[PATCH 4.4 24/31] drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: John Stultz <john.stultz@linaro.org>

commit 6d5104c5a6b56385426e15047050584794bb6254 upstream.

In chasing down a previous issue with EDID probing from calling
drm_helper_hpd_irq_event() from irq context, Laurent noticed
that the DRM documentation suggests that
drm_kms_helper_hotplug_event() should be used instead.

Thus this patch replaces drm_helper_hpd_irq_event() with
drm_kms_helper_hotplug_event(), which requires we update the
connector.status entry and only call _hotplug_event() when the
status changes.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1484614372-15342-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thong Ho <thong.ho.px@rvc.renesas.com>
Signed-off-by: Nhan Nguyen <nhan.nguyen.yb@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/i2c/adv7511.c |   15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/i2c/adv7511.c
+++ b/drivers/gpu/drm/i2c/adv7511.c
@@ -435,8 +435,21 @@ static bool adv7511_hpd(struct adv7511 *
 static void adv7511_hpd_work(struct work_struct *work)
 {
 	struct adv7511 *adv7511 = container_of(work, struct adv7511, hpd_work);
+	enum drm_connector_status status;
+	unsigned int val;
+	int ret;
+	ret = regmap_read(adv7511->regmap, ADV7511_REG_STATUS, &val);
+	if (ret < 0)
+		status = connector_status_disconnected;
+	else if (val & ADV7511_STATUS_HPD)
+		status = connector_status_connected;
+	else
+		status = connector_status_disconnected;
 
-	drm_helper_hpd_irq_event(adv7511->connector.dev);
+	if (adv7511->connector.status != status) {
+		adv7511->connector.status = status;
+		drm_kms_helper_hotplug_event(adv7511->connector.dev);
+	}
 }
 
 static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)