Re: [PATCH v2 0/5] video: udlfb: (not only) Logging cleanup

On Monday, January 08, 2018 05:55:27 PM Ladislav Michl wrote:

On Thu, Jan 04, 2018 at 08:36:23PM +0100, Ladislav Michl wrote:

quoted

This patchset is a side product of debugging on unreliable USB host
where devices saw a lot of disconnects. It turned out that udlfb
logging is just too noisy to be usefull as produced syslog is hard
to read.

Hence this attempt to clean things up.

Comments and suggestions welcome and appreciated, as always.

Changes in v2:
- Dropped patch "Delete error messages for failed allocations"
- Dropped patch "Remove unnecessary 'return'"
- Added patch "Remove noisy warnings"
- Reordered patches
- Rebased against next-20180104
  Please note as kernel compilation fails with:
    kernel/exit.o: In function `__crc_abort':
    exit.c:(*ABS*+0xc0e2ec8b): multiple definition of `__crc_abort'
    Makefile:1029: recipe for target 'vmlinux' failed
  this patchset is not runtime tested.

FYI, now runtime tested with next-20180108:

usb 2-1.4.1: new high-speed USB device number 6 using ehci-omap
usb 2-1.4.1: New USB device found, idVendor=058f, idProduct=6254
usb 2-1.4.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
hub 2-1.4.1:1.0: USB hub found
hub 2-1.4.1:1.0: 4 ports detected
usb 2-1.4.1.2: new high-speed USB device number 7 using ehci-omap
usb 2-1.4.1.2: New USB device found, idVendor=17e9, idProduct=401a
usb 2-1.4.1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 2-1.4.1.2: Product: mimo
usb 2-1.4.1.2: Manufacturer: DisplayLink
usb 2-1.4.1.2: SerialNumber: 7090902
udlfb 2-1.4.1.2:1.0: vendor descriptor length:23 data:23 5f 01 00 21 00 04 04 07 00 01
udlfb 2-1.4.1.2:1.0: DL chip limited to 1500000 pixel modes
usb 2-1.4.1.2: fb1 is DisplayLink USB device (800x480, 1504K framebuffer memory)

quoted

Ladislav Michl (5):
  video: udlfb: Remove unnecessary local variable
  video: udlfb: Remove redundant gdev variable
  video: udlfb: Remove noisy warnings
  video: udlfb: Do not name private data 'dev'

I queued patches #1-4 for v4.16, thanks.

quoted

  video: udlfb: Switch from the pr_*() to the dev_*() logging functions

This one introduces new compile time warning:

drivers/video/fbdev/udlfb.c: In function ‘dlfb_init_framebuffer_work’:
drivers/video/fbdev/udlfb.c:1694:24: warning: ignoring return value of ‘device_create_bin_file’, declared with attribute warn_unused_result [-Wunused-result]
  device_create_bin_file(info->dev, &edid_attr);
                        ^

Checking of device_create_bin_file()'s return value should not be removed,

[ ditto for device_create_file() ]

Also please fix the new comment introduced by the patch:

+               /* parent device is used otherwise*/

[  ...e*/ -> ...e */ ]

quoted

 drivers/video/fbdev/udlfb.c | 635 +++++++++++++++++++++-----------------------
 include/video/udlfb.h       |   3 +-
 2 files changed, 302 insertions(+), 336 deletions(-)

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics