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-rw-r--r--sound/soc/cirrus/ep93xx-i2s.c519
1 files changed, 519 insertions, 0 deletions
diff --git a/sound/soc/cirrus/ep93xx-i2s.c b/sound/soc/cirrus/ep93xx-i2s.c
new file mode 100644
index 000000000..982151330
--- /dev/null
+++ b/sound/soc/cirrus/ep93xx-i2s.c
@@ -0,0 +1,519 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/sound/soc/ep93xx-i2s.c
+ * EP93xx I2S driver
+ *
+ * Copyright (C) 2010 Ryan Mallon
+ *
+ * Based on the original driver by:
+ * Copyright (C) 2007 Chase Douglas <chasedouglas@gmail>
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ */
+
+#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/dmaengine_pcm.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+
+#include <linux/platform_data/dma-ep93xx.h>
+#include <linux/soc/cirrus/ep93xx.h>
+
+#include "ep93xx-pcm.h"
+
+#define EP93XX_I2S_TXCLKCFG 0x00
+#define EP93XX_I2S_RXCLKCFG 0x04
+#define EP93XX_I2S_GLSTS 0x08
+#define EP93XX_I2S_GLCTRL 0x0C
+
+#define EP93XX_I2S_I2STX0LFT 0x10
+#define EP93XX_I2S_I2STX0RT 0x14
+
+#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_RXLINCTRLDATA_R_JUST BIT(1) /* Right justify */
+
+#define EP93XX_I2S_TXLINCTRLDATA_R_JUST BIT(2) /* Right justify */
+
+/*
+ * Transmit empty interrupt level select:
+ * 0 - Generate interrupt when FIFO is half empty
+ * 1 - Generate interrupt when FIFO is empty
+ */
+#define EP93XX_I2S_TXCTRL_TXEMPTY_LVL BIT(0)
+#define EP93XX_I2S_TXCTRL_TXUFIE BIT(1) /* Transmit interrupt enable */
+
+#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 */
+
+#define EP93XX_I2S_GLSTS_TX0_FIFO_FULL BIT(12)
+
+struct ep93xx_i2s_info {
+ struct clk *mclk;
+ struct clk *sclk;
+ struct clk *lrclk;
+ void __iomem *regs;
+ struct snd_dmaengine_dai_dma_data dma_params_rx;
+ struct snd_dmaengine_dai_dma_data dma_params_tx;
+};
+
+static struct ep93xx_dma_data ep93xx_i2s_dma_data[] = {
+ [SNDRV_PCM_STREAM_PLAYBACK] = {
+ .name = "i2s-pcm-out",
+ .port = EP93XX_DMA_I2S1,
+ .direction = DMA_MEM_TO_DEV,
+ },
+ [SNDRV_PCM_STREAM_CAPTURE] = {
+ .name = "i2s-pcm-in",
+ .port = EP93XX_DMA_I2S1,
+ .direction = DMA_DEV_TO_MEM,
+ },
+};
+
+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;
+
+ if ((ep93xx_i2s_read_reg(info, EP93XX_I2S_TX0EN) & 0x1) == 0 &&
+ (ep93xx_i2s_read_reg(info, EP93XX_I2S_RX0EN) & 0x1) == 0) {
+ /* Enable clocks */
+ clk_prepare_enable(info->mclk);
+ clk_prepare_enable(info->sclk);
+ clk_prepare_enable(info->lrclk);
+
+ /* Enable i2s */
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_GLCTRL, 1);
+ }
+
+ /* Enable fifo */
+ if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+ base_reg = EP93XX_I2S_TX0EN;
+ else
+ base_reg = EP93XX_I2S_RX0EN;
+ ep93xx_i2s_write_reg(info, base_reg, 1);
+
+ /* Enable TX IRQs (FIFO empty or underflow) */
+ if (IS_ENABLED(CONFIG_SND_EP93XX_SOC_I2S_WATCHDOG) &&
+ stream == SNDRV_PCM_STREAM_PLAYBACK)
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_TXCTRL,
+ EP93XX_I2S_TXCTRL_TXEMPTY_LVL |
+ EP93XX_I2S_TXCTRL_TXUFIE);
+}
+
+static void ep93xx_i2s_disable(struct ep93xx_i2s_info *info, int stream)
+{
+ unsigned base_reg;
+
+ /* Disable IRQs */
+ if (IS_ENABLED(CONFIG_SND_EP93XX_SOC_I2S_WATCHDOG) &&
+ stream == SNDRV_PCM_STREAM_PLAYBACK)
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_TXCTRL, 0);
+
+ /* Disable fifo */
+ if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+ base_reg = EP93XX_I2S_TX0EN;
+ else
+ base_reg = EP93XX_I2S_RX0EN;
+ ep93xx_i2s_write_reg(info, base_reg, 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_unprepare(info->lrclk);
+ clk_disable_unprepare(info->sclk);
+ clk_disable_unprepare(info->mclk);
+ }
+}
+
+/*
+ * According to documentation I2S controller can handle underflow conditions
+ * just fine, but in reality the state machine is sometimes confused so that
+ * the whole stream is shifted by one byte. The watchdog below disables the TX
+ * FIFO, fills the buffer with zeroes and re-enables the FIFO. State machine
+ * is being reset and by filling the buffer we get some time before next
+ * underflow happens.
