Commit 53326135d0 ("i2c: riic: Add suspend/resume support") added
suspend support for the Renesas I2C driver and following this change
on RZ/G3E the following WARNING is seen on entering suspend ...
[ 134.275704] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[ 134.285536] ------------[ cut here ]------------
[ 134.290298] i2c i2c-2: Transfer while suspended
[ 134.295174] WARNING: drivers/i2c/i2c-core.h:56 at __i2c_smbus_xfer+0x1e4/0x214, CPU#0: systemd-sleep/388
[ 134.365507] Tainted: [W]=WARN
[ 134.368485] Hardware name: Renesas SMARC EVK version 2 based on r9a09g047e57 (DT)
[ 134.375961] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 134.382935] pc : __i2c_smbus_xfer+0x1e4/0x214
[ 134.387329] lr : __i2c_smbus_xfer+0x1e4/0x214
[ 134.391717] sp : ffff800083f23860
[ 134.395040] x29: ffff800083f23860 x28: 0000000000000000 x27: ffff800082ed5d60
[ 134.402226] x26: 0000001f4395fd74 x25: 0000000000000007 x24: 0000000000000001
[ 134.409408] x23: 0000000000000000 x22: 000000000000006f x21: ffff800083f23936
[ 134.416589] x20: ffff0000c090e140 x19: ffff0000c090e0d0 x18: 0000000000000006
[ 134.423771] x17: 6f63657320313030 x16: 2e30206465737061 x15: ffff800083f23280
[ 134.430953] x14: 0000000000000000 x13: ffff800082b16ce8 x12: 0000000000000f09
[ 134.438134] x11: 0000000000000503 x10: ffff800082b6ece8 x9 : ffff800082b16ce8
[ 134.445315] x8 : 00000000ffffefff x7 : ffff800082b6ece8 x6 : 80000000fffff000
[ 134.452495] x5 : 0000000000000504 x4 : 0000000000000000 x3 : 0000000000000000
[ 134.459672] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c9ee9e80
[ 134.466851] Call trace:
[ 134.469311] __i2c_smbus_xfer+0x1e4/0x214 (P)
[ 134.473715] i2c_smbus_xfer+0xbc/0x120
[ 134.477507] i2c_smbus_read_byte_data+0x4c/0x84
[ 134.482077] isl1208_i2c_read_time+0x44/0x178 [rtc_isl1208]
[ 134.487703] isl1208_rtc_read_time+0x14/0x20 [rtc_isl1208]
[ 134.493226] __rtc_read_time+0x44/0x88
[ 134.497012] rtc_read_time+0x3c/0x68
[ 134.500622] rtc_suspend+0x9c/0x170
The warning is triggered because I2C transfers can still be attempted
while the controller is already suspended, due to inappropriate ordering
of the system sleep callbacks.
If the controller is autosuspended, there is no way to wake it up once
runtime PM disabled (in suspend_late()). During system resume, the I2C
controller will be available only after runtime PM is re-enabled
(in resume_early()). However, this may be too late for some devices.
Wake up the controller in the suspend() callback while runtime PM is
still enabled. The I2C controller will remain available until the
suspend_noirq() callback (pm_runtime_force_suspend()) is called. During
resume, the I2C controller can be restored by the resume_noirq() callback
(pm_runtime_force_resume()). Finally, the resume() callback re-enables
autosuspend. As a result, the I2C controller can remain available until
the system enters suspend_noirq() and from resume_noirq().
Cc: stable@vger.kernel.org
Fixes: 53326135d0 ("i2c: riic: Add suspend/resume support")
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Tested-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Apart from runtime PM, there is nothing in common between i2c_dw_xfer()
and amd_i2c_dw_xfer_quirk(), so give AMD NAVI controller its own algorithm
instead of calling the quirk from i2c_dw_xfer().
Add runtime PM handling to amd_i2c_dw_xfer_quirk() and a dedicated
i2c_algorithm for AMD NAVI controllers. The adapter algorithm is set
during probe based on the device model.
