[PATCH 1/1] platform/x86: apple-gmux: don't use be32_to_cpu and cpu_to_be32

[PATCH 1/1] platform/x86: apple-gmux: don't use be32_to_cpu and cpu_to_be32

[Orlando Chamberlain]

Sparce doesn't seem to like using be32_to_cpu and cpu_to_be32 to convert
values for the MMIO gmux to/from the host architecture.

Instead use iowrite32be and ioread32be to always convert, which should be
fine because apple-gmux is only used on x86 with is always little endian.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202305161712.5l3f4iI4-lkp@intel.com/
Signed-off-by: Orlando Chamberlain <orlandoch.dev@gmail.com>
---
 drivers/platform/x86/apple-gmux.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index e02b4aea4f1e..cadbb557a108 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -278,7 +278,7 @@ static u32 gmux_mmio_read32(struct apple_gmux_data *gmux_data, int port)
 	iowrite8(GMUX_MMIO_READ | sizeof(val),
 		gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND);
 	gmux_mmio_wait(gmux_data);
-	val = be32_to_cpu(ioread32(gmux_data->iomem_base));
+	val = ioread32be(gmux_data->iomem_base);
 	mutex_unlock(&gmux_data->index_lock);
 
 	return val;
@@ -288,7 +288,7 @@ static void gmux_mmio_write32(struct apple_gmux_data *gmux_data, int port,
 			       u32 val)
 {
 	mutex_lock(&gmux_data->index_lock);
-	iowrite32(cpu_to_be32(val), gmux_data->iomem_base);
+	iowrite32be(val, gmux_data->iomem_base);
 	iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT);
 	iowrite8(GMUX_MMIO_WRITE | sizeof(val),
 		gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND);
-- 
2.41.0

Re: [PATCH 1/1] platform/x86: apple-gmux: don't use be32_to_cpu and cpu_to_be32

[Hans de Goede]

Hi,

On 6/14/23 08:49, Orlando Chamberlain wrote:
> Sparce doesn't seem to like using be32_to_cpu and cpu_to_be32 to convert
> values for the MMIO gmux to/from the host architecture.
> 
> Instead use iowrite32be and ioread32be to always convert, which should be
> fine because apple-gmux is only used on x86 with is always little endian.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202305161712.5l3f4iI4-lkp@intel.com/
> Signed-off-by: Orlando Chamberlain <orlandoch.dev@gmail.com>

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans



> ---
>  drivers/platform/x86/apple-gmux.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
> index e02b4aea4f1e..cadbb557a108 100644
> --- a/drivers/platform/x86/apple-gmux.c
> +++ b/drivers/platform/x86/apple-gmux.c
> @@ -278,7 +278,7 @@ static u32 gmux_mmio_read32(struct apple_gmux_data *gmux_data, int port)
>  	iowrite8(GMUX_MMIO_READ | sizeof(val),
>  		gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND);
>  	gmux_mmio_wait(gmux_data);
> -	val = be32_to_cpu(ioread32(gmux_data->iomem_base));
> +	val = ioread32be(gmux_data->iomem_base);
>  	mutex_unlock(&gmux_data->index_lock);
>  
>  	return val;
> @@ -288,7 +288,7 @@ static void gmux_mmio_write32(struct apple_gmux_data *gmux_data, int port,
>  			       u32 val)
>  {
>  	mutex_lock(&gmux_data->index_lock);
> -	iowrite32(cpu_to_be32(val), gmux_data->iomem_base);
> +	iowrite32be(val, gmux_data->iomem_base);
>  	iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT);
>  	iowrite8(GMUX_MMIO_WRITE | sizeof(val),
>  		gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND);