[PATCH] Add tsc2007 based touchscreen driver.
From: Kwangwoo Lee
Date: Tue Dec 02 2008 - 08:39:33 EST
Hello,
I'm newbie and I tested this driver on my ARM9 based SoC - MV86XX.
But the platform codes are not submitted yet.
The example of platform specific codes are followed:
/* TSC2007 Touchscreen */
#ifdef CONFIG_LCD_CT024TN02
/* GPIO13:GINT3 = PENIRQ */
#define TS_PENIRQ_GPIO GPIO13
#define TS_CHAINED_GPIO 3
#else
/* GPIO5:GINT1 = PENIRQ */
#define TS_PENIRQ_GPIO GPIO5
#define TS_CHAINED_GPIO 1
#endif
static int mv_get_pendown_state(void)
{
int val = 0;
mv_gpio_set_direction(TS_PENIRQ_GPIO, 0);
mv_gpio_mux_ctrl(TS_PENIRQ_GPIO, GPIO_PIN_MODE_GPIO);
val = mv_gpio_get_value(TS_PENIRQ_GPIO);
mv_gpio_mux_ctrl(TS_PENIRQ_GPIO, GPIO_PIN_MODE_INT);
val = val ? 0 : 1;
return val;
}
static void mv_clear_penirq(void)
{
mv_gpio_int_clear(TS_CHAINED_GPIO);
}
static int mv_init_ts(void)
{
mv_gpio_set_direction(TS_PENIRQ_GPIO, 0); /* input */
mv_gpio_mux_ctrl(TS_PENIRQ_GPIO, GPIO_PIN_MODE_INT);
mv_gpio_int_mode(TS_CHAINED_GPIO, GPIO_INT_FALLING_EDGE);
mv_gpio_int_clear(TS_CHAINED_GPIO);
mv_gpio_int_unmask(TS_CHAINED_GPIO);
return 0;
}
static void mv_exit_ts(void)
{
mv_gpio_mux_ctrl(TS_PENIRQ_GPIO, GPIO_PIN_MODE_GPIO);
mv_gpio_int_mask(TS_CHAINED_GPIO);
}
struct tsc2007_platform_data mv_tsc2007_data = {
.model = 2007,
.x_plate_ohms = 180,
.get_pendown_state = mv_get_pendown_state,
.clear_penirq = mv_clear_penirq,
.init_platform_hw = mv_init_ts,
.exit_platform_hw = mv_exit_ts,
};
/* I2C clients */
static struct i2c_board_info __initdata mv_i2c_clients[] = {
[0] = {
I2C_BOARD_INFO("tsc2007", 0x90),
.type = "tsc2007",
.platform_data = &mv_tsc2007_data,
.irq = IRQ_GPIO,
},
};
i2c_register_board_info() should be used.
Signed-off-by: Kwangwoo Lee <kwangwoo.lee@xxxxxxxxx>
---
drivers/input/touchscreen/Kconfig | 9 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/tsc2007.c | 398 +++++++++++++++++++++++++++++++++++
include/linux/i2c/tsc2007.h | 17 ++
4 files changed, 425 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/tsc2007.c
create mode 100644 include/linux/i2c/tsc2007.h
diff --git a/drivers/input/touchscreen/Kconfig
b/drivers/input/touchscreen/Kconfig
index 3d1ab8f..78abdfb 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -376,4 +376,13 @@ config TOUCHSCREEN_TOUCHIT213
To compile this driver as a module, choose M here: the
module will be called touchit213.
+config TOUCHSCREEN_TSC2007
+ tristate "TSC2007 based touchscreens"
+ depends on I2C
+ help
+ Say Y here if you have a TSC2007 based touchscreens.
+
+ To compile this driver as a module, choose M here: the
+ module will be called tsc2007.
