ASoC: rockchip: pdm: Add support for path map

This patch adds property 'rockchip,path-map' for path mapping.

e.g.

"rockchip,path-map = <3 2 1 0>" means the mapping as follows:

  path0 <-- sdi3
  path1 <-- sdi2
  path2 <-- sdi1
  path3 <-- sdi0
Signed-off-by: NSugar Zhang <sugar.zhang@rock-chips.com>
Link: https://lore.kernel.org/r/1630675410-3354-5-git-send-email-sugar.zhang@rock-chips.comSigned-off-by: NMark Brown <broonie@kernel.org>

sound/soc/rockchip/rockchip_pdm.c

@@ -20,6 +20,7 @@
 
 #define PDM_DMA_BURST_SIZE	(8) /* size * width: 8*4 = 32 bytes */
 #define PDM_SIGNOFF_CLK_RATE	(100000000)
+#define PDM_PATH_MAX		(4)
 
 enum rk_pdm_version {
 	RK_PDM_RK3229,
@@ -539,8 +540,36 @@ static const struct of_device_id rockchip_pdm_match[] __maybe_unused = {
 };
 MODULE_DEVICE_TABLE(of, rockchip_pdm_match);
 
+static int rockchip_pdm_path_parse(struct rk_pdm_dev *pdm, struct device_node *node)
+{
+	unsigned int path[PDM_PATH_MAX];
+	int cnt = 0, ret = 0, i = 0, val = 0, msk = 0;
+
+	cnt = of_count_phandle_with_args(node, "rockchip,path-map",
+					 NULL);
+	if (cnt != PDM_PATH_MAX)
+		return cnt;
+
+	ret = of_property_read_u32_array(node, "rockchip,path-map",
+					 path, cnt);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < cnt; i++) {
+		if (path[i] >= PDM_PATH_MAX)
+			return -EINVAL;
+		msk |= PDM_PATH_MASK(i);
+		val |= PDM_PATH(i, path[i]);
+	}
+
+	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, msk, val);
+
+	return 0;
+}
+
 static int rockchip_pdm_probe(struct platform_device *pdev)
 {
+	struct device_node *node = pdev->dev.of_node;
 	const struct of_device_id *match;
 	struct rk_pdm_dev *pdm;
 	struct resource *res;
@@ -606,6 +635,11 @@ static int rockchip_pdm_probe(struct platform_device *pdev)
 	}
 
 	rockchip_pdm_rxctrl(pdm, 0);
+
+	ret = rockchip_pdm_path_parse(pdm, node);
+	if (ret != 0 && ret != -ENOENT)
+		goto err_suspend;
+
 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
 	if (ret) {
 		dev_err(&pdev->dev, "could not register pcm: %d\n", ret);

sound/soc/rockchip/rockchip_pdm.h

@@ -53,6 +53,9 @@
 #define PDM_FD_DENOMINATOR_MSK	GENMASK(15, 0)
 
 /* PDM CLK CTRL */
+#define PDM_PATH_SHIFT(x)	(8 + (x) * 2)
+#define PDM_PATH_MASK(x)	(0x3 << PDM_PATH_SHIFT(x))
+#define PDM_PATH(x, v)		((v) << PDM_PATH_SHIFT(x))
 #define PDM_CLK_FD_RATIO_MSK	BIT(6)
 #define PDM_CLK_FD_RATIO_40	(0X0 << 6)
 #define PDM_CLK_FD_RATIO_35	BIT(6)