[PATCH v3 2/4] usb: dwc3: xilinx: Introduce dwc3_xlnx_config for per-platform data

[Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>]

Replace the direct pltfm_init function pointer in struct dwc3_xlnx with
a const pointer to a new struct dwc3_xlnx_config. This groups
per-platform configuration in one place and allows future patches to add
platform-specific fields (e.g. tx_deemph) without growing dwc3_xlnx.

While at it, switch from of_match_node() to device_get_match_data() to
simplify the match data lookup.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
---
Changes for v3:
- Add check if dwc3_config exists.

Changes for v2:
- New patch, split from "Add Versal2 MMI USB 3.2 controller support".
- Use device_get_match_data() instead of of_match_node().
---
 drivers/usb/dwc3/dwc3-xilinx.c | 31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-xilinx.c b/drivers/usb/dwc3/dwc3-xilinx.c
index f41b0da5e89d..af0ccd060c8b 100644
--- a/drivers/usb/dwc3/dwc3-xilinx.c
+++ b/drivers/usb/dwc3/dwc3-xilinx.c
@@ -12,6 +12,7 @@
 #include <linux/clk.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/dma-mapping.h>
 #include <linux/gpio/consumer.h>
 #include <linux/of_platform.h>
@@ -41,12 +42,18 @@
 #define XLNX_USB_FPD_POWER_PRSNT		0x80
 #define FPD_POWER_PRSNT_OPTION			BIT(0)
 
+struct dwc3_xlnx;
+
+struct dwc3_xlnx_config {
+	int				(*pltfm_init)(struct dwc3_xlnx *data);
+};
+
 struct dwc3_xlnx {
 	int				num_clocks;
 	struct clk_bulk_data		*clks;
 	struct device			*dev;
 	void __iomem			*regs;
-	int				(*pltfm_init)(struct dwc3_xlnx *data);
+	const struct dwc3_xlnx_config	*dwc3_config;
 	struct phy			*usb3_phy;
 };
 
@@ -241,14 +248,22 @@ static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
 	return ret;
 }
 
+static const struct dwc3_xlnx_config zynqmp_config = {
+	.pltfm_init = dwc3_xlnx_init_zynqmp,
+};
+
+static const struct dwc3_xlnx_config versal_config = {
+	.pltfm_init = dwc3_xlnx_init_versal,
+};
+
 static const struct of_device_id dwc3_xlnx_of_match[] = {
 	{
 		.compatible = "xlnx,zynqmp-dwc3",
-		.data = &dwc3_xlnx_init_zynqmp,
+		.data = &zynqmp_config,
 	},
 	{
 		.compatible = "xlnx,versal-dwc3",
-		.data = &dwc3_xlnx_init_versal,
+		.data = &versal_config,
 	},
 	{ /* Sentinel */ }
 };
@@ -284,7 +299,6 @@ static int dwc3_xlnx_probe(struct platform_device *pdev)
 	struct dwc3_xlnx		*priv_data;
 	struct device			*dev = &pdev->dev;
 	struct device_node		*np = dev->of_node;
-	const struct of_device_id	*match;
 	void __iomem			*regs;
 	int				ret;
 
@@ -296,9 +310,10 @@ static int dwc3_xlnx_probe(struct platform_device *pdev)
 	if (IS_ERR(regs))
 		return dev_err_probe(dev, PTR_ERR(regs), "failed to map registers\n");
 
-	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
-
-	priv_data->pltfm_init = match->data;
+	priv_data->dwc3_config = device_get_match_data(dev);
+	if (!priv_data->dwc3_config)
+		return dev_err_probe(dev, -ENODEV,
+				     "missing dwc3 platform configuration\n");
 	priv_data->regs = regs;
 	priv_data->dev = dev;
 
@@ -314,7 +329,7 @@ static int dwc3_xlnx_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	ret = priv_data->pltfm_init(priv_data);
+	ret = priv_data->dwc3_config->pltfm_init(priv_data);
 	if (ret)
 		goto err_clk_put;
 
-- 
2.43.0