There are two bits which control the CS line in the CTRL0 register:
LOCK_CS and IGNORE_CRC. The latter would be better named DEASSERT_CS
in SPI mode.
LOCK_CS keeps CS asserted though the entire transfer. This should
always be set. The DMA code will always set it, explicitly on the
first segment of the first transfer, and then implicitly on all the
rest by never clearing the bit from the value read from the ctrl0
register.
The PIO code will explicitly set it for the first transfer, leave it
set for intermediate transfers, and then clear it for the final
transfer. It should not clear it.
The only reason to not set LOCK_CS would be to attempt an altered
protocol where CS pulses between each word. Though don't get your
hopes up if you want to do this, as the hardware doesn't appear to do
this in any sane manner. It appears to be related to the hardware
FIFO fill level.
The code can be simplified by just setting LOCK_CS once and then not
needing to deal with it at all in the PIO and DMA transfer functions.
Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
pm_runtime_put() wasn't called if clock rate could not be set up in
s3c64xx_spi_setup() leading to invalid count of device pm_runtime usage.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Mark device as PM runtime active during initialization to reflect
actual device power/clocks state. This reduces the enable count for SPI
bus controller gate clock so it can be disabled when the bus controller
is not used.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
This is more idiomatic for the factored out message processing and gives a
small simplification of the code since we always set the per-transfer
parameters in the same fashion.
Signed-off-by: Mark Brown <broonie@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
This is a half done conversion with minimal code reorganisation provided
for bisection purposes. A further patch will move the first transfer
preparation into tegra_slink_prepare_message().
The cs_change and udelay handling is removed, these should be
implemented by the framework and in any case are buggy - the two fields
should not be related and the cs_change handling appears to at best only
work the first time it's used in a message.
Signed-off-by: Mark Brown <broonie@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
User-visible strings are more difficult to grep from sources if they are
separated to multiple source lines. This is worse than over 80 columns long
line code style violation.
Fix this by making those to single-line strings or by breaking them between
variables.
While at there, convert if (printk_ratelimit()) dev_warn() to use
dev_warn_ratelimited in spi-pxa2xx.c.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
'of_match_ptr' is defined in linux/of.h. Include it explicitly.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
clock source is prepared and enabled by clk_prepare_enable()
in probe function, but no disable or unprepare in remove.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warnings.
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
WARNING: braces {} are not necessary for any arm of this statement
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warnings.
WARNING: space prohibited between function name and open parenthesis '('
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warning.
WARNING: space prohibited before semicolon
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warning.
WARNING: space prohibited before semicolon
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warnings.
WARNING: quoted string split across lines
WARNING: sizeof *spi should be sizeof(*spi)
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch errors and warnings.
ERROR: space required before the open brace '{'
ERROR: space required after that close brace '}'
ERROR: space required before the open parenthesis '('
ERROR: do not use C99 // comments
WARNING: sizeof *pp should be sizeof(*pp)
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warnings
WARNING: sizeof *cs should be sizeof(*cs)
WARNING: please, no space before tabs
WARNING: space prohibited between function name and open parenthesis '('
WARNING: line over 80 characters
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch warning.
WARNING: quoted string split across lines
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Fix the following checkpatch error and warnings.
ERROR: space required after that ',' (ctx:VxV)
WARNING: quoted string split across lines
WARNING: max() should probably be max_t(int, nb, master->num_chipselect)
WARNING: sizeof *spi should be sizeof(*spi)
WARNING: sizeof *master should be sizeof(*master)
WARNING: sizeof x should be sizeof(x)
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Change raw printk() call to dev_info() to provide a better message
to userspace so it can properly identify the device.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Change raw printk() call to dev_info() to provide a better message
to userspace so it can properly identify the device.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
The loops which SPI controller drivers use to process the list of transfers
in a spi_message are typically very similar and have some error prone areas
such as the handling of /CS. Help simplify drivers by factoring this code
out into the core - if drivers provide a transfer_one() function instead
of a transfer_one_message() function the core will handle processing at the
message level.
/CS can be controlled by either setting cs_gpio or providing a set_cs
function. If this is not possible for hardware reasons then both can be
omitted and the driver should continue to implement manual /CS handling.
This is a first step in refactoring and it is expected that there will be
further enhancements, for example factoring out of the mapping of transfers
for DMA and the initiation and completion of interrupt driven transfers.
