Commit Graph

504 Commits

Author SHA1 Message Date
Simon Glass
37b8eb37f8 samsung: i2c: Split the high-speed I2C code into a new driver
Now that driver model is used for I2C on all boards, we can split the
high-speed code into its own driver. There is virtually no common code,
and this significantly reduces confusion.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
2016-12-05 13:27:54 +01:00
Simon Glass
9a1bff69cd samsung: i2c: Drop old code from I2C driver
Now that all boards use DM_I2C we can drop the old code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
2016-12-05 13:27:41 +01:00
Jagan Teki
aec9a0f19f sunxi: Rename CONFIG_SUNXI to CONFIG_ARCH_SUNXI
CONFIG_SUNXI -> CONFIG_ARCH_SUNXI
and removed CONFIG_SUNIX from config_whitelist.txt

Cc: Simon Glass <sjg@chromium.org>
Cc: Ian Campbell <ijc@hellion.org.uk>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jagan Teki <jteki@openedev.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-10-30 11:38:04 +01:00
Tom Rini
1df182ddf7 Merge branch 'master' of git://git.denx.de/u-boot-atmel 2016-10-28 14:14:18 -04:00
Wenyou Yang
52f37333bc i2c: at91_i2c: Change error return -ENODEV to -EINVAL
Change the error return value -ENODEV from to -EINVAL for more
reasonable.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2016-10-28 18:37:14 +02:00
Wenyou Yang
2ccc07bbdc i2c: at91_i2c: Remove unnecessary clock calling
Due to the peripheral clock driver improvement, remove the
unnecessary clock calling.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2016-10-28 18:37:14 +02:00
Marek Vasut
b03380805b i2c: designware: Avoid overwriting the cmd_data register
Make sure the driver writes the cmd_data register only once per
read transfer instead of doing so potentially repeatedly.

In case the read transfer didn't finish quickly enough, the loop
in the driver code would spin fast enough to write the same value
into the cmd_data register again before re-checking whether the
transfer completed, which would cause another spurious read transfer
on the bus.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefan Roese <sr@denx.de>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Chin Liang See <clsee@altera.com>
2016-10-24 18:15:47 +02:00
Simon Glass
b02e4044ff libfdt: Bring in upstream stringlist functions
These have now landed upstream. The naming is different and in one case the
function signature has changed. Update the code to match.

This applies the following upstream commits by
Thierry Reding <treding@nvidia.com> :

   604e61e fdt: Add functions to retrieve strings
   8702bd1 fdt: Add a function to get the index of a string
   2218387 fdt: Add a function to count strings

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-10-13 13:54:10 -06:00
Simon Glass
fac3e796b9 x86: i2c: Fix cast of address to 32-bit value
This gives a build warning on 64-bit x86. Fix it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2016-10-11 11:55:33 +08:00
Moritz Fischer
6d1a718fdf cros_ec: Honor the google,remote-bus dt property
Boards where ECs that use a I2C port != 0 specify this in the
devicetree file via the google,remote-bus property.
Previously this was ignored and hardcoded to port 0.

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Heiko Schocher <hs@denx.de>
Cc: u-boot@lists.denx.de
Acked-by: Simon Glass <sjg@chromium.org>
2016-10-08 09:33:36 -04:00
Stephen Warren
fc607d9ab9 i2c: tegra: only use new clock/reset APIs
Now that the standard clock/reset APIs are available for all Tegra SoCs,
convert the I2C driver to use them exclusively, and remove any references
to the custom Tegra-specific APIs.

Cc: Heiko Schocher <hs@denx.de>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-09-27 09:11:03 -07:00
Stefan Roese
87de0eb31c i2c: mvtwsi.c: Add support for Marvell Armada 7K/8K
By adding the "marvell,mv78230-i2c" compatible property, we can enable
this I2C driver to support these new ARM64 chips as well.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Neta Zur Hershkovits <neta@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Omri Itach <omrii@marvell.com>
Cc: Igal Liberman <igall@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:43:10 +02:00
jinghua
85f03f0ea8 i2c: mv_i2c.c: Validate read length in I2C command
The I2C bus will get stuck when reading 0 byte. So we add validation of
the read length in i2c_read(). This issue only occurs on read operation.

