xref: /openbmc/linux/sound/soc/sh/hac.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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/driver.h>
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/ac97_codec.h>
28 #include <sound/initval.h>
29 #include <sound/soc.h>
30 
31 /* regs and bits */
32 #define HACCR		0x08
33 #define HACCSAR		0x20
34 #define HACCSDR		0x24
35 #define HACPCML		0x28
36 #define HACPCMR		0x2C
37 #define HACTIER		0x50
38 #define	HACTSR		0x54
39 #define HACRIER		0x58
40 #define HACRSR		0x5C
41 #define HACACR		0x60
42 
43 #define CR_CR		(1 << 15)	/* "codec-ready" indicator */
44 #define CR_CDRT		(1 << 11)	/* cold reset */
45 #define CR_WMRT		(1 << 10)	/* warm reset */
46 #define CR_B9		(1 << 9)	/* the mysterious "bit 9" */
47 #define CR_ST		(1 << 5)	/* AC97 link start bit */
48 
49 #define CSAR_RD		(1 << 19)	/* AC97 data read bit */
50 #define CSAR_WR		(0)
51 
52 #define TSR_CMDAMT	(1 << 31)
53 #define TSR_CMDDMT	(1 << 30)
54 
55 #define RSR_STARY	(1 << 22)
56 #define RSR_STDRY	(1 << 21)
57 
58 #define ACR_DMARX16	(1 << 30)
59 #define ACR_DMATX16	(1 << 29)
60 #define ACR_TX12ATOM	(1 << 26)
61 #define ACR_DMARX20	((1 << 24) | (1 << 22))
62 #define ACR_DMATX20	((1 << 23) | (1 << 21))
63 
64 #define CSDR_SHIFT	4
65 #define CSDR_MASK	(0xffff << CSDR_SHIFT)
66 #define CSAR_SHIFT	12
67 #define CSAR_MASK	(0x7f << CSAR_SHIFT)
68 
69 #define AC97_WRITE_RETRY	1
70 #define AC97_READ_RETRY		5
71 
72 /* manual-suggested AC97 codec access timeouts (us) */
73 #define TMO_E1	500	/* 21 < E1 < 1000 */
74 #define TMO_E2	13	/* 13 < E2 */
75 #define TMO_E3	21	/* 21 < E3 */
76 #define TMO_E4	500	/* 21 < E4 < 1000 */
77 
78 struct hac_priv {
79 	unsigned long mmio;	/* HAC base address */
80 } hac_cpu_data[] = {
81 #if defined(CONFIG_CPU_SUBTYPE_SH7760)
82 	{
83 		.mmio	= 0xFE240000,
84 	},
85 	{
86 		.mmio	= 0xFE250000,
87 	},
88 #elif defined(CONFIG_CPU_SUBTYPE_SH7780)
89 	{
90 		.mmio	= 0xFFE40000,
91 	},
92 #else
93 #error "Unsupported SuperH SoC"
94 #endif
95 };
96 
97 #define HACREG(reg)	(*(unsigned long *)(hac->mmio + (reg)))
98 
99 /*
100  * AC97 read/write flow as outlined in the SH7760 manual (pages 903-906)
101  */
102 static int hac_get_codec_data(struct hac_priv *hac, unsigned short r,
103 			      unsigned short *v)
104 {
105 	unsigned int to1, to2, i;
106 	unsigned short adr;
107 
108 	for (i = 0; i < AC97_READ_RETRY; ++i) {
109 		*v = 0;
110 		/* wait for HAC to receive something from the codec */
111 		for (to1 = TMO_E4;
112 		     to1 && !(HACREG(HACRSR) & RSR_STARY);
113 		     --to1)
114 			udelay(1);
115 		for (to2 = TMO_E4;
116 		     to2 && !(HACREG(HACRSR) & RSR_STDRY);
117 		     --to2)
118 			udelay(1);
119 
120 		if (!to1 && !to2)
121 			return 0;	/* codec comm is down */
122 
123 		adr = ((HACREG(HACCSAR) & CSAR_MASK) >> CSAR_SHIFT);
124 		*v  = ((HACREG(HACCSDR) & CSDR_MASK) >> CSDR_SHIFT);
125 
126 		HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
127 
128 		if (r == adr)
129 			break;
130 
131 		/* manual says: wait at least 21 usec before retrying */
132 		udelay(21);
133 	}
134 	HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
135 	return (i < AC97_READ_RETRY);
136 }
137 
138 static unsigned short hac_read_codec_aux(struct hac_priv *hac,
139 					 unsigned short reg)
140 {
141 	unsigned short val;
142 	unsigned int i, to;
143 
144 	for (i = 0; i < AC97_READ_RETRY; i++) {
145 		/* send_read_request */
146 		local_irq_disable();
147 		HACREG(HACTSR) &= ~(TSR_CMDAMT);
148 		HACREG(HACCSAR) = (reg << CSAR_SHIFT) | CSAR_RD;
149 		local_irq_enable();
150 
151 		for (to = TMO_E3;
152 		     to && !(HACREG(HACTSR) & TSR_CMDAMT);
153 		     --to)
154 			udelay(1);
155 
156 		HACREG(HACTSR) &= ~TSR_CMDAMT;
157 		val = 0;
158 		if (hac_get_codec_data(hac, reg, &val) != 0)
159 			break;
160 	}
161 
162 	if (i == AC97_READ_RETRY)
163 		return ~0;
164 
165 	return val;
166 }
167 
168 static void hac_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
169 			   unsigned short val)
170 {
171 	int unit_id = 0 /* ac97->private_data */;