+
endif
diff --git a/drivers/input/touchscreen/Makefile
b/drivers/input/touchscreen/Makefile
index 15cf290..824999c 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -31,3 +31,4 @@ 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_TSC2007) += tsc2007.o
diff --git a/drivers/input/touchscreen/tsc2007.c
b/drivers/input/touchscreen/tsc2007.c
new file mode 100644
index 0000000..85fb520
--- /dev/null
+++ b/drivers/input/touchscreen/tsc2007.c
@@ -0,0 +1,398 @@
+/*
+ * drivers/input/touchscreen/tsc2007.c
+ *
+ * Copyright (c) 2008 MtekVision Co., Ltd.
+ * Kwangwoo Lee <kwlee@xxxxxxxxxxxxxx>
+ *
+ * Using code from:
+ * - ads7846.c
+ * Copyright (c) 2005 David Brownell
+ * Copyright (c) 2006 Nokia Corporation
+ * - corgi_ts.c
+ * Copyright (C) 2004-2005 Richard Purdie
+ * - omap_ts.[hc], ads7846.h, ts_osk.c
+ * Copyright (C) 2002 MontaVista Software
+ * Copyright (C) 2004 Texas Instruments
+ * Copyright (C) 2005 Dirk Behme
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/hwmon.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/i2c/tsc2007.h>
+#include <linux/io.h>
+
+#include <asm/irq.h>
+
+#define TS_POLL_DELAY (10 * 1000) /* ns delay before the first sample */
+#define TS_POLL_PERIOD (5 * 1000) /* ns delay between samples */
+
+#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
+#define TSC2007_MEASURE_AUX (0x2 << 4)
+#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
+#define TSC2007_ACTIVATE_XN (0x8 << 4)
+#define TSC2007_ACTIVATE_YN (0x9 << 4)
+#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
+#define TSC2007_SETUP (0xb << 4)
+#define TSC2007_MEASURE_X (0xc << 4)
+#define TSC2007_MEASURE_Y (0xd << 4)
+#define TSC2007_MEASURE_Z1 (0xe << 4)
+#define TSC2007_MEASURE_Z2 (0xf << 4)
+
+#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
+#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
+#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
+#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
+
+#define TSC2007_12BIT (0x0 << 1)
+#define TSC2007_8BIT (0x1 << 1)
+
+#define MAX_12BIT ((1 << 12) - 1)
+
+#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
+
+#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
+#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
+#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
+#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
+#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
+
+struct ts_event {
+ u16 x;
+ u16 y;
+ u16 z1, z2;
+};
+
+struct tsc2007 {
+ struct input_dev *input;
+ char phys[32];
+ struct hrtimer timer;
+ struct ts_event tc;
+
+ struct i2c_client *client;
+
+ spinlock_t lock;
+
+ u16 model;
+ u16 x_plate_ohms;
+
+ unsigned pendown;
+ int irq;
+
+ int (*get_pendown_state)(void);
+ void (*clear_penirq)(void);
+};
+
+static int tsc2007_xfer(void *tsc, unsigned char cmd)
+{
+ struct tsc2007 *ts = tsc;
+ struct i2c_client *client = ts->client;
+
+ unsigned char rbuf[2];
+ unsigned short val;
+ int result;
+
+ result = i2c_master_send(client, &cmd, 1);
+ if (result != 1) {
+ dev_err(&client->dev, "send failed, cmd 0x%x\n", cmd);
+ goto cmd_fail;
+ }
+
+ result = i2c_master_recv(client, rbuf, 2);
+ if (result != 2) {
+ dev_err(&client->dev, "recv failed, cmd 0x%x\n", cmd);
+ goto cmd_fail;
+ }
+
+ rbuf[1] = (rbuf[1] >> 4) | ((rbuf[0] & 0x0f) << 4);
+ rbuf[0] = rbuf[0] >> 4;
