--- /dev/null
+/*
+ * TSC2046 Touchscreen driver
+ *
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * Communication details from original TI driver
+ * Copyright (C) 2004-2005 Texas Instruments, Inc.
+ *
+ * Structure based heavily on TSC2301 driver
+ * Copyright (C) 2005-2006 Nokia Corporation
+ *
+ * 2007 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/spi/spi.h>
+
+#ifdef CONFIG_ARCH_OMAP
+#include <asm/arch/gpio.h>
+#endif
+
+#include <linux/spi/tsc2046.h>
+
+/* TSC2046 commands */
+#define START_BYTE 0x8000
+#define X_CMDWD 0xd300
+#define Y_CMDWD 0x9300
+#define Z1_CMDWD 0xb300
+#define Z2_CMDWD 0xc300
+
+#define TSC2046_TS_SCAN_TIME 1
+#define MAX_12BIT ((1 << 12) - 1)
+
+struct tsc2046_ts {
+ struct input_dev *idev;
+ char phys[32];
+ struct timer_list timer;
+ spinlock_t lock;
+
+ struct spi_transfer read_xfer[3];
+ struct spi_message read_msg;
+ struct spi_message enable_msg;
+ u16 data[5];
+
+ u16 x;
+ u16 y;
+ u16 p;
+ int sample_cnt;
+
+ int ignore_last : 1;
+ u16 x_plate_ohm;
+ int max_pressure;
+ int touch_pressure;
+ int pressure_limit;
+
+ u16 irq_enabled:1;
+ u16 pen_down:1;
+ u16 disabled:1;
+ u16 pending:1;
+
+ s16 dav_gpio;
+ int irq;
+};
+
+static const u16 tsc2046_ts_cmd_data[] = {
+ START_BYTE, X_CMDWD, Y_CMDWD, Z1_CMDWD, Z2_CMDWD,
+};
+
+static int device_suspended(struct device *dev)
+{
+ struct tsc2046 *tsc = dev_get_drvdata(dev);
+ return dev->power.power_state.event != PM_EVENT_ON || tsc->ts->disabled;
+}
+
+static void update_pen_state(struct tsc2046 *tsc, int x, int y, int pressure)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+ int sync = 0;
+
+ if (pressure) {
+ input_report_abs(ts->idev, ABS_X, x);
+ input_report_abs(ts->idev, ABS_Y, y);
+ input_report_abs(ts->idev, ABS_PRESSURE, pressure);
+ if (!ts->pen_down)
+ input_report_key(ts->idev, BTN_TOUCH, 1);
+ sync = 1;
+ } else if (ts->pen_down) {
+ input_report_abs(ts->idev, ABS_PRESSURE, 0);
+ input_report_key(ts->idev, BTN_TOUCH, 0);
+ sync = 1;
+ }
+
+ if (sync)
+ input_sync(ts->idev);
+
+ ts->pen_down = pressure ? 1 : 0;
+
+#ifdef VERBOSE
+ dev_dbg(&tsc->spi->dev, "x %4d y %4d p %4d\n", x, y, pressure);
+#endif
+}
+
+#define CONV_DATA(d1, d2) \
+ (((d1 & 0x7f) << 5) | ((d2 >> 11) & 0x1f))
+
+/*
+ * This procedure is called by the SPI framework after the coordinates
+ * have been read from TSC2046
+ */
+static void tsc2046_ts_rx(void *arg)
+{
+ struct tsc2046 *tsc = arg;
+ struct tsc2046_ts *ts = tsc->ts;
+ unsigned int x, y, z1, z2, pressure;
+
+ x = CONV_DATA(ts->data[2], ts->data[3]);
+ y = CONV_DATA(ts->data[1], ts->data[2]);
+ z1 = CONV_DATA(ts->data[3], ts->data[4]);
+ z2 = CONV_DATA(ts->data[4], 0);
+
+ if (z1) {
+ pressure = ts->x_plate_ohm * x;
+ pressure /= 4096;
+ pressure *= z2 - z1;
+ pressure /= z1;
+ } else
+ pressure = 0;
+
+ /* If pressure value is above a preset limit (pen is barely
+ * touching the screen) we can't trust the coordinate values.
+ */
+ if (pressure < ts->pressure_limit && x < MAX_12BIT && y < MAX_12BIT) {
+ ts->pressure_limit = ts->max_pressure;
+ if (ts->ignore_last) {
+ if (ts->sample_cnt)
+ update_pen_state(tsc, ts->x, ts->y, ts->p);
+ ts->x = x;
+ ts->y = y;
+ ts->p = pressure;
+ } else
+ update_pen_state(tsc, x, y, pressure);
+ ts->sample_cnt++;
+ }
+
+ mod_timer(&ts->timer,
+ jiffies + msecs_to_jiffies(TSC2046_TS_SCAN_TIME));
+}
+
+static int is_pen_down(struct tsc2046_ts *ts)
+{
+ return ts->pen_down;
+}
+
+/*
+ * Timer is called every TSC2046_TS_SCAN_TIME when the pen is down
+ */
+static void tsc2046_ts_timer(unsigned long arg)
+{
+ struct tsc2046 *tsc = (void *) arg;
+ struct tsc2046_ts *ts = tsc->ts;
+ unsigned long flags;
+ int ndav;
+ int r;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ ndav = omap_get_gpio_datain(ts->dav_gpio);
+ if (ndav || device_suspended(&tsc->spi->dev)) {
+ /* Pen has been lifted */
+ if (!device_suspended(&tsc->spi->dev) &&
+ !ts->irq_enabled) {
+ ts->irq_enabled = 1;
+ enable_irq(ts->irq);
+ }
+ update_pen_state(tsc, 0, 0, 0);
+ ts->pending = 0;
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ } else {
+ ts->pen_down = 1;
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ r = spi_async(tsc->spi, &ts->read_msg);
+ if (r)
+ dev_err(&tsc->spi->dev, "ts: spi_async() failed");
+ }
+}
+
+/*
+ * This interrupt is called when pen is down and first coordinates are
+ * available. That is indicated by a falling edge on DEV line. IRQ is
+ * disabled here because while the pen is down the coordinates are
+ * read by a timer.
+ */
+static irqreturn_t tsc2046_ts_irq_handler(int irq, void *dev_id)
+{
+ struct tsc2046 *tsc = dev_id;
+ struct tsc2046_ts *ts = tsc->ts;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ if (ts->irq_enabled) {
+ ts->irq_enabled = 0;
+ disable_irq(ts->irq);
+ ts->pending = 1;
+ ts->pressure_limit = ts->touch_pressure;
+ ts->sample_cnt = 0;
+ mod_timer(&ts->timer,
+ jiffies + msecs_to_jiffies(TSC2046_TS_SCAN_TIME));
+ }
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+/* Must be called with ts->lock held */
+static void tsc2046_ts_disable(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+
+ if (ts->disabled)
+ return;
+
+ ts->disabled = 1;
+ if (!ts->pending) {
+ ts->irq_enabled = 0;
+ disable_irq(ts->irq);
+ } else {
+ while (ts->pending) {
+ spin_unlock_irq(&ts->lock);
+ msleep(1);
+ spin_lock_irq(&ts->lock);
+ }
+ }
+}
+
+static void tsc2046_ts_enable(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+
+ if (!ts->disabled)
+ return;
+
+ ts->disabled = 0;
+ ts->irq_enabled = 1;
+ enable_irq(ts->irq);
+}
+
+#ifdef CONFIG_PM
+int tsc2046_ts_suspend(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+
+ spin_lock_irq(&ts->lock);
+ tsc2046_ts_disable(tsc);
+ spin_unlock_irq(&ts->lock);
+
+ return 0;
+}
+
+void tsc2046_ts_resume(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+
+ spin_lock_irq(&ts->lock);
+ tsc2046_ts_enable(tsc);
+ spin_unlock_irq(&ts->lock);
+}
+#endif
+
+static void tsc2046_ts_setup_spi_xfer(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+ struct spi_message *m = &ts->read_msg;
+ struct spi_transfer *x = &ts->read_xfer[1];
+
+ spi_message_init(m);
+
+ /* read and write data in one transaction */
+ x->tx_buf = &tsc2046_ts_cmd_data;
+ x->rx_buf = &ts->data;
+ x->len = 10;
+ spi_message_add_tail(x, m);
+
+ /* send another START_BYTE to (re)enable pen interrupts */
+ x++;
+ x->tx_buf = &tsc2046_ts_cmd_data[0];
+ x->len = 2;
+ spi_message_add_tail(x, m);
+
+ m->complete = tsc2046_ts_rx;
+ m->context = tsc;
+}
+
+static ssize_t tsc2046_ts_pen_down_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tsc2046 *tsc = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", is_pen_down(tsc->ts));
+}
+
+static DEVICE_ATTR(pen_down, S_IRUGO, tsc2046_ts_pen_down_show, NULL);
+
+static ssize_t tsc2046_ts_disable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tsc2046 *tsc = dev_get_drvdata(dev);
+ struct tsc2046_ts *ts = tsc->ts;
+
+ return sprintf(buf, "%u\n", ts->disabled);
+}
+
+static ssize_t tsc2046_ts_disable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct tsc2046 *tsc = dev_get_drvdata(dev);
+ struct tsc2046_ts *ts = tsc->ts;
+ char *endp;
+ int i;
+
+ i = simple_strtoul(buf, &endp, 10);
+ spin_lock_irq(&ts->lock);
+
+ if (i)
+ tsc2046_ts_disable(tsc);
+ else
+ tsc2046_ts_enable(tsc);
+
+ spin_unlock_irq(&ts->lock);
+
+ return count;
+}
+
+static DEVICE_ATTR(disable_ts, 0664, tsc2046_ts_disable_show,
+ tsc2046_ts_disable_store);
+
+int __devinit tsc2046_ts_init(struct tsc2046 *tsc,
+ struct tsc2046_platform_data *pdata)
+{
+ struct tsc2046_ts *ts;
+ struct input_dev *idev;
+ int dav_gpio, r;
+
+ if (pdata->dav_gpio < 0) {
+ dev_err(&tsc->spi->dev, "need DAV GPIO");
+ return -EINVAL;
+ }
+ dav_gpio = pdata->dav_gpio;
+
+ ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+ if (ts == NULL)
+ return -ENOMEM;
+ tsc->ts = ts;
+
+ ts->dav_gpio = dav_gpio;
+#ifdef CONFIG_ARCH_OMAP
+ r = omap_request_gpio(dav_gpio);
+ if (r < 0) {
+ dev_err(&tsc->spi->dev, "unable to get DAV GPIO");
+ goto err1;
+ }
+ omap_set_gpio_direction(dav_gpio, 1);
+ if (pdata->gpio_debounce) {
+ omap_set_gpio_debounce(tsc->gpio, 1);
+ omap_set_gpio_debounce_time(tsc->gpio, pdata->gpio_debounce);
+ }
+
+ ts->irq = OMAP_GPIO_IRQ(dav_gpio);
+#endif
+ init_timer(&ts->timer);
+ ts->timer.data = (unsigned long) tsc;
+ ts->timer.function = tsc2046_ts_timer;
+
+ spin_lock_init(&ts->lock);
+
+ ts->x_plate_ohm = pdata->ts_x_plate_ohm ? : 280;
+ ts->max_pressure= pdata->ts_max_pressure ? : MAX_12BIT;
+ ts->touch_pressure = pdata->ts_touch_pressure ? : ts->max_pressure;
+ ts->ignore_last = pdata->ts_ignore_last;
+
+ idev = input_allocate_device();
+ if (idev == NULL) {
+ r = -ENOMEM;
+ goto err2;
+ }
+ idev->name = "TSC2046 touchscreen";
+ snprintf(ts->phys, sizeof(ts->phys),
+ "%s/input-ts", tsc->spi->dev.bus_id);
+ idev->phys = ts->phys;
+
+ idev->evbit[0] = BIT(EV_ABS) | BIT(EV_KEY);
+ idev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE);
+ ts->idev = idev;
+
+ tsc2046_ts_setup_spi_xfer(tsc);
+
+ /* These parameters should perhaps be configurable? */
+ input_set_abs_params(idev, ABS_X, 0, 4096, 0, 0);
+ input_set_abs_params(idev, ABS_Y, 0, 4096, 0, 0);
+ input_set_abs_params(idev, ABS_PRESSURE, 0, 1024, 0, 0);
+
+ ts->irq_enabled = 1;
