1 /* 2 * vio driver interface to hvc_console.c 3 * 4 * This code was moved here to allow the remaing code to be reused as a 5 * generic polling mode with semi-reliable transport driver core to the 6 * console and tty subsystems. 7 * 8 * 9 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM 10 * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM 11 * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp. 12 * Copyright (C) 2004 IBM Corporation 13 * 14 * Additional Author(s): 15 * Ryan S. Arnold <rsa@us.ibm.com> 16 * 17 * This program is free software; you can redistribute it and/or modify 18 * it under the terms of the GNU General Public License as published by 19 * the Free Software Foundation; either version 2 of the License, or 20 * (at your option) any later version. 21 * 22 * This program is distributed in the hope that it will be useful, 23 * but WITHOUT ANY WARRANTY; without even the implied warranty of 24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 25 * GNU General Public License for more details. 26 * 27 * You should have received a copy of the GNU General Public License 28 * along with this program; if not, write to the Free Software 29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 30 */ 31 32 #include <linux/types.h> 33 #include <linux/init.h> 34 35 #include <asm/hvconsole.h> 36 #include <asm/vio.h> 37 #include <asm/prom.h> 38 #include <asm/firmware.h> 39 40 #include "hvc_console.h" 41 42 static const char hvc_driver_name[] = "hvc_console"; 43 44 static struct vio_device_id hvc_driver_table[] __devinitdata = { 45 {"serial", "hvterm1"}, 46 { "", "" } 47 }; 48 MODULE_DEVICE_TABLE(vio, hvc_driver_table); 49 50 static int filtered_get_chars(uint32_t vtermno, char *buf, int count) 51 { 52 unsigned long got; 53 int i; 54 55 /* 56 * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion 57 * so we play safe and avoid the situation where got > count which could 58 * overload the flip buffer. 59 */ 60 if (count < SIZE_VIO_GET_CHARS) 61 return -EAGAIN; 62 63 got = hvc_get_chars(vtermno, buf, count); 64 65 /* 66 * Work around a HV bug where it gives us a null 67 * after every \r. -- paulus 68 */ 69 for (i = 1; i < got; ++i) { 70 if (buf[i] == 0 && buf[i-1] == '\r') { 71 --got; 72 if (i < got) 73 memmove(&buf[i], &buf[i+1], 74 got - i); 75 } 76 } 77 return got; 78 } 79 80 static const struct hv_ops hvc_get_put_ops = { 81 .get_chars = filtered_get_chars, 82 .put_chars = hvc_put_chars, 83 .notifier_add = notifier_add_irq, 84 .notifier_del = notifier_del_irq, 85 .notifier_hangup = notifier_hangup_irq, 86 }; 87 88 static int __devinit hvc_vio_probe(struct vio_dev *vdev, 89 const struct vio_device_id *id) 90 { 91 struct hvc_struct *hp; 92 93 /* probed with invalid parameters. */ 94 if (!vdev || !id) 95 return -EPERM; 96 97 hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops, 98 MAX_VIO_PUT_CHARS); 99 if (IS_ERR(hp)) 100 return PTR_ERR(hp); 101 dev_set_drvdata(&vdev->dev, hp); 102 103 return 0; 104 } 105 106 static int __devexit hvc_vio_remove(struct vio_dev *vdev) 107 { 108 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev); 109 110 return hvc_remove(hp); 111 } 112 113 static struct vio_driver hvc_vio_driver = { 114 .id_table = hvc_driver_table, 115 .probe = hvc_vio_probe, 116 .remove = __devexit_p(hvc_vio_remove), 117 .driver = { 118 .name = hvc_driver_name, 119 .owner = THIS_MODULE, 120 } 121 }; 122 123 static int __init hvc_vio_init(void) 124 { 125 int rc; 126 127 if (firmware_has_feature(FW_FEATURE_ISERIES)) 128 return -EIO; 129 130 /* Register as a vio device to receive callbacks */ 131 rc = vio_register_driver(&hvc_vio_driver); 132 133 return rc; 134 } 135 module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */ 136 137 static void __exit hvc_vio_exit(void) 138 { 139 vio_unregister_driver(&hvc_vio_driver); 140 } 141 module_exit(hvc_vio_exit); 142 143 /* the device tree order defines our numbering */ 144 static int hvc_find_vtys(void) 145 { 146 struct device_node *vty; 147 int num_found = 0; 148 149 for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL; 150 vty = of_find_node_by_name(vty, "vty")) { 151 const uint32_t *vtermno; 152 153 /* We have statically defined space for only a certain number 154 * of console adapters. 155 */ 156 if (num_found >= MAX_NR_HVC_CONSOLES) { 157 of_node_put(vty); 158 break; 159 } 160 161 vtermno = of_get_property(vty, "reg", NULL); 162 if (!vtermno) 163 continue; 164 165 if (of_device_is_compatible(vty, "hvterm1")) { 166 hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops); 167 ++num_found; 168 } 169 } 170 171 return num_found; 172 } 173 console_initcall(hvc_find_vtys); 174