Before this patch, we always used only single sg entry for SDIO transfer.
This patch switches to using multiple sg entries. In the case of dwmci,
it supports only up to 4KB size per single sg entry. So if we want to
transfer more than 4KB, we should send more than 1 command.
When we tested before applying this patch, it took around 335 us for
5K(5120) bytes transfer with dwmci controller. After applying this patch,
it takes 242 us for 5K bytes. So this patch makes around 38% performance
improvement for 5K bytes transfer. If the transfer size is bigger, then
the performance improvement ratio will be increased.
Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
There are infinite loops in the mmc code that can be caused by bad
hardware. The code will loop forever if the device never comes back
from program mode, R1_STATE_PRG, and it is not ready for data,
R1_READY_FOR_DATA.
A long timeout is added to prevent the code from looping forever.
The timeout will occur if the device never comes back from program
state or the device never becomes ready for data.
It's not clear whether the timeout will do more than log a pr_err()
and then start a fresh hang all over again. We may need to extend
this patch later to perform some kind of reset of the device (is
that possible?) or rejection of new I/O to the device.
Signed-off-by: Trey Ramsay <tramsay@linux.vnet.ibm.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
The patch "dw_mmc: fix multiple drv_data NULL dereferences" has
unfortunately clashed with my "mmc: dw_mmc: constify dw_mci_idmac_ops
in exynos back-end" patch, causing new warnings to appear.
This should hopefully fix the issue for good.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
The at91-mci driver is not needed anymore since the atmel-mci driver now
supports all Atmel devices.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
MMC debounce clock is applicable only for omap2430, warning message gets
printed when enable fails for debounce clock. Remove the get debounce clock
failure message as it is noisy for other platforms.
Signed-off-by: Balaji T K <balajitk@ti.com>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Maximum bus frequency can be limited by external circuitry like level
shifters etc. Allow passing this value from DT.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This allows DT-driven board to set up the pin mux only when the driver
is in use.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
When a SD card is initialized some data transfers of 64 and 8 bytes
are issued. It seems the DMA has some problems dealing with these kind
of "short" transfers, leading sometimes to the SD card not being detected.
In order to solve this problem, do not use DMA for transfer sizes lower
than the sector size.
Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Since v3.2 we have nice macro to define the platform driver's init and exit
calls. This patch simplifies the dw_mmc platform driver by using that macro.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Girish K S <girish.shivanajappa@linaro.org>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Girish K S <girish.shivananjappa@linaro.org>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
In case both 'req' and 'mq->mqrq_prev->req' are null, there is no request
to be processed. That means there is no need to switch buffer.
Switching buffer is required only after finishing 'issue_fn'.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Per Forlin <per.forlin@stericsson.com>
Tested-by: Johan Rudholm <johan.rudholm@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
On some systems, e.g., kzm9g, MMCIF interfaces can produce spurious
interrupts without any active request. To prevent the Oops, that results
in such cases, don't dereference the mmc request pointer until we make
sure, that we are indeed processing such a request.
Reported-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
Cc: stable@vger.kernel.org
Signed-off-by: Chris Ball <cjb@laptop.org>
The vmmc regulator enable in sdhci_add_host is NOT necessary since
it can be enabled during mmc_power_up by function mmc_regulator_set_ocr.
And this extra enable will make regulator_enable/regulator_disable
unbalanced. Consequently, vmmc can't be disabled during mmc_power_off.
Also, if the vqmmc regulator exists, it should be enabled regardless it
support 1.8v or not.
Signed-off-by: Kevin Liu <kliu5@marvell.com>
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This reverts commit 8464dd52d3, which was a misapplied debugging
version of the patch, not the final patch itself.
Signed-off-by: Chris Ball <cjb@laptop.org>
Cc: stable@vger.kernel.org
2abeb5c5de ("Add clk_(enable/disable) in runtime suspend/resume")
added the capability to stop the clocks when the device is runtime
suspended, but forgot to handle the case of the card-detect using
an external gpio.
Therefore in the case that runtime-pm is enabled, start the io-clock
when a card is inserted and stop it again once it is removed.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Pull MIPS fixes from Ralf Baechle:
"These are the fixes for the N32 syscall bugs found by Al, an
extraneous break that broke detection for R3000 and R3081 processors,
an endless loop processing signals for kernel task (x86 received the
same fix a while ago) and a fix for transparent huge page which took
ages to track down because it was so hard to come up with a workable
test case."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: Fix endless loop when processing signals for kernel tasks
MIPS: R3000/R3081: Fix CPU detection.
