linux/drivers/char/lcd.c
Arnd Bergmann 600bf8140c lcd: BKL pushdown
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2008-06-20 14:05:58 -06:00

517 lines
9.6 KiB
C

/*
* LCD, LED and Button interface for Cobalt
*
* 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) 1996, 1997 by Andrew Bose
*
* Linux kernel version history:
* March 2001: Ported from 2.0.34 by Liam Davies
*
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/fcntl.h>
#include <linux/mc146818rtc.h>
#include <linux/netdevice.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include "lcd.h"
static int lcd_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
static unsigned int lcd_present = 1;
/* used in arch/mips/cobalt/reset.c */
int led_state = 0;
#if defined(CONFIG_TULIP) && 0
#define MAX_INTERFACES 8
static linkcheck_func_t linkcheck_callbacks[MAX_INTERFACES];
static void *linkcheck_cookies[MAX_INTERFACES];
int lcd_register_linkcheck_func(int iface_num, void *func, void *cookie)
{
if (iface_num < 0 ||
iface_num >= MAX_INTERFACES ||
linkcheck_callbacks[iface_num] != NULL)
return -1;
linkcheck_callbacks[iface_num] = (linkcheck_func_t) func;
linkcheck_cookies[iface_num] = cookie;
return 0;
}
#endif
static int lcd_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct lcd_display button_display;
unsigned long address, a;
switch (cmd) {
case LCD_On:
udelay(150);
BusyCheck();
LCDWriteInst(0x0F);
break;
case LCD_Off:
udelay(150);
BusyCheck();
LCDWriteInst(0x08);
break;
case LCD_Reset:
udelay(150);
LCDWriteInst(0x3F);
udelay(150);
LCDWriteInst(0x3F);
udelay(150);
LCDWriteInst(0x3F);
udelay(150);
LCDWriteInst(0x3F);
udelay(150);
LCDWriteInst(0x01);
udelay(150);
LCDWriteInst(0x06);
break;
case LCD_Clear:
udelay(150);
BusyCheck();
LCDWriteInst(0x01);
break;
case LCD_Cursor_Left:
udelay(150);
BusyCheck();
LCDWriteInst(0x10);
break;
case LCD_Cursor_Right:
udelay(150);
BusyCheck();
LCDWriteInst(0x14);
break;
case LCD_Cursor_Off:
udelay(150);
BusyCheck();
LCDWriteInst(0x0C);
break;
case LCD_Cursor_On:
udelay(150);
BusyCheck();
LCDWriteInst(0x0F);
break;
case LCD_Blink_Off:
udelay(150);
BusyCheck();
LCDWriteInst(0x0E);
break;
case LCD_Get_Cursor_Pos:{
struct lcd_display display;
udelay(150);
BusyCheck();
display.cursor_address = (LCDReadInst);
display.cursor_address =
(display.cursor_address & 0x07F);
if (copy_to_user
((struct lcd_display *) arg, &display,
sizeof(struct lcd_display)))
return -EFAULT;
break;
}
case LCD_Set_Cursor_Pos:{
struct lcd_display display;
if (copy_from_user
(&display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
a = (display.cursor_address | kLCD_Addr);
udelay(150);
BusyCheck();
LCDWriteInst(a);
break;
}
case LCD_Get_Cursor:{
struct lcd_display display;
udelay(150);
BusyCheck();
display.character = LCDReadData;
if (copy_to_user
((struct lcd_display *) arg, &display,
sizeof(struct lcd_display)))
return -EFAULT;
udelay(150);
BusyCheck();
LCDWriteInst(0x10);
break;
}
case LCD_Set_Cursor:{
struct lcd_display display;
if (copy_from_user
(&display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
udelay(150);
BusyCheck();
LCDWriteData(display.character);
udelay(150);
BusyCheck();
LCDWriteInst(0x10);
break;
}
case LCD_Disp_Left:
udelay(150);
BusyCheck();
LCDWriteInst(0x18);
break;
case LCD_Disp_Right:
udelay(150);
BusyCheck();
LCDWriteInst(0x1C);
break;
case LCD_Home:
udelay(150);
BusyCheck();
LCDWriteInst(0x02);
break;
case LCD_Write:{
struct lcd_display display;
unsigned int index;
if (copy_from_user
(&display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
udelay(150);
BusyCheck();
LCDWriteInst(0x80);
udelay(150);
BusyCheck();
for (index = 0; index < (display.size1); index++) {
udelay(150);
BusyCheck();
LCDWriteData(display.line1[index]);
BusyCheck();
}
udelay(150);
BusyCheck();
LCDWriteInst(0xC0);
udelay(150);
BusyCheck();
for (index = 0; index < (display.size2); index++) {
udelay(150);
BusyCheck();
LCDWriteData(display.line2[index]);
}
break;
}
case LCD_Read:{
struct lcd_display display;
BusyCheck();
for (address = kDD_R00; address <= kDD_R01;
address++) {
a = (address | kLCD_Addr);
udelay(150);
BusyCheck();
LCDWriteInst(a);
udelay(150);
BusyCheck();
display.line1[address] = LCDReadData;
}
display.line1[0x27] = '\0';
