ASoC: tegra: add ac97 host driver

This adds the driver for the Tegra 2x AC97 host controller.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 480 insertions, 0 deletions

diff --git a/sound/soc/tegra/tegra20_ac97.c b/sound/soc/tegra/tegra20_ac97.c
new file mode 100644
index 000000000000..1bae73bf1c8a
--- /dev/null
+++ b/sound/soc/tegra/tegra20_ac97.c
@@ -0,0 +1,480 @@
+/*
+ * tegra20_ac97.c - Tegra20 AC97 platform driver
+ *
+ * Copyright (c) 2012 Lucas Stach <dev@lynxeye.de>
+ *
+ * Partly based on code copyright/by:
+ *
+ * Copyright (c) 2011,2012 Toradex 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include "tegra_asoc_utils.h"
+#include "tegra20_ac97.h"
+
+#define DRV_NAME "tegra20-ac97"
+
+static struct tegra20_ac97 *workdata;
+
+static void tegra20_ac97_codec_reset(struct snd_ac97 *ac97)
+{
+        u32 readback;
+        unsigned long timeout;
+
+        /* reset line is not driven by DAC pad group, have to toggle GPIO */
+        gpio_set_value(workdata->reset_gpio, 0);
+        udelay(2);
+
+        gpio_set_value(workdata->reset_gpio, 1);
+        udelay(2);
+
+        timeout = jiffies + msecs_to_jiffies(100);
+
+        do {
+                regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
+                if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
+                        break;
+                usleep_range(1000, 2000);
+        } while (!time_after(jiffies, timeout));
+}
+
+static void tegra20_ac97_codec_warm_reset(struct snd_ac97 *ac97)
+{
+        u32 readback;
+        unsigned long timeout;
+
+        /*
+         * although sync line is driven by the DAC pad group warm reset using
+         * the controller cmd is not working, have to toggle sync line
+         * manually.
+         */
+        gpio_request(workdata->sync_gpio, "codec-sync");
+
+        gpio_direction_output(workdata->sync_gpio, 1);
+
+        udelay(2);
+        gpio_set_value(workdata->sync_gpio, 0);
+        udelay(2);
+        gpio_free(workdata->sync_gpio);
+
+        timeout = jiffies + msecs_to_jiffies(100);
+
+        do {
+                regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
+                if (readback & TEGRA20_AC97_STATUS1_CODEC1_RDY)
+                        break;
+                usleep_range(1000, 2000);
+        } while (!time_after(jiffies, timeout));
+}
+
+static unsigned short tegra20_ac97_codec_read(struct snd_ac97 *ac97_snd,
+                                              unsigned short reg)
+{
+        u32 readback;
+        unsigned long timeout;
+
+        regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
+                     (((reg | 0x80) << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
+                      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
+                     TEGRA20_AC97_CMD_BUSY);
+
+        timeout = jiffies + msecs_to_jiffies(100);
+
+        do {
+                regmap_read(workdata->regmap, TEGRA20_AC97_STATUS1, &readback);
+                if (readback & TEGRA20_AC97_STATUS1_STA_VALID1)
+                        break;
+                usleep_range(1000, 2000);
+        } while (!time_after(jiffies, timeout));
+
+        return ((readback & TEGRA20_AC97_STATUS1_STA_DATA1_MASK) >>
+                TEGRA20_AC97_STATUS1_STA_DATA1_SHIFT);
+}
+
+static void tegra20_ac97_codec_write(struct snd_ac97 *ac97_snd,
+                                     unsigned short reg, unsigned short val)
+{
+        u32 readback;
+        unsigned long timeout;
+
+        regmap_write(workdata->regmap, TEGRA20_AC97_CMD,
+                     ((reg << TEGRA20_AC97_CMD_CMD_ADDR_SHIFT) &
+                      TEGRA20_AC97_CMD_CMD_ADDR_MASK) |
+                     ((val << TEGRA20_AC97_CMD_CMD_DATA_SHIFT) &
+                      TEGRA20_AC97_CMD_CMD_DATA_MASK) |
+                     TEGRA20_AC97_CMD_BUSY);
