devm_ioremap_resource() has recorded error log, so it's
unnecessary to record log again.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20210409015424.3277212-1-jiayang5@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
devm_ioremap_resource() has recorded error log, so it's
unnecessary to record log again.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Laibin Qiu <qiulaibin@huawei.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/20210409023349.3325907-1-qiulaibin@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Now that we got the timeout handling in the driver correct, we can use
this capability to avoid polling via the MMC core.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210409094606.4317-1-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
CMD8 is not supported with Command Queue Enabled. Add required callback
to clear CQE_EN and CQE_INTR fields in the host controller register
before sending CMD8. Add corresponding callback in the CQHCI resume path
to re-enable CQE_EN and CQE_INTR fields.
Reported-by: Kamal Mostafa <kamal@canonical.com>
Tested-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Aniruddha Tvs Rao <anrao@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20210407094617.770495-1-jonathanh@nvidia.com
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
For GL9763E, although there is the best performance at the maximum delay.
Change the value to 20us in order to have better power consumption.
This change may reduce the maximum performance by 10%.
Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Link: https://lore.kernel.org/r/20210407093816.8863-1-benchuanggli@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Fixes the following W=1 kernel build warning(s):
drivers/mmc/host/moxart-mmc.c:257:7: warning: variable ‘dma_time’ set
but not used
drivers/mmc/host/moxart-mmc.c:395:7: warning: variable ‘pio_time’ set
but not used
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/1617357231-93064-1-git-send-email-yang.lee@linux.alibaba.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As the density increases, the 4-minute timeout value for sanitize is no
longer feasible. At the same time, devices of different densities have
different timeout values, which makes it difficult to use a common timeout
value. Therefore, let's pass down the userland-specified sanitize timeout
value so it can be used.
Signed-off-by: Bean Huo <beanhuo@micron.com>
Link: https://lore.kernel.org/r/20210402092432.25069-2-huobean@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Bus power may control card power, but the full reset done by SDHCI at
initialization still may not reset the power, whereas a direct write to
SDHCI_POWER_CONTROL can. That might be needed to initialize correctly, if
the card was left powered on previously.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210331081752.23621-1-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As indicated by function esdhc_change_pinstate(), SDR50 and DDR50
require pins_100mhz, while SDR104 and HS400 require pins_200mhz. Some
system design may support SDR50 and DDR50 with 100mhz pin state only
(without 200mhz one). Currently the combined 100/200 MHz pinctrl state
check prevents such system from running SDR50 and DDR50. Separate the
check to support such system design.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Haibo Chen <haibo.chen@nxp.com>
Link: https://lore.kernel.org/r/20210326110214.28416-1-shawnguo@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Remove the CQHCI_QUIRK_SHORT_TXFR_DESC_SZ quirk because the
latest chips have this fixed and earlier chips have other
CQE problems that prevent the feature from being enabled.
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210325192834.42955-1-alcooperx@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As pointed out by Ulf, "both "mmc->parent" and mmc_dev(mmc) are being
used in the entire c-file". Convert all the mmc->parent usage in all
sdhci host driver to mmc_dev() for consistency.
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Link: https://lore.kernel.org/r/20210324155013.1e5faa3c@xhacker.debian
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Fix to return negative error code -ENOMEM from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: c2c4da37837e ("mmc: sdhci-of-dwcmshc: add rockchip platform support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20210323112956.1016884-1-weiyongjun1@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit adds ACPI support in the sdhci-of-dwcmshc driver for
BlueField-3 SoC. It has changes to only use the clock hierarchy
for Deviec Tree since the clk is not supported by ACPI. Instead,
ACPI can define 'clock-frequency' which is parsed by existing
sdhci_get_property(). This clock value will be returned in function
dwcmshc_get_max_clock().
