CHROMIUM: ASoC: tegra: Implement SPDIF CPU DAI

sound/soc/tegra/tegra_spdif.c

+/*
+ * tegra_spdif.c - Tegra SPDIF driver
+ *
+ * Author: Stephen Warren <swarren@nvidia.com>
+ * Copyright (C) 2011 - NVIDIA, Inc.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <mach/iomap.h>
+#include <mach/dc.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include "tegra_spdif.h"
+
+#define DRV_NAME "tegra-spdif"
+
+static inline void tegra_spdif_write(struct tegra_spdif *spdif, u32 reg,
+                                        u32 val)
+{
+        __raw_writel(val, spdif->regs + reg);
+}
+
+static inline u32 tegra_spdif_read(struct tegra_spdif *spdif, u32 reg)
+{
+        return __raw_readl(spdif->regs + reg);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int tegra_spdif_show(struct seq_file *s, void *unused)
+{
+#define REG(r) { r, #r }
+        static const struct {
+                int offset;
+                const char *name;
+        } regs[] = {
+                REG(TEGRA_SPDIF_CTRL),
+                REG(TEGRA_SPDIF_STATUS),
+                REG(TEGRA_SPDIF_STROBE_CTRL),
+                REG(TEGRA_SPDIF_DATA_FIFO_CSR),
+                REG(TEGRA_SPDIF_CH_STA_RX_A),
+                REG(TEGRA_SPDIF_CH_STA_RX_B),
+                REG(TEGRA_SPDIF_CH_STA_RX_C),
+                REG(TEGRA_SPDIF_CH_STA_RX_D),
+                REG(TEGRA_SPDIF_CH_STA_RX_E),
+                REG(TEGRA_SPDIF_CH_STA_RX_F),
+                REG(TEGRA_SPDIF_CH_STA_TX_A),
+                REG(TEGRA_SPDIF_CH_STA_TX_B),
+                REG(TEGRA_SPDIF_CH_STA_TX_C),
+                REG(TEGRA_SPDIF_CH_STA_TX_D),
+                REG(TEGRA_SPDIF_CH_STA_TX_E),
+                REG(TEGRA_SPDIF_CH_STA_TX_F),
+        };
+#undef REG
+
+        struct tegra_spdif *spdif = s->private;
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(regs); i++) {
+                u32 val = tegra_spdif_read(spdif, regs[i].offset);
+                seq_printf(s, "%s = %08x\n", regs[i].name, val);
+        }
+
+        return 0;
+}
+
+static int tegra_spdif_debug_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, tegra_spdif_show, inode->i_private);
+}
+
+static const struct file_operations tegra_spdif_debug_fops = {
+        .open    = tegra_spdif_debug_open,
+        .read    = seq_read,
+        .llseek  = seq_lseek,
+        .release = single_release,
+};
+
+static void tegra_spdif_debug_add(struct tegra_spdif *spdif, int id)
+{
+        spdif->debug = debugfs_create_file(DRV_NAME, S_IRUGO,
+                                                snd_soc_debugfs_root, spdif,
+                                                &tegra_spdif_debug_fops);
+}
+
+static void tegra_spdif_debug_remove(struct tegra_spdif *spdif)
+{
+        if (spdif->debug)
+                debugfs_remove(spdif->debug);
+}
+#else
+static inline void tegra_spdif_debug_add(struct tegra_spdif *spdif)
+{
+}
+
+static inline void tegra_spdif_debug_remove(struct tegra_spdif *spdif)
+{
+}
+#endif
+
+static int tegra_spdif_hw_params(struct snd_pcm_substream *substream,
+                                struct snd_pcm_hw_params *params,
+                                struct snd_soc_dai *dai)
+{
+        struct device *dev = substream->pcm->card->dev;
+        struct tegra_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+        int ret, srate, spdifclock;
+
+        spdif->reg_ctrl &= ~TEGRA_SPDIF_CTRL_PACK;
+        spdif->reg_ctrl &= ~TEGRA_SPDIF_CTRL_BIT_MODE_MASK;
+        switch (params_format(params)) {
+        case SNDRV_PCM_FORMAT_S16_LE:
+                spdif->reg_ctrl |= TEGRA_SPDIF_CTRL_PACK;
