core.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * i2sbus driver
  4 *
  5 * Copyright 2006-2008 Johannes Berg <johannes@sipsolutions.net>
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/slab.h>
 10#include <linux/pci.h>
 11#include <linux/interrupt.h>
 12#include <linux/dma-mapping.h>
 13#include <linux/of.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
 25MODULE_LICENSE("GPL");
 26MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
 27MODULE_DESCRIPTION("Apple Soundbus: I2S support");
 28
 29static int force;
 30module_param(force, int, 0444);
 31MODULE_PARM_DESC(force, "Force loading i2sbus even when"
 32			" no layout-id property is present");
 33
 34static const struct of_device_id i2sbus_match[] = {
 35	{ .name = "i2s" },
 36	{ }
 37};
 38
 39MODULE_DEVICE_TABLE(of, i2sbus_match);
 40
 41static 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_alloc_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
 62static 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
 71static 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	iounmap(i2sdev->intfregs);
 78	iounmap(i2sdev->out.dbdma);
 79	iounmap(i2sdev->in.dbdma);
 80	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
 81		release_and_free_resource(i2sdev->allocated_resource[i]);
 82	free_dbdma_descriptor_ring(i2sdev, &i2sdev->out.dbdma_ring);
 83	free_dbdma_descriptor_ring(i2sdev, &i2sdev->in.dbdma_ring);
 84	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
 85		free_irq(i2sdev->interrupts[i], i2sdev);
 86	i2sbus_control_remove_dev(i2sdev->control, i2sdev);
 87	mutex_destroy(&i2sdev->lock);
 88	kfree(i2sdev);
 89}
 90
 91static irqreturn_t i2sbus_bus_intr(int irq, void *devid)
 92{
 93	struct i2sbus_dev *dev = devid;
 94	u32 intreg;
 95
 96	guard(spinlock)(&dev->low_lock);
 97	intreg = in_le32(&dev->intfregs->intr_ctl);
 98
 99	/* acknowledge interrupt reasons */
100	out_le32(&dev->intfregs->intr_ctl, intreg);
101
102	return IRQ_HANDLED;
103}
104
105
106/*
107 * XXX FIXME: We test the layout_id's here to get the proper way of
108 * mapping in various registers, thanks to bugs in Apple device-trees.
109 * We could instead key off the machine model and the name of the i2s
110 * node (i2s-a). This we'll do when we move it all to macio_asic.c
111 * and have that export items for each sub-node too.
112 */
113static int i2sbus_get_and_fixup_rsrc(struct device_node *np, int index,
114				     int layout, struct resource *res)
115{
116	struct device_node *parent;
117	int pindex, rc = -ENXIO;
118	const u32 *reg;
119
120	/* Machines with layout 76 and 36 (K2 based) have a weird device
121	 * tree what we need to special case.
122	 * Normal machines just fetch the resource from the i2s-X node.
123	 * Darwin further divides normal machines into old and new layouts
124	 * with a subtely different code path but that doesn't seem necessary
125	 * in practice, they just bloated it. In addition, even on our K2
126	 * case the i2s-modem node, if we ever want to handle it, uses the
127	 * normal layout
128	 */
129	if (layout != 76 && layout != 36)
130		return of_address_to_resource(np, index, res);
131
132	parent = of_get_parent(np);
133	pindex = (index == aoa_resource_i2smmio) ? 0 : 1;
134	rc = of_address_to_resource(parent, pindex, res);
135	if (rc)
136		goto bail;
137	reg = of_get_property(np, "reg", NULL);
138	if (reg == NULL) {
139		rc = -ENXIO;
140		goto bail;
141	}
142	res->start += reg[index * 2];
143	res->end = res->start + reg[index * 2 + 1] - 1;
144 bail:
145	of_node_put(parent);
146	return rc;
147}
148
149/* Returns 1 if added, 0 for otherwise; don't return a negative value! */
150/* FIXME: look at device node refcounting */
151static int i2sbus_add_dev(struct macio_dev *macio,
152			  struct i2sbus_control *control,
153			  struct device_node *np)
154{
155	struct i2sbus_dev *dev;
156	struct device_node *child, *sound = NULL;
157	struct resource *r;
158	int i, layout = 0, rlen, ok = force;
159	char node_name[8];
160	static const char *rnames[] = { "i2sbus: %pOFn (control)",
161					"i2sbus: %pOFn (tx)",
162					"i2sbus: %pOFn (rx)" };
163	static const irq_handler_t ints[] = {
164		i2sbus_bus_intr,
165		i2sbus_tx_intr,
166		i2sbus_rx_intr
167	};
168
169	if (snprintf(node_name, sizeof(node_name), "%pOFn", np) != 5)
170		return 0;
171	if (strncmp(node_name, "i2s-", 4))
172		return 0;
173
174	dev = kzalloc(sizeof(struct i2sbus_dev), GFP_KERNEL);
175	if (!dev)
176		return 0;
177
178	i = 0;
179	for_each_child_of_node(np, child) {
180		if (of_node_name_eq(child, "sound")) {
181			i++;
182			sound = child;
183		}
184	}
185	if (i == 1) {
186		const u32 *id = of_get_property(sound, "layout-id", NULL);
187
188		if (id) {
189			layout = *id;
190			snprintf(dev->sound.modalias, 32,
191				 "sound-layout-%d", layout);
192			ok = 1;
193		} else {
194			id = of_get_property(sound, "device-id", NULL);
195			/*
196			 * We probably cannot handle all device-id machines,
197			 * so restrict to those we do handle for now.
