* Re: [PATCH v5 00/21] Virtual Swap Space
From: YoungJun Park @ 2026-04-14 3:09 UTC (permalink / raw)
To: Nhat Pham
Cc: Kairui Song, Liam.Howlett, akpm, apopple, axelrasmussen, baohua,
baolin.wang, bhe, byungchul, cgroups, chengming.zhou, chrisl,
corbet, david, dev.jain, gourry, hannes, hughd, jannh,
joshua.hahnjy, lance.yang, lenb, linux-doc, linux-kernel,
linux-mm, linux-pm, lorenzo.stoakes, matthew.brost, mhocko,
muchun.song, npache, pavel, peterx, peterz, pfalcato, rafael,
rakie.kim, roman.gushchin, rppt, ryan.roberts, shakeel.butt,
shikemeng, surenb, tglx, vbabka, weixugc, ying.huang, yosry.ahmed,
yuanchu, zhengqi.arch, ziy, kernel-team, riel
In-Reply-To: <CAKEwX=Pt04pYfhYOwmtXJKU5OqcxBC14SAf1wpBxBo1D7rPpGw@mail.gmail.com>
On Sat, Apr 11, 2026 at 06:03:04PM -0700, Nhat Pham wrote:
> On Wed, Mar 25, 2026 at 11:53 AM YoungJun Park <youngjun.park@lge.com> wrote:
> >
> > On Mon, Mar 23, 2026 at 11:32:57AM -0400, Nhat Pham wrote:
> >
> > > Interesting. Normally "lots of zero-filled page" is a very beneficial
> > > case for vswap. You don't need a swapfile, or any zram/zswap metadata
> > > overhead - it's a native swap backend. If production workload has this
> > > many zero-filled pages, I think the numbers of vswap would be much
> > > less alarming - perhaps even matching memory overhead because you
> > > don't need to maintain a zram entry metadata (it's at least 2 words
> > > per zram entry right?), while there's no reverse map overhead induced
> > > (so it's 24 bytes on both side), and no need to do zram-side locking
> > > :)
> > >
> > > So I was surprised to see that it's not working out very well here. I
> > > checked the implementation of memhog - let me know if this is wrong
> > > place to look:
> > >
> > > https://man7.org/linux/man-pages/man8/memhog.8.html
> > > https://github.com/numactl/numactl/blob/master/memhog.c#L52
> > >
> > > I think this is what happened here: memhog was populating the memory
> > > 0xff, which triggers the full overhead of a swapfile-backed swap entry
> > > because even though it's "same-filled" it's not zero-filled! I was
> > > following Usama's observation - "less than 1% of the same-filled pages
> > > were non-zero" - and so I only handled the zero-filled case here:
> > >
> > > https://lore.kernel.org/all/20240530102126.357438-1-usamaarif642@gmail.com/
> > >
> > > This sounds a bit artificial IMHO - as Usama pointed out above, I
> > > think most samefilled pages are zero pages, in real production
> > > workloads. However, if you think there are real use cases with a lot
> > > of non-zero samefilled pages, please let me know I can fix this real
> > > quick. We can support this in vswap with zero extra metadata overhead
> > > - change the VSWAP_ZERO swap entry type to VSWAP_SAME_FILLED, then use
> > > the backend field to store that value. I can send you a patch if
> > > you're interested.
> >
> > This brings back memories -- I'm pretty sure we talked about
> > exactly this at LPC. Our custom swap device already handles both
> > zero-filled and same-filled pages on its own, so what we really
> > wanted was a way to tell the swap layer "just skip the detection
> > and let it through."
> >
> > I looked at two approaches back then but never submitted either:
> >
> > - A per-swap_info flag to opt out of zero/same-filled handling.
> > But this felt wrong from vswap's perspective -- if even one
> > device opts out of the zeromap, the model gets messy.
> >
> > - Revisiting Usama's patch 2 approach.
> > Sounded good in theory, but as you said,
> > it's not as simple to verify in practice. And it is more clean design
> > swapout time zero check as I see. So, I gave up on it.
> >
> > Seeing this come up again is actually kind of nice :)
> >
> > One thought -- maybe a compile-time CONFIG or a boot param to
> > control the scope? e.g. zero-only, same-filled, or disabled.
> > That way vendors like us just turn it off, and setups like
> > Kairui's can opt into broader detection. Just an idea though --
> > open to other approaches if you have something in mind.
>
> Yeah for vswap it's probably going to be a CONFIG or boot param.
>
> But in the status quo, we can always add a swapfile flag. That one
> should work already, right?
I'm a bit hesitant about the swapfile flag approach. If vswap gets merged,
handling devices with this flag set might complicate the vswap design.
Moreover, exposing a new swap flag to the user interface (e.g., at swapon)
raises concerns about backward compatibility. Do you think that would be safe?
Since our use case isn't very common, we just need a simple knob to tune it.
That's why I still prefer a boot param or CONFIG approach.
Thanks :D
Youngjun Park
^ permalink raw reply
* Re: [PATCH v5 00/21] Virtual Swap Space
From: Kairui Song @ 2026-04-14 3:28 UTC (permalink / raw)
To: YoungJun Park
Cc: Nhat Pham, Liam.Howlett, akpm, apopple, axelrasmussen, baohua,
baolin.wang, bhe, byungchul, cgroups, chengming.zhou, chrisl,
corbet, david, dev.jain, gourry, hannes, hughd, jannh,
joshua.hahnjy, lance.yang, lenb, linux-doc, linux-kernel,
linux-mm, linux-pm, lorenzo.stoakes, matthew.brost, mhocko,
muchun.song, npache, pavel, peterx, peterz, pfalcato, rafael,
rakie.kim, roman.gushchin, rppt, ryan.roberts, shakeel.butt,
shikemeng, surenb, tglx, vbabka, weixugc, ying.huang, yosry.ahmed,
yuanchu, zhengqi.arch, ziy, kernel-team, riel
In-Reply-To: <ad2rYH9tUPthHFoj@yjaykim-PowerEdge-T330>
On Tue, Apr 14, 2026 at 11:05 AM YoungJun Park <youngjun.park@lge.com> wrote:
>
Hi All,
> On Sat, Apr 11, 2026 at 06:40:44PM -0700, Nhat Pham wrote:
> > > 1. Modularization
> > >
> > > You removed CONFIG_* and went with a unified approach. I recall
> > > you were also considering a module-based structure at some point.
