1 /* 2 * udbg interface to hvc_console.c 3 * 4 * (C) Copyright David Gibson, IBM Corporation 2008. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 */ 20 21 #include <linux/console.h> 22 #include <linux/delay.h> 23 #include <linux/err.h> 24 #include <linux/init.h> 25 #include <linux/moduleparam.h> 26 #include <linux/types.h> 27 #include <linux/irq.h> 28 29 #include <asm/udbg.h> 30 31 #include "hvc_console.h" 32 33 struct hvc_struct *hvc_udbg_dev; 34 35 static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count) 36 { 37 int i; 38 39 for (i = 0; i < count && udbg_putc; i++) 40 udbg_putc(buf[i]); 41 42 return i; 43 } 44 45 static int hvc_udbg_get(uint32_t vtermno, char *buf, int count) 46 { 47 int i, c; 48 49 if (!udbg_getc_poll) 50 return 0; 51 52 for (i = 0; i < count; i++) { 53 if ((c = udbg_getc_poll()) == -1) 54 break; 55 buf[i] = c; 56 } 57 58 return i; 59 } 60 61 static const struct hv_ops hvc_udbg_ops = { 62 .get_chars = hvc_udbg_get, 63 .put_chars = hvc_udbg_put, 64 }; 65 66 static int __init hvc_udbg_init(void) 67 { 68 struct hvc_struct *hp; 69 70 if (!udbg_putc) 71 return -ENODEV; 72 73 BUG_ON(hvc_udbg_dev); 74 75 hp = hvc_alloc(0, 0, &hvc_udbg_ops, 16); 76 if (IS_ERR(hp)) 77 return PTR_ERR(hp); 78 79 hvc_udbg_dev = hp; 80 81 return 0; 82 } 83 module_init(hvc_udbg_init); 84 85 static void __exit hvc_udbg_exit(void) 86 { 87 if (hvc_udbg_dev) 88 hvc_remove(hvc_udbg_dev); 89 } 90 module_exit(hvc_udbg_exit); 91 92 static int __init hvc_udbg_console_init(void) 93 { 94 if (!udbg_putc) 95 return -ENODEV; 96 97 hvc_instantiate(0, 0, &hvc_udbg_ops); 98 add_preferred_console("hvc", 0, NULL); 99 100 return 0; 101 } 102 console_initcall(hvc_udbg_console_init); 103