parisc: KittyHawk LCD fix

K class aka KittyHawk don't have LED support on their LCD. Installing
HP-UX confirmed this. The current led_wq fills the LCD with black
characters each time it runs.

The patch prevents the led_wq workqueue and its proc entry to be
created for KittyHawk machines.

It also increase min_cmd_delay as currently, one character out of two
is lost when a string is sent to the LCD.

Signed-off-by: Guy Martin <[e-mail]>
Signed-off-by: Kyle McMartin <kyle@mcmartin.c>

drivers/parisc/led.c

···
 static unsigned int led_lanrxtx   __read_mostly = 1;
 static char lcd_text[32]          __read_mostly;
 static char lcd_text_default[32]  __read_mostly;
+static int  lcd_no_led_support    __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */
 
 
 static struct workqueue_struct *led_wq;
···
 	.lcd_width =		16,
 	.lcd_cmd_reg_addr =	KITTYHAWK_LCD_CMD,
 	.lcd_data_reg_addr =	KITTYHAWK_LCD_DATA,
-	.min_cmd_delay =	40,
+	.min_cmd_delay =	80,
 	.reset_cmd1 =		0x80,
 	.reset_cmd2 =		0xc0,
 };
···
 {	
 	/* Display the default text now */
 	if (led_type == LED_HASLCD) lcd_print( lcd_text_default );
+
+	/* KittyHawk has no LED support on its LCD */
+	if (lcd_no_led_support) return 0;
 
 	/* Create the work queue and queue the LED task */
 	led_wq = create_singlethread_workqueue("led_wq");	
···
 
 	proc_pdc_root = proc_mkdir("pdc", 0);
 	if (!proc_pdc_root) return -1;
-	ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
-				&led_proc_fops, (void *)LED_NOLCD); /* LED */
-	if (!ent) return -1;
+
+	if (!lcd_no_led_support)
+	{
+		ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
+					&led_proc_fops, (void *)LED_NOLCD); /* LED */
+		if (!ent) return -1;
+	}
 
 	if (led_type == LED_HASLCD)
 	{
···
 	case 0x58B:		/* KittyHawk DC2 100 (K200) */
 		printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
 				"LED detection skipped.\n", __FILE__, CPU_HVERSION);
+		lcd_no_led_support = 1;
 		goto found;	/* use the preinitialized values of lcd_info */
 	}