[U-Boot] [PATCH][NEXT] hwmon: do not init sensors on startup

[Wolfgang Denk]

Dear Heiko Schocher,

In message <1291903238-29071-1-git-send-email-hs at denx.de> you wrote:
>
> --- a/common/cmd_dtt.c
> +++ b/common/cmd_dtt.c
> @@ -28,6 +28,8 @@
>  #include <dtt.h>
>  #include <i2c.h>
>  
> +static unsigned long sensors_init_done = 0;

What if there are more then 32 sensors?

>  int do_dtt (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
>  {
>  	int i;
> @@ -42,8 +44,16 @@ int do_dtt (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
>  	 * Loop through sensors, read
>  	 * temperature, and output it.
>  	 */
> -	for (i = 0; i < sizeof (sensors); i++)
> -		printf ("DTT%d: %i C\n", i + 1, dtt_get_temp (sensors[i]));
> +	for (i = 0; i < sizeof (sensors); i++) {
> +		if ((sensors_init_done & (1 << i)) != (1 << i)) {
> +			if (dtt_init_one(sensors[i]) == 0)
> +				sensors_init_done |= (1 << i);
> +			else
> +				printf("DTT%d: Failed init!\n", i);
> +		}
> +		if ((sensors_init_done & (1 << i)) == (1 << i))
> +			printf ("DTT%d: %i C\n", i + 1, dtt_get_temp(sensors[i]));
> +	}

This is overly complicated, it seems.  Why not:

	for (i = 0; i < sizeof(sensors); i++) {
		if ((sensors_init_done & (1 << i)) == 0) {
			if (dtt_init_one(sensors[i]) != 0) {
				printf("DTT%d: init failed\n", i);
				continue;
			}
			sensors_init_done |= (1 << i);
		}

		printf("DTT%d: %i C\n", i + 1, dtt_get_temp(sensors[i]));
	}


Best regards,

Wolfgang Denk

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