In case a work-in-progress i2c_msg has more bytes to be written, we
need to set STATUS_WRITE_IN_PROGRESS and exit from the msg_write_idx-
searching loop. Otherwise, we will overtake the current msg_write_idx
without waiting for its transmission to be processed.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* Calculate with accurate conditional expressions from DW manuals.
* Round ic_clk by adding 0.5 as it's important at high ic_clk rate.
* Take into account "tHD;STA" issue for _HCNT calculation.
* Take into account "tf" for _LCNT calculation.
* Add "cond" and "offset" fot further correction requirements.
For _HCNT calculation, there's one issue needs to be carefully
considered; DesignWare I2C core doesn't seem to have solid strategy
to meet the tHD;STA timing spec. If you configure _HCNT based on the
tHIGH timing spec, it easily results in violation of the tHD;STA spec.
After many trials, we came to the conclusion that the tHD;STA period
is proportional to (_HCNT + 3). For the safety's sake, this should be
selected by default.
As for _LCNT calculation, DW I2C core has one characteristic behavior;
he starts counting the SCL CNTs for the LOW period of the SCL clock
(tLOW) as soon as it pulls the SCL line. At that time, he doesn't take
into account the fall time of SCL signal (tf), IOW, he starts counting
CNTs without confirming the SCL input voltage has dropped to below VIL.
This characteristics becomes a problem on some platforms where tf is
considerably long, and results in violation of the tLOW timing spec.
To make the driver configurable as much as possible for various cases,
we'd have separated arguments "tf" and "offset", and for safety default
values should be 0.3 us and 0, respectively.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We couldn't know the original intent for this variable, but at this
point it's useless.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We don't have to use "struct i2c_adapter" pointer here.
Let's use a local "struct dw_i2c_dev" pointer, instead.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We don't have to use "struct i2c_adapter" pointer here.
Let's use a local "struct dw_i2c_dev" pointer, instead.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We're strongly discouraged from using the IC_CLR_INTR register because
it clears all software-clearable interrupts asserted at the moment.
stat = readl(IC_INTR_STAT);
:
: <=== Interrupts asserted during this period will be lost
:
readl(IC_CLR_INTR);
Instead, use the separately-prepared IC_CLR_* registers.
At the same time, this patch adds all remaining interrupt definitions
available in the DesignWare I2C hardware.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This driver looks originally meant for armel machines where readw()/
writew() works perfectly fine with this hardware. But that doens't
work for big-endian systems.
This patch converts all 8/16-bit-aware usages to 32-bit variants.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Add a module parameter to override the functionality bitfield. This
lets the user disable some commands. This can be used to force a chip
driver to take different code paths.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The Intel 82801 is sometimes used on systems with a BMC connected. The
BMC can access the SMBus, resulting in lost arbitration for the 82801.
We should let i2c-core retry transactions for us in this case.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
I2C bus drivers don't have to support I2C_M_REV_DIR_ADDR. It is a
deviation from the I2C specification, which only makes sense to
implement when really needed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Superseded by tdfxfb. I2C/DDC support used to live in a separate
driver but this caused driver conflicts.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
We no longer need to write the adapter name to a temporary buffer.
We can write it directly to the i2c_adapter's name field. This is
more efficient.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Michel Daenzer <michel@daenzer.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Include the i2c_adapter in struct pmac_i2c_bus. This avoids memory
fragmentation and allows for several code cleanups.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Michel Daenzer <michel@daenzer.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Log errors when they happen, otherwise we have no idea what went
wrong.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Michel Daenzer <michel@daenzer.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
I wanted to add some error logging to the i2c-powermac driver, but
found that it was very difficult due to the way the
i2c_powermac_smbus_xfer function is organized. Refactor the code in
this function so that each low-level function is only called once.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Michel Daenzer <michel@daenzer.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
The i2c-powermac driver doesn't support arbitrary multi-message I2C
transactions, only SMBus ones. Make it clear by returning an error if
a multi-message I2C transaction is attempted. This is better than only
processing the first message, because most callers won't recover from
the short transaction. Anyone wishing to issue multi-message
transactions should use the SMBus API instead of the raw I2C API.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Michel Daenzer <michel@daenzer.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
This allows i2c-pnx to free its interrupt handler when the module
is removed or if an error occurs; using the same dev_id for both
request_irq and free_irq is desirable.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Added missing mach/i2c.h and linux/io.h header file includes
Signed-off-by: Kevin Wells <kevin.wells@nxp.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Limit minimum jiffie timeout to 2 to prevent early timeout on systems
with low tick rates
Signed-off-by: Kevin Wells <kevin.wells@nxp.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The driver always ends a read with a STOP condition which
breaks subsequent I2C reads/writes in the same transaction as
these expect to do a repeated START(ReSTART).
This will also help I2C multimaster as the bus will not be released
after the first read, but when the whole transaction ends.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The controller can't do anything else before it actually generates START/STOP.
So we check busy bit to make sure START/STOP is successfully finished.
If we don't check busy bit, START/STOP may fail on some fast CPUs.
Signed-off-by: Richard Zhao <linuxzsc@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
When an ACPI resource conflict is detected, error messages are already
printed by ACPI. There's no point in causing the driver core to print
more error messages, so return one of the error codes for which no
message is printed.
