Commit Graph

561252 Commits

Author SHA1 Message Date
Paul Gortmaker
c698d639f7 i2c: create builtin_i2c_driver to avoid registration boilerplate
In commit f309d44431 ("platform_device:
better support builtin boilerplate avoidance") we introduced the
builtin_driver macro.

Here we use that support and extend it to I2C driver registration,
so where a driver is clearly non-modular and builtin-only, we can
register it in a similar fashion.  And existing code that is clearly
non-modular can be updated with the simple mapping of

     module_i2c_driver(...)  ---> builtin_i2c_driver(...)

We've essentially cloned the former to make the latter, and taken
out the remove/module_exit parts since those never get used in a
non-modular build of the code.

A similar thing was done in commit b4eb6cdbbd
("PCI: Add builtin_pci_driver() to avoid registration boilerplate").

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-13 11:06:03 +01:00
Gao Pan
c552815312 i2c: imx: fix i2c resource leak with dma transfer
In i2c_imx_dma_xfer(), when dmaengine_submit() returns error,
the context goto label err_submit and then return. However, the
memory allocated for txdesc has not been freed yet, which
leads to resource leak.

Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 10:10:28 +01:00
Wolfram Sang
a570a27af4 dt-bindings: i2c: eeprom: add another EEPROM device
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:39:39 +01:00
Wolfram Sang
f5e12d0d5b dt-bindings: move I2C eeprom descriptions to the proper file
EEPROMs can have additional properties, so they are not suitable for
trivial-devices.txt. Move most bindings to the designated eeprom.txt.
Add the missing "atmel,24c08" while doing that. Note that the remaining
ones in trivial-devices need to be dealt with separately because of
improper manufacturer names.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:39:12 +01:00
Suravee Suthikulpanit
b33af11de2 i2c: designware: Do not require clock when SSCN and FFCN are provided
The current driver uses input clock source frequency to calculate
values for [SS|FS]_[HC|LC] registers. However, when booting ACPI, we do not
currently have a good way to provide the frequency information.
Instead, we can leverage the SSCN and FFCN ACPI methods, which can be used
to directly provide these values. So, the clock information should
no longer be required during probing.

However, since clk can be invalid, additional checks must be done where
we are making use of it.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Loc Ho <lho@apm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:36:52 +01:00
Akshay Bhat
fa5b0bfa26 DT: i2c: trivial-devices: Add Epson RX8010 and MPL3115
Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:30:38 +01:00
Wolfram Sang
2fe3e51892 i2c: s3c2410: remove superfluous runtime PM calls
RuntimePM of the adapter device is now taken care of by the core. So, we
can remove these calls.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:27:53 +01:00
Wolfram Sang
9f924169c0 i2c: always enable RuntimePM for the adapter device
The adapter device is a logical device. Because of that, it already uses
pm_runtime_no_callbacks() in the core. To ensure proper propagation from
the children (i2c devices) to the parent of the adapter (the HW device),
make sure RuntimePM is enabled in any case.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:27:06 +01:00
Baruch Siach
8d22f30938 i2c: designware: retry transfer on transient failure
Set the i2c_adapter retries field to a sensible value. This allows the i2c core
to retry master_xfer() when it returns -EAGAIN. Currently the i2c-designware
driver returns -EAGAIN only on Tx arbitration failure (DW_IC_TX_ARB_LOST).

Reported-by: Rolland Chau <zourongrong@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 09:24:56 +01:00
Stephen Rothwell
f199b2605c i2c: ibm_iic: rename i2c_timings struct due to clash with generic version
Fixes: e1dba01ca6 ("i2c: add generic routine to parse DT for timing information")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-05 02:06:10 +01:00
Suravee Suthikulpanit
90708ce22b i2c: designware: Add support for AMD Seattle I2C
Add device HID AMDI0510 to match the I2C controlers on AMD Seattle platform

