xref: /openbmc/linux/sound/hda/hdac_bus.c (revision 3ce311af)
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 
15 static void snd_hdac_bus_process_unsol_events(struct work_struct *work);
16 
17 static const struct hdac_bus_ops default_ops = {
18 	.command = snd_hdac_bus_send_cmd,
19 	.get_response = snd_hdac_bus_get_response,
20 };
21 
22 /**
23  * snd_hdac_bus_init - initialize a HD-audio bas bus
24  * @bus: the pointer to bus object
25  * @ops: bus verb operators
26  *
27  * Returns 0 if successful, or a negative error code.
28  */
29 int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
30 		      const struct hdac_bus_ops *ops)
31 {
32 	memset(bus, 0, sizeof(*bus));
33 	bus->dev = dev;
34 	if (ops)
35 		bus->ops = ops;
36 	else
37 		bus->ops = &default_ops;
38 	bus->dma_type = SNDRV_DMA_TYPE_DEV;
39 	INIT_LIST_HEAD(&bus->stream_list);
40 	INIT_LIST_HEAD(&bus->codec_list);
41 	INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events);
42 	spin_lock_init(&bus->reg_lock);
43 	mutex_init(&bus->cmd_mutex);
44 	mutex_init(&bus->lock);
45 	INIT_LIST_HEAD(&bus->hlink_list);
46 	bus->irq = -1;
47 	return 0;
48 }
49 EXPORT_SYMBOL_GPL(snd_hdac_bus_init);
50 
51 /**
52  * snd_hdac_bus_exit - clean up a HD-audio bas bus
53  * @bus: the pointer to bus object
54  */
55 void snd_hdac_bus_exit(struct hdac_bus *bus)
56 {
57 	WARN_ON(!list_empty(&bus->stream_list));
58 	WARN_ON(!list_empty(&bus->codec_list));
59 	cancel_work_sync(&bus->unsol_work);
60 }
61 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit);
62 
63 /**
64  * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus
65  * @bus: bus object
66  * @cmd: HD-audio encoded verb
67  * @res: pointer to store the response, NULL if performing asynchronously
68  *
69  * Returns 0 if successful, or a negative error code.
70  */
71 int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr,
72 			   unsigned int cmd, unsigned int *res)
73 {
74 	int err;
75 
76 	mutex_lock(&bus->cmd_mutex);
77 	err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res);
78 	mutex_unlock(&bus->cmd_mutex);
79 	return err;
80 }
81 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb);
82 
83 /**
84  * snd_hdac_bus_exec_verb_unlocked - unlocked version
85  * @bus: bus object
86  * @cmd: HD-audio encoded verb
87  * @res: pointer to store the response, NULL if performing asynchronously
88  *
89  * Returns 0 if successful, or a negative error code.
90  */
91 int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr,
92 				    unsigned int cmd, unsigned int *res)
93 {
94 	unsigned int tmp;
95 	int err;
96 
97 	if (cmd == ~0)
98 		return -EINVAL;
99 
100 	if (res)
101 		*res = -1;
102 	else if (bus->sync_write)
103 		res = &tmp;
104 	for (;;) {
105 		trace_hda_send_cmd(bus, cmd);
106 		err = bus->ops->command(bus, cmd);
107 		if (err != -EAGAIN)
108 			break;
109 		/* process pending verbs */
110 		err = bus->ops->get_response(bus, addr, &tmp);
111 		if (err)
112 			break;
113 	}
114 	if (!err && res) {
115 		err = bus->ops->get_response(bus, addr, res);
116 		trace_hda_get_response(bus, addr, *res);
117 	}
118 	return err;
119 }
120 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked);
121 
122 /**
123  * snd_hdac_bus_queue_event - add an unsolicited event to queue
124  * @bus: the BUS
125  * @res: unsolicited event (lower 32bit of RIRB entry)
126  * @res_ex: codec addr and flags (upper 32bit or RIRB entry)
127  *
128  * Adds the given event to the queue.  The events are processed in
129  * the workqueue asynchronously.  Call this function in the interrupt
130  * hanlder when RIRB receives an unsolicited event.
