Commit Graph

1719 Commits

Author SHA1 Message Date
Uwe Kleine-König
c4dba0119b i2c/i2c-omap: add a const qualifier
This prepares *of_device_id.data becoming const. Without this change
the following warning would occur:

	drivers/i2c/busses/i2c-omap.c: In function 'omap_i2c_probe':
	drivers/i2c/busses/i2c-omap.c:1025: warning: assignment discards qualifiers from pointer target type

Reviewed-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2012-09-11 08:56:47 +02:00
Linus Torvalds
3e9a97082f This patch series contains a major revamp of how we collect entropy
from interrupts for /dev/random and /dev/urandom.  The goal is to
 addresses weaknesses discussed in the paper "Mining your Ps and Qs:
 Detection of Widespread Weak Keys in Network Devices", by Nadia
 Heninger, Zakir Durumeric, Eric Wustrow, J. Alex Halderman, which will
 be published in the Proceedings of the 21st Usenix Security Symposium,
 August 2012.  (See https://factorable.net for more information and an
 extended version of the paper.)
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Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull random subsystem patches from Ted Ts'o:
 "This patch series contains a major revamp of how we collect entropy
  from interrupts for /dev/random and /dev/urandom.

  The goal is to addresses weaknesses discussed in the paper "Mining
  your Ps and Qs: Detection of Widespread Weak Keys in Network Devices",
  by Nadia Heninger, Zakir Durumeric, Eric Wustrow, J.  Alex Halderman,
  which will be published in the Proceedings of the 21st Usenix Security
  Symposium, August 2012.  (See https://factorable.net for more
  information and an extended version of the paper.)"

Fix up trivial conflicts due to nearby changes in
drivers/{mfd/ab3100-core.c, usb/gadget/omap_udc.c}

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (33 commits)
  random: mix in architectural randomness in extract_buf()
  dmi: Feed DMI table to /dev/random driver
  random: Add comment to random_initialize()
  random: final removal of IRQF_SAMPLE_RANDOM
  um: remove IRQF_SAMPLE_RANDOM which is now a no-op
  sparc/ldc: remove IRQF_SAMPLE_RANDOM which is now a no-op
  [ARM] pxa: remove IRQF_SAMPLE_RANDOM which is now a no-op
  board-palmz71: remove IRQF_SAMPLE_RANDOM which is now a no-op
  isp1301_omap: remove IRQF_SAMPLE_RANDOM which is now a no-op
  pxa25x_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op
  omap_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op
  goku_udc: remove IRQF_SAMPLE_RANDOM which was commented out
  uartlite: remove IRQF_SAMPLE_RANDOM which is now a no-op
  drivers: hv: remove IRQF_SAMPLE_RANDOM which is now a no-op
  xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-op
  n2_crypto: remove IRQF_SAMPLE_RANDOM which is now a no-op
  pda_power: remove IRQF_SAMPLE_RANDOM which is now a no-op
  i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op
  input/serio/hp_sdc.c: remove IRQF_SAMPLE_RANDOM which is now a no-op
  mfd: remove IRQF_SAMPLE_RANDOM which is now a no-op
  ...
2012-07-31 19:07:42 -07:00
Linus Torvalds
6df419e45d Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
 "This is the first part of the media patches for v3.6.

  This patch series contain:
   - new DVB frontend: rtl2832
   - new video drivers: adv7393
   - some unused files got removed
   - a selection API cleanup between V4L2 and V4L2 subdev API's
   - a major redesign at v4l-ioctl2, in order to clean it up
   - several driver fixes and improvements."

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (174 commits)
  v4l: Export v4l2-common.h in include/linux/Kbuild
  media: Revert "[media] Terratec Cinergy S2 USB HD Rev.2"
  [media] media: Use pr_info not homegrown pr_reg macro
  [media] Terratec Cinergy S2 USB HD Rev.2
  [media] v4l: Correct conflicting V4L2 subdev selection API documentation
  [media] Feature removal: V4L2 selections API target and flag definitions
  [media] v4l: Unify selection flags documentation
  [media] v4l: Unify selection flags
  [media] v4l: Common documentation for selection targets
  [media] v4l: Unify selection targets across V4L2 and V4L2 subdev interfaces
  [media] v4l: Remove "_ACTUAL" from subdev selection API target definition names
  [media] V4L: Remove "_ACTIVE" from the selection target name definitions
  [media] media: dvb-usb: print mac address via native %pM
  [media] s5p-tv: Use module_i2c_driver in sii9234_drv.c file
  [media] media: gpio-ir-recv: add allowed_protos for platform data
  [media] s5p-jpeg: Use module_platform_driver in jpeg-core.c file
  [media] saa7134: fix spelling of detach in label
  [media] cx88-blackbird: replace ioctl by unlocked_ioctl
  [media] cx88: don't use current_norm
  [media] cx88: fix a number of v4l2-compliance violations
  ...
2012-07-30 19:03:41 -07:00
Linus Torvalds
27c1ee3f92 Merge branch 'akpm' (Andrew's patch-bomb)
Merge Andrew's first set of patches:
 "Non-MM patches:

   - lots of misc bits

   - tree-wide have_clk() cleanups

   - quite a lot of printk tweaks.  I draw your attention to "printk:
     convert the format for KERN_<LEVEL> to a 2 byte pattern" which
     looks a bit scary.  But afaict it's solid.

   - backlight updates

   - lib/ feature work (notably the addition and use of memweight())

   - checkpatch updates

   - rtc updates

   - nilfs updates

   - fatfs updates (partial, still waiting for acks)

   - kdump, proc, fork, IPC, sysctl, taskstats, pps, etc

   - new fault-injection feature work"

* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  drivers/misc/lkdtm.c: fix missing allocation failure check
  lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
  fault-injection: add tool to run command with failslab or fail_page_alloc
  fault-injection: add selftests for cpu and memory hotplug
  powerpc: pSeries reconfig notifier error injection module
  memory: memory notifier error injection module
  PM: PM notifier error injection module
  cpu: rewrite cpu-notifier-error-inject module
  fault-injection: notifier error injection
  c/r: fcntl: add F_GETOWNER_UIDS option
  resource: make sure requested range is included in the root range
  include/linux/aio.h: cpp->C conversions
  fs: cachefiles: add support for large files in filesystem caching
  pps: return PTR_ERR on error in device_create
  taskstats: check nla_reserve() return
  sysctl: suppress kmemleak messages
  ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
  ipc: compat: use signed size_t types for msgsnd and msgrcv
  ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
  ipc: add COMPAT_SHMLBA support
  ...
2012-07-30 17:25:34 -07:00
Viresh Kumar
dd995c9d82 i2c/i2c-pxa: remove conditional compilation of clk code
With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

pxa i2c also has these dummy macros defined locally.  Remove them as they
aren't required anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:12 -07:00
Linus Torvalds
287dc4b764 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "More hardware support across the field including a bunch of device
  drivers.  The highlight however really are further steps towards
  device tree.

  This has been sitting in -next for ages.  All MIPS _defconfigs have
  been tested to boot or where I don't have hardware available, to at
  least build fine."

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (77 commits)
  MIPS: Loongson 1B: Add defconfig
  MIPS: Loongson 1B: Add board support
  MIPS: Netlogic: early console fix
  MIPS: Netlogic: Fix indentation of smpboot.S
  MIPS: Netlogic: remove cpu_has_dc_aliases define for XLP
  MIPS: Netlogic: Remove unused pcibios_fixups
  MIPS: Netlogic: Add XLP SoC devices in FDT
  MIPS: Netlogic: Add IRQ mappings for more devices
  MIPS: Netlogic: USB support for XLP
  MIPS: Netlogic: XLP PCIe controller support.
  MIPS: Netlogic: Platform changes for XLR/XLS I2C
  MIPS: Netlogic: Platform NAND/NOR flash support
  MIPS: Netlogic: Platform changes for XLS USB
  MIPS: Netlogic: Remove NETLOGIC_ prefix
  MIPS: Netlogic: SMP wakeup code update
  MIPS: Netlogic: Update comments in smpboot.S
  MIPS: BCM63XX: Add 96328avng reference board
  MIPS: Expose PCIe drivers for MIPS
  MIPS: BCM63XX: Add PCIe Support for BCM6328
  MIPS: BCM63XX: Move the PCI initialization into its own function
  ...
2012-07-30 11:45:52 -07:00
Linus Torvalds
a410963ba4 Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull embedded i2c changes from Wolfram Sang:
 "Changes for the "embedded" part of the I2C subsystem:

   - lots of devicetree conversions of drivers (and preparations for
     that)
   - big cleanups for drivers for OMAP, Tegra, Nomadik, Blackfin
   - Rafael's struct dev_pm_ops conversion patches for I2C
   - usual driver cleanups and fixes

  All patches have been in linux-next for an apropriate time and all
  patches touching files outside of i2c-folders should have proper acks
  from the maintainers."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (60 commits)
  Revert "i2c: tegra: convert normal suspend/resume to *_noirq"
  I2C: MV64XYZ: Add Device Tree support
  i2c: stu300: use devm managed resources
  i2c: i2c-ocores: support for 16bit and 32bit IO
  V4L/DVB: mfd: use reg_shift instead of regstep
  i2c: i2c-ocores: Use reg-shift property
  i2c: i2c-ocores: DT bindings and minor fixes.
  i2c: mv64xxxx: remove EXPERIMENTAL tag
  i2c-s3c2410: Use plain pm_runtime_put()
  i2c: s3c2410: Fix pointer type passed to of_match_node()
  i2c: mxs: Set I2C timing registers for mxs-i2c
  i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
  i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
  i2c:i2c-bfin-twi: include twi head file
  i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
  i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
  i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
  i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
  i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
  i2c-mv64xxxx: allow more than one driver instance
  ...

Conflicts:
	drivers/i2c/busses/i2c-nomadik.c
2012-07-28 13:43:12 -07:00
Wolfram Sang
5db20c49e2 Revert "i2c: tegra: convert normal suspend/resume to *_noirq"
This reverts commit 7c86d44cda.
Stephen says:

IIRC, I proposed it before solely to solve some suspend/resume ordering
issues, and Colin Cross NAKd it. These days, deferred probe should make
this change unnecessary.

Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-24 17:32:45 +02:00
Laurent Pinchart
fb604a3d58 i2c-omap: Add support for I2C_M_STOP message flag
Generate a stop condition after each message marked with I2C_M_STOP.

[JD: Add I2C_FUNC_PROTOCOL_MANGLING.]

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Laurent Pinchart
72fc2c7f78 i2c: Fall back to emulated SMBus if the operation isn't supported natively
Adapter drivers might support only a subset of the SMBus operations
natively. Those drivers currently have to manually emulate unsupported
operations using I2C.

Make the i2c_smbus_xfer() function fall back to
i2c_smbus_xfer_emulated() when the adapter's .smbus_xfer() operation
returns -EOPNOTSUPP, like it already does when the .smbus_xfer()
operation isn't available at all.

[JD: Minor optimization.]

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Laurent Pinchart
d47726c521 i2c: Add SCCB support
SCCB is a serial communication bus developed by Omnivision. Its 2-wire
mode is very similar to SMBus byte data transactions, but requires the
controller to ignore the ACK bit and to insert a stop condition after
each message.

Add a device SCCB flag and a message stop flag to be passed to
controller drivers.

[JD: Kill rogue definition in go7007 driver.]

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Emmanuel Deloget
68a7602f09 i2c-tiny-usb: Add support for the Robofuzz OSIF USB/I2C converter
Robofuzz OSIF is a generic USB/iIC interface that embeds an ATMega8A
AVR-RISC microcontroler.

The device is based upon Till Harbaum's i2c-tiny-usb and although it
enhances the original design with further functionnalities it still
maintain compatibility with it with respect to the USB/I2C interface.

Signed-off-by: Emmanuel Deloget <logout@free.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Daniel Kurtz
d3ff6ce400 i2c-i801: Enable IRQ for byte_by_byte transactions
Byte-by-byte transactions are used primarily for accessing I2C devices
with an SMBus controller.  For these transactions, for each byte that is
read or written, the SMBus controller generates a BYTE_DONE IRQ.  The isr
reads/writes the next byte, and clears the IRQ flag to start the next byte.
On the penultimate IRQ, the isr also sets the LAST_BYTE flag.

There is no locking around the cmd/len/count/data variables, since the
I2C adapter lock ensures there is never multiple simultaneous transactions
for the same device, and the driver thread never accesses these variables
while interrupts might be occurring.

The end result is faster I2C block read and write transactions.

