Bjorn Helgaas [Tue, 8 May 2007 07:36:07 +0000 (00:36 -0700)]
x86, serial: convert legacy COM ports to platform devices
Make x86 COM ports into platform devices and don't probe for them
if we have PNP.
This prevents double discovery, where a device was found both by
the legacy probe and by 8250_pnp, e.g.,
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:02: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
This also means IRDA devices without a UART PNP ID will no longer be
claimed by the serial driver, which might require changes in IRDA
drivers and administration.
In addition to this patch, you may need to configure a setserial init
script, e.g., /etc/init.d/setserial, so it doesn't poke legacy UART
stuff back in. On Debian, "dpkg-reconfigure setserial" with the "kernel"
option does this.
To force the old legacy probe behavior even when we have PNPBIOS or
ACPI, load the new legacy_serial module (or build 8250 static) with
the "legacy_serial.force" option.
[akpm@linux-foundation.org: fix makefiles] Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Keith Owens <kaos@ocs.com.au> Cc: Len Brown <lenb@kernel.org> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Matthieu CASTET <castet.matthieu@free.fr> Cc: Jean Tourrilhes <jt@hpl.hp.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Ville Syrjala <syrjala@sci.fi> Cc: Russell King <rmk+serial@arm.linux.org.uk> Cc: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bjorn Helgaas [Tue, 8 May 2007 07:36:05 +0000 (00:36 -0700)]
smsc-ircc2: add PNP support
Claim devices using PNP, unless the user explicitly specified device
addresses. This can be disabled with the "smsc-ircc2.nopnp" option.
This removes the need for probing legacy addresses and helps untangle IR
devices from serial8250 devices.
Sometimes the SMC device is at a legacy COM port address but does not use the
legacy COM IRQ. In this case, claiming the device using PNP rather than 8250
legacy probe means we can automatically use the correct IRQ rather than
forcing the user to use "setserial" to set the IRQ manually.
If the PNP claim doesn't work, make sure you don't have a setserial init
script, e.g., /etc/init.d/setserial, configured to poke in legacy COM port
resources for the IRDA device. That causes the serial driver to claim
resources needed by this driver.
Based on this patch by Ville Syrjälä:
http://www.hpl.hp.com/personal/Jean_Tourrilhes/IrDA/ir260_smsc_pnp.diff
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Keith Owens <kaos@ocs.com.au> Cc: Len Brown <lenb@kernel.org> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Matthieu CASTET <castet.matthieu@free.fr> Cc: Jean Tourrilhes <jt@hpl.hp.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Ville Syrjala <syrjala@sci.fi> Cc: Russell King <rmk+serial@arm.linux.org.uk> Acked-by: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bjorn Helgaas [Tue, 8 May 2007 07:36:02 +0000 (00:36 -0700)]
smsc-ircc2: tidy up module parameter checking
To determine whether the user specified a module parameter, use some #defines
instead of checking for bare magic numbers.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Keith Owens <kaos@ocs.com.au> Cc: Len Brown <lenb@kernel.org> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Matthieu CASTET <castet.matthieu@free.fr> Cc: Jean Tourrilhes <jt@hpl.hp.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Ville Syrjala <syrjala@sci.fi> Cc: Russell King <rmk+serial@arm.linux.org.uk> Cc: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bjorn Helgaas [Tue, 8 May 2007 07:36:00 +0000 (00:36 -0700)]
PNP: workaround HP BIOS defect that leaves SMCF010 device partly enabled
Some HP/Compaq firmware reports via ACPI that the SMCF010 IR device is
enabled, but in fact, it leaves the device partly disabled.
HP nw8240 BIOS 68DTV Ver. F.0F, released 9/15/2005 is one BIOS that has this
problem.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Keith Owens <kaos@ocs.com.au> Cc: Len Brown <lenb@kernel.org> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Matthieu CASTET <castet.matthieu@free.fr> Cc: Jean Tourrilhes <jt@hpl.hp.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Ville Syrjala <syrjala@sci.fi> Cc: Russell King <rmk+serial@arm.linux.org.uk> Cc: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bjorn Helgaas [Tue, 8 May 2007 07:35:54 +0000 (00:35 -0700)]
PNP: notice whether we have PNP devices (PNPBIOS or PNPACPI)
This series converts i386 and x86_64 legacy serial ports to be platform
devices and prevents probing for them if we have PNP.
This prevents double discovery, where a device was found both by the legacy
probe and by 8250_pnp.
This also prevents the serial driver from claiming IRDA devices (unless they
have a UART PNP ID). The serial legacy probe sometimes assumed the wrong IRQ,
so the user had to use "setserial" to fix it.
