]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
Input: add tsc2007 based touchscreen driver
authorKwangwoo Lee <kwangwoo.lee@gmail.com>
Sat, 20 Dec 2008 09:26:01 +0000 (04:26 -0500)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Sat, 20 Dec 2008 10:00:43 +0000 (05:00 -0500)
This drive has been tested on ARM9 based SoC - MV86XX.

Signed-off-by: Kwangwoo Lee <kwangwoo.lee@gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
drivers/input/touchscreen/Kconfig
drivers/input/touchscreen/Makefile
drivers/input/touchscreen/tsc2007.c [new file with mode: 0644]
include/linux/i2c/tsc2007.h [new file with mode: 0644]

index 20eb52ed176d5e8d13ee01c9ce1ff55a9ea3fcd4..83747dc9ba0524b942037bac9a40a4b3542069d0 100644 (file)
@@ -389,4 +389,15 @@ 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 touchscreen.
+
+         If unsure, say N.
+
+         To compile this driver as a module, choose M here: the
+         module will be called tsc2007.
+
 endif
index 3dc84d3846c14ffebecc5d45bce3309ed93ca7b0..127f87cc2e2ee3ff3775827f97c86b64953a842b 100644 (file)
@@ -25,6 +25,7 @@ obj-$(CONFIG_TOUCHSCREEN_PENMOUNT)    += penmount.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213)   += touchit213.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT)   += touchright.o
 obj-$(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_WM97XX)       += wm97xx-ts.o
diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
new file mode 100644 (file)
index 0000000..b75dc29
--- /dev/null
@@ -0,0 +1,381 @@
+/*
+ * drivers/input/touchscreen/tsc2007.c
+ *
+ * Copyright (c) 2008 MtekVision Co., Ltd.
+ *     Kwangwoo Lee <kwlee@mtekvision.com>
+ *
+ * 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/module.h>
+#include <linux/hrtimer.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/i2c/tsc2007.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 inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
+{
+       s32 data;
+       u16 val;
+
+       data = i2c_smbus_read_word_data(tsc->client, cmd);
+       if (data < 0) {
+               dev_err(&tsc->client->dev, "i2c io error: %d\n", data);
+               return data;
+       }
+
+       /* The protocol and raw data format from i2c interface:
+        * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
+        * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit].
+        */
+       val = swab16(data) >> 4;
+
+       dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val);
+
+       return val;
+}
+
+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)
+{
+       /* y- still on; turn on only y+ (and ADC) */
+       tsc->tc.y = tsc2007_xfer(tsc, READ_Y);
+
+       /* turn y- off, x+ on, then leave in lowpower */
+       tsc->tc.x = tsc2007_xfer(tsc, READ_X);
+
+       /* turn y+ off, x- on; we'll use formula #1 */
+       tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1);
+       tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2);
+
+       /* power down */
+       tsc2007_xfer(tsc, 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 tsc2007 *ts;
+       struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
+       struct input_dev *input_dev;
+       int err;
+
+       if (!pdata) {
+               dev_err(&client->dev, "platform data is required!\n");
+               return -EINVAL;
+       }
+
+       if (!i2c_check_functionality(client->adapter,
+                                    I2C_FUNC_SMBUS_READ_WORD_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->id.bustype = BUS_I2C;
+
+       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;
+
+       err = request_irq(ts->irq, tsc2007_irq, 0,
+                       client->dev.driver->name, ts);
+       if (err < 0) {
+               dev_err(&client->dev, "irq %d busy?\n", ts->irq);
+               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);
+       hrtimer_cancel(&ts->timer);
+ 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();
+
+       free_irq(ts->irq, ts);
+       hrtimer_cancel(&ts->timer);
+       input_unregister_device(ts->input);
+       kfree(ts);
+
+       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@mtekvision.com>");
+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 (file)
index 0000000..c6361fb
--- /dev/null
@@ -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