This way we avoid checking for the device model at the start of every
transfer.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Benoît Monin <benoit.monin@bootlin.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251126-i2c-dw-v4-4-b0654598e7c5@bootlin.com
'i2c_types' is an enum, thus cast of pointer on 64-bit compile test with
clang and W=1 causes:
i2c-rcar.c:1144:18: error: cast to smaller integer type 'enum rcar_i2c_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
One of the discussions in 2023 on LKML suggested warning is not suitable
for kernel. Nothing changed in this regard since that time, so assume
the warning will stay and we want to have warnings-free builds.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251126182257.157439-6-krzysztof.kozlowski@oss.qualcomm.com
'i2c_types' is an enum, thus cast of pointer on 64-bit compile test with
clang and W=1 causes:
i2c-pxa.c:1269:15: error: cast to smaller integer type 'enum pxa_i2c_types' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
One of the discussions in 2023 on LKML suggested warning is not suitable
for kernel. Nothing changed in this regard since that time, so assume
the warning will stay and we want to have warnings-free builds.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251126182257.157439-5-krzysztof.kozlowski@oss.qualcomm.com
'type' is an enum, thus cast of pointer on 64-bit compile test with
clang and W=1 causes:
i2c-bcm-iproc.c:1102:3: error: cast to smaller integer type 'enum bcm_iproc_i2c_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
One of the discussions in 2023 on LKML suggested warning is not suitable
for kernel. Nothing changed in this regard since that time, so assume
the warning will stay and we want to have warnings-free builds.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251126182257.157439-4-krzysztof.kozlowski@oss.qualcomm.com
Pull i2c updates from Wolfram Sang:
- general cleanups in bcm2835, designware, pcf8584, and stm32
- amd-mp2: fix device refcount
- designware: avoid interrupt storms caused by bad firmware
- spacemit: fix device detection failures
- new devices: Intel Diamond Rapids, Rockchip RK3506, Qualcomm
Kaanapali and MSM8953
- minor fixes to i801, core documentation, elektor Kconfig dependencies
- at24 updates: add new compatible for Belling BL24S64
* tag 'i2c-for-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (21 commits)
i2c: qcom-cci: Add msm8953 compatible
i2c: spacemit: fix detect issue
i2c: amd-mp2: fix reference leak in MP2 PCI device
i2c: i2c.h: fix a bad kernel-doc line
i2c: i2c-elektor: Allow building on SMP kernels
dt-bindings: i2c: qcom-cci: Document Kaanapali compatible
dt-bindings: i2c: qcom-cci: Document msm8953 compatible
dt-bindings: eeprom: at24: Add compatible for Belling BL24S64
i2c: i801: Fix the Intel Diamond Rapids features
i2c: pcf8584: Change pcf_doAdress() to pcf_send_address()
i2c: pcf8584: Make pcf_doAddress() function void
i2c: pcf8584: Move 'ret' variable inside for loop, goto out if ret < 0.
i2c: designware: Disable SMBus interrupts to prevent storms from mis-configured firmware
dt-bindings: i2c: i2c-rk3x: Add compatible string for RK3506
i2c: i801: Add support for Intel Diamond Rapids
i2c: stm32: Omit two variable reassignments in stm32_i2c_dma_request()
i2c: designware: Omit a variable reassignment in dw_i2c_plat_probe()
i2c: pcf8584: Fix do not use assignment inside if conditional
i2c: pcf8584: Remove debug macros from i2c-algo-pcf.c
i2c: busses: bcm2835: convert from round_rate() to determine_rate()
...
Pull dmaengine updates from Vinod Koul:
- Renesas driver conversion to RUNTIME_PM_OPS() etc
- Dropping module alias on bunch of drivers
- GPI Block event interrupt support in Qualcomm driver and updates to
I2C driver as well
* tag 'dmaengine-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (23 commits)
dt-bindings: dma: xilinx: Simplify dma-coherent property
dmaengine: fsl-edma: configure tcd attr with separate src and dst settings
dmaengine: st_fdma: drop unused module alias
dmaengine: bcm2835: enable compile testing
dmaengine: tegra210-adma: drop unused module alias
dmaengine: sprd: drop unused module alias
dmaengine: mmp_tdma: drop unnecessary OF node check in remove
dmaengine: mmp_tdma: drop unused module alias
dmaengine: k3dma: drop unused module alias
dmaengine: fsl-qdma: drop unused module alias
dmaengine: fsl-edma: drop unused module alias
dmaengine: dw: drop unused module alias
dmaengine: bcm2835: drop unused module alias
dmaengine: at_hdmac: add COMPILE_TEST support
dmaengine: at_hdmac: fix formats under 64-bit
i2c: i2c-qcom-geni: Add Block event interrupt support
dmaengine: qcom: gpi: Add GPI Block event interrupt support
dmaengine: idxd: drain ATS translations when disabling WQ
dmaengine: sh: Kconfig: Drop ARCH_R7S72100/ARCH_RZG2L dependency
dmaengine: rcar-dmac: Convert to NOIRQ_SYSTEM_SLEEP/RUNTIME_PM_OPS()
...
