ASoC: ep93xx i2s audio driver

Add ep93xx i2s audio driver

Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 487 insertions, 0 deletions

diff --git a/sound/soc/ep93xx/ep93xx-i2s.c b/sound/soc/ep93xx/ep93xx-i2s.c
new file mode 100644
index 000000000000..00b946632184
--- /dev/null
+++ b/sound/soc/ep93xx/ep93xx-i2s.c
@@ -0,0 +1,487 @@
+/*
+ * linux/sound/soc/ep93xx-i2s.c
+ * EP93xx I2S driver
+ *
+ * Copyright (C) 2010 Ryan Mallon <ryan@bluewatersys.com>
+ *
+ * Based on the original driver by:
+ *   Copyright (C) 2007 Chase Douglas <chasedouglas@gmail>
+ *   Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+
+#include <mach/hardware.h>
+#include <mach/ep93xx-regs.h>
+#include <mach/dma.h>
+
+#include "ep93xx-pcm.h"
+#include "ep93xx-i2s.h"
+
+#define EP93XX_I2S_TXCLKCFG             0x00
+#define EP93XX_I2S_RXCLKCFG             0x04
+#define EP93XX_I2S_GLCTRL               0x0C
+
+#define EP93XX_I2S_TXLINCTRLDATA        0x28
+#define EP93XX_I2S_TXCTRL               0x2C
+#define EP93XX_I2S_TXWRDLEN             0x30
+#define EP93XX_I2S_TX0EN                0x34
+
+#define EP93XX_I2S_RXLINCTRLDATA        0x58
+#define EP93XX_I2S_RXCTRL               0x5C
+#define EP93XX_I2S_RXWRDLEN             0x60
+#define EP93XX_I2S_RX0EN                0x64
+
+#define EP93XX_I2S_WRDLEN_16            (0 << 0)
+#define EP93XX_I2S_WRDLEN_24            (1 << 0)
+#define EP93XX_I2S_WRDLEN_32            (2 << 0)
+
+#define EP93XX_I2S_LINCTRLDATA_R_JUST   (1 << 2) /* Right justify */
+
+#define EP93XX_I2S_CLKCFG_LRS           (1 << 0) /* lrclk polarity */
+#define EP93XX_I2S_CLKCFG_CKP           (1 << 1) /* Bit clock polarity */
+#define EP93XX_I2S_CLKCFG_REL           (1 << 2) /* First bit transition */
+#define EP93XX_I2S_CLKCFG_MASTER        (1 << 3) /* Master mode */
+#define EP93XX_I2S_CLKCFG_NBCG          (1 << 4) /* Not bit clock gating */
+
+struct ep93xx_i2s_info {
+        struct clk                      *mclk;
+        struct clk                      *sclk;
+        struct clk                      *lrclk;
+        struct ep93xx_pcm_dma_params    *dma_params;
+        struct resource                 *mem;
+        void __iomem                    *regs;
+};
+
+struct ep93xx_pcm_dma_params ep93xx_i2s_dma_params[] = {
+        [SNDRV_PCM_STREAM_PLAYBACK] = {
+                .name           = "i2s-pcm-out",
+                .dma_port       = EP93XX_DMA_M2P_PORT_I2S1,
+        },
+        [SNDRV_PCM_STREAM_CAPTURE] = {
+                .name           = "i2s-pcm-in",
+                .dma_port       = EP93XX_DMA_M2P_PORT_I2S1,
+        },
+};
+
+static inline void ep93xx_i2s_write_reg(struct ep93xx_i2s_info *info,
+                                        unsigned reg, unsigned val)
+{
+        __raw_writel(val, info->regs + reg);
+}
+
+static inline unsigned ep93xx_i2s_read_reg(struct ep93xx_i2s_info *info,
+                                           unsigned reg)
+{
+        return __raw_readl(info->regs + reg);
+}
+
+static void ep93xx_i2s_enable(struct ep93xx_i2s_info *info, int stream)
+{
+        unsigned base_reg;
+        int i;
+
+        if ((ep93xx_i2s_read_reg(info, EP93XX_I2S_TX0EN) & 0x1) == 0 &&
+            (ep93xx_i2s_read_reg(info, EP93XX_I2S_RX0EN) & 0x1) == 0) {
+                /* Enable clocks */
+                clk_enable(info->mclk);
+                clk_enable(info->sclk);
+                clk_enable(info->lrclk);
+
+                /* Enable i2s */
+                ep93xx_i2s_write_reg(info, EP93XX_I2S_GLCTRL, 1);
+        }
+
+        /* Enable fifos */
+        if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+                base_reg = EP93XX_I2S_TX0EN;
+        else
+                base_reg = EP93XX_I2S_RX0EN;
+        for (i = 0; i < 3; i++)
+                ep93xx_i2s_write_reg(info, base_reg + (i * 4), 1);
+}
+
+static void ep93xx_i2s_disable(struct ep93xx_i2s_info *info, int stream)
+{
