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Diffstat (limited to 'arch/mips/ddb5xxx/ddb5477/lcd44780.c')
-rw-r--r--arch/mips/ddb5xxx/ddb5477/lcd44780.c92
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diff --git a/arch/mips/ddb5xxx/ddb5477/lcd44780.c b/arch/mips/ddb5xxx/ddb5477/lcd44780.c
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index 000000000000..35c6c22610c5
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+++ b/arch/mips/ddb5xxx/ddb5477/lcd44780.c
@@ -0,0 +1,92 @@
+/*
+ * lcd44780.c
+ * Simple "driver" for a memory-mapped 44780-style LCD display.
+ *
+ * Copyright 2001 Bradley D. LaRonde <brad@ltc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+#define LCD44780_COMMAND ((volatile unsigned char *)0xbe020000)
+#define LCD44780_DATA ((volatile unsigned char *)0xbe020001)
+
+#define LCD44780_4BIT_1LINE 0x20
+#define LCD44780_4BIT_2LINE 0x28
+#define LCD44780_8BIT_1LINE 0x30
+#define LCD44780_8BIT_2LINE 0x38
+#define LCD44780_MODE_DEC 0x04
+#define LCD44780_MODE_DEC_SHIFT 0x05
+#define LCD44780_MODE_INC 0x06
+#define LCD44780_MODE_INC_SHIFT 0x07
+#define LCD44780_SCROLL_LEFT 0x18
+#define LCD44780_SCROLL_RIGHT 0x1e
+#define LCD44780_CURSOR_UNDERLINE 0x0e
+#define LCD44780_CURSOR_BLOCK 0x0f
+#define LCD44780_CURSOR_OFF 0x0c
+#define LCD44780_CLEAR 0x01
+#define LCD44780_BLANK 0x08
+#define LCD44780_RESTORE 0x0c // Same as CURSOR_OFF
+#define LCD44780_HOME 0x02
+#define LCD44780_LEFT 0x10
+#define LCD44780_RIGHT 0x14
+
+void lcd44780_wait(void)
+{
+ int i, j;
+ for(i=0; i < 400; i++)
+ for(j=0; j < 10000; j++);
+}
+
+void lcd44780_command(unsigned char c)
+{
+ *LCD44780_COMMAND = c;
+ lcd44780_wait();
+}
+
+void lcd44780_data(unsigned char c)
+{
+ *LCD44780_DATA = c;
+ lcd44780_wait();
+}
+
+void lcd44780_puts(const char* s)
+{
+ int i,j;
+ int pos = 0;
+
+ lcd44780_command(LCD44780_CLEAR);
+ while(*s) {
+ lcd44780_data(*s);
+ s++;
+ pos++;
+ if (pos == 8) {
+ /* We must write 32 of spaces to get cursor to 2nd line */
+ for (j=0; j<32; j++) {
+ lcd44780_data(' ');
+ }
+ }
+ if (pos == 16) {
+ /* We have filled all 16 character positions, so stop
+ outputing data */
+ break;
+ }
+ }
+#ifdef LCD44780_PUTS_PAUSE
+ for(i = 1; i < 2000; i++)
+ lcd44780_wait();
+#endif
+}
+
+void lcd44780_init(void)
+{
+ // The display on the RockHopper is physically a single
+ // 16 char line (two 8 char lines concatenated). bdl
+ lcd44780_command(LCD44780_8BIT_2LINE);
+ lcd44780_command(LCD44780_MODE_INC);
+ lcd44780_command(LCD44780_CURSOR_BLOCK);
+ lcd44780_command(LCD44780_CLEAR);
+}