for (address = kDD_R10; address <= kDD_R11;
address++) {
a = (address | kLCD_Addr);
udelay(150);
BusyCheck();
LCDWriteInst(a);
udelay(150);
BusyCheck();
display.line2[address - 0x40] =
LCDReadData;
}
display.line2[0x27] = '\0';
if (copy_to_user
((struct lcd_display *) arg, &display,
sizeof(struct lcd_display)))
return -EFAULT;
break;
}
// set all GPIO leds to led_display.leds
case LED_Set:{
struct lcd_display led_display;
if (copy_from_user
(&led_display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
led_state = led_display.leds;
LEDSet(led_state);
break;
}
// set only bit led_display.leds
case LED_Bit_Set:{
unsigned int i;
int bit = 1;
struct lcd_display led_display;
if (copy_from_user
(&led_display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
for (i = 0; i < (int) led_display.leds; i++) {
bit = 2 * bit;
}
led_state = led_state | bit;
LEDSet(led_state);
break;
}
// clear only bit led_display.leds
case LED_Bit_Clear:{
unsigned int i;
int bit = 1;
struct lcd_display led_display;
if (copy_from_user
(&led_display, (struct lcd_display *) arg,
sizeof(struct lcd_display)))
return -EFAULT;
for (i = 0; i < (int) led_display.leds; i++) {
bit = 2 * bit;
}
led_state = led_state & ~bit;
LEDSet(led_state);
break;
}
case BUTTON_Read:{
button_display.buttons = GPIRead;
if (copy_to_user
((struct lcd_display *) arg, &button_display,
sizeof(struct lcd_display)))
return -EFAULT;
break;
}
case LINK_Check:{
button_display.buttons =
*((volatile unsigned long *) (0xB0100060));
if (copy_to_user
((struct lcd_display *) arg, &button_display,
sizeof(struct lcd_display)))
return -EFAULT;
break;
}
case LINK_Check_2:{
int iface_num;
/* panel-utils should pass in the desired interface status is wanted for
* in "buttons" of the structure. We will set this to non-zero if the
* link is in fact up for the requested interface. --DaveM
*/
if (copy_from_user
(&button_display, (struct lcd_display *) arg,
sizeof(button_display)))
return -EFAULT;
iface_num = button_display.buttons;
#if defined(CONFIG_TULIP) && 0
if (iface_num >= 0 &&
iface_num < MAX_INTERFACES &&
linkcheck_callbacks[iface_num] != NULL) {
button_display.buttons =
linkcheck_callbacks[iface_num]
(linkcheck_cookies[iface_num]);
} else
#endif
button_display.buttons = 0;
if (__copy_to_user
((struct lcd_display *) arg, &button_display,
sizeof(struct lcd_display)))
return -EFAULT;
break;
}
default:
return -EINVAL;
}
return 0;
}
static int lcd_open(struct inode *inode, struct file *file)
{
cycle_kernel_lock();
if (!lcd_present)
return -ENXIO;
else
return 0;
}
/* Only RESET or NEXT counts as button pressed */
static inline int button_pressed(void)
{
unsigned long buttons = GPIRead;
if ((buttons == BUTTON_Next) || (buttons == BUTTON_Next_B)
|| (buttons == BUTTON_Reset_B))
return buttons;
return 0;
}
/* LED daemon sits on this and we wake him up once a key is pressed. */
static int lcd_waiters = 0;
static ssize_t lcd_read(struct file *file, char *buf,
size_t count, loff_t *ofs)
{
long buttons_now;
if (lcd_waiters > 0)
return -EINVAL;
lcd_waiters++;
while (((buttons_now = (long) button_pressed()) == 0) &&
!(signal_pending(current))) {
msleep_interruptible(2000);
}
lcd_waiters--;
if (signal_pending(current))
return -ERESTARTSYS;
return buttons_now;
}
/*
* The various file operations we support.
*/
static const struct file_operations lcd_fops = {
.read = lcd_read,
.ioctl = lcd_ioctl,
.open = lcd_open,
};
static struct miscdevice lcd_dev = {
MISC_DYNAMIC_MINOR,
"lcd",
&lcd_fops
};
static int lcd_init(void)
{
int ret;
unsigned long data;
pr_info("%s\n", LCD_DRIVER);
ret = misc_register(&lcd_dev);
if (ret) {
printk(KERN_WARNING LCD "Unable to register misc device.\n");
return ret;
}
/* Check region? Naaah! Just snarf it up. */
/* request_region(RTC_PORT(0), RTC_IO_EXTENT, "lcd");*/
udelay(150);
data = LCDReadData;
if ((data & 0x000000FF) == (0x00)) {
lcd_present = 0;
pr_info(LCD "LCD Not Present\n");
} else {
lcd_present = 1;
WRITE_GAL(kGal_DevBank2PReg, kGal_DevBank2Cfg);
WRITE_GAL(kGal_DevBank3PReg, kGal_DevBank3Cfg);
}
return 0;
}
static void __exit lcd_exit(void)
{
misc_deregister(&lcd_dev);
}
module_init(lcd_init);
module_exit(lcd_exit);
MODULE_AUTHOR("Andrew Bose");
MODULE_LICENSE("GPL");