On 2020-03-23 08:32, Anshuman Gupta wrote:
> This lib function evaluate the lpsp capability from
> the connector specific debugfs attribute i915_lpsp_info.
> 
> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> ---
>  lib/igt_pm.c | 27 +++++++++++++++++++++++++++
>  lib/igt_pm.h |  1 +
>  2 files changed, 28 insertions(+)
> 
> diff --git a/lib/igt_pm.c b/lib/igt_pm.c
> index 9d441e1b..7a6cab7c 100644
> --- a/lib/igt_pm.c
> +++ b/lib/igt_pm.c
> @@ -37,6 +37,7 @@
>  #include <dirent.h>
>  
>  #include "drmtest.h"
> +#include "igt_kms.h"
>  #include "igt_pm.h"
>  #include "igt_aux.h"
>  #include "igt_sysfs.h"
> @@ -827,3 +828,29 @@ bool igt_pm_pc8_plus_residencies_enabled(int msr_fd)
>  
>  	return true;
>  }
> +
> +/**
> + * igt_output_is_lpsp_capable:
> + * @drm_fd: fd to drm device
> + * @output: igt output for which lpsp capability need to be evaluated
> + * Check lpsp capability for a given output.
> + *
> + * Returns:
> + * True if given output is lpsp capable otherwise false.
> + */
> +bool igt_output_is_lpsp_capable(int drm_fd, igt_output_t *output)

Do we have a file for i915-specific features? If not, maybe prefixing
the function with i915 would help readers understand that this is an
i915-specific function.

> +{
> +	char buf[256];
> +	int fd, len;
> +
> +	fd = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
> +	igt_require(fd >= 0);
> +	len = igt_debugfs_simple_read(fd, "i915_lpsp_info", buf, sizeof(buf));
> +
> +	if (len < 0)
> +		igt_assert_eq(len, -ENODEV);
> +
> +	close(fd);
> +
> +	return strstr(buf, "LPSP capable");
> +}
> diff --git a/lib/igt_pm.h b/lib/igt_pm.h
> index 5e438452..076d8c27 100644
> --- a/lib/igt_pm.h
> +++ b/lib/igt_pm.h
> @@ -53,5 +53,6 @@ enum igt_runtime_pm_status igt_get_runtime_pm_status(void);
>  bool igt_wait_for_pm_status(enum igt_runtime_pm_status status);
>  bool igt_pm_dmc_loaded(int debugfs);
>  bool igt_pm_pc8_plus_residencies_enabled(int msr_fd);
> +bool igt_output_is_lpsp_capable(int drm_fd, igt_output_t *output);
>  
>  #endif /* IGT_PM_H */
>