[lkml]   [2019]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 2/8] fbdev: sm712fb: fix brightness control on reboot, don't set SR30.
On Sun, Mar 17, 2019 at 06:24:58AM +0800, Yifeng Li wrote:
> On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), rebooting with
> sm712fb framebuffer driver would cause the role of brightness up/down
> button to swap.
> Experiments showed the FPR30 register caused this behavior. Moreover,
> even if this register don't have side-effect on other systems, over-
> writing it is also highly questionable, since it was originally
> configurated by the motherboard manufacturer by hardwiring pull-down
> resistors to indicate the type of LCD panel. We should not mess with
> it.
> Stop writing to the SR30 (a.k.a FPR30) register.
> Signed-off-by: Yifeng Li <>
> Cc: # v4.4+

Tested-by: Sudip Mukherjee <>


 \ /
  Last update: 2019-03-31 14:20    [W:0.126 / U:0.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site