This commit addresses two issues causing i2c detect to fail.
The identified issues are:
1. Incorrect error handling for BED (Bus Error No ACK/NAK):
Before this commit, Both ALD (Arbitration Loss Detected) and
BED returned -EAGAIN.
2. Missing interrupt status clear after initialization in xfer():
On the K1 SoC, simply fixing the first issue changed the error
from -EAGAIN to -ETIMEOUT. Through tracing, it was determined that
this is likely due to MSD (Master Stop Detected) latency issues.
That means the MSD bit in the ISR may still be set on the next transfer.
As a result, the controller won't work — we can see from the scope that
it doesn't issue any signal.
(This only occurs during rapid consecutive I2C transfers.
That explains why the issue only shows up with i2cdetect.)
With these two fixes, i2c device detection now functions correctly on the K1 SoC.
Fixes: 5ea558473f ("i2c: spacemit: add support for SpacemiT K1 SoC")
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Tested-by: Michael Opdenacker <michael.opdenacker@rootcommit.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251113-fix-k1-detect-failure-v2-1-b02a9a74f65a@linux.spacemit.com
In i2c_amd_probe(), amd_mp2_find_device() utilizes
driver_find_next_device() which internally calls driver_find_device()
to locate the matching device. driver_find_device() increments the
reference count of the found device by calling get_device(), but
amd_mp2_find_device() fails to call put_device() to decrement the
reference count before returning. This results in a reference count
leak of the PCI device each time i2c_amd_probe() is executed, which
may prevent the device from being properly released and cause a memory
leak.
Found by code review.
Cc: stable@vger.kernel.org
Fixes: 529766e0a0 ("i2c: Add drivers for the AMD PCIe MP2 I2C controller")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251022095402.8846-1-make24@iscas.ac.cn
In the past, the i2c-elektor driver was broken on SMP. Since then, there
appear to have been some fixes and cleanup work (as pointed out by Wolfram
Sang) to get rid of cli/sti usage and rely on spinlocks instead. Therefore,
let's allow building the driver on SMP kernels again.
I've tested this driver on an SMP kernel on an Alpha UP2000+ for a few days
without any problems.
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Revert commit 690de2902d ("i2c: muxes: pca954x: Use reset controller
only") and its dependent commit 94c2967764 ("i2c: muxes: pca954x:
Reset if (de)select fails") because the first breaks all users of the
driver, by requiring a completely optional reset-gpio driver. These
commits cause that mux driver simply stops working when optional
reset-gpio is not included, but that reset-gpio is not pulled anyhow.
Driver cannot remove legacy reset-gpios handling.
Fixes: 690de2902d ("i2c: muxes: pca954x: Use reset controller only")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
An error code was assigned to a variable and checked accordingly.
This value was passed to a dev_err_probe() call in an if branch.
This function is documented in the way that the same value is returned.
Thus delete two redundant variable reassignments.
The source code was transformed by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/f7e0c023-d2d1-40ba-badb-74a7e9c23684@web.de
When building certain configurations with CONFIG_FINEIBT=y after
commit 894af4a1cd ("objtool: Validate kCFI calls"), there is a
warning due to an indirect call in dw_i2c_plat_remove():
$ cat allno.config
CONFIG_ACPI=y
CONFIG_CFI=y
CONFIG_COMMON_CLK=y
CONFIG_CPU_MITIGATIONS=y
CONFIG_I2C=y
CONFIG_I2C_DESIGNWARE_BAYTRAIL=y
CONFIG_I2C_DESIGNWARE_CORE=y
CONFIG_I2C_DESIGNWARE_PLATFORM=y
CONFIG_IOSF_MBI=y
CONFIG_MITIGATION_RETPOLINE=y
CONFIG_MODULES=y
CONFIG_PCI=y
CONFIG_X86_KERNEL_IBT=y
$ make -skj"$(nproc)" ARCH=x86_64 LLVM=1 clean allnoconfig vmlinux
vmlinux.o: warning: objtool: dw_i2c_plat_remove+0x3c: no-cfi indirect call!