+                spdif->reg_ctrl |= TEGRA_SPDIF_CTRL_BIT_MODE_16BIT;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        srate = params_rate(params);
+        switch (params_rate(params)) {
+        case 32000:
+                spdifclock = 4096000;
+                break;
+        case 44100:
+                spdifclock = 5644800;
+                break;
+        case 48000:
+                spdifclock = 6144000;
+                break;
+        case 88200:
+                spdifclock = 11289600;
+                break;
+        case 96000:
+                spdifclock = 12288000;
+                break;
+        case 176400:
+                spdifclock = 22579200;
+                break;
+        case 192000:
+                spdifclock = 24576000;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        ret = clk_set_rate(spdif->clk_spdif_out, spdifclock);
+        if (ret) {
+                dev_err(dev, "Can't set SPDIF clock rate: %d\n", ret);
+                return ret;
+        }
+
+        /* FIXME: Should this be in a codec driver? */
+        ret = tegra_dc_hdmi_set_audio_sample_rate(srate);
+        if (ret) {
+                dev_err(dev, "Can't configure HDMI controller: %d\n", ret);
+                return ret;
+        }
+
+        return 0;
+}
+
+static void tegra_spdif_start_playback(struct tegra_spdif *spdif)
+{
+        spdif->reg_ctrl |= TEGRA_SPDIF_CTRL_TX_EN;
+        tegra_spdif_write(spdif, TEGRA_SPDIF_CTRL, spdif->reg_ctrl);
+}
+
+static void tegra_spdif_stop_playback(struct tegra_spdif *spdif)
+{
+        spdif->reg_ctrl &= ~TEGRA_SPDIF_CTRL_TX_EN;
+        tegra_spdif_write(spdif, TEGRA_SPDIF_CTRL, spdif->reg_ctrl);
+}
+
+static int tegra_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+                                struct snd_soc_dai *dai)
+{
+        struct tegra_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+
+        switch (cmd) {
+        case SNDRV_PCM_TRIGGER_START:
+        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+        case SNDRV_PCM_TRIGGER_RESUME:
+                if (!spdif->clk_refs)
+                        clk_enable(spdif->clk_spdif_out);
+                spdif->clk_refs++;
+                tegra_spdif_start_playback(spdif);
+                break;
+        case SNDRV_PCM_TRIGGER_STOP:
+        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+        case SNDRV_PCM_TRIGGER_SUSPEND:
+                tegra_spdif_stop_playback(spdif);
+                spdif->clk_refs--;
+                if (!spdif->clk_refs)
+                        clk_disable(spdif->clk_spdif_out);
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static int tegra_spdif_probe(struct snd_soc_dai *dai)
+{
+        struct tegra_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+
+        dai->capture_dma_data = NULL;
+        dai->playback_dma_data = &spdif->playback_dma_data;
+
+        return 0;
+}
+
+static struct snd_soc_dai_ops tegra_spdif_dai_ops = {
+        .hw_params      = tegra_spdif_hw_params,
+        .trigger        = tegra_spdif_trigger,
+};
+
+struct snd_soc_dai_driver tegra_spdif_dai = {
+        .name = DRV_NAME ".0",
+        .probe = tegra_spdif_probe,
+        .playback = {
+                .channels_min = 2,
+                .channels_max = 2,
+                .rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
+                                SNDRV_PCM_RATE_48000,
+                .formats = SNDRV_PCM_FMTBIT_S16_LE,
+        },
+        .ops = &tegra_spdif_dai_ops,
+};
+
+static __devinit int tegra_spdif_platform_probe(struct platform_device *pdev)
+{