+        unsigned base_reg;
+        int i;
+
+        /* Disable fifos */
+        if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+                base_reg = EP93XX_I2S_TX0EN;
+        else
+                base_reg = EP93XX_I2S_RX0EN;
+        for (i = 0; i < 3; i++)
+                ep93xx_i2s_write_reg(info, base_reg + (i * 4), 0);
+
+        if ((ep93xx_i2s_read_reg(info, EP93XX_I2S_TX0EN) & 0x1) == 0 &&
+            (ep93xx_i2s_read_reg(info, EP93XX_I2S_RX0EN) & 0x1) == 0) {
+                /* Disable i2s */
+                ep93xx_i2s_write_reg(info, EP93XX_I2S_GLCTRL, 0);
+
+                /* Disable clocks */
+                clk_disable(info->lrclk);
+                clk_disable(info->sclk);
+                clk_disable(info->mclk);
+        }
+}
+
+static int ep93xx_i2s_startup(struct snd_pcm_substream *substream,
+                              struct snd_soc_dai *dai)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct snd_soc_dai *cpu_dai = rtd->dai->cpu_dai;
+        struct ep93xx_i2s_info *info = rtd->dai->cpu_dai->private_data;
+
+        snd_soc_dai_set_dma_data(cpu_dai, substream,
+                                 &info->dma_params[substream->stream]);
+        return 0;
+}
+
+static void ep93xx_i2s_shutdown(struct snd_pcm_substream *substream,
+                                struct snd_soc_dai *dai)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct ep93xx_i2s_info *info = rtd->dai->cpu_dai->private_data;
+
+        ep93xx_i2s_disable(info, substream->stream);
+}
+
+static int ep93xx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
+                                  unsigned int fmt)
+{
+        struct ep93xx_i2s_info *info = cpu_dai->private_data;
+        unsigned int clk_cfg, lin_ctrl;
+
+        clk_cfg  = ep93xx_i2s_read_reg(info, EP93XX_I2S_RXCLKCFG);
+        lin_ctrl = ep93xx_i2s_read_reg(info, EP93XX_I2S_RXLINCTRLDATA);
+
+        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+        case SND_SOC_DAIFMT_I2S:
+                clk_cfg |= EP93XX_I2S_CLKCFG_REL;
+                lin_ctrl &= ~EP93XX_I2S_LINCTRLDATA_R_JUST;
+                break;
+
+        case SND_SOC_DAIFMT_LEFT_J:
+                clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
+                lin_ctrl &= ~EP93XX_I2S_LINCTRLDATA_R_JUST;
+                break;
+
+        case SND_SOC_DAIFMT_RIGHT_J:
+                clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
+                lin_ctrl |= EP93XX_I2S_LINCTRLDATA_R_JUST;
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+        case SND_SOC_DAIFMT_CBS_CFS:
+                /* CPU is master */
+                clk_cfg |= EP93XX_I2S_CLKCFG_MASTER;
+                break;
+
+        case SND_SOC_DAIFMT_CBM_CFM:
+                /* Codec is master */
+                clk_cfg &= ~EP93XX_I2S_CLKCFG_MASTER;
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+        case SND_SOC_DAIFMT_NB_NF:
+                /* Negative bit clock, lrclk low on left word */
+                clk_cfg &= ~(EP93XX_I2S_CLKCFG_CKP | EP93XX_I2S_CLKCFG_REL);
+                break;
+
+        case SND_SOC_DAIFMT_NB_IF:
+                /* Negative bit clock, lrclk low on right word */
+                clk_cfg &= ~EP93XX_I2S_CLKCFG_CKP;
+                clk_cfg |= EP93XX_I2S_CLKCFG_REL;
+                break;
+
+        case SND_SOC_DAIFMT_IB_NF:
+                /* Positive bit clock, lrclk low on left word */
+                clk_cfg |= EP93XX_I2S_CLKCFG_CKP;
+                clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
+                break;
+
+        case SND_SOC_DAIFMT_IB_IF:
+                /* Positive bit clock, lrclk low on right word */
+                clk_cfg |= EP93XX_I2S_CLKCFG_CKP | EP93XX_I2S_CLKCFG_REL;
+                break;
+        }
+
+        /* Write new register values */
+        ep93xx_i2s_write_reg(info, EP93XX_I2S_RXCLKCFG, clk_cfg);