Signed-off-by: Liming Sun <limings@nvidia.com>
Reviewed-by: Khalil Blaiech <kblaiech@nvidia.com>
Link: https://lore.kernel.org/r/1616453211-275165-1-git-send-email-limings@nvidia.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
After reset, we manually flagged retune in runtime resume, but missed it
in the workqueue. To fix that and avoid the problem in the future, let's
flag retune in the reset handler directly whenever a card is present.
Reported-by: Takeshi Saito <takeshi.saito.xv@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210316085717.7276-3-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Resetting the IP core will lose the bus width information and not all
code paths recover it. So, make sure the latest bus width gets restored
in the reset routine. For that, tmio_mmc_set_bus_width() is moved, but
not modified.
Signed-off-by: Takeshi Saito <takeshi.saito.xv@renesas.com>
[wsa: reworded commit message]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210316085717.7276-2-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This variant is present on a Lenovo IdeaPad Slim 1, which uses an AMD Dali/Athlon Silver 3050e.
The Windows AMD SD Host Controller driver also lists this as a valid device ID.
Adding this device ID makes the internal eMMC storage on the Lenovo accessible.
Consequently this makes Linux installable and usable on it as well.
Signed-off-by: James Young <james@pocketfluff.org>
Link: https://lore.kernel.org/r/20210318124025.3002861-1-james@pocketfluff.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
All recent SDHI instances can be reset via the reset controller. If one
is found, use it instead of the open coded reset. This is to get a
future-proof sane reset state.
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210317091622.31890-4-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
renesas_sdhi_reset used to mainly reset the SCC but is now doing more
and even more will be added. So, factor out SCC reset to have a clear
distinction when we want to reset either SCC or SDHI+SCC.
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210317091622.31890-3-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
We will soon allow resetting the whole IP core via a reset controller.
For this case, DMA must be terminated before the actual reset. For the
other cases, it is probably better, too.
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210317091622.31890-2-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The retrieval of driver data can be a bit simplified by using
device_get_match_data(), so switch to it.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20210314230824.148969-2-festevam@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
i.MX has been converted to a devicetree only platform, so remove
the non-DT stub for sdhci_esdhc_imx_probe_dt().
Also, make the driver depend on OF now.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20210314230824.148969-1-festevam@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The mmc core uses a PM notifier to temporarily during system suspend, turn
off the card detection mechanism for removal/insertion of (e)MMC/SD/SDIO
cards. Additionally, the notifier may be used to remove an SDIO card
entirely, if a corresponding SDIO functional driver don't have the system
suspend/resume callbacks assigned. This behaviour has been around for a
very long time.
However, a recent bug report tells us there are problems with this
approach. More precisely, when receiving the PM_SUSPEND_PREPARE
notification, we may end up hanging on I/O to be completed, thus also
preventing the system from getting suspended.
In the end what happens, is that the cancel_delayed_work_sync() in
mmc_pm_notify() ends up waiting for mmc_rescan() to complete - and since
mmc_rescan() wants to claim the host, it needs to wait for the I/O to be
completed first.
Typically, this problem is triggered in Android, if there is ongoing I/O
while the user decides to suspend, resume and then suspend the system
again. This due to that after the resume, an mmc_rescan() work gets punted
to the workqueue, which job is to verify that the card remains inserted
after the system has resumed.
To fix this problem, userspace needs to become frozen to suspend the I/O,
prior to turning off the card detection mechanism. Therefore, let's drop
the PM notifiers for mmc subsystem altogether and rely on the card
detection to be turned off/on as a part of the system_freezable_wq, that we
are already using.
Moreover, to allow and SDIO card to be removed during system suspend, let's
manage this from a ->prepare() callback, assigned at the mmc_host_class
level. In this way, we can use the parent device (the mmc_host_class
device), to remove the card device that is the child, in the
device_prepare() phase.
Reported-by: Kiwoong Kim <kwmad.kim@samsung.com>
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210310152900.149380-1-ulf.hansson@linaro.org
Reviewed-by: Kiwoong Kim <kwmad.kim@samsung.com>
Fix the following coccicheck warning:
./drivers/mmc/host/via-sdmmc.c:1274:5-8: Unneeded variable: "ret".
