xref: /openbmc/linux/drivers/tty/serial/suncore.c (revision 4f6cce39)
1 /* suncore.c
2  *
3  * Common SUN serial routines.  Based entirely
4  * upon drivers/sbus/char/sunserial.c which is:
5  *
6  * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
7  *
8  * Adaptation to new UART layer is:
9  *
10  * Copyright (C) 2002 David S. Miller (davem@redhat.com)
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/console.h>
15 #include <linux/tty.h>
16 #include <linux/errno.h>
17 #include <linux/string.h>
18 #include <linux/serial_core.h>
19 #include <linux/sunserialcore.h>
20 #include <linux/init.h>
21 
22 #include <asm/prom.h>
23 
24 
25 static int sunserial_current_minor = 64;
26 
27 int sunserial_register_minors(struct uart_driver *drv, int count)
28 {
29 	int err = 0;
30 
31 	drv->minor = sunserial_current_minor;
32 	drv->nr += count;
33 	/* Register the driver on the first call */
34 	if (drv->nr == count)
35 		err = uart_register_driver(drv);
36 	if (err == 0) {
37 		sunserial_current_minor += count;
38 		drv->tty_driver->name_base = drv->minor - 64;
39 	}
40 	return err;
41 }
42 EXPORT_SYMBOL(sunserial_register_minors);
43 
44 void sunserial_unregister_minors(struct uart_driver *drv, int count)
45 {
46 	drv->nr -= count;
47 	sunserial_current_minor -= count;
48 
49 	if (drv->nr == 0)
50 		uart_unregister_driver(drv);
51 }
52 EXPORT_SYMBOL(sunserial_unregister_minors);
53 
54 int sunserial_console_match(struct console *con, struct device_node *dp,
55 			    struct uart_driver *drv, int line, bool ignore_line)
56 {
57 	if (!con)
58 		return 0;
59 
60 	drv->cons = con;
61 
62 	if (of_console_device != dp)
63 		return 0;
64 
65 	if (!ignore_line) {
66 		int off = 0;
67 
68 		if (of_console_options &&
69 		    *of_console_options == 'b')
70 			off = 1;
71 
72 		if ((line & 1) != off)
73 			return 0;
74 	}
75 
76 	if (!console_set_on_cmdline) {
77 		con->index = line;
78 		add_preferred_console(con->name, line, NULL);
79 	}
80 	return 1;
81 }
82 EXPORT_SYMBOL(sunserial_console_match);
83 
84 void sunserial_console_termios(struct console *con, struct device_node *uart_dp)
85 {
86 	const char *mode, *s;
87 	char mode_prop[] = "ttyX-mode";
88 	int baud, bits, stop, cflag;
89 	char parity;
90 
91 	if (!strcmp(uart_dp->name, "rsc") ||
92 	    !strcmp(uart_dp->name, "rsc-console") ||
93 	    !strcmp(uart_dp->name, "rsc-control")) {
94 		mode = of_get_property(uart_dp,
95 				       "ssp-console-modes", NULL);
96 		if (!mode)
97 			mode = "115200,8,n,1,-";
98 	} else if (!strcmp(uart_dp->name, "lom-console")) {
99 		mode = "9600,8,n,1,-";
100 	} else {
101 		struct device_node *dp;
102 		char c;
103 
104 		c = 'a';
105 		if (of_console_options)
106 			c = *of_console_options;
107 
108 		mode_prop[3] = c;
109 
110 		dp = of_find_node_by_path("/options");
111 		mode = of_get_property(dp, mode_prop, NULL);
112 		if (!mode)
113 			mode = "9600,8,n,1,-";
114 	}
115 
116 	cflag = CREAD | HUPCL | CLOCAL;
117 
118 	s = mode;
119 	baud = simple_strtoul(s, NULL, 0);
120 	s = strchr(s, ',');
121 	bits = simple_strtoul(++s, NULL, 0);
122 	s = strchr(s, ',');
123 	parity = *(++s);
