cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ac97c.c (22438B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Driver for Atmel AC97C
      4 *
      5 * Copyright (C) 2005-2009 Atmel Corporation
      6 */
      7#include <linux/clk.h>
      8#include <linux/delay.h>
      9#include <linux/bitmap.h>
     10#include <linux/device.h>
     11#include <linux/atmel_pdc.h>
     12#include <linux/gpio/consumer.h>
     13#include <linux/init.h>
     14#include <linux/interrupt.h>
     15#include <linux/module.h>
     16#include <linux/platform_device.h>
     17#include <linux/mutex.h>
     18#include <linux/types.h>
     19#include <linux/io.h>
     20#include <linux/of.h>
     21#include <linux/of_device.h>
     22
     23#include <sound/core.h>
     24#include <sound/initval.h>
     25#include <sound/pcm.h>
     26#include <sound/pcm_params.h>
     27#include <sound/ac97_codec.h>
     28#include <sound/memalloc.h>
     29
     30#include "ac97c.h"
     31
     32/* Serialize access to opened variable */
     33static DEFINE_MUTEX(opened_mutex);
     34
     35struct atmel_ac97c {
     36	struct clk			*pclk;
     37	struct platform_device		*pdev;
     38
     39	struct snd_pcm_substream	*playback_substream;
     40	struct snd_pcm_substream	*capture_substream;
     41	struct snd_card			*card;
     42	struct snd_pcm			*pcm;
     43	struct snd_ac97			*ac97;
     44	struct snd_ac97_bus		*ac97_bus;
     45
     46	u64				cur_format;
     47	unsigned int			cur_rate;
     48	int				playback_period, capture_period;
     49	/* Serialize access to opened variable */
     50	spinlock_t			lock;
     51	void __iomem			*regs;
     52	int				irq;
     53	int				opened;
     54	struct gpio_desc		*reset_pin;
     55};
     56
     57#define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
     58
     59#define ac97c_writel(chip, reg, val)			\
     60	__raw_writel((val), (chip)->regs + AC97C_##reg)
     61#define ac97c_readl(chip, reg)				\
     62	__raw_readl((chip)->regs + AC97C_##reg)
     63
     64static const struct snd_pcm_hardware atmel_ac97c_hw = {
     65	.info			= (SNDRV_PCM_INFO_MMAP
     66				  | SNDRV_PCM_INFO_MMAP_VALID
     67				  | SNDRV_PCM_INFO_INTERLEAVED
     68				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
     69				  | SNDRV_PCM_INFO_JOINT_DUPLEX
     70				  | SNDRV_PCM_INFO_RESUME
     71				  | SNDRV_PCM_INFO_PAUSE),
     72	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
     73				  | SNDRV_PCM_FMTBIT_S16_LE),
     74	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
     75	.rate_min		= 4000,
     76	.rate_max		= 48000,
     77	.channels_min		= 1,
     78	.channels_max		= 2,
     79	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
     80	.period_bytes_min	= 4096,
     81	.period_bytes_max	= 4096,
     82	.periods_min		= 6,
     83	.periods_max		= 64,
     84};
     85
     86static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
     87{
     88	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
     89	struct snd_pcm_runtime *runtime = substream->runtime;
     90
     91	mutex_lock(&opened_mutex);
     92	chip->opened++;
     93	runtime->hw = atmel_ac97c_hw;
     94	if (chip->cur_rate) {
     95		runtime->hw.rate_min = chip->cur_rate;
     96		runtime->hw.rate_max = chip->cur_rate;
     97	}
     98	if (chip->cur_format)
     99		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
    100	mutex_unlock(&opened_mutex);
    101	chip->playback_substream = substream;
    102	return 0;
    103}
    104
    105static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
    106{
    107	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    108	struct snd_pcm_runtime *runtime = substream->runtime;
    109
    110	mutex_lock(&opened_mutex);
    111	chip->opened++;
    112	runtime->hw = atmel_ac97c_hw;
    113	if (chip->cur_rate) {
    114		runtime->hw.rate_min = chip->cur_rate;
    115		runtime->hw.rate_max = chip->cur_rate;
    116	}
    117	if (chip->cur_format)
    118		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
    119	mutex_unlock(&opened_mutex);
