Merge branch 'timers-for-linus-migration' of git://git.kernel.org/pub/scm/linux/kerne...
[deliverable/linux.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 < 0)
168 return -EINVAL;
169
170 if (!count) {
171 dac_audio_sync();
172 return 0;
173 }
174
175 free = buffer_begin - buffer_end;
176
177 if (free < 0)
178 free += BUFFER_SIZE;
179 if ((free == 0) && (empty))
180 free = BUFFER_SIZE;
181 if (count > free)
182 count = free;
183 if (buffer_begin > buffer_end) {
184 if (copy_from_user((void *)buffer_end, buf, count))
185 return -EFAULT;
186
187 buffer_end += count;
188 } else {
189 nbytes = data_buffer + BUFFER_SIZE - buffer_end;
190 if (nbytes > count) {
191 if (copy_from_user((void *)buffer_end, buf, count))
192 return -EFAULT;
193 buffer_end += count;
194 } else {
195 if (copy_from_user((void *)buffer_end, buf, nbytes))
196 return -EFAULT;
197 if (copy_from_user
198 ((void *)data_buffer, buf + nbytes, count - nbytes))
199 return -EFAULT;
200 buffer_end = data_buffer + count - nbytes;
201 }
202 }
203
204 if (empty) {
205 empty = 0;
206 dac_audio_start_timer();
207 }
208
209 return count;
210 }
211
212 static ssize_t dac_audio_read(struct file *file, char *buf, size_t count,
213 loff_t * ppos)
214 {
215 return -EINVAL;
216 }
217
218 static int dac_audio_open(struct inode *inode, struct file *file)
219 {
220 if (file->f_mode & FMODE_READ)
221 return -ENODEV;
222 if (in_use)
223 return -EBUSY;
224
225 in_use = 1;
226
227 dac_audio_start();
228
229 return 0;
230 }
231
232 static int dac_audio_release(struct inode *inode, struct file *file)
233 {
234 dac_audio_sync();
235 dac_audio_stop();
236 in_use = 0;
237
238 return 0;
239 }
240
241 const struct file_operations dac_audio_fops = {
242 .read = dac_audio_read,
243 .write = dac_audio_write,
244 .ioctl = dac_audio_ioctl,
245 .open = dac_audio_open,
246 .release = dac_audio_release,
247 };
248
249 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
250 {
251 if (!empty) {
252 sh_dac_output(*buffer_begin, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
253 buffer_begin++;
254
255 if (buffer_begin == data_buffer + BUFFER_SIZE)
256 buffer_begin = data_buffer;
257 if (buffer_begin == buffer_end)
258 empty = 1;
259 }
260
261 if (!empty)
262 hrtimer_start(&hrtimer, wakeups_per_second, HRTIMER_MODE_REL);
263
264 return HRTIMER_NORESTART;
265 }
266
267 static int __init dac_audio_init(void)
268 {
269 if ((device_major = register_sound_dsp(&dac_audio_fops, -1)) < 0) {
270 printk(KERN_ERR "Cannot register dsp device");
271 return device_major;
272 }
273
274 in_use = 0;
275
276 data_buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
277 if (data_buffer == NULL)
278 return -ENOMEM;
279
280 dac_audio_reset();
281 rate = 8000;
282 dac_audio_set_rate();
283
284 /* Today: High Resolution Timer driven DAC playback.
285 * The timer callback gets called once per sample. Ouch.
286 *
287 * Future: A much better approach would be to use the
288 * SH7720 CMT+DMAC+DAC hardware combination like this:
289 * - Program sample rate using CMT0 or CMT1
290 * - Program DMAC to use CMT for timing and output to DAC
291 * - Play sound using DMAC, let CPU sleep.
292 * - While at it, rewrite this driver to use ALSA.
293 */
294
295 hrtimer_init(&hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
296 hrtimer.function = sh_dac_audio_timer;
297
298 return 0;
299 }
300
301 static void __exit dac_audio_exit(void)
302 {
303 unregister_sound_dsp(device_major);
304 kfree((void *)data_buffer);
305 }
306
307 module_init(dac_audio_init);
308 module_exit(dac_audio_exit);
309
310 MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
311 MODULE_DESCRIPTION("SH DAC sound driver");
312 MODULE_LICENSE("GPL");
This page took 0.163707 seconds and 6 git commands to generate.