Note: This patch has only been tested and verified by doing I2C read and
write block transfers on Cougar Point 6 Series PCH, as well as I2C read
block transfers on ICH5.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Jean Delvare
29b608540b i2c-i801: Enable interrupts on ICH5/7/8/9/10
Enable interrupts on more devices. ICH5, ICH7(-M) and ICH10 have been
tested to work OK. ICH8 and ICH9 are expected to work just fine as
they are very close to ICH7 and ICH10.

Ultimately we want to enable this feature on at least every device
since the ICH5, but for now we limit the exposure. We'll enable it for
other devices if we don't get negative feedback.

As a bonus, let the user know when interrupts are used.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Daniel Kurtz <djkurtz@chromium.org>
2012-07-24 14:13:59 +02:00
Daniel Kurtz
636752bcb5 i2c-i801: Enable IRQ for SMBus transactions
Add a new 'feature' to i2c-i801 to enable using PCI interrupts.
When the feature is enabled, then an isr is installed for the device's
PCI IRQ.

An I2C/SMBus transaction is always terminated by one of the following
interrupt sources: FAILED, BUS_ERR, DEV_ERR, or on success: INTR.

When the isr fires for one of these cases, it sets the ->status variable
and wakes up the waitq.  The waitq then saves off the status code, and
clears ->status (in preparation for some future transaction).
The SMBus controller generates an INTR irq at the end of each
transaction where INTREN was set in the HST_CNT register.

No locking is needed around accesses to priv->status since all writes to
it are serialized: it is only ever set once in the isr at the end of a
transaction, and cleared while no interrupts can occur.  In addition, the
I2C adapter lock guarantees that entire I2C transactions for a single
adapter are always serialized.

For this patch, the INTREN bit is set only for SMBus block, byte and word
transactions, but not for I2C reads or writes.  The use of the DS
(BYTE_DONE) interrupt with byte-by-byte I2C transactions is implemented in
a subsequent patch.

The interrupt feature has only been enabled for COUGARPOINT hardware.
In addition, it is disabled if SMBus is using the SMI# interrupt.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:58 +02:00
Jean Delvare
6cad93c4bb i2c-i801: Consolidate polling
(Based on earlier work by Daniel Kurtz.)

Come up with a consistent, driver-wide strategy for event polling. For
intermediate steps of byte-by-byte block transactions, check for
BYTE_DONE or any error flag being set. At the end of every transaction
(regardless of PEC being used), check for both BUSY being cleared and
INTR or any error flag being set. This ensures proper action for all
transaction types.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Daniel Kurtz <djkurtz@chromium.org>
2012-07-24 14:13:58 +02:00
Daniel Kurtz
37af871112 i2c-i801: Drop ENABLE_INT9
Later patches enable interrupts.  This preliminary patch removes the older
unsupported ENABLE_INT9 flag.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:58 +02:00
Daniel Kurtz
edbeea6383 i2c-i801: Rename some SMBHSTCNT bit constants
Rename the SMBHSTCNT register bit access constants to match the style of
other register bits.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:58 +02:00
Daniel Kurtz
70a1cc1952 i2c-i801: Check and return errors during byte-by-byte transfers
If an error is detected in the polling loop, abort the transaction and
return an error code.

 * DEV_ERR is set if the device does not respond with an acknowledge, and
the SMBus controller times out (minimum 25ms).
 * BUS_ERR is set if a bus arbitration collision is detected.  In other
words, when the SMBus controller tries to generate a START condition, but
detects that the SMBDATA is being held low, usually by another SMBus/I2C
master.
 * FAILED is only set if a transaction is stopped by software (using
the SMBHSTCNT KILL bit).

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:58 +02:00
Daniel Kurtz
0ba8b8bfd5 i2c-i801: Clear only status bits in HST_STS
Writing back the whole status register could clear unwanted bits.
In particular, it could clear the "INUSE_STS" bit, which is a
'hardware semaphore', that might be useful to use some day.
To prepare for this, let's ban writing back the whole status to register
HST_STS, of which this is the only instance.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:57 +02:00
Daniel Kurtz
efa3cb15ad i2c-i801: Refactor use of LAST_BYTE in i801_block_transaction_byte_by_byte
As a slight optimization, pull some logic out of the polling loop during
byte-by-byte transactions by just setting the I801_LAST_BYTE bit, as
defined in the i801 (PCH) datasheet, when reading the last byte of a
byte-by-byte I2C_SMBUS_READ.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:57 +02:00
Fabio Estevam
fda2f4af37 i2c-smbus: Use module_i2c_driver()
Using module_i2c_driver() makes the code smaller and cleaner.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:57 +02:00
Andrew Armenia
2a2f7404a1 i2c-piix4: Support AMD auxiliary SMBus controller
Some AMD chipsets, such as the SP5100, have an auxiliary SMBus
controller with a second set of registers. This patch adds
support for this auxiliary controller.