Removing the need for setserial to make IRDA devices work seems good, but it
does break some things. In particular, you may need to keep setserial from
poking legacy UART stuff back in by doing something like "dpkg-reconfigure
setserial" with the "kernel" option. Otherwise, the setserial-discovered
"UART" will claim resources and prevent the IRDA driver from loading.
This patch:
If we can discover devices using PNP, we can skip some legacy probes. This
flag ("pnp_platform_devices") indicates that PNPBIOS or PNPACPI is enabled and
should tell us about builtin devices.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Keith Owens <kaos@ocs.com.au> Cc: Len Brown <lenb@kernel.org> Cc: Adam Belay <ambx1@neo.rr.com> Cc: Matthieu CASTET <castet.matthieu@free.fr> Cc: Jean Tourrilhes <jt@hpl.hp.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Ville Syrjala <syrjala@sci.fi> Cc: Russell King <rmk+serial@arm.linux.org.uk> Cc: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bernhard Walle [Tue, 8 May 2007 07:35:39 +0000 (00:35 -0700)]
Add IRQF_IRQPOLL flag on arm
Add IRQF_IRQPOLL for each timer interrupt.
Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bernhard Walle [Tue, 8 May 2007 07:35:24 +0000 (00:35 -0700)]
Add IRQF_IRQPOLL flag (common code)
irqpoll is broken on some architectures that don't use the IRQ 0 for the timer
interrupt like IA64. This patch adds a IRQF_IRQPOLL flag.
Each architecture is handled in a separate pach. As I left the irq == 0 as
condition, this should not break existing architectures that use timer_irq ==
0 and that I did't address with that patch (because I don't know).
This patch:
This patch adds a IRQF_IRQPOLL flag that the interrupt registration code could
use for the interrupt it wants to use for IRQ polling.
Because this must not be the timer interrupt, an additional flag was added
instead of re-using the IRQF_TIMER constant. Until all architectures will
have an IRQF_IRQPOLL interrupt, irq == 0 will stay as alternative as it should
not break anything.
Also, note_interrupt() is called on CPU-specific interrupts to be used as
interrupt source for IRQ polling.
Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@google.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 8 May 2007 07:35:21 +0000 (00:35 -0700)]
udf: support files larger than 1G
Make UDF work correctly for files larger than 1GB. As no extent can be
longer than (1<<30)-blocksize bytes, we have to create several extents if a
big hole is being created. As a side-effect, we now don't discard
preallocated blocks when creating a hole.
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 8 May 2007 07:35:18 +0000 (00:35 -0700)]
udf: add assertions
Add a few assertions into udf_discard_prealloc() to check that the file is
sane (mostly helps debugging further patches ;).
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 8 May 2007 07:35:16 +0000 (00:35 -0700)]
udf: use get_bh()
Make UDF use get_bh() instead of directly accessing b_count and use
brelse() instead of udf_release_data() which does just brelse()...
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 8 May 2007 07:35:14 +0000 (00:35 -0700)]
UDF: introduce struct extent_position
Introduce a structure extent_position to store a position of an extent and
the corresponding buffer_head in one place.
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 8 May 2007 07:35:13 +0000 (00:35 -0700)]
udf: use sector_t and loff_t for file offsets
Use sector_t and loff_t for file offsets in UDF filesystem. Otherwise an
overflow may occur for long files. Also make inode_bmap() return offset in
the extent in number of blocks instead of number of bytes - for most
callers this is more convenient.
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some grammatical fixups and additions to atomic.h kernel-doc content
Tweak and add content for extractable documentation in asm-i386/atomic.h.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Tue, 8 May 2007 07:35:06 +0000 (00:35 -0700)]
uml: pcap devices should get MACs from command line
Allow a pcap device to be assigned a MAC on the command line. They don't
really need one, but it is handy to be able to do when your distro assigns a
new ethernet device whenever it sees a new MAC.
Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Tue, 8 May 2007 07:35:04 +0000 (00:35 -0700)]
uml: network and pcap cleanup
Some network device cleanup.
When setup_etheraddr found a globally valid MAC being assigned to an
interface, it went ahead and used it rather than assigning a random MAC like
the other cases do. This isn't really an error like the others, but it seems
consistent to make it behave the same.
We were getting some duplicate kfree() in the error case in eth_configure
because platform_device_unregister frees buffers that the error cases
following tried to free again.
The pcap initialization routine wasn't doing the proper printk of its
information, causing a printk of the first part of that line to be
unterminated by a newline.
The pcap code had a bunch of style violations, which are now fixed.
pcap_setup wasn't returning false when it detected an unrecognized
option.
