Re: [PATCH v2 20/28] drm/i2c: tda998x: move the TBG_CNTRL_0register setting

From: Jean-Francois Moine
Date: Sun Jan 12 2014 - 08:21:14 EST

On Sun, 12 Jan 2014 12:31:59 +0000
Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote:

> > So, in my patch 9, I was writing the REG_TBG_CNTRL_1 after writing
> > REG_TBG_CNTRL_0, and you refused it. Here, I write REG_TBG_CNTRL_0
> > after the write of REG_TBG_CNTRL_1 in the HDMI sequence, and you still
> > don't agree.
> >
> > What is the right way?
> No, both NAKS are for the exact same issue.
> Patch 9 inserted the write to REG_TBG_CNTRL_1 after REG_TBG_CNTRL_0.
> Then in this patch you move REG_TBG_CNTRL_0 after all writes.
> Had you appropriately placed the write to REG_TBG_CNTRL_1 in patch 9
> in the first place, _this_ patch (patch 20) would not be required to
> then move REG_TBG_CNTRL_0 after it. So, fixing patch 9 removes the
> need for patch 20.

Fixing the patch 9 gives:

* Always generate sync polarity relative to input sync and
* revert input stage toggled sync at output stage
if (adj_mode->flags & DRM_MODE_FLAG_NHSYNC)
reg |= TBG_CNTRL_1_H_TGL;
if (adj_mode->flags & DRM_MODE_FLAG_NVSYNC)
reg |= TBG_CNTRL_1_V_TGL;
reg_write(priv, REG_TBG_CNTRL_1, reg);

/* must be last register set: */
reg_clear(priv, REG_TBG_CNTRL_0, TBG_CNTRL_0_SYNC_ONCE);

/* Only setup the info frames if the sink is HDMI */
if (priv->is_hdmi_sink) {
/* We need to turn HDMI HDCP stuff on to get audio through */
reg_write(priv, REG_TBG_CNTRL_1, reg);
reg_write(priv, REG_ENC_CNTRL, ENC_CNTRL_CTL_CODE(1));
reg_set(priv, REG_TX33, TX33_HDMI);

tda998x_write_avi(priv, adj_mode);

if (priv->params.audio_cfg)
tda998x_configure_audio(priv, adj_mode, &priv->params);

and REG_TBG_CNTRL_1 is set in the HDMI branch (with REG_ENC_CNTRL and

Is this OK?

Ken ar c'hentaà | ** Breizh ha Linux atav! **
Jef |
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