xref: /openbmc/linux/sound/aoa/soundbus/i2sbus/core.c (revision 6774def6)
1 /*
2  * i2sbus driver
3  *
4  * Copyright 2006-2008 Johannes Berg <johannes@sipsolutions.net>
5  *
6  * GPL v2, can be found in COPYING.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/pci.h>
12 #include <linux/interrupt.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/of_address.h>
15 #include <linux/of_irq.h>
16 
17 #include <sound/core.h>
18 
19 #include <asm/macio.h>
20 #include <asm/dbdma.h>
21 
22 #include "../soundbus.h"
23 #include "i2sbus.h"
24 
25 MODULE_LICENSE("GPL");
26 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
27 MODULE_DESCRIPTION("Apple Soundbus: I2S support");
28 
29 static int force;
30 module_param(force, int, 0444);
31 MODULE_PARM_DESC(force, "Force loading i2sbus even when"
32 			" no layout-id property is present");
33 
34 static struct of_device_id i2sbus_match[] = {
35 	{ .name = "i2s" },
36 	{ }
37 };
38 
39 MODULE_DEVICE_TABLE(of, i2sbus_match);
40 
41 static int alloc_dbdma_descriptor_ring(struct i2sbus_dev *i2sdev,
42 				       struct dbdma_command_mem *r,
43 				       int numcmds)
44 {
45 	/* one more for rounding, one for branch back, one for stop command */
46 	r->size = (numcmds + 3) * sizeof(struct dbdma_cmd);
47 	/* We use the PCI APIs for now until the generic one gets fixed
48 	 * enough or until we get some macio-specific versions
49 	 */
50 	r->space = dma_zalloc_coherent(&macio_get_pci_dev(i2sdev->macio)->dev,
51 				       r->size, &r->bus_addr, GFP_KERNEL);
52 	if (!r->space)
53 		return -ENOMEM;
54 
55 	r->cmds = (void*)DBDMA_ALIGN(r->space);
56 	r->bus_cmd_start = r->bus_addr +
57 			   (dma_addr_t)((char*)r->cmds - (char*)r->space);
58 
59 	return 0;
60 }
61 
62 static void free_dbdma_descriptor_ring(struct i2sbus_dev *i2sdev,
63 				       struct dbdma_command_mem *r)
64 {
65 	if (!r->space) return;
66 
67 	dma_free_coherent(&macio_get_pci_dev(i2sdev->macio)->dev,
68 			    r->size, r->space, r->bus_addr);
69 }
70 
71 static void i2sbus_release_dev(struct device *dev)
72 {
73 	struct i2sbus_dev *i2sdev;
74 	int i;
75 
76 	i2sdev = container_of(dev, struct i2sbus_dev, sound.ofdev.dev);
77 
78  	if (i2sdev->intfregs) iounmap(i2sdev->intfregs);
79  	if (i2sdev->out.dbdma) iounmap(i2sdev->out.dbdma);
80  	if (i2sdev->in.dbdma) iounmap(i2sdev->in.dbdma);
81 	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
82 		if (i2sdev->allocated_resource[i])
83 			release_and_free_resource(i2sdev->allocated_resource[i]);
84 	free_dbdma_descriptor_ring(i2sdev, &i2sdev->out.dbdma_ring);
85 	free_dbdma_descriptor_ring(i2sdev, &i2sdev->in.dbdma_ring);
86 	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
87 		free_irq(i2sdev->interrupts[i], i2sdev);
88 	i2sbus_control_remove_dev(i2sdev->control, i2sdev);
89 	mutex_destroy(&i2sdev->lock);
90 	kfree(i2sdev);
91 }
92 
93 static irqreturn_t i2sbus_bus_intr(int irq, void *devid)
94 {
95 	struct i2sbus_dev *dev = devid;
96 	u32 intreg;
97 
98 	spin_lock(&dev->low_lock);
99 	intreg = in_le32(&dev->intfregs->intr_ctl);
100 
101 	/* acknowledge interrupt reasons */
102 	out_le32(&dev->intfregs->intr_ctl, intreg);
103 
104 	spin_unlock(&dev->low_lock);
105 
106 	return IRQ_HANDLED;
107 }
108 
109 
110 /*
111  * XXX FIXME: We test the layout_id's here to get the proper way of
112  * mapping in various registers, thanks to bugs in Apple device-trees.
