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-rw-r--r--drivers/input/touchscreen/ucb1400_ts.c458
1 files changed, 458 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ucb1400_ts.c b/drivers/input/touchscreen/ucb1400_ts.c
new file mode 100644
index 000000000..dfd3b3559
--- /dev/null
+++ b/drivers/input/touchscreen/ucb1400_ts.c
@@ -0,0 +1,458 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Philips UCB1400 touchscreen driver
+ *
+ * Author: Nicolas Pitre
+ * Created: September 25, 2006
+ * Copyright: MontaVista Software, Inc.
+ *
+ * Spliting done by: Marek Vasut <marek.vasut@gmail.com>
+ * If something doesn't work and it worked before spliting, e-mail me,
+ * dont bother Nicolas please ;-)
+ *
+ * This code is heavily based on ucb1x00-*.c copyrighted by Russell King
+ * covering the UCB1100, UCB1200 and UCB1300.. Support for the UCB1400 has
+ * been made separate from ucb1x00-core/ucb1x00-ts on Russell's request.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/input.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/ucb1400.h>
+
+#define UCB1400_TS_POLL_PERIOD 10 /* ms */
+
+static bool adcsync;
+static int ts_delay = 55; /* us */
+static int ts_delay_pressure; /* us */
+
+/* Switch to interrupt mode. */
+static void ucb1400_ts_mode_int(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, 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 unsigned int ucb1400_ts_read_pressure(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, 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);
+
+ udelay(ts_delay_pressure);
+
+ return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPY, 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 unsigned int ucb1400_ts_read_xpos(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
+
+ udelay(ts_delay);
+
+ return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPY, 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 int ucb1400_ts_read_ypos(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
+
+ udelay(ts_delay);
+
+ return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPX, adcsync);
+}
+
+/*
+ * Switch to X plate resistance mode. Set MX to ground, PX to
+ * supply. Measure current.
+ */
+static unsigned int ucb1400_ts_read_xres(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ return ucb1400_adc_read(ucb->ac97, 0, adcsync);
+}
+
+/*
+ * Switch to Y plate resistance mode. Set MY to ground, PY to
+ * supply. Measure current.
+ */
+static unsigned int ucb1400_ts_read_yres(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
+ UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
+ UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
+ return ucb1400_adc_read(ucb->ac97, 0, adcsync);
+}
+
+static int ucb1400_ts_pen_up(struct ucb1400_ts *ucb)
+{
+ unsigned short val = ucb1400_reg_read(ucb->ac97, UCB_TS_CR);
+
+ return val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW);
+}
+
+static void ucb1400_ts_irq_enable(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, UCB_IE_TSPX);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, UCB_IE_TSPX);
+}
+
+static void ucb1400_ts_irq_disable(struct ucb1400_ts *ucb)
+{
+ ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, 0);
+}
+
+static void ucb1400_ts_report_event(struct input_dev *idev, u16 pressure, u16 x, u16 y)
+{
+ 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 void ucb1400_ts_event_release(struct input_dev *idev)
+{
+ input_report_abs(idev, ABS_PRESSURE, 0);
+ input_report_key(idev, BTN_TOUCH, 0);
+ input_sync(idev);
+}
+
+static void ucb1400_clear_pending_irq(struct ucb1400_ts *ucb)
+{
+ unsigned int isr;
+
+ isr = ucb1400_reg_read(ucb->ac97, UCB_IE_STATUS);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, isr);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
+
+ if (isr & UCB_IE_TSPX)
+ ucb1400_ts_irq_disable(ucb);
+ else
+ dev_dbg(&ucb->ts_idev->dev,
+ "ucb1400: unexpected IE_STATUS = %#x\n", isr);
+}
+
+/*
+ * A restriction with interrupts exists when using the ucb1400, as
+ * the codec read/write routines may sleep while waiting for codec
+ * access completion and uses semaphores for access control to the
+ * AC97 bus. Therefore the driver is forced to use threaded interrupt
+ * handler.