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-04 20:25:01 +01:00
Fabio Estevam
995e68a5ee i2c: imx: Remove unneeded comments
These multi-lines comments do not follow the standard kernel coding
style. In fact, they are not useful comments, so get rid of them.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-04 20:23:33 +01:00
Geliang Tang
66e784130a i2c: st: use to_platform_device()
Use to_platform_device() instead of open-coding it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:54:31 +01:00
Geliang Tang
238c44a70c i2c: designware: use to_pci_dev()
Use to_pci_dev() instead of open-coding it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:54:00 +01:00
Kamal Dasu
e2e5a2c618 i2c: brcmstb: Adding support for CM and DSL SoCs
Broadcoms DSL, CM (cable modem)and STB I2C core implementation have
8 data in/out registers that can transfer 8 bytes or 32 bytes max.
Cable and DSL "Peripheral" i2c cores use single byte per data
register and the STB can use 4 byte per data register transfer.
Adding support to take care of this difference. Accordingly added
the compatible string for SoCs using the "Peripheral" I2C block.

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:50:09 +01:00
Liguo Zhang
8378d01f60 i2c: mediatek: fix i2c multi transfer issue in high speed mode
For mt8173 platform with auto restart support, when doing i2c multi
transfer in high speed, we should ignore the first restart irq after
the master code, otherwise the first transfer will be discarded.

Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com>
Reviewed-by: Eddie Huang <eddie.huang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:38:22 +01:00
Gao Pan
e8e712916c i2c: imx: improve code readability
Replace of_get_named_gpio_flags with of_get_named_gpio because
the latter has less parameters, which improves code readability.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:17:29 +01:00
Fabio Estevam
5b66153989 i2c: imx: Improve message log when DMA is not used
When DMA cannot be used, it is better to state that the I2C controller
will operate in PIO mode.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:11:09 +01:00
Gao Pan
588eb93ea4 i2c: imx: add runtime pm support to improve the performance
In our former i2c driver, i2c clk is enabled and disabled in
xfer function, which contributes to power saving. However,
the clk enable process brings a busy wait delay until the core
is stable. As a result, the performance is sacrificed.

To weigh the power consumption and i2c bus performance, runtime
pm is the good solution for it. The clk is enabled when a i2c
transfer starts, and disabled after a specifically defined delay.

If CONFIG_PM is disabled the net result of this patch is that the
clock is never disabled.

Without the patch the test case (many eeprom reads) executes with approx:
real 1m7.735s
user 0m0.488s
sys 0m20.040s

With the patch the same test case (many eeprom reads) executes with approx:
real 0m54.241s
user 0m0.440s
sys 0m5.920s

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Gao Pan <b54642@freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[wsa: sorted includes]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:08:09 +01:00
Gao Pan
a5f650182b i2c: imx: init bus recovery info before adding i2c adapter
During driver probe, i2c_imx_init_recovery_info() must come before
i2c_add_numbered_adapter(), because the get/set_scl() functions
are assigned in i2c_register_adapter() under the conditon that bus
recover_info are initialized. Otherwise, get/set_scl() function
pointers never get assigned.

In such case, when i2c_generic_gpio_recovery() is used for bus recovery,
there will be kernel crash because bri->set_scl is NULL.

The solution to this bug is moving i2c_imx_init_recovery_info() before
i2c_register_adapter().

Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-01-03 19:06:50 +01:00
Wolfram Sang
7ee24eb508 i2c: rcar: disable PM in multi-master mode
In multi master mode, the IP core needs to be always active for
arbitration reasons. Get the config from DT and set up PM depending on
the config.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:11:48 +01:00
Wolfram Sang
42c0783b89 i2c: rcar: remove macros dealing with flags
These macros don't really hide complexity, but C idioms. Removing them
makes the code easier to read IMO and make a planned extension easier.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:11:21 +01:00
Wolfram Sang
0c739738a0 i2c: document binding for multi-master case
We need this binding because some I2C master drivers will need to adapt
their PM settings for the arbitration circuitry.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:10:32 +01:00
Sifan Naeem
c20821a7f0 i2c: img-scb: support repeated starts on IP v3.3
In version 3.3 of the IP when transaction halt is set, an interrupt
will be generated after each byte of a transfer instead of after
every transfer but before the stop bit.
Due to this behaviour we have to be careful that every time we
release the transaction halt we have to re-enable it straight away
so that we only process a single byte, not doing so will result in
all remaining bytes been processed and a stop bit being issued,
which will prevent us having a repeated start.

