Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 651 insertions, 0 deletions

diff --git a/sound/soc/fsl/imx-ssi.c b/sound/soc/fsl/imx-ssi.c
new file mode 100644
index 000000000..f8488e8f5
--- /dev/null
+++ b/sound/soc/fsl/imx-ssi.c
@@ -0,0 +1,651 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// imx-ssi.c  --  ALSA Soc Audio Layer
+//
+// Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
+//
+// This code is based on code copyrighted by Freescale,
+// Liam Girdwood, Javier Martin and probably others.
+//
+// The i.MX SSI core has some nasty limitations in AC97 mode. While most
+// sane processor vendors have a FIFO per AC97 slot, the i.MX has only
+// one FIFO which combines all valid receive slots. We cannot even select
+// which slots we want to receive. The WM9712 with which this driver
+// was developed with always sends GPIO status data in slot 12 which
+// we receive in our (PCM-) data stream. The only chance we have is to
+// manually skip this data in the FIQ handler. With sampling rates different
+// from 48000Hz not every frame has valid receive data, so the ratio
+// between pcm data and GPIO status data changes. Our FIQ handler is not
+// able to handle this, hence this driver only works with 48000Hz sampling
+// rate.
+// Reading and writing AC97 registers is another challenge. The core
+// provides us status bits when the read register is updated with *another*
+// value. When we read the same register two times (and the register still
+// contains the same value) these status bits are not set. We work
+// around this by not polling these bits but only wait a fixed delay.
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <linux/platform_data/asoc-imx-ssi.h>
+
+#include "imx-ssi.h"
+#include "fsl_utils.h"
+
+#define SSI_SACNT_DEFAULT (SSI_SACNT_AC97EN | SSI_SACNT_FV)
+
+/*
+ * SSI Network Mode or TDM slots configuration.
+ * Should only be called when port is inactive (i.e. SSIEN = 0).
+ */
+static int imx_ssi_set_dai_tdm_slot(struct snd_soc_dai *cpu_dai,
+	unsigned int tx_mask, unsigned int rx_mask, int slots, int slot_width)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 sccr;
+
+	sccr = readl(ssi->base + SSI_STCCR);
+	sccr &= ~SSI_STCCR_DC_MASK;
+	sccr |= SSI_STCCR_DC(slots - 1);
+	writel(sccr, ssi->base + SSI_STCCR);
+
+	sccr = readl(ssi->base + SSI_SRCCR);
+	sccr &= ~SSI_STCCR_DC_MASK;
+	sccr |= SSI_STCCR_DC(slots - 1);
+	writel(sccr, ssi->base + SSI_SRCCR);
+
+	writel(~tx_mask, ssi->base + SSI_STMSK);
+	writel(~rx_mask, ssi->base + SSI_SRMSK);
+
+	return 0;
+}
+
+/*
+ * SSI DAI format configuration.
+ * Should only be called when port is inactive (i.e. SSIEN = 0).
+ */
+static int imx_ssi_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 strcr = 0, scr;
+
+	scr = readl(ssi->base + SSI_SCR) & ~(SSI_SCR_SYN | SSI_SCR_NET);
+
+	/* DAI mode */
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		/* data on rising edge of bclk, frame low 1clk before data */
+		strcr |= SSI_STCR_TXBIT0 | SSI_STCR_TSCKP | SSI_STCR_TFSI |
+			SSI_STCR_TEFS;
+		scr |= SSI_SCR_NET;
+		if (ssi->flags & IMX_SSI_USE_I2S_SLAVE) {
+			scr &= ~SSI_I2S_MODE_MASK;
+			scr |= SSI_SCR_I2S_MODE_SLAVE;
+		}
+		break;
+	case SND_SOC_DAIFMT_LEFT_J:
+		/* data on rising edge of bclk, frame high with data */
+		strcr |= SSI_STCR_TXBIT0 | SSI_STCR_TSCKP;
+		break;
+	case SND_SOC_DAIFMT_DSP_B:
+		/* data on rising edge of bclk, frame high with data */
+		strcr |= SSI_STCR_TXBIT0 | SSI_STCR_TSCKP | SSI_STCR_TFSL;
+		break;
+	case SND_SOC_DAIFMT_DSP_A:
+		/* data on rising edge of bclk, frame high 1clk before data */
+		strcr |= SSI_STCR_TXBIT0 | SSI_STCR_TSCKP | SSI_STCR_TFSL |
+			SSI_STCR_TEFS;
+		break;
+	}
+
+	/* DAI clock inversion */
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_IB_IF:
+		strcr ^= SSI_STCR_TSCKP | SSI_STCR_TFSI;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		strcr ^= SSI_STCR_TSCKP;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		strcr ^= SSI_STCR_TFSI;
+		break;
+	case SND_SOC_DAIFMT_NB_NF:
+		break;
+	}
+
+	/* DAI clock master masks */
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		break;
+	default:
+		/* Master mode not implemented, needs handling of clocks. */
+		return -EINVAL;
+	}
+
+	strcr |= SSI_STCR_TFEN0;
+
+	if (ssi->flags & IMX_SSI_NET)
+		scr |= SSI_SCR_NET;
+	if (ssi->flags & IMX_SSI_SYN)
+		scr |= SSI_SCR_SYN;
+
+	writel(strcr, ssi->base + SSI_STCR);
+	writel(strcr, ssi->base + SSI_SRCR);
+	writel(scr, ssi->base + SSI_SCR);
+
+	return 0;
+}
+
+/*
+ * SSI system clock configuration.