    120	chip->capture_substream = substream;
    121	return 0;
    122}
    123
    124static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
    125{
    126	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    127
    128	mutex_lock(&opened_mutex);
    129	chip->opened--;
    130	if (!chip->opened) {
    131		chip->cur_rate = 0;
    132		chip->cur_format = 0;
    133	}
    134	mutex_unlock(&opened_mutex);
    135
    136	chip->playback_substream = NULL;
    137
    138	return 0;
    139}
    140
    141static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
    142{
    143	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    144
    145	mutex_lock(&opened_mutex);
    146	chip->opened--;
    147	if (!chip->opened) {
    148		chip->cur_rate = 0;
    149		chip->cur_format = 0;
    150	}
    151	mutex_unlock(&opened_mutex);
    152
    153	chip->capture_substream = NULL;
    154
    155	return 0;
    156}
    157
    158static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
    159		struct snd_pcm_hw_params *hw_params)
    160{
    161	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    162
    163	/* Set restrictions to params. */
    164	mutex_lock(&opened_mutex);
    165	chip->cur_rate = params_rate(hw_params);
    166	chip->cur_format = params_format(hw_params);
    167	mutex_unlock(&opened_mutex);
    168
    169	return 0;
    170}
    171
    172static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
    173		struct snd_pcm_hw_params *hw_params)
    174{
    175	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    176
    177	/* Set restrictions to params. */
    178	mutex_lock(&opened_mutex);
    179	chip->cur_rate = params_rate(hw_params);
    180	chip->cur_format = params_format(hw_params);
    181	mutex_unlock(&opened_mutex);
    182
    183	return 0;
    184}
    185
    186static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
    187{
    188	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    189	struct snd_pcm_runtime *runtime = substream->runtime;
    190	int block_size = frames_to_bytes(runtime, runtime->period_size);
    191	unsigned long word = ac97c_readl(chip, OCA);
    192	int retval;
    193
    194	chip->playback_period = 0;
    195	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
    196
    197	/* assign channels to AC97C channel A */
    198	switch (runtime->channels) {
    199	case 1:
    200		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
    201		break;
    202	case 2:
    203		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
    204			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
    205		break;
    206	default:
    207		/* TODO: support more than two channels */
    208		return -EINVAL;
    209	}
    210	ac97c_writel(chip, OCA, word);
    211
    212	/* configure sample format and size */
    213	word = ac97c_readl(chip, CAMR);
    214	if (chip->opened <= 1)
    215		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
    216	else
    217		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
    218
    219	switch (runtime->format) {
    220	case SNDRV_PCM_FORMAT_S16_LE:
    221		break;
    222	case SNDRV_PCM_FORMAT_S16_BE:
    223		word &= ~(AC97C_CMR_CEM_LITTLE);
    224		break;
    225	default:
    226		word = ac97c_readl(chip, OCA);
    227		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
    228		ac97c_writel(chip, OCA, word);
    229		return -EINVAL;
    230	}
    231
    232	/* Enable underrun interrupt on channel A */
    233	word |= AC97C_CSR_UNRUN;
    234
    235	ac97c_writel(chip, CAMR, word);
    236
    237	/* Enable channel A event interrupt */
    238	word = ac97c_readl(chip, IMR);
    239	word |= AC97C_SR_CAEVT;
    240	ac97c_writel(chip, IER, word);
    241
    242	/* set variable rate if needed */
    243	if (runtime->rate != 48000) {
    244		word = ac97c_readl(chip, MR);
    245		word |= AC97C_MR_VRA;
    246		ac97c_writel(chip, MR, word);
    247	} else {
    248		word = ac97c_readl(chip, MR);
    249		word &= ~(AC97C_MR_VRA);
    250		ac97c_writel(chip, MR, word);
