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Diffstat (limited to 'arch/xtensa/platforms/xtfpga/lcd.c')
-rw-r--r--arch/xtensa/platforms/xtfpga/lcd.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/xtensa/platforms/xtfpga/lcd.c b/arch/xtensa/platforms/xtfpga/lcd.c
new file mode 100644
index 000000000000..2872301598df
--- /dev/null
+++ b/arch/xtensa/platforms/xtfpga/lcd.c
@@ -0,0 +1,76 @@
+/*
+ * Driver for the LCD display on the Tensilica LX60 Board.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001, 2006 Tensilica Inc.
+ */
+
+/*
+ *
+ * FIXME: this code is from the examples from the LX60 user guide.
+ *
+ * The lcd_pause function does busy waiting, which is probably not
+ * great. Maybe the code could be changed to use kernel timers, or
+ * change the hardware to not need to wait.
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+
+#include <platform/hardware.h>
+#include <platform/lcd.h>
+#include <linux/delay.h>
+
+#define LCD_PAUSE_ITERATIONS 4000
+#define LCD_CLEAR 0x1
+#define LCD_DISPLAY_ON 0xc
+
+/* 8bit and 2 lines display */
+#define LCD_DISPLAY_MODE8BIT 0x38
+#define LCD_DISPLAY_POS 0x80
+#define LCD_SHIFT_LEFT 0x18
+#define LCD_SHIFT_RIGHT 0x1c
+
+static int __init lcd_init(void)
+{
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ mdelay(5);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ udelay(200);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ udelay(50);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_ON;
+ udelay(50);
+ *LCD_INSTR_ADDR = LCD_CLEAR;
+ mdelay(10);
+ lcd_disp_at_pos("XTENSA LINUX", 0);
+ return 0;
+}
+
+void lcd_disp_at_pos(char *str, unsigned char pos)
+{
+ *LCD_INSTR_ADDR = LCD_DISPLAY_POS | pos;
+ udelay(100);
+ while (*str != 0) {
+ *LCD_DATA_ADDR = *str;
+ udelay(200);
+ str++;
+ }
+}
+
+void lcd_shiftleft(void)
+{
+ *LCD_INSTR_ADDR = LCD_SHIFT_LEFT;
+ udelay(50);
+}
+
+void lcd_shiftright(void)
+{
+ *LCD_INSTR_ADDR = LCD_SHIFT_RIGHT;
+ udelay(50);
+}
+
+arch_initcall(lcd_init);