| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Touchscreen driver for Dialog Semiconductor DA9034 |
| * |
| * Copyright (C) 2006-2008 Marvell International Ltd. |
| * Fengwei Yin <fengwei.yin@marvell.com> |
| * Bin Yang <bin.yang@marvell.com> |
| * Eric Miao <eric.miao@marvell.com> |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/delay.h> |
| #include <linux/platform_device.h> |
| #include <linux/input.h> |
| #include <linux/workqueue.h> |
| #include <linux/mfd/da903x.h> |
| #include <linux/slab.h> |
| |
| #define DA9034_MANUAL_CTRL 0x50 |
| #define DA9034_LDO_ADC_EN (1 << 4) |
| |
| #define DA9034_AUTO_CTRL1 0x51 |
| |
| #define DA9034_AUTO_CTRL2 0x52 |
| #define DA9034_AUTO_TSI_EN (1 << 3) |
| #define DA9034_PEN_DETECT (1 << 4) |
| |
| #define DA9034_TSI_CTRL1 0x53 |
| #define DA9034_TSI_CTRL2 0x54 |
| #define DA9034_TSI_X_MSB 0x6c |
| #define DA9034_TSI_Y_MSB 0x6d |
| #define DA9034_TSI_XY_LSB 0x6e |
| |
| enum { |
| STATE_IDLE, /* wait for pendown */ |
| STATE_BUSY, /* TSI busy sampling */ |
| STATE_STOP, /* sample available */ |
| STATE_WAIT, /* Wait to start next sample */ |
| }; |
| |
| enum { |
| EVENT_PEN_DOWN, |
| EVENT_PEN_UP, |
| EVENT_TSI_READY, |
| EVENT_TIMEDOUT, |
| }; |
| |
| struct da9034_touch { |
| struct device *da9034_dev; |
| struct input_dev *input_dev; |
| |
| struct delayed_work tsi_work; |
| struct notifier_block notifier; |
| |
| int state; |
| |
| int interval_ms; |
| int x_inverted; |
| int y_inverted; |
| |
| int last_x; |
| int last_y; |
| }; |
| |
| static inline int is_pen_down(struct da9034_touch *touch) |
| { |
| return da903x_query_status(touch->da9034_dev, DA9034_STATUS_PEN_DOWN); |
| } |
| |
| static inline int detect_pen_down(struct da9034_touch *touch, int on) |
| { |
| if (on) |
| return da903x_set_bits(touch->da9034_dev, |
| DA9034_AUTO_CTRL2, DA9034_PEN_DETECT); |
| else |
| return da903x_clr_bits(touch->da9034_dev, |
| DA9034_AUTO_CTRL2, DA9034_PEN_DETECT); |
| } |
| |
| static int read_tsi(struct da9034_touch *touch) |
| { |
| uint8_t _x, _y, _v; |
| int ret; |
| |
| ret = da903x_read(touch->da9034_dev, DA9034_TSI_X_MSB, &_x); |
| if (ret) |
| return ret; |
| |
| ret = da903x_read(touch->da9034_dev, DA9034_TSI_Y_MSB, &_y); |
| if (ret) |
| return ret; |
| |
| ret = da903x_read(touch->da9034_dev, DA9034_TSI_XY_LSB, &_v); |
| if (ret) |
| return ret; |
| |
| touch->last_x = ((_x << 2) & 0x3fc) | (_v & 0x3); |
| touch->last_y = ((_y << 2) & 0x3fc) | ((_v & 0xc) >> 2); |
| |
| return 0; |
| } |
| |
| static inline int start_tsi(struct da9034_touch *touch) |
| { |
| return da903x_set_bits(touch->da9034_dev, |
| DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN); |
| } |
| |
| static inline int stop_tsi(struct da9034_touch *touch) |
| { |
| return da903x_clr_bits(touch->da9034_dev, |
| DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN); |
| } |
| |
| static inline void report_pen_down(struct da9034_touch *touch) |
| { |
| int x = touch->last_x; |
| int y = touch->last_y; |
| |
| x &= 0xfff; |
| if (touch->x_inverted) |
| x = 1024 - x; |
| y &= 0xfff; |
| if (touch->y_inverted) |
| y = 1024 - y; |
| |
