[PATCH v9 18/38] phy: rockchip: usbdp: Drop DP HPD handling

[Sebastian Reichel <sebastian.reichel@collabora.com>]

Drop the HPD handling logic from the USBDP PHY. The registers involved
require the display controller power domain being enabled and thus the
HPD signal should be handled by the displayport controller itself.
Apart from that the HPD handling as it is done here is incorrect and
misses hotplug events happening after the USB-C connector (e.g. when
a USB-C to HDMI adapter is involved and the HDMI cable is replugged).

Proper USB-C DP HPD support requires some restructuring of the DP
controller driver, which will happen independent of this patch. The
mainline kernel does not yet support USB-C DP AltMode on RK3588 and
RK3576, so it is fine to drop this code without adding the counterpart
in the DRM in an atomic change.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
---
 drivers/phy/rockchip/phy-rockchip-usbdp.c | 81 ++++---------------------------
 1 file changed, 9 insertions(+), 72 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-usbdp.c b/drivers/phy/rockchip/phy-rockchip-usbdp.c
index b3de16557c32..928466659486 100644
--- a/drivers/phy/rockchip/phy-rockchip-usbdp.c
+++ b/drivers/phy/rockchip/phy-rockchip-usbdp.c
@@ -186,14 +186,11 @@ struct rk_udphy {
 	u32 dp_lane_sel[4];
 	u32 dp_aux_dout_sel;
 	u32 dp_aux_din_sel;
-	bool dp_sink_hpd_sel;
-	bool dp_sink_hpd_cfg;
 	unsigned int link_rate;
 	unsigned int lanes;
 	u8 bw;
 	int id;
 
-	bool dp_in_use;
 	int dp_lanes;
 
 	/* PHY const config */
@@ -582,19 +579,6 @@ static void rk_udphy_dp_lane_enable(struct rk_udphy *udphy, int dp_lanes)
 				   CMN_DP_CMN_RSTN, FIELD_PREP(CMN_DP_CMN_RSTN, 0x0));
 }
 
-static void rk_udphy_dp_hpd_event_trigger(struct rk_udphy *udphy, bool hpd)
-{
-	const struct rk_udphy_cfg *cfg = udphy->cfgs;
-
-	udphy->dp_sink_hpd_sel = true;
-	udphy->dp_sink_hpd_cfg = hpd;
-
-	if (!udphy->dp_in_use)
-		return;
-
-	rk_udphy_grfreg_write(udphy->vogrf, &cfg->vogrfcfg[udphy->id].hpd_trigger, hpd);
-}
-
 static void rk_udphy_mode_set(struct rk_udphy *udphy, u8 mode)
 {
 	if (udphy->mode == mode)
@@ -1035,29 +1019,6 @@ static void rk_udphy_power_off(struct rk_udphy *udphy, u8 mode)
 		rk_udphy_disable(udphy);
 }
 
-static int rk_udphy_dp_phy_init(struct phy *phy)
-{
-	struct rk_udphy *udphy = phy_get_drvdata(phy);
-
-	mutex_lock(&udphy->mutex);
-
-	udphy->dp_in_use = true;
-
-	mutex_unlock(&udphy->mutex);
-
-	return 0;
-}
-
-static int rk_udphy_dp_phy_exit(struct phy *phy)
-{
-	struct rk_udphy *udphy = phy_get_drvdata(phy);
-
-	mutex_lock(&udphy->mutex);
-	udphy->dp_in_use = false;
-	mutex_unlock(&udphy->mutex);
-	return 0;
-}
-
 static int rk_udphy_dp_phy_power_on(struct phy *phy)
 {
 	struct rk_udphy *udphy = phy_get_drvdata(phy);
@@ -1289,8 +1250,6 @@ static int rk_udphy_dp_phy_configure(struct phy *phy,
 }
 
 static const struct phy_ops rk_udphy_dp_phy_ops = {
-	.init		= rk_udphy_dp_phy_init,
-	.exit		= rk_udphy_dp_phy_exit,
 	.power_on	= rk_udphy_dp_phy_power_on,
 	.power_off	= rk_udphy_dp_phy_power_off,
 	.configure	= rk_udphy_dp_phy_configure,
@@ -1344,6 +1303,14 @@ static int rk_udphy_typec_mux_set(struct typec_mux_dev *mux,
 	struct rk_udphy *udphy = typec_mux_get_drvdata(mux);
 	u8 mode;
 
+	/*
+	 * Ignore mux events not involving DP AltMode, because
+	 * the mode field is being reused, e.g. state->mode == 4
+	 * could be either TYPEC_MODE_USB4 or TYPEC_DP_STATE_C.
+	 */
+	if (!state->alt || state->alt->svid != USB_TYPEC_DP_SID)
+		return 0;
+
 	mutex_lock(&udphy->mutex);
 
 	switch (state->mode) {
@@ -1375,22 +1342,7 @@ static int rk_udphy_typec_mux_set(struct typec_mux_dev *mux,
 		break;
 	}
 
-	if (state->alt && state->alt->svid == USB_TYPEC_DP_SID) {
-		struct typec_displayport_data *data = state->data;
-
-		if (!data) {
-			rk_udphy_dp_hpd_event_trigger(udphy, false);
-		} else if (data->status & DP_STATUS_IRQ_HPD) {
-			rk_udphy_dp_hpd_event_trigger(udphy, false);
-			usleep_range(750, 800);
-			rk_udphy_dp_hpd_event_trigger(udphy, true);
-		} else if (data->status & DP_STATUS_HPD_STATE) {
-			rk_udphy_mode_set(udphy, mode);
-			rk_udphy_dp_hpd_event_trigger(udphy, true);
-		} else {
-			rk_udphy_dp_hpd_event_trigger(udphy, false);
-		}
-	}
+	rk_udphy_mode_set(udphy, mode);
 
 	mutex_unlock(&udphy->mutex);
 	return 0;
@@ -1549,20 +1501,6 @@ static int rk_udphy_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int __maybe_unused rk_udphy_resume(struct device *dev)
-{
-	struct rk_udphy *udphy = dev_get_drvdata(dev);
-
-	if (udphy->dp_sink_hpd_sel)
-		rk_udphy_dp_hpd_event_trigger(udphy, udphy->dp_sink_hpd_cfg);
-
-	return 0;
-}
-
-static const struct dev_pm_ops rk_udphy_pm_ops = {
-	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, rk_udphy_resume)
-};
-
 static const char * const rk_udphy_rst_list[] = {
 	"init", "cmn", "lane", "pcs_apb", "pma_apb"
 };
@@ -1667,7 +1605,6 @@ static struct platform_driver rk_udphy_driver = {
 	.driver		= {
 		.name	= "rockchip-usbdp-phy",
 		.of_match_table = rk_udphy_dt_match,
-		.pm = &rk_udphy_pm_ops,
 	},
 };
 module_platform_driver(rk_udphy_driver);

-- 
2.53.0