+ */
+static irqreturn_t ucb1400_irq(int irqnr, void *devid)
+{
+ struct ucb1400_ts *ucb = devid;
+ unsigned int x, y, p;
+
+ if (unlikely(irqnr != ucb->irq))
+ return IRQ_NONE;
+
+ ucb1400_clear_pending_irq(ucb);
+
+ /* Start with a small delay before checking pendown state */
+ msleep(UCB1400_TS_POLL_PERIOD);
+
+ while (!ucb->stopped && !ucb1400_ts_pen_up(ucb)) {
+ ucb1400_adc_enable(ucb->ac97);
+ x = ucb1400_ts_read_xpos(ucb);
+ y = ucb1400_ts_read_ypos(ucb);
+ p = ucb1400_ts_read_pressure(ucb);
+ ucb1400_adc_disable(ucb->ac97);
+
+ ucb1400_ts_report_event(ucb->ts_idev, p, x, y);
+
+ wait_event_timeout(ucb->ts_wait, ucb->stopped,
+ msecs_to_jiffies(UCB1400_TS_POLL_PERIOD));
+ }
+
+ ucb1400_ts_event_release(ucb->ts_idev);
+
+ if (!ucb->stopped) {
+ /* Switch back to interrupt mode. */
+ ucb1400_ts_mode_int(ucb);
+ ucb1400_ts_irq_enable(ucb);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void ucb1400_ts_stop(struct ucb1400_ts *ucb)
+{
+ /* Signal IRQ thread to stop polling and disable the handler. */
+ ucb->stopped = true;
+ mb();
+ wake_up(&ucb->ts_wait);
+ disable_irq(ucb->irq);
+
+ ucb1400_ts_irq_disable(ucb);
+ ucb1400_reg_write(ucb->ac97, UCB_TS_CR, 0);
+}
+
+/* Must be called with ts->lock held */
+static void ucb1400_ts_start(struct ucb1400_ts *ucb)
+{
+ /* Tell IRQ thread that it may poll the device. */
+ ucb->stopped = false;
+ mb();
+
+ ucb1400_ts_mode_int(ucb);
+ ucb1400_ts_irq_enable(ucb);
+
+ enable_irq(ucb->irq);
+}
+
+static int ucb1400_ts_open(struct input_dev *idev)
+{
+ struct ucb1400_ts *ucb = input_get_drvdata(idev);
+
+ ucb1400_ts_start(ucb);
+
+ return 0;
+}
+
+static void ucb1400_ts_close(struct input_dev *idev)
+{
+ struct ucb1400_ts *ucb = input_get_drvdata(idev);
+
+ ucb1400_ts_stop(ucb);
+}
+
+#ifndef NO_IRQ
+#define NO_IRQ 0
+#endif
+
+/*
+ * Try to probe our interrupt, rather than relying on lots of
+ * hard-coded machine dependencies.
+ */
+static int ucb1400_ts_detect_irq(struct ucb1400_ts *ucb,
+ struct platform_device *pdev)
+{
+ unsigned long mask, timeout;
+
+ mask = probe_irq_on();
+
+ /* Enable the ADC interrupt. */
+ ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, UCB_IE_ADC);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, UCB_IE_ADC);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
+
+ /* Cause an ADC interrupt. */
+ ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA);
+ ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
+
+ /* Wait for the conversion to complete. */
+ timeout = jiffies + HZ/2;
+ while (!(ucb1400_reg_read(ucb->ac97, UCB_ADC_DATA) &
+ UCB_ADC_DAT_VALID)) {
+ cpu_relax();
+ if (time_after(jiffies, timeout)) {
+ dev_err(&pdev->dev, "timed out in IRQ probe\n");
+ probe_irq_off(mask);
+ return -ENODEV;
+ }
+ }
+ ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, 0);
+
+ /* Disable and clear interrupt. */
+ ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, 0);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, 0);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
+ ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
+
+ /* Read triggered interrupt. */
+ ucb->irq = probe_irq_off(mask);
+ if (ucb->irq < 0 || ucb->irq == NO_IRQ)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int ucb1400_ts_probe(struct platform_device *pdev)
+{
+ struct ucb1400_ts *ucb = dev_get_platdata(&pdev->dev);
+ int error, x_res, y_res;
+ u16 fcsr;
+
+ ucb->ts_idev = input_allocate_device();
+ if (!ucb->ts_idev) {
+ error = -ENOMEM;
+ goto err;
+ }
+
+ /* Only in case the IRQ line wasn't supplied, try detecting it */
+ if (ucb->irq < 0) {
+ error = ucb1400_ts_detect_irq(ucb, pdev);
+ if (error) {
+ dev_err(&pdev->dev, "IRQ probe failed\n");
+ goto err_free_devs;
+ }
+ }
+ dev_dbg(&pdev->dev, "found IRQ %d\n", ucb->irq);
+
+ init_waitqueue_head(&ucb->ts_wait);
+
+ input_set_drvdata(ucb->ts_idev, ucb);
+
+ ucb->ts_idev->dev.parent = &pdev->dev;
+ ucb->ts_idev->name = "UCB1400 touchscreen interface";
+ ucb->ts_idev->id.vendor = ucb1400_reg_read(ucb->ac97,
+ AC97_VENDOR_ID1);
+ ucb->ts_idev->id.product = ucb->id;
+ ucb->ts_idev->open = ucb1400_ts_open;
+ ucb->ts_idev->close = ucb1400_ts_close;
+ ucb->ts_idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
+ ucb->ts_idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ /*
+ * Enable ADC filter to prevent horrible jitter on Colibri.
