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RSPI IP on RZ/{A, G2L} SoC's has the same signal for both interrupt
and DMA transfer request. Setting DMARS register for DMA transfer
makes the signal to work as a DMA transfer request signal and
subsequent interrupt requests to the interrupt controller
are masked.
PIO fallback does not work as interrupt signal is disabled.
This patch fixes this issue by re-enabling the interrupts by
calling dmaengine_synchronize().
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220721143449.879257-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Fix SPI NO Slave Select macro definition, when all the SPI CS bits
are high which means no slave is selected.
Fixes: 21b511ddee09 ("spi: spi-cadence: Fix SPI CS gets toggling sporadically")
Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
Link: https://lore.kernel.org/r/20220713164529.28444-1-amit.kumar-mahapatra@xilinx.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Adding FIU NPCM8XX support to NPCM FIU driver.
NPCM8XX FIU supports four controllers.
As part of adding NPCM8XX support:
- Add NPCM8XX specific compatible string.
- Using an internal burst configuration register instead of a GCR
register.
- Support FIU1 controller.
Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20220718081146.256070-4-tmaimon77@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Modify NPCM BMC FIU direct read dummy configuration that according
spi-mem direct read function.
Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20220718081146.256070-2-tmaimon77@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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In case a IRQ based transfer times out the bcm2835_spi_handle_err()
function is called. Since commit 1513ceee70f2 ("spi: bcm2835: Drop
dma_pending flag") the TX and RX DMA transfers are unconditionally
canceled, leading to NULL pointer derefs if ctlr->dma_tx or
ctlr->dma_rx are not set.
Fix the NULL pointer deref by checking that ctlr->dma_tx and
ctlr->dma_rx are valid pointers before accessing them.
Fixes: 1513ceee70f2 ("spi: bcm2835: Drop dma_pending flag")
Cc: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220719072234.2782764-1-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
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Remove #ifdef CONFIG_PM, #ifdef CONFIG_PM_SLEEP and use
SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS() macros instead which allows
getting also rid of __maybe_unused in the code.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220718071052.1707858-1-claudiu.beznea@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Currently the spi_master is allocated by devm_spi_alloc_master()
and devres core manages the deallocation, but in probe failure
path spi_master_put() is being handled manually which causes
"refcount underflow use-after-free" warning when probe failure happens
after allocating spi_master.
Trimmed backtrace during failure:
refcount_t: underflow; use-after-free.
pc : refcount_warn_saturate+0xf4/0x144
Call trace:
refcount_warn_saturate
kobject_put
put_device
devm_spi_release_controller
devres_release_all
This commit makes relevant changes to remove spi_master_put() from probe
failure path.
Fixes: 606e5d408184 ("spi: cadence-quadspi: Handle spi_unregister_master() in remove()")
Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Link: https://lore.kernel.org/r/20220601071611.11853-1-vaishnav.a@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Merge series from nandhini.srikandan@intel.com <nandhini.srikandan@intel.com>:
This patch enables support for DW SPI on Intel Thunder Bay. This patch
set also enables master mode for latest Designware SPI versions. The
driver is tested on Keem Bay and Thunder Bay evaluation board.
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Merge series from Yang Yingliang <yangyingliang@huawei.com>:
Patch #1 fix a UAF in mchp_corespi_remove().
Patch #2 and #3 some cleanups to simpify code.
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After calling spi_unregister_master(), the refcount of master will
be decrease to 0, and it will be freed in spi_controller_release(),
the device data also will be freed, so it will lead a UAF when using
'tspi'. To fix this, get the master before unregister and put it when
finish using it.
Fixes: 26c863418221 ("spi: tegra20-slink: Don't use resource-managed spi_register helper")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220713094024.1508869-1-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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This reverts commit 59ebbe40fb51 ("spi: simplify
devm_spi_register_controller").
If devm_add_action() fails in devm_add_action_or_reset(),
devm_spi_unregister() will be called, it decreases the
refcount of 'ctlr->dev' to 0, then it will cause uaf in
the drivers that calling spi_put_controller() in error path.
