In order to avoid the situation where the kthread is waiting for another
context to make the hardware idle let the message pump know if it's being
called from the worker thread context and if it isn't then defer to the
worker thread instead of idling the hardware immediately. This will ensure
that if this situation happens we block rather than busy waiting.
Signed-off-by: Mark Brown <broonie@kernel.org>
If we are using the standard SPI message pump (which all drivers should be
transitioning over to) then special case the message enqueue and instead of
starting the worker thread to push messages to the hardware do so in the
context of the caller if the controller is idle. This avoids a context
switch in the common case where the controller has a single user in a
single thread, for short PIO transfers there may be no need to context
switch away from the calling context to complete the transfer.
The code is a bit more complex than is desirable in part due to the need
to handle drivers not using the standard queue and in part due to handling
the various combinations of bus locking and asynchronous submission in
interrupt context.
It is still suboptimal since it will still wake the message pump for each
transfer in order to schedule idling of the hardware and if multiple
contexts are using the controller simultaneously a caller may end up
pumping a message for some random other thread rather than for itself,
and if the thread ends up deferring due to another context idling the
hardware then it will just busy wait. It can, however, have the benefit
of aggregating power up and down of the hardware when a caller performs
a series of transfers back to back without any need for the use of
spi_async().
Signed-off-by: Mark Brown <broonie@kernel.org>
cur_msg is updated under the queue lock and holds the message we are
currently processing. Since currently we only ever do removals in the
pump kthread it doesn't matter in what order we do things but we want
to be able to push things out from the submitting thread so pull the
check to see if we're currently handling a message before we check to
see if the queue is idle.
Signed-off-by: Mark Brown <broonie@kernel.org>
Since most devices now do use the standard queue and in order to avoid
initialisation ordering issues being introduced by further refactorings
to improve performance move the initialisation of the queue and the lock
for it to the main master allocation.
Signed-off-by: Mark Brown <broonie@kernel.org>
The device already asks the core to hold a runtime PM reference while it
is active so it is redundant to open code that in the driver itself.
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit c592becbe7 ("spi: fsl-(e)spi: migrate to generic master
queueing") the function fsl_spi_do_one_msg() is not void anymore, so return
an error code to avoid the following buid warning:
drivers/spi/spi-fsl-spi.c: In function 'fsl_spi_do_one_msg':
>> drivers/spi/spi-fsl-spi.c:374:4: warning: 'return' with no value, in function returning non-void [-Wreturn-type]
return;
^
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
kthread_run() could return ERR_PTR(-EINTR) from kthread_create_on_node().
Return the actual error code in spi_init_queue() instead of mangling it to
-ENOMEM.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The SET_PM_RUNTIME_PM_OPS() and SET_RUNTIME_PM_OPS() macros are
identical except that one of them is not empty for CONFIG_PM set,
while the other one is not empty for CONFIG_PM_RUNTIME set,
respectively.
However, after commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so one
of these macros is now redundant.
For this reason, replace SET_PM_RUNTIME_PM_OPS() with
SET_RUNTIME_PM_OPS() everywhere and redefine the SET_PM_RUNTIME_PM_OPS
symbol as SET_RUNTIME_PM_OPS in case new code is starting to use the
macro being removed here.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use (un)prepare_transfer_hardware calls to set fsl-espi to
low-power idle if not in use. Reference manual states:
"The eSPI is in a idle state and consumes minimal power.
The eSPI BRG is not functioning and the input clock is disabled"
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Migrates the fsl-(e)spi driver to use the generic master queuing.
Avoids the "master is unqueued, this is deprecated" warning.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The clk_disable() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
In 3-to-8 mux mode for the CS pins we need to set the PERI_SEL bit in the
control register. Currently the driver never sets this bit even when
configured for 3-to-8 mux mode. This patch adds code which sets the bit
during device initialization when necessary.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This will make it possible to use the settings specified in the devicetree
to configure the hardware.
Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Meson SPIFC driver uses regmap mmio functions and so it must
select REGMAP_MMIO to avoid the following build error:
spi-meson-spifc.c: undefined reference to `devm_regmap_init_mmio_clk'
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Exynos7 SPI controller supports only the auto Selection of
CS toggle mode and Exynos7 SoC includes six SPI controllers.
Add support for these changes in Exynos7 SPI controller driver.
Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There are two SPI controllers exported by PCI subsystem for Intel Quark X1000.
The SPI memory mapped I/O registers supported by Quark are different from
the current implementation, and Quark only supports the registers of 'SSCR0',
'SSCR1', 'SSSR', 'SSDR', and 'DDS_RATE'. This patch is to enable the SPI for
Intel Quark X1000.