113  * We could instead key off the machine model and the name of the i2s
114  * node (i2s-a). This we'll do when we move it all to macio_asic.c
115  * and have that export items for each sub-node too.
116  */
117 static int i2sbus_get_and_fixup_rsrc(struct device_node *np, int index,
118 				     int layout, struct resource *res)
119 {
120 	struct device_node *parent;
121 	int pindex, rc = -ENXIO;
122 	const u32 *reg;
123 
124 	/* Machines with layout 76 and 36 (K2 based) have a weird device
125 	 * tree what we need to special case.
126 	 * Normal machines just fetch the resource from the i2s-X node.
127 	 * Darwin further divides normal machines into old and new layouts
128 	 * with a subtely different code path but that doesn't seem necessary
129 	 * in practice, they just bloated it. In addition, even on our K2
130 	 * case the i2s-modem node, if we ever want to handle it, uses the
131 	 * normal layout
132 	 */
133 	if (layout != 76 && layout != 36)
134 		return of_address_to_resource(np, index, res);
135 
136 	parent = of_get_parent(np);
137 	pindex = (index == aoa_resource_i2smmio) ? 0 : 1;
138 	rc = of_address_to_resource(parent, pindex, res);
139 	if (rc)
140 		goto bail;
141 	reg = of_get_property(np, "reg", NULL);
142 	if (reg == NULL) {
143 		rc = -ENXIO;
144 		goto bail;
145 	}
146 	res->start += reg[index * 2];
147 	res->end = res->start + reg[index * 2 + 1] - 1;
148  bail:
149 	of_node_put(parent);
150 	return rc;
151 }
152 
153 /* FIXME: look at device node refcounting */
154 static int i2sbus_add_dev(struct macio_dev *macio,
155 			  struct i2sbus_control *control,
156 			  struct device_node *np)
157 {
158 	struct i2sbus_dev *dev;
159 	struct device_node *child = NULL, *sound = NULL;
160 	struct resource *r;
161 	int i, layout = 0, rlen, ok = force;
162 	static const char *rnames[] = { "i2sbus: %s (control)",
163 					"i2sbus: %s (tx)",
164 					"i2sbus: %s (rx)" };
165 	static irq_handler_t ints[] = {
166 		i2sbus_bus_intr,
167 		i2sbus_tx_intr,
168 		i2sbus_rx_intr
169 	};
170 
171 	if (strlen(np->name) != 5)
172 		return 0;
173 	if (strncmp(np->name, "i2s-", 4))
174 		return 0;
175 
176 	dev = kzalloc(sizeof(struct i2sbus_dev), GFP_KERNEL);
177 	if (!dev)
178 		return 0;
179 
180 	i = 0;
181 	while ((child = of_get_next_child(np, child))) {
182 		if (strcmp(child->name, "sound") == 0) {
183 			i++;
184 			sound = child;
185 		}
186 	}
187 	if (i == 1) {
188 		const u32 *id = of_get_property(sound, "layout-id", NULL);
189 
190 		if (id) {
191 			layout = *id;
192 			snprintf(dev->sound.modalias, 32,
193 				 "sound-layout-%d", layout);
194 			ok = 1;
195 		} else {
196 			id = of_get_property(sound, "device-id", NULL);
197 			/*
198 			 * We probably cannot handle all device-id machines,
199 			 * so restrict to those we do handle for now.
200 			 */
201 			if (id && (*id == 22 || *id == 14 || *id == 35 ||
202 				   *id == 44)) {
203 				snprintf(dev->sound.modalias, 32,
204 					 "aoa-device-id-%d", *id);
205 				ok = 1;
206 				layout = -1;
207 			}
208 		}
209 	}
210 	/* for the time being, until we can handle non-layout-id
211 	 * things in some fabric, refuse to attach if there is no
212 	 * layout-id property or we haven't been forced to attach.
