1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HD-audio core bus driver
4 */
5
6#include <linux/init.h>
7#include <linux/io.h>
8#include <linux/device.h>
9#include <linux/module.h>
10#include <linux/export.h>
11#include <sound/hdaudio.h>
12#include "local.h"
13#include "trace.h"
14
15static void snd_hdac_bus_process_unsol_events(struct work_struct *work);
16
17static const struct hdac_bus_ops default_ops = {
18 .command = snd_hdac_bus_send_cmd,
19 .get_response = snd_hdac_bus_get_response,
20 .link_power = snd_hdac_bus_link_power,
21};
22
23/**
24 * snd_hdac_bus_init - initialize a HD-audio bas bus
25 * @bus: the pointer to bus object
26 * @dev: device pointer
27 * @ops: bus verb operators
28 *
29 * Returns 0 if successful, or a negative error code.
30 */
31int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
32 const struct hdac_bus_ops *ops)
33{
34 memset(bus, 0, sizeof(*bus));
35 bus->dev = dev;
36 if (ops)
37 bus->ops = ops;
38 else
39 bus->ops = &default_ops;
40 bus->dma_type = SNDRV_DMA_TYPE_DEV;
41 INIT_LIST_HEAD(list: &bus->stream_list);
42 INIT_LIST_HEAD(list: &bus->codec_list);
43 INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events);
44 spin_lock_init(&bus->reg_lock);
45 mutex_init(&bus->cmd_mutex);
46 mutex_init(&bus->lock);
47 INIT_LIST_HEAD(list: &bus->hlink_list);
48 init_waitqueue_head(&bus->rirb_wq);
49 bus->irq = -1;
50
51 /*
52 * Default value of '8' is as per the HD audio specification (Rev 1.0a).
53 * Following relation is used to derive STRIPE control value.
54 * For sample rate <= 48K:
55 * { ((num_channels * bits_per_sample) / number of SDOs) >= 8 }
56 * For sample rate > 48K:
57 * { ((num_channels * bits_per_sample * rate/48000) /
58 * number of SDOs) >= 8 }
59 */
60 bus->sdo_limit = 8;
61
62 return 0;
63}
64EXPORT_SYMBOL_GPL(snd_hdac_bus_init);
65
66/**
67 * snd_hdac_bus_exit - clean up a HD-audio bas bus
68 * @bus: the pointer to bus object
69 */
70void snd_hdac_bus_exit(struct hdac_bus *bus)
71{
72 WARN_ON(!list_empty(&bus->stream_list));
73 WARN_ON(!list_empty(&bus->codec_list));
74 cancel_work_sync(work: &bus->unsol_work);
75}
76EXPORT_SYMBOL_GPL(snd_hdac_bus_exit);
77
78/**
79 * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus
80 * @bus: bus object
81 * @addr: the HDAC device address
82 * @cmd: HD-audio encoded verb
83 * @res: pointer to store the response, NULL if performing asynchronously
84 *
85 * Returns 0 if successful, or a negative error code.
86 */
87int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr,
88 unsigned int cmd, unsigned int *res)
89{
90 int err;
91
92 mutex_lock(&bus->cmd_mutex);
93 err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res);
94 mutex_unlock(lock: &bus->cmd_mutex);
95 return err;
96}
97
98/**
99 * snd_hdac_bus_exec_verb_unlocked - unlocked version
100 * @bus: bus object
101 * @addr: the HDAC device address
102 * @cmd: HD-audio encoded verb
103 * @res: pointer to store the response, NULL if performing asynchronously
104 *
105 * Returns 0 if successful, or a negative error code.
106 */
107int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr,
108 unsigned int cmd, unsigned int *res)
109{
110 unsigned int tmp;
111 int err;
112
113 if (cmd == ~0)
114 return -EINVAL;
115
116 if (res)
117 *res = -1;
118 else if (bus->sync_write)
119 res = &tmp;
120 for (;;) {
121 trace_hda_send_cmd(bus, cmd);
122 err = bus->ops->command(bus, cmd);
123 if (err != -EAGAIN)
124 break;
125 /* process pending verbs */
126 err = bus->ops->get_response(bus, addr, &tmp);
127 if (err)
128 break;
129 }
130 if (!err && res) {
131 err = bus->ops->get_response(bus, addr, res);
132 trace_hda_get_response(bus, addr, res: *res);
133 }
134 return err;
135}
136EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked);
137
138/**
139 * snd_hdac_bus_queue_event - add an unsolicited event to queue
140 * @bus: the BUS
141 * @res: unsolicited event (lower 32bit of RIRB entry)
142 * @res_ex: codec addr and flags (upper 32bit or RIRB entry)
143 *
144 * Adds the given event to the queue. The events are processed in
145 * the workqueue asynchronously. Call this function in the interrupt
146 * hanlder when RIRB receives an unsolicited event.
