There doesn't seem to be a way to empty TXFIFO on MMP2. The datasheet is
super-secret and the method described in Armada 16x manual won't work:
"The TXFIFO and RXFIFO are cleared to 0b0 when the SSPx port is reset or
disabled (by writing a 0b0 to the <Synchronous Serial Port Enable> field
in the SSP Control Register 0)."
# devmem 0xd4037008 # read SSSR
0x0000F204
# devmem 0xd4037000 32 0x07 # SSE off in SSCR0
# devmem 0xd4037000 32 0x87 # SSE on
# devmem 0xd4037008
0x0000F204
^ TXFIFO level is still 2. Sigh.
The OLPC 1.75 boot firmware leaves two bytes in the TXFIFO. Those are
basically throwaway bytes used in response to the messages from the EC.
The OLPC kernel copes with this by power-cycling the hardware. Perhaps
the firmware should do this instead.
Other than that, there's not much we can do other than complain loudly
until the garbage gets drained and discard the actual data... For the
OLPC EC this will work just fine and pushing more data to TXFIFO would
break further transactions.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Strobe a GPIO line when the slave TX FIFO is filled. This is how the
Embedded Controller on an OLPC XO-1.75 machine, that happens to be a SPI
master, learns that it can initiate a transaction.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Tested on an OLPC XO-1.75 machine, where the Embedded Controller happens
to be a SPI master.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Intel LPSS private register restoring in spi-pxa2xx.c: pxa2xx_spi_resume()
was added before there was no any other code restoring them. This was
changed after following commits for previous and current LPSS platforms:
c78b083066 ("ACPI / LPSS: custom power domain for LPSS")
41a3da2b8e ("mfd: intel-lpss: Save register context on suspend")
However there is one caveat: There is no LPSS private register context
save/restore for the Intel Lynxpoint in the Linux kernel code.
I did some debugging on one Lynxpoint based device I have and on it the
LPSS register context is not lost over suspend/resume cycle (s2idle).
Which happens for instance on Intel Braswell. I'm speculating but I guess
either firmware does it or the LPSS is kept always on Lynxpoint.
Given that we haven't needed to implement Lynxpoint LPSS I2C or UART
private register context save/restore over four years time I think we are
safe to remove this LPSS private register restoring during resume here.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The MMP2 platform, that uses device tree, has this controller. Let's add
devicetree alongside platform & PCI.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Rewrite switch code block to directly do the expected number
of shifts in each case and have break statements.
Addresses-Coverity-ID: 1056539 ("Missing break in switch")
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It makes no sense to remove the device on shutdown. And it break things
when the hardware crucial for shutdown (such as the embedded controller)
is attached to the SPI bus.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Mark Brown <broonie@kernel.org>
spi_controller_{suspend,resume}() already prints an error message on
failure, so there is no need to repeat this in individual drivers.
Note: spi_master_{suspend,resume}() is an alias for
spi_controller_{suspend,resume}().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Intel Ice Lake SPI host controller follows the Intel Cannon Lake but the
PCI IDs are different. Add the new PCI IDs to the driver supported
devices list.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
clk_prepare_enable() can fail, so its return value should be checked and
acted upon.
Found by Linux Driver Verification project (linuxtesting.org).
Fixes: 3343b7a6d2 ("spi/pxa2xx: convert to the common clk framework")
Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Convert the pump_transfers() transfer tasklet to transfer_one() hook the
SPI core calls to process single transfer instead of handling message
processing and chip select handling in the driver. This not only
simplifies the driver but also brings transfer statistics from the core.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We are going to rename and modify pump_transfers(). Prepare for it by
removing the string "pump_transfers:" from error and warning prints.
While at it make these user-visible strings single line in sources as it
helps source grepping from error reports.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current DMA engine implementation of pxa2xx_spi_dma_prepare() don't use
the dma_burst argument. Remove it since it became unused after
commit 6356437e65 ("spi: spi-pxa2xx: remove legacy PXA DMA bits").
