1// SPDX-License-Identifier: GPL-2.0
2/* suncore.c
3 *
4 * Common SUN serial routines.  Based entirely
5 * upon drivers/sbus/char/sunserial.c which is:
6 *
7 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
8 *
9 * Adaptation to new UART layer is:
10 *
11 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
12 */
13
14#include <linux/kernel.h>
15#include <linux/console.h>
16#include <linux/tty.h>
17#include <linux/errno.h>
18#include <linux/string.h>
19#include <linux/serial_core.h>
20#include <linux/sunserialcore.h>
21#include <linux/init.h>
22
23#include <asm/prom.h>
24
25
26static int sunserial_current_minor = 64;
27
28int sunserial_register_minors(struct uart_driver *drv, int count)
29{
30	int err = 0;
31
32	drv->minor = sunserial_current_minor;
33	drv->nr += count;
34	/* Register the driver on the first call */
35	if (drv->nr == count)
36		err = uart_register_driver(drv);
37	if (err == 0) {
38		sunserial_current_minor += count;
39		drv->tty_driver->name_base = drv->minor - 64;
40	}
41	return err;
42}
43EXPORT_SYMBOL(sunserial_register_minors);
44
45void sunserial_unregister_minors(struct uart_driver *drv, int count)
46{
47	drv->nr -= count;
48	sunserial_current_minor -= count;
49
50	if (drv->nr == 0)
51		uart_unregister_driver(drv);
52}
53EXPORT_SYMBOL(sunserial_unregister_minors);
54
55int sunserial_console_match(struct console *con, struct device_node *dp,
56			    struct uart_driver *drv, int line, bool ignore_line)
57{
58	if (!con)
59		return 0;
60
61	drv->cons = con;
62
63	if (of_console_device != dp)
64		return 0;
65
66	if (!ignore_line) {
67		int off = 0;
68
69		if (of_console_options &&
70		    *of_console_options == 'b')
71			off = 1;
72
73		if ((line & 1) != off)
74			return 0;
75	}
76
77	if (!console_set_on_cmdline) {
78		con->index = line;
79		add_preferred_console(con->name, line, NULL);
80	}
81	return 1;
82}
83EXPORT_SYMBOL(sunserial_console_match);
84
85void sunserial_console_termios(struct console *con, struct device_node *uart_dp)
86{
87	const char *mode, *s;
88	char mode_prop[] = "ttyX-mode";
89	int baud, bits, stop, cflag;
90	char parity;
91
92	if (of_node_name_eq(uart_dp, "rsc") ||
93	    of_node_name_eq(uart_dp, "rsc-console") ||
94	    of_node_name_eq(uart_dp, "rsc-control")) {
95		mode = of_get_property(uart_dp,
96				       "ssp-console-modes", NULL);
97		if (!mode)
98			mode = "115200,8,n,1,-";
99	} else if (of_node_name_eq(uart_dp, "lom-console")) {
100		mode = "9600,8,n,1,-";
101	} else {
102		struct device_node *dp;
103		char c;
104
105		c = 'a';
106		if (of_console_options)
107			c = *of_console_options;
108
109		mode_prop[3] = c;
110
111		dp = of_find_node_by_path("/options");
112		mode = of_get_property(dp, mode_prop, NULL);
113		if (!mode)
114			mode = "9600,8,n,1,-";
115		of_node_put(dp);
116	}
117
118	cflag = CREAD | HUPCL | CLOCAL;
119
120	s = mode;
121	baud = simple_strtoul(s, NULL, 0);
122	s = strchr(s, ',');
123	bits = simple_strtoul(++s, NULL, 0);
124	s = strchr(s, ',');
125	parity = *(++s);
126	s = strchr(s, ',');
127	stop = simple_strtoul(++s, NULL, 0);
128	s = strchr(s, ',');
129	/* XXX handshake is not handled here. */
130
131	switch (baud) {
132		case 150: cflag |= B150; break;
133		case 300: cflag |= B300; break;
134		case 600: cflag |= B600; break;
135		case 1200: cflag |= B1200; break;
136		case 2400: cflag |= B2400; break;
137		case 4800: cflag |= B4800; break;
138		case 9600: cflag |= B9600; break;
139		case 19200: cflag |= B19200; break;
140		case 38400: cflag |= B38400; break;
141		case 57600: cflag |= B57600; break;
142		case 115200: cflag |= B115200; break;
143		case 230400: cflag |= B230400; break;
144		case 460800: cflag |= B460800; break;
145		default: baud = 9600; cflag |= B9600; break;
146	}
147
148	switch (bits) {
149		case 5: cflag |= CS5; break;
150		case 6: cflag |= CS6; break;
151		case 7: cflag |= CS7; break;
152		case 8: cflag |= CS8; break;
153		default: cflag |= CS8; break;
154	}
155
156	switch (parity) {
157		case 'o': cflag |= (PARENB | PARODD); break;
158		case 'e': cflag |= PARENB; break;
159		case 'n': default: break;
160	}
161
162	switch (stop) {
163		case 2: cflag |= CSTOPB; break;
164		case 1: default: break;
165	}
166
167	con->cflag = cflag;
168}
169
170/* Sun serial MOUSE auto baud rate detection.  */
171static struct mouse_baud_cflag {
172	int baud;
173	unsigned int cflag;
174} mouse_baud_table[] = {
175	{ 1200, B1200 },
176	{ 2400, B2400 },
177	{ 4800, B4800 },
178	{ 9600, B9600 },
179	{ -1, ~0 },
180	{ -1, ~0 },
181};
182
183unsigned int suncore_mouse_baud_cflag_next(unsigned int cflag, int *new_baud)
184{
185	int i;
186
187	for (i = 0; mouse_baud_table[i].baud != -1; i++)
188		if (mouse_baud_table[i].cflag == (cflag & CBAUD))
189			break;
190
191	i += 1;
192	if (mouse_baud_table[i].baud == -1)
193		i = 0;
194
195	*new_baud = mouse_baud_table[i].baud;
196	return mouse_baud_table[i].cflag;
197}
198
199EXPORT_SYMBOL(suncore_mouse_baud_cflag_next);
200
201/* Basically, when the baud rate is wrong the mouse spits out
202 * breaks to us.
203 */
204int suncore_mouse_baud_detection(unsigned char ch, int is_break)
205{
206	static int mouse_got_break = 0;
207	static int ctr = 0;
208
209	if (is_break) {
210		/* Let a few normal bytes go by before we jump the gun
211		 * and say we need to try another baud rate.
212		 */
213		if (mouse_got_break && ctr < 8)
214			return 1;
215
216		/* Ok, we need to try another baud. */
217		ctr = 0;
218		mouse_got_break = 1;
219		return 2;
220	}
221	if (mouse_got_break) {
222		ctr++;
223		if (ch == 0x87) {
224			/* Correct baud rate determined. */
225			mouse_got_break = 0;
226		}
227		return 1;
228	}
229	return 0;
230}
231
232EXPORT_SYMBOL(suncore_mouse_baud_detection);
233
234static int __init suncore_init(void)
235{
236	return 0;
237}
238device_initcall(suncore_init);
239
240#if 0 /* ..def MODULE ; never supported as such */
241MODULE_AUTHOR("Eddie C. Dost, David S. Miller");
242MODULE_DESCRIPTION("Sun serial common layer");
243MODULE_LICENSE("GPL");
244#endif
245