Host Controller needs tuning during initialization to operate SDR50
and SDR104 UHS-I cards. Whether SDR50 mode actually needs tuning is
indicated by bit 45 of the Host Controller Capabilities register.
A new command CMD19 has been defined in the Physical Layer spec
v3.01 to request the card to send tuning pattern.
We enable Buffer Read Ready interrupt at the very begining of tuning
procedure, because that is the only interrupt generated by the Host
Controller during tuning. We program the block size to 64 in the
Block Size register. We make sure that DMA Enable and Multi Block
Select in the Transfer Mode register are set to 0 before actually
sending CMD19. The tuning block is sent by the card to the Host
Controller using DAT lines, so we set Data Present Select (bit 5) in
the Command register. The Host Controller is responsible for doing
the verfication of tuning block sent by the card at the hardware
level. After sending CMD19, we wait for Buffer Read Ready interrupt.
In case we don't receive an interrupt after the specified timeout
value, we fall back on fixed sampling clock by setting Execute
Tuning (bit 6) and Sampling Clock Select (bit 7) of Host Control2
register to 0. Before exiting the tuning procedure, we disable Buffer
Read Ready interrupt and re-enable other interrupts.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Since only UHS-I cards respond with S18A set in response to ACMD41,
we set the card as ultra-high-speed after successfull initialization.
We need to decide whether a card is SDXC based on the C_SIZE field
of CSDv2.0 register. According to Physical Layer spec v3.01, the
minimum value of C_SIZE for SDXC card is 00FFFFh.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
We decide on the current limit to be set for the card based on the
Capability of Host Controller to provide current at 1.8V signalling,
and the maximum current limit of the card as indicated by CMD6
mode 0. We then set the current limit for the card using CMD6 mode 1.
As per the Physical Layer Spec v3.01, the current limit switch is
only applicable for SDR50, SDR104, and DDR50 bus speed modes. For
other UHS-I modes, we set the default current limit of 200mA.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch adds support for setting UHS-I bus speed mode during UHS-I
initialization procedure. Since both the host and card can support
more than one bus speed, we select the highest speed based on both of
their capabilities. First we set the bus speed mode for the card using
CMD6 mode 1, and then we program the host controller to support the
required speed mode. We also set High Speed Enable in case one of the
UHS-I modes is selected. We take care to reset SD clock before setting
UHS mode in the Host Control2 register, and then re-enable it as per
the Host Controller spec v3.00. We then set the clock frequency for
the UHS-I mode selected.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
As per Host Controller spec v3.00, we reset SDCLK before setting
High Speed Enable, and then set it back to avoid generating clock
gliches. Before enabling SDCLK again, we make sure the clock is
stable, so we use sdhci_set_clock().
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch adds support for setting driver strength during UHS-I
initialization procedure. Since UHS-I cards set S18A (bit 24) in
response to ACMD41, we use this as a base for UHS-I initialization.
We modify the parameter list of mmc_sd_get_cid() so that we can
save the ROCR from ACMD41 to check whether bit 24 is set.
We decide whether the Host Controller supports A, C, or D driver
type depending on the Capabilities register. Driver type B is
suported by default. We then set the appropriate driver type for
the card using CMD6 mode 1. As per Host Controller spec v3.00, we
set driver type for the host only if Preset Value Enable in the
Host Control2 register is not set. SDHCI_HOST_CONTROL has been
renamed to SDHCI_HOST_CONTROL1 to conform to the spec.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
SD cards which conform to Physical Layer Spec v3.01 can support
additional Bus Speed Modes, Driver Strength, and Current Limit
other than the default values. We use CMD6 mode 0 to read these
additional card functions. The values read here will be used
during UHS-I initialization steps.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Host Controller v3.00 adds another Capabilities register. Apart
from other things, this new register indicates whether the Host
Controller supports SDR50, SDR104, and DDR50 UHS-I modes. The spec
doesn't mention about explicit support for SDR12 and SDR25 UHS-I
modes, so the Host Controller v3.00 should support them by default.
Also if the controller supports SDR104 mode, it will also support
SDR50 mode as well. So depending on the host support, we set the
corresponding MMC_CAP_* flags. One more new register. Host Control2
is added in v3.00, which is used during Signal Voltage Switch
procedure described below.
