[igt-dev] [PATCH i-g-t 5/6] tools/dpcd_reg: Make --count optional.

[Dhinakaran Pandiyan]

On Fri, 2018-08-31 at 21:18 -0700, Rodrigo Vivi wrote:
> Defaults to 1 when not explicitly defined.
> 
> Cc: Tarun Vyas <tarun.vyas at intel.com>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
>  tools/dpcd_reg.c | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/dpcd_reg.c b/tools/dpcd_reg.c
> index c533401c..a141f1fc 100644
> --- a/tools/dpcd_reg.c
> +++ b/tools/dpcd_reg.c
> @@ -170,7 +170,7 @@ int main(int argc, char **argv)
>  	} cmd = DUMP;
>  
>  	struct option longopts [] = {
> -		{
> "count",      required_argument,      NULL,      'c' },
> +		{
> "count",      optional_argument,      NULL,      'c' },
Passing count can be optional, but when count is passed it should
require an argument.

>From what I understand, this change makes passing an argument to count
optional.

>  		{ "device",	required_argument,	NULL,  
>     'd' },
>  		{ "help", 	no_argument, 		&help
> _flg,  2  },
>  		{ "offset",	required_argument,	NULL,	
>    'o' },
> @@ -227,10 +227,15 @@ int main(int argc, char **argv)
>  	}
>  
>  	if (cmd != DUMP && offset == INVALID) {
> -		printf("Offset needed for this operation\n");
> +		igt_warn("Offset needed for this operation\n");
>  		print_usage(argv[0], 0);
>  	}
>  
> +	if (cmd != DUMP && count == INVALID) {
> +		igt_debug("count not defined, defaults to 1
> byte\n");
> +		count = 1;
> +	}
> +
>  	memset(dev_name, '\0', 20);
>  	snprintf(dev_name, sizeof(aux_dev) + 2, "%s%d", aux_dev,
> devid);
>  
> @@ -243,20 +248,12 @@ int main(int argc, char **argv)
>  
>  	switch (cmd) {
>  	case READ:
> -		if (count == INVALID) {
> -			igt_warn("Please specify the count in
> bytes\n");
> -			print_usage(argv[0], 0);
> -		}
>  		ret = dpcd_read(fd, offset, count);
>  		if (ret != count)
>  			igt_warn("Failed to read from %s aux
> device\n",
>  				 dev_name);
>  		break;
>  	case WRITE:
> -		if (val == INVALID) {
> -			igt_warn("Write value is missing\n");
> -			print_usage(argv[0], 0);
> -		}
>  		ret = dpcd_write(fd, offset, &val);
>  		if (ret < 0)
>  			igt_warn("Failed to write to %s aux
> device\n",