Signed-off-by: jinghua <jinghua@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:42:56 +02:00
Stefan Roese
9ad5a00712 i2c: mv_i2c.c: Enable runtime speed selection (standard vs fast mode)
This patch adds runtime speed configuration to the mv_i2c driver.
Currently standard (max 100kHz) and fast mode (max 400kHz) are
supported.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:42:37 +02:00
Stefan Roese
0c0f719ad2 i2c: mv_i2c.c: Add DM support
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:41:59 +02:00
Stefan Roese
7b46ee521e i2c: mv_i2c.c: Prepare driver for DM conversion
To prepare for the DM conversion, we add a layer of compatibility
functions to be used by both the legacy and the DM functions.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:41:17 +02:00
Stefan Roese
340fcd66cc i2c: mv_i2c.c: Remove CONFIG_HARD_I2C
CONFIG_HARD_I2C is not needed, lets remove it.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:41:03 +02:00
Stefan Roese
8eff909a56 i2c: mv_i2c.c: cosmetic: Coding style cleanups
Some mostly indentation coding style cleanups. Also, move this driver
to use debug() for debug output.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Wilson Ding <dingwei@marvell.com>
Cc: Victor Gu <xigu@marvell.com>
Cc: Hua Jing <jinghua@marvell.com>
Cc: Terry Zhou <bjzhou@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
2016-09-26 10:40:41 +02:00
Masahiro Yamada
1221ce459d treewide: replace #include <asm/errno.h> with <linux/errno.h>
Now, arch/${ARCH}/include/asm/errno.h and include/linux/errno.h have
the same content.  (both just wrap <asm-generic/errno.h>)

Replace all include directives for <asm/errno.h> with <linux/errno.h>.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[trini: Fixup include/clk.]
Signed-off-by: Tom Rini <trini@konsulko.com>
2016-09-23 17:55:42 -04:00
Wenyou Yang
76062b9cdb i2c: at91_i2c: Fix the wrong include file
Since the 'clk_client.h' doesn't exist, it should be 'clk.h'.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-09-13 06:58:54 +02:00
John Keeping
21d4b7d4e1 rockchip: i2c: fix >32 byte writes
The special handling of the chip address and register address must only
happen before we send the data buffer, otherwise we will end up
inserting both of these every 32 bytes.

Signed-off-by: John Keeping <john@metanate.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-09-13 06:57:27 +02:00
John Keeping
551288bd8b rockchip: i2c: move register write out of inner loop
There is no point in writing intermediate values to the txdata
registers.

Also add padding to the debug logging to make it easier to read when
there are leading zeroes.

Signed-off-by: John Keeping <john@metanate.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-09-13 06:57:16 +02:00
John Keeping
80333fd85c rockchip: i2c: use named constant when appropriate
Make it clear that we are using the same value in two adjacent lines.

Signed-off-by: John Keeping <john@metanate.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-09-13 06:57:05 +02:00
Tom Rini
da968c7bfa Merge branch 'master' of git://git.denx.de/u-boot-i2c 2016-08-26 07:42:06 -04:00
Stefan Roese
03d6cd972e i2c: mvtwsi: Fix order of address bytes (high to low)
Patch f8a10ed1 [i2c: mvtwsi: Make address length variable] accidentally
inverted the sequence of address bytes sent to the I2C device. This
patch corrects this by sending the highest byte first and the lowest
byte last again.

Tested on theadorable Armada-XP board.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Mario Six <mario.six@gdsys.cc>
Cc: Heiko Schocher <hs@denx.de>
2016-08-26 07:02:49 +02:00
Stephen Warren
6002c75c59 ARM: tegra: remove stale nvidia, bpmp I2C DT property
The nvidia,bpmp property is left over from an old BPMP I2C binding, and
shouldn't be present. Remove it from the SoC DT file, and update the
I2C driver not to parse it; the value wasn't used for anything any more
anyway.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-08-25 13:48:11 -07:00
Stephen Warren
b4ee081e5a ARM: tegra: fix Tegra186 I2C clock name
The Tegra I2C binding dictates that the clock name for the Tegra I2C clock
be "div-clk" not "i2c". Fix the Tegra186 DT and I2C driver to honor this.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-08-25 13:47:49 -07:00
Stefan Roese
ca6c5e03f1 i2c: intel_i2c: SMBus driver PCI addition (e.g. BayTrail)
This patch adds support for the SMBus block read/write functionality.
Other protocols like the SMBus quick command need to get added
if this is needed.

This patch also removed the SMBus related defines from the Ivybridge
pch.h header. As they are integrated in this driver and should be
used from here. This change is added in this patch to avoid compile
breakage to keep the source git bisectable.

Tested on a congatec BayTrail board to configure the SMSC2513 USB
hub.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Heiko Schocher <hs@denx.de>
Cc: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-08-16 11:44:09 +08:00
Tom Rini
0fcb9f07a1 Merge branch 'master' of git://git.denx.de/u-boot-atmel 2016-08-15 17:31:23 -04:00
Songjun Wu
8800e0fa20 i2c: atmel: add i2c driver
Add i2c driver.

