From 4e64cd7763ca52dce5dff2c88f67a200f3aa37d3 Mon Sep 17 00:00:00 2001
From: Peter Geis <pgwipeout@gmail.com>
Date: Sat, 9 Apr 2022 11:21:15 -0400
Subject: [PATCH] usb: dwc3: fix backwards compat with rockchip devices
Git-commit: 4e64cd7763ca52dce5dff2c88f67a200f3aa37d3
References: jsc#PED-1817
Patch-mainline: v5.18-rc5

Commit 33fb697ec7e5 ("usb: dwc3: Get clocks individually") moved from
the clk_bulk api to individual clocks, following the snps,dwc3.yaml
dt-binding for clock names.
Unfortunately the rk3328 (and upcoming rk356x support) use the
rockchip,dwc3.yaml which has different clock names, which are common on
devices using the glue layer.
The rk3328 does not use a glue layer, but attaches directly to the dwc3
core driver.
The offending patch series failed to account for this, thus dwc3 was
broken on rk3328.

To retain backwards compatibility with rk3328 device trees we must also
check for the alternate clock names.

Fixes: 33fb697ec7e5 ("usb: dwc3: Get clocks individually")
Reported-by: Frank Wunderlich <frank-w@public-files.de>
Tested-By: Frank Wunderlich <frank-w@public-files.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Link: https://lore.kernel.org/r/20220409152116.3834354-1-pgwipeout@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/dwc3/core.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 1170b800acdc..5bfd3e88af35 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1690,21 +1690,44 @@ static int dwc3_probe(struct platform_device *pdev)
 		/*
 		 * Clocks are optional, but new DT platforms should support all
 		 * clocks as required by the DT-binding.
+		 * Some devices have different clock names in legacy device trees,
+		 * check for them to retain backwards compatibility.
 		 */
 		dwc->bus_clk = devm_clk_get_optional(dev, "bus_early");
 		if (IS_ERR(dwc->bus_clk))
 			return dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
 					     "could not get bus clock\n");
 
+		if (dwc->bus_clk == NULL) {
+			dwc->bus_clk = devm_clk_get_optional(dev, "bus_clk");
+			if (IS_ERR(dwc->bus_clk))
+				return dev_err_probe(dev, PTR_ERR(dwc->bus_clk),
+						     "could not get bus clock\n");
+		}
+
 		dwc->ref_clk = devm_clk_get_optional(dev, "ref");
 		if (IS_ERR(dwc->ref_clk))
 			return dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
 					     "could not get ref clock\n");
 
+		if (dwc->ref_clk == NULL) {
+			dwc->ref_clk = devm_clk_get_optional(dev, "ref_clk");
+			if (IS_ERR(dwc->ref_clk))
+				return dev_err_probe(dev, PTR_ERR(dwc->ref_clk),
+						     "could not get ref clock\n");
+		}
+
 		dwc->susp_clk = devm_clk_get_optional(dev, "suspend");
 		if (IS_ERR(dwc->susp_clk))
 			return dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
 					     "could not get suspend clock\n");
+
+		if (dwc->susp_clk == NULL) {
+			dwc->susp_clk = devm_clk_get_optional(dev, "suspend_clk");
+			if (IS_ERR(dwc->susp_clk))
+				return dev_err_probe(dev, PTR_ERR(dwc->susp_clk),
+						     "could not get suspend clock\n");
+		}
 	}
 
 	ret = reset_control_deassert(dwc->reset);
-- 
2.35.3