From c7581a414d28413c1dd6d116d44859b5a52e0950 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Wed, 4 Sep 2019 16:39:42 +0200 Subject: [PATCH] drm: Use EOPNOTSUPP, not ENOTSUPP MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit - it's what we recommend in our docs: https://dri.freedesktop.org/docs/drm/gpu/drm-uapi.html#recommended-ioctl-return-values - it's the overwhelmingly used error code for "operation not supported", at least in drm core (slightly less so in drivers): $ git grep EOPNOTSUPP -- drivers/gpu/drm/*c | wc -l 83 $ git grep ENOTSUPP -- drivers/gpu/drm/*c | wc -l 5 - include/linux/errno.h makes it fairly clear that these are for nfsv3 (plus they also have error codes above 512, which is the block with some special behaviour ...) /* Defined for the NFSv3 protocol */ If the above isn't reflecting current practice, then I guess we should at least update the docs. Noralf commented: Ben Hutchings made this comment[1] in a thread about use of ENOTSUPP in drivers: glibc's strerror() returns these strings for ENOTSUPP and EOPNOTSUPP respectively: "Unknown error 524" "Operation not supported" So at least for errors returned to userspace EOPNOTSUPP makes sense. José asked: > Hopefully this will not break any userspace None of the functions in drm_edid.c affected by this reach userspace, it's all driver internal. Same for the mipi function, that error code should be handled by drivers. Drivers are supposed to remap "the hw is on fire" to EIO when reporting up to userspace, but I think if a driver sees this it would be a driver bug. v2: Augment commit message with comments from Noralf and José Reviewed-by: José Roberto de Souza Acked-by: Noralf Trønnes Cc: José Roberto de Souza Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Sean Paul Cc: Alex Deucher Cc: Andres Rodriguez Cc: Noralf Trønnes Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20190904143942.31756-1-daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_edid.c | 6 +++--- drivers/gpu/drm/drm_mipi_dbi.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 82a4cee..12c783f 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3719,7 +3719,7 @@ cea_db_offsets(const u8 *cea, int *start, int *end) if (*end < 4 || *end > 127) return -ERANGE; } else { - return -ENOTSUPP; + return -EOPNOTSUPP; } return 0; @@ -4188,7 +4188,7 @@ int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads) if (cea_revision(cea) < 3) { DRM_DEBUG_KMS("SAD: wrong CEA revision\n"); - return -ENOTSUPP; + return -EOPNOTSUPP; } if (cea_db_offsets(cea, &start, &end)) { @@ -4249,7 +4249,7 @@ int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb) if (cea_revision(cea) < 3) { DRM_DEBUG_KMS("SAD: wrong CEA revision\n"); - return -ENOTSUPP; + return -EOPNOTSUPP; } if (cea_db_offsets(cea, &start, &end)) { diff --git a/drivers/gpu/drm/drm_mipi_dbi.c b/drivers/gpu/drm/drm_mipi_dbi.c index c4ee270..f815431 100644 --- a/drivers/gpu/drm/drm_mipi_dbi.c +++ b/drivers/gpu/drm/drm_mipi_dbi.c @@ -955,7 +955,7 @@ static int mipi_dbi_typec1_command(struct mipi_dbi *dbi, u8 *cmd, int ret; if (mipi_dbi_command_is_read(dbi, *cmd)) - return -ENOTSUPP; + return -EOPNOTSUPP; MIPI_DBI_DEBUG_COMMAND(*cmd, parameters, num); -- 2.7.4