Since as per v3.00 spec, UHS-I supported hosts should set S18R
to 1, we set S18R (bit 24) of OCR before sending ACMD41. We also
need to set XPC (bit 28) of OCR in case the host can supply >150mA.
This support is indicated by the Maximum Current Capabilities
register of the Host Controller.
If the response of ACMD41 has both CCS and S18A set, we start the
signal voltage switch procedure, which if successfull, will switch
the card from 3.3V signalling to 1.8V signalling. Signal voltage
switch procedure adds support for a new command CMD11 in the
Physical Layer Spec v3.01. As part of this procedure, we need to
set 1.8V Signalling Enable (bit 3) of Host Control2 register, which
if remains set after 5ms, means the switch to 1.8V signalling is
successfull. Otherwise, we clear bit 24 of OCR and retry the
initialization sequence. When we remove the card, and insert the
same or another card, we need to make sure that we start with 3.3V
signalling voltage. So we call mmc_set_signal_voltage() with
MMC_SIGNAL_VOLTAGE_330 set so that we are back to 3.3V signalling
voltage before we actually start initializing the card.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Allows appropriately-privileged applications to send CMD (normal) and ACMD
(application-specific; preceded with CMD55) commands to cards/devices on
the mmc bus. This is primarily useful for enabling the security
functionality built in to every SD card.
It can also be used as a generic passthrough (e.g. to enable virtual
machines to control mmc bus devices directly). However, this use case has
not been tested rigorously. Generic passthrough testing was only conducted
for a few non-security opcodes to prove the feasibility of the passthrough.
Since any opcode can be sent using this passthrough, it is very possible to
render the card/device unusable. Applications that use this ioctl must
have CAP_SYS_RAWIO.
Security commands tested on TI PCIxx12 (SDHCI), Sigma Designs SMP8652 SoC,
TI OMAP3621/OMAP3630 SoC, Samsung S5PC110 SoC, Qualcomm MSM7200A SoC.
Signed-off-by: John Calixto <john.calixto@modsystems.com>
Reviewed-by: Andrei Warkentin <andreiw@motorola.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
To avoid lockdep warnings:
BUG: key dc90a520 not in .data!
------------[ cut here ]------------
WARNING: at /home/rabin/kernel/arm/kernel/lockdep.c:2701 sysfs_add_file_mode+0x4c/0xb0()
Modules linked in:
[<c004b5d8>] (unwind_backtrace+0x0/0xe4) from [<c0074f20>] (warn_slowpath_common+0x4c/0x64)
[<c0074f20>] (warn_slowpath_common+0x4c/0x64) from [<c0074f50>] (warn_slowpath_null+0x18/0x1c)
[<c0074f50>] (warn_slowpath_null+0x18/0x1c) from [<c0157fec>] (sysfs_add_file_mode+0x4c/0xb0)
[<c0157fec>] (sysfs_add_file_mode+0x4c/0xb0) from [<c02d61e4>] (mmc_add_disk+0x40/0x64)
[<c02d61e4>] (mmc_add_disk+0x40/0x64) from [<c02d64cc>] (mmc_blk_probe+0x188/0x1fc)
[<c02d64cc>] (mmc_blk_probe+0x188/0x1fc) from [<c02ce820>] (mmc_bus_probe+0x14/0x18)
...
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Chris Ball <cjb@laptop.org>
On HP laptops with JMicron 388 chip, the write-locked SD card isn't
detected correctly as read-only in many cases. This is because the
PRESENT_STATE register becomes unsable just after plugging, and it
returns the WRITE_PROTECT bit wrongly at the first read.
This patch fixes the read-only detection by adding a new sdhci quirk
indicating to check the register more intensively with a relatively
long delay.
The patch is tested with 2.6.39-rc4 kernel.
Cc: Aries Lee <arieslee@jmicron.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
With the hardware partitions support (which represent additional logical
devices present on MMC), devidx does not correspond with index used to form
/dev/mmcblkX names. So use an additional allocated index for device names.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Marvell pxa controllers have private registers that may need to be
modified before and after a reset is done.
For example, the SD reset operation, RESET_ALL, will reset the private
registers to their default state. This will cause the clock adjustment
registers that may have been programmed to have incorrect values.
RESET_DATA sometimes needs to be delayed before the reset is done
(depending on SoC) to enable any transactions being handled by the
SDIO card to be completed. Needed in pre SD 3.0 silicon to handle
clock gating.
