diff options
Diffstat (limited to 'drivers/input/touchscreen/pcap_ts.c')
| -rw-r--r-- | drivers/input/touchscreen/pcap_ts.c | 254 |
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"); |