1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * iNexio serial touchscreen driver |
4 | * |
5 | * Copyright (c) 2008 Richard Lemon |
6 | * Based on the mtouch driver (c) Vojtech Pavlik and Dan Streetman |
7 | */ |
8 | |
9 | |
10 | /* |
11 | * 2008/06/19 Richard Lemon <richard@codelemon.com> |
12 | * Copied mtouch.c and edited for iNexio protocol |
13 | */ |
14 | |
15 | #include <linux/errno.h> |
16 | #include <linux/kernel.h> |
17 | #include <linux/module.h> |
18 | #include <linux/slab.h> |
19 | #include <linux/input.h> |
20 | #include <linux/serio.h> |
21 | |
22 | #define DRIVER_DESC "iNexio serial touchscreen driver" |
23 | |
24 | MODULE_AUTHOR("Richard Lemon <richard@codelemon.com>" ); |
25 | MODULE_DESCRIPTION(DRIVER_DESC); |
26 | MODULE_LICENSE("GPL" ); |
27 | |
28 | /* |
29 | * Definitions & global arrays. |
30 | */ |
31 | |
32 | #define INEXIO_FORMAT_TOUCH_BIT 0x01 |
33 | #define INEXIO_FORMAT_LENGTH 5 |
34 | #define INEXIO_RESPONSE_BEGIN_BYTE 0x80 |
35 | |
36 | /* todo: check specs for max length of all responses */ |
37 | #define INEXIO_MAX_LENGTH 16 |
38 | |
39 | #define INEXIO_MIN_XC 0 |
40 | #define INEXIO_MAX_XC 0x3fff |
41 | #define INEXIO_MIN_YC 0 |
42 | #define INEXIO_MAX_YC 0x3fff |
43 | |
44 | #define INEXIO_GET_XC(data) (((data[1])<<7) | data[2]) |
45 | #define INEXIO_GET_YC(data) (((data[3])<<7) | data[4]) |
46 | #define INEXIO_GET_TOUCHED(data) (INEXIO_FORMAT_TOUCH_BIT & data[0]) |
47 | |
48 | /* |
49 | * Per-touchscreen data. |
50 | */ |
51 | |
52 | struct inexio { |
53 | struct input_dev *dev; |
54 | struct serio *serio; |
55 | int idx; |
56 | unsigned char data[INEXIO_MAX_LENGTH]; |
57 | char phys[32]; |
58 | }; |
59 | |
60 | static void inexio_process_data(struct inexio *pinexio) |
61 | { |
62 | struct input_dev *dev = pinexio->dev; |
63 | |
64 | if (INEXIO_FORMAT_LENGTH == ++pinexio->idx) { |
65 | input_report_abs(dev, ABS_X, INEXIO_GET_XC(pinexio->data)); |
66 | input_report_abs(dev, ABS_Y, INEXIO_GET_YC(pinexio->data)); |
67 | input_report_key(dev, BTN_TOUCH, INEXIO_GET_TOUCHED(pinexio->data)); |
68 | input_sync(dev); |
69 | |
70 | pinexio->idx = 0; |
71 | } |
72 | } |
73 | |
74 | static irqreturn_t inexio_interrupt(struct serio *serio, |
75 | unsigned char data, unsigned int flags) |
76 | { |
77 | struct inexio *pinexio = serio_get_drvdata(serio); |
78 | |
79 | pinexio->data[pinexio->idx] = data; |
80 | |
81 | if (INEXIO_RESPONSE_BEGIN_BYTE&pinexio->data[0]) |
82 | inexio_process_data(pinexio); |
83 | else |
84 | printk(KERN_DEBUG "inexio.c: unknown/unsynchronized data from device, byte %x\n" ,pinexio->data[0]); |
85 | |
86 | return IRQ_HANDLED; |
87 | } |
88 | |
89 | /* |
90 | * inexio_disconnect() is the opposite of inexio_connect() |
91 | */ |
92 | |
93 | static void inexio_disconnect(struct serio *serio) |
94 | { |
95 | struct inexio *pinexio = serio_get_drvdata(serio); |
96 | |
97 | input_get_device(dev: pinexio->dev); |
