[PATCH 10/10 (v2)] bcm63xx: clarify meaning of the magical value in ehci-bcm63xx.c

[Maxime Bizon <mbizon@freebox.fr>]

USB maintainer asked for clarification of the magic value used during
USB init. Be clear about the source of it.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
---
 drivers/usb/host/ehci-bcm63xx.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/usb/host/ehci-bcm63xx.c b/drivers/usb/host/ehci-bcm63xx.c
index 8a62c0a..c2b3e7f 100644
--- a/drivers/usb/host/ehci-bcm63xx.c
+++ b/drivers/usb/host/ehci-bcm63xx.c
@@ -78,7 +78,11 @@ static int __devinit ehci_hcd_bcm63xx_drv_probe(struct 
platform_device *pdev)
        reg |= USBH_PRIV_SWAP_EHCI_ENDN_MASK;
        bcm_rset_writel(RSET_USBH_PRIV, reg, USBH_PRIV_SWAP_REG);
 
-       /* don't ask... */
+       /*
+        * The magic value comes for the original vendor BSP and is
+        * needed for USB to work. Datasheet does not help, so the
+        * magic value is used as-is.
+        */
        bcm_rset_writel(RSET_USBH_PRIV, 0x1c0020, USBH_PRIV_TEST_REG);
 
        hcd = usb_create_hcd(&ehci_bcm63xx_hc_driver, &pdev->dev, "bcm63xx");
-- 
1.6.0.4