xref: /openbmc/linux/sound/soc/sh/hac.c (revision 4f6cce39) 
1 /*
2  * Hitachi Audio Controller (AC97) support for SH7760/SH7780
3  *
4  * Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net>
5  *  licensed under the terms outlined in the file COPYING at the root
6  *  of the linux kernel sources.
7  *
8  * dont forget to set IPSEL/OMSEL register bits (in your board code) to
9  * enable HAC output pins!
10  */
11 
12 /* BIG FAT FIXME: although the SH7760 has 2 independent AC97 units, only
13  * the FIRST can be used since ASoC does not pass any information to the
14  * ac97_read/write() functions regarding WHICH unit to use.  You'll have
15  * to edit the code a bit to use the other AC97 unit.		--mlau
16  */
17 
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/interrupt.h>
22 #include <linux/wait.h>
23 #include <linux/delay.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/ac97_codec.h>
27 #include <sound/initval.h>
28 #include <sound/soc.h>
29 
30 /* regs and bits */
31 #define HACCR		0x08
32 #define HACCSAR		0x20
33 #define HACCSDR		0x24
34 #define HACPCML		0x28
35 #define HACPCMR		0x2C
36 #define HACTIER		0x50
37 #define	HACTSR		0x54
38 #define HACRIER		0x58
39 #define HACRSR		0x5C
40 #define HACACR		0x60
41 
42 #define CR_CR		(1 << 15)	/* "codec-ready" indicator */
43 #define CR_CDRT		(1 << 11)	/* cold reset */
44 #define CR_WMRT		(1 << 10)	/* warm reset */
45 #define CR_B9		(1 << 9)	/* the mysterious "bit 9" */
46 #define CR_ST		(1 << 5)	/* AC97 link start bit */
47 
48 #define CSAR_RD		(1 << 19)	/* AC97 data read bit */
49 #define CSAR_WR		(0)
50 
51 #define TSR_CMDAMT	(1 << 31)
52 #define TSR_CMDDMT	(1 << 30)
53 
54 #define RSR_STARY	(1 << 22)
55 #define RSR_STDRY	(1 << 21)
56 
57 #define ACR_DMARX16	(1 << 30)
58 #define ACR_DMATX16	(1 << 29)
59 #define ACR_TX12ATOM	(1 << 26)
60 #define ACR_DMARX20	((1 << 24) | (1 << 22))
61 #define ACR_DMATX20	((1 << 23) | (1 << 21))
62 
63 #define CSDR_SHIFT	4
64 #define CSDR_MASK	(0xffff << CSDR_SHIFT)
65 #define CSAR_SHIFT	12
66 #define CSAR_MASK	(0x7f << CSAR_SHIFT)
67 
68 #define AC97_WRITE_RETRY	1
69 #define AC97_READ_RETRY		5
70 
71 /* manual-suggested AC97 codec access timeouts (us) */
72 #define TMO_E1	500	/* 21 < E1 < 1000 */
73 #define TMO_E2	13	/* 13 < E2 */
74 #define TMO_E3	21	/* 21 < E3 */
75 #define TMO_E4	500	/* 21 < E4 < 1000 */
76 
77 struct hac_priv {
78 	unsigned long mmio;	/* HAC base address */
79 } hac_cpu_data[] = {
80 #if defined(CONFIG_CPU_SUBTYPE_SH7760)
81 	{
82 		.mmio	= 0xFE240000,
83 	},
84 	{
85 		.mmio	= 0xFE250000,
86 	},
87 #elif defined(CONFIG_CPU_SUBTYPE_SH7780)
88 	{
89 		.mmio	= 0xFFE40000,
90 	},
91 #else
92 #error "Unsupported SuperH SoC"
93 #endif
94 };
95 
96 #define HACREG(reg)	(*(unsigned long *)(hac->mmio + (reg)))
97 
98 /*
99  * AC97 read/write flow as outlined in the SH7760 manual (pages 903-906)
100  */
101 static int hac_get_codec_data(struct hac_priv *hac, unsigned short r,
102 			      unsigned short *v)
103 {
104 	unsigned int to1, to2, i;
105 	unsigned short adr;
106 
107 	for (i = AC97_READ_RETRY; i; i--) {
108 		*v = 0;
109 		/* wait for HAC to receive something from the codec */