213 	 * When there are two i2s busses and only one has a layout-id,
214 	 * then this depends on the order, but that isn't important
215 	 * either as the second one in that case is just a modem. */
216 	if (!ok) {
217 		kfree(dev);
218 		return -ENODEV;
219 	}
220 
221 	mutex_init(&dev->lock);
222 	spin_lock_init(&dev->low_lock);
223 	dev->sound.ofdev.archdata.dma_mask = macio->ofdev.archdata.dma_mask;
224 	dev->sound.ofdev.dev.of_node = np;
225 	dev->sound.ofdev.dev.dma_mask = &dev->sound.ofdev.archdata.dma_mask;
226 	dev->sound.ofdev.dev.parent = &macio->ofdev.dev;
227 	dev->sound.ofdev.dev.release = i2sbus_release_dev;
228 	dev->sound.attach_codec = i2sbus_attach_codec;
229 	dev->sound.detach_codec = i2sbus_detach_codec;
230 	dev->sound.pcmid = -1;
231 	dev->macio = macio;
232 	dev->control = control;
233 	dev->bus_number = np->name[4] - 'a';
234 	INIT_LIST_HEAD(&dev->sound.codec_list);
235 
236 	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
237 		dev->interrupts[i] = -1;
238 		snprintf(dev->rnames[i], sizeof(dev->rnames[i]),
239 			 rnames[i], np->name);
240 	}
241 	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
242 		int irq = irq_of_parse_and_map(np, i);
243 		if (request_irq(irq, ints[i], 0, dev->rnames[i], dev))
244 			goto err;
245 		dev->interrupts[i] = irq;
246 	}
247 
248 
249 	/* Resource handling is problematic as some device-trees contain
250 	 * useless crap (ugh ugh ugh). We work around that here by calling
251 	 * specific functions for calculating the appropriate resources.
252 	 *
253 	 * This will all be moved to macio_asic.c at one point
254 	 */
255 	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
256 		if (i2sbus_get_and_fixup_rsrc(np,i,layout,&dev->resources[i]))
257 			goto err;
258 		/* If only we could use our resource dev->resources[i]...
259 		 * but request_resource doesn't know about parents and
260 		 * contained resources...
261 		 */
262 		dev->allocated_resource[i] =
263 			request_mem_region(dev->resources[i].start,
264 					   resource_size(&dev->resources[i]),
265 					   dev->rnames[i]);
266 		if (!dev->allocated_resource[i]) {
267 			printk(KERN_ERR "i2sbus: failed to claim resource %d!\n", i);
268 			goto err;
269 		}
270 	}
271 
272 	r = &dev->resources[aoa_resource_i2smmio];
273 	rlen = resource_size(r);
274 	if (rlen < sizeof(struct i2s_interface_regs))
275 		goto err;
276 	dev->intfregs = ioremap(r->start, rlen);
277 
278 	r = &dev->resources[aoa_resource_txdbdma];
279 	rlen = resource_size(r);
280 	if (rlen < sizeof(struct dbdma_regs))
281 		goto err;
282 	dev->out.dbdma = ioremap(r->start, rlen);
283 
284 	r = &dev->resources[aoa_resource_rxdbdma];
285 	rlen = resource_size(r);
286 	if (rlen < sizeof(struct dbdma_regs))
287 		goto err;
288 	dev->in.dbdma = ioremap(r->start, rlen);
289 
290 	if (!dev->intfregs || !dev->out.dbdma || !dev->in.dbdma)
291 		goto err;
292 
293 	if (alloc_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring,
294 					MAX_DBDMA_COMMANDS))
295 		goto err;
296 	if (alloc_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring,
297 					MAX_DBDMA_COMMANDS))
298 		goto err;
299 
300 	if (i2sbus_control_add_dev(dev->control, dev)) {
301 		printk(KERN_ERR "i2sbus: control layer didn't like bus\n");
302 		goto err;
303 	}
304 
305 	if (soundbus_add_one(&dev->sound)) {
306 		printk(KERN_DEBUG "i2sbus: device registration error!\n");
307 		goto err;
308 	}
309 
310 	/* enable this cell */
311 	i2sbus_control_cell(dev->control, dev, 1);
312 	i2sbus_control_enable(dev->control, dev);
313 	i2sbus_control_clock(dev->control, dev, 1);
314 
315 	return 1;
316  err:
317 	for (i=0;i<3;i++)
318 		if (dev->interrupts[i] != -1)
319 			free_irq(dev->interrupts[i], dev);
320 	free_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring);