124 	s = strchr(s, ',');
125 	stop = simple_strtoul(++s, NULL, 0);
126 	s = strchr(s, ',');
127 	/* XXX handshake is not handled here. */
128 
129 	switch (baud) {
130 		case 150: cflag |= B150; break;
131 		case 300: cflag |= B300; break;
132 		case 600: cflag |= B600; break;
133 		case 1200: cflag |= B1200; break;
134 		case 2400: cflag |= B2400; break;
135 		case 4800: cflag |= B4800; break;
136 		case 9600: cflag |= B9600; break;
137 		case 19200: cflag |= B19200; break;
138 		case 38400: cflag |= B38400; break;
139 		case 57600: cflag |= B57600; break;
140 		case 115200: cflag |= B115200; break;
141 		case 230400: cflag |= B230400; break;
142 		case 460800: cflag |= B460800; break;
143 		default: baud = 9600; cflag |= B9600; break;
144 	}
145 
146 	switch (bits) {
147 		case 5: cflag |= CS5; break;
148 		case 6: cflag |= CS6; break;
149 		case 7: cflag |= CS7; break;
150 		case 8: cflag |= CS8; break;
151 		default: cflag |= CS8; break;
152 	}
153 
154 	switch (parity) {
155 		case 'o': cflag |= (PARENB | PARODD); break;
156 		case 'e': cflag |= PARENB; break;
157 		case 'n': default: break;
158 	}
159 
160 	switch (stop) {
161 		case 2: cflag |= CSTOPB; break;
162 		case 1: default: break;
163 	}
164 
165 	con->cflag = cflag;
166 }
167 
168 /* Sun serial MOUSE auto baud rate detection.  */
169 static struct mouse_baud_cflag {
170 	int baud;
171 	unsigned int cflag;
172 } mouse_baud_table[] = {
173 	{ 1200, B1200 },
174 	{ 2400, B2400 },
175 	{ 4800, B4800 },
176 	{ 9600, B9600 },
177 	{ -1, ~0 },
178 	{ -1, ~0 },
179 };
180 
181 unsigned int suncore_mouse_baud_cflag_next(unsigned int cflag, int *new_baud)
182 {
183 	int i;
184 
185 	for (i = 0; mouse_baud_table[i].baud != -1; i++)
186 		if (mouse_baud_table[i].cflag == (cflag & CBAUD))
187 			break;
188 
189 	i += 1;
190 	if (mouse_baud_table[i].baud == -1)
191 		i = 0;
192 
193 	*new_baud = mouse_baud_table[i].baud;
194 	return mouse_baud_table[i].cflag;
195 }
196 
197 EXPORT_SYMBOL(suncore_mouse_baud_cflag_next);
198 
199 /* Basically, when the baud rate is wrong the mouse spits out
200  * breaks to us.
201  */
202 int suncore_mouse_baud_detection(unsigned char ch, int is_break)
203 {
204 	static int mouse_got_break = 0;
205 	static int ctr = 0;
206 
207 	if (is_break) {
208 		/* Let a few normal bytes go by before we jump the gun
209 		 * and say we need to try another baud rate.
210 		 */
211 		if (mouse_got_break && ctr < 8)
212 			return 1;
213 
214 		/* Ok, we need to try another baud. */
215 		ctr = 0;
216 		mouse_got_break = 1;
217 		return 2;
218 	}
219 	if (mouse_got_break) {
220 		ctr++;
221 		if (ch == 0x87) {
222 			/* Correct baud rate determined. */
223 			mouse_got_break = 0;
224 		}
225 		return 1;
226 	}
227 	return 0;
228 }
229 
230 EXPORT_SYMBOL(suncore_mouse_baud_detection);
231 
232 static int __init suncore_init(void)
233 {
234 	return 0;
235 }
236 device_initcall(suncore_init);
237 
238 #if 0 /* ..def MODULE ; never supported as such */
239 MODULE_AUTHOR("Eddie C. Dost, David S. Miller");
240 MODULE_DESCRIPTION("Sun serial common layer");
241 MODULE_LICENSE("GPL");
242 #endif
243