The printks in pcap_user all got UM_KERN_BLAH prepended to their
format strings.
pcap_remove now checks for a non-NULL pcap structure before it calls
pcap_close.
Signed-off-by: Jeff Dike <jdike@linux.intel.com> Acked-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Tue, 8 May 2007 07:35:02 +0000 (00:35 -0700)]
x86: create asm/cmpxchg.h
i386:
Rearrange the cmpxchg code to allow atomic.h to get it without needing to
include system.h. This kills warnings in the UML build from atomic.h about
implicit declarations of cmpxchg symbols. The i386 build presumably isn't
seeing this because a separate inclusion of system.h is covering it over.
The cmpxchg stuff is moved to asm-i386/cmpxchg.h, with an include left in
system.h for the benefit of generic code which expects cmpxchg there.
Meanwhile, atomic.h includes cmpxchg.h.
This causes no noticable damage to the i386 build.
x86_64:
Move cmpxchg into its own header. atomic.h already included system.h, so
this is changed to include cmpxchg.h.
This is purely cleanup - it's not fixing any warnings - so if the x86_64
system.h isn't considered as cleanup-worthy as i386, then this can be
dropped.
It causes no noticable damage to the x86_64 build.
uml:
The i386 and x86_64 cmpxchg patches require an asm-um/cmpxchg.h for the
UML build.
Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Tue, 8 May 2007 07:34:59 +0000 (00:34 -0700)]
Remove tas()
tas() has no users, so get rid of it.
Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: <linux-arch@vger.kernel.org> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This series extena and standardises local_t operations on each architecture,
allowing a rich set of atomic operations to be done on per-cpu data with
minimal performance impact. On architectures where there seems to be no
difference between the SMP and UP operation (same memory barriers, same
LOCKing), local.h simply includes asm-generic/local.h, which removes
duplicated code from the current kernel tree.
atomic.h: atomic_add_unless as inline. Remove system.h atomic.h circular dependency
atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
I agree (with Andi Kleen) this typeof is not needed and more error
prone. All the original atomic.h code that uses cmpxchg (which includes
the atomic_add_unless) uses defines instead of inline functions,
probably to circumvent a circular dependency between system.h and
atomic.h on powerpc (which my patch addresses). Therefore, it makes
sense to use inline functions that will provide type checking.
atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
Digging into the FRV architecture shows me that it is also affected by
such a circular dependency. Here is the diff applying this against the
rest of my atomic.h patches.
It applies over the atomic.h standardization patches.
Remove an explicit cast to an integer type for the result returned by cmpxchg.
It is not per se a problem on the i386 architecture, because sizeof(int) ==
sizeof(long), but whenever this code is cut'n'pasted to a accept passing an
atomic64_t value as parameter to cmpxchg, xchg and add_unless, having 64 bits
inputs casted to 32 bits.
atomic.h: add atomic64 cmpxchg, xchg and add_unless to alpha
This series mainly adds support for missing 64 bits cmpxchg and 64 bits atomic
add unless. Therefore, principally 64 bits architectures are targeted by
these patches. It also adds the complete list of atomic operations on the
atomic_long type.
This patch:
atomic.h: add atomic64 cmpxchg, xchg and add_unless to alpha
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch provides a debugfs knob to turn kprobes on/off
o A new file /debug/kprobes/enabled indicates if kprobes is enabled or
not (default enabled)
o Echoing 0 to this file will disarm all installed probes
o Any new probe registration when disabled will register the probe but
not arm it. A message will be printed out in such a case.
o When a value 1 is echoed to the file, all probes (including ones
registered in the intervening period) will be enabled
o Unregistration will happen irrespective of whether probes are globally
enabled or not.
o Update Documentation/kprobes.txt to reflect these changes. While there
also update the doc to make it current.
We are also looking at providing sysrq key support to tie to the disabling
feature provided by this patch.
[akpm@linux-foundation.org: Use bool like a bool!]
[akpm@linux-foundation.org: add printk facility levels]
[cornelia.huck@de.ibm.com: Add the missing arch_trampoline_kprobe() for s390] Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- consolidate duplicate code in all arch_prepare_kretprobe instances
into common code
- replace various odd helpers that use hlist_for_each_entry to get
the first elemenet of a list with either a hlist_for_each_entry_save
or an opencoded access to the first element in the caller
- inline add_rp_inst into it's only remaining caller
- use kretprobe_inst_table_head instead of opencoding it
Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marko Vrh [Tue, 8 May 2007 07:34:09 +0000 (00:34 -0700)]
rtc-cmos: make it load on PNPBIOS systems
Replace CONFIG_PNPACPI with CONFIG_PNP, so it loads on ACPI-less PNPBIOS
systems.
