i2c event of next read/write byte may trigger before current int state
is cleared in the interrupt handler. So, this should be done at the
beginning of interrupt handler to avoid losing new i2c events.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
There isn't much point in managing our own custom timeout timer when the
completion interface already includes support for it. This makes the
resulting code much simpler and robust.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The S3C I2C controller indicates completion of I2C transfers before
the bus has a stop condition on it. In order to ensure that we do not
attempt to start a new transfer before the bus is idle the driver
currently inserts a 1ms delay. This is vastly larger than is generally
required and has a visible effect on performance under load, such as
when bringing up audio CODECs or reading back status information with
non-bulk I2C reads.
Replace the sleep with a spin on the IIC status register for up to 1ms.
This will busy wait but testing on my SMDK6410 system indicates that
the overwhelming majority of transactions complete on the first spin,
with maximum latencies of less than 10 spins so the absolute overhead
of busy waiting should be at worst comprable to msleep(), and the
overall system performance is dramatically improved.
The main risk is poor interaction with multimaster systems where
we may miss the bus going idle before the next transaction. Defend
against this by falling back to the original 1ms delay after 20 spins.
The overall effect in my testing is an approximately 20% improvement
in kernel startup time.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc: Define ARCH_SLAB_MINALIGN
drivers/sbus/char/flash.c: flash_read should update ppos instead of file->f_pos
sparc64: Fix stack dumping and tracing when function graph is enabled.
sparc64: Show stack backtrace from show_regs() just like other platforms.
* 'davinci-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-davinci: (48 commits)
Revert "rtc: omap: let device wakeup capability be configured from chip init logic"
DM365: Added more PINMUX configurations for AEMIF
DM365: Make CLKOUTx available
DM365: Added PINMUX definitions for GPIO30..32
Davinci: iotable based ioremap() interception
Davinci: pinmux - use ioremap()
Davinci: aintc/cpintc - use ioremap()
Davinci: psc - use ioremap()
Davinci: timer - use ioremap()
Davinci: jtag_id - use ioremap()
Davinci: da8xx: rtc - use ioremap
Davinci: gpio - use ioremap()
davinci: edma: fix coding style issue related to breaking lines
davinci: edma: use BIT() wherever possible
davinci: edma: fix coding style issue related to usage of braces
davinci: edma: use a more intuitive name for edma_info
Davinci: serial - conditional reset via pwremu
Davinci: serial - use ioremap()
Davinci: serial - remove unnecessary define
Davinci: watchdog reset separation across socs
...
Fix up trivial conflict in arch/arm/Kconfig due to removal of "select
GENERIC_TIME"
Commit a45185d2d "cpumask: convert kernel/compat.c" broke libnuma, which
abuses sched_getaffinity to find out NR_CPUS in order to parse
/sys/devices/system/node/node*/cpumap.
On NUMA systems with less than 32 possibly CPUs, the current
compat_sys_sched_getaffinity now returns '4' instead of the actual
NR_CPUS/8, which makes libnuma bail out when parsing the cpumap.
The libnuma call sched_getaffinity(0, bitmap, 4096) at first. It mean
the libnuma expect the return value of sched_getaffinity() is either len
argument or NR_CPUS. But it doesn't expect to return nr_cpu_ids.
Strictly speaking, userland requirement are
1) Glibc assume the return value mean the lengh of initialized
of mask argument. E.g. if sched_getaffinity(1024) return 128,
glibc make zero fill rest 896 byte.
2) Libnuma assume the return value can be used to guess NR_CPUS
in kernel. It assume len-arg<NR_CPUS makes -EINVAL. But
it try len=4096 at first and 4096 is always bigger than
NR_CPUS. Then, if we remove strange min_length normalization,
we never hit -EINVAL case.
sched_getaffinity() already solved this issue. This patch adapts
compat_sys_sched_getaffinity() to match the non-compat case.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Ken Werner <ken.werner@web.de>
Cc: stable@kernel.org
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] Drop duplicated "config IOMMU_HELPER"
[IA64] invoke oom-killer from page fault
[IA64] use __ratelimit
[IA64] Use set_cpus_allowed_ptr
[IA64] Use set_cpus_allowed_ptr
[IA64] arch/ia64/hp/common/sba_iommu.c: Rename dev_info to adi
[IA64] removing redundant ifdef
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (224 commits)
ARM: remove 'select GENERIC_TIME'
ARM: 6136/1: ARCH_REQUIRE_GPIOLIB selects GENERIC_GPIO
ARM: 6074/1: oprofile: convert from sysdev to platform device
ARM: 6073/1: oprofile: remove old files and update KConfig
ARM: 6072/1: oprofile: use perf-events framework as backend
ARM: 6071/1: perf-events: allow modules to query the number of hardware counters
ARM: 6070/1: perf-events: add support for xscale PMUs
ARM: 6069/1: perf-events: use numeric ID to identify PMU
ARM: 6064/1: pmu: register IRQs at runtime
ARM: Optionally allow ARMv6 to use 'normal, bufferable' memory for DMA
ARM: 6134/1: Handle instruction cache maintenance fault properly
ARM: nwfpe: allow debugging output to be configured at runtime
ARM: rename mach_cpu_disable() to platform_cpu_disable()
ARM: 6132/1: PL330: Add common core driver
ARM: 6094/1: Extend cache-l2x0 to support the 16-way PL310
ARM: Move memory mapping into mmu.c
ARM: Ensure meminfo is sorted prior to sanity_check_meminfo
ARM: Remove useless linux/bootmem.h includes
ARM: convert /proc/cpu/aligment to seq_file
arm: use asm-generic/scatterlist.h
...
