Various DMA users call the dmaengine_slave_config() and expect it to
succeed, but that can only succeed if .device_config is implemented.
Add empty device_config function rather than patching all the places
which use dmaengine_slave_config().
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20210804195140.61396-1-marex@denx.deSigned-off-by: Vinod Koul <vkoul@kernel.org>

Since we converted internal data types to match DT, there is no need to have
an intermediate conversion layer, hence drop a few conditionals and for loops
for good.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20210802184355.49879-3-andriy.shevchenko@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

u32 is a type that is used for properties retrieval from DT.
With the type change it allows to clean up properties reading routine.

While at it, order the fields in way how they are parsed.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20210802184355.49879-2-andriy.shevchenko@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Users are a bit frightened of the harmless message that tells that
DT is missed on ACPI-based platforms. Remove it for good, it will
simplify the future conversion to fwnode and device property APIs.

Fixes: a9ddb575 ("dmaengine: dw_dmac: Enhance device tree support")
Depends-on: f5e84eae ("dmaengine: dw: platform: Split OF helpers to separate module")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199379Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20210802184355.49879-1-andriy.shevchenko@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

status is no longer used within this block:

drivers/dma/idxd/irq.c:255:6: warning: unused variable 'status'
[-Wunused-variable]
                u8 status = desc->completion->status & DSA_COMP_STATUS_MASK;
                   ^
1 warning generated.

Fixes: b60bb6e2 ("dmaengine: idxd: fix abort status check")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20210802175820.3153920-1-nathan@kernel.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv')
so it must not be NULL.
Simplify the error handling logic about NULL 'alt_drv' in order to be
more robust and future-proof.

Fixes: 568b2126 ("dmaengine: idxd: fix uninit var for alt_drv")
Fixes: 6e7f3ee9 ("dmaengine: idxd: move dsa_drv support to compatible mode")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/77f0dc4f3966591d1f0cffb614a94085f8895a85.1627560174.git.christophe.jaillet@wanadoo.frSigned-off-by: Vinod Koul <vkoul@kernel.org>

Commit dea7a9fb ("dmaengine: imx-dma: remove dma_slave_config
direction usage") changes the method from a "configuration when called"
to an "configuration when used". Due to this, only the cyclic DMA type
gets configured correctly, while the generic DMA type is left
non-configured.

Without this additional call, the struct imxdma_channel::word_size member
is stuck at DMA_SLAVE_BUSWIDTH_UNDEFINED and imxdma_prep_slave_sg() always
returns NULL.
Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
Fixes: dea7a9fb ("dmaengine: imx-dma: remove dma_slave_config direction usage")
Link: https://lore.kernel.org/r/20210729071821.9857-1-jbe@pengutronix.deSigned-off-by: Vinod Koul <vkoul@kernel.org>

Commit dea7a9fb
  dmaengine: imx-dma: remove dma_slave_config direction usage

changes the method from a "configuration when called" to an "configuration
when used". Due to this, only the cyclic DMA type gets configured
correctly, while the generic DMA type is left non-configured.

Without this additional call, the struct imxdma_channel::word_size member
is stuck at DMA_SLAVE_BUSWIDTH_UNDEFINED and imxdma_prep_slave_sg() always
returns NULL.
Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
Link: https://lore.kernel.org/r/20210729071821.9857-1-jbe@pengutronix.deSigned-off-by: Vinod Koul <vkoul@kernel.org>

Use clk_prepare_enable()/clk_disable_unprepare() in preparation for switch
to Common Clock Framework, otherwise the following is visible:

WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:1011 clk_core_enable+0x9c/0xbc
Enabling unprepared m2p0
...
Hardware name: Cirrus Logic EDB9302 Evaluation Board
...
clk_core_enable
clk_core_enable_lock
ep93xx_dma_alloc_chan_resources
dma_chan_get
find_candidate
__dma_request_channel
snd_dmaengine_pcm_request_channel
dmaengine_pcm_new
snd_soc_pcm_component_new
soc_new_pcm
snd_soc_bind_card
edb93xx_probe
...
ep93xx-i2s ep93xx-i2s: Missing dma channel for stream: 0
ep93xx-i2s ep93xx-i2s: ASoC: error at snd_soc_pcm_component_new on ep93xx-i2s: -22
edb93xx-audio edb93xx-audio: ASoC: can't create pcm CS4271 HiFi :-22
edb93xx-audio edb93xx-audio: snd_soc_register_card() failed: -22
edb93xx-audio: probe of edb93xx-audio failed with error -22
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210726140001.24820-6-nikita.shubin@maquefel.meSigned-off-by: Vinod Koul <vkoul@kernel.org>

Burst length, DMA HW capability set in dt-binding is now used in driver.
Signed-off-by: Pandith N <pandith.n@intel.com>
Tested-by: Pan Kris <kris.pan@intel.com>
Link: https://lore.kernel.org/r/20210802055454.15192-4-pandith.n@intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Added support for multiple DMA_MEM_TO_DEV, DMA_DEV_TO_MEM transfers in
parallel. This is required for peripherals using DMA for transmit and
receive operations at the same time. APB slot number needs to be
programmed in channel hardware handshaking interface
Signed-off-by: Pandith N <pandith.n@intel.com>
Tested-by: Pan Kris <kris.pan@intel.com>
Link: https://lore.kernel.org/r/20210802055454.15192-3-pandith.n@intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Removed free slot check algorithm in dw_axi_dma_set_hw_channel. For 8
DMA channels, use respective handshake slot in DMA_HS_SEL APB register.

