1 /* 2 * /dev/lcd driver for Apple Network Servers. 3 */ 4 5 #include <linux/types.h> 6 #include <linux/errno.h> 7 #include <linux/kernel.h> 8 #include <linux/miscdevice.h> 9 #include <linux/fcntl.h> 10 #include <linux/init.h> 11 #include <linux/delay.h> 12 #include <linux/fs.h> 13 14 #include <asm/uaccess.h> 15 #include <asm/sections.h> 16 #include <asm/prom.h> 17 #include <asm/io.h> 18 19 #include "ans-lcd.h" 20 21 #define ANSLCD_ADDR 0xf301c000 22 #define ANSLCD_CTRL_IX 0x00 23 #define ANSLCD_DATA_IX 0x10 24 25 static unsigned long anslcd_short_delay = 80; 26 static unsigned long anslcd_long_delay = 3280; 27 static volatile unsigned char __iomem *anslcd_ptr; 28 static DEFINE_MUTEX(anslcd_mutex); 29 30 #undef DEBUG 31 32 static void 33 anslcd_write_byte_ctrl ( unsigned char c ) 34 { 35 #ifdef DEBUG 36 printk(KERN_DEBUG "LCD: CTRL byte: %02x\n",c); 37 #endif 38 out_8(anslcd_ptr + ANSLCD_CTRL_IX, c); 39 switch(c) { 40 case 1: 41 case 2: 42 case 3: 43 udelay(anslcd_long_delay); break; 44 default: udelay(anslcd_short_delay); 45 } 46 } 47 48 static void 49 anslcd_write_byte_data ( unsigned char c ) 50 { 51 out_8(anslcd_ptr + ANSLCD_DATA_IX, c); 52 udelay(anslcd_short_delay); 53 } 54 55 static ssize_t 56 anslcd_write( struct file * file, const char __user * buf, 57 size_t count, loff_t *ppos ) 58 { 59 const char __user *p = buf; 60 int i; 61 62 #ifdef DEBUG 63 printk(KERN_DEBUG "LCD: write\n"); 64 #endif 65 66 if (!access_ok(VERIFY_READ, buf, count)) 67 return -EFAULT; 68 69 mutex_lock(&anslcd_mutex); 70 for ( i = *ppos; count > 0; ++i, ++p, --count ) 71 { 72 char c; 73 __get_user(c, p); 74 anslcd_write_byte_data( c ); 75 } 76 mutex_unlock(&anslcd_mutex); 77 *ppos = i; 78 return p - buf; 79 } 80 81 static long 82 anslcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 83 { 84 char ch, __user *temp; 85 long ret = 0; 86 87 #ifdef DEBUG 88 printk(KERN_DEBUG "LCD: ioctl(%d,%d)\n",cmd,arg); 89 #endif 90 91 mutex_lock(&anslcd_mutex); 92 93 switch ( cmd ) 94 { 95 case ANSLCD_CLEAR: 96 anslcd_write_byte_ctrl ( 0x38 ); 97 anslcd_write_byte_ctrl ( 0x0f ); 98 anslcd_write_byte_ctrl ( 0x06 ); 99 anslcd_write_byte_ctrl ( 0x01 ); 100 anslcd_write_byte_ctrl ( 0x02 ); 101 break; 102 case ANSLCD_SENDCTRL: 103 temp = (char __user *) arg; 104 __get_user(ch, temp); 105 for (; ch; temp++) { /* FIXME: This is ugly, but should work, as a \0 byte is not a valid command code */ 106 anslcd_write_byte_ctrl ( ch ); 107 __get_user(ch, temp); 108 } 109 break; 110 case ANSLCD_SETSHORTDELAY: 111 if (!capable(CAP_SYS_ADMIN)) 112 ret =-EACCES; 113 else 114 anslcd_short_delay=arg; 115 break; 116 case ANSLCD_SETLONGDELAY: 117 if (!capable(CAP_SYS_ADMIN)) 118 ret = -EACCES; 119 else 120 anslcd_long_delay=arg; 121 break; 122 default: 123 ret = -EINVAL; 124 } 125 126 mutex_unlock(&anslcd_mutex); 127 return ret; 128 } 129 130 static int 131 anslcd_open( struct inode * inode, struct file * file ) 132 { 133 return 0; 134 } 135 136 const struct file_operations anslcd_fops = { 137 .write = anslcd_write, 138 .unlocked_ioctl = anslcd_ioctl, 139 .open = anslcd_open, 140 }; 141 142 static struct miscdevice anslcd_dev = { 143 ANSLCD_MINOR, 144 "anslcd", 145 &anslcd_fops 146 }; 147 148 const char anslcd_logo[] = "********************" /* Line #1 */ 149 "* LINUX! *" /* Line #3 */ 150 "* Welcome to *" /* Line #2 */ 151 "********************"; /* Line #4 */ 152 153 static int __init 154 anslcd_init(void) 155 { 156 int a; 157 int retval; 158 struct device_node* node; 159 160 node = of_find_node_by_name(NULL, "lcd"); 161 if (!node || !node->parent || strcmp(node->parent->name, "gc")) { 162 of_node_put(node); 163 return -ENODEV; 164 } 165 of_node_put(node); 166 167 anslcd_ptr = ioremap(ANSLCD_ADDR, 0x20); 168 169 retval = misc_register(&anslcd_dev); 170 if(retval < 0){ 171 printk(KERN_INFO "LCD: misc_register failed\n"); 172 iounmap(anslcd_ptr); 173 return retval; 174 } 175 176 #ifdef DEBUG 177 printk(KERN_DEBUG "LCD: init\n"); 178 #endif 179 180 mutex_lock(&anslcd_mutex); 181 anslcd_write_byte_ctrl ( 0x38 ); 182 anslcd_write_byte_ctrl ( 0x0c ); 183 anslcd_write_byte_ctrl ( 0x06 ); 184 anslcd_write_byte_ctrl ( 0x01 ); 185 anslcd_write_byte_ctrl ( 0x02 ); 186 for(a=0;a<80;a++) { 187 anslcd_write_byte_data(anslcd_logo[a]); 188 } 189 mutex_unlock(&anslcd_mutex); 190 return 0; 191 } 192 193 static void __exit 194 anslcd_exit(void) 195 { 196 misc_deregister(&anslcd_dev); 197 iounmap(anslcd_ptr); 198 } 199 200 module_init(anslcd_init); 201 module_exit(anslcd_exit); 202