Re: [PATCH 1/2] drm/adi: axi-hdmi-tx: Add support for AXI HDMI TX IP core

From: Sam Ravnborg
Date: Fri Oct 16 2020 - 10:55:06 EST


Hi Bogdan

On Mon, Oct 05, 2020 at 05:12:08PM +0300, Bogdan Togorean wrote:
> From: Lars-Peter Clausen <lars@xxxxxxxxxx>
>
> The AXI HDMI HDL driver is the driver for the HDL graphics core which is
> used on various FPGA designs. It's mostly used to interface with the
> ADV7511 driver on some Zynq boards (e.g. ZC702 & ZedBoard).
>
> Link: https://wiki.analog.com/resources/tools-software/linux-drivers/drm/hdl-axi-hdmi
> Link: https://wiki.analog.com/resources/fpga/docs/axi_hdmi_tx

Thanks for submitting the driver - a few high level comments after
browsing the driver:

- Use drmm_mode_config_init() to utilize new cleanup
- Look at other uses of drm_driver - there is macros that makes this
much simpler / smaller
- Use devm_drm_dev_alloc() to allocate axi_hdmi_tx_private
To do so embed drm_device in axi_hdmi_tx_private - which is the way to
do it today
- Do not use ddev->dev_private, it is deprecated
- Use dev_err_probe() when you risk to see a PROBE_DEFER
- In all include blocks sort the include alphabetically
- Use the new interface to drm_bridge_attach() - where display driver
creates the connector
- See if the Kconfig selects can be trimmed - the framebuffer releated
selects looks wrong (others get it wrong too)
- Check if you can use the simple encoder - see
drm_simple_encoder_init()

If this is a simple one plane, one crtc display driver then it should
use the drm_simple_* support. Or the changelog should explain why not.

We want the drivers as simple as we can - and they shall use as much of
the helper infrastructure as they can.

We continue to develop the helper infrastructure so it is expected that
there is some lacking behind as is the case here.

Sam