Tested on ASUS KCMA-D8 motherboard.

Signed-off-by: Andrew Armenia <andrew@asquaredlabs.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:57 +02:00
Andrew Armenia
e154bf6fbf i2c-piix4: Separate registration and probing code
Some chipsets have multiple sets of SMBus registers each controlling a
separate SMBus. Supporting these chipsets properly will require registering
multiple I2C adapters for one piix4.

The code to initialize and register the i2c_adapter structure has been
separated from piix4_probe and allows registration of a piix4 adapter
given its base address. Note that the i2c_adapter and i2c_piix4_adapdata
structures are now dynamically allocated.

Signed-off-by: Andrew Armenia <andrew@asquaredlabs.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:56 +02:00
Andrew Armenia
14a8086d27 i2c-piix4: Eliminate piix4_smba global variable
Some chipsets have multiple sets of piix4-compatible SMBus registers.
Eliminating the global variable will allow these chipsets to be fully
supported.

Return value from piix4_setup and piix4_sb800_setup now returns the smba
value detected. This is stored in a struct i2c_piix4_adapdata. Thus
the global variable is eliminated.

Signed-off-by: Andrew Armenia <andrew@asquaredlabs.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:56 +02:00
Axel Lin
56f2178898 i2c/busses: Use module_pci_driver
Convert the drivers in drivers/i2c/busses/* to usemodule_pci_driver()
macro which makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Rudolf Marek <r.marek@assembler.cz>
Cc: Olof Johansson <olof@lixom.net>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Cc: Tomoya MORINAGA <tomoya.rohm@gmail.com>
2012-07-24 14:13:56 +02:00
Guenter Roeck
83a638df36 i2c: Update Guenter Roeck's e-mail address
My old e-mail address won't be valid for much longer. Time to update it.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:56 +02:00
Linus Torvalds
83c7f72259 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc updates from Benjamin Herrenschmidt:
 "Notable highlights:

   - iommu improvements from Anton removing the per-iommu global lock in
     favor of dividing the DMA space into pools, each with its own lock,
     and hashed on the CPU number.  Along with making the locking more
     fine grained, this gives significant improvements in multiqueue
     networking scalability.

   - Still from Anton, we know provide a vdso based variant of getcpu
     which makes sched_getcpu with the appropriate glibc patch something
     like 18 times faster.

   - More anton goodness (he's been busy !) in other areas such as a
     faster __clear_user and copy_page on P7, various perf fixes to
     improve sampling quality, etc...

   - One more step toward removing legacy i2c interfaces by using new
     device-tree based probing of platform devices for the AOA audio
     drivers

   - A nice series of patches from Michael Neuling that helps avoiding
     confusion between register numbers and litterals in assembly code,
     trying to enforce the use of "%rN" register names in gas rather
     than plain numbers.

   - A pile of FSL updates

   - The usual bunch of small fixes, cleanups etc...

  You may spot a change to drivers/char/mem.  The patch got no comment
  or ack from outside, it's a trivial patch to allow the architecture to
  skip creating /dev/port, which we use to disable it on ppc64 that
  don't have a legacy brige.  On those, IO ports 0...64K are not mapped
  in kernel space at all, so accesses to /dev/port cause oopses (and
  yes, distros -still- ship userspace that bangs hard coded ports such
  as kbdrate)."