+
+        timeout = jiffies + msecs_to_jiffies(100);
+
+        do {
+                regmap_read(workdata->regmap, TEGRA20_AC97_CMD, &readback);
+                if (!(readback & TEGRA20_AC97_CMD_BUSY))
+                        break;
+                usleep_range(1000, 2000);
+        } while (!time_after(jiffies, timeout));
+}
+
+struct snd_ac97_bus_ops soc_ac97_ops = {
+        .read           = tegra20_ac97_codec_read,
+        .write          = tegra20_ac97_codec_write,
+        .reset          = tegra20_ac97_codec_reset,
+        .warm_reset     = tegra20_ac97_codec_warm_reset,
+};
+EXPORT_SYMBOL_GPL(soc_ac97_ops);
+
+static inline void tegra20_ac97_start_playback(struct tegra20_ac97 *ac97)
+{
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
+                           TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN,
+                           TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN);
+
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
+                           TEGRA20_AC97_CTRL_PCM_DAC_EN |
+                           TEGRA20_AC97_CTRL_STM_EN,
+                           TEGRA20_AC97_CTRL_PCM_DAC_EN |
+                           TEGRA20_AC97_CTRL_STM_EN);
+}
+
+static inline void tegra20_ac97_stop_playback(struct tegra20_ac97 *ac97)
+{
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
+                           TEGRA20_AC97_FIFO_SCR_PB_QRT_MT_EN, 0);
+
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_CTRL,
+                           TEGRA20_AC97_CTRL_PCM_DAC_EN, 0);
+}
+
+static inline void tegra20_ac97_start_capture(struct tegra20_ac97 *ac97)
+{
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
+                           TEGRA20_AC97_FIFO_SCR_REC_FULL_EN,
+                           TEGRA20_AC97_FIFO_SCR_REC_FULL_EN);
+}
+
+static inline void tegra20_ac97_stop_capture(struct tegra20_ac97 *ac97)
+{
+        regmap_update_bits(ac97->regmap, TEGRA20_AC97_FIFO1_SCR,
+                           TEGRA20_AC97_FIFO_SCR_REC_FULL_EN, 0);
+}
+
+static int tegra20_ac97_trigger(struct snd_pcm_substream *substream, int cmd,
+                                struct snd_soc_dai *dai)
+{
+        struct tegra20_ac97 *ac97 = 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 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                        tegra20_ac97_start_playback(ac97);
+                else
+                        tegra20_ac97_start_capture(ac97);
+                break;
+        case SNDRV_PCM_TRIGGER_STOP:
+        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+        case SNDRV_PCM_TRIGGER_SUSPEND:
+                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                        tegra20_ac97_stop_playback(ac97);
+                else
+                        tegra20_ac97_stop_capture(ac97);
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static const struct snd_soc_dai_ops tegra20_ac97_dai_ops = {
+        .trigger        = tegra20_ac97_trigger,
+};
+
+static int tegra20_ac97_probe(struct snd_soc_dai *dai)
+{
+        struct tegra20_ac97 *ac97 = snd_soc_dai_get_drvdata(dai);
+
+        dai->capture_dma_data = &ac97->capture_dma_data;
+        dai->playback_dma_data = &ac97->playback_dma_data;
+
+        return 0;
+}
+
+static struct snd_soc_dai_driver tegra20_ac97_dai = {
+        .name = "tegra-ac97-pcm",
+        .ac97_control = 1,
+        .probe = tegra20_ac97_probe,
+        .playback = {
+                .stream_name = "PCM Playback",
+                .channels_min = 2,
+                .channels_max = 2,
+                .rates = SNDRV_PCM_RATE_8000_48000,
+                .formats = SNDRV_PCM_FMTBIT_S16_LE,
+        },
+        .capture = {
+                .stream_name = "PCM Capture",
+                .channels_min = 2,
+                .channels_max = 2,