Fixes: 59ebbe40fb51 ("spi: simplify devm_spi_register_controller")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220712135504.1055688-1-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Switch to use dev_err_probe() to simpify error path.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-4-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Switch to use devm_spi_alloc_master() to simpify error path.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-3-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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When using devm_spi_register_master(), the unregister function will
be called in devres_release_all() which is called after ->remove(),
so remove spi_unregister_master() andspi_master_put().
Fixes: 9ac8d17694b6 ("spi: add support for microchip fpga spi controllers")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-2-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add support for Intel Thunder Bay SPI controller, which uses DesignWare
DWC_ssi core and also add common init function for both Keem Bay and
Thunder Bay.
Signed-off-by: Nandhini Srikandan <nandhini.srikandan@intel.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20220713042223.1458-5-nandhini.srikandan@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add support to select the controller mode as master mode by setting Bit 31
of CTRLR0 register. This feature is supported for controller versions above
v1.02.
Signed-off-by: Nandhini Srikandan <nandhini.srikandan@intel.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20220713042223.1458-4-nandhini.srikandan@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add the missing underscore in IP version macro to avoid compilation issue.
The macro is used for IP version comparison in the current patchset.
Fixes: 2cc8d9227bbb ("spi: dw: Introduce Synopsys IP-core versions interface")
Signed-off-by: Nandhini Srikandan <nandhini.srikandan@intel.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20220713042223.1458-2-nandhini.srikandan@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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This pull request contains Broadcom SoC drivers updatse for 5.20, please
pull the following:
- Julia fixes a typo in the Broadcom STB legacy power management code
- Liang fixes a device_node reference count leak in the Broadcom STB BIU
driver code error path(s)
- Nicolas and Stefan provide updates to the BCM2835 power management
driver allowing its use on BCM2711 (Raspberry Pi 4) and to enable the
use of the V3D GPU driver on such platforms. This is a merge of an
immutable branch from Lee Jones' MFD tree
- William removes the use of CONFIG_ARCH_BCM_63XX which is removed and
replaces the dependencies with CONFIG_ARCH_BCMBCA which is how all of
the DSL/PON SoCs from Broadcom are now supported in the upstream
kernel.
* tag 'arm-soc/for-5.20/drivers' of https://github.com/Broadcom/stblinux:
tty: serial: bcm63xx: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
spi: bcm63xx-hsspi: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
clk: bcm: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
hwrng: bcm2835: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
phy: brcm-sata: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
i2c: brcmstb: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
ata: ahci_brcm: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
soc: bcm: bcm2835-power: Bypass power_on/off() calls
soc: bcm: bcm2835-power: Add support for BCM2711's RPiVid ASB
soc: bcm: bcm2835-power: Resolve ASB register macros
soc: bcm: bcm2835-power: Refactor ASB control
mfd: bcm2835-pm: Add support for BCM2711
mfd: bcm2835-pm: Use 'reg-names' to get resources
soc: bcm: brcmstb: biuctrl: Add missing of_node_put()
soc: bcm: brcmstb: pm: pm-arm: fix typo in comment
Link: https://lore.kernel.org/r/20220711164451.3542127-6-f.fainelli@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Prepare for the BCM63138 ARCH_BCM_63XX migration to ARCH_BCMBCA. Make
SPI_BCM63XX_HSSPI depending on ARCH_BCMBCA.
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
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The acpi_spi_add_resource() is never called with ctrl == NULL and
index == -1. The only caller already performs the check. Hence
remove the duplication from the acpi_spi_add_resource().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220709000709.35622-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Since acpi_spi_device_alloc() has been designed to return an error
pointer we may now properly propagate error codes to the caller of
it. It helps debugging a lot.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220709000709.35622-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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If the controller is not available, it might be in the future and
we would like to re-probe the peripheral again. For that purpose
return deferred probe.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215993
Fixes: 87e59b36e5e2 ("spi: Support selection of the index of the ACPI Spi Resource before alloc")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220709212956.25530-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Work around problems with large transfers.
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Merge series from Cristian Ciocaltea <cristian.ciocaltea@collabora.com>:
This patch series addresses an issue in the spi-amd driver and, while
there, performs some additional cleanups, like simplifying the error
handling in the probe function and removing an unused struct member.