98 | input_unregister_device(pinexio->dev); |
99 | serio_close(serio); |
100 | serio_set_drvdata(serio, NULL); |
101 | input_put_device(dev: pinexio->dev); |
102 | kfree(objp: pinexio); |
103 | } |
104 | |
105 | /* |
106 | * inexio_connect() is the routine that is called when someone adds a |
107 | * new serio device that supports iNexio protocol and registers it as |
108 | * an input device. This is usually accomplished using inputattach. |
109 | */ |
110 | |
111 | static int inexio_connect(struct serio *serio, struct serio_driver *drv) |
112 | { |
113 | struct inexio *pinexio; |
114 | struct input_dev *input_dev; |
115 | int err; |
116 | |
117 | pinexio = kzalloc(size: sizeof(struct inexio), GFP_KERNEL); |
118 | input_dev = input_allocate_device(); |
119 | if (!pinexio || !input_dev) { |
120 | err = -ENOMEM; |
121 | goto fail1; |
122 | } |
123 | |
124 | pinexio->serio = serio; |
125 | pinexio->dev = input_dev; |
126 | snprintf(buf: pinexio->phys, size: sizeof(pinexio->phys), fmt: "%s/input0" , serio->phys); |
127 | |
128 | input_dev->name = "iNexio Serial TouchScreen" ; |
129 | input_dev->phys = pinexio->phys; |
130 | input_dev->id.bustype = BUS_RS232; |
131 | input_dev->id.vendor = SERIO_INEXIO; |
132 | input_dev->id.product = 0; |
133 | input_dev->id.version = 0x0001; |
134 | input_dev->dev.parent = &serio->dev; |
135 | input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
136 | input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); |
137 | input_set_abs_params(dev: pinexio->dev, ABS_X, INEXIO_MIN_XC, INEXIO_MAX_XC, fuzz: 0, flat: 0); |
138 | input_set_abs_params(dev: pinexio->dev, ABS_Y, INEXIO_MIN_YC, INEXIO_MAX_YC, fuzz: 0, flat: 0); |
139 | |
140 | serio_set_drvdata(serio, data: pinexio); |
141 | |
142 | err = serio_open(serio, drv); |
143 | if (err) |
144 | goto fail2; |
145 | |
146 | err = input_register_device(pinexio->dev); |
147 | if (err) |
148 | goto fail3; |
149 | |
150 | return 0; |
151 | |
152 | fail3: serio_close(serio); |
153 | fail2: serio_set_drvdata(serio, NULL); |
154 | fail1: input_free_device(dev: input_dev); |
155 | kfree(objp: pinexio); |
156 | return err; |
157 | } |
158 | |
159 | /* |
160 | * The serio driver structure. |
161 | */ |
162 | |
163 | static const struct serio_device_id inexio_serio_ids[] = { |
164 | { |
165 | .type = SERIO_RS232, |
166 | .proto = SERIO_INEXIO, |
167 | .id = SERIO_ANY, |
168 | .extra = SERIO_ANY, |
169 | }, |
170 | { 0 } |
171 | }; |
172 | |
173 | MODULE_DEVICE_TABLE(serio, inexio_serio_ids); |
174 | |
175 | static struct serio_driver inexio_drv = { |
176 | .driver = { |
177 | .name = "inexio" , |
178 | }, |
179 | .description = DRIVER_DESC, |
180 | .id_table = inexio_serio_ids, |
181 | .interrupt = inexio_interrupt, |
182 | .connect = inexio_connect, |
183 | .disconnect = inexio_disconnect, |
184 | }; |
185 | |
186 | module_serio_driver(inexio_drv); |
187 | |