[igt-dev] [PATCH i-g-t 4/4] tests/kms_dp_aux_dev: Add drm_dp_aux test

[Chris Wilson]

Quoting Ville Syrjala (2019-12-03 15:35:55)
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Add a basic test for /dev/drm_dp_aux. We just try to read 16 bytes
> from each connector's aux device, and if succesful we do a few
> quick sanity checks on the data.
> 
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  tests/Makefile.sources |   1 +
>  tests/kms_dp_aux_dev.c | 117 +++++++++++++++++++++++++++++++++++++++++
>  tests/meson.build      |   1 +
>  3 files changed, 119 insertions(+)
>  create mode 100644 tests/kms_dp_aux_dev.c
> 
> diff --git a/tests/Makefile.sources b/tests/Makefile.sources
> index 17980ed607d1..1d37228655e4 100644
> --- a/tests/Makefile.sources
> +++ b/tests/Makefile.sources
> @@ -42,6 +42,7 @@ TESTS_progs = \
>         kms_cursor_crc \
>         kms_cursor_edge_walk \
>         kms_cursor_legacy \
> +       kms_dp_aux_dev \
>         kms_dp_dsc \
>         kms_dp_tiled_display \
>         kms_draw_crc \
> diff --git a/tests/kms_dp_aux_dev.c b/tests/kms_dp_aux_dev.c
> new file mode 100644
> index 000000000000..8db85899cf4d
> --- /dev/null
> +++ b/tests/kms_dp_aux_dev.c
> @@ -0,0 +1,117 @@
> +/*
> + * Copyright © 2019 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + *
> + */
> +
> +#include "config.h"
> +
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <dirent.h>
> +
> +#include "igt.h"
> +#include "igt_kms.h"
> +
> +IGT_TEST_DESCRIPTION("Test that /dev/drm_dp_aux reads work");
> +
> +static bool test(int drm_fd, uint32_t connector_id)
> +{
> +       drmModeConnector *connector;
> +       DIR *dir;
> +       int dir_fd;
> +
> +       connector = drmModeGetConnectorCurrent(drm_fd, connector_id);
> +       dir_fd = igt_connector_sysfs_open(drm_fd, connector);
> +       drmModeFreeConnector(connector);
> +       igt_assert(dir_fd >= 0);
> +
> +       dir = fdopendir(dir_fd);
> +       igt_assert(dir);
> +
> +       for (;;) {
> +               struct dirent *ent;
> +               char path[5 + sizeof(ent->d_name)];
> +               uint8_t buf[16];
> +               int fd, ret;
> +
> +               ent = readdir(dir);
> +               if (!ent)
> +                       break;
> +
> +               if (strncmp(ent->d_name, "drm_dp_aux", 10))
> +                       continue;

So find the drm_dp_aux name for this connector and open it in /dev/

> +               snprintf(path, sizeof(path), "/dev/%s", ent->d_name);
> +
> +               fd = open(path, O_RDONLY);
> +               igt_assert(fd >= 0);
> +
> +               ret = read(fd, buf, sizeof(buf));
> +               igt_assert(ret == sizeof(buf) || errno == ETIMEDOUT);
> +
> +               igt_info("%s: %s\n", path,
> +                        ret > 0 ? "success" : "timed out");

Expect to be able to read 16 bytes.

> +
> +               close(fd);
> +
> +               closedir(dir);
> +               close(dir_fd);
> +
> +               if (ret > 0) {
> +                       /* DPCD rev sanity check */
> +                       igt_assert(buf[0] == 0x10 ||
> +                                  buf[0] == 0x11 ||
> +                                  buf[0] == 0x12 ||
> +                                  buf[0] == 0x13 ||
> +                                  buf[0] == 0x14);
> +                       /* DPCD max lane count sanity check */
> +                       igt_assert((buf[2] & 0x1f) == 0x01 ||
> +                                  (buf[2] & 0x1f) == 0x02 ||
> +                                  (buf[2] & 0x1f) == 0x04);

I believe you.

Might be worth using igt_assert_f() as I doubt these will make much
sense if they ever fail.

> +               }
> +
> +               return ret > 0;

Only care about drm_dp_aux, and there should only be one.
> +       }
> +
> +       closedir(dir);
> +       close(dir_fd);
> +       return false;
> +}
> +
> +igt_simple_main
> +{
> +       int valid_connectors = 0;
> +       drmModeRes *res;
> +       int drm_fd;
> +
> +       drm_fd = drm_open_driver_master(DRIVER_ANY);
> +
> +       res = drmModeGetResources(drm_fd);
> +       igt_require(res);
> +
> +       for (int i = 0; i < res->count_connectors; i++)
> +               valid_connectors += test(drm_fd, res->connectors[i]);
> +       igt_require(valid_connectors);
> +
> +       drmModeFreeResources(res);

I was able to follow along, so
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris