Extra omap code in linux-omap tree

[linux-2.6-omap-h63xx.git] / drivers / input / touchscreen / tsc210x_ts.c

diff --git a/drivers/input/touchscreen/tsc210x_ts.c b/drivers/input/touchscreen/tsc210x_ts.c
new file mode 100644 (file)
index 0000000..5828b6d
--- /dev/null
+++ b/drivers/input/touchscreen/tsc210x_ts.c
@@ -0,0 +1,160 @@
+/*
+ * tsc210x_ts.c - touchscreen input device for TI TSC210x chips
+ *
+ * Copyright (c) 2006-2007 Andrzej Zaborowski  <balrog@zabor.org>
+ *
+ * This package is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This package is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this package; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+
+#include <linux/spi/tsc210x.h>
+
+
+/*
+ * The sensor ADC on tsc210x chips is most often used with the smart
+ * touchscreen controller.   Those controllers can be made to improve
+ * sample quality directly by multi-sampling and by taking the mean or
+ * median of various numbers of samples.  They also take X, Y, and
+ * pressure measurements automatically, so this driver has relatively
+ * little to do.
+ *
+ * There are a few chips in this family that don't have quite the same
+ * touchscreen interface, e.g. no "median" mode.
+ */
+
+static void tsc210x_touch(void *context, int touching)
+{
+       struct input_dev *dev = context;
+
+       if (!touching) {
+               input_report_abs(dev, ABS_X, 0);
+               input_report_abs(dev, ABS_Y, 0);
+               input_report_abs(dev, ABS_PRESSURE, 0);
+               input_sync(dev);
+       }
+
+       input_report_key(dev, BTN_TOUCH, touching);
+}
+
+static void tsc210x_coords(void *context, int x, int y, int z1, int z2)
+{
+       struct input_dev *dev = context;
+       int p;
+
+       /* Calculate the touch resistance a la equation #1 */
+       if (z1 != 0)
+               p = x * (z2 - z1) / (z1 << 4);
+       else
+               p = 1;
+
+       input_report_abs(dev, ABS_X, x);
+       input_report_abs(dev, ABS_Y, y);
+       input_report_abs(dev, ABS_PRESSURE, p);
+       input_sync(dev);
+}
+
+static int tsc210x_ts_probe(struct platform_device *pdev)
+{
+       int status;
+       struct input_dev *dev;
+
+       dev = input_allocate_device();
+       if (!dev)
+               return -ENOMEM;
+
+       status = tsc210x_touch_cb(pdev->dev.parent, tsc210x_touch, dev);
+       if (status) {
+               input_free_device(dev);
+               return status;
+       }
+
+       status = tsc210x_coords_cb(pdev->dev.parent, tsc210x_coords, dev);
+       if (status) {
+               tsc210x_touch_cb(pdev->dev.parent, NULL, NULL);
+               input_free_device(dev);
+               return status;
+       }
+
+       dev->name = "TSC210x Touchscreen";
+       dev->dev.parent = &pdev->dev;
+       dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
+       dev->keybit[BIT_WORD(BTN_TOUCH)] |= BIT_MASK(BTN_TOUCH);
+       dev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE);
+       dev->phys = "tsc210x/input0";
+       dev->id.bustype = BUS_HOST;
+       dev->id.vendor = 0x0001;
+       dev->id.product = 0x2100;
+       dev->id.version = 0x0001;
+
+       status = input_register_device(dev);
+       if (status) {
+               tsc210x_coords_cb(pdev->dev.parent, NULL, NULL);
+               tsc210x_touch_cb(pdev->dev.parent, NULL, NULL);
+               input_free_device(dev);
+               return status;
+       }
+
+       platform_set_drvdata(pdev, dev);
+       printk(KERN_INFO "TSC210x touchscreen initialised\n");
+       return 0;
+}
+
+static int __exit tsc210x_ts_remove(struct platform_device *pdev)
+{
+       struct input_dev *dev = platform_get_drvdata(pdev);
+
+       tsc210x_touch_cb(pdev->dev.parent, NULL, NULL);
+       tsc210x_coords_cb(pdev->dev.parent, NULL, NULL);
+       platform_set_drvdata(pdev, NULL);
+       input_unregister_device(dev);
+       input_free_device(dev);
+
+       return 0;
+}
+
+static struct platform_driver tsc210x_ts_driver = {
+       .probe          = tsc210x_ts_probe,
+       .remove         = __exit_p(tsc210x_ts_remove),
+       /* Nothing to do on suspend/resume */
+       .driver         = {
+               .name   = "tsc210x-ts",
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init tsc210x_ts_init(void)
+{
+       /* can't use driver_probe() here since the parent device
+        * gets registered "late"
+        */
+       return platform_driver_register(&tsc210x_ts_driver);
+}
+module_init(tsc210x_ts_init);
+
+static void __exit tsc210x_ts_exit(void)
+{
+       platform_driver_unregister(&tsc210x_ts_driver);
+}
+module_exit(tsc210x_ts_exit);
+
+MODULE_AUTHOR("Andrzej Zaborowski");
+MODULE_DESCRIPTION("Touchscreen input driver for TI TSC2101/2102.");
+MODULE_LICENSE("GPL");