| input_report_abs(touch->input_dev, ABS_X, x); |
| input_report_abs(touch->input_dev, ABS_Y, y); |
| input_report_key(touch->input_dev, BTN_TOUCH, 1); |
| |
| input_sync(touch->input_dev); |
| } |
| |
| static inline void report_pen_up(struct da9034_touch *touch) |
| { |
| input_report_key(touch->input_dev, BTN_TOUCH, 0); |
| input_sync(touch->input_dev); |
| } |
| |
| static void da9034_event_handler(struct da9034_touch *touch, int event) |
| { |
| int err; |
| |
| switch (touch->state) { |
| case STATE_IDLE: |
| if (event != EVENT_PEN_DOWN) |
| break; |
| |
| /* Enable auto measurement of the TSI, this will |
| * automatically disable pen down detection |
| */ |
| err = start_tsi(touch); |
| if (err) |
| goto err_reset; |
| |
| touch->state = STATE_BUSY; |
| break; |
| |
| case STATE_BUSY: |
| if (event != EVENT_TSI_READY) |
| break; |
| |
| err = read_tsi(touch); |
| if (err) |
| goto err_reset; |
| |
| /* Disable auto measurement of the TSI, so that |
| * pen down status will be available |
| */ |
| err = stop_tsi(touch); |
| if (err) |
| goto err_reset; |
| |
| touch->state = STATE_STOP; |
| |
| /* FIXME: PEN_{UP/DOWN} events are expected to be |
| * available by stopping TSI, but this is found not |
| * always true, delay and simulate such an event |
| * here is more reliable |
| */ |
| mdelay(1); |
| da9034_event_handler(touch, |
| is_pen_down(touch) ? EVENT_PEN_DOWN : |
| EVENT_PEN_UP); |
| break; |
| |
| case STATE_STOP: |
| if (event == EVENT_PEN_DOWN) { |
| report_pen_down(touch); |
| schedule_delayed_work(&touch->tsi_work, |
| msecs_to_jiffies(touch->interval_ms)); |
| touch->state = STATE_WAIT; |
| } |
| |
| if (event == EVENT_PEN_UP) { |
| report_pen_up(touch); |
| touch->state = STATE_IDLE; |
| } |
| break; |
| |
| case STATE_WAIT: |
| if (event != EVENT_TIMEDOUT) |
| break; |
| |
| if (is_pen_down(touch)) { |
| start_tsi(touch); |
| touch->state = STATE_BUSY; |
| } else { |
| report_pen_up(touch); |
| touch->state = STATE_IDLE; |
| } |
| break; |
| } |
| return; |
| |
| err_reset: |
| touch->state = STATE_IDLE; |
| stop_tsi(touch); |
| detect_pen_down(touch, 1); |
| } |
| |
| static void da9034_tsi_work(struct work_struct *work) |
| { |
| struct da9034_touch *touch = |
| container_of(work, struct da9034_touch, tsi_work.work); |
| |
| da9034_event_handler(touch, EVENT_TIMEDOUT); |
| } |
| |
| static int da9034_touch_notifier(struct notifier_block *nb, |
| unsigned long event, void *data) |
| { |
| struct da9034_touch *touch = |
| container_of(nb, struct da9034_touch, notifier); |
| |
| if (event & DA9034_EVENT_TSI_READY) |
| da9034_event_handler(touch, EVENT_TSI_READY); |
| |
| if ((event & DA9034_EVENT_PEN_DOWN) && touch->state == STATE_IDLE) |
| da9034_event_handler(touch, EVENT_PEN_DOWN); |
| |
| return 0; |
| } |
| |
| static int da9034_touch_open(struct input_dev *dev) |
| { |
| struct da9034_touch *touch = input_get_drvdata(dev); |
| int ret; |
| |
| ret = da903x_register_notifier(touch->da9034_dev, &touch->notifier, |
| DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY); |
| if (ret) |
| return -EBUSY; |
| |
| /* Enable ADC LDO */ |
