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-rw-r--r--drivers/mfd/ucb1x00-ts.c445
1 files changed, 445 insertions, 0 deletions
diff --git a/drivers/mfd/ucb1x00-ts.c b/drivers/mfd/ucb1x00-ts.c
new file mode 100644
index 000000000..6e1b38f9f
--- /dev/null
+++ b/drivers/mfd/ucb1x00-ts.c
@@ -0,0 +1,445 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Touchscreen driver for UCB1x00-based touchscreens
+ *
+ * Copyright (C) 2001 Russell King, All Rights Reserved.
+ * Copyright (C) 2005 Pavel Machek
+ *
+ * 21-Jan-2002 <jco@ict.es> :
+ *
+ * Added support for synchronous A/D mode. This mode is useful to
+ * avoid noise induced in the touchpanel by the LCD, provided that
+ * the UCB1x00 has a valid LCD sync signal routed to its ADCSYNC pin.
+ * It is important to note that the signal connected to the ADCSYNC
+ * pin should provide pulses even when the LCD is blanked, otherwise
+ * a pen touch needed to unblank the LCD will never be read.
+ */
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/input.h>
+#include <linux/device.h>
+#include <linux/freezer.h>
+#include <linux/slab.h>
+#include <linux/kthread.h>
+#include <linux/mfd/ucb1x00.h>
+
+#include <mach/collie.h>
+#include <asm/mach-types.h>
+
+
+
+struct ucb1x00_ts {
+ struct input_dev *idev;
+ struct ucb1x00 *ucb;
+
+ spinlock_t irq_lock;
+ unsigned irq_disabled;
+ wait_queue_head_t irq_wait;
+ struct task_struct *rtask;
+ u16 x_res;
+ u16 y_res;
+
+ unsigned int adcsync:1;
+};
+
+static int adcsync;
+
+static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
+{
+ struct input_dev *idev = ts->idev;
+
+ input_report_abs(idev, ABS_X, x);
+ input_report_abs(idev, ABS_Y, y);
+ input_report_abs(idev, ABS_PRESSURE, pressure);
+ input_report_key(idev, BTN_TOUCH, 1);
+ input_sync(idev);
+}
+
+static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
+{
+ struct input_dev *idev = ts->idev;
+
+ input_report_abs(idev, ABS_PRESSURE, 0);
+ input_report_key(idev, BTN_TOUCH, 0);
+ input_sync(idev);
+}
+
+/*
+ * Switch to interrupt mode.
+ */
+static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
+{
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
+ UCB_TS_CR_MODE_INT);
+}
+
+/*
+ * Switch to pressure mode, and read pressure. We don't need to wait
+ * here, since both plates are being driven.
+ */
+static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
+{
+ if (machine_is_collie()) {
+ ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
+ UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
+
+ udelay(55);
+
+ return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
+ } else {
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+
+ return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
+ }
+}
+
+/*
+ * Switch to X position mode and measure Y plate. We switch the plate
+ * configuration in pressure mode, then switch to position mode. This
+ * gives a faster response time. Even so, we need to wait about 55us
+ * for things to stabilise.
+ */
+static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
+{
+ if (machine_is_collie())
+ ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
+ else {
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ }
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
+
+ udelay(55);
+
+ return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
+}
+
+/*
+ * Switch to Y position mode and measure X plate. We switch the plate
+ * configuration in pressure mode, then switch to position mode. This
+ * gives a faster response time. Even so, we need to wait about 55us
+ * for things to stabilise.
+ */
+static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
+{
+ if (machine_is_collie())
+ ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
+ else {
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ }
+
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
+
+ udelay(55);
+
+ return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
+}
+
+/*
+ * Switch to X plate resistance mode. Set MX to ground, PX to
+ * supply. Measure current.
+ */
+static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
+{
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
+}
+
+/*
+ * Switch to Y plate resistance mode. Set MY to ground, PY to
+ * supply. Measure current.
+ */
+static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
+{
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
+}
+
+static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
+{
+ unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
+
+ if (machine_is_collie())
+ return (!(val & (UCB_TS_CR_TSPX_LOW)));
+ else
+ return (val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW));
+}
+
+/*
+ * This is a RT kernel thread that handles the ADC accesses
+ * (mainly so we can use semaphores in the UCB1200 core code
+ * to serialise accesses to the ADC).
+ */
+static int ucb1x00_thread(void *_ts)
+{
+ struct ucb1x00_ts *ts = _ts;
+ DECLARE_WAITQUEUE(wait, current);
+ bool frozen, ignore = false;
+ int valid = 0;
+
+ set_freezable();
+ add_wait_queue(&ts->irq_wait, &wait);
+ while (!kthread_freezable_should_stop(&frozen)) {
+ unsigned int x, y, p;
+ signed long timeout;
+
+ if (frozen)
+ ignore = true;
+
+ ucb1x00_adc_enable(ts->ucb);
+
+ x = ucb1x00_ts_read_xpos(ts);
+ y = ucb1x00_ts_read_ypos(ts);
+ p = ucb1x00_ts_read_pressure(ts);
+
+ /*
+ * Switch back to interrupt mode.
+ */
+ ucb1x00_ts_mode_int(ts);
+ ucb1x00_adc_disable(ts->ucb);
+
+ msleep(10);
+
+ ucb1x00_enable(ts->ucb);
+
+
+ if (ucb1x00_ts_pen_down(ts)) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ spin_lock_irq(&ts->irq_lock);
+ if (ts->irq_disabled) {
+ ts->irq_disabled = 0;
+ enable_irq(ts->ucb->irq_base + UCB_IRQ_TSPX);
+ }
+ spin_unlock_irq(&ts->irq_lock);
+ ucb1x00_disable(ts->ucb);
+
+ /*
+ * If we spat out a valid sample set last time,
+ * spit out a "pen off" sample here.