Signed-off-by: Marko Vrh <mvrh@freeshells.ch> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:34:07 +0000 (00:34 -0700)]
rtc: remove "RTC_ALM_SET mode" bugs
This fixes a common glitch in how RTC drivers handle two "set alarm" modes,
by getting rid of the surprising/hidden one that was rarely implemented
correctly (and which could expose nonportable hardware-specific behavior).
The glitch comes from the /dev/rtcX logic implementing the legacy
RTC_ALM_SET (limited to 24 hours, needing RTC_AIE_ON) ioctl on top of the
RTC driver call providing access to the newer RTC_WKALM_SET (without those
limitations) by initializing the day/month/year fields to be invalid ...
that second mode.
Now, since few RTC drivers check those fields, and most hardware misbehaves
when faced with invalid date fields, many RTC drivers will set bogus alarm
times on those RTC_ALM_SET code paths. (Several in-tree drivers have that
issue, and I also noticed it with code reviews on several new RTC drivers.)
This patch ensures that RTC drivers never see such invalid alarm fields, by
moving some logic out of rtc-omap into the RTC_ALM_SET code and adding an
explicit check (which will prevent the issue on other code paths).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Scott Wood <scottwood@freescale.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Tue, 8 May 2007 07:34:05 +0000 (00:34 -0700)]
revert "rtc: Add rtc_merge_alarm()"
David says "884b4aaaa242a2db8c8252796f0118164a680ab5 should be reverted. It
added an rtc_merge_alarm() call to the 2.6.20 kernel, which hasn't yet been
used by any in-tree driver; this patch obviates the need for that call, and
uses a more robust approach."
Cc: Scott Wood <scottwood@freescale.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:34:03 +0000 (00:34 -0700)]
workaround rtc-related acpi table bugs
This works around a bug seen in some RTC-related ACPI table entries, and
tweaks related diagnostics to follow the ACPI convention.
The bug prevents misleading boot-time messages: platforms affected by this
bug wrongly report they can support alarms up to one year in the future,
when in fact the longest alarm is just 24 hours. That will surprise anyone
trying to use those extended alarms.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:34:02 +0000 (00:34 -0700)]
ACPI wakeup hooks for rtc-cmos
Remove /proc/acpi/alarm file when the rtc-cmos "wakealarm" file is available.
Instead, provide hooks that rtc-cmos will use.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:34:00 +0000 (00:34 -0700)]
rtc-cmos wakeup interface
I finally got around to testing the updated wakeup event hooks for rtc-cmos,
and they follow in two patches:
- Interface update ... when a simple enable_irq_wake() doesn't suffice,
the platform data can hold suspend/resume callback hooks.
- ACPI implementation ... provides callback hooks to do ACPI magic, and
eliminate the legacy /proc/acpi/alarm file.
The interface update could go into 2.6.21, but that's not essential; they
will be NOPs on most PCs, without the ACPI stuff.
I suspect the ACPI folk may have opinions about how to merge that second
patch, and how to obsolete that legacy procfs file. I'd like to see that
merge into 2.6.22 if possible...
As for how to kick it in ... two ways:
- The appended "rtcwake" program; updated since the last time it was
posted, it deals much better with timezones and DST.
- Write the /sys/class/rtc/.../wakealarm file, then go to sleep.
For some reason RTC wake from "swsusp" stopped working on a system where
it previously worked; the alarm setting appears to get clobbered. But
on the bright side, RTC wake from "standby" worked on a system that had
never been able to resume from that state before ... IDEACPI is my guess
as to why it finally started to work. It's the old "two steps forward,
one step back" dance, I guess.
/*
* rtcwake -- enter a system sleep state until specified wakeup time.
*
* This uses cross-platform Linux interfaces to enter a system sleep state,
* and leave it no later than a specified time. It uses any RTC framework
* driver that supports standard driver model wakeup flags.
*
* This is normally used like the old "apmsleep" utility, to wake from a
* suspend state like ACPI S1 (standby) or S3 (suspend-to-RAM). Most
* platforms can implement those without analogues of BIOS, APM, or ACPI.
*
* On some systems, this can also be used like "nvram-wakeup", waking
* from states like ACPI S4 (suspend to disk). Not all systems have
* persistent media that are appropriate for such suspend modes.
*
* The best way to set the system's RTC is so that it holds the current
* time in UTC. Use the "-l" flag to tell this program that the system
* RTC uses a local timezone instead (maybe you dual-boot MS-Windows).
