[PATCH] serial: fix port type conflict between NS16550A & U6_16550A

[PATCH] serial: fix port type conflict between NS16550A & U6_16550A

[Philippe Langlais]

Bug seen by Dr. David Alan Gilbert with sparse

Signed-off-by: Philippe Langlais <philippe.langlais@stericsson.com>
---
 include/linux/serial.h      |    3 +--
 include/linux/serial_core.h |    3 ++-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/serial.h b/include/linux/serial.h
index 06c99b6..c8613c3 100644
--- a/include/linux/serial.h
+++ b/include/linux/serial.h
@@ -77,8 +77,7 @@ struct serial_struct {
 #define PORT_16654	11
 #define PORT_16850	12
 #define PORT_RSA	13	/* RSA-DV II/S card */
-#define PORT_U6_16550A	14
-#define PORT_MAX	14
+#define PORT_MAX	13
 
 #define SERIAL_IO_PORT	0
 #define SERIAL_IO_HUB6	1
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 119354f..6513f27 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -44,7 +44,8 @@
 #define PORT_RM9000	16	/* PMC-Sierra RM9xxx internal UART */
 #define PORT_OCTEON	17	/* Cavium OCTEON internal UART */
 #define PORT_AR7	18	/* Texas Instruments AR7 internal UART */
-#define PORT_MAX_8250	18	/* max port ID */
+#define PORT_U6_16550A	19	/* ST-Ericsson U6xxx internal UART */
+#define PORT_MAX_8250	19	/* max port ID */
 
 /*
  * ARM specific type numbers.  These are not currently guaranteed
-- 
1.7.2.2

Re: [PATCH] serial: fix port type conflict between NS16550A & U6_16550A

[Greg KH]

On Tue, Aug 31, 2010 at 02:19:09PM +0200, Philippe Langlais wrote:
> Bug seen by Dr. David Alan Gilbert with sparse

sparse found this?  nice.

But odds are we should switch this to an enum to try to find it earlier,
right?

I'll go queue this up.

thanks,

greg k-h

Re: [PATCH] serial: fix port type conflict between NS16550A & U6_16550A

[Dr. David Alan Gilbert]

* Greg KH (gregkh@suse.de) wrote:
> On Tue, Aug 31, 2010 at 02:19:09PM +0200, Philippe Langlais wrote:
> > Bug seen by Dr. David Alan Gilbert with sparse
> 
> sparse found this?  nice.

It spotted it because it ended up causing the same element of the array
to be initialised twice.
A few hours spent playing with sparse has spotted some nice easy-to-fix
thinko type bugs (this one, two parameters being swapped to kzalloc,
a few places where people passed enums in place of bools).   Basically
if you ignore all the address space, static and locking output
whats left is 'odd' stuff that appears to be worthy of a read.
(That's from my first time using it).  They're all the class of problems
that you would hope a type system in the compiler would spot.

> But odds are we should switch this to an enum to try to find it earlier,
> right?

An enum would be nice; but the other problem is that there are two
lists one in serial.h and one in serial_core.h that both start
in the same way - it was just a matter of time until something
got added to the wrong one. IMO the older list needs killing
unless there is a very good reason for it.

Dave
-- 
 -----Open up your eyes, open up your mind, open up your code -------   
/ Dr. David Alan Gilbert    |       Running GNU/Linux       | Happy  \ 
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