Description:
On Armada 38x, the device SPI interface supports frequencies of up to
50 MHz. However, due to this erratum, when the device core clock is
250 MHz and the SPI interfaces is configured for 50MHz SPI clock and
CPOL=CPHA=1, there might occur data corruption on reads from the SPI
device.
Workaround:
Work in one of the following configurations:
1. Set CPOL=CPHA=0 in "SPI Interface Configuration Register".
2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1 Register"
before setting the interface.
[gregory.clement@free-electrons.com}: port to v4.2-rc, use
is_errata_50mhz_ac instead of using a new ARMADA_380_SPI spi type.
Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch fixes endian warnings detected by sparse:
- sparse: incorrect type in argument 1 (different base types)
expected unsigned int [unsigned] val
got restricted __le32 [usertype] <noident>
- sparse: incorrect type in argument 1 (different base types)
expected unsigned int [unsigned] val
got restricted __le32 [usertype] <noident>
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Remove extra space and make the alias matches driver name.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Definitions from linux/platform_data/atmel.h are not used, remove the
include.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-img-spfi.c: In function 'img_spfi_setup':
drivers/spi/spi-img-spfi.c:446: warning: 'ret' may be used
uninitialized in this function.
Fixes: commit b03ba9e314 ("spi: img-spfi: fix multiple calls to request gpio")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Remove null_dma_buf variable and extra allocation for it. It is not needed
since 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>
spfi_setup may be called many times by the spi framework, but
gpio_request_one can only be called once without freeing, repeatedly
calling gpio_request_one will cause an error to be thrown, which
causes the request to spi_setup to be marked as failed.
We can have a per-spi_device flag that indicates whether or not the
gpio has been requested. If the gpio has already been requested use
gpio_direction_output to set the direction of the gpio.
Fixes: 8c2c8c03cd ("spi: img-spfi: Control CS lines with GPIO")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Fix inconsistent indenting in spidev_open, no functional change.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
These became unused by the 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>
Major difference in LPSS SPI between Intel Sunrisepoint PCH and earlier
platforms is an integrated DMA (iDMA) engine. iDMA is an IP that is private
for each LPSS host controller (UART/SPI/I2C). Other differences are private
register space offset, a few private registers that are in different
location and FIFO thresholds.
Intel Sunrisepoint LPSS SPI and iDMA devices are probed and registered in
MFD layer as platform devices. Here these compound devices are detected by
matching against known PCI IDs. This allows us to share
pxa2xx_spi_acpi_get_pdata() for setting up the platform data instead of
duplicating it in MFD part.
This patch adds configuration for Intel Sunrisepoint LPSS SPI, above
detection and DMA filter function that picks the DMA channel only from an
associated iDMA block.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The I2C core always reports the MODALIAS uevent as "i2c:<client name"
regardless if the driver was matched using the I2C id_table or the
of_match_table. So the driver needs to export the I2C table and this
be built into the module or udev won't have the necessary information
to auto load the correct module when the device is added.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This resulted in the use of polling mode when other approaches
(dma or interrupts) would have been more appropriate.
Happened for transfers longer than 477 bytes.
Reported-by: Noralf Tronnes <noralf@tronnes.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
When using reverse polarity for clock (spi-cpol) on a device
the clock line gets altered after chip-select has been asserted
resulting in an additional clock beat, which confuses hardware.
This did not show when using native-CS, as the same register
is used to control cs as well as polarity, so the changes came
into effect at the same time. Unfortunately this is not true
with gpio-cs.
To avoid this situation this patch moves the setup of polarity
(spi-cpol and spi-cpha) outside of the chip-select into
prepare_message, which is run prior to asserting chip-select.
Also fixes resetting 3-wire mode after use of rx-mode, so that
a 3-Wire sequence TX, RX, TX works as well (right now it runs
TX, RX, RX instead)
Reported-by: Noralf Tronnes <noralf@tronnes.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch fixes a regression introduced by commit 232a5adc51 ("spi:
bitbang: only toggle bitchanges"). The attempt to optimize writes of
consecutive bit patterns broke most of the combinations of word size
and SPI modes due to selecting the wrong bit as the MSB value.
Fixes: 232a5adc51 (spi: bitbang: only toggle bitchanges)
Signed-off-by: Lars Persson <larper@axis.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Calling spfi_wait_all_done is not required if the transfer has timed
out before all data is transferred.
spfi_wait_all_done polls for Alldone interrupt which is triggered to
mark the transfer as complete and to indicate it is now safe to issue
a new transfer.
Fixes: 8c2c8c0 ("spi: img-spfi: Control CS lines with GPIO")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Printing the FIFO depth does not add much noise in the log and can be useful
for debugging transfer issues.
Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
For spi without dma channel and use can_dma(), it can
use master->dev for struct device.
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit ddcad7e906 omap2_mcspi_set_cs() is called without
runtime power management requested. This patch fixes the problem by
requesting runtime power management in omap2_mcspi_set_cs().
Reported-By: Pali Rohár <pali.rohar@gmail.com>
Fixes: ddcad7e906 (spi: omap2-mcspi: Fix native cs with new set_cs)
Tested-By: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently the pre-scaler limit is incorrect. The value differs slightly
for various devices so a single value can't be used. Using the compatible
field select the correct pre-scaler limit.
Add new compatible field value for Keystone devices to support their
unique pre-scaler limit value.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Within davinci_spi_get_prescale() the prescale has two meanings. First one
being the calculated prescale value and then at the end translates it to the
prescale value that will be written to the SPI register.
At first glance this can be confusing especially when comparing the minimum
prescale value against what is seen in the TRM.
To simplify things make it clear that the calculated prescale value will always
be based on the value that will be written into the SPI register.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
DMA transfers must be greater than the watermark level size. spi_imx->rx_wml
and spi_imx->tx_wml contain the watermark level in 32bit words whereas struct
spi_transfer contains the transfer len in bytes. Fix the check if DMA is
possible for a transfer accordingly. This fixes transfers with sizes between
33 and 128 bytes for which previously was claimed that DMA is possible.
Fixes: f62caccd12 (spi: spi-imx: add DMA support)
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
This fixes several warnings like:
drivers/spi/spi-mpc512x-psc.c: In function 'mpc512x_psc_spi_prep_xfer_hw':
arch/powerpc/include/asm/io.h:163:2: warning: '__ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
introduced in commit 8bf960985d for some build configurations.
Fixes: 8bf960985d ("spi: mpc512x-psc: add support for Freescale MPC5125")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The register layout of the PSC devices differ between MPC5121 and
MPC5125, but the registers are named nearly identical and their purpose
is similar enough ("freescale identical") such that substituting
mpc52xx_psc by mpc5125_psc is nearly enough to make the driver work on
MPC5125. To keep supporting MPC5121 this patch introduces a cpp
macro to select the right struct that defines the register layout.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. Remove the include here because this is a
provider driver.
Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a missing break statement here so selecting both only selects
upper.
Fixes: dfe11a11d5 ('spi: Add support for Zynq Ultrascale+ MPSoC GQSPI controller')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since spidev is no more allowed to use in DT and is really loudly warned about
it I'd like to add this compatible value.
(Geert Uytterhoeven wrote: "Add the compatible value for your device to the
spidev_dt_ids[] array in drivers/spi/spidev.c.")
Signed-off-by: Mark Brown <broonie@kernel.org>
per spi-master statistics accessible as:
/sys/class/spi_master/spi*/statistics/*
per spi-device statistics accessible via:
/sys/class/spi_master/spi*/spi*.*/statistics/*
The following statistics are exposed as separate "files" inside
these directories:
* messages number of spi_messages
* transfers number of spi_transfers
* bytes number of bytes transferred
* bytes_rx number of bytes transmitted
* bytes_tx number of bytes received
* errors number of errors encounterd
* timedout number of messages that have timed out
* spi_async number of spi_messages submitted using spi_async
* spi_sync number of spi_messages submitted using spi_sync
* spi_sync_immediate number of spi_messages submitted using spi_sync,
that are handled immediately without a context switch
to the spi_pump worker-thread
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit a483dcbfa2 ("ARM: shmobile: lager: Remove legacy
board support"), R-Car Gen2 SoCs are only supported in generic DT-only
ARM multi-platform builds. The driver doesn't need to match platform
devices by name anymore, hence remove the corresponding
platform_device_id entry.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>
Memory for struct rockchip_spi is allocated by spi_alloc_master()
using kzalloc() so it doesn't need to be set to 0 one more time.
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Memory for this struct is allocated by spi_alloc_master() using
kzalloc() so it doesn't need to be set to 0 one more time.
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
spi_map_buf() processes mapping of vmalloc-ed buffers in a special way,
making mapping of every page separately. However, if the buffer is not
aligned to page boundary (e.g. sub-array in a vmalloc-ed array), it
fills the scatter table with page-size unaligned pieces, that cross
page boundaries. This is incorrect and can, for example, cause memory
corruption and various crashes when working with ubifs on spi-nor chips
(though those drivers are themselves buggy in that they should be
providing DMAable memory to the SPI framework).
Fix this by using proper scatter table size and intra-page buffer lengths,
so that the whole buffer splits into separate scatter table entries on
page boundaries.
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Maximum speed supported by spfi is limited to 1/4 of the spfi clock.
But in some SoCs the maximum speed supported by the spfi block can
be limited to less than 1/4 of the spfi clock. In such cases we have
to define the limit in the device tree so that the driver can pick
it up.
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
qspi_set_send_trigger() returns an unsigned value, so make it return
"unsigned int".
Update the loop variables qspi_trigger_transfer_out_int() to match the
above.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Just use "ret" instead, for consistency with other similar functions.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Setting the Same Edge bit indicates to the spfi block to receive and
transmit data on the same edge of the spfi clock, which in turn
doubles the operating frequency of spfi.
The maximum supported frequency is limited to 1/4th of the spfi input
clock, but without this bit set the maximum would be 1/8th of the
input clock.
The current driver calculates the divisor with maximum speed at 1/4th
of the input clock, this would fail if the requested frequency is
higher than 1/8 of the input clock. Any requests for 1/8th of the
input clock would still pass.
Fixes: 8543d0e72d ("spi: img-spfi: Limit bit clock to 1/4th of input clock")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
The latest SPI controllers embedded inside sama5d2x SoCs come with FIFOs.
When FIFOs are enabled, they can either work in SINGLE data mode or
MULTIPLE data mode. The selected mode depends on the configuration of the
SPI controller (see below).
In SINGLE data mode (or legacy mode), for a single I/O access, only one
data can be read from the Receive Data Register (RDR) or written into the
Transmit Data Register (TDR). On the other hand, in MULTIPLE data mode, up
to 4 data can be read from the RDR or up 2 data can be written into the
TDR in a single 32bit I/O access. So programmers should take good care of
the width of the I/O access to read/write the right number of data. The
exact number of read/written data depends on both the I/O access width and
the data width (from 8 up to 16 bits).
To enable the FIFO feature a "atmel,fifo-size" property must be set to
provide the maximum number of data (not bytes) the RX and TX FIFOs can
store. Hence a 32 data FIFO can always store up to 32 data unrelated with
the actual data width.
When FIFOs are enabled, the RX one is forced to operate in SINGLE data
mode because this driver configures the spi controller as a master. In
master mode only, the Received Data Register has an additionnal Peripheral
Chip Select field, which prevents us from reading more than a single data
at each register access.
Besides, the TX FIFO operates in MULTIPLE data mode. However, even when a
8bit data size is used, only two data by access could be written into the
Transmit Data Register. Indeed the first data has to be written into the
lowest 16 bits whereas the second data has to be written into the highest
16 bits of the TDR. When DMA transfers are used to send data, we don't
rework the transmit buffer to cope with this hardware limitation: the
additional copies required to prepare a new input buffer suited to both
the DMA controller and the spi controller would waste all the benefit of
the DMA transfer. Instead, the DMA controller is configured to write only
one data at time into the TDR.
In pio mode, two data are written in the TDR in a single access.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Constify the ACPI device ID array, it doesn't need to be writable at
runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds support for GQSPI controller driver used by
Zynq Ultrascale+ MPSoC
Signed-off-by: Ranjit Waghmode <ranjit.waghmode@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI hardware spec for Keystone specify a lower value of 0 for pre-scale
divider which determine what max value of spi clock (spi-max-frequency)
the device can support. This translates to a clock divider of 2. So fix
the lower limit value used for the boundary check in
davinci_spi_get_prescale() function to 1 so that a maximum of spi device
clock rate / 2 is possible to be set for spi-max-frequency.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In current driver, we increase actual_length in the following way:
message->actual_length += dspi_xxx_transfer()
It has two defects.
First, transmitting maybe in process when the function call finished and
we don't know the transmitting result in this moment.
Secondly, the last sentence in function before returning is accessing the
SPI register and trigger the data transmitting. If we enable interrupt,
interrupt may be generated before function return and we also have the same
sentence "message->actual_length += dspi_xxx_transfer()"
in the IRQ handler.
And usually dspi_xxx_transfer will trigger a new IRQ.
The original dspi_xxx_transfer call may return when no new IRQ generate.
This may mess the variable spi_message->actual_length.
Now we increase the variable in the IRQ handler and only when we get the
TCF or EOQ interrupt
And we get the transmitted data length from the SPI transfer counter
instead of the function return value.