With this configuration, i2c_dw_semaphore_cb_table has the BAYTRAIL
member and the sentinel (i.e., 2 members), both of which have an
implicit
.remove = NULL,
so Clang effectively turns i2c_dw_remove_lock_support(), which is later
inlined into dw_i2c_plat_remove(), into:
static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
{
if (dev->semaphore_idx > 2)
(*NULL)(dev):
}
which is not necessarily problematic from a logic perspective (as the
code was not bounds checking semaphore_idx so an out of bounds index
could already crash) but objtool's new __nocfi indirect call checking
trips over Clang dropping the kCFI setup from a known NULL indirect
call.
While it would be possible to fix this by transforming the initial check
into
if (dev->semaphore_idx < 0 || dev->semaphore_idx >= ARRAY_SIZE(i2c_dw_semaphore_cb_table))
the remove member is unused after commit 440da737cf ("i2c: designware:
Use PCI PSP driver for communication"), so i2c_dw_remove_lock_support()
can be removed altogether, as it will never actually do anything.
Closes: https://github.com/ClangBuiltLinux/linux/issues/2133
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20251013-dw_i2c_plat_remove-avoid-objtool-no-cfi-warning-v1-1-8cc4842967bf@kernel.org
The I2C driver gets an interrupt upon transfer completion.
When handling multiple messages in a single transfer, this
results in N interrupts for N messages, leading to significant
software interrupt latency.
To mitigate this latency, utilize Block Event Interrupt (BEI)
mechanism. Enabling BEI instructs the hardware to prevent interrupt
generation and BEI is disabled when an interrupt is necessary.
Large I2C transfer can be divided into chunks of messages internally.
Interrupts are not expected for the messages for which BEI bit set,
only the last message triggers an interrupt, indicating the completion of
N messages. This BEI mechanism enhances overall transfer efficiency.
BEI optimizations are currently implemented for I2C write transfers only,
as there is no use case for multiple I2C read messages in a single transfer
at this time.
Signed-off-by: Jyothi Kumar Seerapu <quic_jseerapu@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Mukesh Savaliya <mukesh.savaliya@oss.qualcomm.com>
Acked-by: Mukesh Savaliya <mukesh.savaliya@oss.qualcomm.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
pm_runtime_put_autosuspend(), pm_runtime_put_sync_autosuspend(),
pm_runtime_autosuspend() and pm_request_autosuspend() now include a call
to pm_runtime_mark_last_busy(). Remove the now-reduntant explicit call to
pm_runtime_mark_last_busy().
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Pull more i2c updates from Wolfram Sang:
- Second part of rtl9300 updates since dependencies are in now:
- general cleanups
- implement block read/write support
- add RTL9310 support
- DT schema conversion of hix5hd2 binding
- namespace cleanup for i2c-algo-pca
- minor simplification for mt65xx
* tag 'i2c-for-6.18-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
dt-bindings: i2c: hisilicon,hix5hd2: convert to DT schema
i2c: mt65xx: convert set_speed function to void
i2c: rename wait_for_completion callback to wait_for_completion_cb
i2c: rtl9300: add support for RTL9310 I2C controller
dt-bindings: i2c: realtek,rtl9301-i2c: extend for RTL9310 support
i2c: rtl9300: use scoped guard instead of explicit lock/unlock
i2c: rtl9300: separate xfer configuration and execution
i2c: rtl9300: do not set read mode on every transfer
i2c: rtl9300: move setting SCL frequency to config_io
i2c: rtl9300: rename internal sda_pin to sda_num
dt-bindings: i2c: realtek,rtl9301-i2c: fix wording and typos
i2c: rtl9300: use regmap fields and API for registers
i2c: rtl9300: Implement I2C block read and write
Pull USB / Thunderbolt updates from Greg KH:
"Here is the big set of USB and thunderbolt drivers for 6.18-rc1. It
was another normal development cycle, with lots of the usual drivers
getting updates:
- Thunderbolt driver cleanups and additions
- dwc3 driver updates
- dwc2 driver updates
- typec driver updates
- xhci driver updates and additions
- offload USB engine updates for better power management
- unused tracepoint removals
- usb gadget fixes and updates as more users start to rely on these
drivers instead of the "old" function gadget drivers
- new USB device ids
- other minor driver USB driver updates
- new USB I/O driver framework and driver additions"
The last item, the usb i/o driver, has an i2c and gpio driver added
through this tree. Those drivers were acked by the respective
subsystem maintainers.
