i2c-parport: Fix a minor race on driver unload

When unloading the driver, we really want to unregister the i2c adapter
before we power it off, rather than the other way around.

Also speed up the bus a bit when we can sense SCL. The slaves will
stretch the line as needed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>

drivers/i2c/busses/i2c-parport.c

 /* ------------------------------------------------------------------------ *
  * i2c-parport.c I2C bus over parallel port                                 *
  * ------------------------------------------------------------------------ *
-   Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
+   Copyright (C) 2003-2007 Jean Delvare <khali@linux-fr.org>
    
    Based on older i2c-philips-par.c driver
    Copyright (C) 1995-2000 Simon G. Vogl
@@ -137,7 +137,7 @@ static struct i2c_algo_bit_data parport_algo_data = {
 	.setscl		= parport_setscl,
 	.getsda		= parport_getsda,
 	.getscl		= parport_getscl,
-	.udelay		= 60,
+	.udelay		= 10, /* ~50 kbps */
 	.timeout	= HZ,
 }; 
 
@@ -168,8 +168,11 @@ static void i2c_parport_attach (struct parport *port)
 	strlcpy(adapter->adapter.name, "Parallel port adapter",
 		sizeof(adapter->adapter.name));
 	adapter->algo_data = parport_algo_data;
-	if (!adapter_parm[type].getscl.val)
+	/* Slow down if we can't sense SCL */
+	if (!adapter_parm[type].getscl.val) {
 		adapter->algo_data.getscl = NULL;
+		adapter->algo_data.udelay = 50; /* ~10 kbps */
+	}
 	adapter->algo_data.data = port;
 	adapter->adapter.algo_data = &adapter->algo_data;
 
@@ -211,11 +214,12 @@ static void i2c_parport_detach (struct parport *port)
 	for (prev = NULL, adapter = adapter_list; adapter;
 	     prev = adapter, adapter = adapter->next) {
 		if (adapter->pdev->port == port) {
+			i2c_del_adapter(&adapter->adapter);
+
 			/* Un-init if needed (power off...) */
 			if (adapter_parm[type].init.val)
 				line_set(port, 0, &adapter_parm[type].init);
 				
-			i2c_del_adapter(&adapter->adapter);
 			parport_unregister_device(adapter->pdev);
 			if (prev)
 				prev->next = adapter->next;