+                .rates = SNDRV_PCM_RATE_8000_48000,
+                .formats = SNDRV_PCM_FMTBIT_S16_LE,
+        },
+        .ops = &tegra20_ac97_dai_ops,
+};
+
+static bool tegra20_ac97_wr_rd_reg(struct device *dev, unsigned int reg)
+{
+        switch (reg) {
+        case TEGRA20_AC97_CTRL:
+        case TEGRA20_AC97_CMD:
+        case TEGRA20_AC97_STATUS1:
+        case TEGRA20_AC97_FIFO1_SCR:
+        case TEGRA20_AC97_FIFO_TX1:
+        case TEGRA20_AC97_FIFO_RX1:
+                return true;
+        default:
+                break;
+        }
+
+        return false;
+}
+
+static bool tegra20_ac97_volatile_reg(struct device *dev, unsigned int reg)
+{
+        switch (reg) {
+        case TEGRA20_AC97_STATUS1:
+        case TEGRA20_AC97_FIFO1_SCR:
+        case TEGRA20_AC97_FIFO_TX1:
+        case TEGRA20_AC97_FIFO_RX1:
+                return true;
+        default:
+                break;
+        }
+
+        return false;
+}
+
+static bool tegra20_ac97_precious_reg(struct device *dev, unsigned int reg)
+{
+        switch (reg) {
+        case TEGRA20_AC97_FIFO_TX1:
+        case TEGRA20_AC97_FIFO_RX1:
+                return true;
+        default:
+                break;
+        }
+
+        return false;
+}
+
+static const struct regmap_config tegra20_ac97_regmap_config = {
+        .reg_bits = 32,
+        .reg_stride = 4,
+        .val_bits = 32,
+        .max_register = TEGRA20_AC97_FIFO_RX1,
+        .writeable_reg = tegra20_ac97_wr_rd_reg,
+        .readable_reg = tegra20_ac97_wr_rd_reg,
+        .volatile_reg = tegra20_ac97_volatile_reg,
+        .precious_reg = tegra20_ac97_precious_reg,
+        .cache_type = REGCACHE_RBTREE,
+};
+
+static int tegra20_ac97_platform_probe(struct platform_device *pdev)
+{
+        struct tegra20_ac97 *ac97;
+        struct resource *mem, *memregion;
+        u32 of_dma[2];
+        void __iomem *regs;
+        int ret = 0;
+
+        ac97 = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_ac97),
+                            GFP_KERNEL);
+        if (!ac97) {
+                dev_err(&pdev->dev, "Can't allocate tegra20_ac97\n");
+                ret = -ENOMEM;
+                goto err;
+        }
+        dev_set_drvdata(&pdev->dev, ac97);
+
+        ac97->clk_ac97 = clk_get(&pdev->dev, NULL);
+        if (IS_ERR(ac97->clk_ac97)) {
+                dev_err(&pdev->dev, "Can't retrieve ac97 clock\n");
+                ret = PTR_ERR(ac97->clk_ac97);
+                goto err;
+        }
+
+        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!mem) {
+                dev_err(&pdev->dev, "No memory resource\n");
+                ret = -ENODEV;
+                goto err_clk_put;
+        }
+
+        memregion = devm_request_mem_region(&pdev->dev, mem->start,
+                                            resource_size(mem), DRV_NAME);
+        if (!memregion) {
+                dev_err(&pdev->dev, "Memory region already claimed\n");
+                ret = -EBUSY;
+                goto err_clk_put;
+        }
+
+        regs = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
+        if (!regs) {
+                dev_err(&pdev->dev, "ioremap failed\n");
+                ret = -ENOMEM;
+                goto err_clk_put;
+        }
+
+        ac97->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
+                                            &tegra20_ac97_regmap_config);
+        if (IS_ERR(ac97->regmap)) {
+                dev_err(&pdev->dev, "regmap init failed\n");
+                ret = PTR_ERR(ac97->regmap);
+                goto err_clk_put;
+        }
+
+        if (of_property_read_u32_array(pdev->dev.of_node,
+                                       "nvidia,dma-request-selector",
+                                       of_dma, 2) < 0) {
+                dev_err(&pdev->dev, "No DMA resource\n");
+                ret = -ENODEV;