+
+ val = *((unsigned short *) rbuf);
+ val = be16_to_cpu(val);
+
+ dev_dbg(&client->dev, "cmd [0x%x], rbuf [0x%x, 0x%x] => val [%u]\n",
+ cmd, rbuf[0], rbuf[1], val);
+
+ return (int) val;
+
+cmd_fail:
+ return -EIO;
+}
+
+static void tsc2007_send_event(void *tsc)
+{
+ struct tsc2007 *ts = tsc;
+ u32 Rt;
+ u16 x, y, z1, z2;
+
+ x = ts->tc.x;
+ y = ts->tc.y;
+ z1 = ts->tc.z1;
+ z2 = ts->tc.z2;
+
+ /* range filtering */
+ if (x == MAX_12BIT)
+ x = 0;
+
+ if (likely(x && z1)) {
+ /* compute touch pressure resistance using equation #1 */
+ Rt = z2;
+ Rt -= z1;
+ Rt *= x;
+ Rt *= ts->x_plate_ohms;
+ Rt /= z1;
+ Rt = (Rt + 2047) >> 12;
+ } else
+ Rt = 0;
+
+ /* Sample found inconsistent by debouncing or pressure is beyond
+ * the maximum. Don't report it to user space, repeat at least
+ * once more the measurement
+ */
+ if (Rt > MAX_12BIT) {
+ dev_dbg(&ts->client->dev, "ignored pressure %d\n", Rt);
+
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
+ return;
+ }
+
+ /* NOTE: We can't rely on the pressure to determine the pen down
+ * state, even this controller has a pressure sensor. The pressure
+ * value can fluctuate for quite a while after lifting the pen and
+ * in some cases may not even settle at the expected value.
+ *
+ * The only safe way to check for the pen up condition is in the
+ * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+ */
+ if (Rt) {
+ struct input_dev *input = ts->input;
+
+ if (!ts->pendown) {
+ dev_dbg(&ts->client->dev, "DOWN\n");
+
+ input_report_key(input, BTN_TOUCH, 1);
+ ts->pendown = 1;
+ }
+
+ input_report_abs(input, ABS_X, x);
+ input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_PRESSURE, Rt);
+
+ input_sync(input);
+
+ dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
+ x, y, Rt);
+ }
+
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
+}
+
+static int tsc2007_read_values(struct tsc2007 *tsc)
+{
+ struct tsc2007 *ts = tsc;
+
+ /* y- still on; turn on only y+ (and ADC) */
+ ts->tc.y = tsc2007_xfer(ts, READ_Y);
+
+ /* turn y- off, x+ on, then leave in lowpower */
+ ts->tc.x = tsc2007_xfer(ts, READ_X);
+
+ /* turn y+ off, x- on; we'll use formula #1 */
+ ts->tc.z1 = tsc2007_xfer(ts, READ_Z1);
+ ts->tc.z2 = tsc2007_xfer(ts, READ_Z2);
+
+ /* power down */
+ tsc2007_xfer(ts, PWRDOWN);
+ return 0;
+}
+
+static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle)
+{
+ struct tsc2007 *ts = container_of(handle, struct tsc2007, timer);
+
+ spin_lock_irq(&ts->lock);
+
+ if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
+ struct input_dev *input = ts->input;
+
+ dev_dbg(&ts->client->dev, "UP\n");
+
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+
+ ts->pendown = 0;
+ enable_irq(ts->irq);
+ } else {
+ /* pen is still down, continue with the measurement */
+ dev_dbg(&ts->client->dev, "pen is still down\n");
+
+ tsc2007_read_values(ts);
+ tsc2007_send_event(ts);
+ }
+
+ spin_unlock_irq(&ts->lock);
+ return HRTIMER_NORESTART;
+}
+
+static irqreturn_t tsc2007_irq(int irq, void *handle)
+{
+ struct tsc2007 *ts = handle;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ if (likely(ts->get_pendown_state())) {
+ disable_irq(ts->irq);
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
+ HRTIMER_MODE_REL);
+ }
+
+ if (ts->clear_penirq)
+ ts->clear_penirq();
+
