[PATCH] Touchscreen driver for the DTS413
Jernej Turnsek
jernej.turnsek at gmail.com
Mon Sep 28 03:23:05 EDT 2009
Hi,
we have developed a support for a nice capacitive ITO touchscreen from
Densitron (DTS413). It is connected to the I2C bus.
Simple DTS413 Touchscreen driver.
Signed-off-by: Jernej Turnsek <jernej.turnsek at gmail.com>
diff --git a/drivers/input/touchscreen/Kconfig
b/drivers/input/touchscreen/Kconfig
index ab02d72..b2403f5 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -510,6 +510,17 @@ config TOUCHSCREEN_W90X900
To compile this driver as a module, choose M here: the
module will be called w90p910_ts.
+config TOUCHSCREEN_DTS413
+ tristate "DTS413 based touchscreens"
+ depends on I2C
+ help
+ Say Y here if you have a DTS413 based touchscreen.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called dts413.
+
config TOUCHSCREEN_PCAP
tristate "Motorola PCAP touchscreen"
depends on EZX_PCAP
diff --git a/drivers/input/touchscreen/Makefile
b/drivers/input/touchscreen/Makefile
index 4599bf7..be7315b 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -40,4 +40,6 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_ATMEL) += atmel-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) += mainstone-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE) += zylonite-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_W90X900) += w90p910_ts.o
+obj-$(CONFIG_TOUCHSCREEN_DTS413) += dts413.o
obj-$(CONFIG_TOUCHSCREEN_PCAP) += pcap_ts.o
+
diff --git a/drivers/input/touchscreen/dts413.c
b/drivers/input/touchscreen/dts413.c
new file mode 100644
index 0000000..b7a43af
--- /dev/null
+++ b/drivers/input/touchscreen/dts413.c
@@ -0,0 +1,282 @@
+/*
+ * drivers/input/touchscreen/dts413.c
+ *
+ * Copyright (c) 2009 Iskraemeco d.d.
+ * Jernej Turnsek <jernej.turnsek at iskraemeco.si>
+ *
+ * Using code from:
+ * - migor_ts.c
+ * Copyright (c) 2008 Magnus Damm
+ * Copyright (c) 2007 Ujjwal Pande <ujjwal at kenati.com>,
+ * Kenati Technologies Pvt Ltd.
+ *
+ * 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/kernel.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <asm/io.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+
+#define MAX_11BIT ((1 << 11) - 1)
+
+#define EVENT_PENDOWN 1
+#define EVENT_PENUP 0
+
+struct ts_event {
+ u8 byte0_stat: 1;
+ u8 byte0_res : 7;
+ u8 byte1_xpos_msb : 4;
+ u8 byte1_res : 4;
+ u8 byte2_xpos_lsb : 7;
+ u8 byte2_res : 1;
+ u8 byte3_ypos_msb : 4;
+ u8 byte3_res : 4;
+ u8 byte4_ypos_lsb : 7;
+ u8 byte4_res : 1;
+ u8 byte5_speed : 6;
+ u8 byte5_res : 2;
+};
+
+struct dts413 {
+ struct i2c_client *client;
+ struct input_dev *input;
+ struct delayed_work work;
+ int irq;
+};
+
+
+static void dts413_poscheck(struct work_struct *work)
+{
+ struct dts413 *priv = container_of(work,
+ struct dts413,
+ work.work);
+ unsigned short xpos, ypos;
+ unsigned char event;
+ u_int8_t buf[6];
+ struct ts_event *ts = (struct ts_event *)&buf[0];
+
+ memset(buf, 0, sizeof(buf));
+
+ /* Now do Page Read */
+ if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) {
+ dev_err(&priv->client->dev, "Unable to read i2c page\n");
+ goto out;
+ }
+
+ xpos = (unsigned short)(ts->byte1_xpos_msb << 7) | (ts->byte2_xpos_lsb);
+ ypos = (unsigned short)(ts->byte3_ypos_msb << 7) | (ts->byte4_ypos_lsb);
+ event = (unsigned char)ts->byte0_stat;
+
+ if (event == EVENT_PENDOWN) {
+ input_report_key(priv->input, BTN_TOUCH, 1);
+ input_report_abs(priv->input, ABS_X, xpos);
+ input_report_abs(priv->input, ABS_Y, 2048 - ypos);
+ input_report_abs(priv->input, ABS_PRESSURE, 1);
+ input_sync(priv->input);
+ } else if (event == EVENT_PENUP) {
+ input_report_key(priv->input, BTN_TOUCH, 0);
+ input_report_abs(priv->input, ABS_PRESSURE, 0);
+ input_sync(priv->input);
+ }
+ out:
+ enable_irq(priv->irq);
+}
+
+static irqreturn_t dts413_isr(int irq, void *dev_id)
+{
+ struct dts413 *priv = (struct dts413*)dev_id;
+
+ /* the touch screen controller chip is hooked up to the cpu
+ * using i2c and a single interrupt line. the interrupt line
+ * is pulled low whenever someone taps the screen. to deassert
+ * the interrupt line we need to acknowledge the interrupt by
+ * communicating with the controller over the slow i2c bus.