*/
static char *progname;
#ifdef DEBUG
#define VERSION "1.0 dev (" __DATE__ " " __TIME__ ")"
#else
#define VERSION "0.9"
#endif
static unsigned verbose;
static int rtc_is_utc = -1;
/* this process works in RTC time, except when working
* with the system clock (which always uses UTC).
*/
if (rtc_is_utc)
setenv("TZ", "UTC", 1);
tzset();
/* read rtc and system clocks "at the same time", or as
* precisely (+/- a second) as we can read them.
*/
if (ioctl(fd, RTC_RD_TIME, &rtc) < 0) {
perror("read rtc time");
return 0;
}
sys_time = time(0);
if (sys_time == (time_t)-1) {
perror("read system time");
return 0;
}
/* convert rtc_time to normal arithmetic-friendly form,
* updating tm.tm_wday as used by asctime().
*/
memset(&tm, 0, sizeof tm);
tm.tm_sec = rtc.tm_sec;
tm.tm_min = rtc.tm_min;
tm.tm_hour = rtc.tm_hour;
tm.tm_mday = rtc.tm_mday;
tm.tm_mon = rtc.tm_mon;
tm.tm_year = rtc.tm_year;
tm.tm_isdst = rtc.tm_isdst; /* stays unspecified? */
rtc_time = mktime(&tm);
/* what system power mode to use? for now handle only
* standardized mode names; eventually when systems define
* their own state names, parse /sys/power/state.
*
* "on" is used just to test the RTC alarm mechanism,
* bypassing all the wakeup-from-sleep infrastructure.
*/
case 'm':
if (strcmp(optarg, "standby") == 0
|| strcmp(optarg, "mem") == 0
|| strcmp(optarg, "disk") == 0
|| strcmp(optarg, "on") == 0
) {
suspend = optarg;
break;
}
printf("%s: unrecognized suspend state '%s'\n",
progname, optarg);
goto usage;
/* alarm time, seconds-to-sleep (relative) */
case 's':
t = atoi(optarg);
if (t < 0) {
printf("%s: illegal interval %s seconds\n",
progname, optarg);
goto usage;
}
seconds = t;
break;
/* alarm time, time_t (absolute, seconds since 1/1 1970 UTC) */
case 't':
t = atoi(optarg);
if (t < 0) {
printf("%s: illegal time_t value %s\n",
progname, optarg);
goto usage;
}
alarm = t;
break;
case 'u':
rtc_is_utc = 1;
break;
case 'v':
verbose++;
break;
case 'V':
printf("%s: version %s\n", progname, VERSION);
break;
if (!alarm && !seconds) {
printf("%s: must provide wake time\n", progname);
goto usage;
}
/* REVISIT: if /etc/adjtime exists, read it to see what
* the util-linux version of hwclock assumes.
*/
if (rtc_is_utc == -1) {
printf("%s: assuming RTC uses UTC ...\n", progname);
rtc_is_utc = 1;
}
/* this RTC must exist and (if we'll sleep) be wakeup-enabled */
fd = open(devname, O_RDONLY);
if (fd < 0) {
perror(devname);
return 1;
}
if (strcmp(suspend, "on") != 0 && !may_wakeup(devname)) {
printf("%s: %s not enabled for wakeup events\n",
progname, devname);
return 1;
}
/* relative or absolute alarm time, normalized to time_t */
if (!get_basetimes(fd))
return 1;
if (verbose)
printf("alarm %ld, sys_time %ld, rtc_time %ld, seconds %u\n",
alarm, sys_time, rtc_time, seconds);
if (alarm) {
if (alarm < sys_time) {
printf("%s: time doesn't go backward to %s",
progname, ctime(&alarm));
return 1;
}
alarm += sys_time - rtc_time;
} else
alarm = rtc_time + seconds + 1;
if (setup_alarm(fd, &alarm) < 0)
return 1;
sync();
printf("%s: wakeup from \"%s\" using %s at %s",
progname, suspend, devname,
ctime(&alarm));
fflush(stdout);
usleep(10 * 1000);
if (strcmp(suspend, "on") != 0)
suspend_system(suspend);
else {
unsigned long data;
do {
t = read(fd, &data, sizeof data);
if (t < 0) {
perror("rtc read");
break;
}
if (verbose)
printf("... %s: %03lx\n", devname, data);
} while (!(data & RTC_AF));
}
if (ioctl(fd, RTC_AIE_OFF, 0) < 0)
perror("disable rtc alarm interrupt");
close(fd);
return 0;
}
This patch:
Make rtc-cmos do the relevant magic so this RTC can wake the system from a
sleep state. That magic comes in two basic flavors:
- Straightforward: enable_irq_wake(), the way it'd work on most SOC chips;
or generally with system sleep states which don't disable core IRQ logic.