    251	}
    252
    253	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
    254			runtime->rate);
    255	if (retval)
    256		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
    257				runtime->rate);
    258
    259	/* Initialize and start the PDC */
    260	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
    261	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
    262	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
    263	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
    264
    265	return retval;
    266}
    267
    268static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
    269{
    270	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    271	struct snd_pcm_runtime *runtime = substream->runtime;
    272	int block_size = frames_to_bytes(runtime, runtime->period_size);
    273	unsigned long word = ac97c_readl(chip, ICA);
    274	int retval;
    275
    276	chip->capture_period = 0;
    277	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
    278
    279	/* assign channels to AC97C channel A */
    280	switch (runtime->channels) {
    281	case 1:
    282		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
    283		break;
    284	case 2:
    285		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
    286			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
    287		break;
    288	default:
    289		/* TODO: support more than two channels */
    290		return -EINVAL;
    291	}
    292	ac97c_writel(chip, ICA, word);
    293
    294	/* configure sample format and size */
    295	word = ac97c_readl(chip, CAMR);
    296	if (chip->opened <= 1)
    297		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
    298	else
    299		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
    300
    301	switch (runtime->format) {
    302	case SNDRV_PCM_FORMAT_S16_LE:
    303		break;
    304	case SNDRV_PCM_FORMAT_S16_BE:
    305		word &= ~(AC97C_CMR_CEM_LITTLE);
    306		break;
    307	default:
    308		word = ac97c_readl(chip, ICA);
    309		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
    310		ac97c_writel(chip, ICA, word);
    311		return -EINVAL;
    312	}
    313
    314	/* Enable overrun interrupt on channel A */
    315	word |= AC97C_CSR_OVRUN;
    316
    317	ac97c_writel(chip, CAMR, word);
    318
    319	/* Enable channel A event interrupt */
    320	word = ac97c_readl(chip, IMR);
    321	word |= AC97C_SR_CAEVT;
    322	ac97c_writel(chip, IER, word);
    323
    324	/* set variable rate if needed */
    325	if (runtime->rate != 48000) {
    326		word = ac97c_readl(chip, MR);
    327		word |= AC97C_MR_VRA;
    328		ac97c_writel(chip, MR, word);
    329	} else {
    330		word = ac97c_readl(chip, MR);
    331		word &= ~(AC97C_MR_VRA);
    332		ac97c_writel(chip, MR, word);
    333	}
    334
    335	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
    336			runtime->rate);
    337	if (retval)
    338		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
    339				runtime->rate);
    340
    341	/* Initialize and start the PDC */
    342	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
    343	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
    344	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
    345	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
    346
    347	return retval;
    348}
    349
    350static int
    351atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
    352{
    353	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    354	unsigned long camr, ptcr = 0;
    355
    356	camr = ac97c_readl(chip, CAMR);
    357
    358	switch (cmd) {
    359	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
    360	case SNDRV_PCM_TRIGGER_RESUME:
    361	case SNDRV_PCM_TRIGGER_START:
    362		ptcr = ATMEL_PDC_TXTEN;
    363		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
    364		break;
    365	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
    366	case SNDRV_PCM_TRIGGER_SUSPEND:
    367	case SNDRV_PCM_TRIGGER_STOP:
    368		ptcr |= ATMEL_PDC_TXTDIS;
    369		if (chip->opened <= 1)
