On Tue, March 20, 2012 12:19 am, Sascha Hauer wrote:

On Mon, Mar 19, 2012 at 08:38:25PM -0700, Saravana Kannan wrote:

quoted

If memory allocation for the parents array or the parent string fails,
then
fail the registration immediately instead of calling clk_register and
hoping it fails there.

Return -ENOMEM on failure.

Signed-off-by: Saravana Kannan <redacted>
Cc: Mike Turquette <redacted>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Rob Herring <redacted>
Cc: Russell King <redacted>
Cc: Jeremy Kerr <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Arnd Bergman <redacted>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <redacted>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jamie Iles <redacted>
Cc: Richard Zhao <redacted>
Cc: Saravana Kannan <redacted>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <redacted>
Cc: Linus Walleij <redacted>
Cc: Stephen Boyd <redacted>
Cc: Amit Kucheria <redacted>
Cc: Deepak Saxena <redacted>
Cc: Grant Likely <redacted>
---
There are still some memory free issues when clk_register() fails, but I
will
fix it when I fixed the other register() fns to return ENOMEM of alloc
failure instead of a NULL.

 drivers/clk/clk-fixed-rate.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/clk-fixed-rate.c b/drivers/clk/clk-fixed-rate.c
index 90c79fb..6423ae9 100644
--- a/drivers/clk/clk-fixed-rate.c
+++ b/drivers/clk/clk-fixed-rate.c

@@ -61,22 +61,26 @@ struct clk *clk_register_fixed_rate(struct device

*dev, const char *name,
 		parent_names = kmalloc(sizeof(char *), GFP_KERNEL);

 		if (! parent_names)
-			goto out;
+			goto fail_ptr;

 		len = sizeof(char) * strlen(parent_name);

 		parent_names[0] = kmalloc(len, GFP_KERNEL);

 		if (!parent_names[0])
-			goto out;
+			goto fail_str;

 		strncpy(parent_names[0], parent_name, len);
 	}

It's easier to add a char *parent to struct clk_fixed and pass it to
clk_register with &fixed->parent. This saves you a kmalloc call and
makes the error path simpler. It's the same way already done in the
divider.

I thought about that since I saw the same was done for gated and divider
(I think). Here is my guess at Mike's reasoning for this:

Gated and divider clocks have to have a parent. There's nothing to gate
otherwise. But fixed rate clocks might not have a parent. It could be XO's
or PLLs running off of always on XOs not controlled by the SoC. So, it's
arguable to not have a parent. I don't have a strong opinion on this --
since Mike took the time to write it, it left it to his subjective
preference.

I sent this patch first since it was around the place I was cleaning up. I
didn't want to actually just shuffle around a bug. As I mentioned, this
patch still leaves a bug open -- what if clk_register() fails. I plan to
fix that once my two patches are picked up (hopefully).

Thanks,
Saravana

-- 
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