Re: [PATCH] i2c: mv64xxx: Fix compilation breakage

Paul Gortmaker
2014-03-21T15:50:35Z

On Mon, Mar 10, 2014 at 7:29 AM, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:
> On Mon, Mar 10, 2014 at 11:58:08AM +0100, Maxime Ripard wrote:
>> On Fri, Mar 07, 2014 at 04:08:36PM +0000, Russell King - ARM Linux wrote:
>> > On Fri, Mar 07, 2014 at 03:59:30PM +0100, Maxime Ripard wrote:
>> > > @@ -900,7 +902,8 @@ mv64xxx_i2c_probe(struct platform_device *pd)
>> > > exit_free_irq:
>> > > free_irq(drv_data->irq, drv_data);
>> > > exit_reset:
>> > > - if (pd->dev.of_node && !IS_ERR(drv_data->rstc))
>> > > + if (pd->dev.of_node && IS_ENABLED(CONFIG_RESET_CONTROLLER) &&
>> > > + !IS_ERR(drv_data->rstc))
>> > > reset_control_assert(drv_data->rstc);
>> >
>> > Another question is... why do we need to check pd->dev.of_node here?
>> > If CONFIG_RESET_CONTROLLER is set, we always try to get the reset
>> > controller node, so drv_data->rstc is either going to be a valid
>> > pointer, or it's going to be an error pointer - neither
>> > reset_control_get() nor devm_reset_control_get return NULL.
>>
>> Following back on this as I was doing the patch, actually,
>> drv_data->rstc will be NULL if we're not probed by DT, and hence never
>> call reset_control_get, that would set an error pointer.
>>
>> But then, we can use IS_ERR_OR_NULL on drv_data->rstc.
>
> I think you can also move the devm_reset_control_get() into the main
> probe function: you're only checking for -EPROBE_DEFER from it to fail,
> allowing other errors to continue with the driver init. This means
> that on non-OF, devm_reset_control_get() will fail with -ENOENT.

Looping linux-next into the CC since this is the cause of the failure
in orion5x_defconfig there, and no point in anyone else re-doing the
same bisect.

Paul.
--

Bisecting: 0 revisions left to test after this (roughly 0 steps)
[80c69915e5fbe6493119d87eee2a2a6a7115c74c] i2c: mv64xxx: fix circular
Kconfig dependency
running ./x
#
# configuration written to .config
#
drivers/built-in.o: In function `mv64xxx_i2c_remove':
/home/paul/git/linux-head/drivers/i2c/busses/i2c-mv64xxx.c:924:
undefined reference to `reset_control_assert'
drivers/built-in.o: In function `mv64xxx_i2c_probe':
/home/paul/git/linux-head/drivers/i2c/busses/i2c-mv64xxx.c:904:
undefined reference to `reset_control_assert'
drivers/built-in.o: In function `mv64xxx_of_config':
/home/paul/git/linux-head/drivers/i2c/busses/i2c-mv64xxx.c:771:
undefined reference to `devm_reset_control_get'
/home/paul/git/linux-head/drivers/i2c/busses/i2c-mv64xxx.c:778:
undefined reference to `reset_control_deassert'
make: *** [vmlinux] Error 1
80c69915e5fbe6493119d87eee2a2a6a7115c74c is the first bad commit
commit 80c69915e5fbe6493119d87eee2a2a6a7115c74c
Author: Wolfram Sang <wsa@the-dreams.de>
Date: Thu Mar 6 10:08:50 2014 +0100

i2c: mv64xxx: fix circular Kconfig dependency

Commit 370136bc67c3 ("i2c: mv64xxx: Add reset deassert call")
introduced:

drivers/video/Kconfig:42:error: recursive dependency detected!

ARCH_SUNXI selects RESET_CONTROLLER anyhow.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

:040000 040000 533a0ca6b40f2dd1d0b3bb434e6ed13ff4796953
cfd47b9ad19651148a2d0d4fa3a4df0b8cbbe1df M drivers
bisect run success

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