Signed-off-by: Haikun Wang <haikun.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
DSPI module has two optional interrupts when complete data transfer.
One is EOQ interrupt, the other one is TCF interrupt.
EOQ indicates a queue of data frame has been transmitted.
TCF indicates a frame has been transmitted.
This patch enable support TCF mode.
Driver binds a correct interrupt mode to every compatible string.
User should use the correct compatible string in the dts node.
Signed-off-by: Haikun Wang <haikun.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch relies on the CSAAT (Chip Select Active After Transfer) feature
introduced by the version 2 of the spi controller. This new mode allows to
use properly the internal chip-select output pin of the spi controller
instead of using external gpios. Consequently, the "cs-gpios" device-tree
property becomes optional.
When the new CSAAT bit is set into the Chip Select Register, the internal
chip-select output pin remains asserted till both the following conditions
become true:
- the LASTXFER bit is set into the Control Register (or the Transmit Data
Register)
- the Transmit Data Register and its shift register are empty.
WARNING: if the LASTXFER bit is set into the Control Register then new
data are written into the Transmit Data Register fast enough to keep its
shifter not empty, the chip-select output pin remains asserted. Only when
the shifter becomes empty, the chip-select output pin is unasserted.
When the CSAAT bit is clear in the Chip Select Register, the LASTXFER bit
is ignored in both the Control Register and the Transmit Data Register.
The internal chip-select output pin remains active as long as the Transmit
Data Register or its shift register are not empty.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Generic DMA support was already implemented by commit cd7bed0034
("spi/pxa2xx: break out the private DMA API usage into a separate file")
which moved all the legacy PXA DMA implementation code into its own
file.
With generic DMA available for PXA, we can now just trash this file.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Mark Brown <broonie@linaro.org>
[respin after pxa dmaengine support upstream]
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
General register located in LPSS SPI private register space is not found in
upcoming Intel LPSS platforms. Access it conditionally depending is it
defined in configuration.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some of the Intel LPSS SPI properties will be different in upcoming
platforms compared to existing Lynxpoint and BayTrail/Braswell. LPSS SPI
private registers will be at different offset and there will be changes in
individual registers and default FIFO thresholds too.
Add configuration for these differences and use them in runtime based on
LPSS SSP type. With this change private registers offset autodetection
becomes needless.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Intel LPSS SPI properties differ between between platforms. Now private
registers offset 0x400 or 0x800 is autodetected but there is need to
support also other offset and handle a few other differences.
Prepare for that by splitting the LPSS_SSP type into compatible hardware
types and set it now based on PCI or ACPI ID. That type will be used to set
properties that differ between current and upcoming platforms.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The case where spi_master sets the flags SPI_MASTER_MUST_RX/TX while
CONFIG_HAS_DMA is unset (which is unlikley) together with a driver
that reuses spi_messages with rx/tx_buff set to NULL, can result in:
* data disclosure over the SPI (for tx_buf == NULL)
* memory corruption (for rx_buf == NULL)
This happenes when dummy_rx/dummy_tx are changing address due to krealloc
or free and an allocation of the memory by a different part of the kernel.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
To reduce complexity of code, drop "ret" then qspi_transfer_out_in function
should return the value of "qspi_trigger_transfer_out_in" directly.
Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
The name of "qspi_trigger_transfer_out_int" function should be
"qspi_trigger_transfer_out_in" without "t".
Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
The commit df59fa7f4b "spi: orion: support armada extended baud
rates" made the assumptions that all the Armada SoCs supported the
same maximum frequency. However, according the hardware datasheet, the
maximum frequency supported by the Armada 370 SoC is tclk/4, for the
Armada XP, Armada 38x and Armada 39x SoCs the limitation is 50MHz and
for the Armada 375 it is tclk/15.
This patch introduces new compatible strings to handle all these
case. In order to be future proof a compatible was created for each
SoC even if currently some SoCs seem using the same IP.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
USP-based SPI need a disable and enable, otherwise it doesn't work.
this patch adds it as HW initialization.
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>
this job has been done by spi core.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
The commit df59fa7f4b "spi: orion: support armada extended baud
rates" was too optimistic for the maximum baud rate that the Armada
SoCs can support. According to the hardware datasheet the maximum
frequency supported by the Armada 370 SoC is tclk/4. But for the
Armada XP, Armada 38x and Armada 39x SoCs the limitation is 50MHz and
for the Armada 375 it is tclk/15.
Currently the armada-370-spi compatible is only used by the Armada 370
and the Armada XP device tree. On Armada 370, tclk cannot be higher
than 200MHz. In order to be able to handle both SoCs, we can take the
minimum of 50MHz and tclk/4.
A proper solution is adding a compatible string for each SoC, but it
can't be done as a fix for compatibility reason (we can't modify
device tree that have been already released) and it will be part of a
separate patch.
Fixes: df59fa7f4b (spi: orion: support armada extended baud rates)
Reported-by: Kostya Porotchkin <kostap@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
If a valid GPIO is specified but cannot be requested by the driver, print a
message and error out of omap2_mcspi_setup.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The OMAP2_MCSPI_CHCONF_FORCE must be toggled even when using GPIO
chip selects. This patch conditionally calls the omap2_mcspi_set_cs
function to do so when using GPIO chip selects.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The core spi driver swaps the polarity of the enable based on SPI_CS_HIGH.
The omap2 controller has an internal configuration register bit called
OMAP2_MCSPI_CHCONF_EPOL to handle active high chip selects as well.
So we have to revert swap the polarity back for the correct setting of the
OMAP2_MCSPI_CHCONF_FORCE bit in omap2_mcspi_set_cs.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The core spi driver handles the delay between transactions.
This is a remanant from the transfer_one conversion.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Incorrect condition is used in spin_event_timeout(). When the TX is
done, the SPIE_NF bit in ESPI_SPIE register is set to 1 to indicate the
Tx FIFO is not full. If the bit is 0, it indicates the Tx FIFO is full.
Due to this error, if the Tx FIFO is full at the beginning, but becomes
not full after handling the Rx FIFO (the SPIE_NF bit is set), the
spin_event_timeout() returns with timeout occurred. It causes the
interrupt handler not to send completion notification to the thread that
called wait_for_complete() waiting for the notification.
Signed-off-by: Jane Wan <Jane.Wan@gainspeed.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI chip select signal need to keep asserted between several
spi_transfer in the same spi_message usually.
But the driver will de-assert CS signal and the assert it between
serval spi_transfer in the same spi_message under some condiations.
This patch fix the bug.
Here is an example:
Assume you have two variables like the following,
struct spi_transfer a;
struct spi_transfer b;
if you send a spi_message only includes 'a' first,
and then you send a spi_message includes 'a' and 'b'
but without resetting 'a'.
Driver will de-assert CS and then assert CS between 'a' and 'b'.
Signed-off-by: Haikun Wang <haikun.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
USP is a general purpose serial port in SiRFSoC, which can work as SPI.
the most data flow of USP and pure SPI is same with main differences
in registers layout.
this patch moves registers layout to private data, and use flags to
differentiate other minor differences between prima2-spi, prima2-usp
and atlas7-usp for hardware configuration.
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>
GPIO chip select patch series appears to have broken the native chip select
support. This patch pulls the manual native chip select toggling out of
the transfer_one routine and adds a set_cs routine.
Tested natively on AM3354 with SPI serial flash on spi0cs0.
Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Michael Welling <mwelling@ieee.org>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
fixes several warnings/error emmitted by the kbuild system:
* warn: cast from pointer to integer of different size
using size_t instead of u32
* error: 'SZ_4K' undeclared
moved to PAGE_SIZE and PAGE_MASK instead
Review showed also a typo in the same code where tx_buff
was checked twice instead of checking both rx and tx_buff.
Reported by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Conditions per spi_transfer are:
* transfer.len >= 96 bytes (to avoid mapping overhead costs)
* transfer.len < 65536 bytes (limitaion by spi-hw block - could get extended)
* an individual scatter/gather transfer length must be a multiple of 4
for anything but the last transfer - spi-hw block limit.
(some shortcut has been taken in can_dma to avoid unnecessary mapping of
pages which, for which there is a chance that there is a split with a
transfer length not a multiple of 4)
If it becomes a necessity these restrictions can get removed by additional
code.
Note that this patch requires a patch to dma-bcm2835.c by Noralf to
enable scatter-gather mode inside the dmaengine, which has not been
merged yet.
That is why no patch to arch/arm/boot/dts/bcm2835.dtsi is included - the
code works as before without dma when tx/rx are not set, but it writes
a message warning about dma not used:
spi-bcm2835 20204000.spi: no tx-dma configuration found - not using dma mode
To enable dma-mode add the following lines to the device-tree:
dmas = <&dma 6>, <&dma 7>;
dma-names = "tx", "rx";
Tested-by: Noralf Trønnes <noralf@tronnes.org> (private communication)
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix a race (with some kernel configurations) where a queued
master->pump_messages runs and frees dummy_tx/rx before
spi_unmap_msg is running (or is finished).
This results in the following messages:
BUG: Bad page state in process
page:db7ba030 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x200(arch_1)
page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
...
Reported-by: Noralf Trønnes <noralf@tronnes.org>
Suggested-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
A few driver fixes plus two changes for the core, one to make the
setup_transfer() callback optional which fixes crashes in some drivers
which were updated to use new interfaces without apparent testing and
one to ensure we don't expose the data buffers we use for dummy
transfers to drivers which avoids potential issues with multiple
accesses to them or reuse.
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Merge tag 'spi-v4.1-rc1' into spi-linus
spi: Fixes for v4.1
A few driver fixes plus two changes for the core, one to make the
setup_transfer() callback optional which fixes crashes in some drivers
which were updated to use new interfaces without apparent testing and
one to ensure we don't expose the data buffers we use for dummy
transfers to drivers which avoids potential issues with multiple
accesses to them or reuse.
# gpg: Signature made Sat 25 Apr 2015 10:59:47 BST using RSA key ID 5D5487D0
# gpg: key CD7BEEBC: no public key for trusted key - skipped
# gpg: key CD7BEEBC marked as ultimately trusted
# gpg: key AF88CD16: no public key for trusted key - skipped
# gpg: key AF88CD16 marked as ultimately trusted
# gpg: key 16005C11: no public key for trusted key - skipped
# gpg: key 16005C11 marked as ultimately trusted
# gpg: key 5621E907: no public key for trusted key - skipped
# gpg: key 5621E907 marked as ultimately trusted
# gpg: key 5C6153AD: no public key for trusted key - skipped
# gpg: key 5C6153AD marked as ultimately trusted
# gpg: Good signature from "Mark Brown <broonie@sirena.org.uk>"
# gpg: aka "Mark Brown <broonie@debian.org>"
# gpg: aka "Mark Brown <broonie@kernel.org>"
# gpg: aka "Mark Brown <broonie@tardis.ed.ac.uk>"
# gpg: aka "Mark Brown <broonie@linaro.org>"
# gpg: aka "Mark Brown <Mark.Brown@linaro.org>"
Remove unneeded variable used to store return value.
The semantic patch that makes this change is available
in scripts/coccinelle/misc/returnvar.cocci.
More information about semantic patching is available at
http://coccinelle.lip6.fr/
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If GPIO chip select is specified, request the GPIO in the setup function
and release it in the cleanup function.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Switches from transfer_one_message to transfer_one to prepare driver for
use of GPIO chip selects.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
To reduce indentation and complexity of code, insteeds of returning zero
the function rspi_dma_check_then_transfer should return rspi_dma_transfer
directly after checking error.
Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
move spi controller's gpio request work out from probe() to spi device
register stage, so after spi device register spi controller can deactive
device's gpio chipselect. old code can't do it because gpio request has
not be done until device register is finised in spi_bitbang_start.
and add cleanup function to free CS gpio.
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>
The GPIO subsystem provides dummy GPIO consumer functions if GPIOLIB is
not enabled. Hence drivers that depend on GPIOLIB, but use GPIO consumer
functionality only, can still be compiled if GPIOLIB is not enabled.
Relax the dependency on GPIOLIB if COMPILE_TEST is enabled, where
appropriate.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
I got following error on CONFIG_GPIOLIB=n.
drivers/spi/spi-bcm2835.c: In function 'chip_match_name':
drivers/spi/spi-bcm2835.c:356:21: error: dereferencing pointer to incomplete type 'struct gpio_chip'
return !strcmp(chip->label, data);
^
drivers/spi/spi-bcm2835.c: In function 'bcm2835_spi_setup':
drivers/spi/spi-bcm2835.c:382:9: error: implicit declaration of function 'gpiochip_find' [-Werror=implicit-function-declaration]
chip = gpiochip_find("pinctrl-bcm2835", chip_match_name);
^
drivers/spi/spi-bcm2835.c:382:7: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
chip = gpiochip_find("pinctrl-bcm2835", chip_match_name);
^
drivers/spi/spi-bcm2835.c: In function 'chip_match_name':
drivers/spi/spi-bcm2835.c:357:1: warning: control reaches end of non-void function [-Wreturn-type]
}
^
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
return error for unsupported bits-per-word format, BUG() is not right
for this scenerios as we are not an ASSERT but an error handler.
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>
The polling mode of the driver is designed for transfers that run
less than 30us - it will only execute under those circumstances.
