We make sure to reinit the HW in the timeout case; then we know that
interrupts are always disabled in the sections protected by the
spinlock. Thus, we can simply remove it which is a preparation for
further refactoring. While here, rename the timeout variable to
time_left which is way more readable.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We don't need to init HW before every transfer since we know the HW
state then. HW init at probe time is enough. While here, add setting the
clock register which belongs to init HW. Also, set MDBS bit since not
setting it is prohibited according to the manual.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

wait_event_timeout returns long, not int.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

5 seconds is a very large timeout, and it is hardcoded. Use the default
timeout from 'struct adapter' which is 1 second. It can also be modified
from userspace for specific workloads via i2c-dev.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The platform_device_id is not modified by these drivers and core uses it
as const.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

After more discussion, brave users, and additional datasheet evaluation,
some API updates for the new I2C slave framework became imminent. The
slave events now get some easier to understand naming. Also, the event
handling has been simplified to only need a single call to the slave
callback when an action by the backend is required.
Reported-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The first I2C slave provider using the new generic interface.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

gcc rightfully says:

drivers/i2c/busses/i2c-rcar.c:198:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Check if the ICMSR register (masked with the ICMIER register) evaluates to 0  in
the driver's interrupt handler and return IRQ_NONE in that case, like many other
drivers do.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

rcar_i2c_prepare_msg() always returns 0, so we can make this function return
*void* and thus remove the result check in rcar_i2c_master_xfer().
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

rcar_i2c_master_xfer() needlessly compares the message pointers (using indirect
addressing) in order to detect the last I2C message, while it's enough to only
compare the message indexes.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Bits 8-31 of all registers reflect the value of bits 0-7 on reads and should be
0 on writes, according to the manuals. RCAR_IRQ_ACK_{RECV|SEND} macros have all
1's in bits 8-31, thus going against the manuals, so fix them.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This reverts commit 150b8be3.

The I2C core's per-adapter locks can't protect from IRQs, so the driver still
needs a spinlock to protect the register accesses.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Sometimes the MNR and MST interrupts happen simultaneously  (stop  automatically
follows NACK, according to the manuals) and in such case the ID_NACK flag  isn't
set since the MST interrupt handling precedes MNR and all interrupts are cleared
and disabled then, so that MNR interrupt is never noticed -- this causes NACK'ed
transfers to be falsely reported as successful. Exchanging MNR and  MST handlers
fixes this issue, however the MNR bit  somehow  gets set again even after  being
explicitly cleared, so I decided to completely suppress handling of all disabled
interrupts (which is a good thing anyway)...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This driver has been flagged to drop class based instantiation. The removal
improves boot-up time and is unneeded for embedded controllers. Users have been
warned to switch for some time now, so we can actually do the removal. Keep the
DEPRECATED flag, so the core can inform users that the behaviour finally
changed now. After another transition period, this flag can go, too.
While we are here, remove the indentation for the array setup because
such things always break after some time.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message. For example,
k.alloc and v.alloc failures use dump_stack().
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NFelipe Balbi <balbi@ti.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Make clear that the driver is GPL v2 only. Remove FSF address. Remove
filename in comment. Update copyright information.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Remove some obvious comments, remove some superfluous debug output (the
error code carries the same information), some white space fixing...
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Status register and enable register are identical regarding their
layout. Use the bit definitions for both.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i2c core has per-adapter locks, so no need to protect again.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The old macros made it harder to see what was actually happening.
Replace them with something more readable.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Setting up a read or write message is similar enough to be done in one
function. Also, move a helper function into the new function since it is
only used here.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We should always check if the bus is free, independently if it is a read
or write. It should be done before the first message, though. After
that, we ourselves keep the bus busy. Remove a 'ret' assignment which
only silenced a build warning.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Remove the seperate functions and use designated constants. As readable
but less overhead. Actually, this is even more readable since the old
function used a mix of "=" and "|=".
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Remove the seperate functions and use designated constants. As readable
but less overhead.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We use devm, so irq number is only needed during probe.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Very basic operations, just called once, can also go to the caller.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NWolfram Sang <wsa@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This hardware does not support zero length transfers. Instead, the
driver does one (random) byte transfers currently with undefined results
for the slaves. We now bail out.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

While we are here, also brush up the devicetree binding documentation.
The example was an inappropriate copy from the sh_mobile driver.
Signed-off-by: NWolfram Sang <wsa@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The response to a bus NACK is to return -ENXIO instead of the
-EREMOTEIO being currently returned by the driver.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The current i2c-rcar driver does clk_get() without a corresponding
clk_put(). Add the clk to the driver private data and then get it
with the devm functions so that it is released when the driver is
unbound.

Note, we do not call clk_prepare_enable() at this point due to the
very possible magic that is being done by the pm_runtime system
underneath the driver.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i2c-rcar driver currently prints an error message if the master_xfer
callback fails. However if the bus is being probed then lots of NAKs
will be generated, causing the output of a number of errors printed.

To solve this, disable the print if the error is not -EREMOTEIO.

An example of running i2cdetect:

10: i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- 12 i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

b720423a
(i2c: rcar: add rcar-H2 support)
added R-Car H2 support on i2c-rcar.

The R-Car I2C type is based on SoC generation
(Gen1 = E1/M1/H1, Gen2 = E2/M2/H2),
but added naming was H1/H2 instead of Gen1/Gen2.
Gen1/Gen2 is better naming on this driver.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Using the same clock for all device instances is non-portable and obtaining
clock references by an ID without using a device pointer is discouraged.
This is also not needed, because on platforms, where this driver is used,
suitable clocks are available for the I2C controllers, that are children of
the peripheral clock and just pass its rate 1-to-1 to controllers. This
patch switches the driver to obtain references to correct clocks.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>