Re: [EXT] Re: [PATCH v4 03/11] media: dt-bindings: Add bindings for i.MX8QXP/QM JPEG driver

From: Mirela Rabulea
Date: Mon Nov 09 2020 - 16:59:45 EST


Hi,

On Wed, 2020-11-04 at 16:38 -0600, Rob Herring wrote:
> > +title: i.MX8QXP/QM JPEG decoder/encoder Device Tree Bindings
> > +
> > +maintainers:
> > + - Mirela Rabulea <mirela.rabulea@xxxxxxx>
> > +
> > +description: |-
> > + The JPEG decoder/encoder present in.MXQXP/QM SoC is an
> > + ISO/IEC 10918-1 JPEG standard compliant decoder/encoder, for
> > Baseline
> > + and Extended Sequential DCT modes.
> > +
> > +properties:
> > + compatible:
> > + items:
> > + - enum:
> > + # JPEG decoder
> > + - fsl,imx8-jpgdec
> > + # JPEG encoder
> > + - fsl,imx8-jpgenc
>
> Which imx8? Should be SoC specific.

This IP is present in 2 SOCs, imx8qxp & imx8qm.
For the next version, I modified the compatibles to nxp,imx8qxp-jpgdec
& nxp,imx8qxp-jpgenc, since only 8qxp was tested upstream.
I kept the name of the yaml file generic, but modified it to nxp,imx8-
jpeg.yaml. Possibly, in the future, this file will also host imx8qm
compatibles.
Also changed the dtb & driver accordingly.

>
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + interrupts:
> > + description: |
> > + There are 4 slots available in the IP
> > + If a certain slot is used, it should have an associated
> > interrupt
> > + minItems: 1 # At least one slot should be
> > available
> > + maxItems: 4 # The IP has 4 slots available for
> > use
>
> You don't need to know which slot is available?

No, the driver keeps track of which slots are used (and, for now, only
uses slot 0).
It is also possible to determine which is the current running slot by
accessing a status memory mapped register (the IP runs the configured
slots in a round-robin manner, not in parallel).
The assumption is, however, that in the device node, the interrupt i is
for slot i. So, I rephrased this to:
interrupts:
description: |
There are 4 slots available in the IP, which the driver may use
If a certain slot is used, it should have an associated interrupt
The interrupt with index i is assumed to be for slot i
minItems: 1 # At least one slot is needed by the
driver
maxItems: 4 # The IP has 4 slots available for use


Thanks,
Mirela