This piece of work is derived from Dan O'Donovan's initial work for Intel Quark
X1000 SPI enabling.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Weike Chen <alvin.chen@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add OF notifier handler needed for creating/destroying spi devices
according to dynamic runtime changes in the DT live tree. This code is
enabled when CONFIG_OF_DYNAMIC is selected.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>
Dynamically inserting spi device nodes requires the use of a single
device registration method. Refactor the existing
of_register_spi_devices() to split out the core functionality for a
single device into a separate function; of_register_spi_device(). This
function will be used by the OF_DYNAMIC overlay code to make live
modifications to the tree.
Methods to lookup a device/master using a device node are added
as well, of_find_spi_master_by_node() & of_find_spi_device_by_node().
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely] Split patch into two pieces for clarity
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>
drivers/spi/spi-meson-spifc.c:171:6: sparse: symbol 'meson_spifc_setup_speed' was not declared. Should it be static?
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There are several registers for SPI, and the registers of 'SSCR0' and 'SSCR1'
are accessed frequently. This path is to introduce helper functions to
simplify the accessing of 'SSCR0' and 'SSCR1'.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Weike Chen <alvin.chen@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We can only use page_address on memory that has been mapped using kmap,
when the buffer passed to the SPI has been allocated by vmalloc the page
has not necessarily been mapped through kmap. This means sometimes
page_address will return NULL causing the pointer we pass to sg_init_one
to be invalid. Currently, this issue doesn't show up on the MXS
architecture as the defconfig defines CONFIG_HIGHMEM=n which means all
pages are mapped. For the sake of robustness though it is best to
correct the issue.
As we only call page_address so that we can pass a virtual address to
sg_init_one which will eventually call virt_to_page on it, fix this
by calling sg_set_page directly rather then relying on the sg_init_one
helper.
Note this patch is only build tested as I don't have an MXS system to
test on.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Return probe defer if requesting a dma channel without a dma controller
probed.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
All boards with a dma controller have DT support so using
dma_request_slave_channel_compat is no more needed.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This is a driver for the Amlogic Meson SPIFC (SPI flash controller),
which is one of the two SPI controllers available on the SoC. It
doesn't support DMA and has a 64-byte unified transmit/receive buffer.
The device is optimized for interfacing with SPI NOR memories and
allows the execution of standard operations such as read, page
program, sector erase, etc. in a simplified way, toggling a bit in a
dedicated register. The driver doesn't use those predefined commands
and relies only on custom transfers.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
On CPM1, when the SPI parameter RAM is relocated to somewhere else than the
default location, in accordance with freescale documentation
(refer micropatch SPI application note EB662), init RX/TX params command shall
not be used because it doesn't take into account the new location, and
overwrites data that is in original location of SPI param ram at addresses
SCC2 param base + (u32*)0x88 (u16*)0x90 (u32*)0x98 (u16*)0xA0, hence breaking
activity on SCC2 if SCC2 is used in a mode like QMC for instance.
Therefore, the action shall be done manually as described by freescale and as
was already partly done by the driver.
Reported-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
in SPI boot mode, romcode uses SPI controller to fetch data from NOR
flash. Here we need to reset the hardware IP to restore its state.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
if spi device has no frequency, spi core will setup the default frequency
to max_speed_hz of spi_master according to
int spi_setup(struct spi_device *spi)
{
...
if (!spi->max_speed_hz)
spi->max_speed_hz = spi->master->max_speed_hz;
...
}
this patch moves CSR SiRFSoC SPI frequency set to follow SPI core behaviour.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
commit 8c328a262f ("spi: sirf: Avoid duplicate code in various
bits_per_word cases") is wrong in setting data width register of
fifo is not right, it should use sspi->word_width >> 1 to set
related bits. According to hardware spec, the mapping between
register value and data width:
0 - byte
1 - WORD
2 - DWORD
Fixes: 8c328a262f ("spi: sirf: Avoid duplicate code in various bits_per_word cases") is wrong in setting data width register of
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Add support for the Synchronous Peripheral Flash Interface (SPFI) master
controller found on IMG SoCs. The SPFI controller supports 5 chip-select
lines and single/dual/quad mode SPI transfers.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We can only use page_address on memory that has been mapped using kmap,
when the buffer passed to the SPI has been allocated by vmalloc the page
has not necessarily been mapped through kmap. This means sometimes
page_address will return NULL causing the pointer we pass to sg_set_buf
to be invalid.
As we only call page_address so that we can pass a virtual address to
sg_set_buf which will then immediately call virt_to_page on it, fix this
by calling sg_set_page directly rather then relying on the sg_set_buf
helper.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
The call to spi_master_put() in rockchip_spi_remove() is redundant since
the master is registered using devm_. This patch removes it.
Signed-off-by: Laurentiu Palcu <laurentiu.palcu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently spidev allows callers to set the default speed by overriding the
max_speed_hz in the underlying device. This achieves the immediate goal but
is not what devices expect and can easily lead to userspace trying to set
unsupported speeds and succeeding, apart from anything else drivers can't
set a limit on the speed using max_speed_hz as they'd expect and any other
devices on the bus will be affected.
