2 * ASoC driver for Cirrus Logic EP93xx AC97 controller.
4 * Copyright (c) 2010 Mika Westerberg
6 * Based on s3c-ac97 ASoC driver by Jaswinder Singh.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/delay.h>
14 #include <linux/err.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
21 #include <sound/core.h>
22 #include <sound/ac97_codec.h>
23 #include <sound/soc.h>
25 #include <linux/platform_data/dma-ep93xx.h>
28 * Per channel (1-4) registers.
30 #define AC97CH(n) (((n) - 1) * 0x20)
32 #define AC97DR(n) (AC97CH(n) + 0x0000)
34 #define AC97RXCR(n) (AC97CH(n) + 0x0004)
35 #define AC97RXCR_REN BIT(0)
36 #define AC97RXCR_RX3 BIT(3)
37 #define AC97RXCR_RX4 BIT(4)
38 #define AC97RXCR_CM BIT(15)
40 #define AC97TXCR(n) (AC97CH(n) + 0x0008)
41 #define AC97TXCR_TEN BIT(0)
42 #define AC97TXCR_TX3 BIT(3)
43 #define AC97TXCR_TX4 BIT(4)
44 #define AC97TXCR_CM BIT(15)
46 #define AC97SR(n) (AC97CH(n) + 0x000c)
47 #define AC97SR_TXFE BIT(1)
48 #define AC97SR_TXUE BIT(6)
50 #define AC97RISR(n) (AC97CH(n) + 0x0010)
51 #define AC97ISR(n) (AC97CH(n) + 0x0014)
52 #define AC97IE(n) (AC97CH(n) + 0x0018)
55 * Global AC97 controller registers.
57 #define AC97S1DATA 0x0080
58 #define AC97S2DATA 0x0084
59 #define AC97S12DATA 0x0088
61 #define AC97RGIS 0x008c
62 #define AC97GIS 0x0090
65 * Common bits for RGIS, GIS and IM registers.
67 #define AC97_SLOT2RXVALID BIT(1)
68 #define AC97_CODECREADY BIT(5)
69 #define AC97_SLOT2TXCOMPLETE BIT(6)
71 #define AC97EOI 0x0098
72 #define AC97EOI_WINT BIT(0)
73 #define AC97EOI_CODECREADY BIT(1)
75 #define AC97GCR 0x009c
76 #define AC97GCR_AC97IFE BIT(0)
78 #define AC97RESET 0x00a0
79 #define AC97RESET_TIMEDRESET BIT(0)
81 #define AC97SYNC 0x00a4
82 #define AC97SYNC_TIMEDSYNC BIT(0)
84 #define AC97_TIMEOUT msecs_to_jiffies(5)
87 * struct ep93xx_ac97_info - EP93xx AC97 controller info structure
88 * @lock: mutex serializing access to the bus (slot 1 & 2 ops)
89 * @dev: pointer to the platform device dev structure
90 * @regs: mapped AC97 controller registers
91 * @done: bus ops wait here for an interrupt
93 struct ep93xx_ac97_info {
97 struct completion done;
100 /* currently ALSA only supports a single AC97 device */
101 static struct ep93xx_ac97_info *ep93xx_ac97_info;
103 static struct ep93xx_dma_data ep93xx_ac97_pcm_out = {
104 .name = "ac97-pcm-out",
105 .dma_port = EP93XX_DMA_AAC1,
106 .direction = DMA_MEM_TO_DEV,
109 static struct ep93xx_dma_data ep93xx_ac97_pcm_in = {
110 .name = "ac97-pcm-in",
111 .dma_port = EP93XX_DMA_AAC1,
112 .direction = DMA_DEV_TO_MEM,
115 static inline unsigned ep93xx_ac97_read_reg(struct ep93xx_ac97_info *info,
118 return __raw_readl(info->regs + reg);
121 static inline void ep93xx_ac97_write_reg(struct ep93xx_ac97_info *info,
122 unsigned reg, unsigned val)
124 __raw_writel(val, info->regs + reg);
127 static unsigned short ep93xx_ac97_read(struct snd_ac97 *ac97,
130 struct ep93xx_ac97_info *info = ep93xx_ac97_info;
133 mutex_lock(&info->lock);
135 ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
136 ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2RXVALID);
137 if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) {
138 dev_warn(info->dev, "timeout reading register %x\n", reg);
139 mutex_unlock(&info->lock);
142 val = (unsigned short)ep93xx_ac97_read_reg(info, AC97S2DATA);
144 mutex_unlock(&info->lock);
148 static void ep93xx_ac97_write(struct snd_ac97 *ac97,
152 struct ep93xx_ac97_info *info = ep93xx_ac97_info;
154 mutex_lock(&info->lock);
157 * Writes to the codec need to be done so that slot 2 is filled in
160 ep93xx_ac97_write_reg(info, AC97S2DATA, val);
161 ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
163 ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2TXCOMPLETE);
164 if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
165 dev_warn(info->dev, "timeout writing register %x\n", reg);
167 mutex_unlock(&info->lock);
170 static void ep93xx_ac97_warm_reset(struct snd_ac97 *ac97)
172 struct ep93xx_ac97_info *info = ep93xx_ac97_info;
174 mutex_lock(&info->lock);
177 * We are assuming that before this functions gets called, the codec
178 * BIT_CLK is stopped by forcing the codec into powerdown mode. We can
179 * control the SYNC signal directly via AC97SYNC register. Using
180 * TIMEDSYNC the controller will keep the SYNC high > 1us.
