input/serio/ct82c710.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  *  Copyright (c) 1999-2001 Vojtech Pavlik
0004  */
0005
0006 /*
0007  *  82C710 C&T mouse port chip driver for Linux
0008  */
0009
0010 /*
0011  */
0012
0013 #include <linux/delay.h>
0014 #include <linux/module.h>
0015 #include <linux/ioport.h>
0016 #include <linux/init.h>
0017 #include <linux/interrupt.h>
0018 #include <linux/serio.h>
0019 #include <linux/errno.h>
0020 #include <linux/err.h>
0021 #include <linux/platform_device.h>
0022 #include <linux/slab.h>
0023
0024 #include <asm/io.h>
0025
0026 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
0027 MODULE_DESCRIPTION("82C710 C&T mouse port chip driver");
0028 MODULE_LICENSE("GPL");
0029
0030 /*
0031  * ct82c710 interface
0032  */
0033
0034 #define CT82C710_DEV_IDLE     0x01      /* Device Idle */
0035 #define CT82C710_RX_FULL      0x02      /* Device Char received */
0036 #define CT82C710_TX_IDLE      0x04      /* Device XMIT Idle */
0037 #define CT82C710_RESET        0x08      /* Device Reset */
0038 #define CT82C710_INTS_ON      0x10      /* Device Interrupt On */
0039 #define CT82C710_ERROR_FLAG   0x20      /* Device Error */
0040 #define CT82C710_CLEAR        0x40      /* Device Clear */
0041 #define CT82C710_ENABLE       0x80      /* Device Enable */
0042
0043 #define CT82C710_IRQ          12
0044
0045 #define CT82C710_DATA         ct82c710_iores.start
0046 #define CT82C710_STATUS       (ct82c710_iores.start + 1)
0047
0048 static struct serio *ct82c710_port;
0049 static struct platform_device *ct82c710_device;
0050 static struct resource ct82c710_iores;
0051
0052 /*
0053  * Interrupt handler for the 82C710 mouse port. A character
0054  * is waiting in the 82C710.
0055  */
0056
0057 static irqreturn_t ct82c710_interrupt(int cpl, void *dev_id)
0058 {
0059     return serio_interrupt(ct82c710_port, inb(CT82C710_DATA), 0);
0060 }
0061
0062 /*
0063  * Wait for device to send output char and flush any input char.
0064  */
0065
0066 static int ct82c170_wait(void)
0067 {
0068     int timeout = 60000;
0069
0070     while ((inb(CT82C710_STATUS) & (CT82C710_RX_FULL | CT82C710_TX_IDLE | CT82C710_DEV_IDLE))
0071                != (CT82C710_DEV_IDLE | CT82C710_TX_IDLE) && timeout) {
0072
0073         if (inb_p(CT82C710_STATUS) & CT82C710_RX_FULL) inb_p(CT82C710_DATA);
0074
0075         udelay(1);
0076         timeout--;
0077     }
0078
0079     return !timeout;
0080 }
0081
0082 static void ct82c710_close(struct serio *serio)
0083 {
0084     if (ct82c170_wait())
0085         printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
0086
0087     outb_p(inb_p(CT82C710_STATUS) & ~(CT82C710_ENABLE | CT82C710_INTS_ON), CT82C710_STATUS);
0088
0089     if (ct82c170_wait())
0090         printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
0091
0092     free_irq(CT82C710_IRQ, NULL);
0093 }
0094
0095 static int ct82c710_open(struct serio *serio)
0096 {
0097     unsigned char status;
0098     int err;
0099
0100     err = request_irq(CT82C710_IRQ, ct82c710_interrupt, 0, "ct82c710", NULL);
0101     if (err)
0102         return err;
0103
0104     status = inb_p(CT82C710_STATUS);
0105
0106     status |= (CT82C710_ENABLE | CT82C710_RESET);
0107     outb_p(status, CT82C710_STATUS);
0108
0109     status &= ~(CT82C710_RESET);
0110     outb_p(status, CT82C710_STATUS);
0111
0112     status |= CT82C710_INTS_ON;
0113     outb_p(status, CT82C710_STATUS);    /* Enable interrupts */
0114
0115     while (ct82c170_wait()) {
0116         printk(KERN_ERR "ct82c710: Device busy in open()\n");
0117         status &= ~(CT82C710_ENABLE | CT82C710_INTS_ON);
0118         outb_p(status, CT82C710_STATUS);
0119         free_irq(CT82C710_IRQ, NULL);
0120         return -EBUSY;
0121     }
0122
0123     return 0;
0124 }
0125
0126 /*
0127  * Write to the 82C710 mouse device.
