2019-03-04 20:08:23

by Arnd Bergmann

Subject: [PATCH] platform/chrome: fix wilco-ec dependencies

When CROS_EC_LPC is set to =m, we get a link failure for a
builtin wilco-ec module:

drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_remove':
core.c:(.text+0x26): undefined reference to `cros_ec_lpc_mec_destroy'
drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_probe':
core.c:(.text+0x18c): undefined reference to `cros_ec_lpc_mec_init'
core.c:(.text+0x224): undefined reference to `cros_ec_lpc_mec_destroy'
drivers/platform/chrome/wilco_ec/mailbox.o: In function `wilco_ec_mailbox':
mailbox.c:(.text+0x104): undefined reference to `cros_ec_lpc_io_bytes_mec'

The problem with the existing CROS_EC_LPC_MEC dependency is that this
is only for a 'bool' symbol, so the information about the exported
functions being in a module is lost on the way, and we actually have
to depend on both CROS_EC_LPC and CROS_EC_LPC_MEC.

Fixes: 7b3d4f44abf0 ("platform/chrome: Add new driver for Wilco EC")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/platform/chrome/wilco_ec/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig
index 4a119ced4d0c..e09e4cebe9b4 100644
--- a/drivers/platform/chrome/wilco_ec/Kconfig
+++ b/drivers/platform/chrome/wilco_ec/Kconfig
@@ -1,6 +1,6 @@
config WILCO_EC
tristate "ChromeOS Wilco Embedded Controller"
- depends on ACPI && X86 && CROS_EC_LPC_MEC
+ depends on ACPI && X86 && CROS_EC_LPC && CROS_EC_LPC_MEC
help
If you say Y here, you get support for talking to the ChromeOS
Wilco EC over an eSPI bus. This uses a simple byte-level protocol
--
2.20.0

2019-03-05 00:55:25

by Nick Crews

Subject: Re: [PATCH] platform/chrome: fix wilco-ec dependencies

On Mon, Mar 4, 2019 at 1:06 PM Arnd Bergmann <[email protected]> wrote:
>
> When CROS_EC_LPC is set to =m, we get a link failure for a
> builtin wilco-ec module:
>
> drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_remove':
> core.c:(.text+0x26): undefined reference to `cros_ec_lpc_mec_destroy'
> drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_probe':
> core.c:(.text+0x18c): undefined reference to `cros_ec_lpc_mec_init'
> core.c:(.text+0x224): undefined reference to `cros_ec_lpc_mec_destroy'
> drivers/platform/chrome/wilco_ec/mailbox.o: In function `wilco_ec_mailbox':
> mailbox.c:(.text+0x104): undefined reference to `cros_ec_lpc_io_bytes_mec'
>
> The problem with the existing CROS_EC_LPC_MEC dependency is that this
> is only for a 'bool' symbol, so the information about the exported
> functions being in a module is lost on the way, and we actually have
> to depend on both CROS_EC_LPC and CROS_EC_LPC_MEC.

Thanks for the catch Arnd. This looks like a workable solution, although it
brings up a different question to me: Is it weird for a bool option
(such as CROS_EC_LPC_MEC)
to depend upon a tristate option (such as CROS_EC_LPC)? It seems like
CROS_EC_LPC_MEC
should be tristate as well. Would changing this be a better solution?

>
> Fixes: 7b3d4f44abf0 ("platform/chrome: Add new driver for Wilco EC")
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> drivers/platform/chrome/wilco_ec/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig
> index 4a119ced4d0c..e09e4cebe9b4 100644
> --- a/drivers/platform/chrome/wilco_ec/Kconfig
> +++ b/drivers/platform/chrome/wilco_ec/Kconfig
> @@ -1,6 +1,6 @@
> config WILCO_EC
> tristate "ChromeOS Wilco Embedded Controller"
> - depends on ACPI && X86 && CROS_EC_LPC_MEC
> + depends on ACPI && X86 && CROS_EC_LPC && CROS_EC_LPC_MEC
> help
> If you say Y here, you get support for talking to the ChromeOS
> Wilco EC over an eSPI bus. This uses a simple byte-level protocol
> --
> 2.20.0
>