    370			camr &= ~AC97C_CMR_CENA;
    371		break;
    372	default:
    373		return -EINVAL;
    374	}
    375
    376	ac97c_writel(chip, CAMR, camr);
    377	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
    378	return 0;
    379}
    380
    381static int
    382atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
    383{
    384	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
    385	unsigned long camr, ptcr = 0;
    386
    387	camr = ac97c_readl(chip, CAMR);
    388	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
    389
    390	switch (cmd) {
    391	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
    392	case SNDRV_PCM_TRIGGER_RESUME:
    393	case SNDRV_PCM_TRIGGER_START:
    394		ptcr = ATMEL_PDC_RXTEN;
    395		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
    396		break;
    397	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
    398	case SNDRV_PCM_TRIGGER_SUSPEND:
    399	case SNDRV_PCM_TRIGGER_STOP:
    400		ptcr |= ATMEL_PDC_RXTDIS;
    401		if (chip->opened <= 1)
    402			camr &= ~AC97C_CMR_CENA;
    403		break;
    404	default:
    405		return -EINVAL;
    406	}
    407
    408	ac97c_writel(chip, CAMR, camr);
    409	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
    410	return 0;
    411}
    412
    413static snd_pcm_uframes_t
    414atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
    415{
    416	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
    417	struct snd_pcm_runtime	*runtime = substream->runtime;
    418	snd_pcm_uframes_t	frames;
    419	unsigned long		bytes;
    420
    421	bytes = readl(chip->regs + ATMEL_PDC_TPR);
    422	bytes -= runtime->dma_addr;
    423
    424	frames = bytes_to_frames(runtime, bytes);
    425	if (frames >= runtime->buffer_size)
    426		frames -= runtime->buffer_size;
    427	return frames;
    428}
    429
    430static snd_pcm_uframes_t
    431atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
    432{
    433	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
    434	struct snd_pcm_runtime	*runtime = substream->runtime;
    435	snd_pcm_uframes_t	frames;
    436	unsigned long		bytes;
    437
    438	bytes = readl(chip->regs + ATMEL_PDC_RPR);
    439	bytes -= runtime->dma_addr;
    440
    441	frames = bytes_to_frames(runtime, bytes);
    442	if (frames >= runtime->buffer_size)
    443		frames -= runtime->buffer_size;
    444	return frames;
    445}
    446
    447static const struct snd_pcm_ops atmel_ac97_playback_ops = {
    448	.open		= atmel_ac97c_playback_open,
    449	.close		= atmel_ac97c_playback_close,
    450	.hw_params	= atmel_ac97c_playback_hw_params,
    451	.prepare	= atmel_ac97c_playback_prepare,
    452	.trigger	= atmel_ac97c_playback_trigger,
    453	.pointer	= atmel_ac97c_playback_pointer,
    454};
    455
    456static const struct snd_pcm_ops atmel_ac97_capture_ops = {
    457	.open		= atmel_ac97c_capture_open,
    458	.close		= atmel_ac97c_capture_close,
    459	.hw_params	= atmel_ac97c_capture_hw_params,
    460	.prepare	= atmel_ac97c_capture_prepare,
    461	.trigger	= atmel_ac97c_capture_trigger,
    462	.pointer	= atmel_ac97c_capture_pointer,
    463};
    464
    465static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
    466{
    467	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
    468	irqreturn_t		retval = IRQ_NONE;
    469	u32			sr     = ac97c_readl(chip, SR);
    470	u32			casr   = ac97c_readl(chip, CASR);
    471	u32			cosr   = ac97c_readl(chip, COSR);
    472	u32			camr   = ac97c_readl(chip, CAMR);
    473
    474	if (sr & AC97C_SR_CAEVT) {
    475		struct snd_pcm_runtime *runtime;
    476		int offset, next_period, block_size;
    477		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
    478			(casr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
    479			(casr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
    480			(casr & AC97C_CSR_UNRUN)   ? " UNRUN"   : "",
    481			(casr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
    482			(casr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