This change will have no effect on earlier versions of the IP.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:05:21 +01:00
Sifan Naeem
c7b0a7c107 i2c: img-scb: add handle for Master halt interrupt
Master halt is issued after each byte of a transaction is processed in
IP version 3.3.
Master halt will stall the bus by holding the SCK line low until the
halt bit in the scb_general_control is cleared.

After the last byte of a transfer is processed we can use the Master
Halt interrupt to facilitate a repeated start transfer without
issuing a stop bit.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:55 +01:00
Sifan Naeem
dd29207e6c i2c: img-scb: add handle for stop detected interrupt
Stop Detected interrupt is triggered when a Stop bit is detected on
the bus, which indicates the end of the current transfer.

When the end of a transfer is indicated by the Stop Detected interrupt,
drain the FIFO and signal completion for the transaction.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:30 +01:00
Sifan Naeem
a8c5a8d8c9 i2c: img-scb: remove fifo EMPTYING interrupts handle
Now that we are using the transaction halt interrupt to safely control
repeated start transfers, we no longer need to handle the fifo
emptying interrupts.

Handling this interrupt along with Transaction Halt interrupt can
cause erratic behaviour.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:05 +01:00
Sifan Naeem
c55ebe0e72 i2c: img-scb: support I2C_M_IGNORE_NAK
This commit adds support for the I2C_M_IGNORE_NAK protocol
modification.

Such behaviour can only be implemented in atomic mode. So, if a
transaction contains a message with such flag the drivers
switches to atomic mode. The implementation consists simply in
treating NAKs as ACKs.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:03:39 +01:00
Wolfram Sang
54177ccfbe i2c: make i2c_parse_fw_timings() always visible
This function used to be DT only, so it lived inside a CONFIG_OF block.
Now it uses device attributes and must be moved outside of it. No
further code changes, only one whitespace improvement.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-17 20:36:39 +01:00
Wolfram Sang
b7d518e6f4 i2c: emev: select I2C slave support
Until we have proper support to make I2C slave support fully optional,
select it to prevent build errors on randconfigs.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-17 20:34:36 +01:00
Måns Rullgård
5398b7ef6c i2c: xlr: add interrupt support for Sigma Designs chips
The Sigma Designs variant of this controller has the ability to generate
interrupts.  This is controlled using two additional registers, oddly
enough overlapping with the defined but unused HDSTATIM.

This patch adds support for using this feature instead of busy-looping
if an IRQ is specified.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-16 11:42:58 +01:00
Måns Rullgård
a45af72a60 i2c: xlr: fix extra read/write at end of rx transfer
The BYTECNT register holds the transfer size minus one.  Setting it to
the correct value removes the need for a dummy read/write at the end of
each transfer.  As zero-length transfers are not supported, do not
advertise I2C_FUNC_SMBUS_QUICK.

In other words, this patch makes the driver transfer the number of bytes
requested unless this is zero, which is not supported by the hardware
and is thus refused.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-16 11:42:30 +01:00
Måns Rullgård
75d31c2372 i2c: xlr: add support for Sigma Designs controller variant
Sigma Designs chips use a variant of this controller with the following
differences:

- The BUSY bit in the STATUS register is inverted
- Bit 8 of the CONFIG register must be set
- The controller can generate interrupts

