drm/rockchip: dsi: Reconfigure hardware on resume()
authorBrian Norris <briannorris@chromium.org>
Tue, 28 Sep 2021 21:35:50 +0000 (14:35 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 27 Jan 2022 10:03:03 +0000 (11:03 +0100)
commitf28d819f17d35a4ac603157dcbfaf20c16346bcb
tree7f05112c08596e1e225d42205afd9249b5e4802e
parent506bae94333b67d54f38d4021c2bbb32d8c58fa5
drm/rockchip: dsi: Reconfigure hardware on resume()

commit e584cdc1549932f87a2707b56bc588cfac5d89e0 upstream.

Since commit 43c2de1002d2 ("drm/rockchip: dsi: move all lane config except
LCDC mux to bind()"), we perform most HW configuration in the bind()
function. This configuration may be lost on suspend/resume, so we
need to call it again. That may lead to errors like this after system
suspend/resume:

  dw-mipi-dsi-rockchip ff968000.mipi: failed to write command FIFO
  panel-kingdisplay-kd097d04 ff960000.mipi.0: failed write init cmds: -110

Tested on Acer Chromebook Tab 10 (RK3399 Gru-Scarlet).

Note that early mailing list versions of this driver borrowed Rockchip's
downstream/BSP solution, to do HW configuration in mode_set() (which
*is* called at the appropriate pre-enable() times), but that was
discarded along the way. I've avoided that still, because mode_set()
documentation doesn't suggest this kind of purpose as far as I can tell.

Fixes: 43c2de1002d2 ("drm/rockchip: dsi: move all lane config except LCDC mux to bind()")
Cc: <stable@vger.kernel.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: NĂ­colas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210928143413.v3.2.I4e9d93aadb00b1ffc7d506e3186a25492bf0b732@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c