Re: [PATCH 1/5] media: adv748x: Rework reset procedure

[jacopo mondi <jacopo@jmondi.org>]

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Hi Kieran,
   thanks for review

On Tue, Dec 11, 2018 at 11:52:03PM +0000, Kieran Bingham wrote:
> Hi Jacopo,
>
> On 11/12/2018 15:16, Jacopo Mondi wrote:
> > Re-work the chip reset procedure to configure the CP (HDMI) and SD (AFE) cores
> > before resetting the MIPI CSI-2 TXs.
> >
> > Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> > ---
> >  drivers/media/i2c/adv748x/adv748x-core.c | 24 ++++++++++--------------
> >  1 file changed, 10 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/media/i2c/adv748x/adv748x-core.c b/drivers/media/i2c/adv748x/adv748x-core.c
> > index d94c63cb6a2e..5495dc7891e8 100644
> > --- a/drivers/media/i2c/adv748x/adv748x-core.c
> > +++ b/drivers/media/i2c/adv748x/adv748x-core.c
> > @@ -353,9 +353,8 @@ static const struct adv748x_reg_value adv748x_sw_reset[] = {
> >  	{ADV748X_PAGE_EOR, 0xff, 0xff}	/* End of register table */
> >  };
> >
> > -/* Supported Formats For Script Below */
> > -/* - 01-29 HDMI to MIPI TxA CSI 4-Lane - RGB888: */
>
> Is this information redundant ? (CSI-4Lane, RGB888 configuration?)
>

The CSI-2 data lane configuration has been break out from this table
by Niklas' patches. I've tried also moving the format configuration
out of this, but I haven't sent that change. The HDMI video direction
is now handled at link setup time, so I guess the only relevant
information is about the RGB888 format configured on the CP backend.
I'll keep that.

> > -static const struct adv748x_reg_value adv748x_init_txa_4lane[] = {
> > +/* Initialize CP Core. */
> > +static const struct adv748x_reg_value adv748x_init_hdmi[] = {
>
> While we're here - is there much scope - or value in changing these
> tables to functions with parameters using Niklas' adv748x_write_check() ?
>
> The suggestion only has value if there are parameters that we would need
> to configure. So it might be reasonable to leave these tables.
>

Right now I don't see much value in that. I would prefer breaking out
the format configuration from this static tables, but that's for
later.

> A general Ack on renaming to the function instead of the
> TX/configuration though - as that makes the purpose clearer.
>
>
> >  	/* Disable chip powerdown & Enable HDMI Rx block */
> >  	{ADV748X_PAGE_IO, 0x00, 0x40},
> >
> > @@ -399,10 +398,8 @@ static const struct adv748x_reg_value adv748x_init_txa_4lane[] = {
> >  	{ADV748X_PAGE_EOR, 0xff, 0xff}	/* End of register table */
> >  };
> >
> > -/* 02-01 Analog CVBS to MIPI TX-B CSI 1-Lane - */
> > -/* Autodetect CVBS Single Ended In Ain 1 - MIPI Out */
> > -static const struct adv748x_reg_value adv748x_init_txb_1lane[] = {
> > -
>
> Same comments as above really :)
>

I'll see what I can keep.

Thanks
  j

> > +/* Initialize AFE core. */
> > +static const struct adv748x_reg_value adv748x_init_afe[] = {
> >  	{ADV748X_PAGE_IO, 0x00, 0x30},	/* Disable chip powerdown Rx */
> >  	{ADV748X_PAGE_IO, 0xf2, 0x01},	/* Enable I2C Read Auto-Increment */
> >
> > @@ -445,19 +442,18 @@ static int adv748x_reset(struct adv748x_state *state)
> >  	if (ret < 0)
> >  		return ret;
> >
> > -	/* Init and power down TXA */
> > -	ret = adv748x_write_regs(state, adv748x_init_txa_4lane);
> > +	/* Initialize CP and AFE cores. */
> > +	ret = adv748x_write_regs(state, adv748x_init_hdmi);
> >  	if (ret)
> >  		return ret;
> >
> > -	adv748x_tx_power(&state->txa, 1);
> > -	adv748x_tx_power(&state->txa, 0);
> > -
> > -	/* Init and power down TXB */
> > -	ret = adv748x_write_regs(state, adv748x_init_txb_1lane);
> > +	ret = adv748x_write_regs(state, adv748x_init_afe);
> >  	if (ret)
> >  		return ret;
> >
> > +	/* Reset TXA and TXB */
> > +	adv748x_tx_power(&state->txa, 1);
> > +	adv748x_tx_power(&state->txa, 0);
> >  	adv748x_tx_power(&state->txb, 1);
> >  	adv748x_tx_power(&state->txb, 0);
> >
> > --
> > 2.7.4
> >
>
> --
> Regards
> --
> Kieran

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