+ * Should only be called when port is inactive (i.e. SSIEN = 0).
+ */
+static int imx_ssi_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
+				  int clk_id, unsigned int freq, int dir)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 scr;
+
+	scr = readl(ssi->base + SSI_SCR);
+
+	switch (clk_id) {
+	case IMX_SSP_SYS_CLK:
+		if (dir == SND_SOC_CLOCK_OUT)
+			scr |= SSI_SCR_SYS_CLK_EN;
+		else
+			scr &= ~SSI_SCR_SYS_CLK_EN;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel(scr, ssi->base + SSI_SCR);
+
+	return 0;
+}
+
+/*
+ * SSI Clock dividers
+ * Should only be called when port is inactive (i.e. SSIEN = 0).
+ */
+static int imx_ssi_set_dai_clkdiv(struct snd_soc_dai *cpu_dai,
+				  int div_id, int div)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 stccr, srccr;
+
+	stccr = readl(ssi->base + SSI_STCCR);
+	srccr = readl(ssi->base + SSI_SRCCR);
+
+	switch (div_id) {
+	case IMX_SSI_TX_DIV_2:
+		stccr &= ~SSI_STCCR_DIV2;
+		stccr |= div;
+		break;
+	case IMX_SSI_TX_DIV_PSR:
+		stccr &= ~SSI_STCCR_PSR;
+		stccr |= div;
+		break;
+	case IMX_SSI_TX_DIV_PM:
+		stccr &= ~0xff;
+		stccr |= SSI_STCCR_PM(div);
+		break;
+	case IMX_SSI_RX_DIV_2:
+		stccr &= ~SSI_STCCR_DIV2;
+		stccr |= div;
+		break;
+	case IMX_SSI_RX_DIV_PSR:
+		stccr &= ~SSI_STCCR_PSR;
+		stccr |= div;
+		break;
+	case IMX_SSI_RX_DIV_PM:
+		stccr &= ~0xff;
+		stccr |= SSI_STCCR_PM(div);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel(stccr, ssi->base + SSI_STCCR);
+	writel(srccr, ssi->base + SSI_SRCCR);
+
+	return 0;
+}
+
+/*
+ * Should only be called when port is inactive (i.e. SSIEN = 0),
+ * although can be called multiple times by upper layers.