+ * This also further reduces jitter on boards where ADCSYNC
+ * pin is connected.
+ */
+ fcsr = ucb1400_reg_read(ucb->ac97, UCB_FCSR);
+ ucb1400_reg_write(ucb->ac97, UCB_FCSR, fcsr | UCB_FCSR_AVE);
+
+ ucb1400_adc_enable(ucb->ac97);
+ x_res = ucb1400_ts_read_xres(ucb);
+ y_res = ucb1400_ts_read_yres(ucb);
+ ucb1400_adc_disable(ucb->ac97);
+ dev_dbg(&pdev->dev, "x/y = %d/%d\n", x_res, y_res);
+
+ input_set_abs_params(ucb->ts_idev, ABS_X, 0, x_res, 0, 0);
+ input_set_abs_params(ucb->ts_idev, ABS_Y, 0, y_res, 0, 0);
+ input_set_abs_params(ucb->ts_idev, ABS_PRESSURE, 0, 0, 0, 0);
+
+ ucb1400_ts_stop(ucb);
+
+ error = request_threaded_irq(ucb->irq, NULL, ucb1400_irq,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "UCB1400", ucb);
+ if (error) {
+ dev_err(&pdev->dev,
+ "unable to grab irq%d: %d\n", ucb->irq, error);
+ goto err_free_devs;
+ }
+
+ error = input_register_device(ucb->ts_idev);
+ if (error)
+ goto err_free_irq;
+
+ return 0;
+
+err_free_irq:
+ free_irq(ucb->irq, ucb);
+err_free_devs:
+ input_free_device(ucb->ts_idev);
+err:
+ return error;
+}
+
+static int ucb1400_ts_remove(struct platform_device *pdev)
+{
+ struct ucb1400_ts *ucb = dev_get_platdata(&pdev->dev);
+
+ free_irq(ucb->irq, ucb);
+ input_unregister_device(ucb->ts_idev);
+
+ return 0;
+}
+
+static int __maybe_unused ucb1400_ts_suspend(struct device *dev)
+{
+ struct ucb1400_ts *ucb = dev_get_platdata(dev);
+ struct input_dev *idev = ucb->ts_idev;
+
+ mutex_lock(&idev->mutex);
+
+ if (input_device_enabled(idev))
+ ucb1400_ts_stop(ucb);
+
+ mutex_unlock(&idev->mutex);
+ return 0;
+}
+
+static int __maybe_unused ucb1400_ts_resume(struct device *dev)
+{
+ struct ucb1400_ts *ucb = dev_get_platdata(dev);
+ struct input_dev *idev = ucb->ts_idev;
+
+ mutex_lock(&idev->mutex);
+
+ if (input_device_enabled(idev))
+ ucb1400_ts_start(ucb);
+
+ mutex_unlock(&idev->mutex);
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(ucb1400_ts_pm_ops,
+ ucb1400_ts_suspend, ucb1400_ts_resume);
+
+static struct platform_driver ucb1400_ts_driver = {
+ .probe = ucb1400_ts_probe,
+ .remove = ucb1400_ts_remove,
+ .driver = {
+ .name = "ucb1400_ts",
+ .pm = &ucb1400_ts_pm_ops,
+ },
+};
+module_platform_driver(ucb1400_ts_driver);
+
+module_param(adcsync, bool, 0444);
+MODULE_PARM_DESC(adcsync, "Synchronize touch readings with ADCSYNC pin.");
+
+module_param(ts_delay, int, 0444);
+MODULE_PARM_DESC(ts_delay, "Delay between panel setup and"
+ " position read. Default = 55us.");
+
+module_param(ts_delay_pressure, int, 0444);
+MODULE_PARM_DESC(ts_delay_pressure,
+ "delay between panel setup and pressure read."
+ " Default = 0us.");
+
+MODULE_DESCRIPTION("Philips UCB1400 touchscreen driver");
+MODULE_LICENSE("GPL");