+        struct tegra_spdif *spdif;
+        struct resource *mem, *memregion, *dmareq;
+        int ret;
+
+        spdif = kzalloc(sizeof(struct tegra_spdif), GFP_KERNEL);
+        if (!spdif) {
+                dev_err(&pdev->dev, "Can't allocate tegra_spdif\n");
+                ret = -ENOMEM;
+                goto exit;
+        }
+        dev_set_drvdata(&pdev->dev, spdif);
+
+        spdif->clk_spdif_out = clk_get_sys("spdif_out", NULL);
+        if (IS_ERR(spdif->clk_spdif_out)) {
+                pr_err("Can't retrieve spdif clock\n");
+                ret = PTR_ERR(spdif->clk_spdif_out);
+                goto err_free;
+        }
+
+        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!mem) {
+                dev_err(&pdev->dev, "No memory resource\n");
+                ret = -ENODEV;
+                goto err_clk_put;
+        }
+
+        dmareq = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+        if (!dmareq) {
+                dev_err(&pdev->dev, "No DMA resource\n");
+                ret = -ENODEV;
+                goto err_clk_put;
+        }
+
+        memregion = request_mem_region(mem->start, resource_size(mem),
+                                        DRV_NAME);
+        if (!memregion) {
+                dev_err(&pdev->dev, "Memory region already claimed\n");
+                ret = -EBUSY;
+                goto err_clk_put;
+        }
+
+        spdif->regs = ioremap(mem->start, resource_size(mem));
+        if (!spdif->regs) {
+                dev_err(&pdev->dev, "ioremap failed\n");
+                ret = -ENOMEM;
+                goto err_release;
+        }
+
+        spdif->playback_dma_data.addr = mem->start + TEGRA_SPDIF_DATA_OUT;
+        spdif->playback_dma_data.wrap = 4;
+        spdif->playback_dma_data.width = 32;
+        spdif->playback_dma_data.req_sel = dmareq->start;
+
+        ret = snd_soc_register_dai(&pdev->dev, &tegra_spdif_dai);
+        if (ret) {
+                dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
+                ret = -ENOMEM;
+                goto err_unmap;
+        }
+
+        tegra_spdif_debug_add(spdif, pdev->id);
+
+        return 0;
+
+err_unmap:
+        iounmap(spdif->regs);
+err_release:
+        release_mem_region(mem->start, resource_size(mem));
+err_clk_put:
+        clk_put(spdif->clk_spdif_out);
+err_free:
+        kfree(spdif);
+exit:
+        return ret;
+}
+
+static int __devexit tegra_spdif_platform_remove(struct platform_device *pdev)
+{
+        struct tegra_spdif *spdif = dev_get_drvdata(&pdev->dev);
+        struct resource *res;
+
+        snd_soc_unregister_dai(&pdev->dev);
+
+        tegra_spdif_debug_remove(spdif);
+
+        iounmap(spdif->regs);
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        release_mem_region(res->start, resource_size(res));
+
+        clk_put(spdif->clk_spdif_out);
+
+        kfree(spdif);
+
+        return 0;
+}
+
+static struct platform_driver tegra_spdif_driver = {
+        .driver = {
+                .name = DRV_NAME,
+                .owner = THIS_MODULE,
+        },
+        .probe = tegra_spdif_platform_probe,
+        .remove = __devexit_p(tegra_spdif_platform_remove),
+};
+
+static int __init snd_tegra_spdif_init(void)
+{
+        return platform_driver_register(&tegra_spdif_driver);
+}
+module_init(snd_tegra_spdif_init);
+
+static void __exit snd_tegra_spdif_exit(void)
+{
+        platform_driver_unregister(&tegra_spdif_driver);
+}
+module_exit(snd_tegra_spdif_exit);
+
+MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
+MODULE_DESCRIPTION("Tegra SPDIF ASoC driver");
+MODULE_LICENSE("GPL");