[PATCH] power: supply: da9150-fg: remove VLA usage

[PATCH] power: supply: da9150-fg: remove VLA usage

[Gustavo A. R. Silva]

In preparation to enabling -Wvla, remove VLA usage and replace it
with fixed-length arrays.

It seems that the length of array 'buf' will not exceed
DA9150_QIF_SHORT_SIZE bytes (2 bytes). But a fixed length
of DA9150_QIF_BYTE_SIZE bytes (8 bytes) was chosen in case
this change in the future.

Fixed as part of the directive to remove all VLAs from
the kernel: https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/power/supply/da9150-fg.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/power/supply/da9150-fg.c b/drivers/power/supply/da9150-fg.c
index 8b8ce97..96893be 100644
--- a/drivers/power/supply/da9150-fg.c
+++ b/drivers/power/supply/da9150-fg.c
@@ -92,7 +92,7 @@ struct da9150_fg {
 static u32 da9150_fg_read_attr(struct da9150_fg *fg, u8 code, u8 size)
 
 {
-	u8 buf[size];
+	u8 buf[DA9150_QIF_BYTE_SIZE];
 	u8 read_addr;
 	u32 res = 0;
 	int i;
@@ -111,7 +111,7 @@ static void da9150_fg_write_attr(struct da9150_fg *fg, u8 code, u8 size,
 				 u32 val)
 
 {
-	u8 buf[size];
+	u8 buf[DA9150_QIF_BYTE_SIZE];
 	u8 write_addr;
 	int i;
 
-- 
2.7.4

RE: [PATCH] power: supply: da9150-fg: remove VLA usage

[Adam Thomson]

On 09 March 2018 04:58, Gustavo A. R. Silva wrote:

> In preparation to enabling -Wvla, remove VLA usage and replace it
> with fixed-length arrays.
> 
> It seems that the length of array 'buf' will not exceed
> DA9150_QIF_SHORT_SIZE bytes (2 bytes). But a fixed length
> of DA9150_QIF_BYTE_SIZE bytes (8 bytes) was chosen in case
> this change in the future.
> 
> Fixed as part of the directive to remove all VLAs from
> the kernel: https://lkml.org/lkml/2018/3/7/621
> 
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> ---
>  drivers/power/supply/da9150-fg.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/power/supply/da9150-fg.c b/drivers/power/supply/da9150-fg.c
> index 8b8ce97..96893be 100644
> --- a/drivers/power/supply/da9150-fg.c
> +++ b/drivers/power/supply/da9150-fg.c
> @@ -92,7 +92,7 @@ struct da9150_fg {
>  static u32 da9150_fg_read_attr(struct da9150_fg *fg, u8 code, u8 size)
> 
>  {
> -	u8 buf[size];
> +	u8 buf[DA9150_QIF_BYTE_SIZE];

You can use DA9150_QIF_LONG_SIZE as that's the biggest size of an attribute
which can be accessed. This will also save a little space.

>  	u8 read_addr;
>  	u32 res = 0;
>  	int i;
> @@ -111,7 +111,7 @@ static void da9150_fg_write_attr(struct da9150_fg *fg, u8
> code, u8 size,
>  				 u32 val)
> 
>  {
> -	u8 buf[size];
> +	u8 buf[DA9150_QIF_BYTE_SIZE];
>  	u8 write_addr;
>  	int i;
> 
> --
> 2.7.4

Re: [PATCH] power: supply: da9150-fg: remove VLA usage

[Gustavo A. R. Silva]

On 03/09/2018 05:36 AM, Adam Thomson wrote:
> On 09 March 2018 04:58, Gustavo A. R. Silva wrote:
> 
>> In preparation to enabling -Wvla, remove VLA usage and replace it
>> with fixed-length arrays.
>>
>> It seems that the length of array 'buf' will not exceed
>> DA9150_QIF_SHORT_SIZE bytes (2 bytes). But a fixed length
>> of DA9150_QIF_BYTE_SIZE bytes (8 bytes) was chosen in case
>> this change in the future.
>>
>> Fixed as part of the directive to remove all VLAs from
>> the kernel: https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
>> ---
>>   drivers/power/supply/da9150-fg.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/power/supply/da9150-fg.c b/drivers/power/supply/da9150-fg.c
>> index 8b8ce97..96893be 100644
>> --- a/drivers/power/supply/da9150-fg.c
>> +++ b/drivers/power/supply/da9150-fg.c
>> @@ -92,7 +92,7 @@ struct da9150_fg {
>>   static u32 da9150_fg_read_attr(struct da9150_fg *fg, u8 code, u8 size)
>>
>>   {
>> -	u8 buf[size];
>> +	u8 buf[DA9150_QIF_BYTE_SIZE];
> 
> You can use DA9150_QIF_LONG_SIZE as that's the biggest size of an attribute
> which can be accessed. This will also save a little space.
> 

I got it. I'll send v2 shortly.

Thanks for the feedback, Adam.
--
Gustavo