| /* |
| * Copyright (C) 2012-2013, Analog Devices Inc. |
| * Author: Lars-Peter Clausen <lars@metafoo.de> |
| * |
| * Licensed under the GPL-2. |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include <linux/of.h> |
| #include <linux/clk.h> |
| #include <linux/regmap.h> |
| |
| #include <sound/core.h> |
| #include <sound/pcm.h> |
| #include <sound/pcm_params.h> |
| #include <sound/soc.h> |
| #include <sound/initval.h> |
| #include <sound/dmaengine_pcm.h> |
| |
| #define AXI_SPDIF_REG_CTRL 0x0 |
| #define AXI_SPDIF_REG_STAT 0x4 |
| #define AXI_SPDIF_REG_TX_FIFO 0xc |
| |
| #define AXI_SPDIF_CTRL_TXDATA BIT(1) |
| #define AXI_SPDIF_CTRL_TXEN BIT(0) |
| #define AXI_SPDIF_CTRL_CLKDIV_OFFSET 8 |
| #define AXI_SPDIF_CTRL_CLKDIV_MASK (0xff << 8) |
| |
| #define AXI_SPDIF_FREQ_44100 (0x0 << 6) |
| #define AXI_SPDIF_FREQ_48000 (0x1 << 6) |
| #define AXI_SPDIF_FREQ_32000 (0x2 << 6) |
| #define AXI_SPDIF_FREQ_NA (0x3 << 6) |
| |
| struct axi_spdif { |
| struct regmap *regmap; |
| struct clk *clk; |
| struct clk *clk_ref; |
| |
| struct snd_dmaengine_dai_dma_data dma_data; |
| |
| struct snd_ratnum ratnum; |
| struct snd_pcm_hw_constraint_ratnums rate_constraints; |
| }; |
| |
| static int axi_spdif_trigger(struct snd_pcm_substream *substream, int cmd, |
| struct snd_soc_dai *dai) |
| { |
| struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); |
| unsigned int val; |
| |
| switch (cmd) { |
| case SNDRV_PCM_TRIGGER_START: |
| case SNDRV_PCM_TRIGGER_RESUME: |
| case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: |
| val = AXI_SPDIF_CTRL_TXDATA; |
| break; |
| case SNDRV_PCM_TRIGGER_STOP: |
| case SNDRV_PCM_TRIGGER_SUSPEND: |
| case SNDRV_PCM_TRIGGER_PAUSE_PUSH: |
| val = 0; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, |
| AXI_SPDIF_CTRL_TXDATA, val); |
| |
| return 0; |
| } |
| |
| static int axi_spdif_hw_params(struct snd_pcm_substream *substream, |
| struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) |
| { |
| struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); |
| unsigned int rate = params_rate(params); |
| unsigned int clkdiv, stat; |
| |
| switch (params_rate(params)) { |
| case 32000: |
| stat = AXI_SPDIF_FREQ_32000; |
| break; |
| case 44100: |
| stat = AXI_SPDIF_FREQ_44100; |
| break; |
| case 48000: |
| stat = AXI_SPDIF_FREQ_48000; |
| break; |
| default: |
| stat = AXI_SPDIF_FREQ_NA; |
| break; |
| } |
| |
| clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(spdif->clk_ref), |
| rate * 64 * 2) - 1; |
| clkdiv <<= AXI_SPDIF_CTRL_CLKDIV_OFFSET; |
| |
| regmap_write(spdif->regmap, AXI_SPDIF_REG_STAT, stat); |
| regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, |
| AXI_SPDIF_CTRL_CLKDIV_MASK, clkdiv); |
| |
| return 0; |
| } |
| |
| static int axi_spdif_dai_probe(struct snd_soc_dai *dai) |
| { |
| struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); |
| |
| snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL); |
| |
| return 0; |
| } |
| |
| static int axi_spdif_startup(struct snd_pcm_substream *substream, |
| struct snd_soc_dai *dai) |
| { |
| struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); |
| int ret; |
| |
| ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0, |
| SNDRV_PCM_HW_PARAM_RATE, |
| &spdif->rate_constraints); |
| if (ret) |
| return ret; |
| |
| ret = clk_prepare_enable(spdif->clk_ref); |
| if (ret) |
| return ret; |
| |
| regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, |
| AXI_SPDIF_CTRL_TXEN, AXI_SPDIF_CTRL_TXEN); |
| |
| return 0; |
| } |
| |
| static void axi_spdif_shutdown(struct snd_pcm_substream *substream, |