> > > What are your thoughts on that direction?
> > >
> >
> > The CONFIG-based approach was a huge mess. It makes me not want to
> > look at the code, and I'm the author :)
> >
> > > If we take that approach, we could extend the recent swap ops
> > > patchset (https://lore.kernel.org/linux-mm/20260302104016.163542-1-bhe@redhat.com/)
> > > as follows:
> > > - Make vswap a swap module
> > > - Have cluster allocation functions reside in swapops
> > > - Enable vswap through swapon
> >
> > Hmmmmm.
>
> I think this would be a happy world, but I wonder what others think.
> Anyway, I'm looking forward to the future direction.
>
Yeah, I agree with this.
And I do think swapoff of the virtual space itself is also necessary,
we really need a failsafe, e.g. a clean way to drop the swap
cache and data, kind of like drop_caches or shrinker fs are
commonly used.
> > > 2. Flash-friendly swap integration (for my use case)
> > >
> > > I've been thinking about the flash-friendly swap concept that
> > > I mentioned before and recently proposed:
> > > (https://lore.kernel.org/linux-mm/aZW0voL4MmnMQlaR@yjaykim-PowerEdge-T330/)
> > >
> > > One of its core functions requires buffering RAM-swapped pages
> > > and writing them sequentially at an appropriate time -- not
> > > immediately, but in proper block-sized units, sequentially.
> > >
> > > This means allocated offsets must essentially be virtual, and
> > > physical offsets need to be managed separately at the actual
> > > write time.
> > >
> > > If we integrate this into the current vswap, we would either
> > > need vswap itself to handle the sequential writes (bypassing
> > > the physical device and receiving pages directly), or swapon
> > > a swap device and have vswap obtain physical offsets from it.
> > > But since those offsets cannot be used directly (due to
> > > buffering and sequential write requirements), they become
> > > virtual too, resulting in:
> > >
> > > virtual -> virtual -> physical
> > >
> > > This triple indirection is not ideal.
> > >
> > > However, if the modularization from point 1 is achieved and
> > > vswap acts as a swap device itself, then we can cleanly
> > > establish a:
> > >
> > > virtual -> physical
> >
> > I read that thread sometimes ago. Some remarks:
> >
> > 1. I think Christoph has a point. Seems like some of your ideas ( are
> > broadly applicable to swap in general. Maybe fixing swap infra
> > generally would make a lot of sense?
>
> Broadly speaking, there are two main ideas:
> 1. Swap I/O buffering (which is also tied to cluster management issues)
> 2. Deduplication
>
> Are you leaning towards the view that these two should be placed in a
> higher layer?
IMHO the swap infra should be doing less, not more, so we can have
more flexible design, and different backends can implement their own
way to manage the data and layer. e.g. Having one backend being
flash friendly and it can do this without caring or affecting other devices
or backends.
> If it goes into ZSWAP, there would definitely be a clear advantage of
> seeing dedup benefits across all swap devices. It's a technically
> interesting area, and I'd like to discuss it in a separate thread if
> I have more ideas or thoughts.
Just branstorm... Why don't we just merge these identical pages like
KSM? Maybe at least zero folios might benefit a lot if we keep them
mapped as RO instead of recording them in swap, seems better in the
long term?
^ permalink raw reply
* [PATCH 0/2] Add support for MAX20830 PMBUS
From: Alexis Czezar Torreno @ 2026-04-14 4:28 UTC (permalink / raw)
To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Jonathan Corbet, Shuah Khan
Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
Alexis Czezar Torreno
This series adds support for the Analog Devices MAX20830 step-down
switching regulator with PMBus interface.
The MAX20830 provides 2.7V to 16V input, 0.4V to 5.8V output, and up
to 30A output current. It supports monitoring of input/output voltage,
output current, and temperature via PMBus.
Datasheet: https://www.analog.com/en/products/max20830.html
Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
Alexis Czezar Torreno (2):
dt-bindings: hwmon: pmbus: add max20830
hwmon: (pmbus/max20830) add driver for max20830
.../bindings/hwmon/pmbus/adi,max20830.yaml | 58 +++++++++++++++++
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/max20830.rst | 48 ++++++++++++++
MAINTAINERS | 9 +++
drivers/hwmon/pmbus/Kconfig | 9 +++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/max20830.c | 74 ++++++++++++++++++++++
7 files changed, 200 insertions(+)
---
base-commit: fb447217c59a13b2fff22d94de2498c185cd9032
change-id: 20260414-dev_max20830-9460b92cf6aa
Best regards,
--
Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
^ permalink raw reply
* [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830
From: Alexis Czezar Torreno @ 2026-04-14 4:28 UTC (permalink / raw)
To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Jonathan Corbet, Shuah Khan
Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
Alexis Czezar Torreno
In-Reply-To: <20260414-dev_max20830-v1-0-210d3f82c571@analog.com>
Add support for MAX20830 step-down DC-DC switching regulator with
PMBus interface. It allows monitoring of input/output voltage,
output current and temperature through the PMBus serial interface.
Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/max20830.rst | 48 ++++++++++++++++++++++++++
MAINTAINERS | 2 ++
drivers/hwmon/pmbus/Kconfig | 9 +++++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/max20830.c | 74 ++++++++++++++++++++++++++++++++++++++++
6 files changed, 135 insertions(+)
diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index 8b655e5d6b68b90c697a52c7bf526e81d370caf7..56f7eb761be76dd627a2f34135abad05203b0582 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -158,6 +158,7 @@ Hardware Monitoring Kernel Drivers
max197
max20730
max20751
+ max20830
max31722
max31730
max31760
diff --git a/Documentation/hwmon/max20830.rst b/Documentation/hwmon/max20830.rst
new file mode 100644
index 0000000000000000000000000000000000000000..b9dffb76059781932d383ed798cecff69e738873
--- /dev/null
+++ b/Documentation/hwmon/max20830.rst
@@ -0,0 +1,48 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver max20830
+======================
+
+Supported chips:
+
+ * Analog Devices MAX20830
+
+ Prefix: 'max20830'
+
+ Addresses scanned: -
+
+ Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max20830.pdf
+
+Author:
+
+ - Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+
+
+Description
+-----------
+
+This driver supports hardware monitoring for Analog Devices MAX20830
+Step-Down Switching Regulator with PMBus Interface.
+
+The MAX20830 is a 2.7V to 16V, 30A fully integrated step-down DC-DC switching
+regulator. Through the PMBus interface, the device can monitor input/output
+voltages, output current and temperature.
+
+The driver is a client driver to the core PMBus driver. Please see
+Documentation/hwmon/pmbus.rst for details on PMBus client drivers.
+
+Sysfs entries
+-------------
+
+================= ========================================
+in1_label "vin"
+in1_input Measured input voltage
+in1_alarm Input voltage alarm
+in2_label "vout1"
+in2_input Measured output voltage
+curr1_label "iout1"
+curr1_input Measured output current
+curr1_alarm Output current alarm
+temp1_input Measured temperature
+temp1_alarm Chip temperature alarm
+================= ========================================
diff --git a/MAINTAINERS b/MAINTAINERS
index 031c743e979521a92ed9ac67915c178ce31727bd..d6a6745e2dae29c3b8f80bbe61c54a2f5ecd9f47 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15585,6 +15585,8 @@ L: linux-hwmon@vger.kernel.org
S: Supported
W: https://ez.analog.com/linux-software-drivers
F: Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
+F: Documentation/hwmon/max20830.rst
+F: drivers/hwmon/pmbus/max20830.c
MAX2175 SDR TUNER DRIVER
M: Ramesh Shanmugasundaram <rashanmu@gmail.com>
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 8f4bff375ecbc355f5ed3400855c2852ec2aa5ef..987705bf45b75b7b91ccc469247909f3c3f53d77 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -365,6 +365,15 @@ config SENSORS_MAX20751
This driver can also be built as a module. If so, the module will
be called max20751.
+config SENSORS_MAX20830
+ tristate "Analog Devices MAX20830"
+ help
+ If you say yes here you get hardware monitoring support for Analog
+ Devices MAX20830.
+
+ This driver can also be built as a module. If so, the module will
+ be called max20830.
+
config SENSORS_MAX31785
tristate "Maxim MAX31785 and compatibles"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 7129b62bc00f8a2e98de14004997752a856dfda2..bc52f930e0825a902a0dd1c9e2b44f2e8d577c35 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_SENSORS_MAX16601) += max16601.o
obj-$(CONFIG_SENSORS_MAX17616) += max17616.o
obj-$(CONFIG_SENSORS_MAX20730) += max20730.o
obj-$(CONFIG_SENSORS_MAX20751) += max20751.o
+obj-$(CONFIG_SENSORS_MAX20830) += max20830.o
obj-$(CONFIG_SENSORS_MAX31785) += max31785.o
obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
obj-$(CONFIG_SENSORS_MAX8688) += max8688.o
diff --git a/drivers/hwmon/pmbus/max20830.c b/drivers/hwmon/pmbus/max20830.c
new file mode 100644
index 0000000000000000000000000000000000000000..bcf60fd948e3437f47267747547142704ae96378
--- /dev/null
+++ b/drivers/hwmon/pmbus/max20830.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hardware monitoring driver for Analog Devices MAX20830
+ *
+ * Copyright (C) 2026 Analog Devices, Inc.
+ */
+
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+static struct pmbus_driver_info max20830_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_IN] = linear,
+ .format[PSC_VOLTAGE_OUT] = linear,
+ .format[PSC_CURRENT_OUT] = linear,
+ .format[PSC_TEMPERATURE] = linear,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
+ PMBUS_HAVE_TEMP |
+ PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
+ PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
+};
+
+static int max20830_probe(struct i2c_client *client)
+{
+ u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+ return -ENODEV;
+
+ ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
+ I2C_SMBUS_BLOCK_MAX, buf);
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret,
+ "Failed to read IC_DEVICE_ID\n");
+
+ buf[ret] = '\0';
+ if (ret < 9 || strncmp(buf + 1, "MAX20830", 8))
+ return dev_err_probe(&client->dev, -ENODEV,
+ "Unsupported device: '%s'\n", buf);
+
+ return pmbus_do_probe(client, &max20830_info);
+}
+
+static const struct i2c_device_id max20830_id[] = {
+ {"max20830"},
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max20830_id);
+
+static const struct of_device_id max20830_of_match[] = {
+ { .compatible = "adi,max20830" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, max20830_of_match);
+
+static struct i2c_driver max20830_driver = {
+ .driver = {
+ .name = "max20830",
+ .of_match_table = max20830_of_match,
+ },
+ .probe = max20830_probe,
+ .id_table = max20830_id,
+};
+
+module_i2c_driver(max20830_driver);
+
+MODULE_AUTHOR("Alexis Czezar Torreno <alexisczezar.torreno@analog.com>");
+MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);
--
2.34.1
^ permalink raw reply related
* [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830
From: Alexis Czezar Torreno @ 2026-04-14 4:28 UTC (permalink / raw)
To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Jonathan Corbet, Shuah Khan
Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
Alexis Czezar Torreno
In-Reply-To: <20260414-dev_max20830-v1-0-210d3f82c571@analog.com>
Add device tree documentation for MAX20830 step-down DC-DC switching
regulator with PMBus interface.
Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
.../bindings/hwmon/pmbus/adi,max20830.yaml | 58 ++++++++++++++++++++++
MAINTAINERS | 7 +++
2 files changed, 65 insertions(+)
diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..b20f3be176615895e70e74bfb2a534d82d124a15
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/pmbus/adi,max20830.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices MAX20830 Step-Down Switching Regulator with PMBus
+
+maintainers:
+ - Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+
+description: |
+ The MAX20830 is a fully integrated step-down DC-DC switching regulator with
+ PMBus interface. It provides 2.7V to 16V input, 0.4V to 5.8V adjustable
+ output, and up to 30A output current. It allows monitoring of input/output
+ voltage, output current and temperature through the PMBus serial interface.
+ Datasheet:
+ https://www.analog.com/en/products/max20830.html
+
+properties:
+ compatible:
+ const: adi,max20830
+
+ reg:
+ maxItems: 1
+
+ vddh-supply:
+ description:
+ Phandle to the regulator that provides the VDDH power supply.
+
+ avdd-supply:
+ description:
+ Phandle to the regulator that provides the AVDD power supply.
+
+ ldoin-supply:
+ description:
+ Optional 2.5V to 5.5V LDO input supply.
+
+required:
+ - compatible
+ - reg
+ - vddh-supply
+
+additionalProperties: false
+
+examples:
+ - |
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ hwmon@30 {
+ compatible = "adi,max20830";
+ reg = <0x30>;
+ vddh-supply = <&vddh>;
+ };
+ };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 0a3991c10ade20dd79cc7d1bf2a1d307ba6bd19d..031c743e979521a92ed9ac67915c178ce31727bd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15579,6 +15579,13 @@ F: Documentation/devicetree/bindings/hwmon/pmbus/adi,max17616.yaml
F: Documentation/hwmon/max17616.rst
F: drivers/hwmon/pmbus/max17616.c
+MAX20830 HARDWARE MONITOR DRIVER
+M: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+L: linux-hwmon@vger.kernel.org
+S: Supported
+W: https://ez.analog.com/linux-software-drivers
+F: Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
+
MAX2175 SDR TUNER DRIVER
M: Ramesh Shanmugasundaram <rashanmu@gmail.com>
L: linux-media@vger.kernel.org
--
2.34.1
^ permalink raw reply related
* [RFC PATCH 0/2] mm/damon/stat: add kdamond_pid parameter
From: SeongJae Park @ 2026-04-14 4:49 UTC (permalink / raw)
Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
Jonathan Corbet, Lorenzo Stoakes, Michal Hocko, Mike Rapoport,
Shuah Khan, Suren Baghdasaryan, Vlastimil Babka, damon, linux-doc,
linux-kernel, linux-mm
DAMON_STAT doesn't provide the pid of its kdamond, unlike DAMON_RECLAIM
and DAMON_LRU_SORT. This makes user-space management of DAMON_STAT
unnecessarily complicated. Provide the information via a new parameter,
namely kdamond_pid, and document it.
SeongJae Park (2):
mm/damon/stat: add a parameter for reading kdamond pid
Docs/admin-guide/mm/damon/stat: document kdamond_pid parameter
Documentation/admin-guide/mm/damon/stat.rst | 7 +++++++
mm/damon/stat.c | 13 +++++++++++++
2 files changed, 20 insertions(+)
base-commit: 5262d0a487d50faeefbca2e4ebbdfbed3f69426e
--
2.47.3
^ permalink raw reply
* [RFC PATCH 2/2] Docs/admin-guide/mm/damon/stat: document kdamond_pid parameter
From: SeongJae Park @ 2026-04-14 4:50 UTC (permalink / raw)
Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
Jonathan Corbet, Lorenzo Stoakes, Michal Hocko, Mike Rapoport,
Shuah Khan, Suren Baghdasaryan, Vlastimil Babka, damon, linux-doc,
linux-kernel, linux-mm
In-Reply-To: <20260414045002.88110-1-sj@kernel.org>
Update DAMON_STAT usage document for newly added kdamond_pid parameter.
Signed-off-by: SeongJae Park <sj@kernel.org>
---
Documentation/admin-guide/mm/damon/stat.rst | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/Documentation/admin-guide/mm/damon/stat.rst b/Documentation/admin-guide/mm/damon/stat.rst
index c4b14daeb2dd6..46c5dd96aa2ed 100644
--- a/Documentation/admin-guide/mm/damon/stat.rst
+++ b/Documentation/admin-guide/mm/damon/stat.rst
@@ -89,3 +89,10 @@ percentiles of the idle time values via this read-only parameter. Reading the
parameter returns 101 idle time values in milliseconds, separated by comma.
Each value represents 0-th, 1st, 2nd, 3rd, ..., 99th and 100th percentile idle
times.
+
+kdamond_pid
+-----------
+
+PID of the DAMON thread.
+
+If DAMON_STAT is enabled, this becomes the PID of the worker thread. Else, -1.
--
2.47.3
^ permalink raw reply related
* [RFC PATCH 0/2] mm/damon/reclaim: support monitoring intervals auto-tuning
From: SeongJae Park @ 2026-04-14 4:52 UTC (permalink / raw)
Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
Jonathan Corbet, Lorenzo Stoakes, Michal Hocko, Mike Rapoport,
Shuah Khan, Suren Baghdasaryan, Vlastimil Babka, damon, linux-doc,
linux-kernel, linux-mm
The monitoring intervals auto-tuning feature of DAMON has proven to be
useful in multiple environments. Add a new DAMON_RECLAIM parameter for
supporting the feature, and update the document for the new parameter.
