From: Chris Morgan <[email protected]> Add support for the dw-hdmi-qp driver to handle devices with missing HPD pins.
Since in this situation we are now polling for the EDID data via i2c change the error message to a rate limited debug message when we are unable to complete an i2c read, as a disconnected device would otherwise fill dmesg with i2c read errors. Reviewed-by: Cristian Ciocaltea <[email protected]> Signed-off-by: Chris Morgan <[email protected]> --- drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c | 34 +++++++++++++++++--- 1 file changed, 30 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c index 39332c57f2c5..929b2e95a5c5 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c @@ -145,6 +145,7 @@ struct dw_hdmi_qp { struct regmap *regm; unsigned long tmds_char_rate; + bool no_hpd; }; static void dw_hdmi_qp_write(struct dw_hdmi_qp *hdmi, unsigned int val, @@ -535,14 +536,22 @@ static int dw_hdmi_qp_i2c_read(struct dw_hdmi_qp *hdmi, stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10); if (!stat) { - dev_err(hdmi->dev, "i2c read timed out\n"); + if (hdmi->no_hpd) + dev_dbg_ratelimited(hdmi->dev, + "i2c read timed out\n"); + else + dev_err(hdmi->dev, "i2c read timed out\n"); dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0); return -EAGAIN; } /* Check for error condition on the bus */ if (i2c->stat & I2CM_NACK_RCVD_IRQ) { - dev_err(hdmi->dev, "i2c read error\n"); + if (hdmi->no_hpd) + dev_dbg_ratelimited(hdmi->dev, + "i2c read error\n"); + else + dev_err(hdmi->dev, "i2c read error\n"); dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0); return -EIO; } @@ -879,6 +888,15 @@ static enum drm_connector_status dw_hdmi_qp_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector) { struct dw_hdmi_qp *hdmi = bridge->driver_private; + const struct drm_edid *drm_edid; + + if (hdmi->no_hpd) { + drm_edid = drm_edid_read_ddc(connector, bridge->ddc); + if (drm_edid) + return connector_status_connected; + else + return connector_status_disconnected; + } return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data); } @@ -904,6 +922,11 @@ dw_hdmi_qp_bridge_tmds_char_rate_valid(const struct drm_bridge *bridge, { struct dw_hdmi_qp *hdmi = bridge->driver_private; + /* + * TODO: when hdmi->no_hpd is 1 we must not support modes that + * require scrambling, including every mode with a clock above + * HDMI14_MAX_TMDSCLK. + */ if (rate > HDMI14_MAX_TMDSCLK) { dev_dbg(hdmi->dev, "Unsupported TMDS char rate: %lld\n", rate); return MODE_CLOCK_HIGH; @@ -1074,12 +1097,15 @@ struct dw_hdmi_qp *dw_hdmi_qp_bind(struct platform_device *pdev, if (ret) return ERR_PTR(ret); + hdmi->no_hpd = device_property_read_bool(dev, "no-hpd"); + hdmi->bridge.driver_private = hdmi; hdmi->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HDMI | - DRM_BRIDGE_OP_HDMI_AUDIO | - DRM_BRIDGE_OP_HPD; + DRM_BRIDGE_OP_HDMI_AUDIO; + if (!hdmi->no_hpd) + hdmi->bridge.ops |= DRM_BRIDGE_OP_HPD; hdmi->bridge.of_node = pdev->dev.of_node; hdmi->bridge.type = DRM_MODE_CONNECTOR_HDMIA; hdmi->bridge.vendor = "Synopsys"; -- 2.43.0