So it should run comfortably without getting interrupted by the
scheduler.
But there are situations where the raspberry pi is so overloaded
that it can take up to 80 jiffies until the polling thread gets
rescheduled - this has been observed especially under heavy
IO situations.
In such a situation we now fall back to the interrupt handler and
log the situation at debug level.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The way that the timeout code is written in the polling function
the timeout does also trigger when interrupted or rescheduled while
in the polling loop.
This patch changes the timeout from effectively 20ms (=2 jiffies) to
1 second and removes the time that the transfer really takes out of
the computation, as - per design - this is <30us and the jiffie resolution
is 10ms so that does not make any difference what so ever.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The internal chip select CS0 wasn't initialized properly to work with
CS HIGH chips.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Clocks should be prepared and unprepared, fix this by using
clk_prepare_enable() and clk_disable_unprepare() instead of
clk_enable() and clk_disable().
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Set the OF node of the spi controller and use the generic GPIO based
chip select instead of the custom controller data. As the controller
data isn't used by any board just drop it.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch makes possible for protocol drivers to do full-duplex SPI
transfers properly. Until now this driver could only be used for
half-duplex transfers, since it always expected an spi_transfer with
non-null tx_buf to be only used for TX, and those with non-null rx_buf
to be only used for RX.
The fix consists in correcting the fsl_espi_transfer length by taking
into consideration duplex spi_transfers, and not just by adding n_tx
and n_rx.
Furthermore, this correction has exposed an inconsistency in the
protocol driver <-> controller driver interaction. The spi-fsl-espi
driver artificially inserts TX bytes when message fragmentation is
necessary (due to SPCOM_TRANLEN_MAX) instead of informing the
protocol driver of the hardware limitation. This was tested with the
m25p80 NOR flash protocol driver. Since fixing this issue may cause
other client drivers to malfunction, it was left as is.
Signed-off-by: Jonatas Rech <jonatas.rech@datacom.ind.br>
Signed-off-by: Mark Brown <broonie@kernel.org>
devm_ioremap_resource() doesn't return NULL but an ERR_PTR on error.
Reported-by: Jonas Gorsky <jogo@openwrt.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
LS1021A chip also has the DSPI module.
Add it to the dependence.
Signed-off-by: Haikun Wang <haikun.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It is unnecessary for DSPI to enable/disable clk when access DSPI register.
And it will reduce efficiency.
Signed-off-by: Haikun Wang <haikun.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi queue waits forever for spi_finalize_current_message() to be
called, blocking the bus. Ensure that all error paths from
omap2_mcspi_transfer_one_message() call spi_finalize_current_message().
Signed-off-by: Fionn Cleary <fionn.cleary@streamunlimited.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This has the benefit that the "optimization" of the framework in regards
to spi_sync will also benefit spidev users directly and allow running
spi transfers without a necessary context-switch to message-pump.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
On CPM2, the SPI parameter RAM is dynamically allocated in the
dualport RAM whereas in CPM1, it is statically allocated to a default
address with capability to relocate it somewhere else via the use of
CPM micropatch. The address of the parameter RAM is given by the boot
loader and expected to be mapped via devm_ioremap_resource()
In the current implementation, in function fsl_spi_cpm_get_pram()
there is a confusion between the SPI_BASE register and the base of the
SPI parameter RAM. Fortunatly, it is working properly with MPC866 and
MPC885 because they do set SPI_BASE, but on MPC860 and other old
MPC8xx that doesn't set SPI_BASE, pram_ofs is not properly set.
Also, the parameter RAM is not properly mapped with
devm_ioremap_resource() as it should but still gets accessible by
chance through the full RAM which is mapped from somewhere else.
This patch applies to the SPI driver the same principle as for the
CPM UART: when the CPM is of type CPM1, we simply do an
devm_ioremap_resource() of the area provided via the device tree.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
As it turns out, the set_cs() enable parameter refers to the logic level
on the CS pin, not the state of chip selection.
This broke functionality of the LEDs behind the CPLD, or at least delayed
the commands until another one came in to toggle CS.
Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This driver mediates access between the connected CPLD and other devices
on the bus.
The m25p80-compatible boot flash and (some models) MMC use regular SPI,
bitbanged as required by the SoC. However the SPI-connected CPLD has
a two-wire mode, in which two bits are transferred per SPI clock
cycle. The second bit is transmitted with the SoC's CS2 pin.
Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some controller drivers have no need of this callback (spi-altera even
causes a NULL pointer dereference because it doesn't register the callback,
falsely assuming that it is already optional).
Fixes: 30af9b558a ("spi/bitbang: Drop empty setup() functions")
Signed-off-by: Pelle Nilsson <per.nilsson@xelmo.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@vanguardiasur.com.ar>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some spi device drivers use the same tx_buf and rx_buf repeatly for better
performance such as driver/input/touchsreen/ads7846.c, but spi core grab tx_buf
/rx_buf of transfer and set them as dummy_tx/dummy_rx once they are NULL. Thus,
in the second time the tx_buf/rx_buf will be replaced by dummy_tx/dummy_rx and
the data which produced by the last tx or rx may be wrongly sent to the device
or handled by the upper level protocol. This patch just keep the orignal value
of tx_buf/rx_buf if they are NULL after this transfer processed.
Signed-off-by: Robin Gong <b38343@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The way that the timeout code is written in the polling function
the timeout does also trigger when interrupted or rescheduled while
in the polling loop.
This patch changes the timeout from effectively 20ms (=2 jiffies) to
1 second and removes the time that the transfer really takes out of
the computation, as - per design - this is <30us and the jiffie resolution
is 10ms so that does not make any difference what so ever.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix:
drivers/spi/spi-bcm2835.c: In function 'chip_match_name':
drivers/spi/spi-bcm2835.c:356:21: error:
dereferencing pointer to incomplete type
drivers/spi/spi-bcm2835.c: In function 'bcm2835_spi_setup':
drivers/spi/spi-bcm2835.c:382:2: error:
` implicit declaration of function 'gpiochip_find'
drivers/spi/spi-bcm2835.c:387:21: error:
dereferencing pointer to incomplete type
by adding the now mandatory GPIOLIB dependency.
Fixes: a30a555d74 ("spi: bcm2835: transform native-cs to gpio-cs
on first spi_setup")
Cc: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
In cases of short transfer times the CPU is spending lots of time
in the interrupt handler and scheduler to reschedule the worker thread.
Measurements show that we have times where it takes 29.32us to between
the last clock change and the time that the worker-thread is running again
returning from wait_for_completion_timeout().
During this time the interrupt-handler is running calling complete()
and then also the scheduler is rescheduling the worker thread.