Return "0" on line 1295
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/1615272478-52458-1-git-send-email-yang.lee@linux.alibaba.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As of commit bb475230b8 ("reset: make optional functions really
optional"), the reset framework API calls use NULL pointers to describe
optional, non-present reset controls.
This allows to return errors from devm_reset_control_get_optional and to
call reset_control_(de)assert unconditionally.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20210305090724.18832-1-p.zabel@pengutronix.de
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As of commit bb475230b8 ("reset: make optional functions really
optional"), the reset framework API calls use NULL pointers to describe
optional, non-present reset controls.
This allows to return errors from devm_reset_control_get_optional and to
call reset_control_(de)assert unconditionally.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20210305090827.19124-1-p.zabel@pengutronix.de
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The host->cqe_enabled is already containing the needed information about
whether the CQE is enabled or not, hence there is no need to keep another
copy of it around.
Signed-off-by: Luca Porzio <lporzio@micron.com>
Signed-off-by: Zhan Liu <zliua@micron.com>
Link: https://lore.kernel.org/r/20210215003217.GA12240@lupo-laptop
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Returning zero to indicate success, when we actually have failed to probe
is wrong. As a matter of fact, it leads to that mmc_blk_remove() gets
called at a card removal and then triggers "NULL pointer dereference"
splats. This is because mmc_blk_remove() relies on data structures and
pointers to be setup from mmc_blk_probe(), of course.
There have been no errors reported about this, which is most likely because
mmc_blk_probe() never fails like this. Nevertheless, let's fix the code by
propagating the error codes correctly and prevent us from leaking memory by
calling also destroy_workqueue() in the error path.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-4-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
To simplify the code, move the logging into the common mmc_blk_alloc_req()
and drop the rather useless information about the partition type/id.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-3-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
mmc_blk_probe() isn't a hotpath, which makes it's questionable to use
unlikely(). Therefore let's simply drop it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210303122049.151986-2-ulf.hansson@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Populate the new member for custom mask values to make sure this value
is applied whenever needed. Also, rename the define holding the value
because this is not only about initialization anymore.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210304092903.8534-1-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
For data read commands, SDHC may initiate data transfers even before it
completely process the command response. In case command itself fails,
driver un-maps the memory associated with data transfer but this memory
can still be accessed by SDHC for the already initiated data transfer.
This scenario can lead to un-mapped memory access error.
To avoid this scenario, reset SDHC (when command fails) prior to
un-mapping memory. Resetting SDHC ensures that all in-flight data
transfers are either aborted or completed. So we don't run into this
scenario.
Swap the reset, un-map steps sequence in sdhci_request_done().
Suggested-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
Signed-off-by: Pradeep P V K <pragalla@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/1614760331-43499-1-git-send-email-pragalla@qti.qualcomm.com
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
It's odd to adopt different error handling on failure of
pci_read_config_dword(). Check the return value and terminate
execution flow on failure of all pci_read_config_dword() calls
in this function.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20210226084146.29095-1-dinghao.liu@zju.edu.cn
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Short circuit protection mechanism of GL9755 is disabled by HW default
setting. Enable short circuit protection to prevent GL9755 from being
damaged by short circuit or over current.
Signed-off-by: Renius Chen <reniuschengl@gmail.com>
Link: https://lore.kernel.org/r/20210225111307.62975-1-reniuschengl@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
When imx_data->pinctrl is not a valid pointer, pinctrl_lookup_state
will trigger kernel panic.
When we boot Dual OS on Jailhouse hypervisor, we let the 1st Linux to
configure pinmux ready for the 2nd OS, so the 2nd OS not have pinctrl
settings.
Similar to this commit b62eee9f80 ("mmc: sdhci-esdhc-imx: no fail when no pinctrl available").