- Roundabout, using non-IRQ platform hooks. This is needed with ACPI and
one almost-clone chip which uses a special wakeup-only alarm. (That's
the RTC used on Footbridge boards, FWIW, which don't do PM in Linux.)
A separate patch implements those hooks for ACPI platforms, so that rtc_cmos
can issue system wakeup events (and its sysfs "wakealarm" attribute works on
at least some systems).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:46 +0000 (00:33 -0700)]
rtc: update to class device removal patches
Fix a goof in the revised classdev support for RTCs: make sure the /dev
node info is ready before the device is registered, not after. Otherwise
the /sys/class/rtc/rtcN/dev attribute won't be created and then udev won't
have the information it needs to create the /dev/rtcN node.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:42 +0000 (00:33 -0700)]
rtc: suspend()/resume() restores system clock
RTC class suspend/resume support, re-initializing the system clock on resume
from the clock used to initialize it at boot time.
- The reinit-on-resume is hooked to the existing RTC_HCTOSYS config
option, on the grounds that a clock good enough for init must also
be good enough for re-init.
- Inlining a version of the code used by ARM, to save and restore the
delta between a selected RTC and the current system wall-clock time.
- Removes calls to that ARM code from AT91, OMAP1, and S3C RTCs. This
means that systems using those RTCs across suspend/resume will likely
want to change their kernel configs to enable RTC_HCTOSYS.
If HCTOSYS isn't using a second RTC (with battery?), this changes the
system's initial date from Jan 1970 to the epoch this hardware uses:
1998 for AT91, 2000 for OMAP1 (assuming no split power mode), etc.
This goes on top of the patch series removing "struct class_device" usage
from the RTC framework. That's all needed for class suspend()/resume().
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-By: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:38 +0000 (00:33 -0700)]
rtc: simplified /proc/driver/rtc handling
This simplifies the RTC procfs support by removing the class_interface that
hooks it into the rtc core. If it's configured, then sysfs support is now
part of the RTC core, and is never a separate module.
It also removes the class_interface hook, now that its last remaining user is
gone. (That API is usable only with a "struct class_device".)
It's another step towards being able to remove "struct class_device".
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-By: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:33 +0000 (00:33 -0700)]
rtc: simplified rtc sysfs attribute handling
This simplifies the RTC sysfs support by removing the class_interface that
hooks it into the rtc core. If it's configured, then sysfs support is now
part of the RTC core, and is never a separate module.
It's another step towards being able to remove "struct class_device".
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-By: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:30 +0000 (00:33 -0700)]
rtc: rtc interfaces don't use class_device
This patch removes class_device from the programming interface that the RTC
framework exposes to the rest of the kernel. Now an rtc_device is passed,
which is more type-safe and streamlines all the relevant code.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-By: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Tue, 8 May 2007 07:33:27 +0000 (00:33 -0700)]
rtc: remove /sys/class/rtc-dev/*
This simplifies the /dev support by removing a superfluous class_device (the
/sys/class/rtc-dev stuff) and the class_interface that hooks it into the rtc
core. Accordingly, if it's configured then /dev support is now part of the
RTC core, and is never a separate module.
It's another step towards being able to remove "struct class_device".
[bunk@stusta.de: drivers/rtc/rtc-dev.c should #include "rtc-core.h"] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-By: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ulrich Drepper [Tue, 8 May 2007 07:33:25 +0000 (00:33 -0700)]
utimensat implementation
Implement utimensat(2) which is an extension to futimesat(2) in that it
a) supports nano-second resolution for the timestamps
b) allows to selectively ignore the atime/mtime value
c) allows to selectively use the current time for either atime or mtime
d) supports changing the atime/mtime of a symlink itself along the lines
of the BSD lutimes(3) functions
For this change the internally used do_utimes() functions was changed to
accept a timespec time value and an additional flags parameter.
Additionally the sys_utime function was changed to match compat_sys_utime
which already use do_utimes instead of duplicating the work.
Also, the completely missing futimensat() functionality is added. We have
such a function in glibc but we have to resort to using /proc/self/fd/* which
not everybody likes (chroot etc).