SeongJae Park (2):
mm/damon/reclaim: add autotune_monitoring_intervals parameter
Docs/admin-guide/mm/damon/reclaim: update for
autotune_monitoring_intervals
.../admin-guide/mm/damon/reclaim.rst | 11 +++++++
mm/damon/reclaim.c | 33 ++++++++++++++++---
2 files changed, 39 insertions(+), 5 deletions(-)
base-commit: 02f9b1619307bbcf7028704a50f6b31909f360ce
--
2.47.3
^ permalink raw reply
* [RFC PATCH 2/2] Docs/admin-guide/mm/damon/reclaim: update for autotune_monitoring_intervals
From: SeongJae Park @ 2026-04-14 4:52 UTC (permalink / raw)
Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
Jonathan Corbet, Lorenzo Stoakes, Michal Hocko, Mike Rapoport,
Shuah Khan, Suren Baghdasaryan, Vlastimil Babka, damon, linux-doc,
linux-kernel, linux-mm
In-Reply-To: <20260414045253.88529-1-sj@kernel.org>
Update DAMON_RECLAIM usage document for the newly added monitoring
intervals auto-tuning enablement parameter.
Signed-off-by: SeongJae Park <sj@kernel.org>
---
Documentation/admin-guide/mm/damon/reclaim.rst | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/Documentation/admin-guide/mm/damon/reclaim.rst b/Documentation/admin-guide/mm/damon/reclaim.rst
index 01a34c215b66f..b14a065586271 100644
--- a/Documentation/admin-guide/mm/damon/reclaim.rst
+++ b/Documentation/admin-guide/mm/damon/reclaim.rst
@@ -85,6 +85,17 @@ identifies the region as cold, and reclaims it.
120 seconds by default.
+autotune_monitoring_intervals
+-----------------------------
+
+If this parameter is set as ``Y``, DAMON_RECLAIM automatically tunes DAMON's
+sampling and aggregation intervals. The auto-tuning aims to capture meaningful
+amount of access events in each DAMON-snapshot, while keeping the sampling
+interval 5 milliseconds in minimum, and 10 seconds in maximum. Setting this as
+``N`` disables the auto-tuning.
+
+Disabled by default.
+
quota_ms
--------
--
2.47.3
^ permalink raw reply related
* [PATCH v4 00/13] Support for Samsung S2MU005 PMIC and its sub-devices
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty, Conor Dooley
S2MU005 is an MFD chip manufactured by Samsung Electronics. This is
found in various devices manufactured by Samsung and others, including
all Exynos 7870 devices. It is known to have the following features:
1. Two LED channels with adjustable brightness for use as a torch, or a
flash strobe.
2. An RGB LED with 8-bit channels. Usually programmed as a notification
indicator.
3. An MUIC, which works with USB micro-B (and USB-C?). For the micro-B
variant though, it measures the ID-GND resistance using an internal
ADC.
4. A charger device, which reports if charger is online, voltage,
resistance, etc.
This patch series implements a lot of these features. Naturally, this
series touches upon a lot of subsystems. The 'parent' is the MFD driver,
so the subsystems have some form of dependency to the MFD driver, so
they are not separable.
Here are the subsystems corresponding to the patch numbers:
dt-bindings - 01, 02, 03, 04, 05
mfd - 05, 06, 07, 08
led - 01, 02, 09, 10, 11
extcon - 03, 12
power - 04, 13
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
Changes in v4:
- Use OF graph to connect charger with MUIC in device tree
- Move DMA coherent mask to all MFD PMICs (André Draszik)
- Modify pointer names for flash/RGB drivers (Lee Jones)
- Use 100-char line wrap for flash/RGB drivers (Lee Jones)
- Revamp LED device initialization in flash driver (Lee Jones)
- Add proper USB 2.0 support in charger driver (Łukasz Lebiedziński)
- Link to v3: https://lore.kernel.org/r/20260225-s2mu005-pmic-v3-0-b4afee947603@disroot.org
Changes in v3:
- Remove "extcon" text from dt-bindings documentation (Rob Herring)
- Add connector for MUIC node
- Fix dt binding errors reported by robh's bot
- Fix kernel test robot const errors
- Remove FIELD_PREP() values in register header file (André Draszik)
- Add max_register, volatile_reg, cache_type (André Draszik)
- Redo [v2 07/12] to NOT store the PMIC revision (André Draszik)
- Add a commit to fix DMA coherent mask in I2C PMICs
- Implement various flow changes in flash LED driver (André Draszik)
- Use device_for_each_child_node_scoped() (André Draszik)
- Fix CFI panic in devm_add_action_or_reset()
- Link to v2: https://lore.kernel.org/r/20260126-s2mu005-pmic-v2-0-78f1a75f547a@disroot.org
Changes in v2:
- Drop [v1 06/13], instead use regmap_irq_chip::get_irq_regs()
- Remove references to driver in devicetree commits (Conor Dooley)
- Propagate errors of sec_pmic_store_rev() (André Draszik)
- Fix documentation language errors (Randy Dunlap)
- Link to v1: https://lore.kernel.org/r/20251114-s2mu005-pmic-v1-0-9e3184d3a0c9@disroot.org
---
Kaustabh Chakraborty (13):
dt-bindings: leds: document Samsung S2M series PMIC flash LED device
dt-bindings: leds: document Samsung S2M series PMIC RGB LED device
dt-bindings: extcon: document Samsung S2M series PMIC extcon device
dt-bindings: power: supply: document Samsung S2M series PMIC charger device
dt-bindings: mfd: s2mps11: add documentation for S2MU005 PMIC
mfd: sec: add support for S2MU005 PMIC
mfd: sec: set DMA coherent mask
mfd: sec: resolve PMIC revision in S2MU005
leds: flash: add support for Samsung S2M series PMIC flash LED device
leds: rgb: add support for Samsung S2M series PMIC RGB LED device
Documentation: leds: document pattern behavior of Samsung S2M series PMIC RGB LEDs
extcon: add support for Samsung S2M series PMIC extcon devices
power: supply: add support for Samsung S2M series PMIC charger device
.../bindings/extcon/samsung,s2mu005-muic.yaml | 39 ++
.../bindings/leds/samsung,s2mu005-flash.yaml | 52 +++
.../bindings/leds/samsung,s2mu005-rgb.yaml | 34 ++
.../devicetree/bindings/mfd/samsung,s2mps11.yaml | 124 +++++-
.../power/supply/samsung,s2mu005-charger.yaml | 39 ++
