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path: root/drivers/input/touchscreen/pcap_ts.c
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Diffstat (limited to 'drivers/input/touchscreen/pcap_ts.c')
-rw-r--r--drivers/input/touchscreen/pcap_ts.c254
1 files changed, 254 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/pcap_ts.c b/drivers/input/touchscreen/pcap_ts.c
new file mode 100644
index 0000000000..b2da0194e0
--- /dev/null
+++ b/drivers/input/touchscreen/pcap_ts.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Motorola PCAP2 touchscreen as found in the EZX phone platform.
+ *
+ * Copyright (C) 2006 Harald Welte <laforge@openezx.org>
+ * Copyright (C) 2009 Daniel Ribeiro <drwyrm@gmail.com>
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/mfd/ezx-pcap.h>
+
+struct pcap_ts {
+ struct pcap_chip *pcap;
+ struct input_dev *input;
+ struct delayed_work work;
+ u16 x, y;
+ u16 pressure;
+ u8 read_state;
+};
+
+#define SAMPLE_DELAY 20 /* msecs */
+
+#define X_AXIS_MIN 0
+#define X_AXIS_MAX 1023
+#define Y_AXIS_MAX X_AXIS_MAX
+#define Y_AXIS_MIN X_AXIS_MIN
+#define PRESSURE_MAX X_AXIS_MAX
+#define PRESSURE_MIN X_AXIS_MIN
+
+static void pcap_ts_read_xy(void *data, u16 res[2])
+{
+ struct pcap_ts *pcap_ts = data;
+
+ switch (pcap_ts->read_state) {
+ case PCAP_ADC_TS_M_PRESSURE:
+ /* pressure reading is unreliable */
+ if (res[0] > PRESSURE_MIN && res[0] < PRESSURE_MAX)
+ pcap_ts->pressure = res[0];
+ pcap_ts->read_state = PCAP_ADC_TS_M_XY;
+ schedule_delayed_work(&pcap_ts->work, 0);
+ break;
+ case PCAP_ADC_TS_M_XY:
+ pcap_ts->y = res[0];
+ pcap_ts->x = res[1];
+ if (pcap_ts->x <= X_AXIS_MIN || pcap_ts->x >= X_AXIS_MAX ||
+ pcap_ts->y <= Y_AXIS_MIN || pcap_ts->y >= Y_AXIS_MAX) {
+ /* pen has been released */
+ input_report_abs(pcap_ts->input, ABS_PRESSURE, 0);
+ input_report_key(pcap_ts->input, BTN_TOUCH, 0);
+
+ pcap_ts->read_state = PCAP_ADC_TS_M_STANDBY;
+ schedule_delayed_work(&pcap_ts->work, 0);
+ } else {
+ /* pen is touching the screen */
+ input_report_abs(pcap_ts->input, ABS_X, pcap_ts->x);
+ input_report_abs(pcap_ts->input, ABS_Y, pcap_ts->y);
+ input_report_key(pcap_ts->input, BTN_TOUCH, 1);
+ input_report_abs(pcap_ts->input, ABS_PRESSURE,
+ pcap_ts->pressure);
+
+ /* switch back to pressure read mode */
+ pcap_ts->read_state = PCAP_ADC_TS_M_PRESSURE;
+ schedule_delayed_work(&pcap_ts->work,
+ msecs_to_jiffies(SAMPLE_DELAY));
+ }
+ input_sync(pcap_ts->input);
+ break;
+ default:
+ dev_warn(&pcap_ts->input->dev,
+ "pcap_ts: Warning, unhandled read_state %d\n",
+ pcap_ts->read_state);
+ break;
+ }
+}
+
+static void pcap_ts_work(struct work_struct *work)
+{
+ struct delayed_work *dw = to_delayed_work(work);
+ struct pcap_ts *pcap_ts = container_of(dw, struct pcap_ts, work);
+ u8 ch[2];
+
+ pcap_set_ts_bits(pcap_ts->pcap,
+ pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT);
+
+ if (pcap_ts->read_state == PCAP_ADC_TS_M_STANDBY)
+ return;
+
+ /* start adc conversion */
+ ch[0] = PCAP_ADC_CH_TS_X1;
+ ch[1] = PCAP_ADC_CH_TS_Y1;
+ pcap_adc_async(pcap_ts->pcap, PCAP_ADC_BANK_1, 0, ch,
+ pcap_ts_read_xy, pcap_ts);
+}
+
+static irqreturn_t pcap_ts_event_touch(int pirq, void *data)
+{
+ struct pcap_ts *pcap_ts = data;
+
+ if (pcap_ts->read_state == PCAP_ADC_TS_M_STANDBY) {
+ pcap_ts->read_state = PCAP_ADC_TS_M_PRESSURE;
+ schedule_delayed_work(&pcap_ts->work, 0);
+ }
+ return IRQ_HANDLED;