+ */
+static irqreturn_t ep93xx_i2s_interrupt(int irq, void *dev_id)
+{
+ struct ep93xx_i2s_info *info = dev_id;
+
+ /* Disable FIFO */
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_TX0EN, 0);
+ /*
+ * Fill TX FIFO with zeroes, this way we can defer next IRQs as much as
+ * possible and get more time for DMA to catch up. Actually there are
+ * only 8 samples in this FIFO, so even on 8kHz maximum deferral here is
+ * 1ms.
+ */
+ while (!(ep93xx_i2s_read_reg(info, EP93XX_I2S_GLSTS) &
+ EP93XX_I2S_GLSTS_TX0_FIFO_FULL)) {
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_I2STX0LFT, 0);
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_I2STX0RT, 0);
+ }
+ /* Re-enable FIFO */
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_TX0EN, 1);
+
+ return IRQ_HANDLED;
+}
+
+static int ep93xx_i2s_dai_probe(struct snd_soc_dai *dai)
+{
+ struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
+
+ info->dma_params_tx.filter_data =
+ &ep93xx_i2s_dma_data[SNDRV_PCM_STREAM_PLAYBACK];
+ info->dma_params_rx.filter_data =
+ &ep93xx_i2s_dma_data[SNDRV_PCM_STREAM_CAPTURE];
+
+ dai->playback_dma_data = &info->dma_params_tx;
+ dai->capture_dma_data = &info->dma_params_rx;
+
+ return 0;
+}
+
+static void ep93xx_i2s_shutdown(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
+
+ 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 = snd_soc_dai_get_drvdata(cpu_dai);
+ unsigned int clk_cfg;
+ unsigned int txlin_ctrl = 0;
+ unsigned int rxlin_ctrl = 0;
+
+ clk_cfg = ep93xx_i2s_read_reg(info, EP93XX_I2S_RXCLKCFG);
+
+ switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ clk_cfg |= EP93XX_I2S_CLKCFG_REL;
+ break;
+
+ case SND_SOC_DAIFMT_LEFT_J:
+ clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
+ break;
+
+ case SND_SOC_DAIFMT_RIGHT_J:
+ clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
+ rxlin_ctrl |= EP93XX_I2S_RXLINCTRLDATA_R_JUST;
+ txlin_ctrl |= EP93XX_I2S_TXLINCTRLDATA_R_JUST;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
+ case SND_SOC_DAIFMT_BP_FP:
+ /* CPU is provider */
+ clk_cfg |= EP93XX_I2S_CLKCFG_MASTER;
+ break;
+
+ case SND_SOC_DAIFMT_BC_FC:
+ /* Codec is provider */
+ 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_LRS);
+ 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_LRS;
+ 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_LRS;
+ break;
+
+ case SND_SOC_DAIFMT_IB_IF:
+ /* Positive bit clock, lrclk low on right word */
+ clk_cfg |= EP93XX_I2S_CLKCFG_CKP | EP93XX_I2S_CLKCFG_LRS;
+ 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, rxlin_ctrl);
+ ep93xx_i2s_write_reg(info, EP93XX_I2S_TXLINCTRLDATA, txlin_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 ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
+ unsigned word_len, div, sdiv, lrdiv;
+ int 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);
+
+ /*
+ * EP93xx I2S module can be setup so SCLK / LRCLK value can be
+ * 32, 64, 128. MCLK / SCLK value can be 2 and 4.
