drivers/input/serio/ct82c710.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 1999-2001 Vojtech Pavlik
   4  */
   5
   6 /*
   7  *  82C710 C&T mouse port chip driver for Linux
   8  */
   9
  10 #include <linux/delay.h>
  11 #include <linux/module.h>
  12 #include <linux/ioport.h>
  13 #include <linux/init.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/serio.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/slab.h>
  20
  21 #include <asm/io.h>
  22
  23 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  24 MODULE_DESCRIPTION("82C710 C&T mouse port chip driver");
  25 MODULE_LICENSE("GPL");
  26
  27 /*
  28  * ct82c710 interface
  29  */
  30
  31 #define CT82C710_DEV_IDLE     0x01              /* Device Idle */
  32 #define CT82C710_RX_FULL      0x02              /* Device Char received */
  33 #define CT82C710_TX_IDLE      0x04              /* Device XMIT Idle */
  34 #define CT82C710_RESET        0x08              /* Device Reset */
  35 #define CT82C710_INTS_ON      0x10              /* Device Interrupt On */
  36 #define CT82C710_ERROR_FLAG   0x20              /* Device Error */
  37 #define CT82C710_CLEAR        0x40              /* Device Clear */
  38 #define CT82C710_ENABLE       0x80              /* Device Enable */
  39
  40 #define CT82C710_IRQ          12
  41
  42 #define CT82C710_DATA         ct82c710_iores.start
  43 #define CT82C710_STATUS       (ct82c710_iores.start + 1)
  44
  45 static struct serio *ct82c710_port;
  46 static struct platform_device *ct82c710_device;
  47 static struct resource ct82c710_iores;
  48
  49 /*
  50  * Interrupt handler for the 82C710 mouse port. A character
  51  * is waiting in the 82C710.
  52  */
  53
  54 static irqreturn_t ct82c710_interrupt(int cpl, void *dev_id)
  55 {
  56         return serio_interrupt(ct82c710_port, inb(CT82C710_DATA), 0);
  57 }
  58
  59 /*
  60  * Wait for device to send output char and flush any input char.
  61  */
  62
  63 static int ct82c170_wait(void)
  64 {
  65         int timeout = 60000;
  66
  67         while ((inb(CT82C710_STATUS) & (CT82C710_RX_FULL | CT82C710_TX_IDLE | CT82C710_DEV_IDLE))
  68                        != (CT82C710_DEV_IDLE | CT82C710_TX_IDLE) && timeout) {
  69
  70                 if (inb_p(CT82C710_STATUS) & CT82C710_RX_FULL) inb_p(CT82C710_DATA);
  71
  72                 udelay(1);
  73                 timeout--;
  74         }
  75
  76         return !timeout;
  77 }
  78
  79 static void ct82c710_close(struct serio *serio)
  80 {
  81         if (ct82c170_wait())
  82                 printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
  83
  84         outb_p(inb_p(CT82C710_STATUS) & ~(CT82C710_ENABLE | CT82C710_INTS_ON), CT82C710_STATUS);
  85
  86         if (ct82c170_wait())
  87                 printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
  88
  89         free_irq(CT82C710_IRQ, NULL);
  90 }
  91
  92 static int ct82c710_open(struct serio *serio)
  93 {
  94         unsigned char status;
  95         int err;
  96
  97         err = request_irq(CT82C710_IRQ, ct82c710_interrupt, 0, "ct82c710", NULL);
  98         if (err)
  99                 return err;
 100
 101         status = inb_p(CT82C710_STATUS);
 102
 103         status |= (CT82C710_ENABLE | CT82C710_RESET);
 104         outb_p(status, CT82C710_STATUS);
 105
 106         status &= ~(CT82C710_RESET);
 107         outb_p(status, CT82C710_STATUS);
 108
 109         status |= CT82C710_INTS_ON;
 110         outb_p(status, CT82C710_STATUS);        /* Enable interrupts */
 111
 112         while (ct82c170_wait()) {
 113                 printk(KERN_ERR "ct82c710: Device busy in open()\n");
 114                 status &= ~(CT82C710_ENABLE | CT82C710_INTS_ON);
 115                 outb_p(status, CT82C710_STATUS);
 116                 free_irq(CT82C710_IRQ, NULL);
 117                 return -EBUSY;
 118         }
 119
 120         return 0;
 121 }
 122
 123 /*
 124  * Write to the 82C710 mouse device.