Documentation/leds/index.rst | 1 +
Documentation/leds/leds-s2m-rgb.rst | 60 +++
drivers/extcon/Kconfig | 10 +
drivers/extcon/Makefile | 1 +
drivers/extcon/extcon-s2m.c | 354 ++++++++++++++++
drivers/leds/flash/Kconfig | 12 +
drivers/leds/flash/Makefile | 1 +
drivers/leds/flash/leds-s2m-flash.c | 357 +++++++++++++++++
drivers/leds/rgb/Kconfig | 11 +
drivers/leds/rgb/Makefile | 1 +
drivers/leds/rgb/leds-s2m-rgb.c | 446 +++++++++++++++++++++
drivers/mfd/sec-common.c | 37 +-
drivers/mfd/sec-i2c.c | 29 ++
drivers/mfd/sec-irq.c | 74 ++++
drivers/power/supply/Kconfig | 11 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/s2m-charger.c | 300 ++++++++++++++
include/linux/mfd/samsung/core.h | 1 +
include/linux/mfd/samsung/irq.h | 66 +++
include/linux/mfd/samsung/s2mu005.h | 332 +++++++++++++++
25 files changed, 2387 insertions(+), 6 deletions(-)
---
base-commit: 1c7cc4904160c6fc6377564140062d68a3dc93a0
change-id: 20251112-s2mu005-pmic-0c67fa6bac3c
Best regards,
--
Kaustabh Chakraborty <kauschluss@disroot.org>
^ permalink raw reply
* [PATCH v4 01/13] dt-bindings: leds: document Samsung S2M series PMIC flash LED device
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty, Conor Dooley
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Certain Samsung S2M series PMICs have a flash LED controller with
two LED channels, and with torch and flash control modes. Document the
devicetree schema for the device.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
.../bindings/leds/samsung,s2mu005-flash.yaml | 52 ++++++++++++++++++++++
1 file changed, 52 insertions(+)
diff --git a/Documentation/devicetree/bindings/leds/samsung,s2mu005-flash.yaml b/Documentation/devicetree/bindings/leds/samsung,s2mu005-flash.yaml
new file mode 100644
index 0000000000000..36051ab20509f
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/samsung,s2mu005-flash.yaml
@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/samsung,s2mu005-flash.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Flash and Torch LED Controller for Samsung S2M series PMICs
+
+maintainers:
+ - Kaustabh Chakraborty <kauschluss@disroot.org>
+
+description: |
+ The Samsung S2M series PMIC flash LED has two led channels (typically
+ as back and front camera flashes), with support for both torch and
+ flash modes.
+
+ This is a part of device tree bindings for S2M and S5M family of Power
+ Management IC (PMIC).
+
+ See also Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml for
+ additional information and example.
+
+properties:
+ compatible:
+ enum:
+ - samsung,s2mu005-flash
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+patternProperties:
+ "^led@[0-1]$":
+ type: object
+ $ref: common.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ reg:
+ enum: [0, 1]
+
+ required:
+ - reg
+
+required:
+ - compatible
+ - "#address-cells"
+ - "#size-cells"
+
+additionalProperties: false
--
2.53.0
^ permalink raw reply related
* [PATCH v4 02/13] dt-bindings: leds: document Samsung S2M series PMIC RGB LED device
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Certain Samsung S2M series PMICs have a three-channel LED device with
independent brightness control for each channel, typically used as
status indicators in mobile phones. Document the devicetree schema for
this device.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
.../bindings/leds/samsung,s2mu005-rgb.yaml | 34 ++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/Documentation/devicetree/bindings/leds/samsung,s2mu005-rgb.yaml b/Documentation/devicetree/bindings/leds/samsung,s2mu005-rgb.yaml
new file mode 100644
index 0000000000000..6806b6d869ff7
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/samsung,s2mu005-rgb.yaml
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/samsung,s2mu005-rgb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RGB LED Controller for Samsung S2M series PMICs
+
+maintainers:
+ - Kaustabh Chakraborty <kauschluss@disroot.org>
+
+description: |
+ The Samsung S2M series PMIC RGB LED is a three-channel LED device with
+ 8-bit brightness control for each channel, typically used as status
+ indicators in mobile phones.
+
+ This is a part of device tree bindings for S2M and S5M family of Power
+ Management IC (PMIC).
+
+ See also Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml for
+ additional information and example.
+
+allOf:
+ - $ref: common.yaml#
+
+properties:
+ compatible:
+ enum:
+ - samsung,s2mu005-rgb
+
+required:
+ - compatible
+
+unevaluatedProperties: false
--
2.53.0
^ permalink raw reply related
* [PATCH v4 03/13] dt-bindings: extcon: document Samsung S2M series PMIC extcon device
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Certain Samsung S2M series PMICs have a MUIC device which reports
various cable states by measuring the ID-GND resistance with an internal
ADC. Document the devicetree schema for this device.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
.../bindings/extcon/samsung,s2mu005-muic.yaml | 39 ++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/Documentation/devicetree/bindings/extcon/samsung,s2mu005-muic.yaml b/Documentation/devicetree/bindings/extcon/samsung,s2mu005-muic.yaml
new file mode 100644
index 0000000000000..e047e8cbc264e
--- /dev/null
+++ b/Documentation/devicetree/bindings/extcon/samsung,s2mu005-muic.yaml
@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/extcon/samsung,s2mu005-muic.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MUIC Device for Samsung S2M series PMICs
+
+maintainers:
+ - Kaustabh Chakraborty <kauschluss@disroot.org>
+
+description: |
+ The Samsung S2M series PMIC MUIC device is a USB port accessory
+ detector. It reports multiple states depending on the ID-GND
+ resistance measured by an internal ADC.
