[PATCH v16 4/8] drm/mediatek: Add MT8195 External DisplayPort support

From: Bo-Chen Chen
Date: Fri Aug 05 2022 - 06:17:40 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>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_dp.c | 190 +++++++++++++++++++++-----
drivers/gpu/drm/mediatek/mtk_dp_reg.h | 4 +
2 files changed, 158 insertions(+), 36 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 59fee814075b..00971ea2fadf 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -77,6 +77,7 @@ struct mtk_dp {
struct dp_cal_data cal_data;
u8 max_lanes;
u8 max_linkrate;
+ const struct mtk_dp_data *data;

struct drm_device *drm_dev;
struct drm_bridge bridge;
@@ -96,6 +97,12 @@ struct mtk_dp {
struct drm_connector *conn;
};

+struct mtk_dp_data {
+ int bridge_type;
+ unsigned int smp_cmd;
+ unsigned int cali_data_fmt;
+};
+
static struct regmap_config mtk_dp_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
@@ -347,6 +354,14 @@ 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,
@@ -784,35 +799,73 @@ 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);
+ /*
+ * To save the efuse bits, we place the calibration data for DP and eDP
+ * using method which could save the efuse bits. For this, the efuse
+ * orders of DP and eDP are different.
+ */
+
+ if (mtk_dp->data->cali_data_fmt == MTK_DP_CALI_DATA_FMT_MT8195_EDP) {
+ 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);
}
@@ -932,7 +985,7 @@ 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->data->smp_cmd, enable);
}

static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
@@ -1232,6 +1285,9 @@ 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,
@@ -1283,6 +1339,9 @@ 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;

@@ -1457,9 +1516,20 @@ 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;
}
@@ -1503,6 +1573,21 @@ 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_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)
{
@@ -1857,6 +1942,7 @@ 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)
@@ -1871,6 +1957,7 @@ static int mtk_dp_probe(struct platform_device *pdev)
return -ENOMEM;

mtk_dp->dev = dev;
+ mtk_dp->data = (struct mtk_dp_data *)of_device_get_match_data(dev);

irq_num = platform_get_irq(pdev, 0);
if (irq_num < 0)
@@ -1878,9 +1965,15 @@ 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)
@@ -1923,7 +2016,7 @@ 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;
+ mtk_dp->bridge.type = mtk_dp->data->bridge_type;

drm_bridge_add(&mtk_dp->bridge);

@@ -1950,6 +2043,12 @@ 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);
@@ -1981,8 +2080,27 @@ static int mtk_dp_resume(struct device *dev)

static SIMPLE_DEV_PM_OPS(mtk_dp_pm_ops, mtk_dp_suspend, mtk_dp_resume);

+static const struct mtk_dp_data mt8195_edp_data = {
+ .bridge_type = DRM_MODE_CONNECTOR_eDP,
+ .smp_cmd = MTK_DP_SIP_ATF_EDP_VIDEO_UNMUTE,
+ .cali_data_fmt = MTK_DP_CALI_DATA_FMT_MT8195_EDP,
+};
+
+static const struct mtk_dp_data mt8195_dp_data = {
+ .bridge_type = DRM_MODE_CONNECTOR_DisplayPort,
+ .smp_cmd = MTK_DP_SIP_ATF_VIDEO_UNMUTE,
+ .cali_data_fmt = MTK_DP_CALI_DATA_FMT_MT8195_DP,
+};
+
static const struct of_device_id mtk_dp_of_match[] = {
- { .compatible = "mediatek,mt8195-edp-tx" },
+ {
+ .compatible = "mediatek,mt8195-edp-tx",
+ .data = &mt8195_edp_data,
+ },
+ {
+ .compatible = "mediatek,mt8195-dp-tx",
+ .data = &mt8195_dp_data,
+ },
{},
};
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 3676d71bd816..c12742adaa3c 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp_reg.h
+++ b/drivers/gpu/drm/mediatek/mtk_dp_reg.h
@@ -14,6 +14,10 @@
#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 MTK_DP_CALI_DATA_FMT_MT8195_EDP 0
+#define MTK_DP_CALI_DATA_FMT_MT8195_DP 1

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