When there was no other way to match a I2C device to driver i2c_match_id()
was exclusively used. However, now there are other types of tables which
are commonly supplied, matching on an i2c_device_id table is used less
frequently. Instead of _always_ calling i2c_match_id() from within the
framework, we only need to do so from drivers which have no other way of
matching. This patch makes i2c_match_id() available to the aforementioned
device drivers.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently the I2C framework insists on devices supplying an I2C ID
table. Many of the devices which do so unnecessarily adding quite a
few wasted lines to kernel code. This patch allows drivers a means
to 'not' supply the aforementioned table and match on DT match tables
instead.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This function provides a single call for all I2C devices which need to
match firstly using traditional OF means i.e by of_node, then if that
fails we attempt to match using the supplied I2C client name with a
list of supplied compatible strings with the '<vendor>,' string
removed. The latter is required due to the unruly naming conventions
used currently by I2C devices.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Kieran: Fix static inline usage on !CONFIG_OF]
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
A great deal of I2C devices are currently matched via DT node name, and
as such the compatible naming convention of '<vendor>,<device>' has gone
somewhat awry - some nodes don't supply one, some supply an arbitrary
string and others the correct device name with an arbitrary vendor prefix.
In an effort to correct this problem we have to supply a mechanism to
match a device by compatible string AND by simple device name. This
function strips off the '<vendor>,' part of a supplied compatible string
and attempts to match without it.
It is also used for sysfs, where a user can choose to instantiate a
device on an i2c bus using the sysfs interface by providing a string and
address to match and communicate with the device on the bus. Presently
this string is only matched against the old i2c device id style strings,
even in the presence of full device tree compatible strings with vendor
prefixes.
Providing a vendor-prefixed string to the sysfs interface will not match
against the device tree of_match_device() calls as there is no device
tree node to parse from the sysfs interface.
This function can match both vendor prefixed and stripped compatible
strings on the sysfs interface.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Here we're providing dereference protection for i2c_match_id(), which
saves us having to do it each time it's called. We're also stripping
out the (now) needless checks in i2c_device_match(). This patch paves
the way for other, similar code trimming.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Support a dynamic clock by reading the frequency and setting the
divisor in the transfer function instead of during probe.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use i2c_adapter->timeout for the completion timeout value. The core
default is 1 second.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Documentation/i2c/i2c-protocol states that Combined transactions should
separate messages with a Start bit and end the whole transaction with a
Stop bit. This patch adds support for issuing only a Start between
messages instead of a Stop followed by a Start.
This implementation differs from downstream i2c-bcm2708 in 2 respects:
- it uses an interrupt to detect that the transfer is active instead
of using polling. There is no interrupt for Transfer Active, but by
not prefilling the FIFO it's possible to use the TXW interrupt.
- when resetting/disabling the controller between transfers it writes
CLEAR to the control register instead of just zero.
Using just zero gave many errors. This might be the reason why
downstream had to disable this feature and make it available with a
module parameter.
I have run thousands of transfers to a DS1307 (rtc), MMA8451 (accel)
and AT24C32 (eeprom) in parallel without problems.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The controller can't support this flag, so remove it.
Documentation/i2c/i2c-protocol states that all of the message is sent:
I2C_M_IGNORE_NAK:
Normally message is interrupted immediately if there is [NA] from the
client. Setting this flag treats any [NA] as [A], and all of
message is sent.
>From the BCM2835 ARM Peripherals datasheet:
The ERR field is set when the slave fails to acknowledge either
its address or a data byte written to it.
So when the controller doesn't receive an ack, it sets ERR and raises
an interrupt. In other words, the whole message is not sent.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Writing to an AT24C32 generates on average 2x i2c transfer errors per
32-byte page write. Which amounts to a lot for a 4k write. This is due
to the fact that the chip doesn't respond during it's internal write
cycle when the at24 driver tries and retries the next write.
Only a handful drivers use dev_err() on transfer error, so switch to
dev_dbg() instead.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If an unexpected TXW or RXR interrupt occurs (msg_buf_remaining == 0),
the driver has no way to fill/drain the FIFO to stop the interrupts.
In this case the controller has to be disabled and the transfer
completed to avoid hang.
(CLKT | ERR) and DONE interrupts are completed in their own paths, and
the controller is disabled in the transfer function after completion.
Unite the code paths and do disabling inside the interrupt routine.
Clear interrupt status bits in the united completion path instead of
trying to do it on every interrupt which isn't necessary.
Only CLKT, ERR and DONE can be cleared that way.
Add the status value to the error value in case of TXW/RXR errors to
distinguish them from the other S_LEN error.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Writing messages larger than the FIFO size results in a hang, rendering
the machine unusable. This is because the RXD status flag is set on the
first interrupt which results in bcm2835_drain_rxfifo() stealing bytes
from the buffer. The controller continues to trigger interrupts waiting
for the missing bytes, but bcm2835_fill_txfifo() has none to give.
In this situation wait_for_completion_timeout() apparently is unable to
stop the madness.
The BCM2835 ARM Peripherals datasheet has this to say about the flags:
TXD: is set when the FIFO has space for at least one byte of data.
RXD: is set when the FIFO contains at least one byte of data.
TXW: is set during a write transfer and the FIFO is less than full.
RXR: is set during a read transfer and the FIFO is or more full.