Signed-off-by: Songjun Wu <songjun.wu@atmel.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>
2016-08-15 22:12:00 +02:00
Bryan Wu
3c27fa2193 i2c: tegra: add standardized clk/reset API support
clk/reset API was tested on T186 platform and previous chip like
T210/T124 will still use the old APIs.

Signed-off-by: Bryan Wu <pengw@nvidia.com>
(swarren, simplified some ifdefs, removed indent level inside an ifdef)
(swarren, added comment about the ifdefs)
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-08-15 10:26:13 -07:00
Stephen Warren
34f1c9fe14 i2c: add Tegra186 BPMP driver
On Tegra186, some I2C controllers are directly controlled by the main CPU,
whereas others are controlled by the BPMP, and can only be accessed by the
main CPU via IPC requests to the BPMP. This driver covers the latter case.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-08-15 10:26:13 -07:00
Tom Rini
f4b0df1823 Merge git://git.denx.de/u-boot-dm 2016-08-12 16:00:50 -04:00
Stephen Warren
6e06acb732 fdt: allow fdtdec_get_addr_size_*() to translate addresses
Some code may want to read reg values from DT, but from nodes that aren't
associated with DM devices, so using dev_get_addr_index() isn't
appropriate. In this case, fdtdec_get_addr_size_*() are the functions to
use. However, "translation" (via the chain of ranges properties in parent
nodes) may still be desirable. Add a function parameter to request that,
and implement it. Update all call sites to default to the original
behaviour.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Squashed in build fix from Stephen:
Signed-off-by: Simon Glass <sjg@chromium.org>
2016-08-12 09:20:27 -06:00
Simon Glass
2651a052d8 i2c: Drop redundant platform data setting in drivers
The i2c uclass has a default setting for per_child_platdata_auto_alloc_size
so drivers do not need to set it. Remove this from drivers to avoid
confusion.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2016-08-12 06:41:41 +02:00
Vignesh R
95def3cf5d i2c: i2c-uclass-compat: avoid any BSS usage
As I2C can be used before DRAM initialization for reading EEPROM,
avoid using static variables stored in BSS, since BSS is in DRAM, which
may not have been initialised yet. Explicitly mark "static global"
variables as belonging to the .data section.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Heiko Schocher<hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-08-08 13:33:00 -04:00
Simon Glass
911954859d dm: Use dm_scan_fdt_dev() directly where possible
Quite a few places have a bind() method which just calls dm_scan_fdt_dev().
We may as well call dm_scan_fdt_dev() directly. Update the code to do this.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-07-27 14:15:54 -06:00
Simon Glass
2e3f1ff63f dm: Convert users from dm_scan_fdt_node() to dm_scan_fdt_dev()
This new function is more convenient for callers, and handles pre-relocation
situations automatically.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-07-27 14:15:07 -06:00
Tom Rini
9c7a0a600b Merge git://git.denx.de/u-boot-fsl-qoriq 2016-07-26 17:34:28 -04:00
mario.six@gdsys.cc
27059c3e4d i2c: fsl: Fix driver initialization
Due to a oversight in testing, the initialization of the recently
introduced Freescale I2C DM driver works only for 36 bit mode of e.g.
the MPC85XX SoCs (specifically, if the physical addresses are 64 bit
wide and the DT addresses 32 bit wide).

This patch corrects the initialization so that it will work in a more
general setting.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: York Sun <york.sun@nxp.com>
2016-07-26 09:00:44 -07:00
mario.six@gdsys.cc
6e677caf8c i2c: mvtwsi: Add documentation
Add full documentation to all driver functions.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:20:38 +02:00
mario.six@gdsys.cc
c68c624320 i2c: mvtwsi: Make delay times frequency-dependent
Some devices using the MVTWSI driver have the option to run at speeds
faster than Standard Mode (100kHZ). On the Armada 38x controllers, this
is actually necessary, since due to erratum FE-8471889, a timing
violation concerning repeated starts prevents the controller from
working correctly in Standard Mode. One of the workarounds recommended
in the erratum is to set the bus to Fast Mode (400kHZ) operation and
ensure all connected devices are set to Fast Mode.

In the current version of the driver, however, the delay times are
hard-coded to 10ms, corresponding to Standard Mode operation. To take
full advantage of the faster modes, we would need to either keep the
currently configured I2C speed in a globally accessible variable, or
pass it to the necessary functions as a parameter. For DM, the first
option is not a problem, and we can simply keep the speed in the private
data of the driver. For the legacy interface, however, we would need to
introduce a static variable, which would cause problems with boots from
NOR flashes; see commit d6b7757 "i2c: mvtwsi: Eliminate
twsi_control_flags."

