[PATCH 06/10] ARM: mx28: update clocks for dual fec support

Hello,

On Wed, Dec 29, 2010 at 06:14:42PM +0800, Shawn Guo wrote:

On Wed, Dec 29, 2010 at 09:10:44AM +0100, Uwe Kleine-K?nig wrote:

quoted

On Wed, Dec 29, 2010 at 08:57:34AM +0200, Baruch Siach wrote:

quoted

Hi Shawn,

On Tue, Dec 28, 2010 at 10:55:51PM +0800, Shawn Guo wrote:

quoted

* Change fec clock registration to use con_id only for looking up,
  so that dual fec driver can find the same clock for both fec0
  and fec1.

* Explicitly call clk_enable for some clocks that have been on to
  reflect the clock status and get usecount updated. Otherwise,
  clocks could be turned off by pair call of clk_enable/clk_disable
  in drivers, because of the incorrect initial usecount.

Signed-off-by: Shawn Guo <redacted>
---
 arch/arm/mach-mxs/clock-mx28.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-mxs/clock-mx28.c b/arch/arm/mach-mxs/clock-mx28.c
index dd6d158..6b77aff 100644
--- a/arch/arm/mach-mxs/clock-mx28.c
+++ b/arch/arm/mach-mxs/clock-mx28.c

@@ -603,7 +603,7 @@ _DEFINE_CLOCK(fec_clk, ENET, DISABLE, &hbus_clk);
 
 static struct clk_lookup lookups[] = {
 	_REGISTER_CLOCK("uart", NULL, uart_clk)
-	_REGISTER_CLOCK("fec.0", NULL, fec_clk)
+	_REGISTER_CLOCK(NULL, "fec_clk", fec_clk)

Looks like a wrong use of the clk API. You should define define two clocks 
"fec.0" and "fec.1".

The commit log suggests that both should enable the same (hardware)
clock.  Still I agree with Baruch that in this case clk_get() should
just return the same clock for both fec.0 and fec.1.
I think it's a bit more work than just adding
	_REGISTER_CLOCK("fec.1", NULL, fec_clk)

I originally had what you suggest above. But when I found fec driver
only calls clk_get like below, I change the code to current one to 
save one line code.

	fep->clk = clk_get(&pdev->dev, "fec_clk");

if there is only a single (software) clock for the fec, the driver
should pass NULL as 2nd argument to clk_get.

Best regards
Uwe

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