MIPS: N32: Fix signalfd4 syscall entry point
MIPS: N32: Fix preadv(2) and pwritev(2) entry points.
MIPS: Avoid mcheck by flushing page range in huge_ptep_set_access_flags()
Pull build fix from Rusty Russell:
"Tim Gardner <tim.gardner@canonical.com> writes:
> It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c.
> The object file cannot be built until $(obj)/oid_registry_data.c has been
> generated.
>
> A periodic and hard to reproduce parallel build failure is due to
> this incorrect lib/Makefile dependency. The compile error is completely
> disingenuous.
>
> GEN lib/oid_registry_data.c
> Compiling 49 OIDs
> CC lib/oid_registry.o
> gcc: error: lib/oid_registry.c: No such file or directory
> gcc: fatal error: no input files
> compilation terminated.
> make[3]: *** [lib/oid_registry.o] Error 4
I can't reproduce it either. It's completely weird; nothing ever
removes lib/oid_registry.c, so either gcc is giving the wrong message
or it's a weird fs with a very odd race.
But your version is definitely more correct than the previous one,
so..."
* 'more-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
lib/Makefile: Fix oid_registry build dependency
Pull module signing fixes from Rusty Russell:
"David gave me these a month ago, during my git workflow churn :("
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
ASN.1: Fix an indefinite length skip error
MODSIGN: Don't use enum-type bitfields in module signature info block
Pull watchdog fix from Thomas Gleixner:
"Trivial CPU hotplug regression fix for the watchdog code"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
watchdog: Fix CPU hotplug regression
Merely reorganizing documentation. No functional changes. It makes more
sense for the gpio-leds binding to be grouped with other led bindings
than with gpio drivers.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c.
The object file cannot be built until $(obj)/oid_registry_data.c has been
generated.
A periodic and hard to reproduce parallel build failure is due to
this incorrect lib/Makefile dependency. The compile error is completely
disingenuous.
GEN lib/oid_registry_data.c
Compiling 49 OIDs
CC lib/oid_registry.o
gcc: error: lib/oid_registry.c: No such file or directory
gcc: fatal error: no input files
compilation terminated.
make[3]: *** [lib/oid_registry.o] Error 4
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This updates the IRQdomain documentation a bit, by adding a more
verbose explanation to why we need this, and by adding some
extended documentation of the irq_domain_simple() usecase.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The "powervr" prefix which is currently described as "Imagination
Technologies" isn't really appropriate for non-PowerVR hardware, so
deprecate it, changing the description of "powervr" to "PowerVR
(deprecated, use img)", and add a separate "img" prefix for "Imagination
Technologies Ltd.".
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The problem occurs [1] when a kernel-mode task returns from a system
call with a pending signal.
A real-life scenario is a child of 'khelper' returning from a failed
kernel_execve() in ____call_usermodehelper() [ kernel/kmod.c ].
kernel_execve() fails due to a pending SIGKILL, which is the result of
"kill -9 -1" (at least, busybox's init does it upon reboot).
The loop is as follows:
* syscall_exit_work:
- work_pending: // start_of_the_loop
- work_notifysig:
- do_notify_resume()
- do_signal()
- if (!user_mode(regs)) return;
- resume_userspace // TIF_SIGPENDING is still set
- work_pending // so we call work_pending => goto
// start_of_the_loop
More information can be found in another LKML thread:
http://www.serverphorums.com/read.php?12,457826
[1] The problem was also reproduced on !CONFIG_VM86 x86, and the
following fix was accepted.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=29a2e2836ff9ea65a603c89df217f4198973a74f
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3571/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Broken since e05ea74fc56f347f872ef9946d27c53e8bf20864 (lmo) rsp.
cea7e2dfde (kernel.org) [MIPS: Sort out CPU
type to name translation.] These CPUs are no longer very popular to say
the least ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Murphy McCauley <murphy.mccauley@gmail.com>
This needs to use the compat entry point or it's going to fail on big
endian systems.
Noticed by Al Viro.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Set chan_mux[DA9055_ADC_ADCIN3] = DA9055_ADC_MUX_ADCIN3.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This is the HWMON patch for DA9055 PMIC and has got dependency on the
DA9055 MFD core.