Test application (the syscall number will need per-arch editing):
if (st2.st_atim.tv_sec != 0 || st2.st_atim.tv_nsec != 0)
{
puts ("atim not reset to zero");
status = 1;
}
if (st2.st_mtim.tv_sec != 0 || st2.st_mtim.tv_nsec != 0)
{
puts ("mtim not reset to zero");
status = 1;
}
if (status != 0)
goto out;
if (st2.st_atim.tv_sec <= st1.st_atim.tv_sec
|| st2.st_atim.tv_sec > tv.tv_sec)
{
puts ("atim not set to NOW");
status = 1;
}
if (st2.st_mtim.tv_sec <= st1.st_mtim.tv_sec
|| st2.st_mtim.tv_sec > tv.tv_sec)
{
puts ("mtim not set to NOW");
status = 1;
}
if (st2.st_atim.tv_sec != 1 || st2.st_atim.tv_nsec != 0)
{
puts ("atim not reset to one");
status = 1;
}
if (st2.st_mtim.tv_sec != 1 || st2.st_mtim.tv_nsec != 0)
{
puts ("mtim not reset to one");
status = 1;
}
if (status == 0)
puts ("all OK");
out:
close (fd);
unlink ("ttt");
unlink ("tttsym");
Josh Triplett [Tue, 8 May 2007 07:33:22 +0000 (00:33 -0700)]
rcutorture: Remove redundant assignment to cur_ops in for loop
The for loop in rcutorture_init uses the condition
cur_ops = torture_ops[i], cur_ops
but then makes the same assignment to cur_ops inside the loop. Remove the
redundant assignment inside the loop, and remove now-unnecessary braces.
Signed-off-by: Josh Triplett <josh@kernel.org> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sched: redundant reschedule when set_user_nice() boosts a prio of a task from the "expired" array
- Make TASK_PREEMPTS_CURR(task, rq) return "true" only if the task's prio
is higher than the current's one and the task is in the "active" array.
This ensures we don't make redundant resched_task() calls when the task
is in the "expired" array (as may happen now in set_user_prio(),
rt_mutex_setprio() and pull_task() ) ;
- generalise conditions for a call to resched_task() in set_user_nice(),
rt_mutex_setprio() and sched_setscheduler()
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Cc: Con Kolivas <kernel@kolivas.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sched: optimize siblings status check logic in wake_idle()
When a logical cpu 'x' already has more than one process running, then most
likely the siblings of that cpu 'x' must be busy. Otherwise the idle
siblings would have likely(in most of the scenarios) picked up the extra
load making the load on 'x' atmost one.
Use this logic to eliminate the siblings status check and minimize the cache
misses encountered on a heavily loaded system.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Dumazet [Tue, 8 May 2007 07:32:57 +0000 (00:32 -0700)]
Speed up divides by cpu_power in scheduler
I noticed expensive divides done in try_to_wakeup() and
find_busiest_group() on a bi dual core Opteron machine (total of 4 cores),
moderatly loaded (15.000 context switch per second)
oprofile numbers :
CPU: AMD64 processors, speed 2600.05 MHz (estimated)
Counted CPU_CLK_UNHALTED events (Cycles outside of halt state) with a unit
mask of 0x00 (No unit mask) count 50000
samples % symbol name
...
613914 1.0498 try_to_wake_up
834 0.0013 :ffffffff80227ae1: div %rcx
77513 0.1191 :ffffffff80227ae4: mov %rax,%r11
Some of these divides can use the reciprocal divides we introduced some
time ago (currently used in slab AFAIK)
We can assume a load will fit in a 32bits number, because with a
SCHED_LOAD_SCALE=128 value, its still a theorical limit of 33554432
When/if we reach this limit one day, probably cpus will have a fast
hardware divide and we can zap the reciprocal divide trick.
Ingo suggested to rename cpu_power to __cpu_power to make clear it should
not be modified without changing its reciprocal value too.
I did not convert the divide in cpu_avg_load_per_task(), because tracking
nr_running changes may be not worth it ? We could use a static table of 32
reciprocal values but it would add a conditional branch and table lookup.
[akpm@linux-foundation.org: !SMP build fix] Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the process idle load balancing in the presence of dynticks. cpus for
which ticks are stopped will sleep till the next event wakes it up.
Potentially these sleeps can be for large durations and during which today,
there is no periodic idle load balancing being done.
This patch nominates an owner among the idle cpus, which does the idle load
balancing on behalf of the other idle cpus. And once all the cpus are
completely idle, then we can stop this idle load balancing too. Checks added
in fast path are minimized. Whenever there are busy cpus in the system, there
will be an owner(idle cpu) doing the system wide idle load balancing.
Open items:
1. Intelligent owner selection (like an idle core in a busy package).
2. Merge with rcu's nohz_cpu_mask?
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sched: fix idle load balancing in softirqd context
Periodic load balancing in recent kernels happen in the softirq. In
certain -rt configurations, these softirqs are handled in softirqd context.
And hence the check for idle processor was always returning busy (as
nr_running > 1).
