Adds support for High Speed I2C driver found in Exynos5 and
later SoCs from Samsung.

Driver only supports Device Tree method.
Signed-off-by: NNaveen Krishna Chatradhi <ch.naveen@samsung.com>
Signed-off-by: NTaekgyun Ko <taeggyun.ko@samsung.com>
Reviewed-by: NSimon Glass <sjg@google.com>
Signed-off-by: NYuvaraj Kumar C D <yuvaraj.cd@samsung.com>
Signed-off-by: NAndrew Bresticker <abrestic@google.com>
[wsa: rebased to v3.12-rc4 (no of_i2c.h anymore)]
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>

"obj" can't be NULL here.

We already know that "pkg->package.elements" gives us a valid pointer
so the next pointer after that is also non-NULL.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Renesas ARM platforms are transitioning from single-platform to
multi-platform kernels using the new ARCH_SHMOBILE_MULTI. Make the
driver available on all ARM platforms to enable it on both ARCH_SHMOBILE
and ARCH_SHMOBILE_MULTI, and increase build testing coverage with
COMPILE_TEST.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Turn clk_enable() and clk_disable() calls into clk_prepare_enable() and
clk_disable_unprepare() to get ready for the migration to the common
clock framework.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i2c-mux driver requires that the chan_id parameter
passed to the i2c_add_mux_adapter() function is equal
to the reg value for that adapter:

for_each_child_of_node(mux_dev->of_node, child) {
	ret = of_property_read_u32(child, "reg", &reg);
	if (ret)
		continue;
	if (chan_id == reg) {
		priv->adap.dev.of_node = child;
		break;
	}
}

The i2c-mux-gpio driver uses an internal logical index
for chan_id when calling i2c_add_mux_adapter() instead
of using the reg value.

Because of this, there will problems in selecting the
right adapter when the i2c-mux-gpio's index into
mux->data.values doesn't match the reg value.

An example of such a case:

mux->data.values = { 1, 0 }

For chan_id = 0, i2c-mux will bind the adapter to the
of_node with reg = <0>, but when it will call the
select() callback with chan_id set to 0, the i2c-mux-gpio
will use it as an index into mux->data.values and it will
actually select the bus with reg = <1>.
Signed-off-by: NIonut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: NAlexander Sverdlin <alexander.sverdlin@nsn.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Some gpio chips may have get/set operations that
can sleep. gpio_set_value() only works for chips
which do not sleep, for the others we will get a
kernel warning. Using gpio_set_value_cansleep()
will work for both chips that do sleep and those
who don't.
Signed-off-by: NIonut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: NPeter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

'of_match_ptr' is defined in linux/of.h. Include it explicitly to
avoid build breakage in the future.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i.MX23 I2C controller is also capable of PIO, but needs a little harder
push to behave. The controller needs to be reset after every PIO/DMA operation
for some reason, otherwise in rare cases, the controller can hang or emit
bytes onto the bus.
Signed-off-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Analyze and rework the PIO mode operation. The PIO mode operation
was unreliable on MX28, by analyzing the bus with LA, the checks
for when data were available or were to be sent were wrong.

The PIO WRITE has to be completely reworked as it multiple problems.
The MX23 datasheet helped here, see comments in the code for details.
The problems boil down to:
- RUN bit in CTRL0 must be set after DATA register was written
- The PIO transfer must be 4 bytes long tops, otherwise use
  clock stretching.
Both of these fixes are implemented.

The PIO READ operation can only be done for up to four bytes as
we are unable to read out the data from the DATA register fast
enough.

This patch also tries to document the investigation within the
code.
Signed-off-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

It seems the PIO mode does not work, or at least not like it works
on a i.MX28. Each short transfer needs about one second (without an
error message) but does not send anything on the I2C lines.
Signed-off-by: NJuergen Beisert <jbe@pengutronix.de>
Signed-off-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The 'driver' field of the i2c_client struct is redundant. The same data can be
accessed through to_i2c_driver(client->dev.driver). The generated code for both
approaches in more or less the same.

E.g. on ARM the expression client->driver->command(...) generates

		...
		ldr     r3, [r0, #28]
		ldr     r3, [r3, #32]
		blx     r3
		...

and the expression to_i2c_driver(client->dev.driver)->command(...) generates

		...
		ldr     r3, [r0, #160]
    	ldr     r3, [r3, #-4]
    	blx     r3
		...

Other architectures will generate similar code.

