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1/*2 * linux/drivers/video/bt455.h3 *4 * Copyright 2003 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>5 * Copyright 2016 Maciej W. Rozycki <macro@linux-mips.org>6 *7 * This file is subject to the terms and conditions of the GNU General8 * Public License. See the file COPYING in the main directory of this9 * archive for more details.10 */11#include <linux/types.h>12 13/*14 * Bt455 byte-wide registers, 32-bit aligned.15 */16struct bt455_regs {17 volatile u8 addr_cmap;18 u8 pad0[3];19 volatile u8 addr_cmap_data;20 u8 pad1[3];21 volatile u8 addr_clr;22 u8 pad2[3];23 volatile u8 addr_ovly;24 u8 pad3[3];25};26 27static inline void bt455_select_reg(struct bt455_regs *regs, int ir)28{29 mb();30 regs->addr_cmap = ir & 0x0f;31}32 33static inline void bt455_reset_reg(struct bt455_regs *regs)34{35 mb();36 regs->addr_clr = 0;37}38 39/*40 * Read/write to a Bt455 color map register.41 */42static inline void bt455_read_cmap_next(struct bt455_regs *regs, u8 *grey)43{44 mb();45 regs->addr_cmap_data;46 rmb();47 *grey = regs->addr_cmap_data & 0xf;48 rmb();49 regs->addr_cmap_data;50}51 52static inline void bt455_write_cmap_next(struct bt455_regs *regs, u8 grey)53{54 wmb();55 regs->addr_cmap_data = 0x0;56 wmb();57 regs->addr_cmap_data = grey & 0xf;58 wmb();59 regs->addr_cmap_data = 0x0;60}61 62static inline void bt455_write_ovly_next(struct bt455_regs *regs, u8 grey)63{64 wmb();65 regs->addr_ovly = 0x0;66 wmb();67 regs->addr_ovly = grey & 0xf;68 wmb();69 regs->addr_ovly = 0x0;70}71 72static inline void bt455_read_cmap_entry(struct bt455_regs *regs,73 int cr, u8 *grey)74{75 bt455_select_reg(regs, cr);76 bt455_read_cmap_next(regs, grey);77}78 79static inline void bt455_write_cmap_entry(struct bt455_regs *regs,80 int cr, u8 grey)81{82 bt455_select_reg(regs, cr);83 bt455_write_cmap_next(regs, grey);84}85 86static inline void bt455_write_ovly_entry(struct bt455_regs *regs, u8 grey)87{88 bt455_reset_reg(regs);89 bt455_write_ovly_next(regs, grey);90}91