[PATCH v1] platform/chrome: cros_ec_proto: allow to build as module

[PATCH v1] platform/chrome: cros_ec_proto: allow to build as module

[Slawomir Rosek]

This allows to build ChromeOS EC communication protocol helpers as
kernel module which is particularly useful for Android GKI (Generic
Kernel Image) configuration. With this change the ChromeOS Platform
(CONFIG_CHROME_PLATFORMS=y) can be enabled directly from the vendor
kconfig fragment whithout additional configuration in gki_defconfig.

Signed-off-by: Slawomir Rosek <srosek@chromium.org>
---
 drivers/platform/chrome/Kconfig         | 2 +-
 drivers/platform/chrome/Makefile        | 3 ++-
 drivers/platform/chrome/cros_ec_proto.c | 3 +++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 1b2f2bd09662..f523ae3d3be0 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -155,7 +155,7 @@ config CROS_EC_LPC
 	  module will be called cros_ec_lpcs.
 
 config CROS_EC_PROTO
-	bool
+	tristate
 	help
 	  ChromeOS EC communication protocol helpers.
 
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 1a5a484563cc..b981a1bb5bd8 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -25,7 +25,8 @@ endif
 obj-$(CONFIG_CROS_EC_TYPEC)		+= cros-ec-typec.o
 
 obj-$(CONFIG_CROS_EC_LPC)		+= cros_ec_lpcs.o
-obj-$(CONFIG_CROS_EC_PROTO)		+= cros_ec_proto.o cros_ec_trace.o
+cros-ec-proto-objs			:= cros_ec_proto.o cros_ec_trace.o
+obj-$(CONFIG_CROS_EC_PROTO)		+= cros-ec-proto.o
 obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT)	+= cros_kbd_led_backlight.o
 obj-$(CONFIG_CROS_EC_CHARDEV)		+= cros_ec_chardev.o
 obj-$(CONFIG_CROS_EC_LIGHTBAR)		+= cros_ec_lightbar.o
diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 877b107fee4b..f90d2e7b616c 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -1157,3 +1157,6 @@ int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd)
 		return resp.version_mask;
 }
 EXPORT_SYMBOL_GPL(cros_ec_get_cmd_versions);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS EC communication protocol helpers");
-- 
2.49.0.472.ge94155a9ec-goog

Re: [PATCH v1] platform/chrome: cros_ec_proto: allow to build as module

[Tzung-Bi Shih]

On Fri, Mar 28, 2025 at 01:26:12PM +0000, Slawomir Rosek wrote:
> This allows to build ChromeOS EC communication protocol helpers as

s/This allows/Allow/.

> kernel module which is particularly useful for Android GKI (Generic
> Kernel Image) configuration. With this change the ChromeOS Platform
> (CONFIG_CHROME_PLATFORMS=y) can be enabled directly from the vendor
> kconfig fragment whithout additional configuration in gki_defconfig.

Does it work?  CROS_EC_PROTO is "selected" by other Kconfigs.  Wouldn't it
be either =y or =n?

Re: [PATCH v1] platform/chrome: cros_ec_proto: allow to build as module

[Sławomir Rosek]

On Wed, Apr 2, 2025 at 10:24 AM Tzung-Bi Shih <tzungbi@kernel.org> wrote:
>
> On Fri, Mar 28, 2025 at 01:26:12PM +0000, Slawomir Rosek wrote:
> > This allows to build ChromeOS EC communication protocol helpers as
>
> s/This allows/Allow/.

I will fix that, thanks.

>
> > kernel module which is particularly useful for Android GKI (Generic
> > Kernel Image) configuration. With this change the ChromeOS Platform
> > (CONFIG_CHROME_PLATFORMS=y) can be enabled directly from the vendor
> > kconfig fragment whithout additional configuration in gki_defconfig.
>
> Does it work?  CROS_EC_PROTO is "selected" by other Kconfigs.  Wouldn't it
> be either =y or =n?

Yes, it is already used by android 6.6 and 6.12 kernels. The
CROS_EC_PROTO is used only by other tristates so =m propagates
properly.

Re: [PATCH v1] platform/chrome: cros_ec_proto: allow to build as module

[Tzung-Bi Shih]

On Fri, Mar 28, 2025 at 01:26:12PM +0000, Slawomir Rosek wrote:
> This allows to build ChromeOS EC communication protocol helpers as
> kernel module which is particularly useful for Android GKI (Generic
> Kernel Image) configuration. With this change the ChromeOS Platform
> (CONFIG_CHROME_PLATFORMS=y) can be enabled directly from the vendor
> kconfig fragment whithout additional configuration in gki_defconfig.
> 
> [...]

Applied to

    https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next

[1/1] platform/chrome: cros_ec_proto: allow to build as module
      commit: ccf395bde6aeefac139f4f250287feb139e3355d

Thanks!