Subject: Re: [PATCH 0/3] Change ISA_BUS_API dependency to selection
To: William Breathitt Gray <vilhelm.gray@gmail.com>,
        linus.walleij@linaro.org
Cc: mail@maciej.szmigiero.name, linux-gpio@vger.kernel.org,
        linux-iio@vger.kernel.org, linux-watchdog@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <cover.1514475654.git.vilhelm.gray@gmail.com>
From: Guenter Roeck <linux@roeck-us.net>
Message-ID: <4339f82b-5f37-fb8d-2725-d45747608c2e@roeck-us.net>
Date: Thu, 28 Dec 2017 09:03:22 -0800
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On 12/28/2017 08:01 AM, William Breathitt Gray wrote:
> The ISA_BUS_API Kconfig option enables the compilation of the ISA bus
> driver. The ISA bus driver does not perform any hardware interaction,
> and is instead just a thin layer of software abstraction to eliminate
> boilerplate code common to ISA-style device drivers. Since ISA_BUS_API
> has no dependencies and does not jeopardize the integrity of the system
> when enabled, drivers should select it when the ISA bus driver
> functionality is needed.
> 
> Originally, when the ISA_BUS_API Kconfig option was introduced, it
> served a dual-purpose of masking drivers ISA-style devices not commonly
> found for desktop systems, such as the PC/104 device drivers. This
> secondary semantic was inappropriate for the ISA_BUS_API option, and
> proper masking of these device drivers is now accomplished via dedicated
> Kconfig options such as CONFIG_PC104.
> 
> Linus, please pickup this entire patchset through your GPIO subsystem
> tree; a recursive dependency error is present if these patches are
> cherry-picked (see https://lkml.org/lkml/2017/12/26/235), so they should
> be merged together in the same tree.
> 
> Maciej, this patchset resolves the recursive dependency issue you
> encountered, so now you should be able to submit your Winbond GPIO
> driver with the ISA_BUS_API selection as desired.
> 
> William Breathitt Gray (3):
>    iio: Change ISA_BUS_API dependency to selection
>    watchdog: Change ISA_BUS_API dependency to selection
>    gpio: Change ISA_BUS_API dependency to selection
> 
>   drivers/gpio/Kconfig        | 14 +++++++++-----
>   drivers/iio/adc/Kconfig     |  3 ++-
>   drivers/iio/counter/Kconfig |  3 ++-
>   drivers/iio/dac/Kconfig     |  3 ++-
>   drivers/watchdog/Kconfig    |  3 ++-
>   5 files changed, 17 insertions(+), 9 deletions(-)
> 
But why keep "config ISA_BUS" ? Its only purpose is to select ISA_BUS_API.

Guenter