172 	struct hac_priv *hac = &hac_cpu_data[unit_id];
173 	unsigned int i, to;
174 	/* write_codec_aux */
175 	for (i = 0; i < AC97_WRITE_RETRY; i++) {
176 		/* send_write_request */
177 		local_irq_disable();
178 		HACREG(HACTSR) &= ~(TSR_CMDDMT | TSR_CMDAMT);
179 		HACREG(HACCSDR) = (val << CSDR_SHIFT);
180 		HACREG(HACCSAR) = (reg << CSAR_SHIFT) & (~CSAR_RD);
181 		local_irq_enable();
182 
183 		/* poll-wait for CMDAMT and CMDDMT */
184 		for (to = TMO_E1;
185 		     to && !(HACREG(HACTSR) & (TSR_CMDAMT|TSR_CMDDMT));
186 		     --to)
187 			udelay(1);
188 
189 		HACREG(HACTSR) &= ~(TSR_CMDAMT | TSR_CMDDMT);
190 		if (to)
191 			break;
192 		/* timeout, try again */
193 	}
194 }
195 
196 static unsigned short hac_ac97_read(struct snd_ac97 *ac97,
197 				    unsigned short reg)
198 {
199 	int unit_id = 0 /* ac97->private_data */;
200 	struct hac_priv *hac = &hac_cpu_data[unit_id];
201 	return hac_read_codec_aux(hac, reg);
202 }
203 
204 static void hac_ac97_warmrst(struct snd_ac97 *ac97)
205 {
206 	int unit_id = 0 /* ac97->private_data */;
207 	struct hac_priv *hac = &hac_cpu_data[unit_id];
208 	unsigned int tmo;
209 
210 	HACREG(HACCR) = CR_WMRT | CR_ST | CR_B9;
211 	msleep(10);
212 	HACREG(HACCR) = CR_ST | CR_B9;
213 	for (tmo = 1000; (tmo > 0) && !(HACREG(HACCR) & CR_CR); tmo--)
214 		udelay(1);
215 
216 	if (!tmo)
217 		printk(KERN_INFO "hac: reset: AC97 link down!\n");
218 	/* settings this bit lets us have a conversation with codec */
219 	HACREG(HACACR) |= ACR_TX12ATOM;
220 }
221 
222 static void hac_ac97_coldrst(struct snd_ac97 *ac97)
223 {
224 	int unit_id = 0 /* ac97->private_data */;
225 	struct hac_priv *hac;
226 	hac = &hac_cpu_data[unit_id];
227 
228 	HACREG(HACCR) = 0;
229 	HACREG(HACCR) = CR_CDRT | CR_ST | CR_B9;
230 	msleep(10);
231 	hac_ac97_warmrst(ac97);
232 }
233 
234 struct snd_ac97_bus_ops soc_ac97_ops = {
235 	.read	= hac_ac97_read,
236 	.write	= hac_ac97_write,
237 	.reset	= hac_ac97_coldrst,
238 	.warm_reset = hac_ac97_warmrst,
239 };
240 EXPORT_SYMBOL_GPL(soc_ac97_ops);
241 
242 static int hac_hw_params(struct snd_pcm_substream *substream,
243 			 struct snd_pcm_hw_params *params)
244 {
245 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
246 	struct hac_priv *hac = &hac_cpu_data[rtd->dai->cpu_dai->id];
247 	int d = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1;
248 
249 	switch (params->msbits) {
250 	case 16:
251 		HACREG(HACACR) |= d ?  ACR_DMARX16 :  ACR_DMATX16;
252 		HACREG(HACACR) &= d ? ~ACR_DMARX20 : ~ACR_DMATX20;
253 		break;
254 	case 20:
255 		HACREG(HACACR) &= d ? ~ACR_DMARX16 : ~ACR_DMATX16;
256 		HACREG(HACACR) |= d ?  ACR_DMARX20 :  ACR_DMATX20;
257 		break;
258 	default:
259 		pr_debug("hac: invalid depth %d bit\n", params->msbits);
260 		return -EINVAL;
261 		break;
262 	}
263 
264 	return 0;
265 }
266 
267 #define AC97_RATES	\
268 	SNDRV_PCM_RATE_8000_192000
269 
270 #define AC97_FMTS	\
271 	SNDRV_PCM_FMTBIT_S16_LE
272 
273 struct snd_soc_cpu_dai sh4_hac_dai[] = {
274 {
275 	.name			= "HAC0",
276 	.id			= 0,
277 	.type			= SND_SOC_DAI_AC97,
278 	.playback = {
279 		.rates		= AC97_RATES,
280 		.formats	= AC97_FMTS,
281 		.channels_min	= 2,
282 		.channels_max	= 2,
283 	},
284 	.capture = {
285 		.rates		= AC97_RATES,
286 		.formats	= AC97_FMTS,
287 		.channels_min	= 2,
288 		.channels_max	= 2,
289 	},
290 	.ops = {
291 		.hw_params	= hac_hw_params,
292 	},
293 },
294 #ifdef CONFIG_CPU_SUBTYPE_SH7760
295 {
296 	.name			= "HAC1",
297 	.id			= 1,
298 	.type			= SND_SOC_DAI_AC97,
299 	.playback = {
300 		.rates		= AC97_RATES,
301 		.formats	= AC97_FMTS,
302 		.channels_min	= 2,
303 		.channels_max	= 2,
304 	},
305 	.capture = {
306 		.rates		= AC97_RATES,
307 		.formats	= AC97_FMTS,
308 		.channels_min	= 2,
309 		.channels_max	= 2,
310 	},
311 	.ops = {
312 		.hw_params	= hac_hw_params,
313 	},
314 
315 },
316 #endif
317 };
318 EXPORT_SYMBOL_GPL(sh4_hac_dai);
319 
320 MODULE_LICENSE("GPL");
321 MODULE_DESCRIPTION("SuperH onchip HAC (AC97) audio driver");
322 MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");
323