[RFC 2/4] mfd: add Gateworks System Controller core driver

Tim Harvey
2018-02-28T21:14:00Z

On Tue, Feb 27, 2018 at 6:00 PM, Randy Dunlap <rdunlap@infradead.org> wrote:
> On 02/27/2018 05:21 PM, Tim Harvey wrote:
>> The Gateworks System Controller (GSC) is an I2C slave controller
>> implemented with an MSP430 micro-controller whose firmware embeds the
>> following features:
>> - I/O expander (16 GPIO's) using PCA955x protocol
>> - Real Time Clock using DS1672 protocol
>> - User EEPROM using AT24 protocol
>> - HWMON using custom protocol
>> - Interrupt controller with tamper detect, user pushbotton
>> - Watchdog controller capable of full board power-cycle
>> - Power Control capable of full board power-cycle
>>
>> see http://trac.gateworks.com/wiki/gsc for more details
>>
>> Signed-off-by: Tim Harvey <tharvey@gateworks.com>
>> ---
>> drivers/mfd/Kconfig | 10 ++
>> drivers/mfd/Makefile | 1 +
>> drivers/mfd/gsc.c | 330 ++++++++++++++++++++++++++++++++++++++++++++++++
>> include/linux/mfd/gsc.h | 79 ++++++++++++
>> 4 files changed, 420 insertions(+)
>> create mode 100644 drivers/mfd/gsc.c
>> create mode 100644 include/linux/mfd/gsc.h
>>
>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
>> index 1d20a80..16dd486 100644
>> --- a/drivers/mfd/Kconfig
>> +++ b/drivers/mfd/Kconfig
>> @@ -341,6 +341,16 @@ config MFD_EXYNOS_LPASS
>> Select this option to enable support for Samsung Exynos Low Power
>> Audio Subsystem.
>>
>> +config MFD_GSC
>> + tristate "Gateworks System Controller"
>> + depends on (I2C && OF) || COMPILE_TEST
>
> Do both I2C and OF have stubs so that a driver will build when they are
> both disabled? I.e., only COMPILE_TEST is enabled?

Randy,

No, at this point it requires both I2C and OF. I may add platform data
to support an older non-device-tree family of boards but it still
would require I2C.

I will remove the || COMPILE_TEST

Thanks for catching that.

Tim