Hi,
This series adds support for octal DTR flashes in the spi-nor framework,
and then adds hooks for the Cypress Semper and Mircom Xcella flashes to
allow running them in octal DTR mode. This series assumes that the flash
is handed to the kernel in Legacy SPI mode.
Tested on TI J721e EVM with 1-bit ECC on the Cypress flash.
Changes in v10:
- Rebase on latest linux-next/master. Drop a couple patches that made it
in the previous release.
- Move the code that sets 20 dummy cycles for MT35XU512ABA to its octal
enable function. This way, if the controller doesn't support 8D mode
20 dummy cycles won't be used.
Changes in v9:
- Do not use '& 0xff' to get the opcode LSB in spi-mxic and
spi-zynq-qspi. The cast to u8 will do that anyway.
- Do not use if (opcode) as a check for whether the command phase exists
in spi-zynq-qspi because the opcode 0 can be valid. Use the new
cmd.nbytes instead.
Changes in v8:
- Move controller changes in spi-mxic to the commit which introduces
2-byte opcodes to avoid problems when bisecting.
- Replace usage of sizeof(op->cmd.opcode) with op->cmd.nbytes.
- Extract opcode in spi-zynq-qspi instead of using &op->cmd.opcode.
Changes in v7:
- Reject ops with more than 1 command byte in
spi_mem_default_supports_op().
- Reject ops with more than 1 command byte in atmel and mtk controllers.
- Reject ops with 0 command bytes in spi_mem_check_op().
- Set cmd.nbytes to 1 when using SPI_MEM_OP_CMD().
- Avoid endianness problems in spi-mxic.
Changes in v6:
- Instead of hard-coding 8D-8D-8D Fast Read dummy cycles to 20, find
them out from the Profile 1.0 table.
Changes in v5:
- Do not enable stateful X-X-X modes if the reset line is broken.
- Instead of setting SNOR_READ_HWCAPS_8_8_8_DTR from Profile 1.0 table
parsing, do it in spi_nor_info_init_params() instead based on the
SPI_NOR_OCTAL_DTR_READ flag instead.
- Set SNOR_HWCAPS_PP_8_8_8_DTR in s28hs post_sfdp hook since this
capability is no longer set in Profile 1.0 parsing.
- Instead of just checking for spi_nor_get_protocol_width() in
spi_nor_octal_dtr_enable(), make sure the protocol is
SNOR_PROTO_8_8_8_DTR since get_protocol_width() only cares about data
width.
- Drop flag SPI_NOR_SOFT_RESET. Instead, discover soft reset capability
via BFPT.
- Do not make an invalid Quad Enable BFPT field a fatal error. Silently
ignore it by assuming no quad enable bit is present.
- Set dummy cycles for Cypress Semper flash to 24 instead of 20. This
allows for 200MHz operation in 8D mode compared to the 166MHz with 20.
- Rename spi_nor_cypress_octal_enable() to
spi_nor_cypress_octal_dtr_enable().
- Update spi-mtk-nor.c to reject DTR ops since it doesn't call
spi_mem_default_supports_op().
Changes in v4:
- Refactor the series to use the new spi-nor framework with the
manufacturer-specific bits separated from the core.
- Add support for Micron MT35XU512ABA.
- Use cmd.nbytes as the criteria of whether the data phase exists or not
instead of cmd.buf.in || cmd.buf.out in spi_nor_spimem_setup_op().
- Update Read FSR to use the same dummy cycles and address width as Read
SR.
- Fix BFPT parsing stopping too early for JESD216 rev B flashes.
- Use 2 byte reads for Read SR and FSR commands in DTR mode.
Changes in v3:
- Drop the DT properties "spi-rx-dtr" and "spi-tx-dtr". Instead, if
later a need is felt to disable DTR in case someone has a board with
Octal DTR capable flash but does not support DTR transactions for some
reason, a property like "spi-no-dtr" can be added.
- Remove mode bits SPI_RX_DTR and SPI_TX_DTR.
- Remove the Cadence Quadspi controller patch to un-block this series. I
will submit it as a separate patch.
- Rebase on latest 'master' and fix merge conflicts.
- Update read and write dirmap templates to use DTR.
- Rename 'is_dtr' to 'dtr'.
- Make 'dtr' a bitfield.
- Reject DTR ops in spi_mem_default_supports_op().