| struct snd_soc_dai *dai) |
| { |
| struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai); |
| |
| regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL, |
| AXI_SPDIF_CTRL_TXEN, 0); |
| |
| clk_disable_unprepare(spdif->clk_ref); |
| } |
| |
| static const struct snd_soc_dai_ops axi_spdif_dai_ops = { |
| .startup = axi_spdif_startup, |
| .shutdown = axi_spdif_shutdown, |
| .trigger = axi_spdif_trigger, |
| .hw_params = axi_spdif_hw_params, |
| }; |
| |
| static struct snd_soc_dai_driver axi_spdif_dai = { |
| .probe = axi_spdif_dai_probe, |
| .playback = { |
| .channels_min = 2, |
| .channels_max = 2, |
| .rates = SNDRV_PCM_RATE_KNOT, |
| .formats = SNDRV_PCM_FMTBIT_S16_LE, |
| }, |
| .ops = &axi_spdif_dai_ops, |
| }; |
| |
| static const struct snd_soc_component_driver axi_spdif_component = { |
| .name = "axi-spdif", |
| }; |
| |
| static const struct regmap_config axi_spdif_regmap_config = { |
| .reg_bits = 32, |
| .reg_stride = 4, |
| .val_bits = 32, |
| .max_register = AXI_SPDIF_REG_STAT, |
| }; |
| |
| static int axi_spdif_probe(struct platform_device *pdev) |
| { |
| struct axi_spdif *spdif; |
| struct resource *res; |
| void __iomem *base; |
| int ret; |
| |
| spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL); |
| if (!spdif) |
| return -ENOMEM; |
| |
| platform_set_drvdata(pdev, spdif); |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| base = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(base)) |
| return PTR_ERR(base); |
| |
| spdif->regmap = devm_regmap_init_mmio(&pdev->dev, base, |
| &axi_spdif_regmap_config); |
| if (IS_ERR(spdif->regmap)) |
| return PTR_ERR(spdif->regmap); |
| |
| spdif->clk = devm_clk_get(&pdev->dev, "axi"); |
| if (IS_ERR(spdif->clk)) |
| return PTR_ERR(spdif->clk); |
| |
| spdif->clk_ref = devm_clk_get(&pdev->dev, "ref"); |
| if (IS_ERR(spdif->clk_ref)) |
| return PTR_ERR(spdif->clk_ref); |
| |
| ret = clk_prepare_enable(spdif->clk); |
| if (ret) |
| return ret; |
| |
| spdif->dma_data.addr = res->start + AXI_SPDIF_REG_TX_FIFO; |
| spdif->dma_data.addr_width = 4; |
| spdif->dma_data.maxburst = 1; |
| |
| spdif->ratnum.num = clk_get_rate(spdif->clk_ref) / 128; |
| spdif->ratnum.den_step = 1; |
| spdif->ratnum.den_min = 1; |
| spdif->ratnum.den_max = 64; |
| |
| spdif->rate_constraints.rats = &spdif->ratnum; |
| spdif->rate_constraints.nrats = 1; |
| |
| ret = devm_snd_soc_register_component(&pdev->dev, &axi_spdif_component, |
| &axi_spdif_dai, 1); |
| if (ret) |
| goto err_clk_disable; |
| |
| ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0); |
| if (ret) |
| goto err_clk_disable; |
| |
| return 0; |
| |
| err_clk_disable: |
| clk_disable_unprepare(spdif->clk); |
| return ret; |
| } |
| |
| static int axi_spdif_dev_remove(struct platform_device *pdev) |
| { |
| struct axi_spdif *spdif = platform_get_drvdata(pdev); |
| |
| clk_disable_unprepare(spdif->clk); |
| |
| return 0; |
| } |
| |
| static const struct of_device_id axi_spdif_of_match[] = { |
| { .compatible = "adi,axi-spdif-tx-1.00.a", }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, axi_spdif_of_match); |
| |
| static struct platform_driver axi_spdif_driver = { |
| .driver = { |
| .name = "axi-spdif", |
| .owner = THIS_MODULE, |
| .of_match_table = axi_spdif_of_match, |
| }, |
| .probe = axi_spdif_probe, |
| .remove = axi_spdif_dev_remove, |
| }; |
| module_platform_driver(axi_spdif_driver); |
| |
| MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
| MODULE_DESCRIPTION("AXI SPDIF driver"); |
| MODULE_LICENSE("GPL"); |