    483			!casr                      ? " NONE"    : "");
    484		if ((casr & camr) & AC97C_CSR_ENDTX) {
    485			runtime = chip->playback_substream->runtime;
    486			block_size = frames_to_bytes(runtime, runtime->period_size);
    487			chip->playback_period++;
    488
    489			if (chip->playback_period == runtime->periods)
    490				chip->playback_period = 0;
    491			next_period = chip->playback_period + 1;
    492			if (next_period == runtime->periods)
    493				next_period = 0;
    494
    495			offset = block_size * next_period;
    496
    497			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
    498			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
    499
    500			snd_pcm_period_elapsed(chip->playback_substream);
    501		}
    502		if ((casr & camr) & AC97C_CSR_ENDRX) {
    503			runtime = chip->capture_substream->runtime;
    504			block_size = frames_to_bytes(runtime, runtime->period_size);
    505			chip->capture_period++;
    506
    507			if (chip->capture_period == runtime->periods)
    508				chip->capture_period = 0;
    509			next_period = chip->capture_period + 1;
    510			if (next_period == runtime->periods)
    511				next_period = 0;
    512
    513			offset = block_size * next_period;
    514
    515			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
    516			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
    517			snd_pcm_period_elapsed(chip->capture_substream);
    518		}
    519		retval = IRQ_HANDLED;
    520	}
    521
    522	if (sr & AC97C_SR_COEVT) {
    523		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
    524			 (cosr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
    525			 (cosr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
    526			 (cosr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
    527			 (cosr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
    528			 !cosr                      ? " NONE"    : "");
    529		retval = IRQ_HANDLED;
    530	}
    531
    532	if (retval == IRQ_NONE) {
    533		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
    534				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
    535	}
    536
    537	return retval;
    538}
    539
    540static const struct ac97_pcm at91_ac97_pcm_defs[] = {
    541	/* Playback */
    542	{
    543		.exclusive = 1,
    544		.r = { {
    545			.slots = ((1 << AC97_SLOT_PCM_LEFT)
    546				  | (1 << AC97_SLOT_PCM_RIGHT)),
    547		} },
    548	},
    549	/* PCM in */
    550	{
    551		.stream = 1,
    552		.exclusive = 1,
    553		.r = { {
    554			.slots = ((1 << AC97_SLOT_PCM_LEFT)
    555					| (1 << AC97_SLOT_PCM_RIGHT)),
    556		} }
    557	},
    558	/* Mic in */
    559	{
    560		.stream = 1,
    561		.exclusive = 1,
    562		.r = { {
    563			.slots = (1<<AC97_SLOT_MIC),
    564		} }
    565	},
    566};
    567
    568static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
    569{
    570	struct snd_pcm		*pcm;
    571	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
    572	int			retval;
    573
    574	retval = snd_ac97_pcm_assign(chip->ac97_bus,
    575				     ARRAY_SIZE(at91_ac97_pcm_defs),
    576				     at91_ac97_pcm_defs);
    577	if (retval)
    578		return retval;
    579
    580	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
    581	if (retval)
    582		return retval;
    583
    584	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
    585	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
    586
    587	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
    588			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
    589			hw.buffer_bytes_max);
    590
    591	pcm->private_data = chip;
    592	pcm->info_flags = 0;
    593	strcpy(pcm->name, chip->card->shortname);
    594	chip->pcm = pcm;
    595
    596	return 0;
    597}
    598
    599static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
    600{
    601	struct snd_ac97_template template;
    602	memset(&template, 0, sizeof(template));
    603	template.private_data = chip;
    604	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
