video: tegra: Move pin function to new util file

This will be used in forthcoming cursor support in addition to the
existing overlay flipping support.

bug 818525

Original-Change-Id: Ic27267deeaefad4ec803eb457a02b22c0d9a1373
Signed-off-by: Robert Morell <rmorell@nvidia.com>
Reviewed-on: http://git-master/r/40517
Reviewed-by: Varun Colbert <vcolbert@nvidia.com>
Tested-by: Varun Colbert <vcolbert@nvidia.com>

Rebase-Id: Rc1e18fe5248f9dfd1f9ee23184cd2c102539ca61

1 files changed, 78 insertions, 0 deletions

diff --git a/drivers/video/tegra/dc/ext/util.c b/drivers/video/tegra/dc/ext/util.c
new file mode 100644
index 000000000000..747085579f15
--- /dev/null
+++ b/drivers/video/tegra/dc/ext/util.c
@@ -0,0 +1,78 @@
+/*
+ * drivers/video/tegra/dc/ext/util.c
+ *
+ * Copyright (C) 2011, NVIDIA Corporation
+ *
+ * Author: Robert Morell <rmorell@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/err.h>
+#include <linux/types.h>
+
+#include <mach/dc.h>
+#include <mach/nvmap.h>
+
+/* ugh */
+#include "../../nvmap/nvmap.h"
+
+#include "tegra_dc_ext_priv.h"
+
+int tegra_dc_ext_pin_window(struct tegra_dc_ext_user *user, u32 id,
+			    struct nvmap_handle_ref **handle,
+			    dma_addr_t *phys_addr)
+{
+	struct tegra_dc_ext *ext = user->ext;
+	struct nvmap_handle_ref *win_dup;
+	struct nvmap_handle *win_handle;
+	dma_addr_t phys;
+
+	if (!id) {
+		*handle = NULL;
+		*phys_addr = -1;
+
+		return 0;
+	}
+
+	/*
+	 * Take a reference to the buffer using the user's nvmap context, to
+	 * make sure they have permissions to access it.
+	 */
+	win_handle = nvmap_get_handle_id(user->nvmap, id);
+	if (!win_handle)
+		return -EACCES;
+
+	/*
+	 * Duplicate the buffer's handle into the dc_ext driver's nvmap
+	 * context, to ensure that the handle won't be freed as long as it is
+	 * in use by display.
+	 */
+	win_dup = nvmap_duplicate_handle_id(ext->nvmap, id);
+
+	/* Release the reference we took in the user's context above */
+	nvmap_handle_put(win_handle);
+
+	if (IS_ERR(win_dup))
+		return PTR_ERR(win_dup);
+
+	phys = nvmap_pin(ext->nvmap, win_dup);
+	/* XXX this isn't correct for non-pointers... */
+	if (IS_ERR((void *)phys)) {
+		nvmap_free(ext->nvmap, win_dup);
+		return PTR_ERR((void *)phys);
+	}
+
+	*phys_addr = phys;
+	*handle = win_dup;
+
+	return 0;
+}