From 5a5efbf4ef504a8136963a8ae10a3c0a1d59b479 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Wed, 19 Jun 2019 21:03:07 +0300
Subject: drm/i915/sdvo: Fix handling if zero hbuf size
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Git-commit: 5a5efbf4ef504a8136963a8ae10a3c0a1d59b479
Patch-mainline: v5.4-rc1
References: bsc#1152489
The spec says:
"A value of 0 indicates that this buffer does not exist"
So we should not convert a hbuf_size of 0 into 1.
Also pull the relevant code into a helper to avoid making the
same mistake multiple times.
And while at it fix the debug prints to not say "hbuf_len" twice.
v2: s/%i/%u/ in the debug (Imre)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190619180312.31817-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/gpu/drm/i915/display/intel_sdvo.c | 32 ++++++++++++++---------
1 file changed, 19 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c b/drivers/gpu/drm/i915/display/intel_sdvo.c
index 3fe8eaef6bd8..213843a93c4e 100644
--- a/drivers/gpu/drm/i915/display/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/display/intel_sdvo.c
@@ -951,6 +951,20 @@ static bool intel_sdvo_set_audio_state(struct intel_sdvo *intel_sdvo,
&audio_state, 1);
}
+static bool intel_sdvo_get_hbuf_size(struct intel_sdvo *intel_sdvo,
+ u8 *hbuf_size)
+{
+ if (!intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_HBUF_INFO,
+ hbuf_size, 1))
+ return false;
+
+ /* Buffer size is 0 based, hooray! However zero means zero. */
+ if (*hbuf_size)
+ (*hbuf_size)++;
+
+ return true;
+}
+
#if 0
static void intel_sdvo_dump_hdmi_buf(struct intel_sdvo *intel_sdvo)
{
@@ -994,14 +1008,10 @@ static bool intel_sdvo_write_infoframe(struct intel_sdvo *intel_sdvo,
set_buf_index, 2))
return false;
- if (!intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_HBUF_INFO,
- &hbuf_size, 1))
+ if (!intel_sdvo_get_hbuf_size(intel_sdvo, &hbuf_size))
return false;
- /* Buffer size is 0 based, hooray! */
- hbuf_size++;
-
- DRM_DEBUG_KMS("writing sdvo hbuf: %i, hbuf_size %i, hbuf_size: %i\n",
+ DRM_DEBUG_KMS("writing sdvo hbuf: %i, length %u, hbuf_size: %i\n",
if_index, length, hbuf_size);
if (hbuf_size < length)
@@ -1052,14 +1062,10 @@ static ssize_t intel_sdvo_read_infoframe(struct intel_sdvo *intel_sdvo,
if (tx_rate == SDVO_HBUF_TX_DISABLED)
return 0;
- if (!intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_HBUF_INFO,
- &hbuf_size, 1))
- return -ENXIO;
-
- /* Buffer size is 0 based, hooray! */
- hbuf_size++;
+ if (!intel_sdvo_get_hbuf_size(intel_sdvo, &hbuf_size))
+ return false;
- DRM_DEBUG_KMS("reading sdvo hbuf: %i, hbuf_size %i, hbuf_size: %i\n",
+ DRM_DEBUG_KMS("reading sdvo hbuf: %i, length %u, hbuf_size: %i\n",
if_index, length, hbuf_size);
hbuf_size = min_t(unsigned int, length, hbuf_size);
--
2.28.0