Signed-off-by: Mark Brown <broonie@linaro.org>
This is of very little value in itself but will be useful once the loop
iterating over the transfers is also factored out into the core.
Signed-off-by: Mark Brown <broonie@linaro.org>
Many SPI drivers perform setup and tear down on every message, usually
doing things like DMA mapping the message. Provide hooks for them to use
to provide such operations.
This is of limited value for drivers that implement transfer_one_message()
but will be of much greater utility with future factoring out of standard
implementations of that function.
Signed-off-by: Mark Brown <broonie@linaro.org>
There is a minor fault about ACPI enumerated SPI devices with their modalias
attribute. Now modalias is set by device instance not by hardware ID.
For example "spi:INTABCD:00", "spi:INTABCD:01" etc.
This means each device instance gets different modalias which does match
with generated modules.alias. Currently this is not problem as matching can
happen also with "acpi:INTABCD" modalias.
Fix this by using ACPI hardware ID.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
The R8A7790 has QSPI module which added into RSPI together.
The transmit or receive data should be read from or written to
with the longword-, word-, or byte-access width. Modify word-
access to byte-access. In 16-bit data register, QSPI send or
receive datas access from high 8-bit while RSPI send or receive
datas access from low 8-bit on single mode.
Modify to reset transmit-receive buffer data and reading dummy
after data are transmited. RSPI has a TXMD bit on control
register(SPCR) to set transmit-only mode when transmit data or
Full-duplex synchronous mode when receive data. In QSPI the TXMD
bit is not supported, so after transmit data, dummy should be
read and before transmit or receive data the bufer register
should be reset.
This driver is the implementation of send and receive pio only,
DMA is not supported at this time.
Without this patch, it will occur error when transmit and receive
Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@linaro.org>
This patch fixes MCSPI FIFO buffer support when transmit-and-receive
(full duplex) mode is used. In this mode FIFO can be used for RX or
for TX or for both directions. If FIFO used for both directions the buffer
is split into two 32-byte buffers - one for each direction.
Also for full duplex mode both AEL and AFL need to be set in CHCONF0 register.
Signed-off-by: Illia Smyrnov <illia.smyrnov@globallogic.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
The variable efm32_spi_pdata_default origins from an earlier revision of
the patch introducing the driver, its use was dropped because of review
comments but I forgot to also drop the variable itself.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead. This converts the spi bus code to use the
correct field.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
The hardware level /CS handling is tied to the start of the data path so
is rolled into the same function as we use to manipulate GPIO /CS. In
order to support factoring out the /CS handling into the core separate the
two and explicitly start transfers separately to the /CS handling.
Signed-off-by: Mark Brown <broonie@linaro.org>
Provide tracepoints for the lifecycle of a message from submission to
completion and for the active time for masters to help with performance
analysis of SPI I/O.
Signed-off-by: Mark Brown <broonie@linaro.org>
Currently transfer_one_message() checks to see if the message consists of
a single spi_transfer and tells _start_transfer_one() but it just ignores
this. Don't bother.
Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
This call is needed to cleanup the resources requested by
spi_bitbang_start in the probe callback.
Noticed-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.
Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.
So now we have below patten for drivers using bitbang library:
probe:
spi_alloc_master -> Init reference count to 1
spi_bitbang_start -> Increment reference count
remove:
spi_bitbang_stop -> Decrement reference count
spi_master_put -> Decrement reference count (reference count reaches 0)
Fixup all users accordingly.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
'irq' was not released when clk_prepare_enable failed.
Fix it.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
The here used irq and threaded irq handler is a complete non-sense. After
the status register is read and the source disabled it schedules a thread
(the irq thread) to read the status from the variable, invoke complete()
and then renable the interrupt. Again: schedule a thread which invokes
_only_ complete().
This patch removes this non-sense and we remain with one handler which
invokes complete() if needed.
The device remove path should now disable the interupts.
This has been compile time tested.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
3e00a09d2f
(spi/hspi: Convert to core runtime PM)
enabled master->auto_runtime_pm.
Then, pm_runtime_enable() is required *before*
spi_register_master() calling.
This patch fixed it up.
Kernel will hang up with "spi_master spi0: Failed to power device: -13"
message without this patch.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
To help with bisection of future refactoring to share more of the code for
handling a spi_message pull the enabling of GPIO based /CS prior to all
the hardware setup for starting a transfer.
