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Diffstat (limited to '')
-rw-r--r-- | drivers/input/touchscreen/da9034-ts.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/da9034-ts.c b/drivers/input/touchscreen/da9034-ts.c new file mode 100644 index 000000000..2943f6a58 --- /dev/null +++ b/drivers/input/touchscreen/da9034-ts.c @@ -0,0 +1,365 @@ +// 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"); |