For improving code readability, it also adds some kernel-doc comments.
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Provide documentation comments in the kernel-doc format
for enum amd_spi_versions and struct amd_spi.
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-6-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The io_base_addr member of struct amd_spi is not referenced anywhere
in the driver implementation and there is no indication that it could
be used in the future, hence drop it.
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-5-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Simplify the error handling in probe function by switching from
dev_err() to dev_err_probe().
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-4-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Make use of the devm variant of spi_alloc_master() in order to cleanup
and simplify the error handling in the probe function by getting rid
of the goto statements.
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-3-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Enabling the SPI CS35L41 audio codec driver for Steam Deck [1]
revealed a problem with the current AMD SPI controller driver
implementation, consisting of an unrecoverable system hang.
The issue can be prevented if we ensure the max transfer size
and the max message size do not exceed the FIFO buffer size.
According to the implementation of the downstream driver, the
AMD SPI controller is not able to handle more than 70 bytes per
transfer, which corresponds to the size of the FIFO buffer.
Hence, let's fix this by setting the SPI limits mentioned above.
[1] https://lore.kernel.org/r/20220621213819.262537-1-cristian.ciocaltea@collabora.com
Reported-by: Anastasios Vacharakis <vacharakis@o2mail.de>
Fixes: bbb336f39efc ("spi: spi-amd: Add AMD SPI controller driver support")
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-2-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Merge series from David Jander <david@protonic.nl>:
This series fixes some coding style issues. No functional change.
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Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220629142519.3985486-4-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Capitalize first word in comment where appropriate and add
parentheses to function names.
Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220629142519.3985486-3-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220629142519.3985486-2-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add support for LPSS SPI on Intel Meteor Lake-P. It has three
controllers each having two chip selects.
This squashes a fix from Ap, Kamal <kamal.ap@intel.com> fixing incorrect
PCI ID of 3rd controller.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220630073305.632850-1-jarkko.nikula@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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When using the normal read operation for data transfers, the dummy bus
width is zero. In that case, they are no dummy bytes to transfer and
setting the dummy field in the controller register becomes useless.
Issue was found on a custom "Bifrost" board based on the AST2500 SoC
and using a MX25L51245GMI-08G SPI Flash.
Reported-by: Ian Woloschin <ian.woloschin@akamai.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Tested-by: Ian Woloschin <iwolosch@akamai.com>
Fixes: 9da06d7bdec7dad80 ("spi: aspeed: Add support for direct mapping")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Link: https://lore.kernel.org/r/20220622161617.3719096-3-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
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The default value of the control register is set using the direct
mapping information passed to the ->dirmap_create() handler. Dump the
mapping range and the SPI memory operation characteristics to analyze
how the register value has been computed.
spi-aspeed-smc 1e630000.spi: CE0 read dirmap [ 0x00000000 - 0x04000000 ] OP 0x6c mode:1.1.1.4 naddr:0x4 ndummies:0x1
...
spi-aspeed-smc 1e630000.spi: CE0 write dirmap [ 0x00000000 - 0x04000000 ] OP 0x12 mode:1.1.0.1 naddr:0x4 ndummies:0x0
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20220622161617.3719096-2-clg@kaod.org
Signed-off-by: Mark Brown <broonie@kernel.org>
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Merge series from Chanho Park <chanho61.park@samsung.com>:
Add to support Exynos Auto v9 SoC's spi. By supporting USI(Universal
Serial Interface) mode, the SoC can support up to 12 spi ports. Thus, we
need to increase MAX_SPI_PORTS from 6 to 12. The spi of the SoC can
support loopback mode unlike previous exynos SoCs. To separate the
feature, we need to add .has_loopback to the s3c64xx_spi_port_config.
Furthermore, it uses 4 as the default internal clock divider. We also
need to clk_div field of the structure and assign "2" as the default
value to the existing SoC's port config.
Device tree definitions of exynosautov9-spi will be added in separated
patchset to include usi(i2c/uart/spi) nodes all together.
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Intel Meteor Lake-P has the same SPI serial flash controller as Alder
Lake-P. Add Meteor Lake-P PCI ID to the driver list of supported
devices.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20220629113403.79942-1-mika.westerberg@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add exynosautov9 spi port configuration. It supports up to 12 spis so
MAX_SPI_PORTS should be increased from 6 to 12.