This fixes bug #14293:
http://bugzilla.kernel.org/show_bug.cgi?id=14293
Signed-off-by: Jean Delvare <khali@linux-fr.org>
We recently removed the acpi_device_uid() interface because nobody
used it. I don't think it's essential here either.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
i2c: Clearly mark ACPI drivers as such
i2c: Add driver for SMBus Control Method Interface
i2c-pnx: Correct use of request_region/request_mem_region
MAINTAINERS: Add maintainer for AT24 and PCA9564/PCA9665
i2c-piix4: Add AMD SB900 SMBus device ID
i2c/chips: Remove deprecated pcf8574 driver
i2c/chips: Remove deprecated pca9539 driver
i2c/chips: Remove deprecated pcf8575 driver
gpio/pcf857x: Copy i2c_device_id from old pcf8574 driver
i2c/scx200_acb: Provide more information on bus errors
i2c: Provide compatibility links for i2c adapters
i2c: Convert i2c adapters to bus devices
i2c: Convert i2c clients to a device type
i2c/tsl2550: Use combined SMBus transactions
i2c-taos-evm: Switch echo off to improve performance
i2c: Drop unused i2c_driver.id field
As I2C is used by PMICs also, make the busses available early via
subsys_initcall().
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The mv64xxx_i2c_intr() irq handler in drivers/i2c/busses/i2c-mv64xxx.c
is declared as returning 'int', resulting in this compile-time warning:
drivers/i2c/busses/i2c-mv64xxx.c: In function 'mv64xxx_i2c_probe':
drivers/i2c/busses/i2c-mv64xxx.c:540: warning: passing argument 2 of 'request_irq' from incompatible pointer type
Fix: correct the return type to 'irqreturn_t'.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Now that we have ACPI-based SMBus controller drivers, and we will start
telling users to use them instead of native drivers when I/O resources
conflict, I think it would be good to clearly mark ACPI drivers as such
in Kconfig.
This is exactly the same as we just did for hwmon drivers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Crane Cai <crane.cai@amd.com>
This driver supports the SMBus Control Method Interface. It needs BIOS declare
ACPI control methods which described in SMBus Control Method Interface Spec.
http://smbus.org/specs/smbus_cmi10.pdf
Signed-off-by: Crane Cai <crane.cai@amd.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
request_mem_region should be used when ioremap is used subsequently.
release_region is then correspondingly replaced by release_mem_region.
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
expression start,E;
@@
- request_region
+ request_mem_region
(start,...)
... when != request_mem_region(start,...)
when != start = E
ioremap(start,...)
@@
expression r.start;
@@
- release_region
+ release_mem_region
(start,...)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Upon a bus error, it's rather hard to guess what happened. Dumping the
address, length and status provides a lot of value for troubleshooting
issues.
Signed-off-by: Willy Tarreau <wtarreau@exceliance.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
When echo is on, we waste time reading back our orders. Switching echo
off makes performance much better: SMBus byte data transactions are 47%
faster and byte transactions are 24% faster.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
PXA I2C module is also used in Marvell PXA168 and PXA910 series.
Update the module dependancy of PXA I2C.
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
This patch modifies the SuperH Mobile I2C driver to support
Runtime PM. These changes is all that is needed for proper
Runtime PM support in this driver. Driver callbacks for
Runtime PM are empty because the device registers are always
re-initialized after pm_runtime_get_sync().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
- blk clk is enabled when an irq arrives. The clk should be enabled,
but just to make sure.
- All error bits are handled no matter state machine state
- All irq's will run complete() except for irq's that wasn't an event.
- No more looking into status registers just in case an interrupt
has happend and the irq handle wasn't executed.
- irq_disable/enable are now separete functions.
- clk settings calculation changed to round upwards instead of
downwards.
- Number of address send attempts before giving up is increased to 12
from 10 since it most times take 8 tries before getting through.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Silicon Errata 1.153 has been fixed on OMAP 3630|4430 with the use of a later
version of I2C IP block.
The errata impacts OMAP 2420|2430|3430, enable the workaround for these based
on I2C IP block revision number instead of OMAP CPU type
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
ACK any pending read/write interrupts before exiting the ISR either after
completing the operation [ARDY interrupt] or in case of an error
[NACK|AL interrupt]
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
I2C status ack for [RX]RDR and [RX]RDY could
cause race conditions of clearing the event
twice and a violation of the programing
sequence as defined in TRM This patch fixes
the same.
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
When an XRDY/XDR is hit, wait for XUDF before writing data to DATA_REG.
Otherwise some data bytes can be lost while transferring them from the
memory to the I2C interface.
Do a Busy-wait for XUDF, before writing data to DATA_REG. While waiting
if there is NACK | AL, set the appropriate error flags, ack the pending
interrupts and return from the ISR.
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Vikram pandita <vikram.pandita@ti.com>
[ben-linux@fluff.org: fixed mail format and added i2c-omap to subject]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
In case of a NACK or ARDY or AL interrupt, complete the request.
There is no need to service the RRDY/RDR or XRDY/XDR interrupts.
Refer TRM SWPU114: Figure 18-31.I2C Master Transmitter Mode, Interrupt Method,
in F/S and HS Modes
http://focus.ti.com/pdfs/wtbu/SWPU114T_PrelimFinalEPDF_06_25_2009.pdf
Signed-off-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Vikram pandita <vikram.pandita@ti.com>
[ben-linux@fluff.org: fixed mail format and added i2c-omap to subject]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
