From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eugeni Dodonov Subject: [PATCH 1/2] Give up on edid retries when i2c tells us that bus is not there Date: Mon, 17 Oct 2011 11:12:29 -0200 Message-ID: <1318857150-2117-2-git-send-email-eugeni.dodonov@intel.com> References: <1318857150-2117-1-git-send-email-eugeni.dodonov@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1318857150-2117-1-git-send-email-eugeni.dodonov@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org, Eugeni Dodonov List-Id: dri-devel@lists.freedesktop.org This allows to avoid talking to a non-existent bus repeatedly until we finally timeout. The non-existent bus is signalled by -ENXIO error, provided by i2c_algo_bit:bit_doAddress call. As the advantage of such change, all the other routines which use drm_get_edid would benefit for this timeout. This change should fix https://bugs.freedesktop.org/show_bug.cgi?id=41059 and improve overall edid detection timing by 10-30% in most cases, and by a much larger margin in case of phantom outputs. Signed-off-by: Eugeni Dodonov --- drivers/gpu/drm/drm_edid.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 7425e5c..1bca6d7 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -265,6 +265,11 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, unsigned char *buf, } }; ret = i2c_transfer(adapter, msgs, 2); + if (ret == -ENXIO) { + DRM_DEBUG_KMS("drm: skipping non-existent adapter %s\n", + adapter->name); + break; + } } while (ret != 2 && --retries); return ret == 2 ? 0 : -1; -- 1.7.7