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From: Ulf Hansson <ulf.hansson@linaro.org>
To: linux-mmc@vger.kernel.org, Ulf Hansson <ulf.hansson@linaro.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	Douglas Anderson <dianders@chromium.org>,
	Matthias Kaehlcke <mka@chromium.org>
Cc: Kalle Valo <kvalo@codeaurora.org>,
	Tony Lindgren <tony@atomide.com>, Wen Gong <wgong@codeaurora.org>,
	Erik Stromdahl <erik.stromdahl@gmail.com>,
	Eyal Reizer <eyalreizer@gmail.com>,
	linux-wireless@vger.kernel.org
Subject: [PATCH 0/2] mmc: core: Fixup HW reset for SDIO cards
Date: Thu, 17 Oct 2019 15:57:37 +0200	[thread overview]
Message-ID: <20191017135739.1315-1-ulf.hansson@linaro.org> (raw)

It has turned out that it's not a good idea to try to power cycle and to
re-initialize the SDIO card, as currently done through mmc_hw_reset(). This
because there may be multiple SDIO funcs attached to the same SDIO card and
some of the others that didn't execute the call to mmc_hw_reset(), may then
simply experience an undefined behaviour.

The following two patches in this series attempts to address this problem, by
reworking the mmc_hw_reset() behaviour for SDIO.

Note that, the code has only compile tested, so any test on HW is greatly
appreciated.

Kind regards
Uffe


Ulf Hansson (2):
  mmc: core: Drop check for mmc_card_is_removable() in mmc_rescan()
  mmc: core: Re-work HW reset for SDIO cards

 drivers/mmc/core/core.c | 10 +++-------
 drivers/mmc/core/core.h |  2 ++
 drivers/mmc/core/sdio.c | 11 +++++++++--
 3 files changed, 14 insertions(+), 9 deletions(-)

-- 
2.17.1


WARNING: multiple messages have this Message-ID (diff)
From: Ulf Hansson <ulf.hansson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
To: linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Ulf Hansson <ulf.hansson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
	Adrian Hunter
	<adrian.hunter-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
	Douglas Anderson
	<dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>,
	Matthias Kaehlcke <mka-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Cc: Kalle Valo <kvalo-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>,
	Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>,
	Wen Gong <wgong-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>,
	Erik Stromdahl
	<erik.stromdahl-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	Eyal Reizer <eyalreizer-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: [PATCH 0/2] mmc: core: Fixup HW reset for SDIO cards
Date: Thu, 17 Oct 2019 15:57:37 +0200	[thread overview]
Message-ID: <20191017135739.1315-1-ulf.hansson@linaro.org> (raw)

It has turned out that it's not a good idea to try to power cycle and to
re-initialize the SDIO card, as currently done through mmc_hw_reset(). This
because there may be multiple SDIO funcs attached to the same SDIO card and
some of the others that didn't execute the call to mmc_hw_reset(), may then
simply experience an undefined behaviour.

The following two patches in this series attempts to address this problem, by
reworking the mmc_hw_reset() behaviour for SDIO.

Note that, the code has only compile tested, so any test on HW is greatly
appreciated.

Kind regards
Uffe


Ulf Hansson (2):
  mmc: core: Drop check for mmc_card_is_removable() in mmc_rescan()
  mmc: core: Re-work HW reset for SDIO cards

 drivers/mmc/core/core.c | 10 +++-------
 drivers/mmc/core/core.h |  2 ++
 drivers/mmc/core/sdio.c | 11 +++++++++--
 3 files changed, 14 insertions(+), 9 deletions(-)

-- 
2.17.1

             reply	other threads:[~2019-10-17 13:57 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-17 13:57 Ulf Hansson [this message]
2019-10-17 13:57 ` [PATCH 0/2] mmc: core: Fixup HW reset for SDIO cards Ulf Hansson
2019-10-17 13:57 ` [PATCH 1/2] mmc: core: Drop check for mmc_card_is_removable() in mmc_rescan() Ulf Hansson
2019-10-17 13:57   ` Ulf Hansson
2019-10-21 22:13   ` Doug Anderson
2019-10-21 22:13     ` Doug Anderson
2019-10-22  6:19     ` Ulf Hansson
2019-10-22  6:19       ` Ulf Hansson
2019-10-17 13:57 ` [PATCH 2/2] mmc: core: Re-work HW reset for SDIO cards Ulf Hansson
2019-10-17 13:57   ` Ulf Hansson
2019-10-21 22:13   ` Doug Anderson
2019-10-21 22:13     ` Doug Anderson
2019-10-22  6:51     ` Ulf Hansson
2019-10-22  6:51       ` Ulf Hansson
2019-10-22 14:47       ` Doug Anderson
2019-10-22 14:47         ` Doug Anderson
2019-10-23 15:06         ` Ulf Hansson
2019-10-23 15:06           ` Ulf Hansson
2019-10-25 14:16           ` Ulf Hansson
2019-10-25 14:16             ` Ulf Hansson

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