File: /usr/src/linux/drivers/media/radio/miropcm20-rds.c

1     /* MiroSOUND PCM20 radio rds interface driver
2      * (c) 2001 Robert Siemer <Robert.Siemer@gmx.de>
3      * Thanks to Fred Seidel. See miropcm20-rds-core.c for further information.
4      */
5     
6     /* Revision history:
7      *
8      *   2001-04-18  Robert Siemer <Robert.Siemer@gmx.de>
9      *        separate file for user interface driver
10      */
11     
12     #include <linux/module.h>
13     #include <linux/init.h>
14     #include <linux/slab.h>
15     #include <asm/uaccess.h>
16     #include <linux/devfs_fs_kernel.h>
17     #include "miropcm20-rds-core.h"
18     
19     devfs_handle_t dfsh;
20     char * text_buffer;
21     static int rds_users = 0;
22     
23     
24     static int rds_f_open(struct inode *in, struct file *fi)
25     {
26     	if(rds_users)
27     		return -EBUSY;
28     
29     	if ((text_buffer=kmalloc(66, GFP_KERNEL)) == 0) {
30     		printk(KERN_NOTICE "aci-rds: Out of memory by open()...\n");
31     		return -ENOMEM;
32     	}
33     
34     	rds_users++;
35     	MOD_INC_USE_COUNT;
36     	return 0;
37     }
38     
39     static int rds_f_release(struct inode *in, struct file *fi)
40     {
41     	kfree(text_buffer);
42     
43     	rds_users--;
44     	MOD_DEC_USE_COUNT;
45     	return 0;
46     }
47     
48     static void print_matrix(char *ch, char out[])
49     {
50             int j;
51     
52     	for (j=7; j>=0; j--) {
53     		 out[7-j] = ((*ch >> j) & 0x1) + '0';
54     	}
55     }
56     
57     static ssize_t rds_f_read(struct file *file, char *buffer, size_t length, loff_t *offset)
58     {
59     //	i = sprintf(text_buffer, "length: %d, offset: %d\n", length, *offset);
60     
61     	char c;
62     	char bits[8];
63     
64     	current->state=TASK_UNINTERRUPTIBLE;
65     	schedule_timeout(2*HZ);
66     	aci_rds_cmd(RDS_STATUS, &c, 1);
67     	print_matrix(&c, bits);
68     	if (copy_to_user(buffer, bits, 8))
69     		return -EFAULT;
70     
71     /*	if ((c >> 3) & 1) {
72     		aci_rds_cmd(RDS_STATIONNAME, text_buffer+1, 8);
73     		text_buffer[0]  = ' ' ;
74     		text_buffer[9]  = '\n';
75     		return copy_to_user(buffer+8, text_buffer, 10) ? -EFAULT: 18;
76     	}
77     */
78     /*	if ((c >> 6) & 1) {
79     		aci_rds_cmd(RDS_PTYTATP, &c, 1);
80     		if ( c & 1)
81     			sprintf(text_buffer, " M");
82     		else
83     			sprintf(text_buffer, " S");
84     		if ((c >> 1) & 1)
85     			sprintf(text_buffer+2, " TA");
86     		else
87     			sprintf(text_buffer+2, " --");
88     		if ((c >> 7) & 1)
89     			sprintf(text_buffer+5, " TP");
90     		else
91     			sprintf(text_buffer+5, " --");
92     		sprintf(text_buffer+8, " %2d\n", (c >> 2) & 0x1f);
93     		return copy_to_user(buffer+8, text_buffer, 12) ? -EFAULT: 20;
94     	}
95     */
96     
97     	if ((c >> 4) & 1) {
98     		aci_rds_cmd(RDS_TEXT, text_buffer, 65);
99     		text_buffer[0]  = ' ' ;
100     		text_buffer[65] = '\n';
101     		return copy_to_user(buffer+8, text_buffer,66) ? -EFAULT : 66+8;
102     	} else {
103     		put_user('\n', buffer+8);
104     		return 9;
105     	}
106     }
107     
108     static struct file_operations rds_f_ops = {
109     	read:    rds_f_read,
110     	open:    rds_f_open,
111     	release: rds_f_release
112     };
113     
114     
115     static int __init miropcm20_rds_init(void)
116     {
117     	if ((dfsh = devfs_register(NULL, "v4l/rds/radiotext", 
118     				   DEVFS_FL_DEFAULT | DEVFS_FL_AUTO_DEVNUM,
119     				   0, 0, S_IRUGO | S_IFCHR, &rds_f_ops, NULL))
120     	    == NULL)
121     		goto devfs_register;
122     
123     	printk("miropcm20-rds: userinterface driver loaded.\n");
124     #if DEBUG
125     	printk("v4l-name: %s\n", devfs_get_name(pcm20_radio.devfs_handle, 0));
126     #endif
127     
128     	return 0;
129     
130      devfs_register:
131     	return -EINVAL;
132     }
133     
134     static void __exit miropcm20_rds_cleanup(void)
135     {
136     	devfs_unregister(dfsh);
137     }
138     
139     module_init(miropcm20_rds_init);
140     module_exit(miropcm20_rds_cleanup);
141