131  */
132 void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex)
133 {
134 	unsigned int wp;
135 
136 	if (!bus)
137 		return;
138 
139 	trace_hda_unsol_event(bus, res, res_ex);
140 	wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE;
141 	bus->unsol_wp = wp;
142 
143 	wp <<= 1;
144 	bus->unsol_queue[wp] = res;
145 	bus->unsol_queue[wp + 1] = res_ex;
146 
147 	schedule_work(&bus->unsol_work);
148 }
149 EXPORT_SYMBOL_GPL(snd_hdac_bus_queue_event);
150 
151 /*
152  * process queued unsolicited events
153  */
154 static void snd_hdac_bus_process_unsol_events(struct work_struct *work)
155 {
156 	struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work);
157 	struct hdac_device *codec;
158 	struct hdac_driver *drv;
159 	unsigned int rp, caddr, res;
160 
161 	while (bus->unsol_rp != bus->unsol_wp) {
162 		rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE;
163 		bus->unsol_rp = rp;
164 		rp <<= 1;
165 		res = bus->unsol_queue[rp];
166 		caddr = bus->unsol_queue[rp + 1];
167 		if (!(caddr & (1 << 4))) /* no unsolicited event? */
168 			continue;
169 		codec = bus->caddr_tbl[caddr & 0x0f];
170 		if (!codec || !codec->dev.driver)
171 			continue;
172 		drv = drv_to_hdac_driver(codec->dev.driver);
173 		if (drv->unsol_event)
174 			drv->unsol_event(codec, res);
175 	}
176 }
177 
178 /**
179  * snd_hdac_bus_add_device - Add a codec to bus
180  * @bus: HDA core bus
181  * @codec: HDA core device to add
182  *
183  * Adds the given codec to the list in the bus.  The caddr_tbl array
184  * and codec_powered bits are updated, as well.
185  * Returns zero if success, or a negative error code.
186  */
187 int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec)
188 {
189 	if (bus->caddr_tbl[codec->addr]) {
190 		dev_err(bus->dev, "address 0x%x is already occupied\n",
191 			codec->addr);
192 		return -EBUSY;
193 	}
194 
195 	list_add_tail(&codec->list, &bus->codec_list);
196 	bus->caddr_tbl[codec->addr] = codec;
197 	set_bit(codec->addr, &bus->codec_powered);
198 	bus->num_codecs++;
199 	return 0;
200 }
201 
202 /**
203  * snd_hdac_bus_remove_device - Remove a codec from bus
204  * @bus: HDA core bus
205  * @codec: HDA core device to remove
206  */
207 void snd_hdac_bus_remove_device(struct hdac_bus *bus,
208 				struct hdac_device *codec)
209 {
210 	WARN_ON(bus != codec->bus);
211 	if (list_empty(&codec->list))
212 		return;
213 	list_del_init(&codec->list);
214 	bus->caddr_tbl[codec->addr] = NULL;
215 	clear_bit(codec->addr, &bus->codec_powered);
216 	bus->num_codecs--;
217 	flush_work(&bus->unsol_work);
218 }
219 
220 #ifdef CONFIG_SND_HDA_ALIGNED_MMIO
221 /* Helpers for aligned read/write of mmio space, for Tegra */
222 unsigned int snd_hdac_aligned_read(void __iomem *addr, unsigned int mask)
223 {
224 	void __iomem *aligned_addr =
225 		(void __iomem *)((unsigned long)(addr) & ~0x3);
226 	unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
227 	unsigned int v;
228 
229 	v = readl(aligned_addr);
230 	return (v >> shift) & mask;
231 }
232 EXPORT_SYMBOL_GPL(snd_hdac_aligned_read);
233 
234 void snd_hdac_aligned_write(unsigned int val, void __iomem *addr,
235 			    unsigned int mask)
236 {
237 	void __iomem *aligned_addr =
238 		(void __iomem *)((unsigned long)(addr) & ~0x3);
239 	unsigned int shift = ((unsigned long)(addr) & 0x3) << 3;
240 	unsigned int v;
241 
242 	v = readl(aligned_addr);
243 	v &= ~(mask << shift);
244 	v |= val << shift;
245 	writel(v, aligned_addr);
246 }
247 EXPORT_SYMBOL_GPL(snd_hdac_aligned_write);
248 #endif /* CONFIG_SND_HDA_ALIGNED_MMIO */
249