[PATCH] usb: mtu3: Don't check the USB3 status bits if the max speed is USB2

[PATCH] usb: mtu3: Don't check the USB3 status bits if the max speed is USB2

[amergnat]

From: Alexandre Bailon <abailon@baylibre.com>

If the IP is U3, the driver will check some USB3 status bits.
This could fail if only USB2 is used.
This only check these bits if USB operate at USB3 speed.

Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
Signed-off-by: Fabien Parent <fparent@baylibre.com>
Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
---
This patch is ported from downstream. Without this fix, USB doesn't
work if USB2 protocol is used first.
---
 drivers/usb/mtu3/mtu3_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/mtu3/mtu3_core.c b/drivers/usb/mtu3/mtu3_core.c
index a3a6282893d0..00dba871aff8 100644
--- a/drivers/usb/mtu3/mtu3_core.c
+++ b/drivers/usb/mtu3/mtu3_core.c
@@ -100,7 +100,7 @@ static int mtu3_device_enable(struct mtu3 *mtu)
 
 	mtu3_clrbits(ibase, U3D_SSUSB_IP_PW_CTRL2, SSUSB_IP_DEV_PDN);
 
-	if (mtu->u3_capable) {
+	if (mtu->u3_capable && mtu->max_speed >= USB_SPEED_SUPER) {
 		check_clk = SSUSB_U3_MAC_RST_B_STS;
 		mtu3_clrbits(ibase, SSUSB_U3_CTRL(0),
 			(SSUSB_U3_PORT_DIS | SSUSB_U3_PORT_PDN |

---
base-commit: fe15c26ee26efa11741a7b632e9f23b01aca4cc6
change-id: 20230426-usb-mtu3-improvement-77d987def9fe

Best regards,
-- 
Alexandre Mergnat <amergnat@baylibre.com>

Re: [PATCH] usb: mtu3: Don't check the USB3 status bits if the max speed is USB2

[Chunfeng Yun (云春峰)]

On Wed, 2023-04-26 at 21:24 +0200, amergnat@baylibre.com wrote:
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
> 
> 
> From: Alexandre Bailon <abailon@baylibre.com>
> 
> If the IP is U3, the driver will check some USB3 status bits.
> This could fail if only USB2 is used.
> This only check these bits if USB operate at USB3 speed.
> 
> Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
> Signed-off-by: Fabien Parent <fparent@baylibre.com>
> Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
> ---
> This patch is ported from downstream. Without this fix, USB doesn't
> work if USB2 protocol is used first.
> ---
>  drivers/usb/mtu3/mtu3_core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/mtu3/mtu3_core.c
> b/drivers/usb/mtu3/mtu3_core.c
> index a3a6282893d0..00dba871aff8 100644
> --- a/drivers/usb/mtu3/mtu3_core.c
> +++ b/drivers/usb/mtu3/mtu3_core.c
> @@ -100,7 +100,7 @@ static int mtu3_device_enable(struct mtu3 *mtu)
> 
>         mtu3_clrbits(ibase, U3D_SSUSB_IP_PW_CTRL2, SSUSB_IP_DEV_PDN);
> 
> -       if (mtu->u3_capable) {
> +       if (mtu->u3_capable && mtu->max_speed >= USB_SPEED_SUPER) {
NAK

Maybe you misunderstand the usage of @u3_capable, if you only use u2
function but the controller support u3 function, shall disable u3 by  
property "mediatek,u3p-dis-msk", then no need check speed here.

Thanks

>                 check_clk = SSUSB_U3_MAC_RST_B_STS;
>                 mtu3_clrbits(ibase, SSUSB_U3_CTRL(0),
>                         (SSUSB_U3_PORT_DIS | SSUSB_U3_PORT_PDN |
> 
> ---
> base-commit: fe15c26ee26efa11741a7b632e9f23b01aca4cc6
> change-id: 20230426-usb-mtu3-improvement-77d987def9fe
> 
> Best regards,
> --
> Alexandre Mergnat <amergnat@baylibre.com>
>