110 		for (to1 = TMO_E4;
111 		     to1 && !(HACREG(HACRSR) & RSR_STARY);
112 		     --to1)
113 			udelay(1);
114 		for (to2 = TMO_E4;
115 		     to2 && !(HACREG(HACRSR) & RSR_STDRY);
116 		     --to2)
117 			udelay(1);
118 
119 		if (!to1 && !to2)
120 			return 0;	/* codec comm is down */
121 
122 		adr = ((HACREG(HACCSAR) & CSAR_MASK) >> CSAR_SHIFT);
123 		*v  = ((HACREG(HACCSDR) & CSDR_MASK) >> CSDR_SHIFT);
124 
125 		HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
126 
127 		if (r == adr)
128 			break;
129 
130 		/* manual says: wait at least 21 usec before retrying */
131 		udelay(21);
132 	}
133 	HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
134 	return i;
135 }
136 
137 static unsigned short hac_read_codec_aux(struct hac_priv *hac,
138 					 unsigned short reg)
139 {
140 	unsigned short val;
141 	unsigned int i, to;
142 
143 	for (i = AC97_READ_RETRY; i; i--) {
144 		/* send_read_request */
145 		local_irq_disable();
146 		HACREG(HACTSR) &= ~(TSR_CMDAMT);
147 		HACREG(HACCSAR) = (reg << CSAR_SHIFT) | CSAR_RD;
148 		local_irq_enable();
149 
150 		for (to = TMO_E3;
151 		     to && !(HACREG(HACTSR) & TSR_CMDAMT);
152 		     --to)
153 			udelay(1);
154 
155 		HACREG(HACTSR) &= ~TSR_CMDAMT;
156 		val = 0;
157 		if (hac_get_codec_data(hac, reg, &val) != 0)
158 			break;
159 	}
160 
161 	return i ? val : ~0;
162 }
163 
164 static void hac_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
165 			   unsigned short val)
166 {
167 	int unit_id = 0 /* ac97->private_data */;
168 	struct hac_priv *hac = &hac_cpu_data[unit_id];
169 	unsigned int i, to;
170 	/* write_codec_aux */
171 	for (i = AC97_WRITE_RETRY; i; i--) {
172 		/* send_write_request */
173 		local_irq_disable();
174 		HACREG(HACTSR) &= ~(TSR_CMDDMT | TSR_CMDAMT);
175 		HACREG(HACCSDR) = (val << CSDR_SHIFT);
176 		HACREG(HACCSAR) = (reg << CSAR_SHIFT) & (~CSAR_RD);
177 		local_irq_enable();
178 
179 		/* poll-wait for CMDAMT and CMDDMT */
180 		for (to = TMO_E1;
181 		     to && !(HACREG(HACTSR) & (TSR_CMDAMT|TSR_CMDDMT));
182 		     --to)
183 			udelay(1);
184 
185 		HACREG(HACTSR) &= ~(TSR_CMDAMT | TSR_CMDDMT);
186 		if (to)
187 			break;
188 		/* timeout, try again */
189 	}
190 }
191 
192 static unsigned short hac_ac97_read(struct snd_ac97 *ac97,
193 				    unsigned short reg)
194 {
195 	int unit_id = 0 /* ac97->private_data */;
196 	struct hac_priv *hac = &hac_cpu_data[unit_id];
197 	return hac_read_codec_aux(hac, reg);
198 }
199 
200 static void hac_ac97_warmrst(struct snd_ac97 *ac97)
201 {
202 	int unit_id = 0 /* ac97->private_data */;
203 	struct hac_priv *hac = &hac_cpu_data[unit_id];
204 	unsigned int tmo;
205 
206 	HACREG(HACCR) = CR_WMRT | CR_ST | CR_B9;
207 	msleep(10);
208 	HACREG(HACCR) = CR_ST | CR_B9;
209 	for (tmo = 1000; (tmo > 0) && !(HACREG(HACCR) & CR_CR); tmo--)
210 		udelay(1);
211 
212 	if (!tmo)
213 		printk(KERN_INFO "hac: reset: AC97 link down!\n");
214 	/* settings this bit lets us have a conversation with codec */
215 	HACREG(HACACR) |= ACR_TX12ATOM;
216 }
217 
218 static void hac_ac97_coldrst(struct snd_ac97 *ac97)
219 {
220 	int unit_id = 0 /* ac97->private_data */;
221 	struct hac_priv *hac;
