linux-kernel - Re: [PATCH V2 3/3] nvmem: imx-ocotp: handling clock

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Date:	Mon, 9 May 2016 20:41:43 +0800
From:	Peng Fan <van.freenix@...il.com>
To:	Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
Cc:	shawnguo@...nel.org, maxime.ripard@...e-electrons.com,
	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH V2 3/3] nvmem: imx-ocotp: handling clock

Hi Srinivas,

On Mon, May 09, 2016 at 01:28:14PM +0100, Srinivas Kandagatla wrote:
>Thanks for the Ping, I totally missed this thread.
>
>On 20/04/16 18:26, Peng Fan wrote:
>>Before access ocotp nvmem area, the clock should be enabled.
>>Or, `hexdump nvmem` will hang the system. So, use such flow:
>>"
>>   1. clock_enable_prepare
>>   2. read nvmem ocotp area
>>   3. clock_disable_unprepare
>>"
>>
>>Signed-off-by: Peng Fan <van.freenix@...il.com>
>>Cc: Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
>>Cc: Maxime Ripard <maxime.ripard@...e-electrons.com>
>>Cc: Shawn Guo <shawnguo@...nel.org>
>>---
>>
>>V2:
>>  Follow Fabio's comments, check return value of clk_prepare_enable
>>
>>  drivers/nvmem/imx-ocotp.c | 16 +++++++++++++++-
>>  1 file changed, 15 insertions(+), 1 deletion(-)
>
>Changes to the driver looks good to me,
>Only one comment, As the clock property is now made mandatory, you should
>update the dt-bindings with this info too.

In Documentation/devicetree/bindings/nvmem/imx-ocotp.txt,
the clock property is already marked Required properties:
"
Required properties:
- compatible: should be one of
	"fsl,imx6q-ocotp" (i.MX6Q/D/DL/S),
	"fsl,imx6sl-ocotp" (i.MX6SL), or
	"fsl,imx6sx-ocotp" (i.MX6SX), followed by "syscon".
- reg: Should contain the register base and length.
- clocks: Should contain a phandle pointing to the gated peripheral clock.

Example:

	ocotp: ocotp@...bc000 {
		compatible = "fsl,imx6q-ocotp", "syscon";
		reg = <0x021bc000 0x4000>;
		clocks = <&clks IMX6QDL_CLK_IIM>;
	};
"

I think I do not need to update it, since it's already there -:)

Thanks,
Peng.
>
>
>thanks,
>srini