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Don't leave runtime PM enabled in case devm_spi_register_controller()
returns with an error. Otherwise runtime PM will complain when driver is
reloaded:
[ 693.855811] pxa2xx-spi pxa2xx-spi.13: Unbalanced pm_runtime_enable!
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Convert to generalized SPI controller API introduced by the
commit 8caab75fd2 ("spi: Generalize SPI "master" to "controller"").
Inside driver variable name "master" is still used to indicate the driver
is master only.
While at it, change "unsigned cs" to "unsigned int cs" in
pxa2xx_spi_fw_translate_cs() to suppress checkpatch warning.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Move SSP idle waiting before CS deassert from error and end of message
handling function giveback() to cs_deassert(). This ensures idle waiting
is done also if there is CS change between transfers.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
gpiod_free() is an internal function for gpiolib, gpiod_put() is the
correct external function.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
gpio_free(gpio) simply does gpiod_free(gpio_to_desc(gpio)), so it's
simpler and cleaner to use gpiod_free directly.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
We still need to request/free GPIOs passed via the legacy path of
pxa2xx_spi_chip::gpio_cs, but we can use the gpiod API otherwise.
Consistently use the descriptor API instead of the legacy one.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
GPIO descriptors, when being requested, may configure pin at the same
time. In case of SPI chip select we shouldn't do any assumptions of the
state of pin since we don't know yet what chip is connected there and if
it uses high or low active state. So, leave the state of pin as is until
transfer will start.
Fixes: 99f499cd65 ("spi: pxa2xx: Add support for GPIO descriptor chip selects")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westeberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a valid case to call setup() following by setup_cs() several
times for the same chip.
With the commit
676a4e3bab ("spi: pxa2xx: Only claim CS GPIOs when the slave device is created")
it is not possible anymore due to GPIO line being requested already
during the first call to setup_cs().
For now, revert the commit to make things work again.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Avoid hogging chip select GPIOs just because they are listed for the
master. They might be mulitplexed and, if no slave device is attached,
used for different purposes. Moreover, this strategy avoids having to
allocate a cs_gpiods structure.
Tested on the IOT2000 where the second SPI bus is connected to an
Arduino-compatible connector and multiplexed between SPI, GPIO and PWM
usage.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Intel Cannonlake LPSS SPI has up to four chip selects per port like in
Broxton and is clocked like Sunrisepoint and Kaby Lake. Add a new type
LPSS_CNL_SSP and configuration that enable runtime chip select detection
and use the same FIFO thresholds than in Sunrisepoint.
Patch adds support for both Cannonlake SoC and PCH.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When using the a device with edge-triggered interrupts, such as MSIs,
the interrupt handler has to ensure that there is a point in time during
its execution where all interrupts sources are silent so that a new
event can trigger a new interrupt again.
This is achieved here by disabling all interrupt sources for a moment
before processing them according to the status register. If a new
interrupt should have arrived after we read the status, it will now
re-trigger the interrupt, even in edge mode.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Gemini Lake reuses the same LPSS SPI configuration as Broxton
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
As suggested by Andy Shevchenko: Decouple this corner cause from the
general handling logic in ssp_int.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The commit 7c7289a404 ("spi: pxa2xx: Default thresholds to PXA
configuration") while splitting up CE4100 code obviously missed a break
condition in one chunk. Add it here.
Looks like we have no active user of CE4100, though better to fix this later
than never.
Fixes: commit 7c7289a404 ("spi: pxa2xx: Default thresholds to PXA configuration")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Kbuild test robot reports:
drivers/spi/spi-pxa2xx.c: In function ‘setup_cs’:
drivers/spi/spi-pxa2xx.c:1190:20: error: implicit declaration of function ‘desc_to_gpio’
...
Reason for this is the fact that those functions are declared in
linux/gpio/consumer.h which is not included in the driver. Fix this by
including it.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver uses custom chip_info coming from platform data for chip selects
implemented as GPIOs. If the system lacks board files setting up the
platform data, it is not possible to use GPIOs as chip selects.