+ */
+static int imx_ssi_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *cpu_dai)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 reg, sccr;
+
+	/* Tx/Rx config */
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		reg = SSI_STCCR;
+	else
+		reg = SSI_SRCCR;
+
+	if (ssi->flags & IMX_SSI_SYN)
+		reg = SSI_STCCR;
+
+	sccr = readl(ssi->base + reg) & ~SSI_STCCR_WL_MASK;
+
+	/* DAI data (word) size */
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		sccr |= SSI_SRCCR_WL(16);
+		break;
+	case SNDRV_PCM_FORMAT_S20_3LE:
+		sccr |= SSI_SRCCR_WL(20);
+		break;
+	case SNDRV_PCM_FORMAT_S24_LE:
+		sccr |= SSI_SRCCR_WL(24);
+		break;
+	}
+
+	writel(sccr, ssi->base + reg);
+
+	return 0;
+}
+
+static int imx_ssi_trigger(struct snd_pcm_substream *substream, int cmd,
+		struct snd_soc_dai *dai)
+{
+	struct imx_ssi *ssi = snd_soc_dai_get_drvdata(dai);
+	unsigned int sier_bits, sier;
+	unsigned int scr;
+
+	scr = readl(ssi->base + SSI_SCR);
+	sier = readl(ssi->base + SSI_SIER);
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		if (ssi->flags & IMX_SSI_DMA)
+			sier_bits = SSI_SIER_TDMAE;
+		else
+			sier_bits = SSI_SIER_TIE | SSI_SIER_TFE0_EN;
+	} else {
+		if (ssi->flags & IMX_SSI_DMA)
+			sier_bits = SSI_SIER_RDMAE;
+		else
+			sier_bits = SSI_SIER_RIE | SSI_SIER_RFF0_EN;
+	}
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			scr |= SSI_SCR_TE;
+		else
+			scr |= SSI_SCR_RE;
+		sier |= sier_bits;
+
+		scr |= SSI_SCR_SSIEN;
+
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			scr &= ~SSI_SCR_TE;
+		else
+			scr &= ~SSI_SCR_RE;
+		sier &= ~sier_bits;
+
+		if (!(scr & (SSI_SCR_TE | SSI_SCR_RE)))
+			scr &= ~SSI_SCR_SSIEN;
+
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (!(ssi->flags & IMX_SSI_USE_AC97))
+		/* rx/tx are always enabled to access ac97 registers */
+		writel(scr, ssi->base + SSI_SCR);
+
+	writel(sier, ssi->base + SSI_SIER);
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops imx_ssi_pcm_dai_ops = {
+	.hw_params	= imx_ssi_hw_params,
+	.set_fmt	= imx_ssi_set_dai_fmt,
+	.set_clkdiv	= imx_ssi_set_dai_clkdiv,
+	.set_sysclk	= imx_ssi_set_dai_sysclk,
+	.set_tdm_slot	= imx_ssi_set_dai_tdm_slot,
+	.trigger	= imx_ssi_trigger,
+};
+
+static int imx_ssi_dai_probe(struct snd_soc_dai *dai)
+{
+	struct imx_ssi *ssi = dev_get_drvdata(dai->dev);
+	uint32_t val;
+
+	snd_soc_dai_set_drvdata(dai, ssi);
+
+	val = SSI_SFCSR_TFWM0(ssi->dma_params_tx.maxburst) |
+		SSI_SFCSR_RFWM0(ssi->dma_params_rx.maxburst);
+	writel(val, ssi->base + SSI_SFCSR);
+
+	/* Tx/Rx config */
+	dai->playback_dma_data = &ssi->dma_params_tx;
+	dai->capture_dma_data = &ssi->dma_params_rx;
+
+	return 0;
+}
+
+static struct snd_soc_dai_driver imx_ssi_dai = {
+	.probe = imx_ssi_dai_probe,
+	.playback = {
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_96000,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.capture = {
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_96000,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.ops = &imx_ssi_pcm_dai_ops,
+};
+
+static struct snd_soc_dai_driver imx_ac97_dai = {
+	.probe = imx_ssi_dai_probe,
+	.playback = {
+		.stream_name = "AC97 Playback",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_48000,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.capture = {
