Re: [PATCH 03/10] phy: Add MIPI D-PHY configuration options

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Maxime,

On Friday, 7 September 2018 11:56:23 EEST Maxime Ripard wrote:
> On Wed, Sep 05, 2018 at 04:43:57PM +0300, Laurent Pinchart wrote:
> >> The current set of parameters should cover all the potential users.
> >> 
> >> Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
> >> ---
> >> 
> >>  include/linux/phy/phy-mipi-dphy.h | 241 ++++++++++++++++++++++++++++++-
> >>  include/linux/phy/phy.h           |   6 +-
> >>  2 files changed, 247 insertions(+)
> >>  create mode 100644 include/linux/phy/phy-mipi-dphy.h
> >> 
> >> diff --git a/include/linux/phy/phy-mipi-dphy.h
> >> b/include/linux/phy/phy-mipi-dphy.h new file mode 100644
> >> index 000000000000..792724145290
> >> --- /dev/null
> >> +++ b/include/linux/phy/phy-mipi-dphy.h
> >> @@ -0,0 +1,241 @@
> >> +/* SPDX-License-Identifier: GPL-2.0 */
> >> +/*
> >> + * Copyright (C) 2018 Cadence Design Systems Inc.
> >> + */
> >> +
> >> +#ifndef __PHY_MIPI_DPHY_H_
> >> +#define __PHY_MIPI_DPHY_H_
> >> +
> >> +#include <video/videomode.h>
> >> +
> >> +/**
> >> + * struct phy_configure_opts_mipi_dphy - MIPI D-PHY configuration set
> >> + *
> >> + * This structure is used to represent the configuration state of a
> >> + * MIPI D-PHY phy.
> > 
> > Shouldn't we split the RX and TX parameters in two structures ?
> 
> Are they different? As far as I understood it, both were having the
> same parameters.

clk_miss, for instance, is a receiver parameter, while clk_post is a 
transmitter parameter. There are relationships between the transmitter and 
receiver parameters in the sense that they have to be compatible, and we may 
want to compute one set of parameters based on the other one, but I think they 
target RX and TX separately.

> >> +	/**
> >> +	 * @modes:
> >> +	 *
> >> +	 * transmission operation mode flags
> >> +	 */
> >> +	u32			modes;
> > 
> > Where are those flags defined ?
> 
> goto label;
> 
> >> +	/**
> >> +	 * @timings:
> >> +	 *
> >> +	 * Video timings associated with the transmission.
> > 
> > That's a pretty vague description...
> 
> I'll try to improve it then
> 
> >> +	 */
> >> +	struct videomode	timings;
> >> +};
> >> +
> 
> label:
> > > +/* TODO: Add other modes (burst, commands, etc) */
> > > +#define MIPI_DPHY_MODE_VIDEO_SYNC_PULSE		BIT(0)
> 
> But maybe I should reorganize it to make it more obvious.

-- 
Regards,

Laurent Pinchart