As to not clutter the interface with yet another parameter, we therefore
keep the default 10ms delays for the legacy functions.

In DM mode, we make the delay time dependant on the frequency to allow
taking full advantage of faster modes of operation (tested with up to
1MHZ frequency on Armada MV88F6820).

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:20:28 +02:00
mario.six@gdsys.cc
24f9c6bbc7 i2c: mvtwsi: Handle zero-length offsets properly
Zero-length offsets are not properly handled by the driver. When a read
operation with a zero-length offset is started, a START condition is
asserted, and since no offset bytes are transferred, a repeated START is
issued immediately after, which confuses the controller.

To fix this, we send the first START only if any address bytes need to
be sent, and keep track of the expected start status accordingly.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:20:19 +02:00
mario.six@gdsys.cc
14a6ff2c4f i2c: mvtwsi: Add compatibility to DM
This patch adds the necessary functions and Kconfig entry to make the
MVTWSI I2C driver compatible with the driver model.

A possible device tree entry might look like this:

i2c@11100 {
	compatible = "marvell,mv64xxx-i2c";
	reg = <0x11000 0x20>;
	clock-frequency = <100000>;
	u-boot,i2c-slave-addr = <0x0>;
};

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:20:13 +02:00
mario.six@gdsys.cc
f8a10ed1fd i2c: mvtwsi: Make address length variable
The length of the address parameter of the __twsi_i2c_read and
__twsi_i2c_write functions is fixed to four bytes.

As a final step in the preparation of the DM conversion, we make the
length of this parameter variable by turning it into an array of bytes,
and convert the 32 bit value that's passed to the legacy functions into
a four-byte-array on the fly.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:20:05 +02:00
mario.six@gdsys.cc
3c4db636ac i2c: mvtwsi: Factor out adap parameter
To be able to use the compatibility layer from the DM functions, we
factor the adap parameter out of all functions, and pass the actual
register base instead.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:19:56 +02:00
mario.six@gdsys.cc
61bc02b260 i2c: mvtwsi: Add compatibility functions
To prepare for the DM conversion, we add a layer of compatibility
functions to be used by both the legacy and the DM functions.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:19:49 +02:00
mario.six@gdsys.cc
e075828128 i2c: mvtwsi: Use 'uint' instead of 'unsigned int'
Since some additional parameters will be added in the course of this
patch series (especially with the addition of DM support), we replace
the longer "unsigned int" declarations with "uint" declarations to keep
the parameter lists more readable.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:19:42 +02:00
mario.six@gdsys.cc
059fce9f61 i2c: mvtwsi: Get rid of status parameter
The twsi_stop function contains a parameter "status," which is used to
pass in the current exit status of the function calling twsi_stop, and
either return this status unchanged if it indicates an error, or return
twsi_stop's exit status if it does not indicate an error.

While not massively complicated, this adds another purpose to the
twsi_stop function, which should have the sole purpose of asserting a
STOP condition on the bus (and not manage the exit status of its
caller).

Therefore, we move the exit status management into the caller functions
by introducing a "stop_status" variable and returning either the status
before the twsi_stop call (kept in the "status" variable), or the status
from the twsi_stop call, depending on which indicates an error.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:19:35 +02:00
mario.six@gdsys.cc
670514f524 i2c: mvtwsi: Eliminate flags parameter
Due to breaking boots from NOR flashes, commit d6b7757 ("i2c: mvtwsi:
Eliminate twsi_control_flags") removed the static global
twsi_control_flags variable, which kept a set of default flags that were
always or'd to the control register when writing. It was replaced with a
flags parameter, which was passed around between the functions that
needed it.

Since the twsi_control_flags variable was used just for the purposes of
a) setting the MVTWSI_CONTROL_TWSIEN on every control register write,
   and
b) setting the MVTWSI_CONTROL_ACK from twsi_i2c_read if needed,
anyway, the added overhead of another variable being passed around is no
longer justified, and we are better off implementing this flag setting
logic locally in the functions that actually write to the control
register.

Therefore, this patch sets MVTWSI_CONTROL_TWSIEN on every control
register write, replaces the twsi_i2c_read's flags parameter with a
ack_flag parameter, which tells the function whether to acknowledge the
read or not, and removes every other instance of the flags variable.
This has the added benefit that now every notion of "global default
flags" is gone, and it's much easier to see which control flags are
actually set at which point in time.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-26 10:19:29 +02:00