Reviewed-by: Bough Chen <haobo.chen@nxp.com>
Reviewed-by: Alice Guo <alice.guo@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/1614222604-27066-6-git-send-email-peng.fan@oss.nxp.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
SDHI Gen2+ has a different value for TMIO_MASK_ALL, so add a member to
support that. If the member is not used, the previous default value is
applied.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210223100830.25125-2-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Some of SD cards sets permanent write protection bit in their CSD register,
due to lifespan or internal problem. To avoid unnecessary I/O write
operations, let's parse the bits in the CSD during initialization and mark
the card as read only for this case.
Signed-off-by: Seunghui Lee <sh043.lee@samsung.com>
Link: https://lore.kernel.org/r/20210222083156.19158-1-sh043.lee@samsung.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
A 'tmio_mmc_host_free()' call is missing in the remove function, in order
to balance a 'tmio_mmc_host_alloc()' call in the probe.
This is done in the error handling path of the probe, but not in the remove
function.
Add the missing call.
Fixes: 3fd784f745 ("mmc: uniphier-sd: add UniPhier SD/eMMC controller driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210220142953.918608-1-christophe.jaillet@wanadoo.fr
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
A 'uniphier_sd_clk_enable()' call should be balanced by a corresponding
'uniphier_sd_clk_disable()' call.
This is done in the remove function, but not in the error handling path of
the probe.
Add the missing call.
Fixes: 3fd784f745 ("mmc: uniphier-sd: add UniPhier SD/eMMC controller driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210220142935.918554-1-christophe.jaillet@wanadoo.fr
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
RPM handling has been improved twice since this comment, and also SCC
handling has been improved a lot. All the testing we did (Geert's and
Niklas' and Wolfram's board farms) with the workaround removed did not
lead to problems, so it is time to get rid of it to the best of our
knowledge.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20210218110224.6910-1-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
mmc_spi_send_{csd|cid} have similar function body. Let's remove the
duplicated part to simplify the code, just add opcode to distinguish
them in changed mmc_spi_send_cxd().
Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20210215015116.1355-1-zbestahu@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The ->card_event callback isn't being used by any of the dw_mmc variants.
It's likely a leftover from an earlier change, hence let's just drop the
redundant call to it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
When the mmc_rescan work is enabled for execution (host->rescan_disable),
it's the only instance per mmc host that is allowed to set/clear the
host->bus_ops pointer.
Besides the mmc_rescan work, there are a couple of scenarios when the
host->bus_ops pointer may be accessed. Typically, those can be described as
as below:
*)
Upper mmc driver layers (like the mmc block device driver or an SDIO
functional driver) needs to execute a host->bus_ops callback. This can be
considered as safe without having to use some special locking mechanism,
because they operate on top of the struct mmc_card. As long as there is a
card to operate upon, the mmc core guarantees that there is a host->bus_ops
assigned as well. Note that, upper layer mmc drivers are of course
responsible to clean up from themselves from their ->remove() callbacks,
otherwise things would fall apart anyways.
**)
Via the mmc host instance, we may need to force a removal of an inserted
mmc card. This happens when a mmc host driver gets unbind, for example. In
this case, we protect the host->bus_ops pointer from concurrent accesses,
by disabling the mmc_rescan work upfront (host->rescan_disable). See
mmc_stop_host() for example.
This said, it seems like the reference counting of the host->bus_ops
pointer at some point have become superfluous. As this is an old mechanism
of the mmc core, it a bit difficult to digest the history of when that
could have happened. However, let's drop the reference counting to avoid
unnecessary code-paths and lockings.
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210212131610.236843-1-ulf.hansson@linaro.org
The mmc_hw|sw_reset() APIs are designed to be called solely from upper
layers, which means drivers that operates on top of the struct mmc_card,
like the mmc block device driver and an SDIO functional driver.
Additionally, as long as the struct mmc_host has a valid pointer to a
struct mmc_card, the corresponding host->bus_ops pointer stays valid and
assigned.
For these reasons, let's drop the superfluous reference counting and the
redundant validations in mmc_hw|sw_reset().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210212131532.236775-1-ulf.hansson@linaro.org
