MIPS: Alchemy: change dbdma to accept physical memory addresses
[linux-2.6.git] / sound / oss / sh_dac_audio.c
1 /*
2  * sound/oss/sh_dac_audio.c
3  *
4  * SH DAC based sound :(
5  *
6  *  Copyright (C) 2004,2005  Andriy Skulysh
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  */
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/sched.h>
15 #include <linux/linkage.h>
16 #include <linux/slab.h>
17 #include <linux/fs.h>
18 #include <linux/sound.h>
19 #include <linux/soundcard.h>
20 #include <linux/interrupt.h>
21 #include <linux/hrtimer.h>
22 #include <asm/io.h>
23 #include <asm/uaccess.h>
24 #include <asm/irq.h>
25 #include <asm/delay.h>
26 #include <asm/clock.h>
27 #include <cpu/dac.h>
28 #include <asm/machvec.h>
29 #include <mach/hp6xx.h>
30 #include <asm/hd64461.h>
31
32 #define MODNAME "sh_dac_audio"
33
34 #define BUFFER_SIZE 48000
35
36 static int rate;
37 static int empty;
38 static char *data_buffer, *buffer_begin, *buffer_end;
39 static int in_use, device_major;
40 static struct hrtimer hrtimer;
41 static ktime_t wakeups_per_second;
42
43 static void dac_audio_start_timer(void)
44 {
45         hrtimer_start(&hrtimer, wakeups_per_second, HRTIMER_MODE_REL);
46 }
47
48 static void dac_audio_stop_timer(void)
49 {
50         hrtimer_cancel(&hrtimer);
51 }
52
53 static void dac_audio_reset(void)
54 {
55         dac_audio_stop_timer();
56         buffer_begin = buffer_end = data_buffer;
57         empty = 1;
58 }
59
60 static void dac_audio_sync(void)
61 {
62         while (!empty)
63                 schedule();
64 }
65
66 static void dac_audio_start(void)
67 {
68         if (mach_is_hp6xx()) {
69                 u16 v = __raw_readw(HD64461_GPADR);
70                 v &= ~HD64461_GPADR_SPEAKER;
71                 __raw_writew(v, HD64461_GPADR);
72         }
73
74         sh_dac_enable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
75 }
76 static void dac_audio_stop(void)
77 {
78         dac_audio_stop_timer();
79
80         if (mach_is_hp6xx()) {
81                 u16 v = __raw_readw(HD64461_GPADR);
82                 v |= HD64461_GPADR_SPEAKER;
83                 __raw_writew(v, HD64461_GPADR);
84         }
85
86         sh_dac_output(0, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
87         sh_dac_disable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
88 }
89
90 static void dac_audio_set_rate(void)
91 {
92         wakeups_per_second = ktime_set(0, 1000000000 / rate);
93 }
94
95 static int dac_audio_ioctl(struct inode *inode, struct file *file,
96                            unsigned int cmd, unsigned long arg)
97 {
98         int val;
99
100         switch (cmd) {
101         case OSS_GETVERSION:
102                 return put_user(SOUND_VERSION, (int *)arg);
103
104         case SNDCTL_DSP_SYNC:
105                 dac_audio_sync();
106                 return 0;
107
108         case SNDCTL_DSP_RESET:
109                 dac_audio_reset();
110                 return 0;
111
112         case SNDCTL_DSP_GETFMTS:
113                 return put_user(AFMT_U8, (int *)arg);
114
115         case SNDCTL_DSP_SETFMT:
116                 return put_user(AFMT_U8, (int *)arg);
117
118         case SNDCTL_DSP_NONBLOCK:
119                 spin_lock(&file->f_lock);
120                 file->f_flags |= O_NONBLOCK;
121                 spin_unlock(&file->f_lock);
122                 return 0;
123
124         case SNDCTL_DSP_GETCAPS:
125                 return 0;
126
127         case SOUND_PCM_WRITE_RATE:
128                 val = *(int *)arg;
129                 if (val > 0) {
130                         rate = val;
131                         dac_audio_set_rate();
132                 }
133                 return put_user(rate, (int *)arg);
134
135         case SNDCTL_DSP_STEREO:
136                 return put_user(0, (int *)arg);
137
138         case SOUND_PCM_WRITE_CHANNELS:
139                 return put_user(1, (int *)arg);
140
141         case SNDCTL_DSP_SETDUPLEX:
142                 return -EINVAL;
143
144         case SNDCTL_DSP_PROFILE:
145                 return -EINVAL;
146
147         case SNDCTL_DSP_GETBLKSIZE:
148                 return put_user(BUFFER_SIZE, (int *)arg);
149
150         case SNDCTL_DSP_SETFRAGMENT:
151                 return 0;
152
153         default:
154                 printk(KERN_ERR "sh_dac_audio: unimplemented ioctl=0x%x\n",
155                        cmd);
156                 return -EINVAL;
157         }
158         return -EINVAL;
159 }
160
161 static ssize_t dac_audio_write(struct file *file, const char *buf, size_t count,
162                                loff_t * ppos)
163 {
164         int free;
165         int nbytes;
166
