diff options
| author | Andrzej Hajda <a.hajda@samsung.com> | 2018-01-15 18:33:57 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-08-24 13:08:56 +0200 |
| commit | 69004038f01ccbccc5c99dd8a287331b77acc1b9 (patch) | |
| tree | a92aae896ed532c43d1c4a730c7fb8b47d0fd721 | |
| parent | da327a4b9d096a0734fc345ea96b483feafd0b4b (diff) | |
| download | linux-69004038f01ccbccc5c99dd8a287331b77acc1b9.tar.gz | |
drm/bridge/sii8620: fix loops in EDID fetch logic
[ Upstream commit 8e627a1b1ce8feb3e1da4428b71b9b4905f04888 ]
Function should constantly check if cable is connected and finish
in finite time.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Maciej Purski <m.purski@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180115173357.31067-4-a.hajda@samsung.com
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/gpu/drm/bridge/sil-sii8620.c | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c index 5131bfb94f065c..8b17a806ee6fd9 100644 --- a/drivers/gpu/drm/bridge/sil-sii8620.c +++ b/drivers/gpu/drm/bridge/sil-sii8620.c @@ -788,6 +788,7 @@ static void sii8620_burst_rx_all(struct sii8620 *ctx) static void sii8620_fetch_edid(struct sii8620 *ctx) { u8 lm_ddc, ddc_cmd, int3, cbus; + unsigned long timeout; int fetched, i; int edid_len = EDID_LENGTH; u8 *edid; @@ -837,23 +838,31 @@ static void sii8620_fetch_edid(struct sii8620 *ctx) REG_DDC_CMD, ddc_cmd | VAL_DDC_CMD_ENH_DDC_READ_NO_ACK ); - do { - int3 = sii8620_readb(ctx, REG_INTR3); + int3 = 0; + timeout = jiffies + msecs_to_jiffies(200); + for (;;) { cbus = sii8620_readb(ctx, REG_CBUS_STATUS); - - if (int3 & BIT_DDC_CMD_DONE) - break; - - if (!(cbus & BIT_CBUS_STATUS_CBUS_CONNECTED)) { + if (~cbus & BIT_CBUS_STATUS_CBUS_CONNECTED) { + kfree(edid); + edid = NULL; + goto end; + } + if (int3 & BIT_DDC_CMD_DONE) { + if (sii8620_readb(ctx, REG_DDC_DOUT_CNT) + >= FETCH_SIZE) + break; + } else { + int3 = sii8620_readb(ctx, REG_INTR3); + } + if (time_is_before_jiffies(timeout)) { + ctx->error = -ETIMEDOUT; + dev_err(ctx->dev, "timeout during EDID read\n"); kfree(edid); edid = NULL; goto end; } - } while (1); - - sii8620_readb(ctx, REG_DDC_STATUS); - while (sii8620_readb(ctx, REG_DDC_DOUT_CNT) < FETCH_SIZE) usleep_range(10, 20); + } sii8620_read_buf(ctx, REG_DDC_DATA, edid + fetched, FETCH_SIZE); if (fetched + FETCH_SIZE == EDID_LENGTH) { |