- Update atmel-quadspi to reject DTR ops. All other controller drivers
call spi_mem_default_supports_op() so they will automatically reject
DTR ops.
- Add support for both enabling and disabling DTR modes.
- Perform a Software Reset on flashes that support it when shutting
down.
- Disable Octal DTR mode on suspend, and re-enable it on resume.
- Drop enum 'spi_mem_cmd_ext' and make command opcode u16 instead.
Update spi-nor to use the 2-byte command instead of the command
extension. Since we still need a "extension type", mode that enum to
spi-nor and name it 'spi_nor_cmd_ext'.
- Default variable address width to 3 to fix SMPT parsing.
- Drop non-volatile change to uniform sector mode and rely on parsing
SMPT.
Changes in v2:
- Add DT properties "spi-rx-dtr" and "spi-tx-dtr" to allow expressing
DTR capabilities.
- Set the mode bits SPI_RX_DTR and SPI_TX_DTR when we discover the DT
properties "spi-rx-dtr" and spi-tx-dtr".
- spi_nor_cypress_octal_enable() was updating nor->params.read[] with
the intention of setting the correct number of dummy cycles. But this
function is called _after_ selecting the read so setting
nor->params.read[] will have no effect. So, update nor->read_dummy
directly.
- Fix spi_nor_spimem_check_readop() and spi_nor_spimem_check_pp()
passing nor->read_proto and nor->write_proto to
spi_nor_spimem_setup_op() instead of read->proto and pp->proto
respectively.
- Move the call to cqspi_setup_opcode_ext() inside cqspi_enable_dtr().
This avoids repeating the 'if (f_pdata->is_dtr)
cqspi_setup_opcode_ext()...` snippet multiple times.
- Call the default 'supports_op()' from cqspi_supports_mem_op(). This
makes sure the buswidth requirements are also enforced along with the
DTR requirements.
- Drop the 'is_dtr' argument from spi_check_dtr_req(). We only call it
when a phase is DTR so it is redundant.
Pratyush Yadav (17):
spi: spi-mem: allow specifying whether an op is DTR or not
spi: spi-mem: allow specifying a command's extension
spi: atmel-quadspi: reject DTR ops
spi: spi-mtk-nor: reject DTR ops
mtd: spi-nor: add support for DTR protocol
mtd: spi-nor: sfdp: get command opcode extension type from BFPT
mtd: spi-nor: sfdp: parse xSPI Profile 1.0 table
mtd: spi-nor: core: use dummy cycle and address width info from SFDP
mtd: spi-nor: core: do 2 byte reads for SR and FSR in DTR mode
mtd: spi-nor: core: enable octal DTR mode when possible
mtd: spi-nor: sfdp: do not make invalid quad enable fatal
mtd: spi-nor: sfdp: detect Soft Reset sequence support from BFPT
mtd: spi-nor: core: perform a Soft Reset on shutdown
mtd: spi-nor: core: disable Octal DTR mode on suspend.
mtd: spi-nor: core: expose spi_nor_default_setup() in core.h
mtd: spi-nor: spansion: add support for Cypress Semper flash
mtd: spi-nor: micron-st: allow using MT35XU512ABA in Octal DTR mode
drivers/mtd/spi-nor/core.c | 446 +++++++++++++++++++++++++++-----
drivers/mtd/spi-nor/core.h | 22 ++
drivers/mtd/spi-nor/micron-st.c | 103 +++++++-
drivers/mtd/spi-nor/sfdp.c | 131 +++++++++-
drivers/mtd/spi-nor/sfdp.h | 8 +
drivers/mtd/spi-nor/spansion.c | 166 ++++++++++++
drivers/spi/atmel-quadspi.c | 6 +
drivers/spi/spi-mem.c | 16 +-
drivers/spi/spi-mtk-nor.c | 10 +-
drivers/spi/spi-mxic.c | 3 +-
drivers/spi/spi-zynq-qspi.c | 11 +-
include/linux/mtd/spi-nor.h | 53 +++-
include/linux/spi/spi-mem.h | 14 +-
13 files changed, 889 insertions(+), 100 deletions(-)
--
2.27.0
base-commit: b3a9e3b962
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
In xSPI mode, flashes expect 2-byte opcodes. The second byte is called
the "command extension". There can be 3 types of extensions in xSPI:
repeat, invert, and hex. When the extension type is "repeat", the same
opcode is sent twice. When it is "invert", the second byte is the
inverse of the opcode. When it is "hex" an additional opcode byte based
is sent with the command whose value can be anything.
