Re: [PATCH v8 0/7] i2c: Add FSI-attached I2C master algorithm

From: Andy Shevchenko
Date: Wed May 30 2018 - 17:31:52 EST


On Thu, May 31, 2018 at 12:07 AM, Eddie James
<eajames@xxxxxxxxxxxxxxxxxx> wrote:
> This series adds an algorithm for an I2C master physically located on an FSI
> slave device. The I2C master has multiple ports, each of which may be connected
> to an I2C slave. Access to the I2C master registers is achieved over FSI bus.
>
> Due to the multi-port nature of the I2C master, the driver instantiates a new
> I2C adapter for each port connected to a slave. The connected ports should be
> defined in the device tree under the I2C master device.

I'll comment the series later, though you have to address previous
comments first:
- understand devm_ purpose and how it works
- understand list_for_each*() macros
- discuss with maintainer a design of enumerating ports
- ... (whatever I forgot and others added) ...

> Changes since v7
> - Fix grammer in Kconfig (a -> an)
> - Change I2C registers to use BIT and GENMASK
> - Remove custom macros and use FIELD_PREP and FIELD_GET
> - Fix a few unecessary initializations and "return rc" that are always zero
> - Clean up the read/write fifo functions a bit
> - Few other clean-up items
>
> Changes since v6
> - Remove spinlock for reset functionality; it's unecessary and doesn't work
> with the latest FSI core.
> - Use a mutex instead of a semaphore, and don't wait for timeout to get the
> lock.
> - Use usleeps instead of schedule_timeout; it's not worth the overhead when
> the wait should be very short in between sending the command and receiving
> the response.
>
> Changes since v5
> - Fix reset functionality and do a reset after every transfer failure
>
> Eddie James (7):
> dt-bindings: i2c: Add FSI-attached I2C master dt binding documentation
> i2c: Add FSI-attached I2C master algorithm
> i2c: fsi: Add port structures
> i2c: fsi: Add abort and hardware reset procedures
> i2c: fsi: Add transfer implementation
> i2c: fsi: Add I2C master locking
> i2c: fsi: Add bus recovery
>
> Documentation/devicetree/bindings/i2c/i2c-fsi.txt | 40 ++
> drivers/i2c/busses/Kconfig | 11 +
> drivers/i2c/busses/Makefile | 1 +
> drivers/i2c/busses/i2c-fsi.c | 722 ++++++++++++++++++++++
> 4 files changed, 774 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-fsi.txt
> create mode 100644 drivers/i2c/busses/i2c-fsi.c
>
> --
> 1.8.3.1
>



--
With Best Regards,
Andy Shevchenko