182 ep93xx_ac97_write_reg(info, AC97SYNC, AC97SYNC_TIMEDSYNC);
183 ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
184 if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
185 dev_warn(info->dev, "codec warm reset timeout\n");
187 mutex_unlock(&info->lock);
190 static void ep93xx_ac97_cold_reset(struct snd_ac97 *ac97)
192 struct ep93xx_ac97_info *info = ep93xx_ac97_info;
194 mutex_lock(&info->lock);
197 * For doing cold reset, we disable the AC97 controller interface, clear
198 * WINT and CODECREADY bits, and finally enable the interface again.
200 ep93xx_ac97_write_reg(info, AC97GCR, 0);
201 ep93xx_ac97_write_reg(info, AC97EOI, AC97EOI_CODECREADY | AC97EOI_WINT);
202 ep93xx_ac97_write_reg(info, AC97GCR, AC97GCR_AC97IFE);
205 * Now, assert the reset and wait for the codec to become ready.
207 ep93xx_ac97_write_reg(info, AC97RESET, AC97RESET_TIMEDRESET);
208 ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
209 if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
210 dev_warn(info->dev, "codec cold reset timeout\n");
213 * Give the codec some time to come fully out from the reset. This way
214 * we ensure that the subsequent reads/writes will work.
216 usleep_range(15000, 20000);
218 mutex_unlock(&info->lock);
221 static irqreturn_t ep93xx_ac97_interrupt(int irq, void *dev_id)
223 struct ep93xx_ac97_info *info = dev_id;
224 unsigned status, mask;
227 * Just mask out the interrupt and wake up the waiting thread.
228 * Interrupts are cleared via reading/writing to slot 1 & 2 registers by
229 * the waiting thread.
231 status = ep93xx_ac97_read_reg(info, AC97GIS);
232 mask = ep93xx_ac97_read_reg(info, AC97IM);
234 ep93xx_ac97_write_reg(info, AC97IM, mask);
236 complete(&info->done);
240 struct snd_ac97_bus_ops soc_ac97_ops = {
241 .read = ep93xx_ac97_read,
242 .write = ep93xx_ac97_write,
243 .reset = ep93xx_ac97_cold_reset,
244 .warm_reset = ep93xx_ac97_warm_reset,
246 EXPORT_SYMBOL_GPL(soc_ac97_ops);
248 static int ep93xx_ac97_trigger(struct snd_pcm_substream *substream,
249 int cmd, struct snd_soc_dai *dai)
251 struct ep93xx_ac97_info *info = snd_soc_dai_get_drvdata(dai);
255 case SNDRV_PCM_TRIGGER_START:
256 case SNDRV_PCM_TRIGGER_RESUME:
257 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
258 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
260 * Enable compact mode, TX slots 3 & 4, and the TX FIFO
264 v |= AC97TXCR_TX3 | AC97TXCR_TX4;
266 ep93xx_ac97_write_reg(info, AC97TXCR(1), v);
269 * Enable compact mode, RX slots 3 & 4, and the RX FIFO
273 v |= AC97RXCR_RX3 | AC97RXCR_RX4;
275 ep93xx_ac97_write_reg(info, AC97RXCR(1), v);
279 case SNDRV_PCM_TRIGGER_STOP:
280 case SNDRV_PCM_TRIGGER_SUSPEND:
281 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
282 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
284 * As per Cirrus EP93xx errata described below:
286 * http://www.cirrus.com/en/pubs/errata/ER667E2B.pdf
288 * we will wait for the TX FIFO to be empty before
289 * clearing the TEN bit.