+		.stream_name = "AC97 Capture",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_48000,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.ops = &imx_ssi_pcm_dai_ops,
+};
+
+static const struct snd_soc_component_driver imx_component = {
+	.name		= DRV_NAME,
+};
+
+static void setup_channel_to_ac97(struct imx_ssi *imx_ssi)
+{
+	void __iomem *base = imx_ssi->base;
+
+	writel(0x0, base + SSI_SCR);
+	writel(0x0, base + SSI_STCR);
+	writel(0x0, base + SSI_SRCR);
+
+	writel(SSI_SCR_SYN | SSI_SCR_NET, base + SSI_SCR);
+
+	writel(SSI_SFCSR_RFWM0(8) |
+		SSI_SFCSR_TFWM0(8) |
+		SSI_SFCSR_RFWM1(8) |
+		SSI_SFCSR_TFWM1(8), base + SSI_SFCSR);
+
+	writel(SSI_STCCR_WL(16) | SSI_STCCR_DC(12), base + SSI_STCCR);
+	writel(SSI_STCCR_WL(16) | SSI_STCCR_DC(12), base + SSI_SRCCR);
+
+	writel(SSI_SCR_SYN | SSI_SCR_NET | SSI_SCR_SSIEN, base + SSI_SCR);
+	writel(SSI_SOR_WAIT(3), base + SSI_SOR);
+
+	writel(SSI_SCR_SYN | SSI_SCR_NET | SSI_SCR_SSIEN |
+			SSI_SCR_TE | SSI_SCR_RE,
+			base + SSI_SCR);
+
+	writel(SSI_SACNT_DEFAULT, base + SSI_SACNT);
+	writel(0xff, base + SSI_SACCDIS);
+	writel(0x300, base + SSI_SACCEN);
+}
+
+static struct imx_ssi *ac97_ssi;
+
+static void imx_ssi_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
+		unsigned short val)
+{
+	struct imx_ssi *imx_ssi = ac97_ssi;
+	void __iomem *base = imx_ssi->base;
+	unsigned int lreg;
+	unsigned int lval;
+
+	if (reg > 0x7f)
+		return;
+
+	pr_debug("%s: 0x%02x 0x%04x\n", __func__, reg, val);
+
+	lreg = reg <<  12;
+	writel(lreg, base + SSI_SACADD);
+
+	lval = val << 4;
+	writel(lval , base + SSI_SACDAT);
+
+	writel(SSI_SACNT_DEFAULT | SSI_SACNT_WR, base + SSI_SACNT);
+	udelay(100);
+}
+
+static unsigned short imx_ssi_ac97_read(struct snd_ac97 *ac97,
+		unsigned short reg)
+{
+	struct imx_ssi *imx_ssi = ac97_ssi;
+	void __iomem *base = imx_ssi->base;
+
+	unsigned short val = -1;
+	unsigned int lreg;
+
+	lreg = (reg & 0x7f) <<  12 ;
+	writel(lreg, base + SSI_SACADD);
+	writel(SSI_SACNT_DEFAULT | SSI_SACNT_RD, base + SSI_SACNT);
+
+	udelay(100);
+
+	val = (readl(base + SSI_SACDAT) >> 4) & 0xffff;
+
+	pr_debug("%s: 0x%02x 0x%04x\n", __func__, reg, val);
+
+	return val;
+}
+
+static void imx_ssi_ac97_reset(struct snd_ac97 *ac97)
+{
+	struct imx_ssi *imx_ssi = ac97_ssi;
+
+	if (imx_ssi->ac97_reset)
+		imx_ssi->ac97_reset(ac97);
+	/* First read sometimes fails, do a dummy read */
+	imx_ssi_ac97_read(ac97, 0);
+}
+
+static void imx_ssi_ac97_warm_reset(struct snd_ac97 *ac97)
+{
+	struct imx_ssi *imx_ssi = ac97_ssi;
+
+	if (imx_ssi->ac97_warm_reset)
+		imx_ssi->ac97_warm_reset(ac97);
+
+	/* First read sometimes fails, do a dummy read */
+	imx_ssi_ac97_read(ac97, 0);
+}
+
+static struct snd_ac97_bus_ops imx_ssi_ac97_ops = {
+	.read		= imx_ssi_ac97_read,
+	.write		= imx_ssi_ac97_write,
+	.reset		= imx_ssi_ac97_reset,
+	.warm_reset	= imx_ssi_ac97_warm_reset
+};
+
+static int imx_ssi_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct imx_ssi *ssi;
+	struct imx_ssi_platform_data *pdata = pdev->dev.platform_data;
+	int ret = 0;
+	struct snd_soc_dai_driver *dai;
+
+	ssi = devm_kzalloc(&pdev->dev, sizeof(*ssi), GFP_KERNEL);
+	if (!ssi)
+		return -ENOMEM;
+	dev_set_drvdata(&pdev->dev, ssi);
+
+	if (pdata) {
+		ssi->ac97_reset = pdata->ac97_reset;
