a bug in 8250.c

a bug in 8250.c

[Hu Gang]

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Hi Russell King:

In serial8250_request_std_resource@825.c, if all is pass it return 0, or failed return -XX, But you use 
        ret = serial8250_request_std_resource(up, &res_std);
->      if (ret)
                return;
I'm guess it use as . 
->      if (ret == 0) 

After change code, 2.5.39 Can found my modem.
Please check, If not proble, Please apply.
--------------
Here is the patch.
--- 8250.c	Sat Sep 28 11:15:16 2002
+++ 8250.c~fix	Sat Sep 28 22:07:36 2002
@@ -1564,7 +1564,7 @@
 
 	if (up->port.type == PORT_RSA) {
 		ret = serial8250_request_rsa_resource(up, &res_rsa);
-		if (ret)
+		if (ret == 0)
 			return ret;
 	}
 
@@ -1611,11 +1611,11 @@
 	 * tells us whether we can probe for the type of port.
 	 */
 	ret = serial8250_request_std_resource(up, &res_std);
-	if (ret)
+	if (ret == 0)
 		return;
 
 	ret = serial8250_request_rsa_resource(up, &res_rsa);
-	if (ret)
+	if (ret == 0)
 		probeflags &= ~PROBE_RSA;
 
 	if (flags & UART_CONFIG_TYPE)


-- 
		- Hu Gang



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Re: a bug in 8250.c

[Russell King]

On Sun, Sep 29, 2002 at 10:15:23AM +0800, Hu Gang wrote:
> In serial8250_request_std_resource@825.c, if all is pass it return 0, or failed return -XX, But you use 
>         ret = serial8250_request_std_resource(up, &res_std);
> ->      if (ret)
>                 return;
> I'm guess it use as . 
> ->      if (ret == 0) 

This is very wrong.

If we claim the resource, we fail in this function.  If we don't claim,
we succeed.

> After change code, 2.5.39 Can found my modem.

I guess you've got a resource clash.  Can you remove this patch from your
system, and then send the kernel boot messages, and the contents of
/proc/iomem and /proc/ioports please.

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html