1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) 2000-2001 Vojtech Pavlik 4 */ 5 6 /* 7 * Gunze AHL-51S touchscreen driver for Linux 8 */ 9 10 #include <linux/errno.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/slab.h> 14 #include <linux/input.h> 15 #include <linux/serio.h> 16 17 #define DRIVER_DESC "Gunze AHL-51S touchscreen driver" 18 19 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 20 MODULE_DESCRIPTION(DRIVER_DESC); 21 MODULE_LICENSE("GPL"); 22 23 /* 24 * Definitions & global arrays. 25 */ 26 27 #define GUNZE_MAX_LENGTH 10 28 29 /* 30 * Per-touchscreen data. 31 */ 32 33 struct gunze { 34 struct input_dev *dev; 35 struct serio *serio; 36 int idx; 37 unsigned char data[GUNZE_MAX_LENGTH]; 38 char phys[32]; 39 }; 40 41 static void gunze_process_packet(struct gunze *gunze) 42 { 43 struct input_dev *dev = gunze->dev; 44 45 if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' || 46 (gunze->data[0] != 'T' && gunze->data[0] != 'R')) { 47 printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data); 48 return; 49 } 50 51 input_report_abs(dev, ABS_X, simple_strtoul(gunze->data + 1, NULL, 10)); 52 input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10)); 53 input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T'); 54 input_sync(dev); 55 } 56 57 static irqreturn_t gunze_interrupt(struct serio *serio, 58 unsigned char data, unsigned int flags) 59 { 60 struct gunze *gunze = serio_get_drvdata(serio); 61 62 if (data == '\r') { 63 gunze_process_packet(gunze); 64 gunze->idx = 0; 65 } else { 66 if (gunze->idx < GUNZE_MAX_LENGTH) 67 gunze->data[gunze->idx++] = data; 68 } 69 return IRQ_HANDLED; 70 } 71 72 /* 73 * gunze_disconnect() is the opposite of gunze_connect() 74 */ 75 76 static void gunze_disconnect(struct serio *serio) 77 { 78 struct gunze *gunze = serio_get_drvdata(serio); 79 80 input_get_device(gunze->dev); 81 input_unregister_device(gunze->dev); 82 serio_close(serio); 83 serio_set_drvdata(serio, NULL); 84 input_put_device(gunze->dev); 85 kfree(gunze); 86 } 87 88 /* 89 * gunze_connect() is the routine that is called when someone adds a 90 * new serio device that supports Gunze protocol and registers it as 91 * an input device. 92 */ 93 94 static int gunze_connect(struct serio *serio, struct serio_driver *drv) 95 { 96 struct gunze *gunze; 97 struct input_dev *input_dev; 98 int err; 99 100 gunze = kzalloc(sizeof(struct gunze), GFP_KERNEL); 101 input_dev = input_allocate_device(); 102 if (!gunze || !input_dev) { 103 err = -ENOMEM; 104 goto fail1; 105 } 106 107 gunze->serio = serio; 108 gunze->dev = input_dev; 109 snprintf(gunze->phys, sizeof(serio->phys), "%s/input0", serio->phys); 110 111 input_dev->name = "Gunze AHL-51S TouchScreen"; 112 input_dev->phys = gunze->phys; 113 input_dev->id.bustype = BUS_RS232; 114 input_dev->id.vendor = SERIO_GUNZE; 115 input_dev->id.product = 0x0051; 116 input_dev->id.version = 0x0100; 117 input_dev->dev.parent = &serio->dev; 118 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 119 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 120 input_set_abs_params(input_dev, ABS_X, 24, 1000, 0, 0); 121 input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0); 122 123 serio_set_drvdata(serio, gunze); 124 125 err = serio_open(serio, drv); 126 if (err) 127 goto fail2; 128 129 err = input_register_device(gunze->dev); 130 if (err) 131 goto fail3; 132 133 return 0; 134 135 fail3: serio_close(serio); 136 fail2: serio_set_drvdata(serio, NULL); 137 fail1: input_free_device(input_dev); 138 kfree(gunze); 139 return err; 140 } 141 142 /* 143 * The serio driver structure. 144 */ 145 146 static const struct serio_device_id gunze_serio_ids[] = { 147 { 148 .type = SERIO_RS232, 149 .proto = SERIO_GUNZE, 150 .id = SERIO_ANY, 151 .extra = SERIO_ANY, 152 }, 153 { 0 } 154 }; 155 156 MODULE_DEVICE_TABLE(serio, gunze_serio_ids); 157 158 static struct serio_driver gunze_drv = { 159 .driver = { 160 .name = "gunze", 161 }, 162 .description = DRIVER_DESC, 163 .id_table = gunze_serio_ids, 164 .interrupt = gunze_interrupt, 165 .connect = gunze_connect, 166 .disconnect = gunze_disconnect, 167 }; 168 169 module_serio_driver(gunze_drv); 170