It has DIV_4 as the default internal clock divider and an internal
loopback mode to run a loopback test.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629102304.65712-5-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Modern exynos SoCs such as Exynos Auto v9 have different internal clock
divider, for example "4". To support this internal value, this adds
clk_div of the s3c64xx_spi_port_config and assign "2" as the default
value to existing s3c64xx_spi_port_config.
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220629102304.65712-3-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Modern exynos SoCs can support self loopback mode via setting BIT(3) of
MODE_CFG register. Previous SoCs don't have the bit so we need to add
has_loopback field in the s3c64xx_spi_port_config. Exynos Auto v9 SoC
has the bit and it will define the field to "true".
When it is set, SPI_LOOP mode will be marked.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629102304.65712-2-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Merge series from David Jander <david@protonic.nl>:
These patches optimize the spi_sync call for the common case that the
worker thread is idle and the queue is empty. It also opens the
possibility to potentially further optimize the async path also, since
it doesn't need to take into account the direct sync path anymore.
As an example for the performance gain, on an i.MX8MM SoC with a SPI CAN
controller attached (MCP2518FD), the time the interrupt line stays
active (which corresponds roughly with the time it takes to send 3
relatively short consecutive spi_sync messages) is reduced from 98us to
only 72us by this patch.
A note about message ordering:
This patch series should not change the behavior of message ordering when
coming from the same context. This means that if a client driver issues
one or more spi_async() messages immediately followed by a spi_sync()
message in the same context, it can still rely on these messages being
sent out in the order they were fired.
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This fixes the sequence of dma_release_channel.
Since commit f52b03c70744 ("spi: s3c64xx: requests spi-dma channel only
during data transfer"),
dma_release_channel has been located in the s3c64xx_spi_transfer_one
but this makes invalid return of can_dma callback.
__spi_unmap_msg will check whether the request is requested by dma or
not via can_dma callback. When it is calling to check it, the channels
will be already released at the end of s3c64xx_spi_transfer_one so the
callback function will return always "false". So, they can't be unmapped
from __spi_unmap_msg call. To fix this, we need to add
unprepare_transfer_hardware callback and move the dma_release_channel
from s3c64xx_spi_transfer_one to there.
Fixes: f52b03c70744 ("spi: s3c64xx: requests spi-dma channel only during data transfer")
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220627013845.138350-1-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add missing clk_disable_unprepare() in synquacer_spi_resume().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>
Link: https://lore.kernel.org/r/20220624005614.49434-1-guomengqi3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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There are only a few drivers that do not call
spi_finalize_current_message() in the context of transfer_one_message(),
and even for those cases the completion ctlr->cur_msg_completion is not
needed always. The calls to complete() and wait_for_completion() each
take a spin-lock, which is costly. This patch makes it possible to avoid
those calls in the big majority of cases, by introducing two flags that
with the help of ordering via barriers can avoid using the completion
safely. In case of a race with the context calling
spi_finalize_current_message(), the scheme errs on the safe side and takes
the completion.
The impact of this patch is worth the effort: On a i.MX8MM SoC, the time
the SPI bus is idle between two consecutive calls to spi_sync(), is
reduced from 19.6us to 16.8us... roughly 15%.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-12-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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This patch introduces a completion that is completed in
spi_finalize_current_message() and waited for in
__spi_pump_transfer_message(). This way all manipulation of ctlr->cur_msg
is done with the io_mutex held and strictly ordered:
__spi_pump_transfer_message() will not return until
spi_finalize_current_message() is done using ctlr->cur_msg, and its
calling context is only touching ctlr->cur_msg after returning.
Due to this, we can safely drop the spin-locks around ctlr->cur_msg.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-11-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Some drivers rely on this to point to the currently processed message, so
set this here also.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-10-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Now this flag is written entirely in the mutex, so no need for READ_ONCE
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-9-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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The ctlr->idling flag is never checked now, so we don't need to set it
either.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-8-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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Since the whole idling transition is locked by the io_mutex now, there is
no need to check this flag anymore.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-7-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
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