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 /* 11 */ 12 13 #include <linux/errno.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/slab.h> 17 #include <linux/input.h> 18 #include <linux/serio.h> 19 20 #define DRIVER_DESC "Gunze AHL-51S touchscreen driver" 21 22 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 23 MODULE_DESCRIPTION(DRIVER_DESC); 24 MODULE_LICENSE("GPL"); 25 26 /* 27 * Definitions & global arrays. 28 */ 29 30 #define GUNZE_MAX_LENGTH 10 31 32 /* 33 * Per-touchscreen data. 34 */ 35 36 struct gunze { 37 struct input_dev *dev; 38 struct serio *serio; 39 int idx; 40 unsigned char data[GUNZE_MAX_LENGTH]; 41 char phys[32]; 42 }; 43 44 static void gunze_process_packet(struct gunze *gunze) 45 { 46 struct input_dev *dev = gunze->dev; 47 48 if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' || 49 (gunze->data[0] != 'T' && gunze->data[0] != 'R')) { 50 printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data); 51 return; 52 } 53 54 input_report_abs(dev, ABS_X, simple_strtoul(gunze->data + 1, NULL, 10)); 55 input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10)); 56 input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T'); 57 input_sync(dev); 58 } 59 60 static irqreturn_t gunze_interrupt(struct serio *serio, 61 unsigned char data, unsigned int flags) 62 { 63 struct gunze *gunze = serio_get_drvdata(serio); 64 65 if (data == '\r') { 66 gunze_process_packet(gunze); 67 gunze->idx = 0; 68 } else { 69 if (gunze->idx < GUNZE_MAX_LENGTH) 70 gunze->data[gunze->idx++] = data; 71 } 72 return IRQ_HANDLED; 73 } 74 75 /* 76 * gunze_disconnect() is the opposite of gunze_connect() 77 */ 78 79 static void gunze_disconnect(struct serio *serio) 80 { 81 struct gunze *gunze = serio_get_drvdata(serio); 82 83 input_get_device(gunze->dev); 84 input_unregister_device(gunze->dev); 85 serio_close(serio); 86 serio_set_drvdata(serio, NULL); 87 input_put_device(gunze->dev); 88 kfree(gunze); 89 } 90 91 /* 92 * gunze_connect() is the routine that is called when someone adds a 93 * new serio device that supports Gunze protocol and registers it as 94 * an input device. 95 */ 96 97 static int gunze_connect(struct serio *serio, struct serio_driver *drv) 98 { 99 struct gunze *gunze; 100 struct input_dev *input_dev; 101 int err; 102 103 gunze = kzalloc(sizeof(struct gunze), GFP_KERNEL); 104 input_dev = input_allocate_device(); 105 if (!gunze || !input_dev) { 106 err = -ENOMEM; 107 goto fail1; 108 } 109 110 gunze->serio = serio; 111 gunze->dev = input_dev; 112 snprintf(gunze->phys, sizeof(serio->phys), "%s/input0", serio->phys); 113 114 input_dev->name = "Gunze AHL-51S TouchScreen"; 115 input_dev->phys = gunze->phys; 116 input_dev->id.bustype = BUS_RS232; 117 input_dev->id.vendor = SERIO_GUNZE; 118 input_dev->id.product = 0x0051; 119 input_dev->id.version = 0x0100; 120 input_dev->dev.parent = &serio->dev; 121 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 122 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 123 input_set_abs_params(input_dev, ABS_X, 24, 1000, 0, 0); 124 input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0); 125 126 serio_set_drvdata(serio, gunze); 127 128 err = serio_open(serio, drv); 129 if (err) 130 goto fail2; 131 132 err = input_register_device(gunze->dev); 133 if (err) 134 goto fail3; 135 136 return 0; 137 138 fail3: serio_close(serio); 139 fail2: serio_set_drvdata(serio, NULL); 140 fail1: input_free_device(input_dev); 141 kfree(gunze); 142 return err; 143 } 144 145 /* 146 * The serio driver structure. 147 */ 148 149 static const struct serio_device_id gunze_serio_ids[] = { 150 { 151 .type = SERIO_RS232, 152 .proto = SERIO_GUNZE, 153 .id = SERIO_ANY, 154 .extra = SERIO_ANY, 155 }, 156 { 0 } 157 }; 158 159 MODULE_DEVICE_TABLE(serio, gunze_serio_ids); 160 161 static struct serio_driver gunze_drv = { 162 .driver = { 163 .name = "gunze", 164 }, 165 .description = DRIVER_DESC, 166 .id_table = gunze_serio_ids, 167 .interrupt = gunze_interrupt, 168 .connect = gunze_connect, 169 .disconnect = gunze_disconnect, 170 }; 171 172 module_serio_driver(gunze_drv); 173