pinctrl: mcp23s08: Fix probe issues

[PATCH v2 0/2] pinctrl: mcp23s08: Fix probe issues

Posted by Judith Mendez 4 weeks, 1 day ago

MCP23S18 driver probe failures on AM62L3 BeagleBadge[0].

Fix MCP23S18 probe failures found with BeagleBadge which has a MCP23S18
on board chip. Fixes are made up of initializing chip data before regmap
init, and using device_property_read_u8 to match binding spec. First fix
prevents kernel oops and second fix prevents MCP chip probe failure.

[0] https://github.com/beagleboard/BeagleBadge

Changes since v1:
- Add #define for base address & use instead of 0x40 hardcode base address
- Add patch 2/2

Judith Mendez (2):
  pinctrl: mcp23s08: Initialize mcp->dev and mcp->addr before regmap
    init
  pinctrl: mcp23s08: Read spi-present-mask as u8 not u32

 drivers/pinctrl/pinctrl-mcp23s08_spi.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

-- 
2.54.0

Re: [PATCH v2 0/2] pinctrl: mcp23s08: Fix probe issues

Posted by Linus Walleij 2 weeks, 6 days ago

On Thu, May 14, 2026 at 1:12 AM Judith Mendez <jm@ti.com> wrote:

> MCP23S18 driver probe failures on AM62L3 BeagleBadge[0].
>
> Fix MCP23S18 probe failures found with BeagleBadge which has a MCP23S18
> on board chip. Fixes are made up of initializing chip data before regmap
> init, and using device_property_read_u8 to match binding spec. First fix
> prevents kernel oops and second fix prevents MCP chip probe failure.
>
> [0] https://github.com/beagleboard/BeagleBadge

Patches applied for fixes!

Thanks for digging in and solving this.

Yours,
Linus Walleij