This patch captures the idle information at the tick and passes this info
to softirq context through an element 'idle_at_tick' in rq.
[kernel@kolivas.org: Fix reverse idle at tick logic] Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Layton [Tue, 8 May 2007 07:32:31 +0000 (00:32 -0700)]
inode numbering: change libfs sb creation routines to avoid collisions with their root inodes
This patch makes it so that simple_fill_super and get_sb_pseudo assign their
root inodes to be number 1. It also fixes up a couple of callers of
simple_fill_super that were passing in files arrays that had an index at
number 1, and adds a warning for any caller that sends in such an array.
It would have been nice to have made it so that it wasn't possible to make
such a collision, but some callers need to be able to control what inode
number their entries get, so I think this is the best that can be done.
Signed-off-by: Jeff Layton <jlayton@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Layton [Tue, 8 May 2007 07:32:29 +0000 (00:32 -0700)]
inode numbering: make static counters in new_inode and iunique be 32 bits
The problems are:
- on filesystems w/o permanent inode numbers, i_ino values can be larger
than 32 bits, which can cause problems for some 32 bit userspace programs on
a 64 bit kernel. We can't do anything for filesystems that have actual
>32-bit inode numbers, but on filesystems that generate i_ino values on the
fly, we should try to have them fit in 32 bits. We could trivially fix this
by making the static counters in new_inode and iunique 32 bits, but...
- many filesystems call new_inode and assume that the i_ino values they are
given are unique. They are not guaranteed to be so, since the static
counter can wrap. This problem is exacerbated by the fix for #1.
- after allocating a new inode, some filesystems call iunique to try to get
a unique i_ino value, but they don't actually add their inodes to the
hashtable, and so they're still not guaranteed to be unique if that counter
wraps.
This patch set takes the simpler approach of simply using iunique and hashing
the inodes afterward. Christoph H. previously mentioned that he thought that
this approach may slow down lookups for filesystems that currently hash their
inodes.
The questions are:
1) how much would this slow down lookups for these filesystems?
2) is it enough to justify adding more infrastructure to avoid it?
What might be best is to start with this approach and then only move to using
IDR or some other scheme if these extra inodes in the hashtable prove to be
problematic.
I've done some cursory testing with this patch and the overhead of hashing and
unhashing the inodes with pipefs is pretty low -- just a few seconds of system
time added on to the creation and destruction of 10 million pipes (very
similar to the overhead that the IDR approach would add).
The hard thing to measure is what effect this has on other filesystems. I'm
open to ways to try and gauge this.
Again, I've only converted pipefs as an example. If this approach is
acceptable then I'll start work on patches to convert other filesystems.
With a pretty-much-worst-case microbenchmark provided by Eric Dumazet
<dada1@cosmosbay.com>:
When a 32-bit program that was not compiled with large file offsets does a
stat and gets a st_ino value back that won't fit in the 32 bit field, glibc
(correctly) generates an EOVERFLOW error. We can't do anything about fs's
with larger permanent inode numbers, but when we generate them on the fly, we
ought to try and have them fit within a 32 bit field.
This patch takes the first step toward this by making the static counters in
these two functions be 32 bits.
[jlayton@redhat.com: mention that it's only the case for 32bit, non-LFS stat] Signed-off-by: Jeff Layton <jlayton@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Nikitenko [Tue, 8 May 2007 07:32:25 +0000 (00:32 -0700)]
au1550 SPI controller driver
Here is a driver for the Alchemy au1550 PSC (Programmable Serial
Controller) in SPI master mode.
It supports dma transfers using the Alchemy descriptor based dma controller
for 4-8 bits per word SPI transfers. For 9-24 bits per word transfers, pio
irq based mode is used to avoid setup of dma channels from scratch on each
number of bits per word change.
Tested with au1550; this may also work on other MIPS Alchemy cpus, like
au1200/au1210/au1250. Used extensively with SD card connected via SPI;
this handles 8.1MHz SPI clock transfers using dma without any problem (the
highest SPI clock freq possible with au1550 running on 324MHz).
The driver supports sharing of SPI bus by multiple devices. All features
of Alchemy SPI mode are supported (all SPI modes, msb/lsb first, bits per
word in 4-24 range).
As the SPI clock of the controller depends on main input clock that shall
be configured externally, platform data structure for au1550 SPI controller
driver contains mainclk_hz attribute to define the input clock rate. From
this value, dividers of the controller for SPI clock are set up for
required frequency.
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Whitespace and section fixups. Remove partial workaround for platform
setup bug in dma_mask setup; it couldn't work with multiple controllers.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / linux-2.6 / log