Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader on
 Intel NUC boxes
From:   Chris Clayton <chris2553@googlemail.com>
To:     LKML <linux-kernel@vger.kernel.org>, ricky_wu@realtek.com,
        gregkh@linuxfoundation.org, rdunlap@infradead.org,
        philquadra@gmail.com, Arnd Bergmann <arnd@arndb.de>
References: <862172f0-cd23-800c-27b1-27cb49e99099@googlemail.com>
Message-ID: <a9a94d7f-4873-7a10-4911-f3c760257c5c@googlemail.com>
Date:   Sun, 2 Aug 2020 20:58:33 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.1.0
MIME-Version: 1.0
In-Reply-To: <862172f0-cd23-800c-27b1-27cb49e99099@googlemail.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-GB
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Sorry, I should have said that the patch is against 5.7.12. It applies to upstream, but with offsets.

On 02/08/2020 20:48, Chris Clayton wrote:
> bede03a579b3 introduced a bug which leaves the rts5229 PCI Express card reader on my Intel NUC6CAYH box.
> 
> The bug is in drivers/misc/cardreader/rtsx_pcr.c. A call to rtsx_pci_init_ocp() was added to rtsx_pci_init_hw().
> At the call point, pcr->ops->init_ocp is NULL and pcr->option.ocp_en is 0, so in rtsx_pci_init_ocp() the cardreader
> gets disabled.
> 
> I've avoided this by making excution code that results in the reader being disabled conditional on the device
> not being an RTS5229. Of course, other rtsxxx card readers may also be disabled by this bug. I don't have the
> knowledge to address that, so I'll leave to the driver maintainers.
> 
> The patch to avoid the bug is attached.
> 
> Fixes: bede03a579b3 ("misc: rtsx: Enable OCP for rts522a rts524a rts525a rts5260")
> Link: https://marc.info/?l=linux-kernel&m=159105912832257
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=204003
> Signed-off-by: Chris Clayton <chris2553@googlemail.com>
> 
> bede03a579b3 introduced a bug which leaves the rts5229 PCI Express card reader on my Intel NUC6CAYH box.
> 
> The bug is in drivers/misc/cardreader/rtsx_pcr.c. A call to rtsx_pci_init_ocp() was added to rtsx_pci_init_hw().
> At the call point, pcr->ops->init_ocp is NULL and pcr->option.ocp_en is 0, so in rtsx_pci_init_ocp() the cardreader
> gets disabled.
> 
> I've avoided this by making excution code that results in the reader being disabled conditional on the device
> not being an RTS5229. Of course, other rtsxxx card readers may also be disabled by this bug. I don't have the
> knowledge to address that, so I'll leave to the driver maintainers.
> 
> The patch to avoid the bug is attached.
> 
> Chris
>