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* [PATCH] usb: dwc3: core: power on PHYs before initializing core
@ 2018-01-12  4:00 ` William Wu
  0 siblings, 0 replies; 18+ messages in thread
From: William Wu @ 2018-01-12  4:00 UTC (permalink / raw)
  To: balbi-DgEjT+Ai2ygdnm+yROfE0A,
	gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r
  Cc: huangtao-TNX95d0MmH7DzftRWevZcw, heiko-4mtYJXux2i+zQB+pC5nmwQ,
	groeck-hpIqsD4AKlfQT0dZR+AlfA, frank.wang-TNX95d0MmH7DzftRWevZcw,
	linux-usb-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA,
	dianders-hpIqsD4AKlfQT0dZR+AlfA, lin.huang-TNX95d0MmH7DzftRWevZcw,
	linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
	william.wu-TNX95d0MmH7DzftRWevZcw,
	briannorris-hpIqsD4AKlfQT0dZR+AlfA,
	John.Youn-HKixBCOQz3hWk0Htik3J/w,
	daniel.meng-TNX95d0MmH7DzftRWevZcw

The dwc3_core_init() gets the PHYs and initializes the PHYs with
the usb_phy_init() and phy_init() functions before initializing
core, and power on the PHYs after core initialization is done.

However, some platforms (e.g. Rockchip RK3399 DWC3 with Type-C
USB3 PHY), it needs to do some special operation while power on
the Type-C PHY before initializing DWC3 core. It's because that
the RK3399 Type-C PHY requires to hold the DWC3 controller in
reset state to keep the PIPE power state in P2 while configuring
the Type-C PHY, otherwise, it may cause waiting for the PIPE ready
timeout. In this case, if we power on the PHYs after the DWC3 core
initialization is done, the core will be reset to uninitialized
state after power on the PHYs.

Fix this by powering on the PHYs before initializing core. And
because the GUID register may also be reset in this case, so we
need to configure the GUID register after powering on the PHYs.

Signed-off-by: William Wu <william.wu-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/usb/dwc3/core.c | 46 ++++++++++++++++++++++------------------------
 1 file changed, 22 insertions(+), 24 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index c32d2b9..4f5573f 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -741,12 +741,6 @@ static int dwc3_core_init(struct dwc3 *dwc)
 		goto err0;
 	}
 
-	/*
-	 * Write Linux Version Code to our GUID register so it's easy to figure
-	 * out which kernel version a bug was found.
-	 */
-	dwc3_writel(dwc->regs, DWC3_GUID, LINUX_VERSION_CODE);
-
 	/* Handle USB2.0-only core configuration */
 	if (DWC3_GHWPARAMS3_SSPHY_IFC(dwc->hwparams.hwparams3) ==
 			DWC3_GHWPARAMS3_SSPHY_IFC_DIS) {
@@ -762,34 +756,40 @@ static int dwc3_core_init(struct dwc3 *dwc)
 	if (ret)
 		goto err0;
 
+	usb_phy_set_suspend(dwc->usb2_phy, 0);
+	usb_phy_set_suspend(dwc->usb3_phy, 0);
+	ret = phy_power_on(dwc->usb2_generic_phy);
+	if (ret < 0)
+		goto err1;
+
+	ret = phy_power_on(dwc->usb3_generic_phy);
+	if (ret < 0)
+		goto err2;
+
 	ret = dwc3_phy_setup(dwc);
 	if (ret)
-		goto err0;
+		goto err3;
+
+	/*
+	 * Write Linux Version Code to our GUID register so it's easy to figure
+	 * out which kernel version a bug was found.
+	 */
+	dwc3_writel(dwc->regs, DWC3_GUID, LINUX_VERSION_CODE);
 
 	dwc3_core_setup_global_control(dwc);
 	dwc3_core_num_eps(dwc);
 
 	ret = dwc3_setup_scratch_buffers(dwc);
 	if (ret)
-		goto err1;
+		goto err3;
 
 	/* Adjust Frame Length */
 	dwc3_frame_length_adjustment(dwc);
 
-	usb_phy_set_suspend(dwc->usb2_phy, 0);
-	usb_phy_set_suspend(dwc->usb3_phy, 0);
-	ret = phy_power_on(dwc->usb2_generic_phy);
-	if (ret < 0)
-		goto err2;
-
-	ret = phy_power_on(dwc->usb3_generic_phy);
-	if (ret < 0)
-		goto err3;
-
 	ret = dwc3_event_buffers_setup(dwc);
 	if (ret) {
 		dev_err(dwc->dev, "failed to setup event buffers\n");
-		goto err4;
+		goto err3;
 	}
 
 	/*
@@ -821,17 +821,15 @@ static int dwc3_core_init(struct dwc3 *dwc)
 
 	return 0;
 
-err4:
+err3:
 	phy_power_off(dwc->usb3_generic_phy);
 
-err3:
+err2:
 	phy_power_off(dwc->usb2_generic_phy);
 
-err2:
+err1:
 	usb_phy_set_suspend(dwc->usb2_phy, 1);
 	usb_phy_set_suspend(dwc->usb3_phy, 1);
-
-err1:
 	usb_phy_shutdown(dwc->usb2_phy);
 	usb_phy_shutdown(dwc->usb3_phy);
 	phy_exit(dwc->usb2_generic_phy);
-- 
2.0.0

^ permalink raw reply related	[flat|nested] 18+ messages in thread

end of thread, other threads:[~2018-03-09  9:01 UTC | newest]

Thread overview: 18+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-01-12  4:00 [PATCH] usb: dwc3: core: power on PHYs before initializing core William Wu
2018-01-12  4:00 ` William Wu
2018-01-12  4:00 ` William Wu
2018-01-17 21:46 ` [PATCH] " Brian Norris
2018-01-17 21:46   ` Brian Norris
     [not found]   ` <20180117214601.GA111796-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2018-01-18 16:51     ` [PATCH] " Enric Balletbo Serra
2018-01-18 16:51       ` Enric Balletbo Serra
2018-01-18 16:51       ` Enric Balletbo Serra
     [not found] ` <1515729616-8639-1-git-send-email-william.wu-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
2018-03-08 10:43   ` [PATCH] " Felipe Balbi
2018-03-08 10:43     ` Felipe Balbi
2018-03-08 10:43     ` Felipe Balbi
2018-03-08 16:49     ` [PATCH] " Brian Norris
2018-03-08 16:49       ` Brian Norris
     [not found]       ` <20180308164916.GA65031-rgVyoJUnxu4fQXCR9C5MjtfHHWVUegAGYJqu5kTmcBRl57MIdRCFDg@public.gmane.org>
2018-03-09  8:54         ` [PATCH] " Roger Quadros
2018-03-09  8:54           ` Roger Quadros
2018-03-09  8:54           ` Roger Quadros
2018-03-09  9:01           ` [PATCH] " Felipe Balbi
2018-03-09  9:01             ` Felipe Balbi

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