drivers/video/bt455.h

   1 /*
   2  *      linux/drivers/video/bt455.h
   3  *
   4  *      Copyright 2003  Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>
   5  *
   6  *      This file is subject to the terms and conditions of the GNU General
   7  *      Public License. See the file COPYING in the main directory of this
   8  *      archive for more details.
   9  */
  10 #include <linux/types.h>
  11 #include <asm/system.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, int cr,
  37                                          u8* red, u8* green, u8* blue)
  38 {
  39         bt455_select_reg(regs, cr);
  40         mb();
  41         *red = regs->addr_cmap_data & 0x0f;
  42         rmb();
  43         *green = regs->addr_cmap_data & 0x0f;
  44         rmb();
  45         *blue = regs->addr_cmap_data & 0x0f;
  46 }
  47
  48 static inline void bt455_write_cmap_entry(struct bt455_regs *regs, int cr,
  49                                           u8 red, u8 green, u8 blue)
  50 {
  51         bt455_select_reg(regs, cr);
  52         wmb();
  53         regs->addr_cmap_data = red & 0x0f;
  54         wmb();
  55         regs->addr_cmap_data = green & 0x0f;
  56         wmb();
  57         regs->addr_cmap_data = blue & 0x0f;
  58 }
  59
  60 static inline void bt455_write_ovly_entry(struct bt455_regs *regs, int cr,
  61                                           u8 red, u8 green, u8 blue)
  62 {
  63         bt455_select_reg(regs, cr);
  64         wmb();
  65         regs->addr_ovly = red & 0x0f;
  66         wmb();
  67         regs->addr_ovly = green & 0x0f;
  68         wmb();
  69         regs->addr_ovly = blue & 0x0f;
  70 }
  71
  72 static inline void bt455_set_cursor(struct bt455_regs *regs)
  73 {
  74         mb();
  75         regs->addr_ovly = 0x0f;
  76         wmb();
  77         regs->addr_ovly = 0x0f;
  78         wmb();
  79         regs->addr_ovly = 0x0f;
  80 }
  81
  82 static inline void bt455_erase_cursor(struct bt455_regs *regs)
  83 {
  84         /* bt455_write_cmap_entry(regs, 8, 0x00, 0x00, 0x00); */
  85         /* bt455_write_cmap_entry(regs, 9, 0x00, 0x00, 0x00); */
  86         bt455_write_ovly_entry(regs, 8, 0x03, 0x03, 0x03);
  87         bt455_write_ovly_entry(regs, 9, 0x07, 0x07, 0x07);
  88
  89         wmb();
  90         regs->addr_ovly = 0x09;
  91         wmb();
  92         regs->addr_ovly = 0x09;
  93         wmb();
  94         regs->addr_ovly = 0x09;
  95 }