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (106 commits)
  powerpc/mpic: Create a revmap with enough entries for IPIs and timers
  Remove stale .rej file
  powerpc/iommu: Fix iommu pool initialization
  powerpc/eeh: Check handle_eeh_events() return value
  powerpc/85xx: Add phy nodes in SGMII mode for MPC8536/44/72DS & P2020DS
  powerpc/e500: add paravirt QEMU platform
  powerpc/mpc85xx_ds: convert to unified PCI init
  powerpc/fsl-pci: get PCI init out of board files
  powerpc/85xx: Update corenet64_smp_defconfig
  powerpc/85xx: Update corenet32_smp_defconfig
  powerpc/85xx: Rename P1021RDB-PC device trees to be consistent
  powerpc/watchdog: move booke watchdog param related code to setup-common.c
  sound/aoa: Adapt to new i2c probing scheme
  i2c/powermac: Improve detection of devices from device-tree
  powerpc: Disable /dev/port interface on systems without an ISA bridge
  of: Improve prom_update_property() function
  powerpc: Add "memory" attribute for mfmsr()
  powerpc/ftrace: Fix assembly trampoline register usage
  powerpc/hw_breakpoints: Fix incorrect pointer access
  powerpc: Put the gpr save/restore functions in their own section
  ...
2012-07-23 18:54:23 -07:00
Linus Torvalds
97e7292ab5 arm-soc: clk changes
Clock support is moving to the clk subsystem. These tegra, omap and imx
 changes are for code that is still platform specific and not (yet)
 part of that subsystem.
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Merge tag 'clk' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull arm-soc clk changes from Arnd Bergmann:
 "Clock support is moving to the clk subsystem.  These tegra, omap and
  imx changes are for code that is still platform specific and not (yet)
  part of that subsystem."

Fix up conflicts in arch/arm/mach-{imx/clk-imx51-imx53.c,omap2/Makefile}

* tag 'clk' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (23 commits)
  ARM: imx: clk-imx31: Fix clock id for rnga driver
  ARM: imx: add missing item to the list of clock event modes
  ARM: i.MX5x CSPI: Fixed clock name for CSPI
  ARM: i.MX5x clocks: Fix GPT clocks
  ARM: i.MX5x clocks: Fix parent for PWM clocks
  ARM: i.MX5x clocks: Add EPIT support
  ARM: mx27: Reenable silicon version print
  ARM: clk-imx27: Fix rtc clock id
  ARM: tegra: Provide clock for only one PWM controller
  ARM: tegra: Fix PWM clock programming
  ARM: OMAP3+: clock33xx: Add AM33XX clock tree data
  ARM: OMAP3+: clock: Move common clksel_rate & clock data to common file
  ARM: tegra: dma: rename driver name for clock to "tegra-apbdma"
  ARM: tegra: Remove second instance of uart clk
  crypto: add clk_prepare/clk_unprepare
  ASoC: tegra: add clk_prepare/clk_unprepare
  staging: nvec: add clk_prepare/clk_unprepare
  spi/tegra: add clk_prepare/clk_unprepare
  Input: tegra-kbc - add clk_prepare/clk_unprepare
  USB: ehci-tegra: add clk_prepare/clk_unprepare
  ...
2012-07-23 17:51:03 -07:00
Linus Torvalds
3645f0cd96 arm-soc: sparse IRQ conversion
The I.MX platform is getting converted to use sparse IRQs. We are doing
 this for all platforms over time, because this is one of the
 requirements for building a multiplatform kernel, and generally a good
 idea.
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Merge tag 'irq' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull arm-soc sparse IRQ conversion from Arnd Bergmann:
 "The I.MX platform is getting converted to use sparse IRQs.  We are
  doing this for all platforms over time, because this is one of the
  requirements for building a multiplatform kernel, and generally a good
  idea."

* tag 'irq' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: imx: select USE_OF
  ARM: imx: Fix build error due to missing irqs.h include
  ARM: imx: enable SPARSE_IRQ for imx platform
  ARM: fiq: change FIQ_START to a variable
  tty: serial: imx: remove the use of MXC_INTERNAL_IRQS
  ARM: imx: remove unneeded mach/irq.h inclusion
  i2c: imx: remove unneeded mach/irqs.h inclusion
  ARM: imx: add a legacy irqdomain for mx31ads
  ARM: imx: add a legacy irqdomain for 3ds_debugboard
  ARM: imx: pass gpio than irq number into mxc_expio_init
  ARM: imx: leave irq_base of wm8350_platform_data uninitialized
  dma: ipu: remove the use of ipu_platform_data
  ARM: imx: move irq_domain_add_legacy call into avic driver
  ARM: imx: move irq_domain_add_legacy call into tzic driver
  gpio/mxc: move irq_domain_add_legacy call into gpio driver
  ARM: imx: eliminate macro IRQ_GPIOx()
  ARM: imx: eliminate macro IOMUX_TO_IRQ()
  ARM: imx: eliminate macro IMX_GPIO_TO_IRQ()
2012-07-23 17:36:02 -07:00
Andrew Lunn
b61d157589 I2C: MV64XYZ: Add Device Tree support
Extends the driver to get properties from device tree. Rather than
pass the N & M factors in DT, use the more standard clock-frequency
property. Calculate N & M at run time. In order to do this, we need to
know tclk. So the driver uses clk_get() etc in order to get the clock
and clk_get_rate() to determine the tclk rate. Not all platforms
however have CLK, so some #ifdefery is needed to ensure the driver
still compiles when CLK is not available.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>

