I've broken up the previous patch for adding tt downstream scheduling into
7 patches. Here's the first.
This simply adds think_time to the usb_tt struct and sets it appropriately
(measured in ns).
Signed-off-by: Dan Streetman <[EMAIL PROTECTED]>
diff -urpN a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
--- a/drivers/usb/core/hub.c 2005-07-15 17:18:57.000000000 -0400
+++ b/drivers/usb/core/hub.c 2005-08-03 12:15:32.000000000 -0400
@@ -610,19 +610,29 @@ static int hub_configure(struct usb_hub
break;
}
+ /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
- case 0x00:
- if (hdev->descriptor.bDeviceProtocol != 0)
- dev_dbg(hub_dev, "TT requires at most 8 FS bit
times\n");
+ case HUB_TTTT_8_BITS:
+ if (hdev->descriptor.bDeviceProtocol != 0) {
+ hub->tt.think_time = 666;
+ dev_dbg(hub_dev, "TT requires at most 8 FS bit
times (%d ns)\n",
+ hub->tt.think_time);
+ }
break;
- case 0x20:
- dev_dbg(hub_dev, "TT requires at most 16 FS bit
times\n");
+ case HUB_TTTT_16_BITS:
+ hub->tt.think_time = 666 * 2;
+ dev_dbg(hub_dev, "TT requires at most 16 FS bit times
(%d ns)\n",
+ hub->tt.think_time);
break;
- case 0x40:
- dev_dbg(hub_dev, "TT requires at most 24 FS bit
times\n");
+ case HUB_TTTT_24_BITS:
+ hub->tt.think_time = 666 * 3;
+ dev_dbg(hub_dev, "TT requires at most 24 FS bit times
(%d ns)\n",
+ hub->tt.think_time);
break;
- case 0x60:
- dev_dbg(hub_dev, "TT requires at most 32 FS bit
times\n");
+ case HUB_TTTT_32_BITS:
+ hub->tt.think_time = 666 * 4;
+ dev_dbg(hub_dev, "TT requires at most 32 FS bit times
(%d ns)\n",
+ hub->tt.think_time);
break;
}
diff -urpN a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
--- a/drivers/usb/core/hub.h 2005-07-15 17:18:57.000000000 -0400
+++ b/drivers/usb/core/hub.h 2005-08-03 12:15:32.000000000 -0400
@@ -157,6 +157,12 @@ enum hub_led_mode {
struct usb_device;
+/* Transaction Translator Think Times, in bits */
+#define HUB_TTTT_8_BITS 0x00
+#define HUB_TTTT_16_BITS 0x20
+#define HUB_TTTT_24_BITS 0x40
+#define HUB_TTTT_32_BITS 0x60
+
/*
* As of USB 2.0, full/low speed devices are segregated into trees.
* One type grows from USB 1.1 host controllers (OHCI, UHCI etc).
@@ -170,6 +176,7 @@ struct usb_device;
struct usb_tt {
struct usb_device *hub; /* upstream highspeed hub */
int multi; /* true means one TT per port */
+ int think_time; /* transation translator think
time in ns */
/* for control/bulk error recovery (CLEAR_TT_BUFFER) */
spinlock_t lock;
-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
linux-usb-devel@lists.sourceforge.net
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
