we have a direct IRQ use it, otherwise use the interrupt
* from the WM831x IRQ controller.
*/
wm831x_ts->data_irq = wm831x_irq(wm831x,
platform_get_irq_byname(pdev,
"TCHDATA"));
if (pdata && pdata->data_irq)
wm831x_ts->data_irq = pdata->data_irq;
wm831x_ts->pd_irq = wm831x_irq(wm831x,
platform_get_irq_byname(pdev, "TCHPD"));
if (pdata && pdata->pd_irq)
wm831x_ts->pd_irq = pdata->pd_irq;
if (pdata)
wm831x_ts->pressure = pdata->pressure;
else
wm831x_ts->pressure = true;
/* 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);
fallthrough;
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);
if (pdata && pdata->data_irqf)
irqf = pdata->data_irqf;
else
irqf = IRQF_TRIGGER_HIGH;
error = request_threaded_irq(wm831x_ts->data_irq,
NULL, wm831x_ts_data_irq,
irqf | IRQF_ONESHOT | IRQF_NO_AUTOEN,
"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;
}
if (pdata && pdata->pd_irqf)
irqf = pdata->pd_irqf;
else
irqf = IRQF_TRIGGER_HIGH;
error = request_threaded_irq(wm831x_ts->pd_irq,
NULL, wm831x_ts_pen_down_irq,
irqf | 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:
return error;
}
static void 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);
}
static struct platform_driver wm831x_ts_driver = {
.driver = {
.name = "wm831x-touch",
},
.probe = wm831x_ts_probe,
.remove_new = wm831x_ts_remove,
};
module_platform_driver(wm831x_ts_driver);
/* Module information */
MODULE_AUTHOR("Mark Brown <[email protected]>");
MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-touch");
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