147 */
148void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex)
149{
150 unsigned int wp;
151
152 if (!bus)
153 return;
154
155 trace_hda_unsol_event(bus, res, res_ex);
156 wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE;
157 bus->unsol_wp = wp;
158
159 wp <<= 1;
160 bus->unsol_queue[wp] = res;
161 bus->unsol_queue[wp + 1] = res_ex;
162
163 schedule_work(work: &bus->unsol_work);
164}
165
166/*
167 * process queued unsolicited events
168 */
169static void snd_hdac_bus_process_unsol_events(struct work_struct *work)
170{
171 struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work);
172 struct hdac_device *codec;
173 struct hdac_driver *drv;
174 unsigned int rp, caddr, res;
175
176 spin_lock_irq(lock: &bus->reg_lock);
177 while (bus->unsol_rp != bus->unsol_wp) {
178 rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE;
179 bus->unsol_rp = rp;
180 rp <<= 1;
181 res = bus->unsol_queue[rp];
182 caddr = bus->unsol_queue[rp + 1];
183 if (!(caddr & (1 << 4))) /* no unsolicited event? */
184 continue;
185 codec = bus->caddr_tbl[caddr & 0x0f];
186 if (!codec || !codec->registered)
187 continue;
188 spin_unlock_irq(lock: &bus->reg_lock);
189 drv = drv_to_hdac_driver(codec->dev.driver);
190 if (drv->unsol_event)
191 drv->unsol_event(codec, res);
192 spin_lock_irq(lock: &bus->reg_lock);
193 }
194 spin_unlock_irq(lock: &bus->reg_lock);
195}
196
197/**
198 * snd_hdac_bus_add_device - Add a codec to bus
199 * @bus: HDA core bus
200 * @codec: HDA core device to add
201 *
202 * Adds the given codec to the list in the bus. The caddr_tbl array
203 * and codec_powered bits are updated, as well.
204 * Returns zero if success, or a negative error code.
205 */
206int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec)
207{
208 if (bus->caddr_tbl[codec->addr]) {
209 dev_err(bus->dev, "address 0x%x is already occupied\n",
210 codec->addr);
211 return -EBUSY;
212 }
213
214 list_add_tail(new: &codec->list, head: &bus->codec_list);
215 bus->caddr_tbl[codec->addr] = codec;
216 set_bit(nr: codec->addr, addr: &bus->codec_powered);
217 bus->num_codecs++;
218 return 0;
219}
220
221/**
222 * snd_hdac_bus_remove_device - Remove a codec from bus
223 * @bus: HDA core bus
224 * @codec: HDA core device to remove
225 */
226void snd_hdac_bus_remove_device(struct hdac_bus *bus,
227 struct hdac_device *codec)
228{
229 WARN_ON(bus != codec->bus);
230 if (list_empty(head: &codec->list))
231 return;
232 list_del_init(entry: &codec->list);
233 bus->caddr_tbl[codec->addr] = NULL;
234 clear_bit(nr: codec->addr, addr: &bus->codec_powered);
235 bus->num_codecs--;
236 flush_work(work: &bus->unsol_work);
237}
238
239#ifdef CONFIG_SND_HDA_ALIGNED_MMIO
240/* Helpers for aligned read/write of mmio space, for Tegra */
241unsigned int snd_hdac_aligned_read(void __iomem *addr, unsigned int mask)
242{
243 void __iomem *aligned_addr =
244 (void __iomem *)((unsigned long)(addr) & ~0x3);
245 unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
246 unsigned int v;
247
248 v = readl(aligned_addr);
249 return (v >> shift) & mask;
250}
251EXPORT_SYMBOL_GPL(snd_hdac_aligned_read);
252
253void snd_hdac_aligned_write(unsigned int val, void __iomem *addr,
254 unsigned int mask)
255{
256 void __iomem *aligned_addr =
257 (void __iomem *)((unsigned long)(addr) & ~0x3);
258 unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
259 unsigned int v;
260
261 v = readl(aligned_addr);
262 v &= ~(mask << shift);
263 v |= val << shift;
264 writel(v, aligned_addr);
265}
266EXPORT_SYMBOL_GPL(snd_hdac_aligned_write);
267#endif /* CONFIG_SND_HDA_ALIGNED_MMIO */
268
269void snd_hdac_codec_link_up(struct hdac_device *codec)
270{
271 struct hdac_bus *bus = codec->bus;
272
273 if (bus->ops->link_power)
274 bus->ops->link_power(codec, true);
275 else
276 snd_hdac_bus_link_power(hdev: codec, enable: true);
277}
278EXPORT_SYMBOL_GPL(snd_hdac_codec_link_up);
279
280void snd_hdac_codec_link_down(struct hdac_device *codec)
281{
282 struct hdac_bus *bus = codec->bus;
283
284 if (bus->ops->link_power)
285 bus->ops->link_power(codec, false);
286 else
287 snd_hdac_bus_link_power(hdev: codec, enable: false);
288}
289EXPORT_SYMBOL_GPL(snd_hdac_codec_link_down);
290

source code of linux/sound/hda/hdac_bus.c