[PATCH v3 0/5] sunxi: fix H6 HDMI related issues

Jernej Skrabec jernej.skrabec at siol.net
Tue Feb 9 12:58:55 EST 2021

Over the year I got plenty of reports of troubles with H6 HDMI signal.
Sometimes monitor flickers, sometimes there was no image at all and
sometimes it didn't play well with AVR.

It turns out there are multiple issues. Patch 1 fixes clock issue,
which didn't adjust parent rate, even if it is allowed to do so. Patch 2
adds polarity config in tcon1. This is seemingly not needed for pre-HDMI2
controllers, although BSP drivers set it accordingly every time. It
turns out that HDMI2 controllers often don't work with monitors if
polarity is not set correctly. Patch 3 always set clock rate for HDMI
controller. Patch 4 fixes H6 HDMI PHY settings. Patch 5 fixes comment and
clock rate limit (wrong reasoning).

Please take a look.

Best regards,

Changes from v2:
- use clk_hw_can_set_rate_parent() directly instead of checking flags
Changes from v1:
- collected Chen-Yu tags (except on replaced patch 4)
- Added some comments in patch 2
- Replaced patch 4 (see commit log for explanation)

Jernej Skrabec (5):
  clk: sunxi-ng: mp: fix parent rate change flag check
  drm/sun4i: tcon: set sync polarity for tcon1 channel
  drm/sun4i: dw-hdmi: always set clock rate
  drm/sun4i: Fix H6 HDMI PHY configuration
  drm/sun4i: dw-hdmi: Fix max. frequency for H6

 drivers/clk/sunxi-ng/ccu_mp.c          |  2 +-
 drivers/gpu/drm/sun4i/sun4i_tcon.c     | 25 +++++++++++++++++++++++++
 drivers/gpu/drm/sun4i/sun4i_tcon.h     |  6 ++++++
 drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c  | 10 +++-------
 drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h  |  1 -
 drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c | 26 +++++++++-----------------
 6 files changed, 44 insertions(+), 26 deletions(-)


More information about the linux-arm-kernel mailing list