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path: root/drivers/input/touchscreen/mxc_ts.c
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Diffstat (limited to 'drivers/input/touchscreen/mxc_ts.c')
-rw-r--r--drivers/input/touchscreen/mxc_ts.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/mxc_ts.c b/drivers/input/touchscreen/mxc_ts.c
new file mode 100644
index 000000000000..b354d81c5465
--- /dev/null
+++ b/drivers/input/touchscreen/mxc_ts.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+/*!
+ * @file mxc_ts.c
+ *
+ * @brief Driver for the Freescale Semiconductor MXC touchscreen.
+ *
+ * The touchscreen driver is designed as a standard input driver which is a
+ * wrapper over low level PMIC driver. Most of the hardware configuration and
+ * touchscreen functionality is implemented in the low level PMIC driver. During
+ * initialization, this driver creates a kernel thread. This thread then calls
+ * PMIC driver to obtain touchscreen values continously. These values are then
+ * passed to the input susbsystem.
+ *
+ * @ingroup touchscreen
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/input.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#include <linux/pmic_external.h>
+#include <linux/pmic_adc.h>
+
+#define MXC_TS_NAME "mxc_ts"
+
+static struct input_dev *mxc_inputdev = NULL;
+static u32 input_ts_installed;
+
+static int ts_thread(void *arg)
+{
+ t_touch_screen ts_sample;
+ s32 wait = 0;
+
+ daemonize("mxc_ts");
+ while (input_ts_installed) {
+ try_to_freeze();
+ memset(&ts_sample, 0, sizeof(t_touch_screen));
+ if (0 != pmic_adc_get_touch_sample(&ts_sample, !wait))
+ continue;
+ if (!(ts_sample.contact_resistance || wait))
+ continue;
+
+ input_report_abs(mxc_inputdev, ABS_X, ts_sample.x_position);
+ input_report_abs(mxc_inputdev, ABS_Y, ts_sample.y_position);
+ input_report_abs(mxc_inputdev, ABS_PRESSURE,
+ ts_sample.contact_resistance);
+ input_sync(mxc_inputdev);
+
+ wait = ts_sample.contact_resistance;
+ msleep(20);
+ }
+
+ return 0;
+}
+
+static int __init mxc_ts_init(void)
+{
+ int retval;
+
+ if (!is_pmic_adc_ready())
+ return -ENODEV;
+
+ mxc_inputdev = input_allocate_device();
+ if (!mxc_inputdev) {
+ printk(KERN_ERR
+ "mxc_ts_init: not enough memory for input device\n");
+ return -ENOMEM;
+ }
+
+ mxc_inputdev->name = MXC_TS_NAME;
+ mxc_inputdev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ mxc_inputdev->keybit[BIT_WORD(BTN_TOUCH)] |= BIT_MASK(BTN_TOUCH);
+ mxc_inputdev->absbit[0] =
+ BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) | BIT_MASK(ABS_PRESSURE);
+ retval = input_register_device(mxc_inputdev);
+ if (retval < 0) {
+ input_free_device(mxc_inputdev);
+ return retval;
+ }
+
+ input_ts_installed = 1;
+ kernel_thread(ts_thread, NULL, CLONE_VM | CLONE_FS);
+ printk("mxc input touchscreen loaded\n");
+ return 0;
+}
+
+static void __exit mxc_ts_exit(void)
+{
+ input_ts_installed = 0;
+ input_unregister_device(mxc_inputdev);
+
+ if (mxc_inputdev) {
+ input_free_device(mxc_inputdev);
+ mxc_inputdev = NULL;
+ }
+}
+
+late_initcall(mxc_ts_init);
+module_exit(mxc_ts_exit);
+
+MODULE_DESCRIPTION("MXC input touchscreen driver");
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_LICENSE("GPL");