For every channel, an dedicated slot is provided in  hardware handshake
register AXIDMA_CTRL_DMA_HS_SEL_n. Peripheral source number is
programmed in respective channel slots.
Signed-off-by: Pandith N <pandith.n@intel.com>
Tested-by: Pan Kris <kris.pan@intel.com>
Link: https://lore.kernel.org/r/20210802055454.15192-2-pandith.n@intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The usb_dmac_get_current_residue function used to
take a signed integer as a pos parameter.
The only callers of this function passes an unsigned integer to it.
Therefore to make it obviously safe, let's just make this an unsgined
integer as this is used in pointer arithmetics.
Signed-off-by: Jordy Zomer <jordy@pwning.systems>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210731091939.510816-1-jordy@pwning.systemsSigned-off-by: Vinod Koul <vkoul@kernel.org>

Coverity static analysis of linux-next found issue.

The check (status == IDXD_COMP_DESC_ABORT) is always false since status
was previously masked with 0x7f and IDXD_COMP_DESC_ABORT is 0xff.

Fixes: 6b4b87f2 ("dmaengine: idxd: fix submission race window")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162698465160.3560828.18173186265683415384.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Enabling device and wq returns standard errno and that does not provide
enough details to indicate what exactly failed. The hardware command status
is only 8bits. Expand the command status to 32bits and use the upper 16
bits to define software errors to provide more details on the exact
failure. Bit 31 will be used to indicate the error is software set as the
driver is using some of the spec defined hardware error as well.

Cc: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162681373579.1968485.5891788397526827892.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The device submission portal is on a 4k page and any of those 64bit aligned
address on the page can be used for descriptor submission. By rotating the
offset through the 4k range and prevent successive writes to the same MMIO
address, performance improvement is observed through testing.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162681372446.1968485.10634280461681015569.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The sbitmap wait and allocate routine checks the index that is returned
from sbitmap_queue_get(). It should be idxd >= 0 as 0 is also a valid
index. This fixes issue where submission path hangs when WQ size is 1.

Fixes: 0705107f ("dmaengine: idxd: move submission to sbitmap_queue")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162697645067.3478714.506720687816951762.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

0-day detected uninitialized alt_drv variable in the bind_store() function.
The branch can be taken when device is not idxd device or wq 'struct
device'. Init alt_drv to NULL.

Fixes: 6e7f3ee9 ("dmaengine: idxd: move dsa_drv support to compatible mode")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162689250332.2114335.636367120454420852.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Set GRPCFG traffic class to value of 1 for best performance on current
generation of accelerators. Also add override option to allow experimentation.
Sysfs knobs are disabled for DSA/IAX gen1 devices.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162681373005.1968485.3761065664382799202.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

When using SCMI clocks, the clocks are probed later than subsys initcall
level. This driver uses platform_driver_probe which is not compatible with
deferred probing and won't be probed again later if probe function fails
due to clocks not being available at that time.

This patch replaces the use of platform_driver_probe with
platform_driver_register which will allow probing the driver later again
when clocks will be available.
Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Link: https://lore.kernel.org/r/20210728094607.50589-1-clement.leger@bootlin.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

If the router_xlate can not find the controller in the available DMA
devices then it should return with -EPORBE_DEFER in a same way as the
of_dma_request_slave_channel() does.

The issue can be reproduced if the event router is registered before the
DMA controller itself and a driver would request for a channel before the
controller is registered.
In of_dma_request_slave_channel():
1. of_dma_find_controller() would find the dma_router
2. ofdma->of_dma_xlate() would fail and returned NULL
3. -ENODEV is returned as error code

with this patch we would return in this case the correct -EPROBE_DEFER and
the client can try to request the channel later.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20210717190021.21897-1-peter.ujfalusi@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

use pm_runtime_resume_and_get() to replace pm_runtime_get_sync and
pm_runtime_put_noidle. this change is just to simplify the code,
there is no actual functional change.
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20210607064640.121394-4-zhangqilong3@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Fix the checkpatch.pl warning: "Prefer kstrto<type> to single variable sscanf".
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Link: https://lore.kernel.org/r/20210710165432.GA690401@pcSigned-off-by: Vinod Koul <vkoul@kernel.org>

STM32 USART/UART is not managing correctly the default DMA REQ/ACK protocol
leading to possibly lock the DMA stream.
Default protocol consists in maintaining ACK signal up to the removal of
REQuest and the transfer completion.
In case of alternative REQ/ACK protocol, ACK de-assertion does not wait the
removal of the REQuest, but only the transfer completion.

