arch/mips/lasat/picvue_proc.c

   1 /*
   2  * Picvue PVC160206 display driver
   3  *
   4  * Brian Murphy <brian.murphy@eicon.com>
   5  *
   6  */
   7 #include <linux/kernel.h>
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/errno.h>
  11
  12 #include <linux/proc_fs.h>
  13 #include <linux/interrupt.h>
  14
  15 #include <linux/timer.h>
  16 #include <linux/mutex.h>
  17
  18 #include "picvue.h"
  19
  20 static DEFINE_MUTEX(pvc_mutex);
  21 static char pvc_lines[PVC_NLINES][PVC_LINELEN+1];
  22 static int pvc_linedata[PVC_NLINES];
  23 static struct proc_dir_entry *pvc_display_dir;
  24 static char *pvc_linename[PVC_NLINES] = {"line1", "line2"};
  25 #define DISPLAY_DIR_NAME "display"
  26 static int scroll_dir, scroll_interval;
  27
  28 static struct timer_list timer;
  29
  30 static void pvc_display(unsigned long data)
  31 {
  32         int i;
  33
  34         pvc_clear();
  35         for (i = 0; i < PVC_NLINES; i++)
  36                 pvc_write_string(pvc_lines[i], 0, i);
  37 }
  38
  39 static DECLARE_TASKLET(pvc_display_tasklet, &pvc_display, 0);
  40
  41 static int pvc_proc_read_line(char *page, char **start,
  42                              off_t off, int count,
  43                              int *eof, void *data)
  44 {
  45         char *origpage = page;
  46         int lineno = *(int *)data;
  47
  48         if (lineno < 0 || lineno > PVC_NLINES) {
  49                 printk(KERN_WARNING "proc_read_line: invalid lineno %d\n", lineno);
  50                 return 0;
  51         }
  52
  53         mutex_lock(&pvc_mutex);
  54         page += sprintf(page, "%s\n", pvc_lines[lineno]);
  55         mutex_unlock(&pvc_mutex);
  56
  57         return page - origpage;
  58 }
  59
  60 static int pvc_proc_write_line(struct file *file, const char *buffer,
  61                            unsigned long count, void *data)
  62 {
  63         int origcount = count;
  64         int lineno = *(int *)data;
  65
  66         if (lineno < 0 || lineno > PVC_NLINES) {
  67                 printk(KERN_WARNING "proc_write_line: invalid lineno %d\n",
  68                        lineno);
  69                 return origcount;
  70         }
  71
  72         if (count > PVC_LINELEN)
  73                 count = PVC_LINELEN;
  74
  75         if (buffer[count-1] == '\n')
  76                 count--;
  77
  78         mutex_lock(&pvc_mutex);
  79         strncpy(pvc_lines[lineno], buffer, count);
  80         pvc_lines[lineno][count] = '\0';
  81         mutex_unlock(&pvc_mutex);
  82
  83         tasklet_schedule(&pvc_display_tasklet);
  84
  85         return origcount;
  86 }
  87
  88 static int pvc_proc_write_scroll(struct file *file, const char *buffer,
  89                            unsigned long count, void *data)
  90 {
  91         int origcount = count;
  92         int cmd = simple_strtol(buffer, NULL, 10);
  93
  94         mutex_lock(&pvc_mutex);
  95         if (scroll_interval != 0)
  96                 del_timer(&timer);
  97
  98         if (cmd == 0) {
  99                 scroll_dir = 0;
 100                 scroll_interval = 0;
 101         } else {
 102                 if (cmd < 0) {
 103                         scroll_dir = -1;
 104                         scroll_interval = -cmd;
 105                 } else {
 106                         scroll_dir = 1;
 107                         scroll_interval = cmd;
 108                 }
 109                 add_timer(&timer);
 110         }
 111         mutex_unlock(&pvc_mutex);
 112
 113         return origcount;
 114 }
 115
 116 static int pvc_proc_read_scroll(char *page, char **start,
 117                              off_t off, int count,
 118                              int *eof, void *data)
 119 {
 120         char *origpage = page;
 121
 122         mutex_lock(&pvc_mutex);
 123         page += sprintf(page, "%d\n", scroll_dir * scroll_interval);
 124         mutex_unlock(&pvc_mutex);
 125
 126         return page - origpage;
 127 }
 128
 129
 130 void pvc_proc_timerfunc(unsigned long data)
 131 {
 132         if (scroll_dir < 0)
 133                 pvc_move(DISPLAY|RIGHT);
 134         else if (scroll_dir > 0)
 135                 pvc_move(DISPLAY|LEFT);
 136
 137         timer.expires = jiffies + scroll_interval;
 138         add_timer(&timer);
 139 }
 140
 141 static void pvc_proc_cleanup(void)
 142 {
 143         int i;
 144         for (i = 0; i < PVC_NLINES; i++)
 145                 remove_proc_entry(pvc_linename[i], pvc_display_dir);
 146         remove_proc_entry("scroll", pvc_display_dir);
 147         remove_proc_entry(DISPLAY_DIR_NAME, NULL);
 148
 149         del_timer(&timer);
 150 }
 151
 152 static int __init pvc_proc_init(void)
 153 {
 154         struct proc_dir_entry *proc_entry;
 155         int i;
 156
 157         pvc_display_dir = proc_mkdir(DISPLAY_DIR_NAME, NULL);
 158         if (pvc_display_dir == NULL)
 159                 goto error;
 160
 161         for (i = 0; i < PVC_NLINES; i++) {
 162                 strcpy(pvc_lines[i], "");
 163                 pvc_linedata[i] = i;
 164         }
 165         for (i = 0; i < PVC_NLINES; i++) {
 166                 proc_entry = create_proc_entry(pvc_linename[i], 0644,
 167                                                pvc_display_dir);
 168                 if (proc_entry == NULL)
 169                         goto error;
 170
 171                 proc_entry->read_proc = pvc_proc_read_line;
 172                 proc_entry->write_proc = pvc_proc_write_line;
 173                 proc_entry->data = &pvc_linedata[i];
 174         }
 175         proc_entry = create_proc_entry("scroll", 0644, pvc_display_dir);
 176         if (proc_entry == NULL)
 177                 goto error;
 178
 179         proc_entry->write_proc = pvc_proc_write_scroll;
 180         proc_entry->read_proc = pvc_proc_read_scroll;
 181
 182         init_timer(&timer);
 183         timer.function = pvc_proc_timerfunc;
 184
 185         return 0;
 186 error:
 187         pvc_proc_cleanup();
 188         return -ENOMEM;
 189 }
 190
 191 module_init(pvc_proc_init);
 192 module_exit(pvc_proc_cleanup);
 193 MODULE_LICENSE("GPL");