167         if (!count) {
168                 dac_audio_sync();
169                 return 0;
170         }
171
172         free = buffer_begin - buffer_end;
173
174         if (free < 0)
175                 free += BUFFER_SIZE;
176         if ((free == 0) && (empty))
177                 free = BUFFER_SIZE;
178         if (count > free)
179                 count = free;
180         if (buffer_begin > buffer_end) {
181                 if (copy_from_user((void *)buffer_end, buf, count))
182                         return -EFAULT;
183
184                 buffer_end += count;
185         } else {
186                 nbytes = data_buffer + BUFFER_SIZE - buffer_end;
187                 if (nbytes > count) {
188                         if (copy_from_user((void *)buffer_end, buf, count))
189                                 return -EFAULT;
190                         buffer_end += count;
191                 } else {
192                         if (copy_from_user((void *)buffer_end, buf, nbytes))
193                                 return -EFAULT;
194                         if (copy_from_user
195                             ((void *)data_buffer, buf + nbytes, count - nbytes))
196                                 return -EFAULT;
197                         buffer_end = data_buffer + count - nbytes;
198                 }
199         }
200
201         if (empty) {
202                 empty = 0;
203                 dac_audio_start_timer();
204         }
205
206         return count;
207 }
208
209 static ssize_t dac_audio_read(struct file *file, char *buf, size_t count,
210                               loff_t * ppos)
211 {
212         return -EINVAL;
213 }
214
215 static int dac_audio_open(struct inode *inode, struct file *file)
216 {
217         if (file->f_mode & FMODE_READ)
218                 return -ENODEV;
219         if (in_use)
220                 return -EBUSY;
221
222         in_use = 1;
223
224         dac_audio_start();
225
226         return 0;
227 }
228
229 static int dac_audio_release(struct inode *inode, struct file *file)
230 {
231         dac_audio_sync();
232         dac_audio_stop();
233         in_use = 0;
234
235         return 0;
236 }
237
238 const struct file_operations dac_audio_fops = {
239       .read =           dac_audio_read,
240       .write =  dac_audio_write,
241       .ioctl =  dac_audio_ioctl,
242       .open =           dac_audio_open,
243       .release =        dac_audio_release,
244 };
245
246 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
247 {
248         if (!empty) {
249                 sh_dac_output(*buffer_begin, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
250                 buffer_begin++;
251
252                 if (buffer_begin == data_buffer + BUFFER_SIZE)
253                         buffer_begin = data_buffer;
254                 if (buffer_begin == buffer_end)
255                         empty = 1;
256         }
257
258         if (!empty)
259                 hrtimer_start(&hrtimer, wakeups_per_second, HRTIMER_MODE_REL);
260
261         return HRTIMER_NORESTART;
262 }
263
264 static int __init dac_audio_init(void)
265 {
266         if ((device_major = register_sound_dsp(&dac_audio_fops, -1)) < 0) {
267                 printk(KERN_ERR "Cannot register dsp device");
268                 return device_major;
269         }
270
271         in_use = 0;
272
273         data_buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
274         if (data_buffer == NULL)
275                 return -ENOMEM;
276
277         dac_audio_reset();
278         rate = 8000;
279         dac_audio_set_rate();
280
281         /* Today: High Resolution Timer driven DAC playback.
282          * The timer callback gets called once per sample. Ouch.
283          *
284          * Future: A much better approach would be to use the
285          * SH7720 CMT+DMAC+DAC hardware combination like this:
286          * - Program sample rate using CMT0 or CMT1
287          * - Program DMAC to use CMT for timing and output to DAC
288          * - Play sound using DMAC, let CPU sleep.
289          * - While at it, rewrite this driver to use ALSA.
290          */
291
292         hrtimer_init(&hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
293         hrtimer.function = sh_dac_audio_timer;
294
295         return 0;
296 }
297
298 static void __exit dac_audio_exit(void)
299 {
300         unregister_sound_dsp(device_major);
301         kfree((void *)data_buffer);
302 }
303
304 module_init(dac_audio_init);
305 module_exit(dac_audio_exit);
306
307 MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
308 MODULE_DESCRIPTION("SH DAC sound driver");
309 MODULE_LICENSE("GPL");