Re: [RFC 10/32] i2c: Kconfig: add HAS_IOPORT dependencies

On Tue, 2021-12-28 at 11:21 +0100, Geert Uytterhoeven wrote:

Hi Niklas,

On Mon, Dec 27, 2021 at 5:49 PM Niklas Schnelle [off-list ref] wrote:

quoted

In a future patch HAS_IOPORT=n will result in inb()/outb() and friends
not being declared. We thus need to add HAS_IOPORT as dependency for
those drivers using them.

Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>

Thanks for your patch!

quoted

--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig

@@ -828,6 +828,7 @@ config I2C_NPCM7XX

 config I2C_OCORES
        tristate "OpenCores I2C Controller"
+       depends on HAS_IOPORT

While drivers/i2c/busses/i2c-ocores.c does use {in,out}(), I doubt this
is used to access legacy I/O space.

Hmm, it does use i2c->iobase for inb()/outb() but i2c->base for
ioreadXY()/iowriteXY(). And as it gets i2c->iobase from
platform_get_resource(pdev, IORESOURCE_IO, 0) I'd think that is an I/O
resource/space. It does look like some kind of fallback path though,
the IORESOURCE_IO is only looked at if accessing an IORESOURCE_MEM
fails so maybe that should instead be ifdeffed.

quoted

        help
          If you say yes to this option, support will be included for the
          OpenCores I2C controller. For details see

@@ -1227,6 +1228,7 @@ config I2C_CP2615
 config I2C_PARPORT
        tristate "Parallel port adapter"
        depends on PARPORT
+       depends on HAS_IOPORT

Same as PRINTER: shouldn't this work with all parport drivers?

Agree, will drop.

quoted

        select I2C_ALGOBIT
        select I2C_SMBUS
        help

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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