The card is not necessarily being removed, but the debugfs files must be
removed when the driver is removed, otherwise they will continue to exist
after unbinding the card from the driver. e.g.
# echo "mmc1:0001" > /sys/bus/mmc/drivers/mmcblk/unbind
# cat /sys/kernel/debug/mmc1/mmc1\:0001/ext_csd
[ 173.634584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
[ 173.643356] IP: mmc_ext_csd_open+0x5e/0x170
A complication is that the debugfs_root may have already been removed, so
check for that too.
Fixes: 627c3ccfb4 ("mmc: debugfs: Move block debugfs into block module")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org # 4.14+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
If we don't have the block layer enabled, we do not present card
status and extcsd in the debugfs.
Debugfs is not ABI, and maintaining files of no relevance for
non-block devices comes at a high maintenance cost if we shall
support it with the block layer compiled out.
The debugfs entries suffer from all the same starvation
issues as the other userspace things, under e.g. a heavy
dd operation.
The expected number of debugfs users utilizing these two
debugfs files is already low as there is an ioctl() to get the
same information using the mmc-tools, and of these few users
the expected number of people using it on SDIO or combo cards
are expected to be zero.
It is therefore logical to move this over to the block layer
when it is enabled, using the new custom requests and issue
it using the block request queue.
On the other hand it moves some debugfs code from debugfs.c
and into block.c.
Tested during heavy dd load by cat:in the status file.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
A significant amount of functions are available through the public mmc
host.h header file. Let's slim down this public mmc interface, as to
prevent users from abusing it, by moving some of the functions to private
mmc host.h header file.
This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
A significant amount of functions and other definitions are available
through the public mmc card.h header file. Let's slim down this public mmc
interface, as to prevent users from abusing it, by moving some of the
functions/definitions to private mmc header files.
This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Return error value for file_operations callback instead
of triggering BUG_ON which is meaningless. Personally I
don't believe n != EXT_CSD_STR_LEN could happen. Anyway,
propagate the error to the caller.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Clock frequency values written to an mmc host should not be less than
the minimum clock frequency which the mmc host supports.
Signed-off-by: Yuan Juntao <juntaox.yuan@intel.com>
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
MMC_CLKGATE was once invented to save power by gating the bus clock at
request inactivity. At that time it served its purpose. The modern way to
deal with power saving for these scenarios, is by using runtime PM.
Nowadays, several host drivers have deployed runtime PM, but for those
that haven't and which still cares power saving at request inactivity,
it's certainly time to deploy runtime PM as it has been around for several
years now.
To simplify code to mmc core and thus decrease maintenance efforts, this
patch removes all code related to MMC_CLKGATE.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
This patch add MMC_TIMING_UHS_SDR12 and MMC_TIMING_UHS_SDR25
for mmc_ios_show to show the ios->timing if mmc card runs under
these two modes.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds HS400 mode support for eMMC5.0 device. HS400 mode is high
speed DDR interface timing from HS200. Clock frequency is up to 200MHz
and only 8-bit bus width is supported. In addition, tuning process of
HS200 is required to synchronize the command response on the CMD line
because CMD input timing for HS400 mode is the same as HS200 mode.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Jackey Shen <jackey.shen@amd.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Current implementation for bus speed mode selection is too
complicated. This patch is to simplify the codes and remove
some duplicate parts.
The following changes are including:
* Adds functions for each mode selection(HS, HS-DDR, HS200 and etc)
* Rearranged the mode selection sequence with supported device type
* Adds maximum speed for HS200 mode(hs200_max_dtr)
* Adds field definition for HS_TIMING of EXT_CSD
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Once the mmc blkdevice is being probed, runtime pm will be enabled.
By using runtime autosuspend, the power save operations can be done
when request inactivity occurs for a certain time. Right now the
selected timeout value is set to 3 s. Obviously this value will likely
need to be configurable somehow since it needs to be trimmed depending
on the power save algorithm.
For SD-combo cards, we are still leaving the enablement of runtime PM
to the SDIO init sequence since it depends on the capabilities of the
SDIO func driver.
Moreover, when the blk device is being suspended, we make sure the device
will be runtime resumed. The reason for doing this is that we want the
host suspend sequence to be unaware of any runtime power save operations
done for the card in this phase. Thus it can just handle the suspend as
the card is fully powered from a runtime perspective.
Finally, this patch prepares to make it possible to move BKOPS handling
into the runtime callbacks for the mmc bus_ops. Thus IDLE BKOPS can be
accomplished.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
ext_csd exported through debugfs is printed in reverse order (from
byte 511 to 0), which causes confusion.
Fix the for loop to print ext_csd in natural order.
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch adds the support of the HS200 bus speed for eMMC 4.5 devices.
The eMMC 4.5 devices have support for 200MHz bus speed. The function
prototype of the tuning function is modified to handle the tuning
command number which is different in sd and mmc case.
Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch is to expose the actual SDCLK frequency in
/sys/kernel/debug/mmcX/ios entry.
For example, if the max clk for a normal speed card is 20MHz this
is reported in /sys/kernel/debug/mmcX/ios. Unfortunately the actual
SDCLK frequency (i.e. Baseclock / divisor) is not reported at all:
for example, in that case, on Arasan HC, it should be 48/4=12 (MHz).
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
These two basic defines were everywhere, simply because module.h
was also everywhere. But we are cleaning up the latter. So make
the exporters actually call out their need for the include.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Commit "mmc: add module param to set fault injection attributes" adds
a module_param to this file. But it is relying on the old implicit
"module.h is everywhere" behaviour, and without the explicit include
of moduleparam.h, the pending module.h split up produces this error:
core/debugfs.c:28:35: error: expected ')' before numeric constant
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Replace setup("fail_mmc_request") and faulty "ifdef KERNEL" with
a simple module_param(). The module param mmc_core.fail_request
may be used to set the fault injection attributes during boot time
or module load time.
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>