4.15-stable review patch. If anyone has any objections, please let me know.
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From: Al Cooper al.cooper@broadcom.com
commit 0aa0c12262fd848c48448c39ff6c1c097be00dd4 upstream.
This is caused by a bug in the BDC core. When the BDC core comes out of reset and it's not selected, it gets a backup clock. When the BDC core is selected, it get's the main clock. If HOST mode is then selected the BDC core has the main clock shut off but the backup clock is not restored.
The failure scenario and cause are as follows: - DRD mode is active - Device mode is selected first in bootloader - When host mode is now selected, the clock to the BDC is cut off. - BDC registers are inaccessible and therefore the BDC driver crashes upon Linux boot.
The fix is to have the phy driver always force a BDC reset on startup.
Fixes: 49859e55e364 ("phy: usb: phy-brcm-usb: Add Broadcom STB USB phy driver") Signed-off-by: Al Cooper alcooperx@gmail.com Acked-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: Kishon Vijay Abraham I kishon@ti.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/phy/broadcom/phy-brcm-usb-init.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/phy/broadcom/phy-brcm-usb-init.c +++ b/drivers/phy/broadcom/phy-brcm-usb-init.c @@ -917,6 +917,7 @@ void brcm_usb_init_common(struct brcm_us USB_CTRL_UNSET_FAMILY(params, USB_PM, BDC_SOFT_RESETB); break; default: + USB_CTRL_UNSET_FAMILY(params, USB_PM, BDC_SOFT_RESETB); USB_CTRL_SET_FAMILY(params, USB_PM, BDC_SOFT_RESETB); break; }