+ *
+ * we can't acknowledge from interrupt context since the i2c
+ * bus controller may sleep, so we just disable the interrupt
+ * here and handle the acknowledge using delayed work.
+ */
+
+ disable_irq_nosync(irq);
+ schedule_delayed_work(&priv->work, HZ / 100);
+
+ return IRQ_HANDLED;
+}
+
+static int dts413_open(struct input_dev *dev)
+{
+ //struct dts413 *priv = input_get_drvdata(dev);
+ //struct i2c_client *client = priv->client;
+
+ /* enable controller */
+ //todo
+
+ return 0;
+}
+
+static void dts413_close(struct input_dev *dev)
+{
+ struct dts413 *priv = input_get_drvdata(dev);
+ //struct i2c_client *client = priv->client;
+
+ disable_irq(priv->irq);
+
+ /* cancel pending work and wait for dts413_poscheck() to finish */
+ if (cancel_delayed_work_sync(&priv->work)) {
+ /*
+ * if migor_ts_poscheck was canceled we need to enable IRQ
+ * here to balance disable done in migor_ts_isr.
+ */
+ enable_irq(priv->irq);
+ }
+
+ /* disable controller */
+ //todo
+
+ enable_irq(priv->irq);
+}
+
+
+static int dts413_probe(struct i2c_client *client,
+ const struct i2c_device_id *idp)
+{
+ struct dts413 *priv;
+ struct input_dev *input;
+ int error;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&client->dev, "failed to allocate driver data\n");
+ error = -ENOMEM;
+ goto err0;
+ }
+
+ dev_set_drvdata(&client->dev, priv);
+
+ input = input_allocate_device();
+ if (!input) {
+ dev_err(&client->dev, "Failed to allocate input device.\n");
+ error = -ENOMEM;
+ goto err1;
+ }
+
+ input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ input_set_abs_params(input, ABS_X, 0, MAX_11BIT, 0, 0);
+ input_set_abs_params(input, ABS_Y, 0, MAX_11BIT, 0, 0);
+ input_set_abs_params(input, ABS_PRESSURE, 0, 0, 0, 0);
+
+ input->name = client->name;
+ input->id.bustype = BUS_I2C;
+ input->dev.parent = &client->dev;
+
+ input->open = dts413_open;
+ input->close = dts413_close;
+
+ input_set_drvdata(input, priv);
+
+ priv->client = client;
+ priv->input = input;
+ INIT_DELAYED_WORK(&priv->work, dts413_poscheck);
+ priv->irq = client->irq;
+
+ error = input_register_device(input);
+ if (error)
+ goto err1;
+
+ error = request_irq(priv->irq, dts413_isr,
IRQF_TRIGGER_FALLING/*IRQF_TRIGGER_LOW*/,
+ client->name, priv);
+ if (error) {
+ dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+ goto err2;
+ }
+
+ device_init_wakeup(&client->dev, 1);
+ return 0;
+
+ err2:
+ input_unregister_device(input);
+ input = NULL; /* so we dont try to free it below */
+ err1:
+ input_free_device(input);
+ kfree(priv);
+ err0:
+ dev_set_drvdata(&client->dev, NULL);
+ return error;
+}
+
+static int dts413_remove(struct i2c_client *client)
+{
+ struct dts413 *priv = dev_get_drvdata(&client->dev);
+
+ free_irq(priv->irq, priv);
+ input_unregister_device(priv->input);
+ kfree(priv);
+
+ dev_set_drvdata(&client->dev, NULL);
+
+ return 0;
+}
+
+static int dts413_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ struct dts413 *priv = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+static int dts413_resume(struct i2c_client *client)
+{
+ struct dts413 *priv = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+static struct i2c_device_id dts413_idtable[] = {
+ { "dts413", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, dts413_idtable);
+
+static struct i2c_driver dts413_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "dts413"
+ },
+ .id_table = dts413_idtable,
+ .probe = dts413_probe,
+ .remove = __devexit_p(dts413_remove),
+ .suspend = dts413_suspend,
+ .resume = dts413_resume,
+};
+
+static int __init dts413_init(void)
+{
+ return i2c_add_driver(&dts413_driver);
+}
+
+static void __exit dts413_exit(void)
+{
+ i2c_del_driver(&dts413_driver);
+}
+
+module_init(dts413_init);
+module_exit(dts413_exit);
+
+MODULE_AUTHOR("Jernej Turnsek <jernej.turnsek at iskraemeco.si>");
+MODULE_DESCRIPTION("DTS413 Touch Screen Controller driver");
+MODULE_LICENSE("GPL");
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