    605}
    606
    607static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
    608		unsigned short val)
    609{
    610	struct atmel_ac97c *chip = get_chip(ac97);
    611	unsigned long word;
    612	int timeout = 40;
    613
    614	word = (reg & 0x7f) << 16 | val;
    615
    616	do {
    617		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
    618			ac97c_writel(chip, COTHR, word);
    619			return;
    620		}
    621		udelay(1);
    622	} while (--timeout);
    623
    624	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
    625}
    626
    627static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
    628		unsigned short reg)
    629{
    630	struct atmel_ac97c *chip = get_chip(ac97);
    631	unsigned long word;
    632	int timeout = 40;
    633	int write = 10;
    634
    635	word = (0x80 | (reg & 0x7f)) << 16;
    636
    637	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
    638		ac97c_readl(chip, CORHR);
    639
    640retry_write:
    641	timeout = 40;
    642
    643	do {
    644		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
    645			ac97c_writel(chip, COTHR, word);
    646			goto read_reg;
    647		}
    648		udelay(10);
    649	} while (--timeout);
    650
    651	if (!--write)
    652		goto timed_out;
    653	goto retry_write;
    654
    655read_reg:
    656	do {
    657		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
    658			unsigned short val = ac97c_readl(chip, CORHR);
    659			return val;
    660		}
    661		udelay(10);
    662	} while (--timeout);
    663
    664	if (!--write)
    665		goto timed_out;
    666	goto retry_write;
    667
    668timed_out:
    669	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
    670	return 0xffff;
    671}
    672
    673static void atmel_ac97c_reset(struct atmel_ac97c *chip)
    674{
    675	ac97c_writel(chip, MR,   0);
    676	ac97c_writel(chip, MR,   AC97C_MR_ENA);
    677	ac97c_writel(chip, CAMR, 0);
    678	ac97c_writel(chip, COMR, 0);
    679
    680	if (!IS_ERR(chip->reset_pin)) {
    681		gpiod_set_value(chip->reset_pin, 0);
    682		/* AC97 v2.2 specifications says minimum 1 us. */
    683		udelay(2);
    684		gpiod_set_value(chip->reset_pin, 1);
    685	} else {
    686		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
    687		udelay(2);
    688		ac97c_writel(chip, MR, AC97C_MR_ENA);
    689	}
    690}
    691
    692static const struct of_device_id atmel_ac97c_dt_ids[] = {
    693	{ .compatible = "atmel,at91sam9263-ac97c", },
    694	{ }
    695};
    696MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
    697
    698static int atmel_ac97c_probe(struct platform_device *pdev)
    699{
    700	struct device			*dev = &pdev->dev;
    701	struct snd_card			*card;
    702	struct atmel_ac97c		*chip;
    703	struct resource			*regs;
    704	struct clk			*pclk;
    705	static const struct snd_ac97_bus_ops	ops = {
    706		.write	= atmel_ac97c_write,
    707		.read	= atmel_ac97c_read,
    708	};
    709	int				retval;
    710	int				irq;
    711
    712	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    713	if (!regs) {
    714		dev_dbg(&pdev->dev, "no memory resource\n");
    715		return -ENXIO;
    716	}
    717
    718	irq = platform_get_irq(pdev, 0);
    719	if (irq < 0) {
    720		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
    721		return irq;
    722	}
    723
    724	pclk = clk_get(&pdev->dev, "ac97_clk");
    725	if (IS_ERR(pclk)) {
    726		dev_dbg(&pdev->dev, "no peripheral clock\n");
    727		return PTR_ERR(pclk);
    728	}
    729	retval = clk_prepare_enable(pclk);
    730	if (retval)
    731		goto err_prepare_enable;
    732
    733	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
    734			      SNDRV_DEFAULT_STR1, THIS_MODULE,
    735			      sizeof(struct atmel_ac97c), &card);
    736	if (retval) {
    737		dev_dbg(&pdev->dev, "could not create sound card device\n");
    738		goto err_snd_card_new;
    739	}
    740
    741	chip = get_chip(card);
    742
    743	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
    744	if (retval) {
