diff options
Diffstat (limited to 'arch/xtensa/platforms/xtfpga/lcd.c')
-rw-r--r-- | arch/xtensa/platforms/xtfpga/lcd.c | 76 |
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 00000000000..2872301598d --- /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); |