222 	hac = &hac_cpu_data[unit_id];
223 
224 	HACREG(HACCR) = 0;
225 	HACREG(HACCR) = CR_CDRT | CR_ST | CR_B9;
226 	msleep(10);
227 	hac_ac97_warmrst(ac97);
228 }
229 
230 static struct snd_ac97_bus_ops hac_ac97_ops = {
231 	.read	= hac_ac97_read,
232 	.write	= hac_ac97_write,
233 	.reset	= hac_ac97_coldrst,
234 	.warm_reset = hac_ac97_warmrst,
235 };
236 
237 static int hac_hw_params(struct snd_pcm_substream *substream,
238 			 struct snd_pcm_hw_params *params,
239 			 struct snd_soc_dai *dai)
240 {
241 	struct hac_priv *hac = &hac_cpu_data[dai->id];
242 	int d = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1;
243 
244 	switch (params->msbits) {
245 	case 16:
246 		HACREG(HACACR) |= d ?  ACR_DMARX16 :  ACR_DMATX16;
247 		HACREG(HACACR) &= d ? ~ACR_DMARX20 : ~ACR_DMATX20;
248 		break;
249 	case 20:
250 		HACREG(HACACR) &= d ? ~ACR_DMARX16 : ~ACR_DMATX16;
251 		HACREG(HACACR) |= d ?  ACR_DMARX20 :  ACR_DMATX20;
252 		break;
253 	default:
254 		pr_debug("hac: invalid depth %d bit\n", params->msbits);
255 		return -EINVAL;
256 		break;
257 	}
258 
259 	return 0;
260 }
261 
262 #define AC97_RATES	\
263 	SNDRV_PCM_RATE_8000_192000
264 
265 #define AC97_FMTS	\
266 	SNDRV_PCM_FMTBIT_S16_LE
267 
268 static const struct snd_soc_dai_ops hac_dai_ops = {
269 	.hw_params	= hac_hw_params,
270 };
271 
272 static struct snd_soc_dai_driver sh4_hac_dai[] = {
273 {
274 	.name			= "hac-dai.0",
275 	.bus_control		= true,
276 	.playback = {
277 		.rates		= AC97_RATES,
278 		.formats	= AC97_FMTS,
279 		.channels_min	= 2,
280 		.channels_max	= 2,
281 	},
282 	.capture = {
283 		.rates		= AC97_RATES,
284 		.formats	= AC97_FMTS,
285 		.channels_min	= 2,
286 		.channels_max	= 2,
287 	},
288 	.ops = &hac_dai_ops,
289 },
290 #ifdef CONFIG_CPU_SUBTYPE_SH7760
291 {
292 	.name			= "hac-dai.1",
293 	.id			= 1,
294 	.playback = {
295 		.rates		= AC97_RATES,
296 		.formats	= AC97_FMTS,
297 		.channels_min	= 2,
298 		.channels_max	= 2,
299 	},
300 	.capture = {
301 		.rates		= AC97_RATES,
302 		.formats	= AC97_FMTS,
303 		.channels_min	= 2,
304 		.channels_max	= 2,
305 	},
306 	.ops = &hac_dai_ops,
307 
308 },
309 #endif
310 };
311 
312 static const struct snd_soc_component_driver sh4_hac_component = {
313 	.name		= "sh4-hac",
314 };
315 
316 static int hac_soc_platform_probe(struct platform_device *pdev)
317 {
318 	ret = snd_soc_set_ac97_ops(&hac_ac97_ops);
319 	if (ret != 0)
320 		return ret;
321 
322 	return snd_soc_register_component(&pdev->dev, &sh4_hac_component,
323 					  sh4_hac_dai, ARRAY_SIZE(sh4_hac_dai));
324 }
325 
326 static int hac_soc_platform_remove(struct platform_device *pdev)
327 {
328 	snd_soc_unregister_component(&pdev->dev);
329 	snd_soc_set_ac97_ops(NULL);
330 	return 0;
331 }
332 
333 static struct platform_driver hac_pcm_driver = {
334 	.driver = {
335 			.name = "hac-pcm-audio",
336 	},
337 
338 	.probe = hac_soc_platform_probe,
339 	.remove = hac_soc_platform_remove,
340 };
341 
342 module_platform_driver(hac_pcm_driver);
343 
344 MODULE_LICENSE("GPL");
345 MODULE_DESCRIPTION("SuperH onchip HAC (AC97) audio driver");
346 MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");
347