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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
commita9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch)
treecc62d74e0eb4905246978674461e78e2f9df2afd /drivers/video/fbdev/bt455.h
downloadlinux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz
linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'drivers/video/fbdev/bt455.h')
-rw-r--r--drivers/video/fbdev/bt455.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/drivers/video/fbdev/bt455.h b/drivers/video/fbdev/bt455.h
new file mode 100644
index 000000000..dd1404b40
--- /dev/null
+++ b/drivers/video/fbdev/bt455.h
@@ -0,0 +1,90 @@
+/*
+ * linux/drivers/video/bt455.h
+ *
+ * Copyright 2003 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>
+ * Copyright 2016 Maciej W. Rozycki <macro@linux-mips.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+#include <linux/types.h>
+
+/*
+ * Bt455 byte-wide registers, 32-bit aligned.
+ */
+struct bt455_regs {
+ volatile u8 addr_cmap;
+ u8 pad0[3];
+ volatile u8 addr_cmap_data;
+ u8 pad1[3];
+ volatile u8 addr_clr;
+ u8 pad2[3];
+ volatile u8 addr_ovly;
+ u8 pad3[3];
+};
+
+static inline void bt455_select_reg(struct bt455_regs *regs, int ir)
+{
+ mb();
+ regs->addr_cmap = ir & 0x0f;
+}
+
+static inline void bt455_reset_reg(struct bt455_regs *regs)
+{
+ mb();
+ regs->addr_clr = 0;
+}
+
+/*
+ * Read/write to a Bt455 color map register.
+ */
+static inline void bt455_read_cmap_next(struct bt455_regs *regs, u8 *grey)
+{
+ mb();
+ regs->addr_cmap_data;
+ rmb();
+ *grey = regs->addr_cmap_data & 0xf;
+ rmb();
+ regs->addr_cmap_data;
+}
+
+static inline void bt455_write_cmap_next(struct bt455_regs *regs, u8 grey)
+{
+ wmb();
+ regs->addr_cmap_data = 0x0;
+ wmb();
+ regs->addr_cmap_data = grey & 0xf;
+ wmb();
+ regs->addr_cmap_data = 0x0;
+}
+
+static inline void bt455_write_ovly_next(struct bt455_regs *regs, u8 grey)
+{
+ wmb();
+ regs->addr_ovly = 0x0;
+ wmb();
+ regs->addr_ovly = grey & 0xf;
+ wmb();
+ regs->addr_ovly = 0x0;
+}
+
+static inline void bt455_read_cmap_entry(struct bt455_regs *regs,
+ int cr, u8 *grey)
+{
+ bt455_select_reg(regs, cr);
+ bt455_read_cmap_next(regs, grey);
+}
+
+static inline void bt455_write_cmap_entry(struct bt455_regs *regs,
+ int cr, u8 grey)
+{
+ bt455_select_reg(regs, cr);
+ bt455_write_cmap_next(regs, grey);
+}
+
+static inline void bt455_write_ovly_entry(struct bt455_regs *regs, u8 grey)
+{
+ bt455_reset_reg(regs);
+ bt455_write_ovly_next(regs, grey);
+}