    745		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
    746		goto err_request_irq;
    747	}
    748	chip->irq = irq;
    749
    750	spin_lock_init(&chip->lock);
    751
    752	strcpy(card->driver, "Atmel AC97C");
    753	strcpy(card->shortname, "Atmel AC97C");
    754	sprintf(card->longname, "Atmel AC97 controller");
    755
    756	chip->card = card;
    757	chip->pclk = pclk;
    758	chip->pdev = pdev;
    759	chip->regs = ioremap(regs->start, resource_size(regs));
    760
    761	if (!chip->regs) {
    762		dev_dbg(&pdev->dev, "could not remap register memory\n");
    763		retval = -ENOMEM;
    764		goto err_ioremap;
    765	}
    766
    767	chip->reset_pin = devm_gpiod_get_index(dev, "ac97", 2, GPIOD_OUT_HIGH);
    768	if (IS_ERR(chip->reset_pin))
    769		dev_dbg(dev, "reset pin not available\n");
    770
    771	atmel_ac97c_reset(chip);
    772
    773	/* Enable overrun interrupt from codec channel */
    774	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
    775	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
    776
    777	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
    778	if (retval) {
    779		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
    780		goto err_ac97_bus;
    781	}
    782
    783	retval = atmel_ac97c_mixer_new(chip);
    784	if (retval) {
    785		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
    786		goto err_ac97_bus;
    787	}
    788
    789	retval = atmel_ac97c_pcm_new(chip);
    790	if (retval) {
    791		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
    792		goto err_ac97_bus;
    793	}
    794
    795	retval = snd_card_register(card);
    796	if (retval) {
    797		dev_dbg(&pdev->dev, "could not register sound card\n");
    798		goto err_ac97_bus;
    799	}
    800
    801	platform_set_drvdata(pdev, card);
    802
    803	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
    804			chip->regs, irq);
    805
    806	return 0;
    807
    808err_ac97_bus:
    809	iounmap(chip->regs);
    810err_ioremap:
    811	free_irq(irq, chip);
    812err_request_irq:
    813	snd_card_free(card);
    814err_snd_card_new:
    815	clk_disable_unprepare(pclk);
    816err_prepare_enable:
    817	clk_put(pclk);
    818	return retval;
    819}
    820
    821#ifdef CONFIG_PM_SLEEP
    822static int atmel_ac97c_suspend(struct device *pdev)
    823{
    824	struct snd_card *card = dev_get_drvdata(pdev);
    825	struct atmel_ac97c *chip = card->private_data;
    826
    827	clk_disable_unprepare(chip->pclk);
    828	return 0;
    829}
    830
    831static int atmel_ac97c_resume(struct device *pdev)
    832{
    833	struct snd_card *card = dev_get_drvdata(pdev);
    834	struct atmel_ac97c *chip = card->private_data;
    835	int ret = clk_prepare_enable(chip->pclk);
    836
    837	return ret;
    838}
    839
    840static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
    841#define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
    842#else
    843#define ATMEL_AC97C_PM_OPS	NULL
    844#endif
    845
    846static int atmel_ac97c_remove(struct platform_device *pdev)
    847{
    848	struct snd_card *card = platform_get_drvdata(pdev);
    849	struct atmel_ac97c *chip = get_chip(card);
    850
    851	ac97c_writel(chip, CAMR, 0);
    852	ac97c_writel(chip, COMR, 0);
    853	ac97c_writel(chip, MR,   0);
    854
    855	clk_disable_unprepare(chip->pclk);
    856	clk_put(chip->pclk);
    857	iounmap(chip->regs);
    858	free_irq(chip->irq, chip);
    859
    860	snd_card_free(card);
    861
    862	return 0;
    863}
    864
    865static struct platform_driver atmel_ac97c_driver = {
    866	.probe		= atmel_ac97c_probe,
    867	.remove		= atmel_ac97c_remove,
    868	.driver		= {
    869		.name	= "atmel_ac97c",
    870		.pm	= ATMEL_AC97C_PM_OPS,
    871		.of_match_table = atmel_ac97c_dt_ids,
    872	},
    873};
    874module_platform_driver(atmel_ac97c_driver);
    875
    876MODULE_LICENSE("GPL");
    877MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
    878MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");