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Subject: Re: [PATCH v1] spi: xtensa-xtfpga: Fix a double put() in
 xtfpga_spi_remove()
To:     Mark Brown <broonie@kernel.org>, Max Filippov <jcmvbkbc@gmail.com>
CC:     Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        <linux-kernel@vger.kernel.org>, <kernel-janitors@vger.kernel.org>,
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 <Y5dKk+uw3UcW2Pu1@sirena.org.uk>
From:   Yang Yingliang <yangyingliang@huawei.com>
Message-ID: <bdb26ba3-7276-359a-7784-6ec3e35c64de@huawei.com>
Date:   Tue, 13 Dec 2022 09:30:32 +0800
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On 2022/12/12 23:36, Mark Brown wrote:
> On Sat, Dec 10, 2022 at 06:48:02AM -0800, Max Filippov wrote:
>> Hi Christophe,
>>
>> On Sat, Dec 10, 2022 at 3:52 AM Christophe JAILLET
>> <christophe.jaillet@wanadoo.fr> wrote:
>>> 'master' is allocated with devm_spi_alloc_master(), there is no need to
>>> put it explicitly in the remove function.
>>>          spi_bitbang_stop(&xspi->bitbang);
>>> -       spi_master_put(master);
>> This put is matching the get in the spi_bitbang_start.
>> It was discussed here:
>> https://lore.kernel.org/linux-spi/CAMo8BfJaD7pG_iutY8jordysjChyzhTpVSqpxXh3QoZsj2QmaQ@mail.gmail.com/
> Probably worth a comment though since it is a bit of a gotcha.  Ideally
> we'd improve this in the bitbang code but that's harder.
Ideally, spi_bitbang_stop() should undo spi_bitbang_start(). shall we 
move spi_master_put() in spi_bitbang_stop() instead of
calling it separately in drivers?

Thanks,
Yang