[PATCH] x86/olpc: select GPIOLIB_LEGACY

[PATCH] x86/olpc: select GPIOLIB_LEGACY

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

The OLPC GPIO controller sets up a fixed number space that is used
by at least two drivers:

arch/x86/platform/olpc/olpc-xo1-sci.c: In function 'setup_ec_sci':
arch/x86/platform/olpc/olpc-xo1-sci.c:358:13: error: implicit declaration of function 'gpio_request' [-Wimplicit-function-declaration]
  358 |         r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
      |             ^~~~~~~~~~~~
sound/pci/cs5535audio/cs5535audio_olpc.c: In function 'olpc_analog_input':
sound/pci/cs5535audio/cs5535audio_olpc.c:41:9: error: implicit declaration of function 'gpio_set_value'; did you mean 'gpiod_set_value'? [-Wimplicit-function-declaration]
   41 |         gpio_set_value(OLPC_GPIO_MIC_AC, on);

Select CONFIG_GPIOLIB_LEGACY for this platform and make sure the
sound driver portion cannot be compiled without this.

Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/x86/Kconfig  | 1 +
 sound/pci/Kconfig | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f3f7cb01d69d..5ada2c108f4a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -3022,6 +3022,7 @@ config OLPC
 	bool "One Laptop Per Child support"
 	depends on !X86_PAE
 	select GPIOLIB
+	select GPIOLIB_LEGACY
 	select OF
 	select OF_PROMTREE
 	select IRQ_DOMAIN
diff --git a/sound/pci/Kconfig b/sound/pci/Kconfig
index e0996a9d90b0..6366f72b3667 100644
--- a/sound/pci/Kconfig
+++ b/sound/pci/Kconfig
@@ -300,6 +300,7 @@ config SND_CS5535AUDIO
 	tristate "CS5535/CS5536 Audio"
 	depends on X86_32 || MIPS || COMPILE_TEST
 	depends on HAS_IOPORT
+	depends on GPIOLIB_LEGACY || !OLPC
 	select SND_PCM
 	select SND_AC97_CODEC
 	help
-- 
2.39.5

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Linus Walleij]

On Mon, Apr 27, 2026 at 4:43 PM Arnd Bergmann <arnd@kernel.org> wrote:

> From: Arnd Bergmann <arnd@arndb.de>
>
> The OLPC GPIO controller sets up a fixed number space that is used
> by at least two drivers:
>
> arch/x86/platform/olpc/olpc-xo1-sci.c: In function 'setup_ec_sci':
> arch/x86/platform/olpc/olpc-xo1-sci.c:358:13: error: implicit declaration of function 'gpio_request' [-Wimplicit-function-declaration]
>   358 |         r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
>       |             ^~~~~~~~~~~~
> sound/pci/cs5535audio/cs5535audio_olpc.c: In function 'olpc_analog_input':
> sound/pci/cs5535audio/cs5535audio_olpc.c:41:9: error: implicit declaration of function 'gpio_set_value'; did you mean 'gpiod_set_value'? [-Wimplicit-function-declaration]
>    41 |         gpio_set_value(OLPC_GPIO_MIC_AC, on);
>
> Select CONFIG_GPIOLIB_LEGACY for this platform and make sure the
> sound driver portion cannot be compiled without this.
>
> Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Linus Walleij <linusw@kernel.org>

I started to try to fix up this driver but it's such a mess. I feel
the OLPC XO1 support needs to be deleted unless someone
steps up to actually test and maintain it.

Yours,
Linus Walleij

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Arnd Bergmann]

On Mon, Apr 27, 2026, at 22:13, Linus Walleij wrote:
> On Mon, Apr 27, 2026 at 4:43 PM Arnd Bergmann <arnd@kernel.org> wrote:
>> Select CONFIG_GPIOLIB_LEGACY for this platform and make sure the
>> sound driver portion cannot be compiled without this.
>>
>> Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>
> Reviewed-by: Linus Walleij <linusw@kernel.org>
>
> I started to try to fix up this driver but it's such a mess. I feel
> the OLPC XO1 support needs to be deleted unless someone
> steps up to actually test and maintain it.

I understand where you're coming from: the machine was certainly
never really nice and was already quite underpowered 20 years ago,
Pretty much any distro that used to support it has stopped
years ago.

On the other hand, even the XO-1 was widely shipped to both users
and developers, super durable, and influential. There are a handful
of other upstream board files for the SCx200/Geode family, but this
is probably the most common one by far.

I see that the display controller driver (olpc_dcon) was removed
two years ago after being broken for years. It was first
removed in 2016 but restored immediately as there were still
users at the time.

I've added Andres Salomon, James Cameron and Lubomir Rintel
to Cc, they may have more information about who is still using
XO-1, and if anyone is still updating kernels.