+ r = request_irq(ts->irq, tsc2046_ts_irq_handler,
+ SA_SAMPLE_RANDOM | SA_TRIGGER_FALLING,
+ "tsc2046-ts", tsc);
+ if (r < 0) {
+ dev_err(&tsc->spi->dev, "unable to get DAV IRQ");
+ goto err3;
+ }
+ set_irq_wake(ts->irq, 1);
+
+ if (device_create_file(&tsc->spi->dev, &dev_attr_pen_down) < 0)
+ goto err4;
+ if (device_create_file(&tsc->spi->dev, &dev_attr_disable_ts) < 0)
+ goto err5;
+
+ r = input_register_device(idev);
+ if (r < 0) {
+ dev_err(&tsc->spi->dev, "can't register touchscreen device\n");
+ goto err6;
+ }
+
+ /* kick off a transaction to enable pen interrupts */
+ spi_async(tsc->spi, &ts->read_msg);
+
+ return 0;
+err6:
+ device_remove_file(&tsc->spi->dev, &dev_attr_disable_ts);
+err5:
+ device_remove_file(&tsc->spi->dev, &dev_attr_pen_down);
+err4:
+ free_irq(ts->irq, tsc);
+err3:
+ input_free_device(idev);
+err2:
+#ifdef CONFIG_ARCH_OMAP
+ omap_free_gpio(dav_gpio);
+#endif
+ err1:
+ kfree(ts);
+ return r;
+}
+EXPORT_SYMBOL(tsc2046_ts_init);
+
+void __devexit tsc2046_ts_exit(struct tsc2046 *tsc)
+{
+ struct tsc2046_ts *ts = tsc->ts;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ tsc2046_ts_disable(tsc);
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ device_remove_file(&tsc->spi->dev, &dev_attr_disable_ts);
+ device_remove_file(&tsc->spi->dev, &dev_attr_pen_down);
+
+ free_irq(ts->irq, tsc);
+ input_unregister_device(ts->idev);
+
+#ifdef CONFIG_ARCH_OMAP
+ omap_free_gpio(ts->dav_gpio);
+#endif
+ kfree(ts);
+}
+EXPORT_SYMBOL(tsc2046_ts_exit);
+
+
+static int __devinit tsc2046_probe(struct spi_device *spi)
+{
+ struct tsc2046 *tsc;
+ struct tsc2046_platform_data *pdata = spi->dev.platform_data;
+ int r = -ENODEV;
+
+ dev_dbg(&spi->dev, "%s\n", __FUNCTION__);
+
+ if (!pdata) {
+ dev_dbg(&spi->dev, "no platform data?\n");
+ return -ENODEV;
+ }
+
+ tsc = kzalloc(sizeof(*tsc), GFP_KERNEL);
+ if (tsc == NULL)
+ return -ENOMEM;
+
+ dev_set_drvdata(&spi->dev, tsc);
+ tsc->spi = spi;
+ spi->dev.power.power_state = PMSG_ON;
+
+ spi->mode = SPI_MODE_1;
+ spi->bits_per_word = 16;
+
+ /* The max speed might've been defined by the board-specific
+ * struct */
+ if (!spi->max_speed_hz)
+ spi->max_speed_hz = TSC2046_HZ;
+ spi_setup(spi);
+
+ r = tsc2046_ts_init(tsc, pdata);
+ if (r)
+ goto err1;
+
+ return 0;
+ err1:
+ kfree(tsc);
+ return r;
+}
+
+static int __devexit tsc2046_remove(struct spi_device *spi)
+{
+ struct tsc2046 *tsc = dev_get_drvdata(&spi->dev);
+
+ dev_dbg(&tsc->spi->dev, "%s\n", __FUNCTION__);
+
+ tsc2046_ts_exit(tsc);
+ kfree(tsc);
+
+ return 0;
+}
+
+static struct spi_driver tsc2046_driver = {
+ .driver = {
+ .name = "tsc2046",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+ .probe = tsc2046_probe,
+ .remove = __devexit_p(tsc2046_remove),
+};
+
+static int __init tsc2046_init(void)
+{
+ printk("TSC2046 driver initializing\n");
+
+ return spi_register_driver(&tsc2046_driver);
+}
+module_init(tsc2046_init);
+
+static void __exit tsc2046_exit(void)
+{
+ spi_unregister_driver(&tsc2046_driver);
+}
+module_exit(tsc2046_exit);
+
+MODULE_AUTHOR("Kevin Hilman <khilman@mvista.com>");
+MODULE_LICENSE("GPL");
projects / linux-2.6-omap-h63xx.git / commitdiff