So, make opcode a 16-bit value and add a 'nbytes', similar to how
multiple address widths are handled.
Some places use sizeof(op->cmd.opcode). Replace them with op->cmd.nbytes
The spi-mxic and spi-zynq-qspi drivers directly use op->cmd.opcode as a
buffer. Now that opcode is a 2-byte field, this can result in different
behaviour depending on if the machine is little endian or big endian.
Extract the opcode in a local 1-byte variable and use that as the buffer
instead. Both these drivers would reject multi-byte opcodes in their
supports_op() hook anyway, so we only need to worry about single-byte
opcodes for now.
The above two changes are put in this commit to keep the series
bisectable.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20200623183030.26591-3-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Each phase is given a separate 'dtr' field so mixed protocols like
4S-4D-4D can be supported.
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20200623183030.26591-2-p.yadav@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Use kthread_create_worker() helper to simplify the code. It uses
the kthread worker API the right way. It will eventually allow
to remove the FIXME in kthread_worker_fn() and add more consistency
checks in the future.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200709065007.26896-1-m.szyprowski@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
On some SPI controllers (like spi-geni-qcom) setting the chip select
is a heavy operation. For instance on spi-geni-qcom, with the current
code, is was measured as taking upwards of 20 us. Even on SPI
controllers that aren't as heavy, setting the chip select is at least
something like a MMIO operation over some peripheral bus which isn't
as fast as a RAM access.
While it would be good to find ways to mitigate problems like this in
the drivers for those SPI controllers, it can also be noted that the
SPI framework could also help out. Specifically, in some situations,
we can see the SPI framework calling the driver's set_cs() with the
same parameter several times in a row. This is specifically observed
when looking at the way the Chrome OS EC SPI driver (cros_ec_spi)
works but other drivers likely trip it to some extent.
Let's solve this by caching the chip select state in the core and only
calling into the controller if there was a change. We check not only
the "enable" state but also the chip select mode (active high or
active low) since controllers may care about both the mode and the
enable flag in their callback.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200629164103.1.Ied8e8ad8bbb2df7f947e3bc5ea1c315e041785a2@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
Add fallback to pio mode in case dma transfer failed with error status
SPI_TRANS_FAIL_NO_START.
If spi client driver want to enable this feature please set xfer->error in
the proper place such as dmaengine_prep_slave_sg() failure detect(but no
any data put into spi bus yet). Besides, add master->fallback checking in
its can_dma() so that spi core could switch to pio next time. Please refer
to spi-imx.c.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Link: https://lore.kernel.org/r/1592347329-28363-2-git-send-email-yibin.gong@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch introduces platform data for slave information, it allows
spi-altera to add new spi devices once master registration is done.
Signed-off-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/1591845911-10197-4-git-send-email-yilun.xu@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch introduced SPI core parameters in platform data, it
allows passing these SPI core parameters via platform data.
Signed-off-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/1591845911-10197-3-git-send-email-yilun.xu@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
kernel cycle.
New drivers:
- Intel Jasper Lake support.
- NXP Freescale i.MX8DXL support.
- Qualcomm SM8250 support.
- Renesas R8A7742 SH-PFC support.
Driver improvements:
- Severe cleanup and modernization of the MCP23s08 driver.
- Mediatek driver modularized.
- Setting config supported in the Meson driver.
- Wakeup support for the Broadcom BCM7211.
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Merge tag 'pinctrl-v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"This is the bulk of pin control changes for the v5.8 kernel cycle.
It's just really boring this time. Zero core changes. Just linear
development, cleanups and misc noncritical fixes. Some new drivers for
very new Qualcomm and Intel chips.
New drivers:
- Intel Jasper Lake support.
- NXP Freescale i.MX8DXL support.
- Qualcomm SM8250 support.
- Renesas R8A7742 SH-PFC support.
Driver improvements:
- Severe cleanup and modernization of the MCP23s08 driver.
- Mediatek driver modularized.
- Setting config supported in the Meson driver.
