Commit 7bea22b1 authored Sep 18, 2017 by Mathias Nyman Committed by Greg Kroah-Hartman Sep 18, 2017

xhci: set missing SuperSpeedPlus Link Protocol bit in roothub descriptor



A SuperSpeedPlus roothub needs to have the Link Protocol (LP) bit set in
the bmSublinkSpeedAttr[] entry of a SuperSpeedPlus descriptor.

If the xhci controller has an optional Protocol Speed ID (PSI) table then
that will be used as a base to create the roothub SuperSpeedPlus
descriptor.
The PSI table does not however necessary contain the LP bit so we need
to set it manually.

Check the psi speed and set LP bit if speed is 10Gbps or higher.
We're not setting it for 5 to 10Gbps as USB 3.1 specification always
mention SuperSpeedPlus for 10Gbps or higher, and some SSIC USB 3.0 speeds
can be over 5Gbps, such as SSIC-G3B-L1 at 5830 Mbps

Cc: <stable@vger.kernel.org> # 4.6+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4ec1cd3e

drivers/usb/host/xhci-hub.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -112,7 +112,7 @@ static int xhci_create_usb3_bos_desc(struct xhci_hcd xhci, char buf,

		/* If PSI table exists, add the custom speed attributes from it */
		if (usb3_1 && xhci->usb3_rhub.psi_count) {
		u32 ssp_cap_base, bm_attrib, psi;
		u32 ssp_cap_base, bm_attrib, psi, psi_mant, psi_exp;
		int offset;

		ssp_cap_base = USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE;
		@@ -139,6 +139,15 @@ static int xhci_create_usb3_bos_desc(struct xhci_hcd xhci, char buf,
		for (i = 0; i < xhci->usb3_rhub.psi_count; i++) {
		psi = xhci->usb3_rhub.psi[i];
		psi &= ~USB_SSP_SUBLINK_SPEED_RSVD;
		psi_exp = XHCI_EXT_PORT_PSIE(psi);
		psi_mant = XHCI_EXT_PORT_PSIM(psi);

		/* Shift to Gbps and set SSP Link BIT(14) if 10Gpbs */
		for (; psi_exp < 3; psi_exp++)
		psi_mant /= 1000;
		if (psi_mant >= 10)
		psi \|= BIT(14);

		if ((psi & PLT_MASK) == PLT_SYM) {
		/* Symmetric, create SSA RX and TX from one PSI entry */
		put_unaligned_le32(psi, &buf[offset]);

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