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drm/rockchip: dw-dp: get the real hpd state

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In DPTX Controller, when hpd signal is low, the hpd state will
change to unplug immediately. if the low level signal is less
than 2ms, the hpd state will change to plug state and trigger a
hpd irq interrupt.

In some case, driver will detect hpd state to get the plug/unplug
info when a hpd irq is coming. A hpd irq may be regard as a unplug
state. To avoid this issue, it better to wait the hpd state change
to the nest state.

Change-Id: I68c5bdc72128a2bc3ea990cfcb54e2ade755abc7
Signed-off-by: Zhang Yubing <yubing.zhang@rock-chips.com>
This commit is contained in:
Zhang Yubing
2024-02-28 11:04:36 +08:00
committed by Tao Huang
parent 969569b827
commit 09bbffb298
1 changed files with 8 additions and 1 deletions
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9
drivers/gpu/drm/rockchip/dw-dp.c
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@@ -1112,11 +1112,18 @@ static bool dw_dp_bandwidth_ok(struct dw_dp *dp,
static bool dw_dp_detect(struct dw_dp *dp)
{
u32 value;
int ret;
if (dp->hpd_gpio)
return gpiod_get_value_cansleep(dp->hpd_gpio);
regmap_read(dp->regmap, DPTX_HPD_STATUS, &value);
ret = regmap_read_poll_timeout(dp->regmap, DPTX_HPD_STATUS, value,
FIELD_GET(HPD_STATE, value) != SOURCE_STATE_UNPLUG,
100, 3000);
if (ret) {
dev_err(dp->dev, "get hpd status timeout\n");
return false;
}
return FIELD_GET(HPD_STATE, value) == SOURCE_STATE_PLUG;
}