All users of the 'driver' field outside of the I2C core have already been
converted. So this only leaves the core itself. This patch converts the
remaining few users in the I2C core and then removes the 'driver' field from the
i2c_client struct.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
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>

When clk_get() fails, it returns an error code, not a NULL. This patch
fixes such an error handling bug.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch adds Device Tree support to the i2c-rcar driver and respective
documentation.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is no need to repeatedly query clock frequency, where it is not
expected to change. The complete loop can also trivially be replaced with
a simple division. A further loop below the one, being simplified, could
also be replaced, but that would get more complicated.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A recent patch added even more superfluous parenthesis to those, which
already were there. Remove them again.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The 'name' attribute is needed for all i2c-dev class devices, meaning
it can be created automatically by pointing to it in the class data
structure. This simplifies the code and reduces the probability for race
conditions (the name attribute should exist by the time the device is
announced to user space).
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch adds code to initialize the DMA buffer to compensate for
possible hardware data corruption.
Signed-off-by: NJames Ralston <james.d.ralston@intel.com>
[wsa: changed to use 'sizeof']
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

According to Designware I2C spec, if I2C_DYNAMIC_TAR_UPDATE is set to 1,
the 10-bit addressing mode is controlled by IC_10BITADDR_MASTER bit of
IC_TAR register instead of IC_CON register. The IC_10BITADDR_MASTER
in IC_CON register becomes read-only copy. Since I2C_DYNAMIC_TAR_UPDATE
value can't be detected from hardware register, so we will always set the
IC_10BITADDR_MASTER bit in both IC_CON and IC_TAR register whenever 10-bit
addresing mode is requested by user application.
Signed-off-by: NChew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The driver is used on PowerPC which don't provide writel_relaxed(). This
breaks the c2k and prpmc2800 default configurations. To fix the build,
turn the calls to writel_relaxed() into writel(). The impacts for ARM
should be minimal.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some functions and variables are only used if the configuration selects
HAVE_CLK. Protect them with a corresponding #ifdef CONFIG_HAVE_CLK block
to avoid compiler warnings.
Signed-off-by: NThierry Reding <treding@nvidia.com>
[wsa: added marker to #endif]
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

commit d16933b3 "i2c: s3c2410: Move
location of clk_prepare_enable() call in probe function" refactored
clk_enable and clk_disable calls yet neglected to remove the
clk_disable_unprepare call in the module's remove().

It helps remove warnings on an arndale during unbind:

echo 12c90000.i2c > /sys/bus/platform/devices/12c90000.i2c/driver/unbind

------------[ cut here ]------------
WARNING: CPU: 0 PID: 2548 at drivers/clk/clk.c:842 clk_disable+0x18/0x24()
Modules linked in:
CPU: 0 PID: 2548 Comm: bash Not tainted 3.11.0-next-20130916-00003-gf4bddbc #6
[<c0014d48>] (unwind_backtrace+0x0/0xf8) from [<c00117d0>] (show_stack+0x10/0x14)
[<c00117d0>] (show_stack+0x10/0x14) from [<c0361be8>] (dump_stack+0x6c/0xac)
[<c0361be8>] (dump_stack+0x6c/0xac) from [<c001d864>] (warn_slowpath_common+0x64/0x88)
[<c001d864>] (warn_slowpath_common+0x64/0x88) from [<c001d8a4>] (warn_slowpath_null+0x1c/0x24)
[<c001d8a4>] (warn_slowpath_null+0x1c/0x24) from [<c02c4a64>] (clk_disable+0x18/0x24)
[<c02c4a64>] (clk_disable+0x18/0x24) from [<c028d0b0>] (s3c24xx_i2c_remove+0x28/0x70)
[<c028d0b0>] (s3c24xx_i2c_remove+0x28/0x70) from [<c0217a10>] (platform_drv_remove+0x18/0x1c)
[<c0217a10>] (platform_drv_remove+0x18/0x1c) from [<c0216358>] (__device_release_driver+0x58/0xb4)
[<c0216358>] (__device_release_driver+0x58/0xb4) from [<c02163d0>] (device_release_driver+0x1c/0x28)
[<c02163d0>] (device_release_driver+0x1c/0x28) from [<c02153c0>] (unbind_store+0x58/0x90)
[<c02153c0>] (unbind_store+0x58/0x90) from [<c0214c90>] (drv_attr_store+0x20/0x2c)
[<c0214c90>] (drv_attr_store+0x20/0x2c) from [<c01032c0>] (sysfs_write_file+0x168/0x198)
[<c01032c0>] (sysfs_write_file+0x168/0x198) from [<c00ae1c0>] (vfs_write+0xb0/0x194)
[<c00ae1c0>] (vfs_write+0xb0/0x194) from [<c00ae594>] (SyS_write+0x3c/0x70)
[<c00ae594>] (SyS_write+0x3c/0x70) from [<c000e3e0>] (ret_fast_syscall+0x0/0x30)
---[ end trace 4c9f9403066f57a6 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 2548 at drivers/clk/clk.c:751 clk_unprepare+0x14/0x1c()
Modules linked in:
CPU: 0 PID: 2548 Comm: bash Tainted: G        W    3.11.0-next-20130916-00003-gf4bddbc #6
[<c0014d48>] (unwind_backtrace+0x0/0xf8) from [<c00117d0>] (show_stack+0x10/0x14)
[<c00117d0>] (show_stack+0x10/0x14) from [<c0361be8>] (dump_stack+0x6c/0xac)
[<c0361be8>] (dump_stack+0x6c/0xac) from [<c001d864>] (warn_slowpath_common+0x64/0x88)
[<c001d864>] (warn_slowpath_common+0x64/0x88) from [<c001d8a4>] (warn_slowpath_null+0x1c/0x24)
[<c001d8a4>] (warn_slowpath_null+0x1c/0x24) from [<c02c5834>] (clk_unprepare+0x14/0x1c)
[<c02c5834>] (clk_unprepare+0x14/0x1c) from [<c028d0b8>] (s3c24xx_i2c_remove+0x30/0x70)
[<c028d0b8>] (s3c24xx_i2c_remove+0x30/0x70) from [<c0217a10>] (platform_drv_remove+0x18/0x1c)
[<c0217a10>] (platform_drv_remove+0x18/0x1c) from [<c0216358>] (__device_release_driver+0x58/0xb4)
[<c0216358>] (__device_release_driver+0x58/0xb4) from [<c02163d0>] (device_release_driver+0x1c/0x28)
[<c02163d0>] (device_release_driver+0x1c/0x28) from [<c02153c0>] (unbind_store+0x58/0x90)
[<c02153c0>] (unbind_store+0x58/0x90) from [<c0214c90>] (drv_attr_store+0x20/0x2c)
[<c0214c90>] (drv_attr_store+0x20/0x2c) from [<c01032c0>] (sysfs_write_file+0x168/0x198)
[<c01032c0>] (sysfs_write_file+0x168/0x198) from [<c00ae1c0>] (vfs_write+0xb0/0x194)
[<c00ae1c0>] (vfs_write+0xb0/0x194) from [<c00ae594>] (SyS_write+0x3c/0x70)
[<c00ae594>] (SyS_write+0x3c/0x70) from [<c000e3e0>] (ret_fast_syscall+0x0/0x30)
---[ end trace 4c9f9403066f57a7 ]---
Signed-off-by: NKim Phillips <kim.phillips@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