198			 */
199			if (id && (*id == 22 || *id == 14 || *id == 35 ||
200				   *id == 31 || *id == 44)) {
201				snprintf(dev->sound.modalias, 32,
202					 "aoa-device-id-%d", *id);
203				ok = 1;
204				layout = -1;
205			}
206		}
207	}
208	/* for the time being, until we can handle non-layout-id
209	 * things in some fabric, refuse to attach if there is no
210	 * layout-id property or we haven't been forced to attach.
211	 * When there are two i2s busses and only one has a layout-id,
212	 * then this depends on the order, but that isn't important
213	 * either as the second one in that case is just a modem. */
214	if (!ok) {
215		kfree(dev);
216		return 0;
217	}
218
219	mutex_init(&dev->lock);
220	spin_lock_init(&dev->low_lock);
221	dev->sound.ofdev.archdata.dma_mask = macio->ofdev.archdata.dma_mask;
222	dev->sound.ofdev.dev.of_node = np;
223	dev->sound.ofdev.dev.dma_mask = &dev->sound.ofdev.archdata.dma_mask;
224	dev->sound.ofdev.dev.parent = &macio->ofdev.dev;
225	dev->sound.ofdev.dev.release = i2sbus_release_dev;
226	dev->sound.attach_codec = i2sbus_attach_codec;
227	dev->sound.detach_codec = i2sbus_detach_codec;
228	dev->sound.pcmid = -1;
229	dev->macio = macio;
230	dev->control = control;
231	dev->bus_number = node_name[4] - 'a';
232	INIT_LIST_HEAD(&dev->sound.codec_list);
233
234	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
235		dev->interrupts[i] = -1;
236		snprintf(dev->rnames[i], sizeof(dev->rnames[i]),
237			 rnames[i], np);
238	}
239	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
240		int irq = irq_of_parse_and_map(np, i);
241		if (request_irq(irq, ints[i], 0, dev->rnames[i], dev))
242			goto err;
243		dev->interrupts[i] = irq;
244	}
245
246
247	/* Resource handling is problematic as some device-trees contain
248	 * useless crap (ugh ugh ugh). We work around that here by calling
249	 * specific functions for calculating the appropriate resources.
250	 *
251	 * This will all be moved to macio_asic.c at one point
252	 */
253	for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
254		if (i2sbus_get_and_fixup_rsrc(np,i,layout,&dev->resources[i]))
255			goto err;
256		/* If only we could use our resource dev->resources[i]...
257		 * but request_resource doesn't know about parents and
258		 * contained resources...
259		 */
260		dev->allocated_resource[i] =
261			request_mem_region(dev->resources[i].start,
262					   resource_size(&dev->resources[i]),
263					   dev->rnames[i]);
264		if (!dev->allocated_resource[i]) {
265			printk(KERN_ERR "i2sbus: failed to claim resource %d!\n", i);
266			goto err;
267		}
268	}
269
270	r = &dev->resources[aoa_resource_i2smmio];
271	rlen = resource_size(r);
272	if (rlen < sizeof(struct i2s_interface_regs))
273		goto err;
274	dev->intfregs = ioremap(r->start, rlen);
275
276	r = &dev->resources[aoa_resource_txdbdma];
277	rlen = resource_size(r);
278	if (rlen < sizeof(struct dbdma_regs))
279		goto err;
280	dev->out.dbdma = ioremap(r->start, rlen);
281
282	r = &dev->resources[aoa_resource_rxdbdma];
283	rlen = resource_size(r);
284	if (rlen < sizeof(struct dbdma_regs))
285		goto err;
286	dev->in.dbdma = ioremap(r->start, rlen);
287
288	if (!dev->intfregs || !dev->out.dbdma || !dev->in.dbdma)
289		goto err;
290
291	if (alloc_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring,
292					MAX_DBDMA_COMMANDS))
293		goto err;
294	if (alloc_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring,
295					MAX_DBDMA_COMMANDS))
296		goto err;
297
298	if (i2sbus_control_add_dev(dev->control, dev)) {
299		printk(KERN_ERR "i2sbus: control layer didn't like bus\n");
300		goto err;
301	}
302
303	if (soundbus_add_one(&dev->sound)) {
304		printk(KERN_DEBUG "i2sbus: device registration error!\n");
305		if (dev->sound.ofdev.dev.kobj.state_initialized) {
306			soundbus_dev_put(&dev->sound);