| ret = da903x_set_bits(touch->da9034_dev, |
| DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN); |
| if (ret) |
| return ret; |
| |
| /* TSI_DELAY: 3 slots, TSI_SKIP: 3 slots */ |
| ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL1, 0x1b); |
| if (ret) |
| return ret; |
| |
| ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL2, 0x00); |
| if (ret) |
| return ret; |
| |
| touch->state = STATE_IDLE; |
| detect_pen_down(touch, 1); |
| |
| return 0; |
| } |
| |
| static void da9034_touch_close(struct input_dev *dev) |
| { |
| struct da9034_touch *touch = input_get_drvdata(dev); |
| |
| da903x_unregister_notifier(touch->da9034_dev, &touch->notifier, |
| DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY); |
| |
| cancel_delayed_work_sync(&touch->tsi_work); |
| |
| touch->state = STATE_IDLE; |
| stop_tsi(touch); |
| detect_pen_down(touch, 0); |
| |
| /* Disable ADC LDO */ |
| da903x_clr_bits(touch->da9034_dev, |
| DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN); |
| } |
| |
| |
| static int da9034_touch_probe(struct platform_device *pdev) |
| { |
| struct da9034_touch_pdata *pdata = dev_get_platdata(&pdev->dev); |
| struct da9034_touch *touch; |
| struct input_dev *input_dev; |
| int error; |
| |
| touch = devm_kzalloc(&pdev->dev, sizeof(struct da9034_touch), |
| GFP_KERNEL); |
| if (!touch) { |
| dev_err(&pdev->dev, "failed to allocate driver data\n"); |
| return -ENOMEM; |
| } |
| |
| touch->da9034_dev = pdev->dev.parent; |
| |
| if (pdata) { |
| touch->interval_ms = pdata->interval_ms; |
| touch->x_inverted = pdata->x_inverted; |
| touch->y_inverted = pdata->y_inverted; |
| } else { |
| /* fallback into default */ |
| touch->interval_ms = 10; |
| } |
| |
| INIT_DELAYED_WORK(&touch->tsi_work, da9034_tsi_work); |
| touch->notifier.notifier_call = da9034_touch_notifier; |
| |
| input_dev = devm_input_allocate_device(&pdev->dev); |
| if (!input_dev) { |
| dev_err(&pdev->dev, "failed to allocate input device\n"); |
| return -ENOMEM; |
| } |
| |
| input_dev->name = pdev->name; |
| input_dev->open = da9034_touch_open; |
| input_dev->close = da9034_touch_close; |
| input_dev->dev.parent = &pdev->dev; |
| |
| __set_bit(EV_ABS, input_dev->evbit); |
| __set_bit(ABS_X, input_dev->absbit); |
| __set_bit(ABS_Y, input_dev->absbit); |
| input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0); |
| input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0); |
| |
| __set_bit(EV_KEY, input_dev->evbit); |
| __set_bit(BTN_TOUCH, input_dev->keybit); |
| |
| touch->input_dev = input_dev; |
| input_set_drvdata(input_dev, touch); |
| |
| error = input_register_device(input_dev); |
| if (error) |
| return error; |
| |
| return 0; |
| } |
| |
| static struct platform_driver da9034_touch_driver = { |
| .driver = { |
| .name = "da9034-touch", |
| }, |
| .probe = da9034_touch_probe, |
| }; |
| module_platform_driver(da9034_touch_driver); |
| |
| MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9034"); |
| MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>, Bin Yang <bin.yang@marvell.com>"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:da9034-touch"); |