This time can vary depending on how much of the code is still in
CPU-caches, when there is a burst of spi transfers the subsequent delays
are in the order of 25us, so the value of 30us seems reasonable.
With polling the whole transfer of 4 bytes at 10MHz finishes after 6.16us
(CS down to up) with the real transfer (clock running) taking 3.56us.
So the efficiency has much improved and is also freeing CPU cycles,
reducing interrupts and context switches.
Because of the above 30us seems to be a reasonable limit for polling.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Transforms the bcm-2835 native SPI-chip select to their gpio-cs equivalent.
This allows for some support of some optimizations that are not
possible due to HW-gliches on the CS line - especially filling
the FIFO before enabling SPI interrupts (by writing to CS register)
while the transfer is already in progress (See commit: e3a2be3030)
This patch also works arround some issues in bcm2835-pinctrl which does not
set the value when setting the GPIO as output - it just sets up output and
(typically) leaves the GPIO as low. When a fix for this is merged then this
gpio_set_value can get removed from bcm2835_spi_setup.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
When the CONTINUE bit is set, the interrupt status we are polling to
identify if a transaction has finished can be sporadic. Even though
the transfer has finished, the interrupt status may erroneously
indicate that there is still data in the FIFO. This behaviour causes
random timeouts in large PIO transfers.
Instead of using the CONTINUE bit to control the CS lines, use the SPI
core's CS GPIO handling. Also, now that the CONTINUE bit is not being
used, we can poll for the ALLDONE interrupt to indicate transfer
completion.
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Imagination has recommended that the SPFI controller be reset after
each message, regardless of success or failure. Do this in an
unprepare_message() callback.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver can be greatly simplified by moving the transfer timeout
handling to a handle_err() callback.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Setting the transfer length in the TRANSACTION register after the
CONTROL register is programmed causes intermittent timeout issues in
SPFI transfers when using the SPI framework to control the CS GPIO
lines. To avoid this issue, set transfer length before programming
the CONTROL register.
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
If a driver doesn't implement the master->handle_err() callback and an
SPI transfer fails, the kernel will crash with a NULL pointer
dereference:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0003000
[00000000] *pgd=80000040004003, *pmd=00000000
Internal error: Oops: 80000206 [#1] SMP ARM
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc7-koelsch-05861-g1fc9fdd4add4f783 #1046
Hardware name: Generic R8A7791 (Flattened Device Tree)
task: eec359c0 ti: eec54000 task.ti: eec54000
PC is at 0x0
LR is at spi_transfer_one_message+0x1cc/0x1f0
Make the master->handle_err() callback optional to avoid the crash.
Also fix a spelling mistake in the callback documentation while we're at
it.
Fixes: b716c4ffc6 ("spi: introduce master->handle_err() callback")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Although the SPFI BITCLK divider supports a value of up to 255, only
values up to 128 are usable. This results in a maximum possible bit
clock rate of 1/4th the input clock rate.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In preparation for switching to using the SPI core's CS GPIO handling,
move setup of the PORT_STATE register, which must be configured before
CS is asserted, to a prepare_message() callback.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add delay between chip select and clock signals, before clock starts and
after clock stops.
Signed-off-by: Aaron Brice <aaron.brice@datasoft.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Previous algorithm had an outer loop with the values {2,3,5,7} and an
inner loop with {2,4,6,8,16,32,...,32768}, and would pick the first
value over the required scaling value (where the total scale was the two
numbers multiplied).
Since the inner loop went up to 32768 it would always pick a value of 2
for PBR and a much higher than necessary value for BR. The desired
scale factor was being divided by two I believe to compensate for the
much higher scale factors (the divide by two not specified in the
reference manual).
Updated to check all values and find the smallest scale factor possible
without going over the desired clock rate.
Signed-off-by: Aaron Brice <aaron.brice@datasoft.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We need "ret" to be unsigned for the error handling to work. The
signedness of "i" and "n" don't matter but qspi_set_send_trigger()
returns an int so I've changed them to int as well.
Fixes: 4b6fe3edcb ('spi: Using Trigger number to transmit/receive data')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
They are used to decide if the controller can do DMA on a buffer
of a specific length and thus are needed before any transfer is attempted.
This fixes a memory leak where the SPI core uses the drivers can_dma()
callback to determine if a buffer needs to be mapped. As the watermark
levels aren't correct at that point the driver falsely claims to be able to
DMA the buffer when it fact it isn't.
After the transfer has been done the core uses the same callback to
determine if it needs to unmap the buffers. As the driver now correctly
claims to not being able to DMA the buffer the core doesn't attempt to
unmap the buffer which leaves the SGT leaking.
Fixes: f62caccd12 (spi: spi-imx: add DMA support)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
cr_width may be not initialized before using by cr, the related warning
(with defconfig under blackfin by gcc5):
CC drivers/spi/spi-bfin5xx.o
drivers/spi/spi-bfin5xx.c: In function 'bfin_spi_pump_transfers':
drivers/spi/spi-bfin5xx.c:655:5: warning: 'cr_width' may be used uninitialized in this function [-Wmaybe-uninitialized]
cr |= cr_width;
^
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The current implementation of bitbang_txrx_be_cpha0 and
bitbang_txrx_be_cpha1 always call setmosi. That runs into several
unnecessary calls into the gpiolib when the level of the GPIO actually
has not to be changed.
This patch changes the routines to remember the last GPIO level
and only calls setmosi if an change has to be made. This
way it improves the transfer throughput.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
We refactored this code but accidentally left out a break statement so
QUARK_X1000_SSP isn't handled correctly.
Fixes: 025ffe88ee ('spi: pxa2xx: shift clk_div in one place')
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Previous algorithm had an outer loop with the values {2,3,5,7} and an
inner loop with {2,4,6,8,16,32,...,32768}, and would pick the first
value over the required scaling value (where the total scale was the two
numbers multiplied).
Since the inner loop went up to 32768 it would always pick a value of 2
for PBR and a much higher than necessary value for BR. The desired
scale factor was being divided by two I believe to compensate for the
much higher scale factors (the divide by two not specified in the
reference manual).
Updated to check all values and find the smallest scale factor possible
without going over the desired clock rate.
Signed-off-by: Aaron Brice <aaron.brice@datasoft.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to transmit and receive data when have 32 bytes of data that
ready has prepared on Transmit/Receive Buffer to transmit or receive.
Instead transmits/receives a byte data using Transmit/Receive Buffer
Data Triggering Number will improve the speed of transfer data.
Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
To reduce the number of interrupts/message we fill the FIFO before
enabling interrupts - for short messages this reduces the interrupt count
from 2 to 1 interrupt.
There have been rare cases where short (<200ns) chip-select switches with
native CS have been observed during such operation, this is why this
optimization is only enabled for GPIO-CS.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Tested-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since spidev is a detail of how Linux controls a device rather than a
description of the hardware in the system we should never have a node
described as "spidev" in DT, any SPI device could be a spidev so this
is just not a useful description.
