1 /* 2 * linux/drivers/video/bt455.h 3 * 4 * Copyright 2003 Thiemo Seufer <[email protected]> 5 * Copyright 2016 Maciej W. Rozycki <[email protected]> 6 * 7 * This file is subject to the terms and conditions of the GNU General 8 * Public License. See the file COPYING in the main directory of this 9 * archive for more details. 10 */ 11 #include <linux/types.h> 12 13 /* 14 * Bt455 byte-wide registers, 32-bit aligned. 15 */ 16 struct 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 27 static inline void bt455_select_reg(struct bt455_regs *regs, int ir) 28 { 29 mb(); 30 regs->addr_cmap = ir & 0x0f; 31 } 32 33 /* 34 * Read/write to a Bt455 color map register. 35 */ 36 static inline void bt455_read_cmap_entry(struct bt455_regs *regs, 37 int cr, u8 *grey) 38 { 39 bt455_select_reg(regs, cr); 40 mb(); 41 regs->addr_cmap_data; 42 rmb(); 43 *grey = regs->addr_cmap_data & 0xf; 44 rmb(); 45 regs->addr_cmap_data; 46 } 47 48 static inline void bt455_write_cmap_entry(struct bt455_regs *regs, 49 int cr, u8 grey) 50 { 51 bt455_select_reg(regs, cr); 52 wmb(); 53 regs->addr_cmap_data = 0x0; 54 wmb(); 55 regs->addr_cmap_data = grey & 0xf; 56 wmb(); 57 regs->addr_cmap_data = 0x0; 58 } 59 60 static inline void bt455_write_ovly_entry(struct bt455_regs *regs, 61 int cr, u8 grey) 62 { 63 bt455_select_reg(regs, cr); 64 wmb(); 65 regs->addr_ovly = 0x0; 66 wmb(); 67 regs->addr_ovly = grey & 0xf; 68 wmb(); 69 regs->addr_ovly = 0x0; 70 } 71