USB_PIPE_GET_MAX_BULK_TRANSFER_SIZE(9F) Kernel Functions for Drivers USB_PIPE_GET_MAX_BULK_TRANSFER_SIZE(9F)

usb_pipe_get_max_bulk_transfer_size - Get maximum bulk transfer size

#include <sys/usb/usba.h>
int usb_pipe_get_max_bulk_transfer_size(dev_info_t dip, size_t *size);

illumos DDI specific (illumos DDI)

dip
Pointer to the device's dev_info structure.

size

Returns the bulk transfer size.

The usb_pipe_get_max_bulk_transfer_size() function returns the maximum data transfer size in bytes that the host controller driver can support per bulk request. This information can be used to limit or break down larger requests to manageable sizes.

USB_SUCCESS
Size is returned in size argument.

USB_INVALID_ARGS

dip and/or size argument is NULL.

USB_FAILURE

Size could not be returned. Zero is returned in size arg.

May be called from user, kernel or interrupt context.


    int xxx_attach(dev_info_t *dip, int command)
    {
           ...
           usb_pipe_get_max_bulk_transfer_size(dip, &state>max_xfer_size);
           ...
    }
    void xxx_minphys(struct buf bp)
    {
           ...
           if (bp->b_bcount > state->max_xfer_size) {
                   bp->b_bcount = state->max_xfer_size;
           }
           ...
    }

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Architecture PCI-based systems
Interface stability Committed

attributes(5), usb_pipe_bulk_xfer(9F), usb_alloc_request(9F), usb_bulk_request(9S)
January 5, 2004 OmniOS