ALSA: fix excessive background noise introduced by OSS emulation rate shrink
[linux-2.6.git] / sound / drivers / mpu401 / mpu401.c
1 /*
2  *  Driver for generic MPU-401 boards (UART mode only)
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *  Copyright (c) 2004 by Castet Matthieu <castet.matthieu@free.fr>
5  *
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  *   This program is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with this program; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  *
21  */
22
23 #include <linux/init.h>
24 #include <linux/pnp.h>
25 #include <linux/err.h>
26 #include <linux/platform_device.h>
27 #include <linux/moduleparam.h>
28 #include <sound/core.h>
29 #include <sound/mpu401.h>
30 #include <sound/initval.h>
31
32 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
33 MODULE_DESCRIPTION("MPU-401 UART");
34 MODULE_LICENSE("GPL");
35
36 static int index[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = -2}; /* exclude the first card */
37 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
38 static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE;  /* Enable this card */
39 #ifdef CONFIG_PNP
40 static int pnp[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
41 #endif
42 static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT;     /* MPU-401 port number */
43 static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ;        /* MPU-401 IRQ */
44 static int uart_enter[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
45
46 module_param_array(index, int, NULL, 0444);
47 MODULE_PARM_DESC(index, "Index value for MPU-401 device.");
48 module_param_array(id, charp, NULL, 0444);
49 MODULE_PARM_DESC(id, "ID string for MPU-401 device.");
50 module_param_array(enable, bool, NULL, 0444);
51 MODULE_PARM_DESC(enable, "Enable MPU-401 device.");
52 #ifdef CONFIG_PNP
53 module_param_array(pnp, bool, NULL, 0444);
54 MODULE_PARM_DESC(pnp, "PnP detection for MPU-401 device.");
55 #endif
56 module_param_array(port, long, NULL, 0444);
57 MODULE_PARM_DESC(port, "Port # for MPU-401 device.");
58 module_param_array(irq, int, NULL, 0444);
59 MODULE_PARM_DESC(irq, "IRQ # for MPU-401 device.");
60 module_param_array(uart_enter, bool, NULL, 0444);
61 MODULE_PARM_DESC(uart_enter, "Issue UART_ENTER command at open.");
62
63 static struct platform_device *platform_devices[SNDRV_CARDS];
64 static int pnp_registered;
65 static unsigned int snd_mpu401_devices;
66
67 static int snd_mpu401_create(int dev, struct snd_card **rcard)
68 {
69         struct snd_card *card;
70         int err;
71
72         if (!uart_enter[dev])
73                 snd_printk(KERN_ERR "the uart_enter option is obsolete; remove it\n");
74
75         *rcard = NULL;
76         card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
77         if (card == NULL)
78                 return -ENOMEM;
79         strcpy(card->driver, "MPU-401 UART");
80         strcpy(card->shortname, card->driver);
81         sprintf(card->longname, "%s at %#lx, ", card->shortname, port[dev]);
82         if (irq[dev] >= 0) {
83                 sprintf(card->longname + strlen(card->longname), "irq %d", irq[dev]);
84         } else {
85                 strcat(card->longname, "polled");
86         }
87
88         err = snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port[dev], 0,
89                                   irq[dev], irq[dev] >= 0 ? IRQF_DISABLED : 0,
90                                   NULL);
91         if (err < 0) {
92                 printk(KERN_ERR "MPU401 not detected at 0x%lx\n", port[dev]);
93                 goto _err;
94         }
95
96         *rcard = card;
97         return 0;
98
99  _err:
100         snd_card_free(card);
101         return err;
102 }
103
104 static int __devinit snd_mpu401_probe(struct platform_device *devptr)
105 {
106         int dev = devptr->id;
107         int err;
108         struct snd_card *card;
109
110         if (port[dev] == SNDRV_AUTO_PORT) {
111                 snd_printk(KERN_ERR "specify port\n");
112                 return -EINVAL;
113         }
114         if (irq[dev] == SNDRV_AUTO_IRQ) {
115                 snd_printk(KERN_ERR "specify or disable IRQ\n");
116                 return -EINVAL;
117         }
118         err = snd_mpu401_create(dev, &card);
119         if (err < 0)
120                 return err;
121         snd_card_set_dev(card, &devptr->dev);
122         if ((err = snd_card_register(card)) < 0) {
123                 snd_card_free(card);
124                 return err;
125         }
126         platform_set_drvdata(devptr, card);
127         return 0;
128 }
129
130 static int __devexit snd_mpu401_remove(struct platform_device *devptr)
131 {
132         snd_card_free(platform_get_drvdata(devptr));
133         platform_set_drvdata(devptr, NULL);
134         return 0;
135 }
136
137 #define SND_MPU401_DRIVER       "snd_mpu401"
138
139 static struct platform_driver snd_mpu401_driver = {
140         .probe          = snd_mpu401_probe,
141         .remove         = __devexit_p(snd_mpu401_remove),