 125  */
 126
 127 static int ct82c710_write(struct serio *port, unsigned char c)
 128 {
 129         if (ct82c170_wait()) return -1;
 130         outb_p(c, CT82C710_DATA);
 131         return 0;
 132 }
 133
 134 /*
 135  * See if we can find a 82C710 device. Read mouse address.
 136  */
 137
 138 static int __init ct82c710_detect(void)
 139 {
 140         outb_p(0x55, 0x2fa);                            /* Any value except 9, ff or 36 */
 141         outb_p(0xaa, 0x3fa);                            /* Inverse of 55 */
 142         outb_p(0x36, 0x3fa);                            /* Address the chip */
 143         outb_p(0xe4, 0x3fa);                            /* 390/4; 390 = config address */
 144         outb_p(0x1b, 0x2fa);                            /* Inverse of e4 */
 145         outb_p(0x0f, 0x390);                            /* Write index */
 146         if (inb_p(0x391) != 0xe4)                       /* Config address found? */
 147                 return -ENODEV;                         /* No: no 82C710 here */
 148
 149         outb_p(0x0d, 0x390);                            /* Write index */
 150         ct82c710_iores.start = inb_p(0x391) << 2;       /* Get mouse I/O address */
 151         ct82c710_iores.end = ct82c710_iores.start + 1;
 152         ct82c710_iores.flags = IORESOURCE_IO;
 153         outb_p(0x0f, 0x390);
 154         outb_p(0x0f, 0x391);                            /* Close config mode */
 155
 156         return 0;
 157 }
 158
 159 static int ct82c710_probe(struct platform_device *dev)
 160 {
 161         ct82c710_port = kzalloc(sizeof(*ct82c710_port), GFP_KERNEL);
 162         if (!ct82c710_port)
 163                 return -ENOMEM;
 164
 165         ct82c710_port->id.type = SERIO_8042;
 166         ct82c710_port->dev.parent = &dev->dev;
 167         ct82c710_port->open = ct82c710_open;
 168         ct82c710_port->close = ct82c710_close;
 169         ct82c710_port->write = ct82c710_write;
 170         strscpy(ct82c710_port->name, "C&T 82c710 mouse port",
 171                 sizeof(ct82c710_port->name));
 172         snprintf(ct82c710_port->phys, sizeof(ct82c710_port->phys),
 173                  "isa%16llx/serio0", (unsigned long long)CT82C710_DATA);
 174
 175         serio_register_port(ct82c710_port);
 176
 177         printk(KERN_INFO "serio: C&T 82c710 mouse port at %#llx irq %d\n",
 178                 (unsigned long long)CT82C710_DATA, CT82C710_IRQ);
 179
 180         return 0;
 181 }
 182
 183 static void ct82c710_remove(struct platform_device *dev)
 184 {
 185         serio_unregister_port(ct82c710_port);
 186 }
 187
 188 static struct platform_driver ct82c710_driver = {
 189         .driver         = {
 190                 .name   = "ct82c710",
 191         },
 192         .probe          = ct82c710_probe,
 193         .remove         = ct82c710_remove,
 194 };
 195
 196
 197 static int __init ct82c710_init(void)
 198 {
 199         int error;
 200
 201         error = ct82c710_detect();
 202         if (error)
 203                 return error;
 204
 205         error = platform_driver_register(&ct82c710_driver);
 206         if (error)
 207                 return error;
 208
 209         ct82c710_device = platform_device_alloc("ct82c710", -1);
 210         if (!ct82c710_device) {
 211                 error = -ENOMEM;
 212                 goto err_unregister_driver;
 213         }
 214
 215         error = platform_device_add_resources(ct82c710_device, &ct82c710_iores, 1);
 216         if (error)
 217                 goto err_free_device;
 218
 219         error = platform_device_add(ct82c710_device);
 220         if (error)
 221                 goto err_free_device;
 222
 223         return 0;
 224
 225  err_free_device:
 226         platform_device_put(ct82c710_device);
 227  err_unregister_driver:
 228         platform_driver_unregister(&ct82c710_driver);
 229         return error;
 230 }
 231
 232 static void __exit ct82c710_exit(void)
 233 {
 234         platform_device_unregister(ct82c710_device);
 235         platform_driver_unregister(&ct82c710_driver);
 236 }
 237
 238 module_init(ct82c710_init);
 239 module_exit(ct82c710_exit);