+        ep93xx_i2s_write_reg(info, EP93XX_I2S_TXCLKCFG, clk_cfg);
+        ep93xx_i2s_write_reg(info, EP93XX_I2S_RXLINCTRLDATA, lin_ctrl);
+        ep93xx_i2s_write_reg(info, EP93XX_I2S_TXLINCTRLDATA, lin_ctrl);
+        return 0;
+}
+
+static int ep93xx_i2s_hw_params(struct snd_pcm_substream *substream,
+                                struct snd_pcm_hw_params *params,
+                                struct snd_soc_dai *dai)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct snd_soc_dai *cpu_dai = rtd->dai->cpu_dai;
+        struct ep93xx_i2s_info *info = cpu_dai->private_data;
+        unsigned word_len, div, sdiv, lrdiv;
+        int found = 0, err;
+
+        switch (params_format(params)) {
+        case SNDRV_PCM_FORMAT_S16_LE:
+                word_len = EP93XX_I2S_WRDLEN_16;
+                break;
+
+        case SNDRV_PCM_FORMAT_S24_LE:
+                word_len = EP93XX_I2S_WRDLEN_24;
+                break;
+
+        case SNDRV_PCM_FORMAT_S32_LE:
+                word_len = EP93XX_I2S_WRDLEN_32;
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                ep93xx_i2s_write_reg(info, EP93XX_I2S_TXWRDLEN, word_len);
+        else
+                ep93xx_i2s_write_reg(info, EP93XX_I2S_RXWRDLEN, word_len);
+
+        /*
+         * Calculate the sdiv (bit clock) and lrdiv (left/right clock) values.
+         * If the lrclk is pulse length is larger than the word size, then the
+         * bit clock will be gated for the unused bits.
+         */
+        div = (clk_get_rate(info->mclk) / params_rate(params)) *
+                params_channels(params);
+        for (sdiv = 2; sdiv <= 4; sdiv += 2)
+                for (lrdiv = 32; lrdiv <= 128; lrdiv <<= 1)
+                        if (sdiv * lrdiv == div) {
+                                found = 1;
+                                goto out;
+                        }
+out:
+        if (!found)
+                return -EINVAL;
+
+        err = clk_set_rate(info->sclk, clk_get_rate(info->mclk) / sdiv);
+        if (err)
+                return err;
+
+        err = clk_set_rate(info->lrclk, clk_get_rate(info->sclk) / lrdiv);
+        if (err)
+                return err;
+
+        ep93xx_i2s_enable(info, substream->stream);
+        return 0;
+}
+
+static int ep93xx_i2s_set_sysclk(struct snd_soc_dai *cpu_dai, int clk_id,
+                                 unsigned int freq, int dir)
+{
+        struct ep93xx_i2s_info *info = cpu_dai->private_data;
+
+        if (dir == SND_SOC_CLOCK_IN || clk_id != 0)
+                return -EINVAL;
+
+        return clk_set_rate(info->mclk, freq);
+}
+
+#ifdef CONFIG_PM
+static int ep93xx_i2s_suspend(struct snd_soc_dai *dai)
+{
+        struct ep93xx_i2s_info *info = dai->private_data;
+
+        if (!dai->active)
+                return;
+
+        ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_PLAYBACK);
+        ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_CAPTURE);
+}
+
+static int ep93xx_i2s_resume(struct snd_soc_dai *dai)
+{
+        struct ep93xx_i2s_info *info = dai->private_data;
+
+        if (!dai->active)
+                return;
+
+        ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_PLAYBACK);
+        ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_CAPTURE);
+}
+#else
+#define ep93xx_i2s_suspend      NULL
+#define ep93xx_i2s_resume       NULL
+#endif
+
+static struct snd_soc_dai_ops ep93xx_i2s_dai_ops = {
+        .startup        = ep93xx_i2s_startup,
+        .shutdown       = ep93xx_i2s_shutdown,
+        .hw_params      = ep93xx_i2s_hw_params,
+        .set_sysclk     = ep93xx_i2s_set_sysclk,
+        .set_fmt        = ep93xx_i2s_set_dai_fmt,
+};
+
+#define EP93XX_I2S_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
+                            SNDRV_PCM_FMTBIT_S24_LE | \
+                            SNDRV_PCM_FMTBIT_S32_LE)
+
+struct snd_soc_dai ep93xx_i2s_dai = {
