[PATCH v15 06/11] drm/mediatek: Add MT8195 External DisplayPort support

From: Bo-Chen Chen
Date: Wed Jul 27 2022 - 00:51:09 EST

From: Guillaume Ranquet <granquet@xxxxxxxxxxxx>

This patch adds External DisplayPort support to the mt8195 eDP driver.

Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
Signed-off-by: Bo-Chen Chen <rex-bc.chen@xxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_dp.c | 181 +++++++++++++++++++++-----
drivers/gpu/drm/mediatek/mtk_dp_reg.h | 1 +
2 files changed, 146 insertions(+), 36 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 06eeecedd49e..ce817cb59445 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -103,6 +103,11 @@ static struct regmap_config mtk_dp_regmap_config = {
.name = "mtk-dp-registers",
};

+static bool mtk_dp_is_edp(struct mtk_dp *mtk_dp)
+{
+ return mtk_dp->next_bridge;
+}
+
static struct mtk_dp *mtk_dp_from_bridge(struct drm_bridge *b)
{
return container_of(b, struct mtk_dp, bridge);
@@ -341,6 +346,19 @@ static void mtk_dp_pg_enable(struct mtk_dp *mtk_dp, bool enable)
4 << PGEN_PATTERN_SEL_SHIFT, PGEN_PATTERN_SEL_MASK);
}

+static bool mtk_dp_plug_state(struct mtk_dp *mtk_dp)
+{
+ return mtk_dp->train_info.cable_plugged_in;
+}
+
+static bool mtk_dp_plug_state_avoid_pulse(struct mtk_dp *mtk_dp)
+{
+ bool ret;
+
+ return !(readx_poll_timeout(mtk_dp_plug_state, mtk_dp, ret, ret,
+ 4000, 7 * 4000));
+}
+
static void mtk_dp_aux_irq_clear(struct mtk_dp *mtk_dp)
{
mtk_dp_write(mtk_dp, MTK_DP_AUX_P0_3640,
@@ -778,35 +796,67 @@ static void mtk_dp_get_calibration_data(struct mtk_dp *mtk_dp)
return;
}

- cal_data->glb_bias_trim =
- check_cal_data_valid(mtk_dp, 1, 0x1e,
- (buf[3] >> 27) & 0x1f, 0xf);
- cal_data->clktx_impse =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[0] >> 9) & 0xf, 0x8);
- cal_data->ln_tx_impsel_pmos[0] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 28) & 0xf, 0x8);
- cal_data->ln_tx_impsel_nmos[0] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 24) & 0xf, 0x8);
- cal_data->ln_tx_impsel_pmos[1] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 20) & 0xf, 0x8);
- cal_data->ln_tx_impsel_nmos[1] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 16) & 0xf, 0x8);
- cal_data->ln_tx_impsel_pmos[2] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 12) & 0xf, 0x8);
- cal_data->ln_tx_impsel_nmos[2] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 8) & 0xf, 0x8);
- cal_data->ln_tx_impsel_pmos[3] =
- check_cal_data_valid(mtk_dp, 1, 0xe,
- (buf[2] >> 4) & 0xf, 0x8);
- cal_data->ln_tx_impsel_nmos[3] =
- check_cal_data_valid(mtk_dp, 1, 0xe, buf[2] & 0xf, 0x8);
+ if (mtk_dp_is_edp(mtk_dp)) {
+ cal_data->glb_bias_trim =
+ check_cal_data_valid(mtk_dp, 1, 0x1e,
+ (buf[3] >> 27) & 0x1f, 0xf);
+ cal_data->clktx_impse =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[0] >> 9) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[0] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 28) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[0] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 24) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[1] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 20) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[1] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 16) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[2] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 12) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[2] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 8) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[3] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[2] >> 4) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[3] =
+ check_cal_data_valid(mtk_dp, 1, 0xe, buf[2] & 0xf, 0x8);
+ } else {
+ cal_data->glb_bias_trim =
+ check_cal_data_valid(mtk_dp, 1, 0x1e,
+ (buf[0] >> 27) & 0x1f, 0xf);
+ cal_data->clktx_impse =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[0] >> 13) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[0] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 28) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[0] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 24) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[1] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 20) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[1] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 16) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[2] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 12) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[2] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 8) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_pmos[3] =
+ check_cal_data_valid(mtk_dp, 1, 0xe,
+ (buf[1] >> 4) & 0xf, 0x8);
+ cal_data->ln_tx_impsel_nmos[3] =
+ check_cal_data_valid(mtk_dp, 1, 0xe, buf[1] & 0xf, 0x8);
+ }