Implement hooks to allow this to happen.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Commit 373e6a (mmc: sdhci: R1B command handling + MMC_CAP_ERASE) moved the
handling of SDHCI_QUIRK_TIMEOUT_USES_SDCLK from sdhci_calc_timeout() to
sdhci_add_host(). This causes division by zero errors on at least the S3C
SDHCI controller as the quirk implementation needs host->clock set to work
but host->clock has not been set when sdhci_add_host() is called.
Fix this by backing out that portion of the change, the clock may vary at
runtime anyway. It does occur to me that we may want to move the quirk to
where we set the clock but this seems more invasive and I'm concerned
about undesirable side effects.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Converts from:
struct mmc_request mrq;
memset(&mrq, 0, sizeof(struct mmc_request));
to:
struct mmc_request mrq = {0};
because it's shorter, as performant, and easier to work out whether
initialization has happened.
Signed-off-by: Chris Ball <cjb@laptop.org>
Converts from:
struct mmc_data data;
memset(&data, 0, sizeof(struct mmc_data));
to:
struct mmc_data data = {0};
because it's shorter, as performant, and easier to work out whether
initialization has happened.
Signed-off-by: Chris Ball <cjb@laptop.org>
Converts from:
struct mmc_command cmd;
memset(&cmd, 0, sizeof(struct mmc_command));
to:
struct mmc_command cmd = {0};
because it's shorter, as performant, and easier to work out whether
initialization has happened.
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc_cmd_app did not zero out mmc_command on stack.
Reported-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Some SD host controllers (noticed on an integrated JMicron SD reader on an
HP Pavilion dv5-1250eo laptop) don't update the dma address register before
signaling a dma interrupt due to a dma boundary. Update the register
manually to the next boundary (by default 512KiB), at which the transfer
stopped.
As long as each transfer is at most 512KiB in size (guaranteed by a BUG_ON
in sdhci_prepare_data()) and the boundary is kept at the default value,
this fix is needed at most once per transfer. Smaller boundaries are taken
care of by counting the transferred bytes.
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=28462
Signed-off-by: Mikko Vinni <mmvinni@yahoo.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Block quirks implemented using core/quirks.c support.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Allows device MMC boot partitions to be accessed. MMC partitions are
treated effectively as separate block devices on the same MMC card.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Move host claim/release into mmc_blk_issue_rq.
(This is helpful so that selecting partition only has to happen
in one place for these commands.)
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
CMD6 is an R1B-type command, where DAT is used as busy. Depending
on register written using CMD6, timeout value can be different
as per spec.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
ERASE command needs R1B response, so fix R1B-type command
handling for SDHCI controller. For non-DAT commands using a busy
response, the cmd->cmd_timeout_ms (in ms) field is used for timeout
calculations.
Based on patch by Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Renames erase_timeout to cmd_timeout_ms inside struct mmc_command.
First step to making host honor timeouts for non-data-transfer
commands. Cleans up erase timeout code.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
The current mechanism is SDIO-only. This allows us to create
function-specific quirks, without creating messy Kconfig dependencies,
or polluting core/ with function-specific code.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
led_trigger_register_simple() allocates memory which must not be leaked
in the error-path of mmc_add_host. Move it past the only error-check in
the function.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch fixes 21 errors and 6 warnings reported by checkpatch.pl.
Signed-off-by: Ameya Palande <2ameya@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
The wl12xx device supports disconnecting the pull-up resistor on
CD/DAT[3] (pin 1) of the card.
Tell SDIO core to disconnect that resistor during card init,
since we don't need it at that point (and anyway all
hosts shall provide pull-up resistors on all data lines DAT[3:0]
as described in section 6 of the SD physical specification).
As a result, this may save some power, but it's also generally healthy
since it prevents both ends from pulling up that pin, which
results in undesirable asymmetric physical bus.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
006ebd5d introduced sdio_disable_cd(), which disconnects the pull-up
resistor on CD/DAT[3] (pin 1) of the card.
Make it possible to start using sdio_disable_cd() by introducing
MMC_QUIRK_DISABLE_CD.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Tell SDIO core to ignore the standard SDIO function interface
codes indicated by the wl1271. This is required because the
wl1271 erroneously indicates its first function as a standard
Bluetooth SDIO interface, and that drives btsdio mad.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Introduce MMC_QUIRK_NONSTD_FUNC_IF to ignore the "SDIO Standard Function
interface code" as indicated by the card's FBR, and instead treat all
functions as non-standard interfaces.
