ASoC: rockchip: i2s: configure the sdio pins' iomux mode

There are 3 i2s sdio pins, which iomux mode is as follows:

 - sdi3_sdo1
 - sdi2_sdo2
 - sdi1_sdo3

we need to configure these pins' iomux mode via the GRF register
when use multi channel playback/capture.
Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/rockchip-i2s.txt

@@ -23,6 +23,11 @@ Required properties:
 - rockchip,playback-channels: max playback channels, if not set, 8 channels default.
 - rockchip,capture-channels: max capture channels, if not set, 2 channels default.
 
+Required properties for controller which support multi channels
+playback/capture:
+
+- rockchip,grf: the phandle of the syscon node for GRF register.
+
 Example for rk3288 I2S controller:
 
 i2s@ff890000 {

sound/soc/rockchip/rockchip_i2s.c

@@ -11,8 +11,10 @@
  */
 
 #include <linux/module.h>
+#include <linux/mfd/syscon.h>
 #include <linux/delay.h>
 #include <linux/of_gpio.h>
+#include <linux/of_device.h>
 #include <linux/clk.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
@@ -23,6 +25,11 @@
 
 #define DRV_NAME "rockchip-i2s"
 
+struct rk_i2s_pins {
+	u32 reg_offset;
+	u32 shift;
+};
+
 struct rk_i2s_dev {
 	struct device *dev;
 
@@ -33,6 +40,7 @@ struct rk_i2s_dev {
 	struct snd_dmaengine_dai_dma_data playback_dma_data;
 
 	struct regmap *regmap;
+	struct regmap *grf;
 
 /*
  * Used to indicate the tx/rx status.
@@ -42,6 +50,7 @@ struct rk_i2s_dev {
 	bool tx_start;
 	bool rx_start;
 	bool is_master_mode;
+	const struct rk_i2s_pins *pins;
 };
 
 static int i2s_runtime_suspend(struct device *dev)
@@ -300,6 +309,30 @@ static int rockchip_i2s_hw_params(struct snd_pcm_substream *substream,
 				   I2S_TXCR_VDW_MASK | I2S_TXCR_CSR_MASK,
 				   val);
 
+	if (!IS_ERR(i2s->grf) && i2s->pins) {
+		regmap_read(i2s->regmap, I2S_TXCR, &val);
+		val &= I2S_TXCR_CSR_MASK;
+
+		switch (val) {
+		case I2S_CHN_4:
+			val = I2S_IO_4CH_OUT_6CH_IN;
+			break;
+		case I2S_CHN_6:
+			val = I2S_IO_6CH_OUT_4CH_IN;
+			break;
+		case I2S_CHN_8:
+			val = I2S_IO_8CH_OUT_2CH_IN;
+			break;
+		default:
+			val = I2S_IO_2CH_OUT_8CH_IN;
+			break;
+		}
+
+		val <<= i2s->pins->shift;
+		val |= (I2S_IO_DIRECTION_MASK << i2s->pins->shift) << 16;
+		regmap_write(i2s->grf, i2s->pins->reg_offset, val);
+	}
+
 	regmap_update_bits(i2s->regmap, I2S_DMACR, I2S_DMACR_TDL_MASK,
 			   I2S_DMACR_TDL(16));
 	regmap_update_bits(i2s->regmap, I2S_DMACR, I2S_DMACR_RDL_MASK,
@@ -485,9 +518,23 @@ static const struct regmap_config rockchip_i2s_regmap_config = {
 	.cache_type = REGCACHE_FLAT,
 };
 
+static const struct rk_i2s_pins rk3399_i2s_pins = {
+	.reg_offset = 0xe220,
+	.shift = 11,
+};
+
+static const struct of_device_id rockchip_i2s_match[] = {
+	{ .compatible = "rockchip,rk3066-i2s", },
+	{ .compatible = "rockchip,rk3188-i2s", },
+	{ .compatible = "rockchip,rk3288-i2s", },
+	{ .compatible = "rockchip,rk3399-i2s", .data = &rk3399_i2s_pins },
+	{},
+};
+
 static int rockchip_i2s_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node;
+	const struct of_device_id *of_id;
 	struct rk_i2s_dev *i2s;
 	struct snd_soc_dai_driver *soc_dai;
 	struct resource *res;
@@ -501,6 +548,17 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
+	i2s->dev = &pdev->dev;
+
+	i2s->grf = syscon_regmap_lookup_by_phandle(node, "rockchip,grf");
+	if (!IS_ERR(i2s->grf)) {
+		of_id = of_match_device(rockchip_i2s_match, &pdev->dev);
+		if (!of_id || !of_id->data)
+			return -EINVAL;
+
+		i2s->pins = of_id->data;
+	}
+
 	/* try to prepare related clocks */
 	i2s->hclk = devm_clk_get(&pdev->dev, "i2s_hclk");
 	if (IS_ERR(i2s->hclk)) {
@@ -540,7 +598,6 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
 	i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 	i2s->capture_dma_data.maxburst = 4;
 
-	i2s->dev = &pdev->dev;
 	dev_set_drvdata(&pdev->dev, i2s);
 
 	pm_runtime_enable(&pdev->dev);
@@ -606,14 +663,6 @@ static int rockchip_i2s_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id rockchip_i2s_match[] = {
-	{ .compatible = "rockchip,rk3066-i2s", },
-	{ .compatible = "rockchip,rk3188-i2s", },
-	{ .compatible = "rockchip,rk3288-i2s", },
-	{ .compatible = "rockchip,rk3399-i2s", },
-	{},
-};
-
 static const struct dev_pm_ops rockchip_i2s_pm_ops = {
 	SET_RUNTIME_PM_OPS(i2s_runtime_suspend, i2s_runtime_resume,
 			   NULL)

sound/soc/rockchip/rockchip_i2s.h

@@ -236,4 +236,11 @@ enum {
 #define I2S_TXDR	(0x0024)
 #define I2S_RXDR	(0x0028)
 
+/* io direction cfg register */
+#define I2S_IO_DIRECTION_MASK	(7)
+#define I2S_IO_8CH_OUT_2CH_IN	(0)
+#define I2S_IO_6CH_OUT_4CH_IN	(4)
+#define I2S_IO_4CH_OUT_6CH_IN	(6)
+#define I2S_IO_2CH_OUT_8CH_IN	(7)
+
 #endif /* _ROCKCHIP_IIS_H */