+        .name           = "ep93xx-i2s",
+        .id             = 0,
+        .symmetric_rates= 1,
+        .suspend        = ep93xx_i2s_suspend,
+        .resume         = ep93xx_i2s_resume,
+        .playback       = {
+                .channels_min   = 2,
+                .channels_max   = 2,
+                .rates          = SNDRV_PCM_RATE_8000_48000,
+                .formats        = EP93XX_I2S_FORMATS,
+        },
+        .capture        = {
+                 .channels_min  = 2,
+                 .channels_max  = 2,
+                 .rates         = SNDRV_PCM_RATE_8000_48000,
+                 .formats       = EP93XX_I2S_FORMATS,
+        },
+        .ops            = &ep93xx_i2s_dai_ops,
+};
+EXPORT_SYMBOL_GPL(ep93xx_i2s_dai);
+
+static int ep93xx_i2s_probe(struct platform_device *pdev)
+{
+        struct ep93xx_i2s_info *info;
+        struct resource *res;
+        int err;
+
+        info = kzalloc(sizeof(struct ep93xx_i2s_info), GFP_KERNEL);
+        if (!info) {
+                err = -ENOMEM;
+                goto fail;
+        }
+
+        ep93xx_i2s_dai.dev = &pdev->dev;
+        ep93xx_i2s_dai.private_data = info;
+        info->dma_params = ep93xx_i2s_dma_params;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                err = -ENODEV;
+                goto fail;
+        }
+
+        info->mem = request_mem_region(res->start, resource_size(res),
+                                       pdev->name);
+        if (!info->mem) {
+                err = -EBUSY;
+                goto fail;
+        }
+
+        info->regs = ioremap(info->mem->start, resource_size(info->mem));
+        if (!info->regs) {
+                err = -ENXIO;
+                goto fail_release_mem;
+        }
+
+        info->mclk = clk_get(&pdev->dev, "mclk");
+        if (IS_ERR(info->mclk)) {
+                err = PTR_ERR(info->mclk);
+                goto fail_unmap_mem;
+        }
+
+        info->sclk = clk_get(&pdev->dev, "sclk");
+        if (IS_ERR(info->sclk)) {
+                err = PTR_ERR(info->sclk);
+                goto fail_put_mclk;
+        }
+
+        info->lrclk = clk_get(&pdev->dev, "lrclk");
+        if (IS_ERR(info->lrclk)) {
+                err = PTR_ERR(info->lrclk);
+                goto fail_put_sclk;
+        }
+
+        err = snd_soc_register_dai(&ep93xx_i2s_dai);
+        if (err)
+                goto fail_put_lrclk;
+
+        return 0;
+
+fail_put_lrclk:
+        clk_put(info->lrclk);
+fail_put_sclk:
+        clk_put(info->sclk);
+fail_put_mclk:
+        clk_put(info->mclk);
+fail_unmap_mem:
+        iounmap(info->regs);
+fail_release_mem:
+        release_mem_region(info->mem->start, resource_size(info->mem));
+        kfree(info);
+fail:
+        return err;
+}
+
+static int __devexit ep93xx_i2s_remove(struct platform_device *pdev)
+{
+        struct ep93xx_i2s_info *info = ep93xx_i2s_dai.private_data;
+
+        snd_soc_unregister_dai(&ep93xx_i2s_dai);
+        clk_put(info->lrclk);
+        clk_put(info->sclk);
+        clk_put(info->mclk);
+        iounmap(info->regs);
+        release_mem_region(info->mem->start, resource_size(info->mem));
+        kfree(info);
+        return 0;
+}
+
+static struct platform_driver ep93xx_i2s_driver = {
+        .probe  = ep93xx_i2s_probe,
+        .remove = __devexit_p(ep93xx_i2s_remove),
+        .driver = {
+                .name   = "ep93xx-i2s",
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init ep93xx_i2s_init(void)
+{
+        return platform_driver_register(&ep93xx_i2s_driver);
+}
+
+static void __exit ep93xx_i2s_exit(void)
+{
+        platform_driver_unregister(&ep93xx_i2s_driver);
+}
+
+module_init(ep93xx_i2s_init);
+module_exit(ep93xx_i2s_exit);
+
+MODULE_ALIAS("platform:ep93xx-i2s");
+MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com>");
+MODULE_DESCRIPTION("EP93XX I2S driver");
+MODULE_LICENSE("GPL");