- Wakeup support for the Broadcom BCM7211"
* tag 'pinctrl-v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (72 commits)
pinctrl: sprd: Fix the incorrect pull-up definition
pinctrl: pxa: pxa2xx: Remove 'pxa2xx_pinctrl_exit()' which is unused and broken
pinctrl: freescale: imx: Use 'devm_of_iomap()' to avoid a resource leak in case of error in 'imx_pinctrl_probe()'
pinctrl: freescale: imx: Fix an error handling path in 'imx_pinctrl_probe()'
pinctrl: sirf: add missing put_device() call in sirfsoc_gpio_probe()
pinctrl: imxl: Fix an error handling path in 'imx1_pinctrl_core_probe()'
pinctrl: bcm2835: Add support for wake-up interrupts
pinctrl: bcm2835: Match BCM7211 compatible string
dt-bindings: pinctrl: Document optional BCM7211 wake-up interrupts
dt-bindings: pinctrl: Document 7211 compatible for brcm, bcm2835-gpio.txt
dt-bindings: pinctrl: stm32: Add missing interrupts property
pinctrl: at91-pio4: Add COMPILE_TEST support
pinctrl: Fix return value about devm_platform_ioremap_resource()
MAINTAINERS: Renesas Pin Controllers are supported
dt-bindings: pinctrl: ocelot: Add Sparx5 SoC support
pinctrl: ocelot: Fix GPIO interrupt decoding on Jaguar2
pinctrl: ocelot: Remove instance number from pin functions
pinctrl: ocelot: Always register GPIO driver
dt-bindings: pinctrl: rockchip: update example
pinctrl: amd: Add ACPI dependency
...
- Add backlight_device_get_by_name() to the API
- New Device Support
- Add support for WLED5 to Qualcomm WLED
- Fix-ups
- Convert to GPIO descriptors; l4f00242t03
- Device Tree fix-ups; qcom-wled
- Bug Fixes
- Properly disable regulators on .probe() failure
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Merge tag 'backlight-next-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"Core Framework:
- Add backlight_device_get_by_name() to the API
New Device Support:
- Add support for WLED5 to Qualcomm WLED
Fix-ups:
- Convert to GPIO descriptors in l4f00242t03
- Device Tree fix-ups for qcom-wled
Bug Fixes:
- Properly disable regulators on .probe() failure"
* tag 'backlight-next-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: Add backlight_device_get_by_name()
backlight: qcom-wled: Add support for WLED5 peripheral that is present on PM8150L PMICs
dt-bindings: backlight: qcom-wled: Add WLED5 bindings
backlight: qcom-wled: Add callback functions
dt-bindings: backlight: qcom-wled: Convert the wled bindings to .yaml format
backlight: l4f00242t03: Convert to GPIO descriptors
backlight: lp855x: Ensure regulators are disabled on probe failure
This converts the l4f00242t03 backlight driver to use GPIO
descriptors and switches the two Freescale i.MX boards over
to passing descriptors instead of global GPIO numbers.
We use the typical names "enable" and "reset" as found in
the device tree bindings for panel GPIOs.
This saves a lot of code in the driver and makes it possible
to get rid of the platform data header altogether.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Platform data is a legacy interface to supply device properties
to the driver. In this case we even don't have in-kernel users
for it. Just remove it for good.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200407173849.43628-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
- Switch to GPIO descriptor; pwm_bl, corgi_lcd
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Merge tag 'backlight-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"Switch pwm_bl and corgi_lcd drivers to use GPIO descriptors"
* tag 'backlight-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: corgi: Convert to use GPIO descriptors
backlight: pwm_bl: Switch to full GPIO descriptor
Here is the big set of TTY / Serial patches for 5.7-rc1
Lots of console fixups and reworking in here, serial core tweaks
(doesn't that ever get old, why are we still creating new serial
devices?), serial driver updates, line-protocol driver updates, and some
vt cleanups and fixes included in here as well.
All have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial updates from Greg KH:
"Here is the big set of TTY / Serial patches for 5.7-rc1
Lots of console fixups and reworking in here, serial core tweaks
(doesn't that ever get old, why are we still creating new serial
devices?), serial driver updates, line-protocol driver updates, and
some vt cleanups and fixes included in here as well.
All have been in linux-next with no reported issues"
* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
serial: 8250: Optimize irq enable after console write
serial: 8250: Fix rs485 delay after console write
vt: vt_ioctl: fix use-after-free in vt_in_use()
vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
tty: serial: make SERIAL_SPRD depend on COMMON_CLK
tty: serial: fsl_lpuart: fix return value checking
tty: serial: fsl_lpuart: move dma_request_chan()
ARM: dts: tango4: Make /serial compatible with ns16550a
ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
ARM: dts: mmp*: Fix serial port names
ARM: dts: mmp2-brownstone: Don't redeclare phandle references
ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
ARM: dts: pxa*: Fix serial port names
ARM: dts: pxa*: Don't redeclare phandle references
serial: omap: drop unused dt-bindings header
serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
serial: 8250: 8250_omap: Account for data in flight during DMA teardown
...