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static int tsc2007_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+ struct tsc2007 *ts;
+ struct tsc2007_platform_data *pdata;
+ struct input_dev *input_dev;
+ int err;
+
+ pdata = client->dev.platform_data;
+ if (pdata == NULL) {
+ dev_err(&client->dev, "platform data is required!\n");
+ return -EINVAL;
+ }
+
+ if (!i2c_check_functionality(adapter,
+ I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+ return -EIO;
+
+ ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ts || !input_dev) {
+ err = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ ts->client = client;
+ i2c_set_clientdata(client, ts);
+
+ ts->input = input_dev;
+
+ hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ ts->timer.function = tsc2007_timer;
+
+ spin_lock_init(&ts->lock);
+
+ ts->model = pdata->model;
+ ts->x_plate_ohms = pdata->x_plate_ohms;
+ ts->get_pendown_state = pdata->get_pendown_state;
+ ts->clear_penirq = pdata->clear_penirq;
+
+ pdata->init_platform_hw();
+
+ snprintf(ts->phys, sizeof(ts->phys), "%s/input0", client->dev.bus_id);
+
+ input_dev->name = "TSC2007 Touchscreen";
+ input_dev->phys = ts->phys;
+
+ 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, MAX_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
+
+ tsc2007_read_values(ts);
+
+ ts->irq = client->irq;
+ if (request_irq(ts->irq, tsc2007_irq, 0,
+ client->dev.driver->name, ts)) {
+ dev_err(&client->dev, "irq %d busy?\n", ts->irq);
+ err = -EBUSY;
+ goto err_free_mem;
+ }
+
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_free_irq;
+
+ dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
+
+ return 0;
+
+ err_free_irq:
+ free_irq(ts->irq, ts);
+ err_free_mem:
+ input_free_device(input_dev);
+ kfree(ts);
+ return err;
+}
+
+static int tsc2007_remove(struct i2c_client *client)
+{
+ struct tsc2007 *ts = i2c_get_clientdata(client);
+ struct tsc2007_platform_data *pdata;
+
+ pdata = client->dev.platform_data;
+ pdata->exit_platform_hw();
+
+ input_unregister_device(ts->input);
+ free_irq(ts->irq, ts);
+ kfree(ts);
+
+ dev_info(&client->dev, "unregistered\n");
+ return 0;
+}
+
+static struct i2c_device_id tsc2007_idtable[] = {
+ { "tsc2007", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
+
+static struct i2c_driver tsc2007_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "tsc2007"
+ },
+ .id_table = tsc2007_idtable,
+ .probe = tsc2007_probe,
+ .remove = tsc2007_remove,
+};
+
+static int __init tsc2007_init(void)
+{
+ return i2c_add_driver(&tsc2007_driver);
+}
+
+static void __exit tsc2007_exit(void)
+{
+ i2c_del_driver(&tsc2007_driver);
+}
+
+module_init(tsc2007_init);
+module_exit(tsc2007_exit);
+
+MODULE_AUTHOR("Kwangwoo Lee <kwlee@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/i2c/tsc2007.h b/include/linux/i2c/tsc2007.h
new file mode 100644
index 0000000..c6361fb
--- /dev/null
+++ b/include/linux/i2c/tsc2007.h
@@ -0,0 +1,17 @@
+#ifndef __LINUX_I2C_TSC2007_H
+#define __LINUX_I2C_TSC2007_H
+
+/* linux/i2c/tsc2007.h */
+
+struct tsc2007_platform_data {
+ u16 model; /* 2007. */
+ u16 x_plate_ohms;
+
+ int (*get_pendown_state)(void);
+ void (*clear_penirq)(void); /* If needed, clear 2nd level
+ interrupt source */
+ int (*init_platform_hw)(void);
+ void (*exit_platform_hw)(void);
+};
+
+#endif
--
1.5.6.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/