[v3,0/3] i3c dw,ast2600: Add a driver for the AST2600 i3c controller

This series adds a new i3c controller driver, for the ASPEED AST2600 i3c
SoC peripheral. This device is very similar to the dw i3c controller, so
we implement this by adding a little platform abstraction to the dw
driver, and then a platform implementation for ast2600.

For those testing at home: there's a couple of prereqs for getting this
running: we need the ast2600 i3c clocks in their proper configuration,
as implemented in:

  https://lore.kernel.org/all/20230302005834.13171-1-jk@codeconstruct.com.au/

- this series has been merged to clk-next, but has not hit Linus'
upstream yet. The series will still build fine without this.

You'll also want the dts definitions for the i3c controller and
pincontrol setup on the ast2600 platform. I have changes for those in my
dev/i3c branch:

  https://github.com/CodeConstruct/linux/commits/dev/i3c

- and will send those once we have the driver accepted.

v3: expand the prereqs & background above, and implement some feedback
from review. Mainly: rather that using a platform_data pointer, assume
platforms will use an encapsulating struct for their platform-specific
data

v2: This is a rework from an earlier series that implemented this as
part of the dw driver; I have adopted Ben Dooks' suggestion to split
into a new driver + exported hooks from the dw base.

As always: comments, queries etc. are most welcome.

Cheers,


Jeremy

Jeremy Kerr (3):
  i3c: dw: Add infrastructure for platform-specific implementations
  dt-bindings: i3c: Add AST2600 i3c controller
  i3c: ast2600: Add AST2600 platform-specific driver

 .../bindings/i3c/aspeed,ast2600-i3c.yaml      |  72 ++++++++
 MAINTAINERS                                   |   6 +
 drivers/i3c/master/Kconfig                    |  14 ++
 drivers/i3c/master/Makefile                   |   1 +
 drivers/i3c/master/ast2600-i3c-master.c       | 168 ++++++++++++++++++
 drivers/i3c/master/dw-i3c-master.c            |  76 ++++----
 drivers/i3c/master/dw-i3c-master.h            |  54 ++++++
 7 files changed, 358 insertions(+), 33 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/i3c/aspeed,ast2600-i3c.yaml
 create mode 100644 drivers/i3c/master/ast2600-i3c-master.c
 create mode 100644 drivers/i3c/master/dw-i3c-master.h

Hi Lukwinski,

> > +	case 545:
> > +		reg = AST2600_I3CG_REG0_SDA_PULLUP_EN_2K |
> > +			AST2600_I3CG_REG0_SDA_PULLUP_EN_750;
>
> It does not work. To enable PullUp=545R you need to set both 28 and
> 29 bit (0x30000000) but 'AST2600_I3CG_REG0_SDA_PULLUP_EN_2K |
> AST2600_I3CG_REG0_SDA_PULLUP_EN_750' is in fact 0x20000000.

Ah, good catch - I'd missed that the 2K is 0b00.

> Maybe you could consider adding extra macro
> 'AST2600_I3CG_REG0_SDA_PULLUP_EN_545' = (0x3 << 28)?

Sounds good, I'll send a fix today.

Cheers,


Jeremy