This patch monitors the DA9055 PMIC's ADC channels vddout, junction temperature
and auxiliary channels.
This patch is functionally tested on Samsung SMDKV6410.
Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
[Guenter Roeck: Dropped __devinit, __devexit, __devexit_p]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Since N4xx, N5xx, D4xx, and D5xx are now reliably detected using the model ID
and the stepping/mask, drop the respective entries from tjmax_table.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
Make the code easier to extend and easier to adjust by using a model table
listing CPU models, stepping/mask, and associated TjMax.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
So far, we use the NM10 Express Chipset PCI chip ID to detect TjMax for
Atom CPUs with model 0x1c. As it turns out, we can use the CPU stepping
(x86_mask) for the same purpose; stepping is 10 for all model 0x1c CPUs
with TjMax of 100 degrees C. This was verified by checking the output of
/proc/cpuinfo for the respective CPUs (D4xx, D5xx, N4xx, N5xx).
Other CPUs currently covered by the same code (Exx, Z6xx, Z2460) are not
supported by the NM10 Express Chipset. Most of those CPUs have TjMax of 90
degrees C, except for E6xxT models which have a TjMax of 110 degrees C.
E6xxT CPUs can however not be detected by software.
Calculate TjMax for Atom CPUs as follows. Note that the listed values are not
correct in some cases (230, 330). tjmax_table is used for those to override
the default values.
ID Stepping TjMax Models
0x1c 10 100 D4xx, N4xx, D5xx, N5xx
0x1c not 10 90 Z5xx, N2xx, 230, 330, others
0x26 - 90 Atom Tunnel Creek (Exx),
Lincroft (Z6xx)
0x27 - 90 Atom Medfield (Z2460)
0x36 - 100 Atom Cedar Trail (N2xxx, D2xxx)
Also drop the module dependency on PCI.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
Use the module_i2c_driver() macro to make the code smaller
and a bit simpler.
dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The ADS7830 device is almost the same as the ADS7828,
except that it does 8-bit sampling, instead of 12-bit.
This patch extends the ads7828 driver to support this chip.
Signed-off-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
As there is no reliable way to identify the chip, it is preferable to
remove the detect callback, to avoid misdetection.
Module parameters are not worth it here, so let's get rid of them and
add an ads7828_platform_data structure instead.
Clean the code by removing unused macros, fixing coding style issues,
avoiding function prototypes and using convenient macros such as
module_i2c_driver().
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add family 16h PCI ID to AMD's power driver to allow it report
power consumption on these processors.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
READ is zero so the "rw & READ" test is always false. The intended test
was "((rw & RW_MASK) == READ)".
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix an error in asn1_find_indefinite_length() whereby small definite length
elements of size 0x7f are incorrecly classified as non-small. Without this
fix, an error will be given as the length of the length will be perceived as
being very much greater than the maximum supported size.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Don't use enum-type bitfields in the module signature info block as we can't be
certain how the compiler will handle them. As I understand it, it is arch
dependent, and it is possible for the compiler to rearrange them based on
endianness and to insert a byte of padding to pad the three enums out to four
bytes.
Instead use u8 fields for these, which the compiler should emit in the right
order without padding.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Norbert reported:
"3.7-rc6 booted with nmi_watchdog=0 fails to suspend to RAM or
offline CPUs. It's reproducable with a KVM guest and physical
system."
The reason is that commit bcd951cf(watchdog: Use hotplug thread
infrastructure) missed to take this into account. So the cpu offline
code gets stuck in the teardown function because it accesses non
initialized data structures.
Add a check for watchdog_enabled into that path to cure the issue.
Reported-and-tested-by: Norbert Warmuth <nwarmuth@t-online.de>
Tested-by: Joseph Salisbury <joseph.salisbury@canonical.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1211231033230.2701@ionos
Link: http://bugs.launchpad.net/bugs/1079534
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This fixes a bit error in the U8500 clock implementation: the
unused p2_pclk12 registered at bit 12 in periphereral group 6
was defined as using bit 11 rather than bit 12.
When walking over and disabling the unused clocks in the tree
at late init time, p2_pclk12 was disabled, by effectively
clearing the but for p2_pclk11 instead of bit 12 as it should
have, thus disabling gpio block 6 and 7.