0128  */
0129
0130 static int ct82c710_write(struct serio *port, unsigned char c)
0131 {
0132     if (ct82c170_wait()) return -1;
0133     outb_p(c, CT82C710_DATA);
0134     return 0;
0135 }
0136
0137 /*
0138  * See if we can find a 82C710 device. Read mouse address.
0139  */
0140
0141 static int __init ct82c710_detect(void)
0142 {
0143     outb_p(0x55, 0x2fa);                /* Any value except 9, ff or 36 */
0144     outb_p(0xaa, 0x3fa);                /* Inverse of 55 */
0145     outb_p(0x36, 0x3fa);                /* Address the chip */
0146     outb_p(0xe4, 0x3fa);                /* 390/4; 390 = config address */
0147     outb_p(0x1b, 0x2fa);                /* Inverse of e4 */
0148     outb_p(0x0f, 0x390);                /* Write index */
0149     if (inb_p(0x391) != 0xe4)           /* Config address found? */
0150         return -ENODEV;             /* No: no 82C710 here */
0151
0152     outb_p(0x0d, 0x390);                /* Write index */
0153     ct82c710_iores.start = inb_p(0x391) << 2;   /* Get mouse I/O address */
0154     ct82c710_iores.end = ct82c710_iores.start + 1;
0155     ct82c710_iores.flags = IORESOURCE_IO;
0156     outb_p(0x0f, 0x390);
0157     outb_p(0x0f, 0x391);                /* Close config mode */
0158
0159     return 0;
0160 }
0161
0162 static int ct82c710_probe(struct platform_device *dev)
0163 {
0164     ct82c710_port = kzalloc(sizeof(struct serio), GFP_KERNEL);
0165     if (!ct82c710_port)
0166         return -ENOMEM;
0167
0168     ct82c710_port->id.type = SERIO_8042;
0169     ct82c710_port->dev.parent = &dev->dev;
0170     ct82c710_port->open = ct82c710_open;
0171     ct82c710_port->close = ct82c710_close;
0172     ct82c710_port->write = ct82c710_write;
0173     strlcpy(ct82c710_port->name, "C&T 82c710 mouse port",
0174         sizeof(ct82c710_port->name));
0175     snprintf(ct82c710_port->phys, sizeof(ct82c710_port->phys),
0176          "isa%16llx/serio0", (unsigned long long)CT82C710_DATA);
0177
0178     serio_register_port(ct82c710_port);
0179
0180     printk(KERN_INFO "serio: C&T 82c710 mouse port at %#llx irq %d\n",
0181         (unsigned long long)CT82C710_DATA, CT82C710_IRQ);
0182
0183     return 0;
0184 }
0185
0186 static int ct82c710_remove(struct platform_device *dev)
0187 {
0188     serio_unregister_port(ct82c710_port);
0189
0190     return 0;
0191 }
0192
0193 static struct platform_driver ct82c710_driver = {
0194     .driver     = {
0195         .name   = "ct82c710",
0196     },
0197     .probe      = ct82c710_probe,
0198     .remove     = ct82c710_remove,
0199 };
0200
0201
0202 static int __init ct82c710_init(void)
0203 {
0204     int error;
0205
0206     error = ct82c710_detect();
0207     if (error)
0208         return error;
0209
0210     error = platform_driver_register(&ct82c710_driver);
0211     if (error)
0212         return error;
0213
0214     ct82c710_device = platform_device_alloc("ct82c710", -1);
0215     if (!ct82c710_device) {
0216         error = -ENOMEM;
0217         goto err_unregister_driver;
0218     }
0219
0220     error = platform_device_add_resources(ct82c710_device, &ct82c710_iores, 1);
0221     if (error)
0222         goto err_free_device;
0223
0224     error = platform_device_add(ct82c710_device);
0225     if (error)
0226         goto err_free_device;
0227
0228     return 0;
0229
0230  err_free_device:
0231     platform_device_put(ct82c710_device);
0232  err_unregister_driver:
0233     platform_driver_unregister(&ct82c710_driver);
0234     return error;
0235 }
0236
0237 static void __exit ct82c710_exit(void)
0238 {
0239     platform_device_unregister(ct82c710_device);
0240     platform_driver_unregister(&ct82c710_driver);
0241 }
0242
0243 module_init(ct82c710_init);
0244 module_exit(ct82c710_exit);