kfree(buf);
}
@@ -926,7 +976,10 @@ static void mtk_dp_video_mute(struct mtk_dp *mtk_dp, bool enable)
VIDEO_MUTE_SEL_DP_ENC0_P0_MASK |
VIDEO_MUTE_SW_DP_ENC0_P0_MASK);

- mtk_dp_sip_atf_call(mtk_dp, MTK_DP_SIP_ATF_EDP_VIDEO_UNMUTE, enable);
+ mtk_dp_sip_atf_call(mtk_dp,
+ mtk_dp_is_edp(mtk_dp) ?
+ MTK_DP_SIP_ATF_EDP_VIDEO_UNMUTE :
+ MTK_DP_SIP_ATF_VIDEO_UNMUTE, enable);
}

static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
@@ -1226,6 +1279,9 @@ static int mtk_dp_parse_capabilities(struct mtk_dp *mtk_dp)
drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
usleep_range(2000, 5000);

+ if (!mtk_dp_plug_state(mtk_dp))
+ return -ENODEV;
+
drm_dp_read_dpcd_caps(&mtk_dp->aux, mtk_dp->rx_cap);

train_info->link_rate = min_t(int, mtk_dp->max_linkrate,
@@ -1277,6 +1333,9 @@ static int mtk_dp_train_start(struct mtk_dp *mtk_dp)
u8 train_limit;
u8 max_link_rate;

+ if (!mtk_dp_plug_state_avoid_pulse(mtk_dp))
+ return -ENODEV;
+
link_rate = mtk_dp->rx_cap[1];
lane_count = mtk_dp->rx_cap[2] & 0x1F;

@@ -1412,6 +1471,9 @@ static irqreturn_t mtk_dp_hpd_event_thread(int hpd, void *dev)
{
struct mtk_dp *mtk_dp = dev;

+ dev_dbg(mtk_dp->dev, "drm_helper_hpd_irq_event\n");
+ drm_helper_hpd_irq_event(mtk_dp->bridge.dev);
+
if (mtk_dp->train_info.hpd_inerrupt) {
dev_dbg(mtk_dp->dev, "MTK_DP_HPD_INTERRUPT\n");
mtk_dp->train_info.hpd_inerrupt = false;
@@ -1452,9 +1514,20 @@ static irqreturn_t mtk_dp_hpd_event(int hpd, void *dev)
else
train_info->cable_plugged_in = false;

- mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
- DP_PWR_STATE_BANDGAP_TPLL_LANE,
- DP_PWR_STATE_MASK);
+ if (!train_info->cable_plugged_in) {
+ mtk_dp_video_mute(mtk_dp, true);
+
+ mtk_dp_initialize_priv_data(mtk_dp);
+ mtk_dp_set_idle_pattern(mtk_dp, true);
+
+ mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
+ DP_PWR_STATE_BANDGAP_TPLL,
+ DP_PWR_STATE_MASK);
+ } else {
+ mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
+ DP_PWR_STATE_BANDGAP_TPLL_LANE,
+ DP_PWR_STATE_MASK);
+ }
}

return IRQ_HANDLED;
@@ -1499,6 +1572,24 @@ static int mtk_dp_dt_parse(struct mtk_dp *mtk_dp,
return 0;
}

+static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
+{
+ struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge);
+ enum drm_connector_status ret = connector_status_disconnected;
+ u8 sink_count = 0;
+
+ if (mtk_dp_is_edp(mtk_dp))
+ return connector_status_connected;
+
+ if (mtk_dp_plug_state_avoid_pulse(mtk_dp)) {
+ drm_dp_dpcd_readb(&mtk_dp->aux, DP_SINK_COUNT, &sink_count);
+ if (DP_GET_SINK_COUNT(sink_count))
+ ret = connector_status_connected;
+ }
+
+ return ret;
+}
+
static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
struct drm_connector *connector)
{
@@ -1512,7 +1603,8 @@ static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
usleep_range(2000, 5000);