291 unsigned long timeout = jiffies + AC97_TIMEOUT;
294 v = ep93xx_ac97_read_reg(info, AC97SR(1));
295 if (time_after(jiffies, timeout)) {
296 dev_warn(info->dev, "TX timeout\n");
299 } while (!(v & (AC97SR_TXFE | AC97SR_TXUE)));
301 /* disable the TX FIFO */
302 ep93xx_ac97_write_reg(info, AC97TXCR(1), 0);
304 /* disable the RX FIFO */
305 ep93xx_ac97_write_reg(info, AC97RXCR(1), 0);
310 dev_warn(info->dev, "unknown command %d\n", cmd);
317 static int ep93xx_ac97_dai_probe(struct snd_soc_dai *dai)
319 dai->playback_dma_data = &ep93xx_ac97_pcm_out;
320 dai->capture_dma_data = &ep93xx_ac97_pcm_in;
325 static const struct snd_soc_dai_ops ep93xx_ac97_dai_ops = {
326 .trigger = ep93xx_ac97_trigger,
329 static struct snd_soc_dai_driver ep93xx_ac97_dai = {
330 .name = "ep93xx-ac97",
333 .probe = ep93xx_ac97_dai_probe,
335 .stream_name = "AC97 Playback",
338 .rates = SNDRV_PCM_RATE_8000_48000,
339 .formats = SNDRV_PCM_FMTBIT_S16_LE,
342 .stream_name = "AC97 Capture",
345 .rates = SNDRV_PCM_RATE_8000_48000,
346 .formats = SNDRV_PCM_FMTBIT_S16_LE,
348 .ops = &ep93xx_ac97_dai_ops,
351 static const struct snd_soc_component_driver ep93xx_ac97_component = {
352 .name = "ep93xx-ac97",
355 static int ep93xx_ac97_probe(struct platform_device *pdev)
357 struct ep93xx_ac97_info *info;
358 struct resource *res;
362 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
366 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
370 info->regs = devm_ioremap_resource(&pdev->dev, res);
371 if (IS_ERR(info->regs))
372 return PTR_ERR(info->regs);
374 irq = platform_get_irq(pdev, 0);
378 ret = devm_request_irq(&pdev->dev, irq, ep93xx_ac97_interrupt,
379 IRQF_TRIGGER_HIGH, pdev->name, info);
383 dev_set_drvdata(&pdev->dev, info);
385 mutex_init(&info->lock);
386 init_completion(&info->done);
387 info->dev = &pdev->dev;
389 ep93xx_ac97_info = info;
390 platform_set_drvdata(pdev, info);
392 ret = snd_soc_register_component(&pdev->dev, &ep93xx_ac97_component,
393 &ep93xx_ac97_dai, 1);
400 ep93xx_ac97_info = NULL;
401 dev_set_drvdata(&pdev->dev, NULL);
405 static int ep93xx_ac97_remove(struct platform_device *pdev)
407 struct ep93xx_ac97_info *info = platform_get_drvdata(pdev);
409 snd_soc_unregister_component(&pdev->dev);
411 /* disable the AC97 controller */
412 ep93xx_ac97_write_reg(info, AC97GCR, 0);
414 ep93xx_ac97_info = NULL;
415 dev_set_drvdata(&pdev->dev, NULL);
420 static struct platform_driver ep93xx_ac97_driver = {
421 .probe = ep93xx_ac97_probe,
422 .remove = ep93xx_ac97_remove,
424 .name = "ep93xx-ac97",
425 .owner = THIS_MODULE,
429 module_platform_driver(ep93xx_ac97_driver);
431 MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver");
432 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
433 MODULE_LICENSE("GPL");
434 MODULE_ALIAS("platform:ep93xx-ac97");