diff options
Diffstat (limited to 'drivers/input/touchscreen/ucb1400_ts.c')
| -rw-r--r-- | drivers/input/touchscreen/ucb1400_ts.c | 460 |
1 files changed, 460 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..807d39e18 --- /dev/null +++ b/drivers/input/touchscreen/ucb1400_ts.c @@ -0,0 +1,460 @@ +// 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; + bool penup; + + 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 && !(penup = 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 (idev->users) + 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 (idev->users) + 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"); |