diff options
Diffstat (limited to 'sound/soc/cirrus/ep93xx-ac97.c')
| -rw-r--r-- | sound/soc/cirrus/ep93xx-ac97.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/sound/soc/cirrus/ep93xx-ac97.c b/sound/soc/cirrus/ep93xx-ac97.c new file mode 100644 index 00000000000..c3521653cfd --- /dev/null +++ b/sound/soc/cirrus/ep93xx-ac97.c @@ -0,0 +1,435 @@ +/* + * ASoC driver for Cirrus Logic EP93xx AC97 controller. + * + * Copyright (c) 2010 Mika Westerberg + * + * Based on s3c-ac97 ASoC driver by Jaswinder Singh. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include <sound/core.h> +#include <sound/ac97_codec.h> +#include <sound/soc.h> + +#include <linux/platform_data/dma-ep93xx.h> +#include "ep93xx-pcm.h" + +/* + * Per channel (1-4) registers. + */ +#define AC97CH(n) (((n) - 1) * 0x20) + +#define AC97DR(n) (AC97CH(n) + 0x0000) + +#define AC97RXCR(n) (AC97CH(n) + 0x0004) +#define AC97RXCR_REN BIT(0) +#define AC97RXCR_RX3 BIT(3) +#define AC97RXCR_RX4 BIT(4) +#define AC97RXCR_CM BIT(15) + +#define AC97TXCR(n) (AC97CH(n) + 0x0008) +#define AC97TXCR_TEN BIT(0) +#define AC97TXCR_TX3 BIT(3) +#define AC97TXCR_TX4 BIT(4) +#define AC97TXCR_CM BIT(15) + +#define AC97SR(n) (AC97CH(n) + 0x000c) +#define AC97SR_TXFE BIT(1) +#define AC97SR_TXUE BIT(6) + +#define AC97RISR(n) (AC97CH(n) + 0x0010) +#define AC97ISR(n) (AC97CH(n) + 0x0014) +#define AC97IE(n) (AC97CH(n) + 0x0018) + +/* + * Global AC97 controller registers. + */ +#define AC97S1DATA 0x0080 +#define AC97S2DATA 0x0084 +#define AC97S12DATA 0x0088 + +#define AC97RGIS 0x008c +#define AC97GIS 0x0090 +#define AC97IM 0x0094 +/* + * Common bits for RGIS, GIS and IM registers. + */ +#define AC97_SLOT2RXVALID BIT(1) +#define AC97_CODECREADY BIT(5) +#define AC97_SLOT2TXCOMPLETE BIT(6) + +#define AC97EOI 0x0098 +#define AC97EOI_WINT BIT(0) +#define AC97EOI_CODECREADY BIT(1) + +#define AC97GCR 0x009c +#define AC97GCR_AC97IFE BIT(0) + +#define AC97RESET 0x00a0 +#define AC97RESET_TIMEDRESET BIT(0) + +#define AC97SYNC 0x00a4 +#define AC97SYNC_TIMEDSYNC BIT(0) + +#define AC97_TIMEOUT msecs_to_jiffies(5) + +/** + * struct ep93xx_ac97_info - EP93xx AC97 controller info structure + * @lock: mutex serializing access to the bus (slot 1 & 2 ops) + * @dev: pointer to the platform device dev structure + * @regs: mapped AC97 controller registers + * @done: bus ops wait here for an interrupt + */ +struct ep93xx_ac97_info { + struct mutex lock; + struct device *dev; + void __iomem *regs; + struct completion done; +}; + +/* currently ALSA only supports a single AC97 device */ +static struct ep93xx_ac97_info *ep93xx_ac97_info; + +static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_out = { + .name = "ac97-pcm-out", + .dma_port = EP93XX_DMA_AAC1, +}; + +static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_in = { + .name = "ac97-pcm-in", + .dma_port = EP93XX_DMA_AAC1, +}; + +static inline unsigned ep93xx_ac97_read_reg(struct ep93xx_ac97_info *info, + unsigned reg) +{ + return __raw_readl(info->regs + reg); +} + +static inline void ep93xx_ac97_write_reg(struct ep93xx_ac97_info *info, + unsigned reg, unsigned val) +{ + __raw_writel(val, info->regs + reg); +} + +static unsigned short ep93xx_ac97_read(struct snd_ac97 *ac97, + unsigned short reg) +{ + struct ep93xx_ac97_info *info = ep93xx_ac97_info; + unsigned short val; + + mutex_lock(&info->lock); + + ep93xx_ac97_write_reg(info, AC97S1DATA, reg); + ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2RXVALID); + if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) { + dev_warn(info->dev, "timeout reading register %x\n", reg); + mutex_unlock(&info->lock); + return -ETIMEDOUT; + } + val = (unsigned short)ep93xx_ac97_read_reg(info, AC97S2DATA); + + mutex_unlock(&info->lock); + return val; +} + +static void ep93xx_ac97_write(struct snd_ac97 *ac97, + unsigned short reg, + unsigned short val) +{ + struct ep93xx_ac97_info *info = ep93xx_ac97_info; + + mutex_lock(&info->lock); + + /* + * Writes to the codec need to be done so that slot 2 is filled in + * before slot 1. + */ + ep93xx_ac97_write_reg(info, AC97S2DATA, val); + ep93xx_ac97_write_reg(info, AC97S1DATA, reg); + + ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2TXCOMPLETE); + if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) + dev_warn(info->dev, "timeout writing register %x\n", reg); + + mutex_unlock(&info->lock); +} + +static void ep93xx_ac97_warm_reset(struct snd_ac97 *ac97) +{ + struct ep93xx_ac97_info *info = ep93xx_ac97_info; + + mutex_lock(&info->lock); + + /* + * We are assuming that before this functions gets called, the codec + * BIT_CLK is stopped by forcing the codec into powerdown mode. We can + * control the SYNC signal directly via AC97SYNC register. Using + * TIMEDSYNC the controller will keep the SYNC high > 1us. + */ + ep93xx_ac97_write_reg(info, AC97SYNC, AC97SYNC_TIMEDSYNC); + ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY); + if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) + dev_warn(info->dev, "codec warm reset timeout\n"); + + mutex_unlock(&info->lock); +} + +static void ep93xx_ac97_cold_reset(struct snd_ac97 *ac97) +{ + struct ep93xx_ac97_info *info = ep93xx_ac97_info; + + mutex_lock(&info->lock); + + /* + * For doing cold reset, we disable the AC97 controller interface, clear + * WINT and CODECREADY bits, and finally enable the interface again. + */ + ep93xx_ac97_write_reg(info, AC97GCR, 0); + ep93xx_ac97_write_reg(info, AC97EOI, AC97EOI_CODECREADY | AC97EOI_WINT); + ep93xx_ac97_write_reg(info, AC97GCR, AC97GCR_AC97IFE); + + /* + * Now, assert the reset and wait for the codec to become ready. + */ + ep93xx_ac97_write_reg(info, AC97RESET, AC97RESET_TIMEDRESET); + ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY); + if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) + dev_warn(info->dev, "codec cold reset timeout\n"); + + /* + * Give the codec some time to come fully out from the reset. This way + * we ensure that the subsequent reads/writes will work. + */ + usleep_range(15000, 20000); + + mutex_unlock(&info->lock); +} + +static irqreturn_t ep93xx_ac97_interrupt(int irq, void *dev_id) +{ + struct ep93xx_ac97_info *info = dev_id; + unsigned status, mask; + + /* + * Just mask out the interrupt and wake up the waiting thread. + * Interrupts are cleared via reading/writing to slot 1 & 2 registers by + * the waiting thread. + */ + status = ep93xx_ac97_read_reg(info, AC97GIS); + mask = ep93xx_ac97_read_reg(info, AC97IM); + mask &= ~status; + ep93xx_ac97_write_reg(info, AC97IM, mask); + + complete(&info->done); + return IRQ_HANDLED; +} + +struct snd_ac97_bus_ops soc_ac97_ops = { + .read = ep93xx_ac97_read, + .write = ep93xx_ac97_write, + .reset = ep93xx_ac97_cold_reset, + .warm_reset = ep93xx_ac97_warm_reset, +}; +EXPORT_SYMBOL_GPL(soc_ac97_ops); + +static int ep93xx_ac97_trigger(struct snd_pcm_substream *substream, + int cmd, struct snd_soc_dai *dai) +{ + struct ep93xx_ac97_info *info = snd_soc_dai_get_drvdata(dai); + unsigned v = 0; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { + /* + * Enable compact mode, TX slots 3 & 4, and the TX FIFO + * itself. + */ + v |= AC97TXCR_CM; + v |= AC97TXCR_TX3 | AC97TXCR_TX4; + v |= AC97TXCR_TEN; + ep93xx_ac97_write_reg(info, AC97TXCR(1), v); + } else { + /* + * Enable