+ */
+ if (valid) {
+ ucb1x00_ts_event_release(ts);
+ valid = 0;
+ }
+
+ timeout = MAX_SCHEDULE_TIMEOUT;
+ } else {
+ ucb1x00_disable(ts->ucb);
+
+ /*
+ * Filtering is policy. Policy belongs in user
+ * space. We therefore leave it to user space
+ * to do any filtering they please.
+ */
+ if (!ignore) {
+ ucb1x00_ts_evt_add(ts, p, x, y);
+ valid = 1;
+ }
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ timeout = HZ / 100;
+ }
+
+ schedule_timeout(timeout);
+ }
+
+ remove_wait_queue(&ts->irq_wait, &wait);
+
+ ts->rtask = NULL;
+ return 0;
+}
+
+/*
+ * We only detect touch screen _touches_ with this interrupt
+ * handler, and even then we just schedule our task.
+ */
+static irqreturn_t ucb1x00_ts_irq(int irq, void *id)
+{
+ struct ucb1x00_ts *ts = id;
+
+ spin_lock(&ts->irq_lock);
+ ts->irq_disabled = 1;
+ disable_irq_nosync(ts->ucb->irq_base + UCB_IRQ_TSPX);
+ spin_unlock(&ts->irq_lock);
+ wake_up(&ts->irq_wait);
+
+ return IRQ_HANDLED;
+}
+
+static int ucb1x00_ts_open(struct input_dev *idev)
+{
+ struct ucb1x00_ts *ts = input_get_drvdata(idev);
+ unsigned long flags = 0;
+ int ret = 0;
+
+ BUG_ON(ts->rtask);
+
+ if (machine_is_collie())
+ flags = IRQF_TRIGGER_RISING;
+ else
+ flags = IRQF_TRIGGER_FALLING;
+
+ ts->irq_disabled = 0;
+
+ init_waitqueue_head(&ts->irq_wait);
+ ret = request_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ucb1x00_ts_irq,
+ flags, "ucb1x00-ts", ts);
+ if (ret < 0)
+ goto out;
+
+ /*
+ * If we do this at all, we should allow the user to
+ * measure and read the X and Y resistance at any time.
+ */
+ ucb1x00_adc_enable(ts->ucb);
+ ts->x_res = ucb1x00_ts_read_xres(ts);
+ ts->y_res = ucb1x00_ts_read_yres(ts);
+ ucb1x00_adc_disable(ts->ucb);
+
+ ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
+ if (!IS_ERR(ts->rtask)) {
+ ret = 0;
+ } else {
+ free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
+ ts->rtask = NULL;
+ ret = -EFAULT;
+ }
+
+ out:
+ return ret;
+}
+
+/*
+ * Release touchscreen resources. Disable IRQs.
+ */
+static void ucb1x00_ts_close(struct input_dev *idev)
+{
+ struct ucb1x00_ts *ts = input_get_drvdata(idev);
+
+ if (ts->rtask)
+ kthread_stop(ts->rtask);
+
+ ucb1x00_enable(ts->ucb);
+ free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
+ ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
+ ucb1x00_disable(ts->ucb);
+}
+
+
+/*
+ * Initialisation.
+ */
+static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
+{
+ struct ucb1x00_ts *ts;
+ struct input_dev *idev;
+ int err;
+
+ ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
+ idev = input_allocate_device();
+ if (!ts || !idev) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ ts->ucb = dev->ucb;
+ ts->idev = idev;
+ ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;
+ spin_lock_init(&ts->irq_lock);
+
+ idev->name = "Touchscreen panel";
+ idev->id.product = ts->ucb->id;
+ idev->open = ucb1x00_ts_open;
+ idev->close = ucb1x00_ts_close;
+ idev->dev.parent = &ts->ucb->dev;
+
+ idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
+ idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ input_set_drvdata(idev, ts);
+
+ ucb1x00_adc_enable(ts->ucb);
+ ts->x_res = ucb1x00_ts_read_xres(ts);
+ ts->y_res = ucb1x00_ts_read_yres(ts);
+ ucb1x00_adc_disable(ts->ucb);
+
+ input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
+ input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
+ input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);
+
+ err = input_register_device(idev);
+ if (err)
+ goto fail;
+
+ dev->priv = ts;
+
+ return 0;
+
+ fail:
+ input_free_device(idev);
+ kfree(ts);
+ return err;
+}
+
+static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
+{
+ struct ucb1x00_ts *ts = dev->priv;
+
+ input_unregister_device(ts->idev);
+ kfree(ts);
+}
+
+static struct ucb1x00_driver ucb1x00_ts_driver = {
+ .add = ucb1x00_ts_add,
+ .remove = ucb1x00_ts_remove,
+};
+
+static int __init ucb1x00_ts_init(void)
+{
+ return ucb1x00_register_driver(&ucb1x00_ts_driver);
+}
+
+static void __exit ucb1x00_ts_exit(void)
+{
+ ucb1x00_unregister_driver(&ucb1x00_ts_driver);
+}
+
+module_param(adcsync, int, 0444);
+module_init(ucb1x00_ts_init);
+module_exit(ucb1x00_ts_exit);
+
+MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
+MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 21:50:12 +0000