[PATCH v2 04/10] ASoC: sun4i-i2s: Add quirks to handle new compatible for reset

From: MylÃne Josserand
Date: Tue Jan 17 2017 - 09:04:57 EST


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: MylÃne Josserand <mylene.josserand@xxxxxxxxxxxxxxxxxx>
---
sound/soc/sunxi/sun4i-i2s.c | 57 +++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 55 insertions(+), 2 deletions(-)

diff --git a/sound/soc/sunxi/sun4i-i2s.c b/sound/soc/sunxi/sun4i-i2s.c
index 4237323ef594..3635bbc72cbc 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 = 8;

@@ -727,23 +766,37 @@ static int sun4i_i2s_probe(struct platform_device *pdev)
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);
--
2.11.0