+                goto err_clk_put;
+        }
+
+        ac97->reset_gpio = of_get_named_gpio(pdev->dev.of_node,
+                                             "nvidia,codec-reset-gpio", 0);
+        if (gpio_is_valid(ac97->reset_gpio)) {
+                ret = devm_gpio_request_one(&pdev->dev, ac97->reset_gpio,
+                                            GPIOF_OUT_INIT_HIGH, "codec-reset");
+                if (ret) {
+                        dev_err(&pdev->dev, "could not get codec-reset GPIO\n");
+                        goto err_clk_put;
+                }
+        } else {
+                dev_err(&pdev->dev, "no codec-reset GPIO supplied\n");
+                goto err_clk_put;
+        }
+
+        ac97->sync_gpio = of_get_named_gpio(pdev->dev.of_node,
+                                            "nvidia,codec-sync-gpio", 0);
+        if (!gpio_is_valid(ac97->sync_gpio)) {
+                dev_err(&pdev->dev, "no codec-sync GPIO supplied\n");
+                goto err_clk_put;
+        }
+
+        ac97->capture_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_RX1;
+        ac97->capture_dma_data.wrap = 4;
+        ac97->capture_dma_data.width = 32;
+        ac97->capture_dma_data.req_sel = of_dma[1];
+
+        ac97->playback_dma_data.addr = mem->start + TEGRA20_AC97_FIFO_TX1;
+        ac97->playback_dma_data.wrap = 4;
+        ac97->playback_dma_data.width = 32;
+        ac97->playback_dma_data.req_sel = of_dma[1];
+
+        ret = snd_soc_register_dais(&pdev->dev, &tegra20_ac97_dai, 1);
+        if (ret) {
+                dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
+                ret = -ENOMEM;
+                goto err_clk_put;
+        }
+
+        ret = tegra_pcm_platform_register(&pdev->dev);
+        if (ret) {
+                dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
+                goto err_unregister_dai;
+        }
+
+        ret = tegra_asoc_utils_init(&ac97->util_data, &pdev->dev);
+        if (ret)
+                goto err_unregister_pcm;
+
+        ret = tegra_asoc_utils_set_ac97_rate(&ac97->util_data);
+        if (ret)
+                goto err_asoc_utils_fini;
+
+        ret = clk_prepare_enable(ac97->clk_ac97);
+        if (ret) {
+                dev_err(&pdev->dev, "clk_enable failed: %d\n", ret);
+                goto err_asoc_utils_fini;
+        }
+
+        /* XXX: crufty ASoC AC97 API - only one AC97 codec allowed */
+        workdata = ac97;
+
+        return 0;
+
+err_asoc_utils_fini:
+        tegra_asoc_utils_fini(&ac97->util_data);
+err_unregister_pcm:
+        tegra_pcm_platform_unregister(&pdev->dev);
+err_unregister_dai:
+        snd_soc_unregister_dai(&pdev->dev);
+err_clk_put:
+        clk_put(ac97->clk_ac97);
+err:
+        return ret;
+}
+
+static int tegra20_ac97_platform_remove(struct platform_device *pdev)
+{
+        struct tegra20_ac97 *ac97 = dev_get_drvdata(&pdev->dev);
+
+        tegra_pcm_platform_unregister(&pdev->dev);
+        snd_soc_unregister_dai(&pdev->dev);
+
+        tegra_asoc_utils_fini(&ac97->util_data);
+
+        clk_disable_unprepare(ac97->clk_ac97);
+        clk_put(ac97->clk_ac97);
+
+        return 0;
+}
+
+static const struct of_device_id tegra20_ac97_of_match[] __devinitconst = {
+        { .compatible = "nvidia,tegra20-ac97", },
+        {},
+};
+
+static struct platform_driver tegra20_ac97_driver = {
+        .driver = {
+                .name = DRV_NAME,
+                .owner = THIS_MODULE,
+                .of_match_table = tegra20_ac97_of_match,
+        },
+        .probe = tegra20_ac97_platform_probe,
+        .remove = tegra20_ac97_platform_remove,
+};
+module_platform_driver(tegra20_ac97_driver);
+
+MODULE_AUTHOR("Lucas Stach");
+MODULE_DESCRIPTION("Tegra20 AC97 ASoC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DEVICE_TABLE(of, tegra20_ac97_of_match);