Commit graph

18 commits

Author SHA1 Message Date
Guennadi Liakhovetski 162f43e31c mmc: tmio: fix a deadlock
Currently the tmio-mmc driver contains a recursive runtime PM method
invocation, which leads to a deadlock on a mutex. Avoid it by taking
care not to request DMA too early.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-07-21 10:35:07 -04:00
Guennadi Liakhovetski 71d111cd34 mmc: tmio: maximize power saving
This patch uses runtime PM to allow the system to power down the MMC
controller, when the MMC closk is switched off.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-07-21 10:35:06 -04:00
Guennadi Liakhovetski b9269fdd4f mmc: tmio: fix recursive spinlock, don't schedule with interrupts disabled
Calling mmc_request_done() under a spinlock with interrupts disabled
leads to a recursive spin-lock on request retry path and to
scheduling in atomic context. This patch fixes both these problems
by moving mmc_request_done() to the scheduler workqueue.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-07-21 10:35:05 -04:00
Paul Parsons e312eb1e66 mmc: tmio: Fix race condition resulting in spurious interrupts
There is a race condition in the tmio_mmc_irq() interrupt handler,
caused by the presence of a while loop, which results in warnings of
spurious interrupts. This was found on an HP iPAQ hx4700 whose HTC
ASIC3 reportedly incorporates the Toshiba TC6380AF controller.

Towards the end of a multiple read (CMD18) operation the handler clears
the final RXRDY status bit in the first loop iteration, sees the DATAEND
status bit at the bottom of the loop, and so clears the DATAEND status
bit in the second loop iteration. However the DATAEND interrupt is still
queued in the system somewhere and can't be delivered until the handler
has returned. This second interrupt is then reported as spurious in the
next call to the handler. Likewise for single read (CMD17) operations.
And something similar occurs for multiple write (CMD25) and single write
(CMD24) operations, where CMDRESPEND and TXRQ status bits are cleared in
a single call.

In these cases the interrupt handler clears two separate interrupts when
it should only clear the one interrupt for which it was invoked. The fix
is to remove the while loop.

Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-07-20 17:21:01 -04:00
Simon Horman a11862d338 mmc: tmio: Share register access functions
Move register access functions into a shared header.
Use sd_ctrl_write16 in tmio_mmc_dma.c:tmio_mmc_enable_dma().

Other than avoiding (trivial) open-coding, the motivation for
this is to allow platform-hooks in access functions to
be applied across all applicable accesses.

Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Magnus Damm <magnus.damm@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-07-20 17:20:56 -04:00
Guennadi Liakhovetski 7d8b4c2a4b mmc: tmio: fix regression in TMIO_MMC_WRPROTECT_DISABLE handling
Commit b6147490e6 ("mmc: tmio: split core functionality, DMA and
MFD glue") broke handling of the TMIO_MMC_WRPROTECT_DISABLE flag by
the tmio-mmc driver. This patch restores the original behaviour.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-06-25 18:52:15 -04:00
Guennadi Liakhovetski 7311bef069 mmc: tmio: runtime suspend the controller, where possible
The TMIO MMC controller cannot be powered off to save power, when no
card is plugged in, because then it will not be able to detect a new
card-insertion event. On some implementations, however, it is
possible to switch to using another source to detect card insertion.
This patch adds support for such implementations.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-05-24 23:53:55 -04:00
Magnus Damm 8e7bfdb37a mmc: tmio/sdhi: break out interrupt request/free
Move request_irq()/free_irq() from the shared code
in tmio_mmc.c into the SDHI/tmio specific portion
in sh_mobile_sdhi.c and tmio_mmc_pio.c.

This is ground work to allow us to adjust the SDHI
code with IRQ flags and number of interupt sources.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-05-24 23:53:52 -04:00
Guennadi Liakhovetski df3ef2d3c9 mmc: protect the tmio_mmc driver against a theoretical race
The MMC subsystem does not guarantee, that host driver .request() and
.set_ios() callbacks are serialised. Such concurrent calls, however,
do not have to be meaningfully supported, drivers just have to make
sure to avoid any severe problems.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-05-24 23:53:52 -04:00
Guennadi Liakhovetski e6ee7182c3 mmc: Add runtime and system-wide PM to the TMIO MMC driver
Add runtime and system-wide power management to the TMIO MMC driver
in PIO and DMA modes, allowing it to properly save and restore its
state during system suspend. Runtime PM is very crude ATM, because
the controller has to be powered on all the time to detect card
hotplug events.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-05-24 23:53:51 -04:00
Guennadi Liakhovetski c919c2a073 mmc: tmio: fix .set_ios(MMC_POWER_UP) handling
The aggressive clock gating for TMIO MMC patch has broken switching
interface power on, using MFD or platform callbacks. Restore the
ios->power_mode == MMC_POWER_UP && ios->clock == 0 case handling.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-04-27 19:16:29 -04:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Simon Horman cba179aec7 mmc: tmio_mmc: Move some defines into a shared header
Also add TMIO_BBS.

This allows these defines to also be used by zboot.

Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-26 15:58:50 -04:00
Guennadi Liakhovetski 5fd0157901 mmc: tmio: support aggressive clock gating
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-25 10:39:59 -04:00
Guennadi Liakhovetski a7edbe399b mmc: tmio: fix power-mode interpretation
The power-mode sequence on MMC is MMC_POWER_OFF -> MMC_POWER_UP ->
MMC_POWER_ON and not MMC_POWER_ON -> MMC_POWER_UP, as the driver currently
is implying.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-25 10:39:58 -04:00
Guennadi Liakhovetski d9b0342177 mmc: tmio: remove work-around for unmasked SDIO interrupts
SDIO IRQs got unmasked on sh-mobile while writing to the
CTL_CLK_AND_WAIT_CTL register, because that register at address 0x138
is not implemented on those SoCs and writes to it overwrite the
register at address 0x38: CTL_SDIO_IRQ_MASK. Previous patches
eliminated access to register above 0xff on sh-mobile, so that this
work-around isn't needed anymore.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-25 10:39:56 -04:00
Guennadi Liakhovetski 69d1fe18e9 mmc: tmio: only access registers above 0xff, if available
Not all tmio implementations have registers above oxff. Accessing
them on thise platforms is dangerous. In some cases it leads to
address wrapping to addresses below 0x100, which corrupts random
unrelated registers.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-25 10:39:49 -04:00
Guennadi Liakhovetski b6147490e6 mmc: tmio: split core functionality, DMA and MFD glue
TMIO MMC chips contain an SD / SDIO IP core from Panasonic, similar to
the one, used in MN5774 and other MN57xx controllers. These IP cores are
included in many multifunction devices, in sh-mobile chips from Renesas,
in the latter case they can also use DMA. Some sh-mobile implementations
also have some other specialities, that MFD-based solutions don't have.
This makes supporting all these features in a monolithic driver inconveniet
and error-prone. This patch splits the driver into 3 parts: the core,
the MFD glue and the DMA support. In case of a modular build, two modules
will be built: mmc_tmio_core and mmc_tmio.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-03-25 10:39:11 -04:00