ASoC: sun4i-i2s: Add quirks to handle a31 compatible

Some SoCs have a reset line that must be asserted/deasserted.
This patch adds a quirk to handle the new compatible
"allwinner,sun6i-a31-i2s" which will deassert the reset
line on probe function and assert it on remove's one.

This new compatible is useful in case of A33 codec driver, for example.

Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 55 insertions, 2 deletions

diff --git a/sound/soc/sunxi/sun4i-i2s.c b/sound/soc/sunxi/sun4i-i2s.c
index f24d19526603..268f2bf691b3 100644
--- a/sound/soc/sunxi/sun4i-i2s.c
+++ b/sound/soc/sunxi/sun4i-i2s.c
@@ -14,9 +14,11 @@
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/reset.h>
 
 #include <sound/dmaengine_pcm.h>
 #include <sound/pcm_params.h>
@@ -92,6 +94,7 @@ struct sun4i_i2s {
         struct clk      *bus_clk;
         struct clk      *mod_clk;
         struct regmap   *regmap;
+        struct reset_control *rst;
 
         unsigned int    mclk_freq;
 
@@ -651,9 +654,22 @@ static int sun4i_i2s_runtime_suspend(struct device *dev)
         return 0;
 }
 
+struct sun4i_i2s_quirks {
+        bool has_reset;
+};
+
+static const struct sun4i_i2s_quirks sun4i_a10_i2s_quirks = {
+        .has_reset      = false,
+};
+
+static const struct sun4i_i2s_quirks sun6i_a31_i2s_quirks = {
+        .has_reset      = true,
+};
+
 static int sun4i_i2s_probe(struct platform_device *pdev)
 {
         struct sun4i_i2s *i2s;
+        const struct sun4i_i2s_quirks *quirks;
         struct resource *res;
         void __iomem *regs;
         int irq, ret;
@@ -674,6 +690,12 @@ static int sun4i_i2s_probe(struct platform_device *pdev)
                 return irq;
         }
 
+        quirks = of_device_get_match_data(&pdev->dev);
+        if (!quirks) {
+                dev_err(&pdev->dev, "Failed to determine the quirks to use\n");
+                return -ENODEV;
+        }
+
         i2s->bus_clk = devm_clk_get(&pdev->dev, "apb");
         if (IS_ERR(i2s->bus_clk)) {
                 dev_err(&pdev->dev, "Can't get our bus clock\n");
@@ -692,7 +714,24 @@ static int sun4i_i2s_probe(struct platform_device *pdev)
                 dev_err(&pdev->dev, "Can't get our mod clock\n");
                 return PTR_ERR(i2s->mod_clk);
         }
-        
+
+        if (quirks->has_reset) {
+                i2s->rst = devm_reset_control_get(&pdev->dev, NULL);
+                if (IS_ERR(i2s->rst)) {
+                        dev_err(&pdev->dev, "Failed to get reset control\n");
+                        return PTR_ERR(i2s->rst);
+                }
+        }
+
+        if (!IS_ERR(i2s->rst)) {
+                ret = reset_control_deassert(i2s->rst);
+                if (ret) {
+                        dev_err(&pdev->dev,
+                                "Failed to deassert the reset control\n");
+                        return -EINVAL;
+                }
+        }
+
         i2s->playback_dma_data.addr = res->start + SUN4I_I2S_FIFO_TX_REG;
         i2s->playback_dma_data.maxburst = 4;
 
@@ -727,23 +766,37 @@ err_suspend:
                 sun4i_i2s_runtime_suspend(&pdev->dev);
 err_pm_disable:
         pm_runtime_disable(&pdev->dev);
+        if (!IS_ERR(i2s->rst))
+                reset_control_assert(i2s->rst);
 
         return ret;
 }
 
 static int sun4i_i2s_remove(struct platform_device *pdev)
 {
+        struct sun4i_i2s *i2s = dev_get_drvdata(&pdev->dev);
+
         snd_dmaengine_pcm_unregister(&pdev->dev);
 
         pm_runtime_disable(&pdev->dev);
         if (!pm_runtime_status_suspended(&pdev->dev))
                 sun4i_i2s_runtime_suspend(&pdev->dev);
 
+        if (!IS_ERR(i2s->rst))
+                reset_control_assert(i2s->rst);
+
         return 0;
 }
 
 static const struct of_device_id sun4i_i2s_match[] = {
-        { .compatible = "allwinner,sun4i-a10-i2s", },
+        {
+                .compatible = "allwinner,sun4i-a10-i2s",
+                .data = &sun4i_a10_i2s_quirks,
+        },
+        {
+                .compatible = "allwinner,sun6i-a31-i2s",
+                .data = &sun6i_a31_i2s_quirks,
+        },
         {}
 };
 MODULE_DEVICE_TABLE(of, sun4i_i2s_match);