diff mbox

ARM: debug: Remove unsupported operand from Kconfig.debug

Message ID 1434306201-21840-1-git-send-email-linux@roeck-us.net (mailing list archive)
State New, archived
Headers show

Commit Message

Guenter Roeck June 14, 2015, 6:23 p.m. UTC
arm builds show the following warning.

arch/arm/Kconfig.debug:1576:warning: ignoring unsupported character '>'

This is due to

config DEBUG_UART_8250_WORD
	bool "Use 32-bit accesses for 8250 UART"
	depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
	depends on DEBUG_UART_8250_SHIFT >= 2

This may create the false expectation that DEBUG_UART_8250_WORD
is enabled if DEBUG_UART_8250_SHIFT is larger than 2, so drop the '>'.

Fixes: 0b4cccbec606 ("ARM: debug: add support for word accesses to
	debug/8250.S")
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 arch/arm/Kconfig.debug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Russell King - ARM Linux June 14, 2015, 7:13 p.m. UTC | #1
On Sun, Jun 14, 2015 at 11:23:21AM -0700, Guenter Roeck wrote:
> arm builds show the following warning.
> 
> arch/arm/Kconfig.debug:1576:warning: ignoring unsupported character '>'
> 
> This is due to
> 
> config DEBUG_UART_8250_WORD
> 	bool "Use 32-bit accesses for 8250 UART"
> 	depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
> 	depends on DEBUG_UART_8250_SHIFT >= 2
> 
> This may create the false expectation that DEBUG_UART_8250_WORD
> is enabled if DEBUG_UART_8250_SHIFT is larger than 2, so drop the '>'.

"is" ?  No, "depends" will control the visibility of this option.

You're quite right that it's expected that the option is visible if
DEBUG_UART_8250_SHIFT is greater than or equal to 2, and that's
actually exactly what we want to express here - and it's entirely
possible for someone to type in a shift greater than two, and that
would also be legal.

I guess if >= 2 doesn't work, what we need instead is:

	depends on DEBUG_UART_8250_SHIFT != 0 &&
		   DEBUG_UART_8250_SHIFT != 1

which would have the same effect.  I also guess that adding a
"range 0 31" or similar to the DEBUG_UART_8250_SHIFT option would
also be a good idea.

Patches to that effect welcome.

Thanks.
diff mbox

Patch

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index f1b157971366..f0655c9350bf 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -1573,7 +1573,7 @@  config DEBUG_UART_8250_SHIFT
 config DEBUG_UART_8250_WORD
 	bool "Use 32-bit accesses for 8250 UART"
 	depends on DEBUG_LL_UART_8250 || DEBUG_UART_8250
-	depends on DEBUG_UART_8250_SHIFT >= 2
+	depends on DEBUG_UART_8250_SHIFT = 2
 	default y if DEBUG_PICOXCELL_UART || DEBUG_SOCFPGA_UART0 || \
 		DEBUG_SOCFPGA_UART1 || ARCH_KEYSTONE || \
 		DEBUG_ALPINE_UART0 || \