[PATCH v5 00/19] staging: r8188eu: Shorten and simplify calls chain

[Fabio M. De Francesco]

io_ops abstraction is useless in this driver, since there is only one ops
registration. Without io_ops we can get rid of indirect calls mess and
shorten the calls chain.

Shorten the calls chain of rtw_read8/16/32() down to the actual reads.
For this purpose unify the three usb_read8/16/32 into the new
usb_read(); make the latter parameterizable with 'size'; embed most of
the code of usbctrl_vendorreq() into usb_read() and use in it the new
usb_control_msg_recv() API of USB Core.

Shorten the calls chain of rtw_write8/16/32() down to the actual writes.
For this purpose unify the four usb_write8/16/32/N() into the new
usb_write(); make the latter parameterizable with 'size'; embed most of
the code of usbctrl_vendorreq() into usb_write() and use in it the new
usb_control_msg_send() API of USB Core.

The code with the modifications was thoroughly tested by Pavel Skripkin
using a TP-Link TL-WN722N v2 / v3 [Realtek RTL8188EUS] and by Fabio M.
De Francesco using a ASUSTek Computer, Inc. Realtek 8188EUS [USB-N10 Nano].

Changelog:

v4->v5:
        - 1-14:
                No changes;
        - 15-16:
                Fix minor formatting issues and use "Reverse Xmas Tree" style,
                according to suggestions by David Laight and Dan Carpenter;
        - 17-18:
                Pavel Skripkin found logical errors in the checks of the
                values returned by usb_control_msg_{recv,send}(), so fix them;
                Dan Carpenter suggested to do error handling before success
                handling, so change the code accordingly;
        - 19:
                Add this patch in order to get rid of the shared buffer in
                usb_read() and usb_write() and remove this field from struct
                "dvobj_priv".

v3->v4:
        - 1-14:
                Split a patch into fourteen;
        - 15-16:
                Add these patches for clean-ups of the code that is going to be
                reused in 17-18/18;
        - 17-18:
                Make some changes according to a first review of Greg
                Kroah-Hartman; furthermore, remove the unnecessary while loop
                and a couple of if' test; handle the errors returned by
                usb_control_msg_recv().

v2->v3:
        - 1:
                No changes;
        - 3:
                Fix the version number of the patch.

v1->v2:
        - 1:
                No changes;
        - 3:
                Replace parameter REALTEK_USB_VENQT_READ with REALTEK_USB_VENQT_WRITE
                in usb_control_msg_send(). More in-depth explanation at
                https://lore.kernel.org/lkml/2791328.7pjKATJfGa@localhost.localdomain/T/#m1fc1ab2f7c1f463049ad88d5df5bb1b107b37260

v1: https://lore.kernel.org/lkml/20210904150447.14659-1-fmdefrancesco@xxxxxxxxx/
v2: https://lore.kernel.org/lkml/20210904212719.11426-1-fmdefrancesco@xxxxxxxxx/
v3: https://lore.kernel.org/lkml/20210904220048.12822-1-fmdefrancesco@xxxxxxxxx/
v4: https://lore.kernel.org/lkml/20210913181002.16651-1-fmdefrancesco@xxxxxxxxx/

Fabio M. De Francesco (4):
  staging: r8188eu: hal: Clean up usbctrl_vendorreq()
  staging: r8188eu: hal: Clean up rtw_read*() and rtw_write*()
  staging: r8188eu: Shorten calls chain of rtw_read8/16/32()
  staging: r8188eu: Shorten calls chain of rtw_write8/16/32/N()

Pavel Skripkin (15):
  staging: r8188eu: remove usb_{read,write}_mem
  staging: r8188eu: remove the helpers of rtw_read8()
  staging: r8188eu: remove the helpers of rtw_read16()
  staging: r8188eu: remove the helpers of rtw_read32()
  staging: r8188eu: remove the helpers of usb_write8
  staging: r8188eu: remove the helpers of usb_write16
  staging: r8188eu: remove the helpers of usb_write32
  staging: r8188eu: remove the helpers of usb_writeN
  staging: r8188eu: remove the helpers of usb_read_port
  staging: r8188eu: remove the helpers of usb_write_port
  staging: r8188eu: remove the helpers of usb_read_port_cancel
  staging: r8188eu: remove the helpers of usb_write_port_cancel
  staging: r8188eu: remove core/rtw_io.c
  staging: remove struct _io_ops
  staging: r8188eu: remove shared buffer for usb requests

 drivers/staging/r8188eu/Makefile              |   1 -
 drivers/staging/r8188eu/core/rtw_io.c         | 299 ------------------
 drivers/staging/r8188eu/hal/usb_halinit.c     |   6 +-
 drivers/staging/r8188eu/hal/usb_ops_linux.c   | 261 ++++++++-------
 drivers/staging/r8188eu/include/drv_types.h   |   5 -
 drivers/staging/r8188eu/include/rtw_io.h      |  89 +-----
 drivers/staging/r8188eu/include/usb_ops.h     |   2 -
 .../staging/r8188eu/include/usb_ops_linux.h   |   8 -
 drivers/staging/r8188eu/os_dep/usb_intf.c     |  37 +--
 .../staging/r8188eu/os_dep/usb_ops_linux.c    |  20 +-
 10 files changed, 166 insertions(+), 562 deletions(-)
 delete mode 100644 drivers/staging/r8188eu/core/rtw_io.c

-- 
2.33.0