In order to help prevent users from writing such device trees generate a
warning if spidev is instantiated as a DT node without an ID in the match
table.
Signed-off-by: Mark Brown <broonie@kernel.org>
This also allows for GPIO-CS to get used removing the limitation of
2/3 SPI devises on the SPI bus.
Fixes: spi-cs-high with native CS with multiple devices on the spi-bus
resetting the chip selects to "normal" polarity after a finished
transfer.
No other functionality/improvements added.
Tested with the following 4 devices on the spi-bus:
* mcp2515 with native CS
* mcp2515 with gpio CS
* fb_st7735r with native CS
(plus spi-cs-high via transistor inverting polarity)
* enc28j60 with gpio-CS
Tested-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We have found that we can sometimes see read failures on boards with
high-capacitance SPI lines. It seems that the controller samples the Rx
data line too early, and its register interface has an "Rx Sample Delay"
setting to fine-tune against this issue.
This patch adds a new optional device tree entry that can configure this
delay in terms of nanoseconds. The kernel will calculate the
best-fitting amount of parent clock ticks to program the controller with
based on that.
Signed-off-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Rockchip SPI driver currently calculates its clock rate divisor by
integer dividing the parent rate by the target rate, and then rounding
the result up to the next even number (since the divisor must be
even).
Clock rate divisors should always be rounded up, so that the resulting
frequency is lower or equal to the target. This is correctly done in the
second step here but not in the first, so we still have a risk of
exceeding the desired target frequency (e.g. setting spi-max-frequency
to 40000000 with a parent clock of 99000000 could lead to a divisor of
99000000 / 40000000 == 2 (which is even) that then results in an
effective frequency of 99000000 / 2 == 49500000 (potentially exceeding
the flash chip's specifications).
This patch changes the division to round up to fix this problem.
Signed-off-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Trying to register an SPI device asynchronously (via async_schedule() call)
results in an ugly complaint from request_module() warning about potential
deadlock (because request_module tries to wait for async works to
complete, the caller is also an async work in this case).
While we could try to switch to using request_module_nowait(), other buses,
as well as SPI itself when not using device tree, do not try to load
modules explicitly, but rather rely on the standard infrastructure (such as
udev) to execute module loading. There is no reason why SPI OF-described
devices should be treated differently.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The commit 1a7b7ee72c (spi: Ensure that CS line is in non-active state after
spi_setup()) introduces an unconditional call of spi_set_cs() before ->setup().
The dw_spi_set_cs() relies on that fact that ->setup() is already called, but
it doesn't now. This patch fixes the crash by adding an additional check to
dw_spi_set_cs().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Quark SoC data sheet describes the baud rate setting using fractional
divider. The subset of possible values represented by a table suggests that the
divisor has one block that could divide by 5. This explains the number of the
beast in some cases in the table. Thus, in this particular case the divisor can
be evaluated as
5^i * 2^j * 2 * k,
where
i = [0, 1]
j = [0, 23]
k = [1, 256]
There are few cases as mentioned in the data sheet, i.e. better form of the
clock signal will be in case if DDS_CLK_RATE either 2^n or 2/5. It's also
possible to use any value that is less or equal to 0x33333 (1/5/16 = 1/80).
All three cases are compared to each other and the one that suits better is
chosen by the approximation algorithm. Anyone can play with the script [1] that
represents the algorithm.
[1] https://gist.github.com/06b084488b3629898121
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch refactors ssp_get_clk_div() and pxa2xx_ssp_get_clk_div() to align
clk_div calculations, i.e. ssp_get_clk_div() and quark_x1000_set_clk_regvals()
will return plain clk_div and it will be shifted to proper position in
pxa2xx_ssp_get_clk_div().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
`spidev_message()` sums the lengths of the individual SPI transfers to
determine the overall SPI message length. It restricts the total
length, returning an error if too long, but it does not check for
arithmetic overflow. For example, if the SPI message consisted of two
transfers and the first has a length of 10 and the second has a length
of (__u32)(-1), the total length would be seen as 9, even though the
second transfer is actually very long. If the second transfer specifies
a null `rx_buf` and a non-null `tx_buf`, the `copy_from_user()` could
overrun the spidev's pre-allocated tx buffer before it reaches an
invalid user memory address. Fix it by checking that neither the total
nor the individual transfer lengths exceed the maximum allowed value.
Thanks to Dan Carpenter for reporting the potential integer overflow.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
The official documentation is wrong in this respect.
Has been tested empirically for dividers 2-1024
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Implement the recommendation from the BCM2835 data-sheet
with regards to polling drivers to fill/drain the FIFO as much data as possible
also for the interrupt-driven case (which this driver is making use of).
This means that for long transfers (>64bytes) we need one interrupt
every 64 bytes instead of every 12 bytes, as the FIFO is 16 words (not bytes) wide.
Tested with mcp251x (can bus), fb_st7735 (TFT framebuffer device)
and enc28j60 (ethernet) drivers.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
asm/irq.h is already included by linux/interrupt.h.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
These asm/io.h, asm/irq.h and asm/delay.h are needless since they are
already included by linux/io.h via drivers/spi/spi-pxa2xx.h,
linux/interrupt.h and linux/delay.h.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use the endian agnositc IO functions instead of the __raw ones for when
the driver is in use on big-endian systems.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The following errors/warnings issued by checkpatch.pl --strict have been fixed:
drivers/spi/spi-bcm2835.c:182: CHECK: Alignment should match open parenthesis
drivers/spi/spi-bcm2835.c:191: CHECK: braces {} should be used on all arms of this statement
drivers/spi/spi-bcm2835.c:234: CHECK: Alignment should match open parenthesis
drivers/spi/spi-bcm2835.c:256: CHECK: Alignment should match open parenthesis
drivers/spi/spi-bcm2835.c:271: CHECK: Alignment should match open parenthesis
drivers/spi/spi-bcm2835.c:346: CHECK: Alignment should match open parenthesis
total: 0 errors, 0 warnings, 6 checks, 403 lines checked
In 2 locations the arguments had to get split/moved to the next line so that the
line width stays below 80 chars.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
With spidev the mesg->complete callback points to spidev_complete.
Calling this unblocks spidev_sync and so spidev_sync_write finishes. As
the struct spi_message just read is a local variable in
spidev_sync_write and recording the trace event accesses this message
the recording is better done first. The same can happen for
spidev_sync_read.
This fixes an oops observed on a 3.14-rt system with spidev activity
after
echo 1 > /sys/kernel/debug/tracing/events/spi/enable
.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Altera's Arria10 SoC interconnect requires a 32-bit write for APB
peripherals. The current spi-dw driver uses 16-bit accesses in
some locations. This patch converts all the 16-bit reads and
writes to 32-bit reads and writes.