+
+ This is a part of device tree bindings for S2M and S5M family of Power
+ Management IC (PMIC).
+
+ See also Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml for
+ additional information and example.
+
+properties:
+ compatible:
+ enum:
+ - samsung,s2mu005-muic
+
+ connector:
+ $ref: /schemas/connector/usb-connector.yaml#
+
+ port:
+ $ref: /schemas/graph.yaml#/properties/port
+
+required:
+ - compatible
+ - connector
+ - port
+
+additionalProperties: false
--
2.53.0
^ permalink raw reply related
* [PATCH v4 04/13] dt-bindings: power: supply: document Samsung S2M series PMIC charger device
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Certain Samsung S2M series PMICs have a battery charger device which,
among other things, manages power interfacing of the USB port. It may
supply power, as done in USB OTG operation mode, or it may accept power
and redirect it to the battery fuelgauge for charging. Document this
device.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
.../power/supply/samsung,s2mu005-charger.yaml | 39 ++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/Documentation/devicetree/bindings/power/supply/samsung,s2mu005-charger.yaml b/Documentation/devicetree/bindings/power/supply/samsung,s2mu005-charger.yaml
new file mode 100644
index 0000000000000..4ae45165b85fb
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/supply/samsung,s2mu005-charger.yaml
@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/power/supply/samsung,s2mu005-charger.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Battery Charger for Samsung S2M series PMICs
+
+maintainers:
+ - Kaustabh Chakraborty <kauschluss@disroot.org>
+
+description: |
+ The Samsung S2M series PMIC battery charger manages power interfacing
+ of the USB port. It may supply power, as done in USB OTG operation
+ mode, or it may accept power and redirect it to the battery fuelgauge
+ for charging.
+
+ This is a part of device tree bindings for S2M and S5M family of Power
+ Management IC (PMIC).
+
+ See also Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml for
+ additional information and example.
+
+allOf:
+ - $ref: power-supply.yaml#
+
+properties:
+ compatible:
+ enum:
+ - samsung,s2mu005-charger
+
+ port:
+ $ref: /schemas/graph.yaml#/properties/port
+
+required:
+ - compatible
+ - port
+
+unevaluatedProperties: false
--
2.53.0
^ permalink raw reply related
* [PATCH v4 05/13] dt-bindings: mfd: s2mps11: add documentation for S2MU005 PMIC
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Samsung's S2MU005 PMIC includes subdevices for a charger, an MUIC (Micro
USB Interface Controller), and flash and RGB LED controllers.
Since regulators are not supported by this device, unmark this property
as required and instead set this in a per-device basis for ones which
need it.
Add the compatible and documentation for the S2MU005 PMIC. Also, add an
example for nodes for supported sub-devices, i.e. charger, extcon,
flash, and rgb.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
.../devicetree/bindings/mfd/samsung,s2mps11.yaml | 121 ++++++++++++++++++++-
1 file changed, 120 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml b/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
index ac5d0c149796b..d3d305b9aa765 100644
--- a/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
+++ b/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
@@ -26,12 +26,28 @@ properties:
- samsung,s2mps15-pmic
- samsung,s2mpu02-pmic
- samsung,s2mpu05-pmic
+ - samsung,s2mu005-pmic
clocks:
$ref: /schemas/clock/samsung,s2mps11.yaml
description:
Child node describing clock provider.
+ charger:
+ $ref: /schemas/power/supply/samsung,s2mu005-charger.yaml
+ description:
+ Child node describing battery charger device.
+
+ extcon:
+ $ref: /schemas/extcon/samsung,s2mu005-muic.yaml
+ description:
+ Child node describing extcon device.
+
+ flash:
+ $ref: /schemas/leds/samsung,s2mu005-flash.yaml
+ description:
+ Child node describing flash LEDs.
+
interrupts:
maxItems: 1
@@ -43,6 +59,11 @@ properties:
description:
List of child nodes that specify the regulators.
+ rgb:
+ $ref: /schemas/leds/samsung,s2mu005-rgb.yaml
+ description:
+ Child node describing RGB LEDs.
