[U-Boot] [PATCH] i2c, core: optimze i2c_set_bus_num()

[Lukasz Majewski <l.majewski@samsung.com>]

Hi Heiko,

> check first, if we are on the bus, we want to enable. If so,
> return immediately, do not calc max adapter number, nor check
> other things.
> 
> Signed-off-by: Heiko Schocher <hs@denx.de>
> Cc: Lukasz Majewski <l.majewski@samsung.com>
> ---
>  drivers/i2c/i2c_core.c | 18 ++++++++++--------
>  1 file changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/i2c/i2c_core.c b/drivers/i2c/i2c_core.c
> index d1072e8..170423a 100644
> --- a/drivers/i2c/i2c_core.c
> +++ b/drivers/i2c/i2c_core.c
> @@ -278,20 +278,22 @@ unsigned int i2c_get_bus_num(void)
>   */
>  int i2c_set_bus_num(unsigned int bus)
>  {
> -	int max = ll_entry_count(struct i2c_adapter, i2c);
> +	int max;
> +
> +	if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
> +		return 0;
>  
> -	if (I2C_ADAPTER(bus) >= max) {
> -		printf("Error, wrong i2c adapter %d max %d
> possible\n",
> -		       I2C_ADAPTER(bus), max);
> -		return -2;
> -	}
>  #ifndef CONFIG_SYS_I2C_DIRECT_BUS
>  	if (bus >= CONFIG_SYS_NUM_I2C_BUSES)
>  		return -1;
>  #endif
>  
> -	if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
> -		return 0;
> +	max = ll_entry_count(struct i2c_adapter, i2c);
> +	if (I2C_ADAPTER(bus) >= max) {
> +		printf("Error, wrong i2c adapter %d max %d
> possible\n",

Since you are the maintainer of the i2c code, you will decide if
those changes shall be applied (they are really cosmetic) :-).

My suggestion: printf -> error() macro @ common.h

> +		       I2C_ADAPTER(bus), max);
> +		return -2;

I've noticed that i2c_core uses -1/-2 return values for errors
globaly.

So for a new code we could start using defines from errno.h (-2 ->
-ENODEV) ?


> +	}
>  
>  #ifndef CONFIG_SYS_I2C_DIRECT_BUS
>  	i2c_mux_disconnet_all();



-- 
Best regards,

Lukasz Majewski

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