// 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 * 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 #include #include #include #include #include #include #include #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");