diff options
Diffstat (limited to 'drivers/input/touchscreen/hampshire.c')
| -rw-r--r-- | drivers/input/touchscreen/hampshire.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/hampshire.c b/drivers/input/touchscreen/hampshire.c new file mode 100644 index 0000000000..5c4d877564 --- /dev/null +++ b/drivers/input/touchscreen/hampshire.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Hampshire serial touchscreen driver + * + * Copyright (c) 2010 Adam Bennett + * Based on the dynapro driver (c) Tias Guns + */ + + +/* + * 2010/04/08 Adam Bennett <abennett72@gmail.com> + * Copied dynapro.c and edited for Hampshire 4-byte protocol + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/input.h> +#include <linux/serio.h> + +#define DRIVER_DESC "Hampshire serial touchscreen driver" + +MODULE_AUTHOR("Adam Bennett <abennett72@gmail.com>"); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define HAMPSHIRE_FORMAT_TOUCH_BIT 0x40 +#define HAMPSHIRE_FORMAT_LENGTH 4 +#define HAMPSHIRE_RESPONSE_BEGIN_BYTE 0x80 + +#define HAMPSHIRE_MIN_XC 0 +#define HAMPSHIRE_MAX_XC 0x1000 +#define HAMPSHIRE_MIN_YC 0 +#define HAMPSHIRE_MAX_YC 0x1000 + +#define HAMPSHIRE_GET_XC(data) (((data[3] & 0x0c) >> 2) | (data[1] << 2) | ((data[0] & 0x38) << 6)) +#define HAMPSHIRE_GET_YC(data) ((data[3] & 0x03) | (data[2] << 2) | ((data[0] & 0x07) << 9)) +#define HAMPSHIRE_GET_TOUCHED(data) (HAMPSHIRE_FORMAT_TOUCH_BIT & data[0]) + +/* + * Per-touchscreen data. + */ + +struct hampshire { + struct input_dev *dev; + struct serio *serio; + int idx; + unsigned char data[HAMPSHIRE_FORMAT_LENGTH]; + char phys[32]; +}; + +static void hampshire_process_data(struct hampshire *phampshire) +{ + struct input_dev *dev = phampshire->dev; + + if (HAMPSHIRE_FORMAT_LENGTH == ++phampshire->idx) { + input_report_abs(dev, ABS_X, HAMPSHIRE_GET_XC(phampshire->data)); + input_report_abs(dev, ABS_Y, HAMPSHIRE_GET_YC(phampshire->data)); + input_report_key(dev, BTN_TOUCH, + HAMPSHIRE_GET_TOUCHED(phampshire->data)); + input_sync(dev); + + phampshire->idx = 0; + } +} + +static irqreturn_t hampshire_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct hampshire *phampshire = serio_get_drvdata(serio); + + phampshire->data[phampshire->idx] = data; + + if (HAMPSHIRE_RESPONSE_BEGIN_BYTE & phampshire->data[0]) + hampshire_process_data(phampshire); + else + dev_dbg(&serio->dev, "unknown/unsynchronized data: %x\n", + phampshire->data[0]); + + return IRQ_HANDLED; +} + +static void hampshire_disconnect(struct serio *serio) +{ + struct hampshire *phampshire = serio_get_drvdata(serio); + + input_get_device(phampshire->dev); + input_unregister_device(phampshire->dev); + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_put_device(phampshire->dev); + kfree(phampshire); +} + +/* + * hampshire_connect() is the routine that is called when someone adds a + * new serio device that supports hampshire protocol and registers it as + * an input device. This is usually accomplished using inputattach. + */ + +static int hampshire_connect(struct serio *serio, struct serio_driver *drv) +{ + struct hampshire *phampshire; + struct input_dev *input_dev; + int err; + + phampshire = kzalloc(sizeof(struct hampshire), GFP_KERNEL); + input_dev = input_allocate_device(); + if (!phampshire || !input_dev) { + err = -ENOMEM; + goto fail1; + } + + phampshire->serio = serio; + phampshire->dev = input_dev; + snprintf(phampshire->phys, sizeof(phampshire->phys), + "%s/input0", serio->phys); + + input_dev->name = "Hampshire Serial TouchScreen"; + input_dev->phys = phampshire->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_HAMPSHIRE; + input_dev->id.product = 0; + input_dev->id.version = 0x0001; + input_dev->dev.parent = &serio->dev; + 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(phampshire->dev, ABS_X, + HAMPSHIRE_MIN_XC, HAMPSHIRE_MAX_XC, 0, 0); + input_set_abs_params(phampshire->dev, ABS_Y, + HAMPSHIRE_MIN_YC, HAMPSHIRE_MAX_YC, 0, 0); + + serio_set_drvdata(serio, phampshire); + + err = serio_open(serio, drv); + if (err) + goto fail2; + + err = input_register_device(phampshire->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(phampshire); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id hampshire_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_HAMPSHIRE, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, hampshire_serio_ids); + +static struct serio_driver hampshire_drv = { + .driver = { + .name = "hampshire", + }, + .description = DRIVER_DESC, + .id_table = hampshire_serio_ids, + .interrupt = hampshire_interrupt, + .connect = hampshire_connect, + .disconnect = hampshire_disconnect, +}; + +module_serio_driver(hampshire_drv); |