1/*
2 * soc-ac97.c  --  ALSA SoC Audio Layer AC97 support
3 *
4 * Copyright 2005 Wolfson Microelectronics PLC.
5 * Copyright 2005 Openedhand Ltd.
6 * Copyright (C) 2010 Slimlogic Ltd.
7 * Copyright (C) 2010 Texas Instruments Inc.
8 *
9 * Author: Liam Girdwood <lrg@slimlogic.co.uk>
10 *         with code, comments and ideas from :-
11 *         Richard Purdie <richard@openedhand.com>
12 *
13 *  This program is free software; you can redistribute  it and/or modify it
14 *  under  the terms of  the GNU General  Public License as published by the
15 *  Free Software Foundation;  either version 2 of the  License, or (at your
16 *  option) any later version.
17 */
18
19#include <linux/ctype.h>
20#include <linux/delay.h>
21#include <linux/export.h>
22#include <linux/gpio.h>
23#include <linux/init.h>
24#include <linux/of_gpio.h>
25#include <linux/of.h>
26#include <linux/pinctrl/consumer.h>
27#include <linux/slab.h>
28#include <sound/ac97_codec.h>
29#include <sound/soc.h>
30
31struct snd_ac97_reset_cfg {
32	struct pinctrl *pctl;
33	struct pinctrl_state *pstate_reset;
34	struct pinctrl_state *pstate_warm_reset;
35	struct pinctrl_state *pstate_run;
36	int gpio_sdata;
37	int gpio_sync;
38	int gpio_reset;
39};
40
41static struct snd_ac97_bus soc_ac97_bus = {
42	.ops = NULL, /* Gets initialized in snd_soc_set_ac97_ops() */
43};
44
45static void soc_ac97_device_release(struct device *dev)
46{
47	kfree(to_ac97_t(dev));
48}
49
50/**
51 * snd_soc_alloc_ac97_codec() - Allocate new a AC'97 device
52 * @codec: The CODEC for which to create the AC'97 device
53 *
54 * Allocated a new snd_ac97 device and intializes it, but does not yet register
55 * it. The caller is responsible to either call device_add(&ac97->dev) to
56 * register the device, or to call put_device(&ac97->dev) to free the device.
57 *
58 * Returns: A snd_ac97 device or a PTR_ERR in case of an error.
59 */
60struct snd_ac97 *snd_soc_alloc_ac97_codec(struct snd_soc_codec *codec)
61{
62	struct snd_ac97 *ac97;
63
64	ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
65	if (ac97 == NULL)
66		return ERR_PTR(-ENOMEM);
67
68	ac97->bus = &soc_ac97_bus;
69	ac97->num = 0;
70
71	ac97->dev.bus = &ac97_bus_type;
72	ac97->dev.parent = codec->component.card->dev;
73	ac97->dev.release = soc_ac97_device_release;
74
75	dev_set_name(&ac97->dev, "%d-%d:%s",
76		     codec->component.card->snd_card->number, 0,
77		     codec->component.name);
78
79	device_initialize(&ac97->dev);
80
81	return ac97;
82}
83EXPORT_SYMBOL(snd_soc_alloc_ac97_codec);
84
85/**
86 * snd_soc_new_ac97_codec - initailise AC97 device
87 * @codec: audio codec
88 *
89 * Initialises AC97 codec resources for use by ad-hoc devices only.
90 */
91struct snd_ac97 *snd_soc_new_ac97_codec(struct snd_soc_codec *codec)
92{
93	struct snd_ac97 *ac97;
94	int ret;
95
96	ac97 = snd_soc_alloc_ac97_codec(codec);
97	if (IS_ERR(ac97))
98		return ac97;
99
100	ret = device_add(&ac97->dev);
101	if (ret) {
102		put_device(&ac97->dev);
103		return ERR_PTR(ret);
104	}
105
106	return ac97;
107}
108EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
109
110/**
111 * snd_soc_free_ac97_codec - free AC97 codec device
112 * @codec: audio codec
113 *
114 * Frees AC97 codec device resources.
