drivers/video/fbdev/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
  12 /*
  13  * Bt455 byte-wide registers, 32-bit aligned.
  14  */
  15 struct bt455_regs {
  16         volatile u8 addr_cmap;
  17         u8 pad0[3];
  18         volatile u8 addr_cmap_data;
  19         u8 pad1[3];
  20         volatile u8 addr_clr;
  21         u8 pad2[3];
  22         volatile u8 addr_ovly;
  23         u8 pad3[3];
  24 };
  25
  26 static inline void bt455_select_reg(struct bt455_regs *regs, int ir)
  27 {
  28         mb();
  29         regs->addr_cmap = ir & 0x0f;
  30 }
  31
  32 /*
  33  * Read/write to a Bt455 color map register.
  34  */
  35 static inline void bt455_read_cmap_entry(struct bt455_regs *regs, int cr,
  36                                          u8* red, u8* green, u8* blue)
  37 {
  38         bt455_select_reg(regs, cr);
  39         mb();
  40         *red = regs->addr_cmap_data & 0x0f;
  41         rmb();
  42         *green = regs->addr_cmap_data & 0x0f;
  43         rmb();
  44         *blue = regs->addr_cmap_data & 0x0f;
  45 }
  46
  47 static inline void bt455_write_cmap_entry(struct bt455_regs *regs, int cr,
  48                                           u8 red, u8 green, u8 blue)
  49 {
  50         bt455_select_reg(regs, cr);
  51         wmb();
  52         regs->addr_cmap_data = red & 0x0f;
  53         wmb();
  54         regs->addr_cmap_data = green & 0x0f;
  55         wmb();
  56         regs->addr_cmap_data = blue & 0x0f;
  57 }
  58
  59 static inline void bt455_write_ovly_entry(struct bt455_regs *regs, int cr,
  60                                           u8 red, u8 green, u8 blue)
  61 {
  62         bt455_select_reg(regs, cr);
  63         wmb();
  64         regs->addr_ovly = red & 0x0f;
  65         wmb();
  66         regs->addr_ovly = green & 0x0f;
  67         wmb();
  68         regs->addr_ovly = blue & 0x0f;
  69 }
  70
  71 static inline void bt455_set_cursor(struct bt455_regs *regs)
  72 {
  73         mb();
  74         regs->addr_ovly = 0x0f;
  75         wmb();
  76         regs->addr_ovly = 0x0f;
  77         wmb();
  78         regs->addr_ovly = 0x0f;
  79 }
  80
  81 static inline void bt455_erase_cursor(struct bt455_regs *regs)
  82 {
  83         /* bt455_write_cmap_entry(regs, 8, 0x00, 0x00, 0x00); */
  84         /* bt455_write_cmap_entry(regs, 9, 0x00, 0x00, 0x00); */
  85         bt455_write_ovly_entry(regs, 8, 0x03, 0x03, 0x03);
  86         bt455_write_ovly_entry(regs, 9, 0x07, 0x07, 0x07);
  87
  88         wmb();
  89         regs->addr_ovly = 0x09;
  90         wmb();
  91         regs->addr_ovly = 0x09;
  92         wmb();
  93         regs->addr_ovly = 0x09;
  94 }