Signed-off-by: Mark Brown <broonie@linaro.org>
The hardware level /CS handling is tied to the start of the data path so
is rolled into the same function as we use to manipulate GPIO /CS. In
order to support factoring out the /CS handling into the core separate the
two and explicitly start transfers separately to the /CS handling.
Signed-off-by: Mark Brown <broonie@linaro.org>
Rather than using the driver custom platform data to store the chip select
GPIO use the cs_gpio field provided by the SPI core, supporting future
refectoring.
Signed-off-by: Mark Brown <broonie@linaro.org>
Ensure that the FIFOs are fully drained before we deassert /CS or do any
delays that have been requested in order to ensure that the behaviour
visible on the bus matches that which was requested by the caller.
Signed-off-by: Mark Brown <broonie@linaro.org>
Instead of getting the raw property, checking the length, and doing
endian conversion each time, use the OF function
of_property_read_u32() that does all that.
Error messages are slightly improved with error codes from
of_property_read_u32() for different ways the property may be invalid
(missing, too short, etc.)
Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
request_module() can handle format strings on its own, no need to create
the full module name ourself.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Otherwise we may try to start transfers immediately and then fail to
runtime resume the device causing us not to have clocks enabled.
Signed-off-by: Mark Brown <broonie@linaro.org>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Conflicts:
drivers/spi/spi-s3c64xx.c
The tegra114 driver wasn't currently handling the cs_change
functionality. cs_change is meant to invert the decisions of whether
or not to deactivate CS after each transfer. Without cs_change, after
every transfer (other than the last in the message) the normal behavior
is to leave CS active. For the last transfer, normally CS is
deactivated when the transfer is complete.
With cs_change set on a transfer (other than last one) CS would be
deactivated and the next transfer would need to activate it again. If
cs_change was set on the last tranfer in a message, then CS would be
left active when the message compeleted.
Also, this builds in logic so that if a different device tries to start
a transfer while CS is active from a different device, it will abort the
previous transfer and start a new one for the new device.
This splits tegra_spi_start_transfer_one into 2 functions, the new one
being tegra_spi_setup_transfer_one. The setup function is safe to call
on all transfers, sets up for the transfer, and handles the special case
of the first transfer in a message. In this special case, it needs to
know whether or not it needs to activate CS.
This work was based on the spi-atmel driver.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
devm_clk_get() is used so there is no reason to explicitly
call clk_put() in probe or remove functions.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Mark Brown <broonie@linaro.org>
Add dual/quad read mode bit flag for the master controller.
These check will be used in the spi framework to determine
whether the master controller can do dual/quad read respectively.
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Replace all symbols by simple dependency PLAT_SAMSUNG.
Signed-off-by: Mateusz Krawczuk <m.krawczuk@partner.samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove a duplicate put.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove unnecessary remove().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove a duplicate put.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove a duplicate put.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove a duplicate put.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove a duplicate put.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
If pci_iomap() returns NULL, adding "PCH_ADDRESS_SIZE * plat_dev->id"
can make it non-NULL which breaks the error handling.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Calling kfree() to clean up the memory obtained from spi_alloc_master() is
wrong as this is done in spi_master_release() when spi_master->dev's refcount
reaches zero.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Add compatibles for s3c6410, s5pc100 and s5pc110/s5pv210 boards.
Signed-off-by: Mateusz Krawczuk <m.krawczuk@partner.samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Also improve the error reporting on failure and remove a duplicate put.
This provides a small code saving.
Signed-off-by: Mark Brown <broonie@linaro.org>
This call is needed to cleanup the resources requested by
spi_bitbang_start in the probe callback.
Noticed-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.
Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.
So now we have below patten for drivers using bitbang library:
probe:
spi_alloc_master -> Init reference count to 1
spi_bitbang_start -> Increment reference count
remove:
spi_bitbang_stop -> Decrement reference count
spi_master_put -> Decrement reference count (reference count reaches 0)
Fixup all users accordingly.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Help simplify the cleanup code for SPI master drivers by providing a
managed master registration function, ensuring that the master is
automatically unregistered whenever the device is unbound.
Signed-off-by: Mark Brown <broonie@linaro.org>
subsys_init_call() initializes driver too early.
It's preventing to move DMA channel allocation at the begining
(driver probe).
This patch reduces and simplifies initalization code by
using module_platform_driver() macro.
It's also efficiently delaying driver startup.
Signed-off-by: Lukasz Czerwinski <l.czerwinski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