The code in the Corgi backlight driver can be considerably
simplified by moving to GPIO descriptors and lookup tables
from the board files instead of passing GPIO numbers using
the old API.
Make sure to encode inversion semantics for the Akita and
Spitz platforms inside the GPIO lookup table and drop the
custom inversion semantics from the driver.
All in-tree users are converted in this patch.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
This driver for the Intel MID never seems to have been properly
integrated upstream: the platform data in <linux/spi/ifx_modem.h>
is not used anywhere in the kernel and haven't been since it was
merged into the kernel in 2010.
There might be out-of-tree users, so I don't want to delete the
driver, but I will refactor it to use GPIO descriptors, which
means that out-of-tree users will need to adapt.
There are several examples in the kernel of how to provide the
resources necessary for using GPIO descriptors to pass in the
GPIO lines, for the MID platform in particular, it will suffice
to inspect the code in files like:
arch/x86/platform/intel-mid/device_libs/platform_bt.c
This refactoring transfers all GPIOs in the driver, including
a hard-coded "PMU reset" in the driver to use GPIO descriptors
instead.
The following named GPIO descriptors need to be supplied:
- reset
- power
- mrdy
- srdy
- rst_out
- pmu_reset
Cc: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200311083131.693908-2-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When dealing with a SPI controller driver that is sending more than 1
byte at once (or the entire buffer at once), and the SPI peripheral
driver has requested timestamping for a byte in the middle of the
buffer, we find that spi_take_timestamp_pre never records a "pre"
timestamp.
This happens because the function currently expects to be called with
the "progress" argument >= to what the peripheral has requested to be
timestamped. But clearly there are cases when that isn't going to fly.
And since we can't change the past when we realize that the opportunity
to take a "pre" timestamp has just passed and there isn't going to be
another one, the approach taken is to keep recording the "pre" timestamp
on each call, overwriting the previously recorded one until the "post"
timestamp is also taken.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-8-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently ACPI firmware description for a SPI device does not have any
method to describe the data buswidth on the board.
So even through the controller and device may support higher modes than
standard SPI, it cannot be assumed that the board does - as such, that
device is limited to standard SPI in such a circumstance.
As a workaround, allow the controller driver supply buswidth override bits,
which are used inform the core code that the controller driver knows the
buswidth supported on that board for that device.
A host controller driver might know this info from DMI tables, for example.
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1582903131-160033-2-git-send-email-john.garry@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Some SPI master controllers always drive a native chip select when
performing a transfer. Hence when using both native and GPIO chip
selects, at least one native chip select must be left unused, to be
driven when performing transfers with slave devices using GPIO chip
selects.
Currently, to find an unused native chip select, SPI controller drivers
need to parse and process cs-gpios theirselves. This is not only
duplicated in each driver that needs it, but also duplicates part of the
work done later at SPI controller registration time. Note that this
cannot be done after spi_register_controller() returns, as at that time,
slave devices may have been probed already.
Hence add generic support to the SPI subsystem for finding an unused
native chip select. Optionally, this unused native chip select, and all
other in-use native chip selects, can be validated against the maximum
number of native chip selects available on the controller hardware.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200102133822.29346-2-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
The API for PTP system timestamping (associating a SPI transaction with
the system time at which it was transferred) is flawed: it assumes that
the xfer->tx_buf pointer will always be present.
This is, of course, not always the case.
So introduce a "progress" variable that denotes how many word have been
transferred.
Fix the Freescale DSPI driver, the only user of the API so far, in the
same patch.
Fixes: b42faeee71 ("spi: Add a PTP system timestamp to the transfer structure")
Fixes: d6b71dfaee ("spi: spi-fsl-dspi: Implement the PTP system timestamping for TCFQ mode")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20191227012417.1057-1-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Switch the OC Tiny driver over to handling CS GPIOs using
GPIO descriptors in the core.
This driver is entirely relying on GPIOs to be used for
chipselect, so let the core pick these out using either
device tree or machine descriptors.