2019-03-05 08:28:10

by Arnd Bergmann

Subject: Re: [PATCH] platform/chrome: fix wilco-ec dependencies

On Tue, Mar 5, 2019 at 1:53 AM Nick Crews <[email protected]> wrote:
>
> On Mon, Mar 4, 2019 at 1:06 PM Arnd Bergmann <[email protected]> wrote:
> >
> > When CROS_EC_LPC is set to =m, we get a link failure for a
> > builtin wilco-ec module:
> >
> > drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_remove':
> > core.c:(.text+0x26): undefined reference to `cros_ec_lpc_mec_destroy'
> > drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_probe':
> > core.c:(.text+0x18c): undefined reference to `cros_ec_lpc_mec_init'
> > core.c:(.text+0x224): undefined reference to `cros_ec_lpc_mec_destroy'
> > drivers/platform/chrome/wilco_ec/mailbox.o: In function `wilco_ec_mailbox':
> > mailbox.c:(.text+0x104): undefined reference to `cros_ec_lpc_io_bytes_mec'
> >
> > The problem with the existing CROS_EC_LPC_MEC dependency is that this
> > is only for a 'bool' symbol, so the information about the exported
> > functions being in a module is lost on the way, and we actually have
> > to depend on both CROS_EC_LPC and CROS_EC_LPC_MEC.
>
> Thanks for the catch Arnd. This looks like a workable solution, although it
> brings up a different question to me: Is it weird for a bool option
> (such as CROS_EC_LPC_MEC)
> to depend upon a tristate option (such as CROS_EC_LPC)?

No, not weird at all.

> It seems like
> CROS_EC_LPC_MEC
> should be tristate as well. Would changing this be a better solution?

No, that would actually break the code in a different way, since you
have:

drivers/platform/chrome/Makefile:cros_ec_lpcs-$(CONFIG_CROS_EC_LPC_MEC)
+= cros_ec_lpc_mec.o
drivers/platform/chrome/cros_ec_lpc_reg.c:#ifdef CONFIG_CROS_EC_LPC_MEC
drivers/platform/chrome/cros_ec_lpc_reg.c:#else /* CONFIG_CROS_EC_LPC_MEC */
drivers/platform/chrome/cros_ec_lpc_reg.c:#endif /* CONFIG_CROS_EC_LPC_MEC */

With CONFIG_CROS_EC_LPC_MEC=m, it would not get used
(CONFIG_CROS_EC_LPC_MEC ends up not defined in C code),
and it makes no sense to include a .o file in a loadable module
based on a tristate option.

Arnd

2019-03-05 13:00:45

by Enric Balletbo i Serra

Subject: Re: [PATCH] platform/chrome: fix wilco-ec dependencies

Hi,

On 4/3/19 21:06, Arnd Bergmann wrote:
> When CROS_EC_LPC is set to =m, we get a link failure for a
> builtin wilco-ec module:
>
> drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_remove':
> core.c:(.text+0x26): undefined reference to `cros_ec_lpc_mec_destroy'
> drivers/platform/chrome/wilco_ec/core.o: In function `wilco_ec_probe':
> core.c:(.text+0x18c): undefined reference to `cros_ec_lpc_mec_init'
> core.c:(.text+0x224): undefined reference to `cros_ec_lpc_mec_destroy'
> drivers/platform/chrome/wilco_ec/mailbox.o: In function `wilco_ec_mailbox':
> mailbox.c:(.text+0x104): undefined reference to `cros_ec_lpc_io_bytes_mec'
>
> The problem with the existing CROS_EC_LPC_MEC dependency is that this
> is only for a 'bool' symbol, so the information about the exported
> functions being in a module is lost on the way, and we actually have
> to depend on both CROS_EC_LPC and CROS_EC_LPC_MEC.
>
> Fixes: 7b3d4f44abf0 ("platform/chrome: Add new driver for Wilco EC")
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> drivers/platform/chrome/wilco_ec/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig
> index 4a119ced4d0c..e09e4cebe9b4 100644
> --- a/drivers/platform/chrome/wilco_ec/Kconfig
> +++ b/drivers/platform/chrome/wilco_ec/Kconfig
> @@ -1,6 +1,6 @@
> config WILCO_EC
> tristate "ChromeOS Wilco Embedded Controller"
> - depends on ACPI && X86 && CROS_EC_LPC_MEC
> + depends on ACPI && X86 && CROS_EC_LPC && CROS_EC_LPC_MEC
> help
> If you say Y here, you get support for talking to the ChromeOS
> Wilco EC over an eSPI bus. This uses a simple byte-level protocol
>

Applied as a fix to our chrome-platform-5.1 branch.

Thanks,
Enric