linux-uconsole/drivers/mmc/core
Daniel Drake 3ed000cd76 mmc: avoid removing non-removable hosts during suspend
[ Upstream commit de8dcc3d2c ]

The Weibu F3C MiniPC has an onboard AP6255 module, presenting
two SDIO functions on a single MMC host (Bluetooth/btsdio and
WiFi/brcmfmac), and the mmc layer correctly detects this as
non-removable.

After suspend/resume, the wifi and bluetooth interfaces disappear
and do not get probed again.

The conditions here are:

 1. During suspend, we reach mmc_pm_notify()

 2. mmc_pm_notify() calls mmc_sdio_pre_suspend() to see if we can
    suspend the SDIO host. However, mmc_sdio_pre_suspend() returns
    -ENOSYS because btsdio_driver does not have a suspend method.

 3. mmc_pm_notify() proceeds to remove the card

 4. Upon resume, mmc_rescan() does nothing with this host, because of
    the rescan_entered check which aims to only scan a non-removable
    device a single time (i.e. during boot).

Fix the loss of functionality by detecting that we are unable to
suspend a non-removable host, so avoid the forced removal in that
case. The comment above this function already indicates that this
code was only intended for removable devices.

Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 10:58:47 +01:00
..
bus.c mmc: core: Do not leave the block driver in a suspended state 2017-12-05 11:22:51 +01:00
bus.h
core.c mmc: avoid removing non-removable hosts during suspend 2018-03-24 10:58:47 +01:00
core.h mmc: core: Remove MMC_CLKGATE 2015-10-26 16:00:09 +01:00
debugfs.c mmc: core: Remove MMC_CLKGATE 2015-10-26 16:00:09 +01:00
host.c mmc: core: Add DT bindings for eMMC hardware reset support 2015-10-27 10:21:15 +01:00
host.h mmc: host: Add facility to support re-tuning 2015-06-01 09:06:53 +02:00
Kconfig mmc: core: Remove MMC_CLKGATE 2015-10-26 16:00:09 +01:00
Makefile mmc: pwrseq: add driver for emmc hardware reset 2015-02-04 09:45:09 +01:00
mmc.c mmc: core: fix multi-bit bus width without high-speed mode 2017-02-23 17:43:10 +01:00
mmc_ops.c mmc: mmc: extend the mmc_send_tuning() 2015-10-27 10:38:41 +01:00
mmc_ops.h mmc: core: Convert __mmc_switch() into an internal core function 2015-10-26 15:59:54 +01:00
pwrseq.c mmc: pwrseq: Fix error code propagation in mmc_pwrseq_simple_alloc() 2015-04-17 10:17:19 +02:00
pwrseq.h mmc: pwrseq: simplify alloc/free hooks 2015-03-23 14:13:42 +01:00
pwrseq_emmc.c mmc: pwrseq: Use highest priority for eMMC restart handler 2015-10-27 11:11:06 +01:00
pwrseq_simple.c mmc: pwrseq_simple: use GPIO descriptors array API 2015-10-26 15:59:59 +01:00
quirks.c mmc: core: Remove MMC_CLKGATE 2015-10-26 16:00:09 +01:00
sd.c mmc: core: Enable tuning according to the actual timing 2016-03-03 15:07:15 -08:00
sd.h mmc: drop the speed mode of card's state 2014-05-12 18:05:53 -04:00
sd_ops.c mmc: sd: warn if card stays busy during init 2014-07-09 11:26:07 +02:00
sd_ops.h
sdio.c mmc: core: Enable tuning according to the actual timing 2016-03-03 15:07:15 -08:00
sdio_bus.c mmc: sdio: fix alignment issue in struct sdio_func 2017-10-08 10:14:19 +02:00
sdio_bus.h
sdio_cis.c
sdio_cis.h
sdio_io.c
sdio_irq.c mmc: core: Remove MMC_CLKGATE 2015-10-26 16:00:09 +01:00
sdio_ops.c
sdio_ops.h mmc: Add mmc_is_io_op helper function 2015-10-26 16:00:01 +01:00
slot-gpio.c mmc: slot-gpio: Allow host driver to provide isr for card-detect interrupts 2015-01-19 09:56:29 +01:00
slot-gpio.h mmc: slot-gpio: Make mmc_gpio_alloc() available for MMC core 2015-01-19 09:56:17 +01:00