Additional Documentation to Support this Change:
The DW_apb_ssi databook states:
"All registers in the DW_apb_ssi are addressed at 32-bit boundaries
to remain consistent with the AHB bus. Where the physical size of
any register is less than 32-bits wide, the upper unused bits of
the 32-bit boundary are reserved. Writing to these bits has no
effect; reading from these bits returns 0." [1]
[1] Section 6.1 of dw_apb_ssi.pdf (version 3.22a)
Request for test with platforms using the DesignWare SPI IP.
Tested On:
Altera CycloneV development kit
Altera Arria10 development kit
Compile tested for build errors on x86_64 (allyesconfigs)
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Reviewed-and-tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently the omap100k driver uses prepare and unprepare transfer hardware
to enable and disable clocks for the IP block. Since these functions are
called along with runtime PM and end up duplicating its functionality in a
less flexible fashion we are trying to phase them out so convert this
driver to do runtime PM instead.
While doing so add missing error handling and remove a redundant NULL
assignment.
Signed-off-by: Mark Brown <broonie@kernel.org>
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some devices samples state of the chip select signal during power up
and act differently based on this state, so SPI core should ensure
that CS line is driven in non-active state after spi_setup().
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Instead of clearing the RxU, RxO, and TxO IRQs individually with
3 register reads, a single read of the ICR register will do the
same thing.
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
intel_mid_dma seems to be unmaintained for a long time. Moreover, the IP block
of DMA itself is the same in both dw_dmac and intel_mid_dma. This patch moves
spi-dw-midpci to use dw_dmac driver.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI core has a comprehensive function set to map and unmap a message when it's
needed. This patch converts driver to use that advantage.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch shuts up any ongoing DMA transfer in case of error.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In according to documentation SPI in DMA mode may encounter underrun/overrun
failures in rare cases. When such failure occurs, an error recovery protocol is
expected to be implemented in the device driver so that the failed transaction
can be restarted.
This patch enables FIFO overrun / underrun interrupts in DMA case and adds a
handler for that.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The patch splits DMA preparatory code to dma_setup() callback. The change also
converts transfer_one() to program DMA whenever the transfer is DMA mapped. The
change is a follow up of the converion to use SPI core transfer_one_message().
Since the DMA mapped transfers can be interleaved with PIO ones the DMA related
configuration should respect that.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
DMAEngine has a specific type to be used for bus width. This patch converts the
code to use the values of the specific type when configure DMA transfer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Remove Kconfig dependency and enable driver for
all ARCHs.
Also update help description.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
All SPI drivers have been converted from legacy suspend/resume callbacks to
dev_pm_ops. So we can finally remove support for legacy PM from the SPI
core.
Since there aren't any special bus specific things to do during
suspend/resume and since the PM core will automatically fallback directly to
using the device's PM ops if no bus PM ops are specified there is no need to
have any special SPI bus PM ops.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The logic of DMA completion is broken now since test_and_clear_bit() never
returns the other bit is set. It means condition are always false and we have
spi_finalize_current_transfer() called per each DMA completion which is wrong.
The patch fixes logic by clearing BUSY bit first and then check for the other
one.
Fixes: 30c8eb52cc (spi: dw-mid: split rx and tx callbacks when DMA)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch adds DMA capabilities to the spi-qup driver. If DMA channels are
present, the QUP will use DMA instead of block mode for transfers to/from SPI
peripherals for transactions larger than the length of a block.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Reviewed-by: Ivan T. Ivanov <iivanov@mm-sol.com
Signed-off-by: Mark Brown <broonie@kernel.org>
num-cs is 32 bit property, don't read just upper 16 bits.
Fixes: 4a8573abe9 (spi: qup: Remove chip select function)
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch removes a lot of duplicate code since SPI core provides a nice
message handling.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch refactors the code in pump_transfers() to reprogram the registers
immediately when we have a new configuration data. The behaviour is slightly
modified:
- chip is always disabled and reenabled
- CTRL0 is always reprogrammed
This change allows to do a further refactoring and simplier conversion to use
SPI core DMA routines in the future.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The error handling is partially broken since the controller is disabled on
error and is not re-enabled until condition occurs, i.e. mode (poll, PIO/DMA),
chip (cs_change), or speed (clk_div) is changed. In the result of these changes
we will have a predictable state of the SPi controller independently on how
successfull was a previous transfer.
The patch disables interrupts and re-enables the SPI controller wherever it
needs to be done. Thus most of the time the SPI controller is kept enabled. The
runtime PM, when it will be implemented, must take care of the controller
disabling and re-enabling.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit fd316941c ("spi/pl022: disable port when unused") introduced a race,
which leads to possible driver lock up (easily reproducible on SMP).
The problem happens in giveback() function where the completion of the transfer
is signalled to SPI subsystem and then the HW SPI controller is disabled. Another
transfer might be setup in between, which brings driver in locked-up state.
Exact event sequence on SMP:
core0 core1
=> pump_transfers()
/* message->state == STATE_DONE */
=> giveback()
=> spi_finalize_current_message()
=> pl022_unprepare_transfer_hardware()
=> pl022_transfer_one_message
=> flush()
=> do_interrupt_dma_transfer()
=> set_up_next_transfer()
/* Enable SSP, turn on interrupts */
writew((readw(SSP_CR1(pl022->virtbase)) |
SSP_CR1_MASK_SSE), SSP_CR1(pl022->virtbase));
...
=> pl022_interrupt_handler()
=> readwriter()
/* disable the SPI/SSP operation */
=> writew((readw(SSP_CR1(pl022->virtbase)) &
(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
Lockup! SPI controller is disabled and the data will never be received. Whole
SPI subsystem is waiting for transfer ACK and blocked.
So, only signal transfer completion after disabling the controller.
Fixes: fd316941c (spi/pl022: disable port when unused)
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
"flag" variable does nothing, remove it.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
PL022 Programmers model explicitely states "do not modify undefined register
bits". Correct the "all enable" interrupt mask so that it only enables defined
ones.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
According to PL022 specification, TNF bit states for "Transmit FIFO Not full".
So the logic here is inverted. But "Receive Overrun Interrupt", which is handled
here, is only triggered on Rx errors. So instead of fixing the if statement,
remove the whole message.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There was handle_err() callback introduced that is dedicated for error
handling. The patch moves error handling to this callback.
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: linux-rockchip@lists.infradead.org
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This callback would be useful to handle an error that occurs in the generic
implementation of transfer_one_message(). The good candidate for this is to
drain FIFO and / or to terminate DMA transfers when timeout happened.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
