[Openchrome-devel] [RFC 16/21] DRM: Add VIA DRM driver

[James Simmons]

commit a2e0f8fc0ded9788815cdc68d3acded9f43116b4
Author: James Simmons <jsimmons at infradead.org>
Date:   Sat Jun 8 12:08:57 2013 -0400

    via: TMDS support
    
    Implement the encoder and connector for TMDS devices. This handles the case
    of DVI port devices not based on an HDMI encoder. This is basic support will
    will need to be expanded in the future to handle more corner cases on older
    hardware.
    
    Signed-Off-by: James Simmons <jsimmons at infradead.org>

diff --git a/drivers/gpu/drm/via/via_tmds.c b/drivers/gpu/drm/via/via_tmds.c
new file mode 100644
index 0000000..a906661
--- /dev/null
+++ b/drivers/gpu/drm/via/via_tmds.c
@@ -0,0 +1,187 @@
+/*
+ * Copyright © 2013 James Simmons
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ *	James Simmons <jsimmons at infradead.org>
+ */
+#include "via_drv.h"
+
+/*
+ * Routines for controlling stuff on the TMDS port
+ */
+static const struct drm_encoder_funcs via_tmds_enc_funcs = {
+	.destroy = via_encoder_cleanup,
+};
+
+/* Manage the power state of the DAC */
+static void
+via_tmds_dpms(struct drm_encoder *encoder, int mode)
+{
+	struct drm_via_private *dev_priv = encoder->dev->dev_private;
+
+	switch (mode) {
+	case DRM_MODE_DPMS_SUSPEND:
+	case DRM_MODE_DPMS_STANDBY:
+	case DRM_MODE_DPMS_OFF:
+		svga_wcrt_mask(VGABASE, 0xD2, BIT(4), BIT(4));
+		svga_wcrt_mask(VGABASE, 0x91, 0x00, BIT(0));
+
+		/* Internal TMDS only use DFP_L */
+		/* Turn on DVI panel path(Only for internal),
+		 * otherwise, the screen of DVI will be black. */
+		svga_wcrt_mask(VGABASE, 0x91, 0x00, BIT(7));
+		/* Power on TMDS */
+		svga_wcrt_mask(VGABASE, 0xD2, 0x00, BIT(3));
+		break;
+
+	case DRM_MODE_DPMS_ON:
+	default:
+		svga_wcrt_mask(VGABASE, 0x91, BIT(7), BIT(7));
+		/* Power off TMDS */
+		svga_wcrt_mask(VGABASE, 0xD2, BIT(3), BIT(3));
+		break;
+	}
+}
+
+/* Pass our mode to the connectors and the CRTC to give them a chance to
+ * adjust it according to limitations or connector properties, and also
+ * a chance to reject the mode entirely. Usefule for things like scaling.
+ */
+static bool
+via_tmds_mode_fixup(struct drm_encoder *encoder,
+		 const struct drm_display_mode *mode,
+		 struct drm_display_mode *adjusted_mode)
+{
+	drm_mode_set_crtcinfo(adjusted_mode, 0);
+	return true;
+}
+
+static const struct drm_encoder_helper_funcs via_tmds_enc_helper_funcs = {
+	.dpms = via_tmds_dpms,
+	.mode_fixup = via_tmds_mode_fixup,
+	.mode_set = via_set_sync_polarity,
+	.prepare = via_encoder_prepare,
+	.commit = via_encoder_commit,
+	.disable = via_encoder_disable,
+};
+
+static enum drm_connector_status
+via_dvi_detect(struct drm_connector *connector, bool force)
+{
+	struct via_connector *con = container_of(connector, struct via_connector, base);
+	enum drm_connector_status ret = connector_status_disconnected;
+	struct edid *edid = NULL;
+
+	drm_mode_connector_update_edid_property(connector, edid);
+	if (con->ddc_bus) {
+		edid = drm_get_edid(connector, con->ddc_bus);
+		if (edid) {
+			if ((connector->connector_type == DRM_MODE_CONNECTOR_DVIA) ^
+			    (edid->input & DRM_EDID_INPUT_DIGITAL)) {
+				drm_mode_connector_update_edid_property(connector, edid);
+				ret = connector_status_connected;
+			}
+			kfree(edid);
+		}
+	}
+	return ret;
+}
+
+static const struct drm_connector_funcs via_dvi_connector_funcs = {
+	.dpms = drm_helper_connector_dpms,
+	.detect = via_dvi_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.set_property = via_connector_set_property,
+	.destroy = via_connector_destroy,
+};
+
+static const struct drm_connector_helper_funcs via_dvi_connector_helper_funcs = {
+	.mode_valid = via_connector_mode_valid,
+	.get_modes = via_get_edid_modes,
+	.best_encoder = via_best_encoder,
+};
+
+int
+via_tmds_init(struct drm_device *dev)
+{
+	struct drm_via_private *dev_priv = dev->dev_private;
+	struct via_connector *con;
+	struct via_encoder *enc;
+	int i2c_port = 0x3D;
+
+	if (!(vga_rseq(VGABASE, 0x3E) & BIT(5))) {
+		DRM_INFO("Internal DVI not detected\n");
+		return 1;
+	}
+
+	enc = kzalloc(sizeof(*enc) + 2 * sizeof(*con), GFP_KERNEL);
+	if (!enc) {
+		DRM_ERROR("Failed to allocate connector and encoder\n");
+		return -ENOMEM;
+	}
+
+	/* Setup the encoders and attach them */
+	drm_encoder_init(dev, &enc->base, &via_tmds_enc_funcs, DRM_MODE_ENCODER_DAC);
+	drm_encoder_helper_add(&enc->base, &via_tmds_enc_helper_funcs);
+
+	enc->base.possible_crtcs = BIT(1) | BIT(0);
+	enc->base.possible_clones = 0;
+	enc->diPort = DISP_DI_DFPL;
+
+	/* Piece together our DVI-D connector */
+	con = &enc->cons[0];
+	drm_connector_init(dev, &con->base, &via_dvi_connector_funcs,
+				DRM_MODE_CONNECTOR_DVID);
+	drm_connector_helper_add(&con->base, &via_dvi_connector_helper_funcs);
+	drm_sysfs_connector_add(&con->base);
+
+	switch (dev->pci_device) {
+	case PCI_DEVICE_ID_VIA_VT1122:
+		if (dev_priv->revision < VX800_REVISION_B1)
+			break;
+
+	case PCI_DEVICE_ID_VIA_VX875:
+	case PCI_DEVICE_ID_VIA_VX900:
+		i2c_port = 0x31;
+		break;
+	default:
+		break;
+	}
+	con->ddc_bus = via_find_ddc_bus(i2c_port);
+	con->base.doublescan_allowed = false;
+	con->base.interlace_allowed = true;
+
+	drm_mode_connector_attach_encoder(&con->base, &enc->base);
+
+	/* Now handle the DVI-A case */
+	con = &enc->cons[1];
+	drm_connector_init(dev, &con->base, &via_dvi_connector_funcs,
+				DRM_MODE_CONNECTOR_DVIA);
+	drm_connector_helper_add(&con->base, &via_dvi_connector_helper_funcs);
+	drm_sysfs_connector_add(&con->base);
+	con->ddc_bus = via_find_ddc_bus(i2c_port);
+	con->base.doublescan_allowed = false;
+	con->base.interlace_allowed = true;
+
+	drm_mode_connector_attach_encoder(&con->base, &enc->base);
+	return 0;
+}