There are no in-tree users of this driver so no board files
need to be patched, out-of-tree boardfiles can use machine
descriptor tables, c.f. commit 1dfbf334f1.
Cc: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20191205092411.64341-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
This change documents the CS setup, host & inactive times. They were
omitted when the fields were added, and were caught by one of the build
bots.
Fixes: 25093bdeb6 ("spi: implement SW control for CS times")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20191023070046.12478-1-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The way the max delay is computed for this controller, it looks like it is
searching for the max delay from an SPI message a using that.
No idea if this is valid. But this change should support both `delay_usecs`
and the new `delay` data which is of `spi_delay` type.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-17-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This change implements CS control for setup, hold & inactive delays.
The `cs_setup` delay is completely new, and can help with cases where
asserting the CS, also brings the device out of power-sleep, where there
needs to be a longer (than usual), before transferring data.
The `cs_hold` time can overlap with the `delay` (or `delay_usecs`) from an
SPI transfer. The main difference is that `cs_hold` implies that CS will be
de-asserted.
The `cs_inactive` delay does not have a clear use-case yet. It has been
implemented mostly because the `spi_set_cs_timing()` function implements
it. To some degree, this could overlap or replace `cs_change_delay`, but
this will require more consideration/investigation in the future.
All these delays have been added to the `spi_controller` struct, as they
would typically be configured by calling `spi_set_cs_timing()` after an
`spi_setup()` call.
Software-mode for CS control, implies that the `set_cs_timing()` hook has
not been provided for the `spi_controller` object.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-16-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The initial version of `spi_set_cs_timing()` was implemented with
consideration only for clock-cycles as delay.
For cases like `CS setup` time, it's sometimes needed that micro-seconds
(or nano-seconds) are required, or sometimes even longer delays, for cases
where the device needs a little longer to start transferring that after CS
is asserted.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-15-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The change introduces the `delay` field to the `spi_transfer` struct as an
`struct spi_delay` type.
This intends to eventually replace `delay_usecs`.
But, since there are many users of `delay_usecs`, this needs some
intermediate work.
A helper called `spi_transfer_delay_exec()` is also added, which maintains
backwards compatibility with `delay_usecs`, by assigning the value to
`delay` if non-zero.
This should maintain backwards compatibility with current users of
`udelay_usecs`.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-9-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This change does a conversion from the `word_delay_usecs` -> `word_delay`
for the `spi_device` struct.
This allows users to specify inter-word delays in other unit types
(nano-seconds or clock cycles), depending on how users want.
The Atmel SPI driver is the only current user of the `word_delay_usecs`
field (from the `spi_device` struct).
So, it needed a slight conversion to use the `word_delay` as an `spi_delay`
struct.
In SPI core, the only required mechanism is to update the `word_delay`
information per `spi_transfer`. This requires a bit more logic than before,
because it needs that both delays be converted to a common unit
(nano-seconds) for comparison.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-8-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The Spreadtrum SPI driver is the only user of the `word_delay` field in
the `spi_transfer` struct.
This change converts the field to use the `spi_delay` struct. This also
enforces the users to specify the delay unit to be `SPI_DELAY_UNIT_SCK`.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-5-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Since the logic for `spi_delay` struct + `spi_delay_exec()` has been copied
from the `cs_change_delay` logic, it's natural to make this delay, the
first user.
The `cs_change_delay` logic requires that the default remain 10 uS, in case
it is unspecified/unconfigured. So, there is some special handling needed
to do that.
The ADIS library is one of the few users of the new `cs_change_delay`
parameter for an spi_transfer.
The introduction of the `spi_delay` struct, requires that the users of of
`cs_change_delay` get an update. This change also updates the ADIS library.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-4-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
There are plenty of delays that have been introduced in SPI core. Most of
them are in micro-seconds, some need to be in nano-seconds, and some in
clock-cycles.
For some of these delays (related to transfers & CS timing) it may make
sense to have a `spi_delay` struct that abstracts these a bit.
The important element of these delays [for unification] seems to be the
`unit` of the delay.
It looks like micro-seconds is good enough for most people, but every-once
in a while, some delays seem to require other units of measurement.
This change adds the `spi_delay` struct & a `spi_delay_exec()` function
that processes a `spi_delay` object/struct to execute the delay.
It's a copy of the `cs_change_delay` mechanism, but without the default
for 10 uS.