This patch retrieves the need of the alternative protocol through the
device tree, and sets the protocol accordingly.
It also unwrap STM32_DMA_DIRECT_MODE_GET macro definition for consistency
with new STM32_DMA_ALT_ACK_MODE_GET macro definition.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20210624093959.142265-3-amelie.delaunay@foss.st.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Default REQ/ACK protocol consists in maintaining ACK signal up to the
removal of REQuest and the transfer completion.
In case of alternative REQ/ACK protocol, ACK de-assertion does not wait the
removal of the REQuest, but only the transfer completion.
Due to a possible DMA stream lock when transferring data to/from STM32
USART/UART, this new bindings allow to select this alternative protocol in
device tree, especially for STM32 USART/UART nodes.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210624093959.142265-2-amelie.delaunay@foss.st.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The response slave port can be disabled in some configuration [1] and
csr + MSGDMA_CSR_RESP_FILL_LEVEL will be 0 even if transfer has suceeded.
We have to only rely on the interrupts in that scenario.
This was tested on cyclone V with the controller resp port disabled.

[1] https://www.intel.com/content/www/us/en/programmable/documentation/sfo1400787952932.html
30.3.1.2
30.3.1.3
30.5.5

Fixes: https://forum.rocketboards.org/t/ip-msgdma-linux-driver/1919Signed-off-by: Olivier Dautricourt <olivier.dautricourt@orolia.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/8220756f2191ca08cb21702252d1f2d4f753a7f5.1623898678.git.olivier.dautricourt@orolia.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Response port is not required in some configuration of the IP core.
Signed-off-by: Olivier Dautricourt <olivier.dautricourt@orolia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/fb28146a23a182be9e5435c1d3e5cac36b372294.1623898678.git.olivier.dautricourt@orolia.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

When using 'pcim_enable_device()', 'pci_alloc_irq_vectors()' is
auto-magically a managed function.

It is useless (but harmless) to record an action to explicitly call
'pci_free_irq_vectors()'.

So keep things simple, comment why and how these resources are freed, axe
some useless code and save some memory.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/4f8932e2d0d8d092bf60272511100030e013bc72.1623875508.git.christophe.jaillet@wanadoo.frSigned-off-by: Vinod Koul <vkoul@kernel.org>

Using list_move_tail() instead of list_del() + list_add_tail().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20210609071349.1336853-1-libaokun1@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Using list_move_tail() instead of list_del() + list_add_tail().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20210609072802.1368785-1-libaokun1@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Using list_move_tail() instead of list_del() + list_add_tail().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/20210608030905.2818831-1-libaokun1@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

pm_runtime_get_sync will increment pm usage counter
even it failed. Forgetting to putting operation will
result in reference leak here. We fix it by replacing
it with pm_runtime_resume_and_get to keep usage counter
balanced.

Fixes: 4f3ceca2 ("dmaengine: stm32-dmamux: Add PM Runtime support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20210607064640.121394-3-zhangqilong3@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

pm_runtime_get_sync will increment pm usage counter
even it failed. Forgetting to putting operation will
result in reference leak here. We fix it by replacing
it with pm_runtime_resume_and_get to keep usage counter
balanced.

Fixes: 48bc73ba ("dmaengine: stm32-dma: Add PM Runtime support")
Fixes: 05f8740a ("dmaengine: stm32-dma: add suspend/resume power management support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20210607064640.121394-2-zhangqilong3@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

This helps to remove conflict on idxd driver

 Conflicts:
	drivers/dma/idxd/sysfs.c
	drivers/dma/idxd/bus.c

Greg says:

Bus: Make remove callback return void tag

Tag for other trees/branches to pull from in order to have a stable
place to build off of if they want to add new busses for 5.15.
Signed-off-by: Vinod Koul <vkoul@kernel.org>

The function uniphier_xdmac_chan_stop() is only called in atomic state.
Should use readl_poll_timeout_atomic() there instead of
readl_poll_timeout().
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 667b9251 ("dmaengine: uniphier-xdmac: Add UniPhier external DMA controller driver")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1627364852-28432-1-git-send-email-hayashi.kunihiko@socionext.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver core ignores the return value of scmdev_remove()
(because there is only little it can do when a device disappears).

So make it impossible for future drivers to return an unused error code
by changing the remove prototype to return void.

The real motivation for this change is the quest to make struct
bus_type::remove return void, too.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-5-u.kleine-koenig@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver core only calls a bus remove callback when there is a driver.
So dev->driver is never NULL and the check can safely be removed.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-4-u.kleine-koenig@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver core ignores the return value of css_remove()
(because there is only little it can do when a device disappears) and
all callbacks return 0 anyhow.

So make it impossible for future drivers to return an unused error code
by changing the remove prototype to return void.

The real motivation for this change is the quest to make struct
bus_type::remove return void, too.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-3-u.kleine-koenig@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>