Reported-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Philippe Begnic <philippe.begnic@st.com>
Cc: stable@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Pull module fixes from Rusty Russell:
"Module signing build fixes for blackfin and metag"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
modsign: add symbol prefix to certificate list
linux/kernel.h: define SYMBOL_PREFIX
code:
1. The UBI background thread got stuck when a bit-flip happened because free
LEBs was not removed from the "free" tree when we started using it.
2. I/O debugging checks did not work because we called a sleeping function in
atomic context.
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Merge tag 'upstream-3.7-rc9' of git://git.infradead.org/linux-ubi
Pull UBI changes from Artem Bityutskiy:
"Fixes for 2 brown-paperbag bugs introduced this merge window by the
fastmap code:
1. The UBI background thread got stuck when a bit-flip happened
because free LEBs was not removed from the "free" tree when we
started using it.
2. I/O debugging checks did not work because we called a sleeping
function in atomic context."
* tag 'upstream-3.7-rc9' of git://git.infradead.org/linux-ubi:
UBI: dont call ubi_self_check_all_ff() in __wl_get_peb()
UBI: remove PEB from free tree in get_peb_for_wl()
Pull workqueue fixes from Tejun Heo:
"So, safe fixes my ass.
Commit 8852aac25e ("workqueue: mod_delayed_work_on() shouldn't queue
timer on 0 delay") had the side-effect of performing delayed_work
sanity checks even when @delay is 0, which should be fine for any sane
use cases.
Unfortunately, megaraid was being overly ingenious. It seemingly
wanted to use cancel_delayed_work_sync() before cancel_work_sync() was
introduced, but didn't want to waste the space for full delayed_work
as it was only going to use 0 @delay. So, it only allocated space for
struct work_struct and then cast it to struct delayed_work and passed
it into delayed_work functions - truly awesome engineering tradeoff to
save some bytes.
Xiaotian fixed it by making megraid allocate full delayed_work for
now. It should be converted to use work_struct and cancel_work_sync()
but I think we better do that after 3.7.
I added another commit to change BUG_ON()s in __queue_delayed_work()
to WARN_ON_ONCE()s so that the kernel doesn't crash even if there are
more such abuses."
* 'for-3.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s
megaraid: fix BUG_ON() from incorrect use of delayed work
By using the native syscall entry point the kernel was also expecting
64-bit iovec structures.
This is broken since ddd9e91b71 [preadv/
pwritev: MIPS: Add preadv(2) and pwritev(2) syscalls.] which originally
added these two syscalls. I walked through piles of code, including
libc and couldn't find anything that would have worked around the issue
so this change the API to what it should always have been.
Noticed and patch suggested by Al Viro.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull sparc fixes from David Miller:
"Two small fixes for Sparc, nobody uses sparc, so these are low risk :-)
1) Piggyback is too picky about the symbol types that _start and _end
have in the final kernel image, and it thus breaks with newer
binutils. Future proof by getting rid of the symbol type checks.
2) exit_group() should kill register windows on sparc64 the same way
we do for plain exit(). Thanks to Al Viro for spotting this."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: Fix piggyback with newer binutils.
sparc64: exit_group should kill register windows just like plain exit.
The block device access simplification that avoided accessing the (racy)
block size information (commit bbec0270bd: "blkdev_max_block: make
private to fs/buffer.c") no longer checks the maximum block size in the
block mapping path.
That was _almost_ as simple as just removing the code entirely, because
the readers and writers all check the size of the device anyway, so
under normal circumstances it "just worked".
However, the block size may be such that the end of the device may
straddle one single buffer_head. At which point we may still want to
access the end of the device, but the buffer we use to access it
partially extends past the end.
The 'bd_set_size()' function intentionally sets the block size to avoid
this, but mounting the device - or setting the block size by hand to
some other value - can modify that block size.
So instead, teach 'submit_bh()' about the special case of the buffer
head straddling the end of the device, and turning such an access into a
smaller IO access, avoiding the problem.
This, btw, also means that unlike before, we can now access the whole
device regardless of device block size setting. So now, even if the
device size is only 512-byte aligned, we can read and write even the
last sector even when having a much bigger block size for accessing the
rest of the device.
So with this, we could now get rid of the 'bd_set_size()' block size
code entirely - resulting in faster IO for the common case - but that
would be a separate patch.
Reported-and-tested-by: Romain Francoise <romain@orebokech.com>
Reporeted-and-tested-by: Meelis Roos <mroos@linux.ee>
Reported-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