+		ssi->ac97_warm_reset = pdata->ac97_warm_reset;
+		ssi->flags = pdata->flags;
+	}
+
+	ssi->irq = platform_get_irq(pdev, 0);
+	if (ssi->irq < 0)
+		return ssi->irq;
+
+	ssi->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(ssi->clk)) {
+		ret = PTR_ERR(ssi->clk);
+		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
+			ret);
+		goto failed_clk;
+	}
+	ret = clk_prepare_enable(ssi->clk);
+	if (ret)
+		goto failed_clk;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ssi->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(ssi->base)) {
+		ret = PTR_ERR(ssi->base);
+		goto failed_register;
+	}
+
+	if (ssi->flags & IMX_SSI_USE_AC97) {
+		if (ac97_ssi) {
+			dev_err(&pdev->dev, "AC'97 SSI already registered\n");
+			ret = -EBUSY;
+			goto failed_register;
+		}
+		ac97_ssi = ssi;
+		setup_channel_to_ac97(ssi);
+		dai = &imx_ac97_dai;
+	} else
+		dai = &imx_ssi_dai;
+
+	writel(0x0, ssi->base + SSI_SIER);
+
+	ssi->dma_params_rx.addr = res->start + SSI_SRX0;
+	ssi->dma_params_tx.addr = res->start + SSI_STX0;
+
+	ssi->dma_params_tx.maxburst = 6;
+	ssi->dma_params_rx.maxburst = 4;
+
+	ssi->dma_params_tx.filter_data = &ssi->filter_data_tx;
+	ssi->dma_params_rx.filter_data = &ssi->filter_data_rx;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx0");
+	if (res) {
+		imx_pcm_dma_params_init_data(&ssi->filter_data_tx, res->start,
+			IMX_DMATYPE_SSI);
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx0");
+	if (res) {
+		imx_pcm_dma_params_init_data(&ssi->filter_data_rx, res->start,
+			IMX_DMATYPE_SSI);
+	}
+
+	platform_set_drvdata(pdev, ssi);
+
+	ret = snd_soc_set_ac97_ops(&imx_ssi_ac97_ops);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
+		goto failed_register;
+	}
+
+	ret = snd_soc_register_component(&pdev->dev, &imx_component,
+					 dai, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "register DAI failed\n");
+		goto failed_register;
+	}
+
+	ssi->fiq_params.irq = ssi->irq;
+	ssi->fiq_params.base = ssi->base;
+	ssi->fiq_params.dma_params_rx = &ssi->dma_params_rx;
+	ssi->fiq_params.dma_params_tx = &ssi->dma_params_tx;
+
+	ssi->fiq_init = imx_pcm_fiq_init(pdev, &ssi->fiq_params);
+	ssi->dma_init = imx_pcm_dma_init(pdev, IMX_SSI_DMABUF_SIZE);
+
+	if (ssi->fiq_init && ssi->dma_init) {
+		ret = ssi->fiq_init;
+		goto failed_pcm;
+	}
+
+	return 0;
+
+failed_pcm:
+	snd_soc_unregister_component(&pdev->dev);
+failed_register:
+	clk_disable_unprepare(ssi->clk);
+failed_clk:
+	snd_soc_set_ac97_ops(NULL);
+
+	return ret;
+}
+
+static int imx_ssi_remove(struct platform_device *pdev)
+{
+	struct imx_ssi *ssi = platform_get_drvdata(pdev);
+
+	if (!ssi->fiq_init)
+		imx_pcm_fiq_exit(pdev);
+
+	snd_soc_unregister_component(&pdev->dev);
+
+	if (ssi->flags & IMX_SSI_USE_AC97)
+		ac97_ssi = NULL;
+
+	clk_disable_unprepare(ssi->clk);
+	snd_soc_set_ac97_ops(NULL);
+
+	return 0;
+}
+
+static struct platform_driver imx_ssi_driver = {
+	.probe = imx_ssi_probe,
+	.remove = imx_ssi_remove,
+
+	.driver = {
+		.name = "imx-ssi",
+	},
+};
+
+module_platform_driver(imx_ssi_driver);
+
+/* Module information */
+MODULE_AUTHOR("Sascha Hauer, <s.hauer@pengutronix.de>");
+MODULE_DESCRIPTION("i.MX I2S/ac97 SoC Interface");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:imx-ssi");