[PATCH] arm/komeda: Convert dp_wait_cond() to return an error code.

[james qian wang (Arm Technology China)]

On Wed, Jun 05, 2019 at 12:19:29PM +0100, Liviu Dudau wrote:
> dp_wait_cond() currently returns the number of retries left over which
> is hardly an useful information. Convert to returning -ETIMEDOUT when
> the wait times out, or 0 (zero) when condition is met before deadline.
> 
> Also convert the users of the function to return the error value.
> 
> Signed-off-by: Liviu Dudau <liviu.dudau at arm.com>
> ---
>  drivers/gpu/drm/arm/display/include/malidp_utils.h | 5 ++---
>  drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c   | 4 ++--
>  2 files changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/arm/display/include/malidp_utils.h b/drivers/gpu/drm/arm/display/include/malidp_utils.h
> index 8cfd91196e15..3bc383d5bf73 100644
> --- a/drivers/gpu/drm/arm/display/include/malidp_utils.h
> +++ b/drivers/gpu/drm/arm/display/include/malidp_utils.h
> @@ -8,6 +8,7 @@
>  #define _MALIDP_UTILS_
>  
>  #include <linux/delay.h>
> +#include <linux/errno.h>
>  
>  #define has_bit(nr, mask)	(BIT(nr) & (mask))
>  #define has_bits(bits, mask)	(((bits) & (mask)) == (bits))
> @@ -20,11 +21,9 @@
>  	int num_tries = __tries;			\
>  	while (!__cond && (num_tries > 0)) {		\
>  		usleep_range(__min_range, __max_range);	\
> -		if (__cond)				\
> -			break;				\
>  		num_tries--;				\
>  	}						\
> -	num_tries;					\
> +	(__cond) ? 0 : -ETIMEDOUT;			\
>  })
>  
>  /* the restriction of range is [start, end] */
> diff --git a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> index 1c914f8ca016..68f27c5cffcd 100644
> --- a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> +++ b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> @@ -280,7 +280,7 @@ static int d71_change_opmode(struct komeda_dev *mdev, int new_mode)
>  	ret = dp_wait_cond(((malidp_read32(d71->gcu_addr, BLK_CONTROL) & 0x7) == opmode),
>  			   100, 1000, 10000);
>  
> -	return ret > 0 ? 0 : -ETIMEDOUT;
> +	return ret;
>  }
>  
>  static void d71_flush(struct komeda_dev *mdev,
> @@ -304,7 +304,7 @@ static int d71_reset(struct d71_dev *d71)
>  	ret = dp_wait_cond(!(malidp_read32(gcu, BLK_CONTROL) & GCU_CONTROL_SRST),
>  			   100, 1000, 10000);
>  
> -	return ret > 0 ? 0 : -ETIMEDOUT;
> +	return ret;
>  }
>  
>  void d71_read_block_header(u32 __iomem *reg, struct block_header *blk)
> -- 
> 2.21.0

Look good to me.

Reviewed-by: James Qian Wang (Arm Technology China) <james.qian.wang at arm.com>