Instead store the default speed in the spidev struct and fill this in on
each transfer.
Signed-off-by: Mark Brown <broonie@kernel.org>
Instead of registering the irq name with the driver name, it's better to pass
the device name so that we have a more explicit indication as to what spi
instance the irq is related:
$ cat /proc/interrupts
CPU0
...
27: 0 - 98 80014000.ssp
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The assignment of SPI_GPIO_NO_CHIPSELECT to cs_gpios[0] causes the following
compiler warning, when building for 64 bit systems:
"warning: overflow in implicit constant conversion [-Woverflow]".
This is because the SPI_GPIO_NO_CHIPSELECT flag is a '-1' type casted to
unsigned long and cs_gpios is of the type int.
Furthermore the chip select's GPIO number is locally stored as unsigned int
and compared with SPI_GPIO_NO_CHIPSELECT. Thus the result of the comparison
is always false, if unsigned long and unsigned int have a different size.
As part of the fix this patch adds a check for the device tree's cs-gpios
property.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
An IOCTL call that calls spi_setup() and then dw_spi_setup() will
overwrite the persisted last transfer speed. On each transfer, the
SPI speed is compared to the last transfer speed to determine if the
clock divider registers need to be updated (did the speed change?).
This bug was observed with the spidev driver using spi-config to
update the max transfer speed.
This fix: Don't overwrite the persisted last transaction clock speed
when updating the SPI parameters in dw_spi_setup(). On the next
transaction, the new speed won't match the persisted last speed
and the hardware registers will be updated.
On initialization, the persisted last transaction clock
speed will be 0 but will be updated after the first SPI
transaction.
Move zeroed clock divider check into clock change test because
chip->clk_div is zero on startup and would cause a divide-by-zero
error. The calculation was wrong as well (can't support odd #).
Reported-by: Vlastimil Setka <setka@vsis.cz>
Signed-off-by: Vlastimil Setka <setka@vsis.cz>
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
If PM_RUNTIME is enabled, it is easy to trigger the following backtrace
on pxa2xx hosts:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at /home/lumag/linux/arch/arm/mach-pxa/clock.c:35 clk_disable+0xa0/0xa8()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00007-g1b3d2ee-dirty #104
[<c000de68>] (unwind_backtrace) from [<c000c078>] (show_stack+0x10/0x14)
[<c000c078>] (show_stack) from [<c001d75c>] (warn_slowpath_common+0x6c/0x8c)
[<c001d75c>] (warn_slowpath_common) from [<c001d818>] (warn_slowpath_null+0x1c/0x24)
[<c001d818>] (warn_slowpath_null) from [<c0015e80>] (clk_disable+0xa0/0xa8)
[<c0015e80>] (clk_disable) from [<c02507f8>] (pxa2xx_spi_suspend+0x2c/0x34)
[<c02507f8>] (pxa2xx_spi_suspend) from [<c0200360>] (platform_pm_suspend+0x2c/0x54)
[<c0200360>] (platform_pm_suspend) from [<c0207fec>] (dpm_run_callback.isra.14+0x2c/0x74)
[<c0207fec>] (dpm_run_callback.isra.14) from [<c0209254>] (__device_suspend+0x120/0x2f8)
[<c0209254>] (__device_suspend) from [<c0209a94>] (dpm_suspend+0x50/0x208)
[<c0209a94>] (dpm_suspend) from [<c00455ac>] (suspend_devices_and_enter+0x8c/0x3a0)
[<c00455ac>] (suspend_devices_and_enter) from [<c0045ad4>] (pm_suspend+0x214/0x2a8)
[<c0045ad4>] (pm_suspend) from [<c04b5c34>] (test_suspend+0x14c/0x1dc)
[<c04b5c34>] (test_suspend) from [<c000880c>] (do_one_initcall+0x8c/0x1fc)
[<c000880c>] (do_one_initcall) from [<c04aecfc>] (kernel_init_freeable+0xf4/0x1b4)
[<c04aecfc>] (kernel_init_freeable) from [<c0378078>] (kernel_init+0x8/0xec)
[<c0378078>] (kernel_init) from [<c0009590>] (ret_from_fork+0x14/0x24)
---[ end trace 46524156d8faa4f6 ]---
This happens because suspend function tries to disable a clock that is
already disabled by runtime_suspend callback. Add if
(!pm_runtime_suspended()) checks to suspend/resume path.
Fixes: 7d94a50585 (spi/pxa2xx: add support for runtime PM)
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Reported-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
In order to describe a single slave device that has no chip select line
the 'num-chipselects' property has to be <0> and the 'cs-gpios' property
doesn't need to be set.
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>