- new_edid = drm_get_edid(connector, &mtk_dp->aux.ddc);
+ if (mtk_dp_plug_state(mtk_dp))
+ new_edid = drm_get_edid(connector, &mtk_dp->aux.ddc);

if (!enabled)
drm_bridge_chain_post_disable(bridge);
@@ -1852,6 +1944,7 @@ static const struct drm_bridge_funcs mtk_dp_bridge_funcs = {
.atomic_disable = mtk_dp_bridge_atomic_disable,
.mode_valid = mtk_dp_bridge_mode_valid,
.get_edid = mtk_dp_get_edid,
+ .detect = mtk_dp_bdg_detect,
};

static int mtk_dp_probe(struct platform_device *pdev)
@@ -1873,9 +1966,15 @@ static int mtk_dp_probe(struct platform_device *pdev)
"failed to request dp irq resource\n");

mtk_dp->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
- if (IS_ERR(mtk_dp->next_bridge))
+ if (IS_ERR(mtk_dp->next_bridge) &&
+ PTR_ERR(mtk_dp->next_bridge) == -ENODEV) {
+ dev_info(dev,
+ "No panel connected in devicetree, continue as external DP\n");
+ mtk_dp->next_bridge = NULL;
+ } else if (IS_ERR(mtk_dp->next_bridge)) {
return dev_err_probe(dev, PTR_ERR(mtk_dp->next_bridge),
"Failed to get bridge\n");
+ }

ret = mtk_dp_dt_parse(mtk_dp, pdev);
if (ret)
@@ -1918,7 +2017,10 @@ static int mtk_dp_probe(struct platform_device *pdev)

mtk_dp->bridge.ops =
DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HPD;
- mtk_dp->bridge.type = DRM_MODE_CONNECTOR_eDP;
+ if (mtk_dp_is_edp(mtk_dp))
+ mtk_dp->bridge.type = DRM_MODE_CONNECTOR_eDP;
+ else
+ mtk_dp->bridge.type = DRM_MODE_CONNECTOR_DisplayPort;

drm_bridge_add(&mtk_dp->bridge);

@@ -1945,6 +2047,12 @@ static int mtk_dp_suspend(struct device *dev)
{
struct mtk_dp *mtk_dp = dev_get_drvdata(dev);

+ if (mtk_dp_plug_state(mtk_dp)) {
+ drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
+ /* Ensure the sink is off before shutting down power */
+ usleep_range(2000, 3000);
+ }
+
mtk_dp_power_disable(mtk_dp);

mtk_dp_hwirq_enable(mtk_dp, false);
@@ -1978,6 +2086,7 @@ static SIMPLE_DEV_PM_OPS(mtk_dp_pm_ops, mtk_dp_suspend, mtk_dp_resume);

static const struct of_device_id mtk_dp_of_match[] = {
{ .compatible = "mediatek,mt8195-edp-tx" },
+ { .compatible = "mediatek,mt8195-dp-tx" },
{},
};
MODULE_DEVICE_TABLE(of, mtk_dp_of_match);
diff --git a/drivers/gpu/drm/mediatek/mtk_dp_reg.h b/drivers/gpu/drm/mediatek/mtk_dp_reg.h
index 4ff8e9880dc9..59086eb82868 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp_reg.h
+++ b/drivers/gpu/drm/mediatek/mtk_dp_reg.h
@@ -14,6 +14,7 @@
#define SEC_OFFSET 0x4000

#define MTK_DP_SIP_ATF_EDP_VIDEO_UNMUTE (BIT(0) | BIT(5))
+#define MTK_DP_SIP_ATF_VIDEO_UNMUTE BIT(5)

#define DP_PHY_GLB_BIAS_GEN_00 0
#define RG_XTP_GLB_BIAS_INTR_CTRL GENMASK(20, 16)
--
2.18.0