321 	free_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring);
322 	if (dev->intfregs) iounmap(dev->intfregs);
323 	if (dev->out.dbdma) iounmap(dev->out.dbdma);
324 	if (dev->in.dbdma) iounmap(dev->in.dbdma);
325 	for (i=0;i<3;i++)
326 		if (dev->allocated_resource[i])
327 			release_and_free_resource(dev->allocated_resource[i]);
328 	mutex_destroy(&dev->lock);
329 	kfree(dev);
330 	return 0;
331 }
332 
333 static int i2sbus_probe(struct macio_dev* dev, const struct of_device_id *match)
334 {
335 	struct device_node *np = NULL;
336 	int got = 0, err;
337 	struct i2sbus_control *control = NULL;
338 
339 	err = i2sbus_control_init(dev, &control);
340 	if (err)
341 		return err;
342 	if (!control) {
343 		printk(KERN_ERR "i2sbus_control_init API breakage\n");
344 		return -ENODEV;
345 	}
346 
347 	while ((np = of_get_next_child(dev->ofdev.dev.of_node, np))) {
348 		if (of_device_is_compatible(np, "i2sbus") ||
349 		    of_device_is_compatible(np, "i2s-modem")) {
350 			got += i2sbus_add_dev(dev, control, np);
351 		}
352 	}
353 
354 	if (!got) {
355 		/* found none, clean up */
356 		i2sbus_control_destroy(control);
357 		return -ENODEV;
358 	}
359 
360 	dev_set_drvdata(&dev->ofdev.dev, control);
361 
362 	return 0;
363 }
364 
365 static int i2sbus_remove(struct macio_dev* dev)
366 {
367 	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
368 	struct i2sbus_dev *i2sdev, *tmp;
369 
370 	list_for_each_entry_safe(i2sdev, tmp, &control->list, item)
371 		soundbus_remove_one(&i2sdev->sound);
372 
373 	return 0;
374 }
375 
376 #ifdef CONFIG_PM
377 static int i2sbus_suspend(struct macio_dev* dev, pm_message_t state)
378 {
379 	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
380 	struct codec_info_item *cii;
381 	struct i2sbus_dev* i2sdev;
382 	int err, ret = 0;
383 
384 	list_for_each_entry(i2sdev, &control->list, item) {
385 		/* Notify Alsa */
386 		if (i2sdev->sound.pcm) {
387 			/* Suspend PCM streams */
388 			snd_pcm_suspend_all(i2sdev->sound.pcm);
389 		}
390 
391 		/* Notify codecs */
392 		list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
393 			err = 0;
394 			if (cii->codec->suspend)
395 				err = cii->codec->suspend(cii, state);
396 			if (err)
397 				ret = err;
398 		}
399 
400 		/* wait until streams are stopped */
401 		i2sbus_wait_for_stop_both(i2sdev);
402 	}
403 
404 	return ret;
405 }
406 
407 static int i2sbus_resume(struct macio_dev* dev)
408 {
409 	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
410 	struct codec_info_item *cii;
411 	struct i2sbus_dev* i2sdev;
412 	int err, ret = 0;
413 
414 	list_for_each_entry(i2sdev, &control->list, item) {
415 		/* reset i2s bus format etc. */
416 		i2sbus_pcm_prepare_both(i2sdev);
417 
418 		/* Notify codecs so they can re-initialize */
419 		list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
420 			err = 0;
421 			if (cii->codec->resume)
422 				err = cii->codec->resume(cii);
423 			if (err)
424 				ret = err;
425 		}
426 	}
427 
428 	return ret;
429 }
430 #endif /* CONFIG_PM */
431 
432 static int i2sbus_shutdown(struct macio_dev* dev)
433 {
434 	return 0;
435 }
436 
437 static struct macio_driver i2sbus_drv = {
438 	.driver = {
439 		.name = "soundbus-i2s",
440 		.owner = THIS_MODULE,
441 		.of_match_table = i2sbus_match,
442 	},
443 	.probe = i2sbus_probe,
444 	.remove = i2sbus_remove,
445 #ifdef CONFIG_PM
446 	.suspend = i2sbus_suspend,
447 	.resume = i2sbus_resume,
448 #endif
449 	.shutdown = i2sbus_shutdown,
450 };
451 
452 static int __init soundbus_i2sbus_init(void)
453 {
454 	return macio_register_driver(&i2sbus_drv);
455 }
456 
457 static void __exit soundbus_i2sbus_exit(void)
458 {
459 	macio_unregister_driver(&i2sbus_drv);
460 }
461 
462 module_init(soundbus_i2sbus_init);
463 module_exit(soundbus_i2sbus_exit);
464