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (127 commits)
sh: update defconfigs.
sh: Fix up the NUMA build for recent LMB changes.
sh64: provide a stub per_cpu_trap_init() definition.
sh: fix up CONFIG_KEXEC=n build.
sh: fixup the docbook paths for clock framework shuffling.
driver core: Early dev_name() depends on slab_is_available().
sh: simplify WARN usage in SH clock driver
sh: Check return value of clk_get on ms7724
sh: Check return value of clk_get on ecovec24
sh: move sh clock-cpg.c contents to drivers/sh/clk-cpg.c
sh: move sh clock.c contents to drivers/sh/clk.
sh: move sh asm/clock.h contents to linux/sh_clk.h V2
sh: remove unused clock lookup
sh: switch boards to clkdev
sh: switch sh4-202 to clkdev
sh: switch shx3 to clkdev
sh: switch sh7757 to clkdev
sh: switch sh7763 to clkdev
sh: switch sh7780 to clkdev
sh: switch sh7786 to clkdev
...
Separate out ata_bmdma_qc_issue() from ata_sff_qc_issue() such that
ata_sff_qc_issue() only deals with non-BMDMA SFF protocols (PIO and
nodata) while ata_bmdma_qc_issue() deals with the BMDMA protocols and
uses ata_sff_qc_issue() for non-DMA commands. All the users are
updated accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
struct ata_prd and ap->prd are BMDMA specific. Add bmdma_ prefix to
them and move them inside CONFIG_ATA_SFF.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Both qc_prep functions deal only with BMDMA PRD setup and PIO only SFF
drivers don't need them. Rename to ata_bmdma_[dumb_]qc_prep() and
relocate.
All usages are renamed except for pdc_adma and sata_qstor. Those two
drivers are not BMDMA drivers and don't need to call BMDMA qc_prep
functions. Calls to ata_sff_qc_prep() in the two drivers are removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some of error handling logic in ata_sff_error_handler() and all of
ata_sff_post_internal_cmd() are for BMDMA. Create
ata_bmdma_error_handler() and ata_bmdma_post_internal_cmd() and move
BMDMA part into those.
While at it, change DMA protocol check to ata_is_dma(), fix
post_internal_cmd to call ap->ops->bmdma_stop instead of directly
calling ata_bmdma_stop() and open code hardreset selection so that
ata_std_error_handler() doesn't have to know about sff hardreset.
As these two functions are BMDMA specific, there's no reason to check
for bmdma_addr before calling bmdma methods if the protocol of the
failed command is DMA. sata_mv and pata_mpc52xx now don't need to set
.post_internal_cmd to ATA_OP_NULL and pata_icside and sata_qstor don't
need to set it to their bmdma_stop routines.
ata_sff_post_internal_cmd() becomes noop and is removed.
This fixes p3 described in clean-up-BMDMA-initialization patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
port_task is tightly bound to the standard SFF PIO HSM implementation.
Using it for any other purpose would be error-prone and there's no
such user and if some drivers need such feature, it would be much
better off using its own. Move it inside CONFIG_ATA_SFF and rename it
to sff_pio_task.
The only function which is exposed to the core layer is
ata_sff_flush_pio_task() which is renamed from ata_port_flush_task()
and now also takes care of resetting hsm_task_state to HSM_ST_IDLE,
which is possible as it's now specific to PIO HSM.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
ap->[last_]ctl are specific to SFF controllers. Put them inside
CONFIG_ATA_SFF and move initialization into ata_sff_port_init().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
In preparation of proper SFF/BMDMA separation, introduce
ata_sff_init/exit() and ata_sff_port_init(). These functions
currently don't do anything.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Sonic Zhang
Michael Hennerich
Mark Brown
Linus Torvalds
KOSAKI Motohiro
Kevin Hilman
Dmitry Torokhov
Tejun Heo