+}
+
+static int pcap_ts_open(struct input_dev *dev)
+{
+ struct pcap_ts *pcap_ts = input_get_drvdata(dev);
+
+ pcap_ts->read_state = PCAP_ADC_TS_M_STANDBY;
+ schedule_delayed_work(&pcap_ts->work, 0);
+
+ return 0;
+}
+
+static void pcap_ts_close(struct input_dev *dev)
+{
+ struct pcap_ts *pcap_ts = input_get_drvdata(dev);
+
+ cancel_delayed_work_sync(&pcap_ts->work);
+
+ pcap_ts->read_state = PCAP_ADC_TS_M_NONTS;
+ pcap_set_ts_bits(pcap_ts->pcap,
+ pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT);
+}
+
+static int pcap_ts_probe(struct platform_device *pdev)
+{
+ struct input_dev *input_dev;
+ struct pcap_ts *pcap_ts;
+ int err = -ENOMEM;
+
+ pcap_ts = kzalloc(sizeof(*pcap_ts), GFP_KERNEL);
+ if (!pcap_ts)
+ return err;
+
+ pcap_ts->pcap = dev_get_drvdata(pdev->dev.parent);
+ platform_set_drvdata(pdev, pcap_ts);
+
+ input_dev = input_allocate_device();
+ if (!input_dev)
+ goto fail;
+
+ INIT_DELAYED_WORK(&pcap_ts->work, pcap_ts_work);
+
+ pcap_ts->read_state = PCAP_ADC_TS_M_NONTS;
+ pcap_set_ts_bits(pcap_ts->pcap,
+ pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT);
+
+ pcap_ts->input = input_dev;
+ input_set_drvdata(input_dev, pcap_ts);
+
+ input_dev->name = "pcap-touchscreen";
+ input_dev->phys = "pcap_ts/input0";
+ input_dev->id.bustype = BUS_HOST;
+ input_dev->id.vendor = 0x0001;
+ input_dev->id.product = 0x0002;
+ input_dev->id.version = 0x0100;
+ input_dev->dev.parent = &pdev->dev;
+ input_dev->open = pcap_ts_open;
+ input_dev->close = pcap_ts_close;
+
+ 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, X_AXIS_MIN, X_AXIS_MAX, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN,
+ PRESSURE_MAX, 0, 0);
+
+ err = input_register_device(pcap_ts->input);
+ if (err)
+ goto fail_allocate;
+
+ err = request_irq(pcap_to_irq(pcap_ts->pcap, PCAP_IRQ_TS),
+ pcap_ts_event_touch, 0, "Touch Screen", pcap_ts);
+ if (err)
+ goto fail_register;
+
+ return 0;
+
+fail_register:
+ input_unregister_device(input_dev);
+ goto fail;
+fail_allocate:
+ input_free_device(input_dev);
+fail:
+ kfree(pcap_ts);
+
+ return err;
+}
+
+static int pcap_ts_remove(struct platform_device *pdev)
+{
+ struct pcap_ts *pcap_ts = platform_get_drvdata(pdev);
+
+ free_irq(pcap_to_irq(pcap_ts->pcap, PCAP_IRQ_TS), pcap_ts);
+ cancel_delayed_work_sync(&pcap_ts->work);
+
+ input_unregister_device(pcap_ts->input);
+
+ kfree(pcap_ts);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int pcap_ts_suspend(struct device *dev)
+{
+ struct pcap_ts *pcap_ts = dev_get_drvdata(dev);
+
+ pcap_set_ts_bits(pcap_ts->pcap, PCAP_ADC_TS_REF_LOWPWR);
+ return 0;
+}
+
+static int pcap_ts_resume(struct device *dev)
+{
+ struct pcap_ts *pcap_ts = dev_get_drvdata(dev);
+
+ pcap_set_ts_bits(pcap_ts->pcap,
+ pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT);
+ return 0;
+}
+
+static const struct dev_pm_ops pcap_ts_pm_ops = {
+ .suspend = pcap_ts_suspend,
+ .resume = pcap_ts_resume,
+};
+#define PCAP_TS_PM_OPS (&pcap_ts_pm_ops)
+#else
+#define PCAP_TS_PM_OPS NULL
+#endif
+
+static struct platform_driver pcap_ts_driver = {
+ .probe = pcap_ts_probe,
+ .remove = pcap_ts_remove,
+ .driver = {
+ .name = "pcap-ts",
+ .pm = PCAP_TS_PM_OPS,
+ },
+};
+module_platform_driver(pcap_ts_driver);
+
+MODULE_DESCRIPTION("Motorola PCAP2 touchscreen driver");
+MODULE_AUTHOR("Daniel Ribeiro / Harald Welte");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pcap_ts");