Implementing the logic from the downstream i2c-bcm2708 driver solved
the hang problem.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c fix from Wolfram Sang:
"A bugfix for the I2C core fixing a (rare) race condition"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: core: fix NULL pointer dereference under race condition
Pull stack vmap fixups from Thomas Gleixner:
"Two small patches related to sched_show_task():
- make sure to hold a reference on the task stack while accessing it
- remove the thread_saved_pc printout
.. and add a sanity check into release_task_stack() to catch problems
with task stack references"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Remove pointless printout in sched_show_task()
sched/core: Fix oops in sched_show_task()
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
fork: Add task stack refcounting sanity check and prevent premature task stack freeing
Pull MD fixes from Shaohua Li:
"There are several bug fixes queued:
- fix raid5-cache recovery bugs
- fix discard IO error handling for raid1/10
- fix array sync writes bogus position to superblock
- fix IO error handling for raid array with external metadata"
* tag 'md/4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md: be careful not lot leak internal curr_resync value into metadata. -- (all)
raid1: handle read error also in readonly mode
raid5-cache: correct condition for empty metadata write
md: report 'write_pending' state when array in sync
md/raid5: write an empty meta-block when creating log super-block
md/raid5: initialize next_checkpoint field before use
RAID10: ignore discard error
RAID1: ignore discard error
Pull SCSI fixes from James Bottomley:
"Two more important data integrity fixes related to RAID device drivers
which wrongly throw away the SYNCHRONIZE CACHE command in the non-RAID
path and a memory leak in the scsi_debug driver"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: arcmsr: Send SYNCHRONIZE_CACHE command to firmware
scsi: scsi_debug: Fix memory leak if LBP enabled and module is unloaded
scsi: megaraid_sas: Fix data integrity failure for JBOD (passthrough) devices
Pull FireWire (IEEE 1394) fixes from Stefan Richter:
- add missing input validation to the firewire-net driver. Invalid
IP-over-1394 encapsulation headers could trigger buffer overflows
(CVE 2016-8633).
- IP-over-1394 link fragmentation headers were read and written
incorrectly, breaking fragmented RX/TX with other OS's stacks.
* tag 'firewire-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: net: fix fragmented datagram_size off-by-one
firewire: net: guard against rx buffer overflows
Pull media fixes from Mauro Carvalho Chehab:
"A series of fixup patches meant to fix the usage of DMA on stack, plus
one warning fixup"
* tag 'media/v4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (32 commits)
[media] radio-bcm2048: don't ignore errors
[media] pctv452e: fix semicolon.cocci warnings
[media] flexcop-usb: don't use stack for DMA
[media] stk-webcam: don't use stack for DMA
[media] s2255drv: don't use stack for DMA
[media] cpia2_usb: don't use stack for DMA
[media] digitv: handle error code on RC query
[media] dw2102: return error if su3000_power_ctrl() fails
[media] nova-t-usb2: handle error code on RC query
[media] technisat-usb2: use DMA buffers for I2C transfers
[media] pctv452e: don't call BUG_ON() on non-fatal error
[media] pctv452e: don't do DMA on stack
[media] nova-t-usb2: don't do DMA on stack
[media] gp8psk: don't go past the buffer size
[media] gp8psk: don't do DMA on stack
[media] dtv5100: don't do DMA on stack
[media] dtt200u: handle USB control message errors
[media] dtt200u: don't do DMA on stack
[media] dtt200u-fe: handle errors on USB control messages
[media] dtt200u-fe: don't do DMA on stack
...
Pull PCI fixes from Bjorn Helgaas:
- fix for a Qualcomm driver issue that causes a use-before-set crash
- fix for DesignWare iATU unroll support that causes external aborts
when enabling the host bridge
* tag 'pci-v4.9-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: designware: Check for iATU unroll support after initializing host
PCI: qcom: Fix pp->dev usage before assignment
Pull MTD fixes from Brian Norris:
- MAINTAINERS updates to reflect some new maintainers/submaintainers.
We have some great volunteers who've been developing and reviewing
already. We're going to try a group maintainership model, so
eventually you'll probably see pull requests from people besides me.
- NAND fixes from Boris:
"Three simple fixes:
- fix a non-critical bug in the gpmi driver
- fix a bug in the 'automatic NAND timings selection' feature
introduced in 4.9-rc1
- fix a false positive uninitialized-var warning"
* tag 'for-linus-20161104' of git://git.infradead.org/linux-mtd:
mtd: mtk: avoid warning in mtk_ecc_encode
mtd: nand: Fix data interface configuration logic
mtd: nand: gpmi: disable the clocks on errors
MAINTAINERS: add more people to the MTD maintainer team
MAINTAINERS: add a maintainer for the SPI NOR subsystem
Pull GPIO fixes from Linus Walleij:
"Some GPIO fixes for the v4.9 series:
- Fix a nasty file descriptor leak when getting line handles.
- A fix for a cleanup that seemed innocent but created a problem for
drivers instantiating several gpiochips for one single OF node.
- Fix a unpredictable problem using irq_domain_simple() in the mvebu
driver by converting it to a lineas irqdomain"
* tag 'gpio-v4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio/mvebu: Use irq_domain_add_linear
gpio: of: fix GPIO drivers with multiple gpio_chip for a single node
gpio: GPIO_GET_LINE{HANDLE,EVENT}_IOCTL: Fix file descriptor leak
Pull nfsd bugfixes from Bruce Fields:
"Fixes for some recent regressions including fallout from the vmalloc'd
stack change (after which we can no longer encrypt stuff on the
stack)"
* tag 'nfsd-4.9-1' of git://linux-nfs.org/~bfields/linux:
nfsd: Fix general protection fault in release_lock_stateid()
svcrdma: backchannel cannot share a page for send and rcv buffers
sunrpc: fix some missing rq_rbuffer assignments
sunrpc: don't pass on-stack memory to sg_set_buf
nfsd: move blocked lock handling under a dedicated spinlock