commit 6d4028c6 (i2c: use dev_get_platdata()) did a bad conversion
of this one case:

  drivers/i2c/busses/i2c-davinci.c: In function 'davinci_i2c_probe':
  drivers/i2c/busses/i2c-davinci.c:665:2: warning: passing argument 1 of
	'dev_get_platdata' from incompatible pointer type [enabled by default]
Reviewed-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NOlof Johansson <olof@lixom.net>

This patch modify I2C driver of rcar-H1 to usable on both rcar-H1 and rcar-H2.
Signed-off-by: NNguyen Viet Dung <nv-dung@jinso.co.jp>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

let i2c core retry 3 times as sometimes we get random noack and timeout
even when we access an existing i2c client.
Signed-off-by: NZhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

if users set I2C_M_REV_DIR_ADDR, revert the direction of address.
Signed-off-by: NZhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: NRongjun Ying <rongjun.ying@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

there is a typo before, it makes the final bitrate wrong, this patch fixes
it.
Signed-off-by: NZhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

this fixes the issue that we lost to wait the i2c reset finished.
Signed-off-by: NZhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Due to hardware ANOMALY, we need to reset I2C earlier after
we get NOACK while accessing non-existing clients, otherwise
we will get errors even we access existing clients later
Signed-off-by: NZhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some Intel LPSS I2C devices make the SDA hold time and *CNT parameters
available via SSCN (standard mode) and FMCN (fast mode) ACPI methods.

Implement support for this so that we check whether an ACPI method exists
and if it does, fill in the SDA hold time and *CNT values to the device
private structure for core to use.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The DesignWare I2C controller has high count (HCNT) and low count (LCNT)
registers for each of the I2C speed modes (standard and fast). These
registers are programmed based on the input clock speed in the driver.

The current code calculates these values based on the input clock speed and
tries hard to meet the I2C bus timing requirements. This could result
non-optimal values with regarding to the bus speed. For example on Intel
BayTrail we get bus speed of 315.41kHz which is ~20% slower than we would
expect (400kHz) in fast mode (even though the timing requirements are met).

This patch makes it possible for the platform code to pass more optimal
HCNT/LCNT values to the core driver if they are known beforehand. If these
are not set we use the calculated and more conservative values.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NShinya Kuribayashi <skuribay@pobox.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

make the MPC I2C driver get, prepare and enable the gated clock item for
register access during probe; disable and unprepare the clock upon
remove(), put is done by the devm approach; hold a reference to the
clock over the period of use

clock lookup is non-fatal in this implementation as not all platforms
may provide clock specs in their device tree, but failure to enable a
clock when specified is considered fatal
Signed-off-by: NGerhard Sittig <gsi@denx.de>
Signed-off-by: NAnatolij Gustschin <agust@denx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Fix to return a negative error code in the irq get error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
[wsa: fixed wrong exit point, too]
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Return error code in the error case, and not success.
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This follows what has already been done for the DeviceTree helpers. Move
the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update
documentation accordingly.

This also solves a problem reported by Jerry Snitselaar that we can't build
the ACPI I2C helpers as a module.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>