From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Roese Date: Mon, 14 Mar 2016 11:18:12 +0100 Subject: [U-Boot] [PATCH v3 3/4] usb: Don't reset the USB hub a 2nd time In-Reply-To: <1457950693-564-1-git-send-email-sr@denx.de> References: <1457950693-564-1-git-send-email-sr@denx.de> Message-ID: <1457950693-564-4-git-send-email-sr@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Debugging has shown, that all USB hubs are being resetted twice while USB scanning. This introduces additional delays and makes USB scanning even more slow. Testing has shown that this 2nd USB hub reset doesn't seem to be necessary. This patch now removes this 2nd USB hub reset. Resulting in faster USB scan time. Here the current numbers: Without this patch: => time usb start starting USB... USB0: USB EHCI 1.00 scanning bus 0 for devices... 9 USB Device(s) found time: 24.003 seconds With this patch: => time usb start starting USB... USB0: USB EHCI 1.00 scanning bus 0 for devices... 9 USB Device(s) found time: 20.392 seconds So ~3.6 seconds of USB scanning time reduction. Signed-off-by: Stefan Roese Cc: Simon Glass Cc: Hans de Goede Tested-by: Stephen Warren Cc: Marek Vasut --- Changes in v3: None Changes in v2: - Make this change unconditional - Add Tested-by from Stephen common/usb.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) diff --git a/common/usb.c b/common/usb.c index c7b8b0e..45a5a0f 100644 --- a/common/usb.c +++ b/common/usb.c @@ -919,19 +919,8 @@ __weak int usb_alloc_device(struct usb_device *udev) static int usb_hub_port_reset(struct usb_device *dev, struct usb_device *hub) { - if (hub) { - unsigned short portstatus; - int err; - - /* reset the port for the second time */ - err = legacy_hub_port_reset(hub, dev->portnr - 1, &portstatus); - if (err < 0) { - printf("\n Couldn't reset port %i\n", dev->portnr); - return err; - } - } else { + if (!hub) usb_reset_root_port(dev); - } return 0; } -- 2.7.3