Messages in this thread | | | Date | Wed, 26 Jul 2023 12:54:36 +0200 | From | Uwe Kleine-König <> | Subject | Re: [PATCH -next] drm/bridge: fix -Wunused-const-variable= warning |
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[Cc += Arnd, Andy who did similar changes in the past]
Hello,
On Wed, Jul 26, 2023 at 06:06:26PM +0800, Zhu Wang wrote: > When building with W=1, the following warning occurs. > > drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c:48:17: warning: ‘anx781x_i2c_addresses’ defined but not used [-Wunused-const-variable=] > static const u8 anx781x_i2c_addresses[] = { > ^~~~~~~~~~~~~~~~~~~~~ > drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c:40:17: warning: ‘anx7808_i2c_addresses’ defined but not used [-Wunused-const-variable=] > static const u8 anx7808_i2c_addresses[] = { > > The definition of above two data variables is included by the > macro CONFIG_OF, so we also include the data variable > definitions in the macro CONFIG_OF. And in addition the data > variable anx78xx_match_table is included in the macro CONFIG_OF, > so we add CONFIG_OF to the place where it is used. > > Fixes: 5d97408e0d70 ("drm/bridge: move ANA78xx driver to analogix subdirectory") > > Signed-off-by: Zhu Wang <wangzhu9@huawei.com> > --- > drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c > index 06a3e3243e19..799b33cebdd5 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c > @@ -37,6 +37,7 @@ > > #define XTAL_CLK 270 /* 27M */ > > +#if IS_ENABLED(CONFIG_OF) > static const u8 anx7808_i2c_addresses[] = { > [I2C_IDX_TX_P0] = 0x78, > [I2C_IDX_TX_P1] = 0x7a, > @@ -52,6 +53,7 @@ static const u8 anx781x_i2c_addresses[] = { > [I2C_IDX_RX_P0] = 0x7e, > [I2C_IDX_RX_P1] = 0x80, > }; > +#endif
You can mark anx7808_i2c_addresses with __maybe_unused, then the #if isn't needed.
> struct anx78xx_platform_data { > struct regulator *dvdd10; > @@ -1387,7 +1389,9 @@ MODULE_DEVICE_TABLE(of, anx78xx_match_table); > static struct i2c_driver anx78xx_driver = { > .driver = { > .name = "anx7814", > +#if IS_ENABLED(CONFIG_OF) > .of_match_table = of_match_ptr(anx78xx_match_table), > +#endif
If CONFIG_OF is disabled of_match_ptr(something) evaluates to NULL, so you can drop the #if here.
Having said that the better fix is probably to just do
.of_match_table = anx78xx_match_table,
as systems using ACPI can benefit from the of_match_table, too. See b89a9e9890d4 ("gpio: aggregator: Remove CONFIG_OF and of_match_ptr() protections") for an example.
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ | [unhandled content-type:application/pgp-signature] | |