/* * 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 #include #include #include #include #include #include #include #include #include #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 * @mem: physical memory resource for the registers * @regs: mapped AC97 controller registers * @irq: AC97 interrupt number * @done: bus ops wait here for an interrupt */ struct ep93xx_ac97_info { struct mutex lock; struct device *dev; struct resource *mem; void __iomem *regs; int irq; 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 struct snd_soc_dai_ops ep93xx_ac97_dai_ops = { .startup = ep93xx_ac97_startup, .trigger = ep93xx_ac97_trigger, }; 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; int ret; info = kzalloc(sizeof(struct ep93xx_ac97_info), GFP_KERNEL); if (!info) return -ENOMEM; dev_set_drvdata(&pdev->dev, info); mutex_init(&info->lock); init_completion(&info->done); info->dev = &pdev->dev; info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!info->mem) { ret = -ENXIO; goto fail_free_info; } info->irq = platform_get_irq(pdev, 0); if (!info->irq) { ret = -ENXIO; goto fail_free_info; } if (!request_mem_region(info->mem->start, resource_size(info->mem), pdev->name)) { ret = -EBUSY; goto fail_free_info; } info->regs = ioremap(info->mem->start, resource_size(info->mem)); if (!info->regs) { ret = -ENOMEM; goto fail_release_mem; } ret = request_irq(info->irq, ep93xx_ac97_interrupt, IRQF_TRIGGER_HIGH, pdev->name, info); if (ret) goto fail_unmap_mem; ep93xx_ac97_info = info; platform_set_drvdata(pdev, info); ret = snd_soc_register_dai(&pdev->dev, &ep93xx_ac97_dai); if (ret) goto fail_free_irq; return 0; fail_free_irq: platform_set_drvdata(pdev, NULL); free_irq(info->irq, info); fail_unmap_mem: iounmap(info->regs); fail_release_mem: release_mem_region(info->mem->start, resource_size(info->mem)); fail_free_info: kfree(info); 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); free_irq(info->irq, info); iounmap(info->regs); release_mem_region(info->mem->start, resource_size(info->mem)); platform_set_drvdata(pdev, NULL); kfree(info); 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, }, }; static int __init ep93xx_ac97_init(void) { return platform_driver_register(&ep93xx_ac97_driver); } module_init(ep93xx_ac97_init); static void __exit ep93xx_ac97_exit(void) { platform_driver_unregister(&ep93xx_ac97_driver); } module_exit(ep93xx_ac97_exit); MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver"); MODULE_AUTHOR("Mika Westerberg "); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:ep93xx-ac97");