DRM: Armada: Add Armada DRM driver

This patch adds support for the pair of LCD controllers on the Marvell
Armada 510 SoCs.  This driver supports:
- multiple contiguous scanout buffers for video and graphics
- shm backed cacheable buffer objects for X pixmaps for Vivante GPU
  acceleration
- dual lcd0 and lcd1 crt operation
- video overlay on each LCD crt via DRM planes
- page flipping of the main scanout buffers
- DRM prime for buffer export/import

This driver is trivial to extend to other Armada SoCs.

Included in this commit is the core driver with no output support; output
support is platform and encoder driver dependent.

Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 139 insertions, 0 deletions

diff --git a/drivers/gpu/drm/armada/armada_slave.c b/drivers/gpu/drm/armada/armada_slave.c
new file mode 100644
index 00000000000..00d0facb42f
--- /dev/null
+++ b/drivers/gpu/drm/armada/armada_slave.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2012 Russell King
+ *  Rewritten from the dovefb driver, and Armada510 manuals.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <drm/drmP.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_encoder_slave.h>
+#include "armada_drm.h"
+#include "armada_output.h"
+#include "armada_slave.h"
+
+static int armada_drm_slave_get_modes(struct drm_connector *conn)
+{
+	struct drm_encoder *enc = armada_drm_connector_encoder(conn);
+	int count = 0;
+
+	if (enc) {
+		struct drm_encoder_slave *slave = to_encoder_slave(enc);
+
+		count = slave->slave_funcs->get_modes(enc, conn);
+	}
+
+	return count;
+}
+
+static void armada_drm_slave_destroy(struct drm_encoder *enc)
+{
+	struct drm_encoder_slave *slave = to_encoder_slave(enc);
+	struct i2c_client *client = drm_i2c_encoder_get_client(enc);
+
+	if (slave->slave_funcs)
+		slave->slave_funcs->destroy(enc);
+	if (client)
+		i2c_put_adapter(client->adapter);
+
+	drm_encoder_cleanup(&slave->base);
+	kfree(slave);
+}
+
+static const struct drm_encoder_funcs armada_drm_slave_encoder_funcs = {
+	.destroy	= armada_drm_slave_destroy,
+};
+
+static const struct drm_connector_helper_funcs armada_drm_slave_helper_funcs = {
+	.get_modes	= armada_drm_slave_get_modes,
+	.mode_valid	= armada_drm_slave_encoder_mode_valid,
+	.best_encoder	= armada_drm_connector_encoder,
+};
+
+static const struct drm_encoder_helper_funcs drm_slave_encoder_helpers = {
+	.dpms = drm_i2c_encoder_dpms,
+	.save = drm_i2c_encoder_save,
+	.restore = drm_i2c_encoder_restore,
+	.mode_fixup = drm_i2c_encoder_mode_fixup,
+	.prepare = drm_i2c_encoder_prepare,
+	.commit = drm_i2c_encoder_commit,
+	.mode_set = drm_i2c_encoder_mode_set,
+	.detect = drm_i2c_encoder_detect,
+};
+
+static int
+armada_drm_conn_slave_create(struct drm_connector *conn, const void *data)
+{
+	const struct armada_drm_slave_config *config = data;
+	struct drm_encoder_slave *slave;
+	struct i2c_adapter *adap;
+	int ret;
+
+	conn->interlace_allowed = config->interlace_allowed;
+	conn->doublescan_allowed = config->doublescan_allowed;
+	conn->polled = config->polled;
+
+	drm_connector_helper_add(conn, &armada_drm_slave_helper_funcs);
+
+	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
+	if (!slave)
+		return -ENOMEM;
+
+	slave->base.possible_crtcs = config->crtcs;
+
+	adap = i2c_get_adapter(config->i2c_adapter_id);
+	if (!adap) {
+		kfree(slave);
+		return -EPROBE_DEFER;
+	}
+
+	ret = drm_encoder_init(conn->dev, &slave->base,
+			       &armada_drm_slave_encoder_funcs,
+			       DRM_MODE_ENCODER_TMDS);
+	if (ret) {
+		DRM_ERROR("unable to init encoder\n");
+		i2c_put_adapter(adap);
+		kfree(slave);
+		return ret;
+	}
+
+	ret = drm_i2c_encoder_init(conn->dev, slave, adap, &config->info);
+	i2c_put_adapter(adap);
+	if (ret) {
+		DRM_ERROR("unable to init encoder slave\n");
+		armada_drm_slave_destroy(&slave->base);
+		return ret;
+	}
+
+	drm_encoder_helper_add(&slave->base, &drm_slave_encoder_helpers);
+
+	ret = slave->slave_funcs->create_resources(&slave->base, conn);
+	if (ret) {
+		armada_drm_slave_destroy(&slave->base);
+		return ret;
+	}
+
+	ret = drm_mode_connector_attach_encoder(conn, &slave->base);
+	if (ret) {
+		armada_drm_slave_destroy(&slave->base);
+		return ret;
+	}
+
+	conn->encoder = &slave->base;
+
+	return ret;
+}
+
+static const struct armada_output_type armada_drm_conn_slave = {
+	.connector_type	= DRM_MODE_CONNECTOR_HDMIA,
+	.create		= armada_drm_conn_slave_create,
+	.set_property	= armada_drm_slave_encoder_set_property,
+};
+
+int armada_drm_connector_slave_create(struct drm_device *dev,
+	const struct armada_drm_slave_config *config)
+{
+	return armada_output_create(dev, &armada_drm_conn_slave, config);
+}