compact mode, RX slots 3 & 4, and the RX FIFO + * itself. + */ + v |= AC97RXCR_CM; + v |= AC97RXCR_RX3 | AC97RXCR_RX4; + v |= AC97RXCR_REN; + ep93xx_ac97_write_reg(info, AC97RXCR(1), v); + } + break; + + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { + /* + * As per Cirrus EP93xx errata described below: + * + * http://www.cirrus.com/en/pubs/errata/ER667E2B.pdf + * + * we will wait for the TX FIFO to be empty before + * clearing the TEN bit. + */ + unsigned long timeout = jiffies + AC97_TIMEOUT; + + do { + v = ep93xx_ac97_read_reg(info, AC97SR(1)); + if (time_after(jiffies, timeout)) { + dev_warn(info->dev, "TX timeout\n"); + break; + } + } while (!(v & (AC97SR_TXFE | AC97SR_TXUE))); + + /* disable the TX FIFO */ + ep93xx_ac97_write_reg(info, AC97TXCR(1), 0); + } else { + /* disable the RX FIFO */ + ep93xx_ac97_write_reg(info, AC97RXCR(1), 0); + } + break; + + default: + dev_warn(info->dev, "unknown command %d\n", cmd); + return -EINVAL; + } + + return 0; +} + +static int ep93xx_ac97_startup(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct ep93xx_pcm_dma_params *dma_data; + + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + dma_data = &ep93xx_ac97_pcm_out; + else + dma_data = &ep93xx_ac97_pcm_in; + + snd_soc_dai_set_dma_data(dai, substream, dma_data); + return 0; +} + +static const struct snd_soc_dai_ops ep93xx_ac97_dai_ops = { + .startup = ep93xx_ac97_startup, + .trigger = ep93xx_ac97_trigger, +}; + +static struct snd_soc_dai_driver ep93xx_ac97_dai = { + .name = "ep93xx-ac97", + .id = 0, + .ac97_control = 1, + .playback = { + .stream_name = "AC97 Playback", + .channels_min = 2, + .channels_max = 2, + .rates = SNDRV_PCM_RATE_8000_48000, + .formats = SNDRV_PCM_FMTBIT_S16_LE, + }, + .capture = { + .stream_name = "AC97 Capture", + .channels_min = 2, + .channels_max = 2, + .rates = SNDRV_PCM_RATE_8000_48000, + .formats = SNDRV_PCM_FMTBIT_S16_LE, + }, + .ops = &ep93xx_ac97_dai_ops, +}; + +static int __devinit ep93xx_ac97_probe(struct platform_device *pdev) +{ + struct ep93xx_ac97_info *info; + struct resource *res; + unsigned int irq; + int ret; + + info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + info->regs = devm_request_and_ioremap(&pdev->dev, res); + if (!info->regs) + return -ENXIO; + + irq = platform_get_irq(pdev, 0); + if (!irq) + return -ENODEV; + + ret = devm_request_irq(&pdev->dev, irq, ep93xx_ac97_interrupt, + IRQF_TRIGGER_HIGH, pdev->name, info); + if (ret) + goto fail; + + dev_set_drvdata(&pdev->dev, info); + + mutex_init(&info->lock); + init_completion(&info->done); + info->dev = &pdev->dev; + + ep93xx_ac97_info = info; + platform_set_drvdata(pdev, info); + + ret = snd_soc_register_dai(&pdev->dev, &ep93xx_ac97_dai); + if (ret) + goto fail; + + return 0; + +fail: + platform_set_drvdata(pdev, NULL); + ep93xx_ac97_info = NULL; + dev_set_drvdata(&pdev->dev, NULL); + return ret; +} + +static int __devexit ep93xx_ac97_remove(struct platform_device *pdev) +{ + struct ep93xx_ac97_info *info = platform_get_drvdata(pdev); + + snd_soc_unregister_dai(&pdev->dev); + + /* disable the AC97 controller */ + ep93xx_ac97_write_reg(info, AC97GCR, 0); + + platform_set_drvdata(pdev, NULL); + ep93xx_ac97_info = NULL; + dev_set_drvdata(&pdev->dev, NULL); + + return 0; +} + +static struct platform_driver ep93xx_ac97_driver = { + .probe = ep93xx_ac97_probe, + .remove = __devexit_p(ep93xx_ac97_remove), + .driver = { + .name = "ep93xx-ac97", + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(ep93xx_ac97_driver); + +MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver"); +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ep93xx-ac97"); |