[U-Boot] [PATCH 2/2] usb: Do not power-cycle usb devices on init
Hans de Goede
hdegoede at redhat.com
Sat Sep 20 17:03:53 CEST 2014
Do as the Linux kernel does and power on any ports which are not yet one,
this is enough.
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
common/usb_hub.c | 39 ---------------------------------------
1 file changed, 39 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c
index c416e5e..0f1eab4 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -86,50 +86,11 @@ static void usb_hub_power_on(struct usb_hub_device *hub)
int i;
struct usb_device *dev;
unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
- ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
- unsigned short portstatus;
- int ret;
dev = hub->pusb_dev;
- /*
- * Enable power to the ports:
- * Here we Power-cycle the ports: aka,
- * turning them off and turning on again.
- */
debug("enabling power on all ports\n");
for (i = 0; i < dev->maxchild; i++) {
- usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
- debug("port %d returns %lX\n", i + 1, dev->status);
- }
-
- /* Wait at least 2*bPwrOn2PwrGood for PP to change */
- mdelay(pgood_delay);
-
- for (i = 0; i < dev->maxchild; i++) {
- ret = usb_get_port_status(dev, i + 1, portsts);
- if (ret < 0) {
- debug("port %d: get_port_status failed\n", i + 1);
- continue;
- }
-
- /*
- * Check to confirm the state of Port Power:
- * xHCI says "After modifying PP, s/w shall read
- * PP and confirm that it has reached the desired state
- * before modifying it again, undefined behavior may occur
- * if this procedure is not followed".
- * EHCI doesn't say anything like this, but no harm in keeping
- * this.
- */
- portstatus = le16_to_cpu(portsts->wPortStatus);
- if (portstatus & (USB_PORT_STAT_POWER << 1)) {
- debug("port %d: Port power change failed\n", i + 1);
- continue;
- }
- }
-
- for (i = 0; i < dev->maxchild; i++) {
usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
debug("port %d returns %lX\n", i + 1, dev->status);
}
--
2.1.0
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