The clock-cycle delay unit is a bit special, as it needs to be bound to an
`spi_transfer` object to execute.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-3-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI is one of the interfaces used to access devices which have a POSIX
clock driver (real time clocks, 1588 timers etc). The fact that the SPI
bus is slow is not what the main problem is, but rather the fact that
drivers don't take a constant amount of time in transferring data over
SPI. When there is a high delay in the readout of time, there will be
uncertainty in the value that has been read out of the peripheral.
When that delay is constant, the uncertainty can at least be
approximated with a certain accuracy which is fine more often than not.
Timing jitter occurs all over in the kernel code, and is mainly caused
by having to let go of the CPU for various reasons such as preemption,
servicing interrupts, going to sleep, etc. Another major reason is CPU
dynamic frequency scaling.
It turns out that the problem of retrieving time from a SPI peripheral
with high accuracy can be solved by the use of "PTP system
timestamping" - a mechanism to correlate the time when the device has
snapshotted its internal time counter with the Linux system time at that
same moment. This is sufficient for having a precise time measurement -
it is not necessary for the whole SPI transfer to be transmitted "as
fast as possible", or "as low-jitter as possible". The system has to be
low-jitter for a very short amount of time to be effective.
This patch introduces a PTP system timestamping mechanism in struct
spi_transfer. This is to be used by SPI device drivers when they need to
know the exact time at which the underlying device's time was
snapshotted. More often than not, SPI peripherals have a very exact
timing for when their SPI-to-interconnect bridge issues a transaction
for snapshotting and reading the time register, and that will be
dependent on when the SPI-to-interconnect bridge figures out that this
is what it should do, aka as soon as it sees byte N of the SPI transfer.
Since spi_device drivers are the ones who'd know best how the peripheral
behaves in this regard, expose a mechanism in spi_transfer which allows
them to specify which word (or word range) from the transfer should be
timestamped.
Add a default implementation of the PTP system timestamping in the SPI
core. This is not going to be satisfactory performance-wise, but should
at least increase the likelihood that SPI device drivers will use PTP
system timestamping in the future.
There are 3 entry points from the core towards the SPI controller
drivers:
- transfer_one: The driver is passed individual spi_transfers to
execute. This is the easiest to timestamp.
- transfer_one_message: The core passes the driver an entire spi_message
(a potential batch of spi_transfers). The core puts the same pre and
post timestamp to all transfers within a message. This is not ideal,
but nothing better can be done by default anyway, since the core has
no insight into how the driver batches the transfers.
- transfer: Like transfer_one_message, but for unqueued drivers (i.e.
the driver implements its own queue scheduling).
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190905010114.26718-3-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Compiler is not happy about spi_set_cs_timing() prototype.
drivers/spi/spi.c:3016:6: warning: no previous prototype for ‘spi_set_cs_timing’ [-Wmissing-prototypes]
void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold,
^~~~~~~~~~~~~~~~~
Let's add it to the header.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license this program
is distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 100 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.918357685@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 655 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Right now the only way to get the SPI pumping thread bumped up to
realtime priority is for the controller to request it. However it may
be that the controller works fine with the normal priority but
communication to a particular SPI device on the bus needs realtime
priority.
Let's add a way for devices to request realtime priority when they set
themselves up.
NOTE: this will just affect the priority of transfers that end up on
the SPI core's pumping thread. In many cases transfers happen in the
context of the caller so if you need realtime priority for all
transfers you should ensure the calling context is also realtime
priority.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Provide a means for the spi bus driver to report the effectively used
spi clock frequency used for each spi_transfer.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Support setting a delay between cs assert and deassert as
a multiple of spi clock length.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
For some SPI devices that support speed_hz > 1MHz the default 10 us delay
when cs_change = 1 is typically way to long and may result in poor spi bus
utilization.
This patch makes it possible to control the delay at micro or nano second
resolution on a per spi_transfer basis. It even allows an "as fast as
possible" mode with:
xfer.cs_change_delay_unit = SPI_DELAY_UNIT_NSECS;
xfer.cs_change_delay = 0;
The delay code is shared between delay_usecs and cs_change_delay for
consistency and reuse, so in the future this change_delay_unit could also
apply to delay_usec as well.
Note that on slower SOCs/CPU actually reaching ns deasserts on cs is not
realistic as the gpio overhead alone (without any delays added ) may
already leave cs deasserted for more than 1us - at least on a raspberry pi.
But at the very least this way we can keep it as short as possible.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Colton Lewis