usb: host: xhci-plat: add support for the R-Car H3 xHCI controllers

The R-Car H3 has two xHCI controllers. This SoC is compatible with
R-Car Gen2 SoCs, however this SoC doesn't need some specific registers
setting, and need a new firmware.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci-rcar.c

@@ -17,7 +17,14 @@
 #include "xhci-plat.h"
 #include "xhci-rcar.h"
 
+/*
+* - The V2 firmware is possible to use on R-Car Gen2. However, the V2 causes
+*   performance degradation. So, this driver continues to use the V1 if R-Car
+*   Gen2.
+* - The V1 firmware is impossible to use on R-Car Gen3.
+*/
 MODULE_FIRMWARE(XHCI_RCAR_FIRMWARE_NAME_V1);
+MODULE_FIRMWARE(XHCI_RCAR_FIRMWARE_NAME_V2);
 
 /*** Register Offset ***/
 #define RCAR_USB3_INT_ENA	0x224	/* Interrupt Enable */