This patch adds support for the first two of these.  It also calculates
and sets the correct clock divisor if a clk is provided.  The bus
frequency is optionally speficied in the device tree node.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-15 13:13:00 +01:00
Masahiro Yamada
51549c087f i2c: uniphier_f: error out if bus speed is zero
There is code to divide by "bus_speed" some lines below.
To eliminate the possibility of division by zero, bail out if
"clock-frequency" is specified as zero.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:59:46 +01:00
Masahiro Yamada
ac9b91f39d i2c: uniphier_f: error out if clock rate is zero
This input clock is used to generate the sampling clock for I2C bus.
If the clock rate is zero, there is something wrong with the clock
driver.  Bail out with the appropriate error message in such a case.
It would make it easier to find the root cause of failure.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:59:26 +01:00
Masahiro Yamada
2d5d23b96a i2c: uniphier: error out if bus speed is zero
There is code to divide by "bus_speed" some lines below.
To eliminate the possibility of division by zero, bail out if
"clock-frequency" is specified as zero.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:59:05 +01:00
Masahiro Yamada
1ff49b34bf i2c: uniphier: error out if clock rate is zero
This input clock is used to generate the sampling clock for I2C bus.
If the clock rate is zero, there is something wrong with the clock
driver.  Bail out with the appropriate error message in such a case.
It would make it easier to find the root cause of failure.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:58:44 +01:00
Wolfram Sang
ca68eade66 i2c: rcar: honor additional i2c timings from DT
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:10 +01:00
Wolfram Sang
c7881871de i2c: rcar: switch to i2c generic dt parsing
Switch to the new generic functions. Plain convert, no functionality
added yet.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:09 +01:00
Wolfram Sang
f9c9d31bdd i2c: rcar: refactor probe function a little
The probe function is a little bit messy, something here, something
there. Rework it so that there is some order: first init the private
structure, then the adapter, then do HW init. This also allows us to
remove the device argument of the clock calculation function, because it
now can be deduced from the private structure. Also, shorten some lines
where possible. This is a preparation for further refactoring.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:08 +01:00
Wolfram Sang
e1dba01ca6 i2c: add generic routine to parse DT for timing information
Inspired from the i2c-rk3x driver (thanks guys!) but refactored and
extended. See built-in docs for further information.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:07 +01:00
Wolfram Sang
99b809d7bd i2c: document generic DT bindings for timing parameters
Also, sort the properties alphabetically and make indentation
consistent. Wording largely taken from i2c-rk3x.txt, thanks guys!

Only "i2c-scl-internal-delay-ns" is new, the rest is used by two drivers
already and was documented in their driver binding documentation.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:39:01 +01:00
Niklas Söderlund
c31d0a0002 i2c: emev2: add slave support
Add I2C slave provider using the generic slave interface.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-05 19:55:36 +01:00
Paul Burton
7a852b02d4 i2c: eg20t: allow build on MIPS platforms
Allow the eg20t I2C driver to be built for MIPS platforms, in
preparation for use on the MIPS Boston board.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-03 22:11:47 +01:00
Paul Burton
a613d9d485 i2c: eg20t: set i2c_adapter->dev.of_node
Set the I2C adapter devices of_node to that of the PCI device, such that
I2C clients may be instantiated via device tree.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-03 22:11:46 +01:00
Ludovic Desroches
cc018e3612 i2c: at91: add support for the HOLD field
The hold field allows to configure the data hold time which can be set
with the help of the generic binding 'i2c-sda-hold-time-ns'. This
feature has been introduced with SAMA5D4 SoC family.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-03 21:42:37 +01:00
Wolfram Sang
d7a4c76336 i2c: piix4: remove unneeded assignments
smatch rightfully says:
drivers/i2c/busses/i2c-piix4.c:504 piix4_access warn: unused return: i = inb_p()
drivers/i2c/busses/i2c-piix4.c:537 piix4_access warn: unused return: i = inb_p()

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Christian Fetzer <fetzer.ch@gmail.com>
2015-12-03 21:36:55 +01:00
Liguo Zhang
173b77e8d8 i2c: mediatek: add i2c first write then read optimization
For platform with auto restart support, between every transfer,
i2c controller will trigger an interrupt and SW need to handle
it to start new transfer. When doing write-then-read transfer,
instead of restart mechanism, using WRRD mode to have controller
send both transfer in one request to reduce latency.

Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com>
Reviewed-by: Eddie Huang <eddie.huang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-01 01:55:45 +01:00
Shubhrajyoti Datta
948c58a03a i2c: cadence: Remove the suspended flag
The suspended flag is a flag holding the device's PM status.
The runtime framework does that for us.
Use pm_runtime_suspended call instead.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 21:08:07 +01:00
Shubhrajyoti Datta
7fa32329ca i2c: cadence: Move to sensible power management
Currently the clocks are enabled at probe and disabled at remove.
Which keeps the clocks enabled even if no transaction is going on.
This patch enables the clocks at the start of transfer and disables
after it.

Also adapts to runtime pm.

converts dev pm to const to silence a checkpatch warning.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 21:07:40 +01:00