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w1: ds2490 USB setup fixes

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Calling usb_reset_configuration after usb_set_interface resets the
interface that was just selected, so call reset first.
Using alternative 3 greatly speeds the one wire search.
alt 0 or 1, 10ms int, 23.16 seconds
alt 2 or 3,  1ms int, 2.99 to 3.05 seconds

Use usb_interrupt_msg not usb_bulk_msg as it is an interrupt pipe
(bulk worked, it was just technically the wrong call).

Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
David Fries 2014-01-15 22:29:22 -06:00 committed by Greg Kroah-Hartman
parent f28c4e1f31
commit da78b7e74a
1 changed files with 17 additions and 11 deletions
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28
drivers/w1/masters/ds2490.c
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@ -252,7 +252,8 @@ static int ds_recv_status_nodump(struct ds_device *dev, struct ds_status *st,
memset(st, 0, sizeof(*st));
count = 0;
err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_STATUS]), buf, size, &count, 100);
err = usb_interrupt_msg(dev->udev, usb_rcvintpipe(dev->udev,
dev->ep[EP_STATUS]), buf, size, &count, 100);
if (err < 0) {
printk(KERN_ERR "Failed to read 1-wire data from 0x%x: err=%d.\n", dev->ep[EP_STATUS], err);
return err;
@ -917,7 +918,7 @@ static int ds_probe(struct usb_interface *intf,
struct usb_endpoint_descriptor *endpoint;
struct usb_host_interface *iface_desc;
struct ds_device *dev;
int i, err;
int i, err, alt;
dev = kmalloc(sizeof(struct ds_device), GFP_KERNEL);
if (!dev) {
@ -935,20 +936,25 @@ static int ds_probe(struct usb_interface *intf,
usb_set_intfdata(intf, dev);
err = usb_set_interface(dev->udev, intf->altsetting[0].desc.bInterfaceNumber, 3);
if (err) {
printk(KERN_ERR "Failed to set alternative setting 3 for %d interface: err=%d.\n",
intf->altsetting[0].desc.bInterfaceNumber, err);
goto err_out_clear;
}
err = usb_reset_configuration(dev->udev);
if (err) {
printk(KERN_ERR "Failed to reset configuration: err=%d.\n", err);
dev_err(&dev->udev->dev,
"Failed to reset configuration: err=%d.\n", err);
goto err_out_clear;
}
iface_desc = &intf->altsetting[0];
/* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
alt = 3;
err = usb_set_interface(dev->udev,
intf->altsetting[alt].desc.bInterfaceNumber, alt);
if (err) {
dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
"for %d interface: err=%d.\n", alt,
intf->altsetting[alt].desc.bInterfaceNumber, err);
goto err_out_clear;
}
iface_desc = &intf->altsetting[alt];
if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
printk(KERN_INFO "Num endpoints=%d. It is not DS9490R.\n", iface_desc->desc.bNumEndpoints);
err = -EINVAL;