Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * IBM RTAS driver interface to hvc_console.c
  3  *
  4  * (C) Copyright IBM Corporation 2001-2005
  5  * (C) Copyright Red Hat, Inc. 2005
  6  *
  7  * Author(s): Maximino Augilar <IBM STI Design Center>
  8  *          : Ryan S. Arnold <rsa@us.ibm.com>
  9  *          : Utz Bacher <utz.bacher@de.ibm.com>
 10  *          : David Woodhouse <dwmw2@infradead.org>
 11  *
 12  *    inspired by drivers/char/hvc_console.c
 13  *    written by Anton Blanchard and Paul Mackerras
 14  *
 15  * This program is free software; you can redistribute it and/or modify
 16  * it under the terms of the GNU General Public License as published by
 17  * the Free Software Foundation; either version 2 of the License, or
 18  * (at your option) any later version.
 19  *
 20  * This program is distributed in the hope that it will be useful,
 21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 23  * GNU General Public License for more details.
 24  *
 25  * You should have received a copy of the GNU General Public License
 26  * along with this program; if not, write to the Free Software
 27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 28  */
 29 
 30 #include <linux/console.h>
 31 #include <linux/delay.h>
 32 #include <linux/err.h>
 33 #include <linux/init.h>
 34 #include <linux/moduleparam.h>
 35 #include <linux/types.h>
 36 
 37 #include <asm/irq.h>
 38 #include <asm/rtas.h>
 39 #include "hvc_console.h"
 40 
 41 #define hvc_rtas_cookie 0x67781e15
 42 struct hvc_struct *hvc_rtas_dev;
 43 
 44 static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
 45 static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
 46 
 47 static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
 48                 int count)
 49 {
 50         int i;
 51 
 52         for (i = 0; i < count; i++) {
 53                 if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
 54                         break;
 55         }
 56 
 57         return i;
 58 }
 59 
 60 static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
 61 {
 62         int i, c;
 63 
 64         for (i = 0; i < count; i++) {
 65                 if (rtas_call(rtascons_get_char_token, 0, 2, &c))
 66                         break;
 67 
 68                 buf[i] = c;
 69         }
 70 
 71         return i;
 72 }
 73 
 74 static struct hv_ops hvc_rtas_get_put_ops = {
 75         .get_chars = hvc_rtas_read_console,
 76         .put_chars = hvc_rtas_write_console,
 77 };
 78 
 79 static int __init hvc_rtas_init(void)
 80 {
 81         struct hvc_struct *hp;
 82 
 83         if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
 84                 rtascons_put_char_token = rtas_token("put-term-char");
 85         if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
 86                 return -EIO;
 87 
 88         if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
 89                 rtascons_get_char_token = rtas_token("get-term-char");
 90         if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
 91                 return -EIO;
 92 
 93         BUG_ON(hvc_rtas_dev);
 94 
 95         /* Allocate an hvc_struct for the console device we instantiated
 96          * earlier.  Save off hp so that we can return it on exit */
 97         hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops, 16);
 98         if (IS_ERR(hp))
 99                 return PTR_ERR(hp);
100 
101         hvc_rtas_dev = hp;
102 
103         return 0;
104 }
105 module_init(hvc_rtas_init);
106 
107 /* This will tear down the tty portion of the driver */
108 static void __exit hvc_rtas_exit(void)
109 {
110         /* Really the fun isn't over until the worker thread breaks down and
111          * the tty cleans up */
112         if (hvc_rtas_dev)
113                 hvc_remove(hvc_rtas_dev);
114 }
115 module_exit(hvc_rtas_exit);
116 
117 /* This will happen prior to module init.  There is no tty at this time? */
118 static int __init hvc_rtas_console_init(void)
119 {
120         rtascons_put_char_token = rtas_token("put-term-char");
121         if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
122                 return -EIO;
123 
124         rtascons_get_char_token = rtas_token("get-term-char");
125         if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
126                 return -EIO;
127 
128         hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
129         add_preferred_console("hvc", 0, NULL);
130 
131         return 0;
132 }
133 console_initcall(hvc_rtas_console_init);
134 
  This page was automatically generated by the LXR engine.