[wsa: converted some ints to u32 to match signedness]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-23 22:04:11 +02:00
David Daney
f353a218de i2c: Convert i2c-octeon.c to use device tree.
There are three parts to this:

1) Remove the definitions of OCTEON_IRQ_TWSI and OCTEON_IRQ_TWSI2.
   The interrupts are specified by the device tree and these hard
   coded irq numbers block the used of the irq lines by the irq_domain
   code.

2) Remove platform device setup code from octeon-platform.c, it is
   now unused.

3) Convert i2c-octeon.c to use device tree.  Part of this includes
   using the devm_* functions instead of the raw counterparts, thus
   simplifying error handling.  No functionality is changed.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/3939/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-07-23 13:54:53 +01:00
Theodore Ts'o
d38a0149e8 i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op
With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a
no-op; interrupt randomness is now collected unconditionally in a very
low-overhead fashion; see commit 775f4b297b.  The IRQF_SAMPLE_RANDOM
flag was scheduled to be removed in 2009 on the
feature-removal-schedule, so this patch is preparation for the final
removal of this flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Ben Dooks" <ben-linux@fluff.org>
Cc: "Wolfram Sang" <w.sang@pengutronix.de>
2012-07-19 10:38:47 -04:00
Linus Walleij
6f535b9426 i2c: stu300: use devm managed resources
Allocate memory for device state using devm_kzalloc(), get the
clock using devm_clk_get(), get the IRQ using devm_request_irq(),
request and remap memory using devm_request_and_ioremap().
All to simplify accounting and letting the kernel do the
garbage-collection.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-16 13:48:51 +02:00
Ganesan Ramalingam
7326e38ffe i2c: i2c-ocores: support for 16bit and 32bit IO
Some architectures supports only 16-bit or 32-bit read/write access to
their IO space. Add a 'reg-io-width' platform and OF parameter which
specifies the IO width to support these platforms.

reg-io-width can be specified as 1, 2 or 4, and has a default value
of 1 if it is unspecified.

Signed-off-by: Ganesan Ramalingam <ganesanr@broadcom.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-14 13:30:25 +02:00
Ganesan Ramalingam
8bb986a816 i2c: i2c-ocores: Use reg-shift property
Deprecate 'regstep' property and use the standard 'reg-shift' property
for register offset shifts. 'regstep' will still be supported as an
optional property, but will give a warning when used.

Signed-off-by: Ganesan Ramalingam <ganesanr@broadcom.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-14 13:30:24 +02:00
Jayachandran C
9ae97a8996 i2c: i2c-ocores: DT bindings and minor fixes.
Cleanups to i2c-cores, no change in logic, changes are:
* Move i2c-ocores device tree documentation from source file to
  Documentation/devicetree/bindings/i2c/i2c-ocores.txt.
* Add \n to dev_warn and dev_err messages where missing
* Minor updates to the text and formatting fixes.

Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-14 13:30:14 +02:00
Wolfram Sang
097df40312 i2c: mv64xxxx: remove EXPERIMENTAL tag
As git history indicates, the driver predates the git era and is heavily
used and worked on since. Not EXPERIMENTAL anymore.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Rodolfo Giometti <giometti@linux.it>
Cc: Florian Fainelli <ffainelli@freebox.fr>
2012-07-14 12:33:27 +02:00
Mark Brown
a86ae9ff29 i2c-s3c2410: Use plain pm_runtime_put()
There's no point in using _sync() as we don't really care if the suspend
has completed immediately.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 11:18:09 +02:00
Karol Lewandowski
b900ba4c15 i2c: s3c2410: Fix pointer type passed to of_match_node()
This commit fixes warning introduced in 27452498a ("i2c-s3c2410: Rework
device type handling"):

  drivers/i2c/busses/i2c-s3c2410.c: In function 's3c24xx_get_device_quirks':
  drivers/i2c/busses/i2c-s3c2410.c:125: warning: passing argument 1 of 'of_match_node' from incompatible pointer type
  include/linux/of.h:245: note: expected 'const struct of_device_id *' but argument is of type 'const struct of_device_id (*)[4]'

Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 10:34:09 +02:00
Marek Vasut
cd4f2d4aa7 i2c: mxs: Set I2C timing registers for mxs-i2c
This patch configures the I2C bus timing registers according
to information passed via DT. Currently, 100kHz and 400kHz
modes are supported.

The TIMING2 register value is wrong in the documentation for
i.MX28! This was found and fixed by:
  Shawn Guo <shawn.guo@linaro.org>

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 10:33:42 +02:00
Lee Jones
98582d9562 ARM: ux500: Remove unused i2c platform_data initialisation code
Now that u5500 is obsolete, u8500 is the only user of the Nomadik
i2c driver. As such there is no requirement to differentiate between
initialisation values. By the time a new SoC is released, almost all
of the ux500 platform will be DT:ed, so we can make decisions based
on the compatible property instead.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2012-07-13 09:55:44 +02:00
Sonic Zhang
90c16bbf57 i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
Depend on 1e92bf6d80

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:31 +02:00
Sonic Zhang
f88aafe513 i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
Depend on commit cf93feb3a0

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:30 +02:00
Sonic Zhang
c9d87edbcc i2c:i2c-bfin-twi: include twi head file
TWI bit mask macros are moved to twi head file.
Depend on commit 61c16b5c74

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:29 +02:00
Sonic Zhang
28a377c79a i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
Current driver was developed based on BF537 0.2 HRM. In high system load, BUFRDERR error
interrupt may be raised if XMTSERV interrupt of last TX byte is not served in time
(set RSTART bit), which breaks restart tranfer as expected.

"Buffer Read Error (BUFRDERR)" description in Blackfin HRM only applys to BF537
rev. < 0.3. In later rev. and later announced Blackfin chips, such as BF527 and
BF548, a new TWI master feature "Clock Stretching" is added into the TWI controller,
BUFRDERR interrupt is not triggered after TX FIFO is empty.

This patch sets RSTART bit at the beginning of the first transfer. The SCL and SDA
is hold till XMTSERV interrupt of last TX byte is served. Restart transfer is not broken
in high system load.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>

[wsa: fixed spaces around operators]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:04 +02:00
Sonic Zhang
2ee74eb95c i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
In order to mark I2C transfer fail when MEN bit in I2C controller is
reset unexpectedly in MCOMP interrupt, interrupt status bits XMTSERV or
RCVSERV should be checked.

Master Transfer Complete (MCOMP).
[1] The initiated master transfer has completed. In the absence of a
repeat start, the bus has been released.
[0] The completion of a transfer has not been detected.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>

[wsa: fixed spaces around operators and typo in commit message]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:36:07 +02:00
Sonic Zhang
a25733d6f6 i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
Some fault i2c device may hold the sda/scl line and cause i2c driver
wait in the BUS busy loop. The I2C framework already retry the
transfer loop before timeout. Return -EAGAIN instead of pull BUSBUSY
in the other loop.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00
Sonic Zhang
a20a64d226 i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
For transfer counts > 255 bytes i2c-bfin-twi sets the data
transfer counter DCNT to 0xFF indicating unlimited transfers.
It then uses a flag iface->manual_stop to manually issue the STOP
condition, once the required amount of bytes are received.

We found that on I2C receive operation issuing the STOP condition
together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be
constantly driven low.

This patch stops receiving operation immediately in last rx interrupt.
This patch also wakes up waiting process when transfer completes.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00
Michael Hennerich
925594e035 i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
For transfer counts > 255 bytes i2c-bfin-twi sets the data
transfer counter DCNT to 0xFF indicating unlimited transfers.
It then uses a flag iface->manual_stop to manually issue the STOP
condition, once the required amount of bytes are received.

We found that on I2C receive operation issuing the STOP condition
together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be
constantly driven low.

Temporary workaround until further investigation:
Discard the RCV FIFO before issuing the STOP condition.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00