All of these have been in linux-next for a while"
* tag 'usb-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (132 commits)
usb: vhci-hcd: Prevent suspending virtually attached devices
USB: serial: option: add SIMCom 8230C compositions
thunderbolt: Fix use-after-free in tb_dp_dprx_work
usb: xhci: align PORTSC trace with one-based port numbering
usb: xhci: correct indentation for PORTSC tracing function
usb: xhci: improve TR Dequeue Pointer mask
usb: xhci-pci: add support for hosts with zero USB3 ports
usb: xhci: Update a comment about Stop Endpoint retries
Revert "usb: xhci: Avoid Stop Endpoint retry loop if the endpoint seems Running"
usb: gadget: f_rndis: Refactor bind path to use __free()
usb: gadget: f_ecm: Refactor bind path to use __free()
usb: gadget: f_acm: Refactor bind path to use __free()
usb: gadget: f_ncm: Refactor bind path to use __free()
usb: gadget: Introduce free_usb_request helper
usb: gadget: Store endpoint pointer in usb_request
usb: host: xhci-rcar: Add Renesas RZ/G3E USB3 Host driver support
usb: host: xhci-plat: Add .post_resume_quirk for struct xhci_plat_priv
usb: host: xhci-rcar: Move R-Car reg definitions
dt-bindings: usb: Document Renesas RZ/G3E USB3HOST
usb: gadget: f_fs: Fix epfile null pointer access after ep enable.
...
cppcheck rightfully reports:
drivers/i2c/busses/i2c-mt65xx.c:1464:6: warning: Condition 'ret' is always false [knownConditionTrueFalse]
Make the function void and simplify the code.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Functionally no change. Remove the ambiguity of 'wait_for_completion'.
It helps development of the DEPT dependency tracker, but seems favorable
in any case.
Signed-off-by: Byungchul Park <byungchul@sk.com>
[wsa: reworded commit message]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Add support for the internal I2C controllers of RTL9310 series based
SoCs to the driver for RTL9300. Add register definitions, chip-specific
functions and compatible strings for known RTL9310-based SoCs RTL9311,
RTL9312 and RTL9313.
Make use of a new device tree property 'realtek,scl' which needs to be
specified in case both or only the second master is used. This is
required due how the register layout changed in contrast to RTL9300,
which has SCL selection in a global register instead of a
master-specific one.
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Tested-by: Sven Eckelmann <sven@narfation.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250927101931.71575-10-jelonek.jonas@gmail.com
So far, the rtl9300_i2c_smbus_xfer code is quite a mess with function
calls distributed over the whole function setting different values in
different cases. Calls to rtl9300_i2c_config_xfer and
rtl9300_i2c_reg_addr_set are used in every case-block with varying
values whose meaning is not instantly obvious. In some cases, there are
additional calls within these case-blocks doing more things.
This is in general a bad design and especially really bad for
readability and maintainability because it distributes changes or
issues to multiple locations due to the same function being called with
different hardcoded values in different places.
To have a good structure, setting different parameters based on the
desired operation should not be interleaved with applying these
parameters to the hardware registers. Or in different words, the
parameter site should be mixed with the call site.
Thus, separate configuration and execution of an SMBus xfer within
rtl9300_i2c_smbus_xfer to improve readability and maintainability. Add a
new 'struct rtl9300_i2c_xfer' to carry the required parameters for an
xfer which are configured based on the input parameters within a single
switch-case block, without having any function calls within this block.
The function calls to actually apply these values to the hardware
registers then appear below in a single place and just operate on the
passed instance of 'struct rtl9300_i2c_xfer'. These are
'rtl9300_i2c_prepare_xfer' which combines applying all parameters of the
xfer to the corresponding register, and 'rtl9300_i2c_do_xfer' which
actually executes the xfer and does post-processing if needed.
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Tested-by: Sven Eckelmann <sven@narfation.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> # On RTL9302C based board
Tested-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250927101931.71575-7-jelonek.jonas@gmail.com