142         .driver         = {
143                 .name   = SND_MPU401_DRIVER
144         },
145 };
146
147
148 #ifdef CONFIG_PNP
149
150 #define IO_EXTENT 2
151
152 static struct pnp_device_id snd_mpu401_pnpids[] = {
153         { .id = "PNPb006" },
154         { .id = "" }
155 };
156
157 MODULE_DEVICE_TABLE(pnp, snd_mpu401_pnpids);
158
159 static int __devinit snd_mpu401_pnp(int dev, struct pnp_dev *device,
160                                  const struct pnp_device_id *id)
161 {
162         if (!pnp_port_valid(device, 0) ||
163             pnp_port_flags(device, 0) & IORESOURCE_DISABLED) {
164                 snd_printk(KERN_ERR "no PnP port\n");
165                 return -ENODEV;
166         }
167         if (pnp_port_len(device, 0) < IO_EXTENT) {
168                 snd_printk(KERN_ERR "PnP port length is %llu, expected %d\n",
169                            (unsigned long long)pnp_port_len(device, 0),
170                            IO_EXTENT);
171                 return -ENODEV;
172         }
173         port[dev] = pnp_port_start(device, 0);
174
175         if (!pnp_irq_valid(device, 0) ||
176             pnp_irq_flags(device, 0) & IORESOURCE_DISABLED) {
177                 snd_printk(KERN_WARNING "no PnP irq, using polling\n");
178                 irq[dev] = -1;
179         } else {
180                 irq[dev] = pnp_irq(device, 0);
181         }
182         return 0;
183 }
184
185 static int __devinit snd_mpu401_pnp_probe(struct pnp_dev *pnp_dev,
186                                           const struct pnp_device_id *id)
187 {
188         static int dev;
189         struct snd_card *card;
190         int err;
191
192         for ( ; dev < SNDRV_CARDS; ++dev) {
193                 if (!enable[dev] || !pnp[dev])
194                         continue;
195                 err = snd_mpu401_pnp(dev, pnp_dev, id);
196                 if (err < 0)
197                         return err;
198                 err = snd_mpu401_create(dev, &card);
199                 if (err < 0)
200                         return err;
201                 if ((err = snd_card_register(card)) < 0) {
202                         snd_card_free(card);
203                         return err;
204                 }
205                 snd_card_set_dev(card, &pnp_dev->dev);
206                 pnp_set_drvdata(pnp_dev, card);
207                 snd_mpu401_devices++;
208                 ++dev;
209                 return 0;
210         }
211         return -ENODEV;
212 }
213
214 static void __devexit snd_mpu401_pnp_remove(struct pnp_dev *dev)
215 {
216         struct snd_card *card = (struct snd_card *) pnp_get_drvdata(dev);
217
218         snd_card_disconnect(card);
219         snd_card_free_when_closed(card);
220 }
221
222 static struct pnp_driver snd_mpu401_pnp_driver = {
223         .name = "mpu401",
224         .id_table = snd_mpu401_pnpids,
225         .probe = snd_mpu401_pnp_probe,
226         .remove = __devexit_p(snd_mpu401_pnp_remove),
227 };
228 #else
229 static struct pnp_driver snd_mpu401_pnp_driver;
230 #endif
231
232 static void snd_mpu401_unregister_all(void)
233 {
234         int i;
235
236         if (pnp_registered)
237                 pnp_unregister_driver(&snd_mpu401_pnp_driver);
238         for (i = 0; i < ARRAY_SIZE(platform_devices); ++i)
239                 platform_device_unregister(platform_devices[i]);
240         platform_driver_unregister(&snd_mpu401_driver);
241 }
242
243 static int __init alsa_card_mpu401_init(void)
244 {
245         int i, err;
246
247         if ((err = platform_driver_register(&snd_mpu401_driver)) < 0)
248                 return err;
249
250         for (i = 0; i < SNDRV_CARDS; i++) {
251                 struct platform_device *device;
252                 if (! enable[i])
253                         continue;
254 #ifdef CONFIG_PNP
255                 if (pnp[i])
256                         continue;
257 #endif
258                 device = platform_device_register_simple(SND_MPU401_DRIVER,
259                                                          i, NULL, 0);
260                 if (IS_ERR(device))
261                         continue;
262                 if (!platform_get_drvdata(device)) {
263                         platform_device_unregister(device);
264                         continue;
265                 }
266                 platform_devices[i] = device;
267                 snd_mpu401_devices++;
268         }
269         err = pnp_register_driver(&snd_mpu401_pnp_driver);
270         if (!err)
271                 pnp_registered = 1;
272
273         if (!snd_mpu401_devices) {
274 #ifdef MODULE
275                 printk(KERN_ERR "MPU-401 device not found or device busy\n");
276 #endif
277                 snd_mpu401_unregister_all();
278                 return -ENODEV;
279         }
280         return 0;
281 }
282
283 static void __exit alsa_card_mpu401_exit(void)
284 {
285         snd_mpu401_unregister_all();
286 }
287
288 module_init(alsa_card_mpu401_init)
289 module_exit(alsa_card_mpu401_exit)