307			return 0;
308		}
309		goto err;
310	}
311
312	/* enable this cell */
313	i2sbus_control_cell(dev->control, dev, 1);
314	i2sbus_control_enable(dev->control, dev);
315	i2sbus_control_clock(dev->control, dev, 1);
316
317	return 1;
318 err:
319	for (i=0;i<3;i++)
320		if (dev->interrupts[i] != -1)
321			free_irq(dev->interrupts[i], dev);
322	free_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring);
323	free_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring);
324	iounmap(dev->intfregs);
325	iounmap(dev->out.dbdma);
326	iounmap(dev->in.dbdma);
327	for (i=0;i<3;i++)
328		release_and_free_resource(dev->allocated_resource[i]);
329	mutex_destroy(&dev->lock);
330	kfree(dev);
331	return 0;
332}
333
334static int i2sbus_probe(struct macio_dev* dev, const struct of_device_id *match)
335{
336	struct device_node *np;
337	int got = 0, err;
338	struct i2sbus_control *control = NULL;
339
340	err = i2sbus_control_init(dev, &control);
341	if (err)
342		return err;
343	if (!control) {
344		printk(KERN_ERR "i2sbus_control_init API breakage\n");
345		return -ENODEV;
346	}
347
348	for_each_child_of_node(dev->ofdev.dev.of_node, np) {
349		if (of_device_is_compatible(np, "i2sbus") ||
350		    of_device_is_compatible(np, "i2s-modem")) {
351			got += i2sbus_add_dev(dev, control, np);
352		}
353	}
354
355	if (!got) {
356		/* found none, clean up */
357		i2sbus_control_destroy(control);
358		return -ENODEV;
359	}
360
361	dev_set_drvdata(&dev->ofdev.dev, control);
362
363	return 0;
364}
365
366static void i2sbus_remove(struct macio_dev *dev)
367{
368	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
369	struct i2sbus_dev *i2sdev, *tmp;
370
371	list_for_each_entry_safe(i2sdev, tmp, &control->list, item)
372		soundbus_remove_one(&i2sdev->sound);
373}
374
375#ifdef CONFIG_PM
376static int i2sbus_suspend(struct macio_dev* dev, pm_message_t state)
377{
378	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
379	struct codec_info_item *cii;
380	struct i2sbus_dev* i2sdev;
381	int err, ret = 0;
382
383	list_for_each_entry(i2sdev, &control->list, item) {
384		/* Notify codecs */
385		list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
386			err = 0;
387			if (cii->codec->suspend)
388				err = cii->codec->suspend(cii, state);
389			if (err)
390				ret = err;
391		}
392
393		/* wait until streams are stopped */
394		i2sbus_wait_for_stop_both(i2sdev);
395	}
396
397	return ret;
398}
399
400static int i2sbus_resume(struct macio_dev* dev)
401{
402	struct i2sbus_control *control = dev_get_drvdata(&dev->ofdev.dev);
403	struct codec_info_item *cii;
404	struct i2sbus_dev* i2sdev;
405	int err, ret = 0;
406
407	list_for_each_entry(i2sdev, &control->list, item) {
408		/* reset i2s bus format etc. */
409		i2sbus_pcm_prepare_both(i2sdev);
410
411		/* Notify codecs so they can re-initialize */
412		list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
413			err = 0;
414			if (cii->codec->resume)
415				err = cii->codec->resume(cii);
416			if (err)
417				ret = err;
418		}
419	}
420
421	return ret;
422}
423#endif /* CONFIG_PM */
424
425static int i2sbus_shutdown(struct macio_dev* dev)
426{
427	return 0;
428}
429
430static struct macio_driver i2sbus_drv = {
431	.driver = {
432		.name = "soundbus-i2s",
433		.owner = THIS_MODULE,
434		.of_match_table = i2sbus_match,
435	},
436	.probe = i2sbus_probe,
437	.remove = i2sbus_remove,
438#ifdef CONFIG_PM
439	.suspend = i2sbus_suspend,
440	.resume = i2sbus_resume,
441#endif
442	.shutdown = i2sbus_shutdown,
443};
444
445static int __init soundbus_i2sbus_init(void)
446{
447	return macio_register_driver(&i2sbus_drv);
448}
449
450static void __exit soundbus_i2sbus_exit(void)
451{
452	macio_unregister_driver(&i2sbus_drv);
453}
454
455module_init(soundbus_i2sbus_init);
456module_exit(soundbus_i2sbus_exit);