This is required to prevent standard drivers from facing
errors when trying to communicate with SDIO cards that erroneously
indicate standard function interface codes.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
6b5eda36 followed SDIO spec part E1 section 8, which states that
in case SDIO interrupts are being used to wake up a suspended host,
then it is required to switch to 1-bit mode before stopping the clock.
Before switching to 1-bit mode (or back to 4-bit mode on resume),
make sure that SDIO interrupts are really being used to wake the host.
This is helpful for devices which have an external irq line (e.g.
wl1271), and do not use SDIO interrupts to wake up the host.
In this case, switching to 1-bit mode (and back to 4-bit mode on resume)
is not necessary.
Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc_card_is_powered_resumed is a mouthful; instead, simply use
mmc_card_keep_power, which also better explains the purpose of
the macro.
Employ mmc_card_keep_power() where possible.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Allows reliable writes to be used for MMC writes. Reliable writes are used
to service write REQ_FUA/REQ_META requests. Handles both the legacy and
the enhanced reliable write support in MMC cards.
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
This config option is used to decide whether tegra sdhci support
should be build into the sdhci-platform module. So setting it 'm'
is nonsense, since we can't build part of an module as a module.
The effect for 'm' will probably be the same as for 'n'.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Enable fast bcm4329 WIFI suspend/resume on Tegra2 board.
This patch allows the mach-tegra support to tell the tegra MMC host
controller to NOT turn off power for the MMC controller the WIFI part
lives behind. Thus bcm4329 firmware doesn't need to be reloaded.
Signed-off-by: Venkat Rao <vrao@broadcom.com>
Tested-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Chris Ball <cjb@laptop.org>
There is no need to disable irq's when using the sg_copy_*_buffer()
functions because those functions do that already. There are also
no races for the mm_queue struct here that would require the irq's
to be disabled before calling sg_copy_*_buffer().
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
uBoot sometimes leaves eMMC pointing to the private boot partition.
Ensure we always start looking at the user partition.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Bruce Clemens <bpclemens@marvell.com>
Signed-off-by: Mark F. Brown <markb@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Commit b826291c, "drivercore/dt: add a match table pointer to struct
device" added an of_match pointer to struct device to cache the
of_match_table entry discovered at driver match time. This was unsafe
because matching is not an atomic operation with probing a driver. If
two or more drivers are attempted to be matched to a driver at the
same time, then the cached matching entry pointer could get
overwritten.
This patch reverts the of_match cache pointer and reworks all users to
call of_match_device() directly instead.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This fixes a regression on high clock speeds with the MMCI on
ux500. We need to make sure we derive the passthru clock on the
falling edge of the incoming clock if it shall work at high
frequencies, and on the ux500's there is a special bit for this.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The mmci.h header contained a few registers not clearly marked
as ST Micro only, rectify this and remove the HWFC magic in the
process. The idea is to make the mmci.h header file more ordered
so other vendors with PL180 derivates can see where to put in
their custom register defines.
Includes portions of an earlier patch from Sebastian Rasmussen.
Acked-by: Sebastian Rasmussen <sebastian.rasmussen@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Saves about 50KB of data.
Old/new size of all objects:
text data bss dec hex filename
563015 80096 130684 773795 bcea3 (TOTALS)
610916 32256 130632 773804 bceac (TOTALS)
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Kurt Van Dijck <kurt.van.dijck@eia.be> (for drivers/net/can/softing/softing_cs.c)
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
It seems that under certain circumstances the sdhci_tasklet_finish()
call can be entered with mrq set to NULL, causing the system to crash
with a NULL pointer de-reference.
Seen on S3C6410 system. Based on a patch by Dimitris Papastamos.
Reported-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
It seems that under certain circumstances that the sdhci_tasklet_finish()
call can be entered with mrq->cmd set to NULL, causing the system to crash
with a NULL pointer de-reference.
Unable to handle kernel NULL pointer dereference at virtual address 00000000
PC is at sdhci_tasklet_finish+0x34/0xe8
LR is at sdhci_tasklet_finish+0x24/0xe8
Seen on S3C6410 system.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Arindam Nath