115 */
116void snd_soc_free_ac97_codec(struct snd_ac97 *ac97)
117{
118	device_del(&ac97->dev);
119	ac97->bus = NULL;
120	put_device(&ac97->dev);
121}
122EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);
123
124static struct snd_ac97_reset_cfg snd_ac97_rst_cfg;
125
126static void snd_soc_ac97_warm_reset(struct snd_ac97 *ac97)
127{
128	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
129
130	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_warm_reset);
131
132	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 1);
133
134	udelay(10);
135
136	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
137
138	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
139	msleep(2);
140}
141
142static void snd_soc_ac97_reset(struct snd_ac97 *ac97)
143{
144	struct pinctrl *pctl = snd_ac97_rst_cfg.pctl;
145
146	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_reset);
147
148	gpio_direction_output(snd_ac97_rst_cfg.gpio_sync, 0);
149	gpio_direction_output(snd_ac97_rst_cfg.gpio_sdata, 0);
150	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 0);
151
152	udelay(10);
153
154	gpio_direction_output(snd_ac97_rst_cfg.gpio_reset, 1);
155
156	pinctrl_select_state(pctl, snd_ac97_rst_cfg.pstate_run);
157	msleep(2);
158}
159
160static int snd_soc_ac97_parse_pinctl(struct device *dev,
161		struct snd_ac97_reset_cfg *cfg)
162{
163	struct pinctrl *p;
164	struct pinctrl_state *state;
165	int gpio;
166	int ret;
167
168	p = devm_pinctrl_get(dev);
169	if (IS_ERR(p)) {
170		dev_err(dev, "Failed to get pinctrl\n");
171		return PTR_ERR(p);
172	}
173	cfg->pctl = p;
174
175	state = pinctrl_lookup_state(p, "ac97-reset");
176	if (IS_ERR(state)) {
177		dev_err(dev, "Can't find pinctrl state ac97-reset\n");
178		return PTR_ERR(state);
179	}
180	cfg->pstate_reset = state;
181
182	state = pinctrl_lookup_state(p, "ac97-warm-reset");
183	if (IS_ERR(state)) {
184		dev_err(dev, "Can't find pinctrl state ac97-warm-reset\n");
185		return PTR_ERR(state);
186	}
187	cfg->pstate_warm_reset = state;
188
189	state = pinctrl_lookup_state(p, "ac97-running");
190	if (IS_ERR(state)) {
191		dev_err(dev, "Can't find pinctrl state ac97-running\n");
192		return PTR_ERR(state);
193	}
194	cfg->pstate_run = state;
195
196	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 0);
197	if (gpio < 0) {
198		dev_err(dev, "Can't find ac97-sync gpio\n");
199		return gpio;
200	}
201	ret = devm_gpio_request(dev, gpio, "AC97 link sync");
202	if (ret) {
203		dev_err(dev, "Failed requesting ac97-sync gpio\n");
204		return ret;
205	}
206	cfg->gpio_sync = gpio;
207
208	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 1);
209	if (gpio < 0) {
210		dev_err(dev, "Can't find ac97-sdata gpio %d\n", gpio);
211		return gpio;
212	}
213	ret = devm_gpio_request(dev, gpio, "AC97 link sdata");
214	if (ret) {
215		dev_err(dev, "Failed requesting ac97-sdata gpio\n");
216		return ret;
217	}
218	cfg->gpio_sdata = gpio;
219
220	gpio = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
221	if (gpio < 0) {
222		dev_err(dev, "Can't find ac97-reset gpio\n");
223		return gpio;
224	}
225	ret = devm_gpio_request(dev, gpio, "AC97 link reset");
226	if (ret) {
227		dev_err(dev, "Failed requesting ac97-reset gpio\n");
228		return ret;
229	}
230	cfg->gpio_reset = gpio;
231
232	return 0;
233}
234
235struct snd_ac97_bus_ops *soc_ac97_ops;
236EXPORT_SYMBOL_GPL(soc_ac97_ops);
237
238int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops)
239{
240	if (ops == soc_ac97_ops)
241		return 0;
242
243	if (soc_ac97_ops && ops)
244		return -EBUSY;
245
246	soc_ac97_ops = ops;
247	soc_ac97_bus.ops = ops;
248
249	return 0;
250}
251EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops);
252
253/**
254 * snd_soc_set_ac97_ops_of_reset - Set ac97 ops with generic ac97 reset functions
255 *
256 * This function sets the reset and warm_reset properties of ops and parses
257 * the device node of pdev to get pinctrl states and gpio numbers to use.
258 */
259int snd_soc_set_ac97_ops_of_reset(struct snd_ac97_bus_ops *ops,
260		struct platform_device *pdev)
261{
262	struct device *dev = &pdev->dev;
263	struct snd_ac97_reset_cfg cfg;
264	int ret;
265
266	ret = snd_soc_ac97_parse_pinctl(dev, &cfg);
267	if (ret)
268		return ret;
269
270	ret = snd_soc_set_ac97_ops(ops);
271	if (ret)
272		return ret;
273
274	ops->warm_reset = snd_soc_ac97_warm_reset;
275	ops->reset = snd_soc_ac97_reset;
276
277	snd_ac97_rst_cfg = cfg;
278	return 0;
279}
280EXPORT_SYMBOL_GPL(snd_soc_set_ac97_ops_of_reset);
281