[v3,0/2] i2c: stm32f7: add SMBus-Alert support

Message

Alain Volmat March 29, 2021, 6:09 a.m. UTC

This serie adds support for SMBus Alert on the STM32F7.
A new binding st,smbus-alert is added in order to differenciate
with the existing smbus binding.

SMBA alert control and status logic must be enabled along with
SMBALERT# pin configured via pinctrl in the device tree. This is the
rational for adding "st,smbus-alert" property.

---
v3:
use lore.kernel.org links instead of marc.info

v2:
When SMBUS alert isn't available on the board (SMBA unused), this
logic musn't be enabled. Enabling it unconditionally wrongly lead to get
SMBA interrupts.
So, add "st,smbus-alert" dedicated binding to have a smbus alert with a
consistent pin configuration in DT.

Alain Volmat (2):
  dt-bindings: i2c: stm32f7: add st,smbus-alert binding for SMBus Alert
  i2c: stm32f7: add SMBus-Alert support

 .../devicetree/bindings/i2c/st,stm32-i2c.yaml |  5 ++
 drivers/i2c/busses/i2c-stm32f7.c              | 73 +++++++++++++++++++
 2 files changed, 78 insertions(+)

Comments

Alain Volmat April 30, 2021, 4:44 p.m. UTC | #1

Hi Wolfram,

Gentle reminder about this serie about SMBus-Alert. Could you have
a look at it ?

Thanks
Alain

On Mon, Mar 29, 2021 at 08:09:03AM +0200, Alain Volmat wrote:
> This serie adds support for SMBus Alert on the STM32F7.
> A new binding st,smbus-alert is added in order to differenciate
> with the existing smbus binding.
> 
> SMBA alert control and status logic must be enabled along with
> SMBALERT# pin configured via pinctrl in the device tree. This is the
> rational for adding "st,smbus-alert" property.
> 
> ---
> v3:
> use lore.kernel.org links instead of marc.info
> 
> v2:
> When SMBUS alert isn't available on the board (SMBA unused), this
> logic musn't be enabled. Enabling it unconditionally wrongly lead to get
> SMBA interrupts.
> So, add "st,smbus-alert" dedicated binding to have a smbus alert with a
> consistent pin configuration in DT.
> 
> Alain Volmat (2):
>   dt-bindings: i2c: stm32f7: add st,smbus-alert binding for SMBus Alert
>   i2c: stm32f7: add SMBus-Alert support
> 
>  .../devicetree/bindings/i2c/st,stm32-i2c.yaml |  5 ++
>  drivers/i2c/busses/i2c-stm32f7.c              | 73 +++++++++++++++++++
>  2 files changed, 78 insertions(+)
> 
> -- 
> 2.17.1
>

Wolfram Sang May 4, 2021, 7:51 p.m. UTC | #2

> Gentle reminder about this serie about SMBus-Alert. Could you have
> a look at it ?

Yes. I first thought to do this after increasing SMBus Block length to
255. But because of the userspace ABI problems, it probably makes sense
to work on this first. Here, no userspace is involved.