+ * We set LRCLK equal to `rate' and minimum SCLK / LRCLK
+ * value is 64, because our sample size is 32 bit * 2 channels.
+ * I2S standard permits us to transmit more bits than
+ * the codec uses.
+ */
+ div = clk_get_rate(info->mclk) / params_rate(params);
+ sdiv = 4;
+ if (div > (256 + 512) / 2) {
+ lrdiv = 128;
+ } else {
+ lrdiv = 64;
+ if (div < (128 + 256) / 2)
+ sdiv = 2;
+ }
+
+ 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 = snd_soc_dai_get_drvdata(cpu_dai);
+
+ 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_component *component)
+{
+ struct ep93xx_i2s_info *info = snd_soc_component_get_drvdata(component);
+
+ if (!snd_soc_component_active(component))
+ return 0;
+
+ ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_PLAYBACK);
+ ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_CAPTURE);
+
+ return 0;
+}
+
+static int ep93xx_i2s_resume(struct snd_soc_component *component)
+{
+ struct ep93xx_i2s_info *info = snd_soc_component_get_drvdata(component);
+
+ if (!snd_soc_component_active(component))
+ return 0;
+
+ ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_PLAYBACK);
+ ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_CAPTURE);
+
+ return 0;
+}
+#else
+#define ep93xx_i2s_suspend NULL
+#define ep93xx_i2s_resume NULL
+#endif
+
+static const struct snd_soc_dai_ops ep93xx_i2s_dai_ops = {
+ .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_S32_LE)
+
+static struct snd_soc_dai_driver ep93xx_i2s_dai = {
+ .symmetric_rate = 1,
+ .probe = ep93xx_i2s_dai_probe,
+ .playback = {
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_192000,
+ .formats = EP93XX_I2S_FORMATS,
+ },
+ .capture = {
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_192000,
+ .formats = EP93XX_I2S_FORMATS,
+ },
+ .ops = &ep93xx_i2s_dai_ops,
+};
+
+static const struct snd_soc_component_driver ep93xx_i2s_component = {
+ .name = "ep93xx-i2s",
+ .suspend = ep93xx_i2s_suspend,
+ .resume = ep93xx_i2s_resume,
+ .legacy_dai_naming = 1,
+};
+
+static int ep93xx_i2s_probe(struct platform_device *pdev)
+{
+ struct ep93xx_i2s_info *info;
+ int err;
+
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ info->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(info->regs))
+ return PTR_ERR(info->regs);
+
+ if (IS_ENABLED(CONFIG_SND_EP93XX_SOC_I2S_WATCHDOG)) {
+ int irq = platform_get_irq(pdev, 0);
+ if (irq <= 0)
+ return irq < 0 ? irq : -ENODEV;
+
+ err = devm_request_irq(&pdev->dev, irq, ep93xx_i2s_interrupt, 0,
+ pdev->name, info);
+ if (err)
+ return err;
+ }
+
+ info->mclk = clk_get(&pdev->dev, "mclk");
+ if (IS_ERR(info->mclk)) {
+ err = PTR_ERR(info->mclk);
+ goto fail;
+ }
+
+ 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;
+ }
+
+ dev_set_drvdata(&pdev->dev, info);
+
+ err = devm_snd_soc_register_component(&pdev->dev, &ep93xx_i2s_component,
+ &ep93xx_i2s_dai, 1);
+ if (err)
+ goto fail_put_lrclk;
+
+ err = devm_ep93xx_pcm_platform_register(&pdev->dev);
+ 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:
+ return err;
+}
+
+static int ep93xx_i2s_remove(struct platform_device *pdev)
+{
+ struct ep93xx_i2s_info *info = dev_get_drvdata(&pdev->dev);
+
+ clk_put(info->lrclk);
+ clk_put(info->sclk);
+ clk_put(info->mclk);
+ return 0;
+}
+
+static struct platform_driver ep93xx_i2s_driver = {
+ .probe = ep93xx_i2s_probe,
+ .remove = ep93xx_i2s_remove,
+ .driver = {
+ .name = "ep93xx-i2s",
+ },
+};
+
+module_platform_driver(ep93xx_i2s_driver);
+
+MODULE_ALIAS("platform:ep93xx-i2s");
+MODULE_AUTHOR("Ryan Mallon");
+MODULE_DESCRIPTION("EP93XX I2S driver");
+MODULE_LICENSE("GPL");