This adds support for GPIO descriptors so that regardless of the underlying
firmware interface (DT, ACPI or platform data) the driver can request GPIOs
used as chip selects and configure them accordingly.
The custom chip_info GPIO support is still left there to make sure the
existing systems keep working as expected.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Most of the devices in the supported list have PXA configuration of FIFO. In
particularly Intel Medfield and Merrifield have bigger FIFO, than it's defined
for CE4100.
Split CE4100 in the similar way how it was done for Intel Quark, i.e. prefix
definitions by CE4100 and append necessary pieces of code to switch case
conditions.
We are on safe side since those bits are ignored on all LPSS IPs.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Transfer state machine in this driver does not need to set/unset pointer
to chip data between queueing and finalizing message as it is not
actually used as a state info itself but just pointer passing.
Since this per SPI device specific chip data is already carried in
ctldata use that and remove pointer to chip data from driver data.
While at it, group initialized variables before uninitialized variables
in pump_transfers().
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is no need to carry pointer to current SPI message in driver data
because cur_msg in struct spi_master holds it already when driver is using
the message queueing infrastructure from the SPI core.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
All of these variables are unconditionally set before their use.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It seems the commit e5262d0568 ("spi: spi-pxa2xx: SPI support for Intel Quark
X1000") misses one place to be adapted for Intel Quark, i.e. in reset_sccr1().
Clear all RFT bits when call reset_sccr1() on Intel Quark.
Fixes: e5262d0568 ("spi: spi-pxa2xx: SPI support for Intel Quark X1000")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Kaby Lake PCH-H has the same SPI host controller as Skylake. Add these new
PCI IDs to the list of supported devices.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI core provides DMA mapping with scatterlists. Start using it instead
of own implementation in spi-pxa2xx. Major difference in addition to
bunch of removed boilerplate code is that SPI core does
mapping/unmapping for all transfers in a message before and after the
message sending where spi-pxa2xx did mapping/unmapping for each
transfers separately.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We will find more use for struct spi_master pointer in pump_transfers()
and code will be more readable if we access it using local pointer than
through the drv_data->master.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently, even if the PXA2xx SPI master supports DMA, it won't be
enabled unless (i) the slave device is enumerated through ACPI, or
(ii) the slave device is registered with board-specific
controller_data specified. Even then, there isn't a field in the
controller_data that explicitly enables dma - it just gets enabled
if the master supports it and controller_data is non-NULL.
This means that drivers which register SPI devices on a bus without
awareness of this controller cannot avail of DMA performance gains.
This patch allows DMA transfers to be used if supported.
Signed-off-by: Dan O'Donovan <dan@emutex.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Certain Intel Sunrisepoint PCH variants report zero chip selects in SPI
capabilities register even they have one per port. Detection in
pxa2xx_spi_probe() sets master->num_chipselect to 0 leading to -EINVAL
from spi_register_master() where chip select count is validated.
Fix this by not using SPI capabilities register on Sunrisepoint. They don't
have more than one chip select so use the default value 1 instead of
detection.
Fixes: 8b136baa58 ("spi: pxa2xx: Detect number of enabled Intel LPSS SPI chip select signals")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Fix cs_change management so that it is in line with other spi drivers.
In the spi core api helpers such as spi_bus_lock/unlock and spi_sync_locked
or cs_change field in spi_transfer help to manage chip select from the
device driver.
The driver was setting the chip select to idle if the message queue was
empty despite cs_change or other status field set by spi_bus_lock/unlock
or spi_sync_locked.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Dummy buffer is used for half duplex transfers that don't have TX or RX
buffer set. Instead of own dummy buffer management here let the SPI core to
handle it by setting the SPI_MASTER_MUST_RX and SPI_MASTER_MUST_TX flags.
Then core makes sure both transfer buffers are set.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>