[PATCH] USB: EHCI and Freescale 83xx quirk

On the MPC834x processors the multiport host (MPH) EHCI controller has an
erratum in which the port number in the queue head expects to be 0..N-1
instead of 1..N.  If we are on one of these chips we subtract one from
the port number before putting it into the queue head.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ehci-fsl.c

@@ -198,6 +198,16 @@ static void mpc83xx_usb_setup(struct usb_hcd *hcd)
 		mpc83xx_setup_phy(ehci, pdata->phy_mode, 0);
 
 	if (pdata->operating_mode == FSL_USB2_MPH_HOST) {
+		unsigned int chip, rev, svr;
+
+		svr = mfspr(SPRN_SVR);
+		chip = svr >> 16;
+		rev = (svr >> 4) & 0xf;
+
+		/* Deal with USB Erratum #14 on MPC834x Rev 1.0 & 1.1 chips */
+		if ((rev == 1) && (chip >= 0x8050) && (chip <= 0x8055))
+			ehci->has_fsl_port_bug = 1;
+
 		if (pdata->port_enables & FSL_USB2_PORT0_ENABLED)
 			mpc83xx_setup_phy(ehci, pdata->phy_mode, 0);
 		if (pdata->port_enables & FSL_USB2_PORT1_ENABLED)

drivers/usb/host/ehci-q.c

@@ -721,7 +721,14 @@ qh_make (
 		info1 |= maxp << 16;
 
 		info2 |= (EHCI_TUNE_MULT_TT << 30);
-		info2 |= urb->dev->ttport << 23;
+
+		/* Some Freescale processors have an erratum in which the
+		 * port number in the queue head was 0..N-1 instead of 1..N.
+		 */
+		if (ehci_has_fsl_portno_bug(ehci))
+			info2 |= (urb->dev->ttport-1) << 23;
+		else
+			info2 |= urb->dev->ttport << 23;
 
 		/* set the address of the TT; for TDI's integrated
 		 * root hub tt, leave it zeroed.

drivers/usb/host/ehci.h

@@ -88,8 +88,11 @@ struct ehci_hcd {			/* one per controller */
 	unsigned long		next_statechange;
 	u32			command;
 
+	/* SILICON QUIRKS */
 	unsigned		is_tdi_rh_tt:1;	/* TDI roothub with TT */
 	unsigned		no_selective_suspend:1;
+	unsigned		has_fsl_port_bug:1; /* FreeScale */
+
 	u8			sbrn;		/* packed release number */
 
 	/* irq statistics */
@@ -637,6 +640,18 @@ ehci_port_speed(struct ehci_hcd *ehci, unsigned int portsc)
 #define	ehci_port_speed(ehci, portsc)	(1<<USB_PORT_FEAT_HIGHSPEED)
 #endif
 
+/*-------------------------------------------------------------------------*/
+
+#ifdef CONFIG_PPC_83xx
+/* Some Freescale processors have an erratum in which the TT
+ * port number in the queue head was 0..N-1 instead of 1..N.
+ */
+#define	ehci_has_fsl_portno_bug(e)		((e)->has_fsl_port_bug)
+#else
+#define	ehci_has_fsl_portno_bug(e)		(0)
+#endif
+
+
 /*-------------------------------------------------------------------------*/
 
 #ifndef DEBUG