usb: ci_udc: call udc_disconnect() from ci_pullup()

ci_pullup()'s !is_on path contains a cut/paste copy of udc_disconnect().
Remove the duplication by simply calling udc_disconnect() instead.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
usb: ci_udc: fix freeing of ep0 req

ci_ep_alloc_request() avoids allocating multiple request objects for ep0
by keeping a record of the first req allocated for ep0, and always
returning that instead of allocating a new req. However, if this req is
ever freed, the record of the previous allocation is not cleared, so
ci_ep_alloc_request() will keep returning this stale pointer. Fix
ci_ep_free_request() to clear the record of the previous allocation.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
usb: ci_udc: fix probe error cleanup

If allocation of the ep0 req fails, clean up all the allocations that
were made in ci_udc_probe().

Signed-off-by: Stephen Warren <swarren@nvidia.com>
usb: ci_udc: clean up all allocations in unregister

usb_gadget_unregister_driver() is called to tear down the USB device mode
stack. Fix the driver to stop the USB HW (which causes any attached host
to notice the disappearance of the device), and free all allocations
(which obviously prevents memory leaks).

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: enable DFU too

Enable DFU protocol support (via the "dfu" command) on Tegra boards where
USB device/gadget mode is enabled.

This relies on a number of fixes to the ci_udc HW driver and DFU protocol
code.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
TEMP HACK: enable ext4 write for DFU testing
fs: fat: implement fat_size()

Add function fat_size() to allow code to query the size of a file before
reading it. This could be used to allocate an appropriately sized buffer,
or to set up a USB or network communication protocol to read the data in
chunks.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
fs: ext4: implement ext4fs_size()

Add function ext4fs_size() to allow code to query the size of a file
before reading it. This could be used to allocate an appropriately sized
buffer, or to set up a USB or network communication protocol to read the
data in chunks.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
dfu: fix some issues with reads/uploads

DFU read support appears to rely upon dfu->read_medium() updating the
passed-by-reference len parameter to indicate the remaining size
available for reading.

dfu_read_medium_mmc() never does this, and the implementation of
dfu_read_medium_nand() will only work if called just once; it hard-codes
the value to the total size of the NAND device irrespective of read
offset.

I believe that overloading dfu->read_medium() is confusing. As such,
this patch introduces a new function dfu->get_medium_size() which can
be used to explicitly find out the medium size, and nothing else.
dfu_read() is modified to use this function to set the initial value for
dfu->r_left, rather than attempting to use the side-effects of
dfu->read_medium() for this purpose.

Due to this change, dfu_read() must initially set dfu->b_left to 0, since
no data has been read.

dfu_read_buffer_fill() must also be modified not to adjust dfu->r_left
when simply copying data from dfu->i_buf_start to the upload request
buffer. r_left represents the amount of data left to be read from HW.
That value is not affected by the memcpy(), but only by calls to
dfu->read_medium().

After this change, I can read from either a 4MB or 1.5MB chunk of a 4MB
eMMC boot partion with CONFIG_SYS_DFU_DATA_BUF_SIZE==1MB. Without this
change, attempting to do that would result in DFU read returning no data
at all due to r_left never being set.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
---
v2: Fix dfu_get_medium_size_mmc() to handle DFU_FS_FAT/EXT5 layouts too.
test:dfu: Add test script for testing DFU regression

This commit adds test script for testing if any commit has introduced
regression to the DFU.

It uses md5 to test if sent and received file is correct.
The test detailed description is available at DESCRIPTION.TXT file.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
DFU test script hacks
fs: implement size/fatsize/ext4size

FIXME: Needs squashing etc.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
WIP: dfu: use new size command

... this sets up the FS block device first, so stands a better chance of
working...

Signed-off-by: Stephen Warren <swarren@nvidia.com>