       Arnd

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Linus Walleij]

On Tue, Apr 28, 2026 at 3:57 PM Arnd Bergmann <arnd@arndb.de> wrote:

> On the other hand, even the XO-1 was widely shipped to both users
> and developers, super durable, and influential. There are a handful
> of other upstream board files for the SCx200/Geode family, but this
> is probably the most common one by far.
>
> I see that the display controller driver (olpc_dcon) was removed
> two years ago after being broken for years. It was first
> removed in 2016 but restored immediately as there were still
> users at the time.

I looked at the removed driver
commit 214c2754fb0af78fde9faa2e5f9693c4618f3d5b
"staging: olpc_dcon: Remove driver marked as broken since 2022"

This is a simple driver and would *not* be hard to rewrite
using the DRM helpers that exist today, by just looking at other
simple DRM drivers such as drivers/gpu/drm/tve200/*.

So if there is interest full upstream support should not be
hard to attain. But it requires some dedication, and I wonder
if such exist.

Yours,
Linus Walleij

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Andres Salomon]

On 4/28/26 18:34, Linus Walleij wrote:
> On Tue, Apr 28, 2026 at 3:57 PM Arnd Bergmann <arnd@arndb.de> wrote:
> 
>> On the other hand, even the XO-1 was widely shipped to both users
>> and developers, super durable, and influential. There are a handful
>> of other upstream board files for the SCx200/Geode family, but this
>> is probably the most common one by far.
>>
>> I see that the display controller driver (olpc_dcon) was removed
>> two years ago after being broken for years. It was first
>> removed in 2016 but restored immediately as there were still
>> users at the time.
> 
> I looked at the removed driver
> commit 214c2754fb0af78fde9faa2e5f9693c4618f3d5b
> "staging: olpc_dcon: Remove driver marked as broken since 2022"
> 
> This is a simple driver and would *not* be hard to rewrite
> using the DRM helpers that exist today, by just looking at other
> simple DRM drivers such as drivers/gpu/drm/tve200/*.
> 
> So if there is interest full upstream support should not be
> hard to attain. But it requires some dedication, and I wonder
> if such exist.
> 
> Yours,
> Linus Walleij

I can't speak for other (former) OLPC folks, but I donated my remaining 
OLPC hardware about seven years ago; so I no longer have any interest or 
ability to support the hardware.

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Arnd Bergmann]

On Wed, Apr 29, 2026, at 00:39, Andres Salomon wrote:
> On 4/28/26 18:34, Linus Walleij wrote:
>> On Tue, Apr 28, 2026 at 3:57 PM Arnd Bergmann <arnd@arndb.de> wrote:
>> 
>>> On the other hand, even the XO-1 was widely shipped to both users
>>> and developers, super durable, and influential. There are a handful
>>> of other upstream board files for the SCx200/Geode family, but this
>>> is probably the most common one by far.
>>>
>>> I see that the display controller driver (olpc_dcon) was removed
>>> two years ago after being broken for years. It was first
>>> removed in 2016 but restored immediately as there were still
>>> users at the time.
>> 
>> I looked at the removed driver
>> commit 214c2754fb0af78fde9faa2e5f9693c4618f3d5b
>> "staging: olpc_dcon: Remove driver marked as broken since 2022"
>> 
>> This is a simple driver and would *not* be hard to rewrite
>> using the DRM helpers that exist today, by just looking at other
>> simple DRM drivers such as drivers/gpu/drm/tve200/*.
>> 
>> So if there is interest full upstream support should not be
>> hard to attain. But it requires some dedication, and I wonder
>> if such exist.

It looks like Lubomir actually did that work already and
submitted a proper driver a few years ago, at least for the
XO-1.75:
https://lists.freedesktop.org/archives/dri-devel/2018-December/201019.html

This was never merged, but it's there in case someone wants
to continue where he left off. As far as I can tell, the staging
driver was used with the XO-1 and XO-1.5, while this one was
for XO-1.75, but the actual chip is the same and the driver is
almost portable.

> I can't speak for other (former) OLPC folks, but I donated my remaining 
> OLPC hardware about seven years ago; so I no longer have any interest or 
> ability to support the hardware.

I see you are still listed as paid support for AMD Geode in the
MAINTAINERS file. Is that still the case, or did that end along
with your involvement in XO-1?

Are you aware of any Geode users that still update their kernels?
I found that OpenWRT still publishes Geode builds (with XO-1
disabled, but everything else built in) but no indication that
anyone has actually run these after around 2017.

      Arnd

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Andres Salomon]

On 4/29/26 16:39, Arnd Bergmann wrote:
> On Wed, Apr 29, 2026, at 00:39, Andres Salomon wrote:
>> On 4/28/26 18:34, Linus Walleij wrote:
>>> On Tue, Apr 28, 2026 at 3:57 PM Arnd Bergmann <arnd@arndb.de> wrote:
[...]
> 
>> I can't speak for other (former) OLPC folks, but I donated my remaining
>> OLPC hardware about seven years ago; so I no longer have any interest or
>> ability to support the hardware.
> 
> I see you are still listed as paid support for AMD Geode in the
> MAINTAINERS file. Is that still the case, or did that end along
> with your involvement in XO-1?
> 

No, my involvement with anything Geode and OLPC ended years ago. Feel 
free to remove me from MAINTAINERS (unless someone has specific 
questions about hardware, which I'm happy to answer).


> Are you aware of any Geode users that still update their kernels?
> I found that OpenWRT still publishes Geode builds (with XO-1
> disabled, but everything else built in) but no indication that
> anyone has actually run these after around 2017.
> 
>        Arnd

Personally I don't know anyone, but I feel like those Geode thin clients 
are more likely to still be in use. A machine with 256MB of ram in 2026 
is going to be an absolutely miserable laptop to use, but that's still 
fine for a limited router or wifi access point. If you remove/disable 
the Geode stuff, you probably won't hear complaints until the next major 
OpenWRT release, though.

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[James Cameron]

On Wed, Apr 29, 2026 at 12:34:53AM +0200, Linus Walleij wrote:
> So if there is interest full upstream support should not be
> hard to attain. But it requires some dedication, and I wonder
> if such exist.

I'm still here, keeping infrastructure running, still have hardware,
still receive telemetry showing children using our Fedora 18 build
(!), and still answering technical questions.

But we don't have funding for this kind of work.  We now buy-in
laptops.

It would be wonderful if keeping dcon happens, but I have to be
realistic; whoever does it will need to be very dedicated to acquire
second-hand hardware and work through the various other things that
stop the modern kernel from running on it.  I'll cheer you on if
that's you, and may even help out by mail, but I've other funded work,
so my time is limited.

Good luck!

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Takashi Iwai]

On Mon, 27 Apr 2026 16:43:05 +0200,
Arnd Bergmann wrote:
> 
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The OLPC GPIO controller sets up a fixed number space that is used
> by at least two drivers:
> 
> arch/x86/platform/olpc/olpc-xo1-sci.c: In function 'setup_ec_sci':
> arch/x86/platform/olpc/olpc-xo1-sci.c:358:13: error: implicit declaration of function 'gpio_request' [-Wimplicit-function-declaration]
>   358 |         r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
>       |             ^~~~~~~~~~~~
> sound/pci/cs5535audio/cs5535audio_olpc.c: In function 'olpc_analog_input':
> sound/pci/cs5535audio/cs5535audio_olpc.c:41:9: error: implicit declaration of function 'gpio_set_value'; did you mean 'gpiod_set_value'? [-Wimplicit-function-declaration]
>    41 |         gpio_set_value(OLPC_GPIO_MIC_AC, on);
> 
> Select CONFIG_GPIOLIB_LEGACY for this platform and make sure the
> sound driver portion cannot be compiled without this.
> 
> Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  arch/x86/Kconfig  | 1 +
>  sound/pci/Kconfig | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index f3f7cb01d69d..5ada2c108f4a 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -3022,6 +3022,7 @@ config OLPC
>  	bool "One Laptop Per Child support"
>  	depends on !X86_PAE
>  	select GPIOLIB
> +	select GPIOLIB_LEGACY
>  	select OF
>  	select OF_PROMTREE
>  	select IRQ_DOMAIN
> diff --git a/sound/pci/Kconfig b/sound/pci/Kconfig
> index e0996a9d90b0..6366f72b3667 100644
> --- a/sound/pci/Kconfig
> +++ b/sound/pci/Kconfig
> @@ -300,6 +300,7 @@ config SND_CS5535AUDIO
>  	tristate "CS5535/CS5536 Audio"
>  	depends on X86_32 || MIPS || COMPILE_TEST
>  	depends on HAS_IOPORT
> +	depends on GPIOLIB_LEGACY || !OLPC
>  	select SND_PCM
>  	select SND_AC97_CODEC
>  	help

Acked-by: Takashi Iwai <tiwai@suse.de>


thanks,

Takashi

Re: [PATCH] x86/olpc: select GPIOLIB_LEGACY

[Bartosz Golaszewski]

On Mon, 27 Apr 2026 16:43:05 +0200, Arnd Bergmann <arnd@kernel.org> said:
> From: Arnd Bergmann <arnd@arndb.de>
>
> The OLPC GPIO controller sets up a fixed number space that is used
> by at least two drivers:
>
> arch/x86/platform/olpc/olpc-xo1-sci.c: In function 'setup_ec_sci':
> arch/x86/platform/olpc/olpc-xo1-sci.c:358:13: error: implicit declaration of function 'gpio_request' [-Wimplicit-function-declaration]
>   358 |         r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
>       |             ^~~~~~~~~~~~
> sound/pci/cs5535audio/cs5535audio_olpc.c: In function 'olpc_analog_input':
> sound/pci/cs5535audio/cs5535audio_olpc.c:41:9: error: implicit declaration of function 'gpio_set_value'; did you mean 'gpiod_set_value'? [-Wimplicit-function-declaration]
>    41 |         gpio_set_value(OLPC_GPIO_MIC_AC, on);
>
> Select CONFIG_GPIOLIB_LEGACY for this platform and make sure the
> sound driver portion cannot be compiled without this.
>
> Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>