Re: [PATCH v2 02/18] dt-bindings: timer: sp804: add timer-width property

From: Robin Murphy
Date: Thu Mar 17 2016 - 14:06:18 EST

Hi Rob,

On 17/03/16 17:09, Rob Herring wrote:
On Wed, Mar 09, 2016 at 11:24:04AM +0100, Neil Armstrong wrote:
Add timer-width optional property to specify a different vendor
specific timer counter bit-width.

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Documentation/devicetree/bindings/timer/arm,sp804.txt | 2 ++
1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/timer/arm,sp804.txt b/Documentation/devicetree/bindings/timer/arm,sp804.txt
index 5cd8eee7..141e143 100644
--- a/Documentation/devicetree/bindings/timer/arm,sp804.txt
+++ b/Documentation/devicetree/bindings/timer/arm,sp804.txt
@@ -17,6 +17,8 @@ Optional properties:
- arm,sp804-has-irq = <#>: In the case of only 1 timer irq line connected, this
specifies if the irq connection is for timer 1 or timer 2. A value of 1
or 2 should be used.
+- arm,timer-width: Should contain the width in number of bits of the counter,
+ is considered by default 32 but can be changed for vendor variants.

That would not be an SP804 nor would the vendor be ARM in that case. So
add a new compatible string for the vendor that decided to hack up ARM's
IP block.

By all accounts this is some ancient reference design[1] which later evolved _into_ the SP804, so that vendor would probably still be ARM ;)

A separate compatible string would indeed make more sense, though. Both semantically and in terms of letting the driver account for the differences automatically.




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