+
samsung,s2mps11-acokb-ground:
description: |
Indicates that ACOKB pin of S2MPS11 PMIC is connected to the ground so
@@ -63,7 +84,6 @@ properties:
required:
- compatible
- reg
- - regulators
additionalProperties: false
@@ -78,6 +98,8 @@ allOf:
regulators:
$ref: /schemas/regulator/samsung,s2mps11.yaml
samsung,s2mps11-wrstbi-ground: false
+ required:
+ - regulators
- if:
properties:
@@ -89,6 +111,8 @@ allOf:
regulators:
$ref: /schemas/regulator/samsung,s2mps13.yaml
samsung,s2mps11-acokb-ground: false
+ required:
+ - regulators
- if:
properties:
@@ -101,6 +125,8 @@ allOf:
$ref: /schemas/regulator/samsung,s2mps14.yaml
samsung,s2mps11-acokb-ground: false
samsung,s2mps11-wrstbi-ground: false
+ required:
+ - regulators
- if:
properties:
@@ -113,6 +139,8 @@ allOf:
$ref: /schemas/regulator/samsung,s2mps15.yaml
samsung,s2mps11-acokb-ground: false
samsung,s2mps11-wrstbi-ground: false
+ required:
+ - regulators
- if:
properties:
@@ -125,6 +153,8 @@ allOf:
$ref: /schemas/regulator/samsung,s2mpu02.yaml
samsung,s2mps11-acokb-ground: false
samsung,s2mps11-wrstbi-ground: false
+ required:
+ - regulators
- if:
properties:
@@ -137,6 +167,18 @@ allOf:
$ref: /schemas/regulator/samsung,s2mpu05.yaml
samsung,s2mps11-acokb-ground: false
samsung,s2mps11-wrstbi-ground: false
+ required:
+ - regulators
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: samsung,s2mu005-pmic
+ then:
+ properties:
+ samsung,s2mps11-acokb-ground: false
+ samsung,s2mps11-wrstbi-ground: false
examples:
- |
@@ -278,3 +320,80 @@ examples:
};
};
};
+
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/leds/common.h>
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pmic@3d {
+ compatible = "samsung,s2mu005-pmic";
+ reg = <0x3d>;
+ interrupt-parent = <&gpa2>;
+ interrupts = <7 IRQ_TYPE_LEVEL_LOW>;
+
+ charger {
+ compatible = "samsung,s2mu005-charger";
+ monitored-battery = <&battery>;
+
+ port {
+ charger_to_muic: endpoint {
+ remote-endpoint = <&muic_to_charger>;
+ };
+ };
+ };
+
+ extcon {
+ compatible = "samsung,s2mu005-muic";
+
+ connector {
+ compatible = "usb-b-connector";
+ label = "micro-USB";
+ type = "micro";
+ };
+
+ port {
+ muic_to_charger: endpoint@0 {
+ reg = <0>;
+ remote-endpoint = <&charger_to_muic>;
+ };
+
+ muic_to_usb: endpoint@1 {
+ reg = <1>;
+ remote-endpoint = <&usb_to_muic>;
+ };
+ };
+ };
+
+ flash {
+ compatible = "samsung,s2mu005-flash";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ led@0 {
+ reg = <0>;
+ label = "back-cam:white:flash";
+ color = <LED_COLOR_ID_WHITE>;
+ function = LED_FUNCTION_FLASH;
+ };
+
+ led@1 {
+ reg = <1>;
+ label = "front-cam:white:flash";
+ color = <LED_COLOR_ID_WHITE>;
+ function = LED_FUNCTION_FLASH;
+ };
+ };
+
+ rgb {
+ compatible = "samsung,s2mu005-rgb";
+ label = "notification:rgb:indicator";
+ color = <LED_COLOR_ID_RGB>;
+ function = LED_FUNCTION_INDICATOR;
+ linux,default-trigger = "pattern";
+ };
+ };
+ };
--
2.53.0
^ permalink raw reply related
* [PATCH v4 06/13] mfd: sec: add support for S2MU005 PMIC
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Samsung's S2MU005 PMIC includes subdevices for a charger, an MUIC (Micro
USB Interface Controller), and flash and RGB LED controllers.
S2MU005's interrupt registers can be properly divided into three regmap
IRQ chips, one each for the charger, flash LEDs, and the MUIC.
Add initial support for S2MU005 in the PMIC driver, along with it's three
interrupt chips.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/mfd/sec-common.c | 16 ++
drivers/mfd/sec-i2c.c | 29 ++++
drivers/mfd/sec-irq.c | 74 ++++++++
include/linux/mfd/samsung/core.h | 1 +
include/linux/mfd/samsung/irq.h | 66 ++++++++
include/linux/mfd/samsung/s2mu005.h | 327 ++++++++++++++++++++++++++++++++++++
6 files changed, 513 insertions(+)
diff --git a/drivers/mfd/sec-common.c b/drivers/mfd/sec-common.c
index bd8b5f9686892..b3268516bf75e 100644
--- a/drivers/mfd/sec-common.c
+++ b/drivers/mfd/sec-common.c
@@ -105,6 +105,18 @@ static const struct mfd_cell s2mpu05_devs[] = {
MFD_CELL_RES("s2mps15-rtc", s2mpu05_rtc_resources),
};
+static const struct resource s2mu005_muic_resources[] = {
+ DEFINE_RES_IRQ_NAMED(S2MU005_IRQ_MUIC_ATTACH, "attach"),
+ DEFINE_RES_IRQ_NAMED(S2MU005_IRQ_MUIC_DETACH, "detach"),
+};
+
+static const struct mfd_cell s2mu005_devs[] = {
+ MFD_CELL_OF("s2mu005-charger", NULL, NULL, 0, 0, "samsung,s2mu005-charger"),
+ MFD_CELL_OF("s2mu005-flash", NULL, NULL, 0, 0, "samsung,s2mu005-flash"),
+ MFD_CELL_OF("s2mu005-muic", s2mu005_muic_resources, NULL, 0, 0, "samsung,s2mu005-muic"),
+ MFD_CELL_OF("s2mu005-rgb", NULL, NULL, 0, 0, "samsung,s2mu005-rgb"),
+};
+
static void sec_pmic_dump_rev(struct sec_pmic_dev *sec_pmic)
{
unsigned int val;
@@ -250,6 +262,10 @@ int sec_pmic_probe(struct device *dev, int device_type, unsigned int irq,
sec_devs = s2mpu05_devs;
num_sec_devs = ARRAY_SIZE(s2mpu05_devs);
break;
+ case S2MU005:
+ sec_devs = s2mu005_devs;
+ num_sec_devs = ARRAY_SIZE(s2mu005_devs);
+ break;
default:
return dev_err_probe(sec_pmic->dev, -EINVAL,
"Unsupported device type %d\n",
diff --git a/drivers/mfd/sec-i2c.c b/drivers/mfd/sec-i2c.c
index 3132b849b4bc4..d8609886fcc80 100644
--- a/drivers/mfd/sec-i2c.c
+++ b/drivers/mfd/sec-i2c.c
@@ -17,6 +17,7 @@
#include <linux/mfd/samsung/s2mps14.h>
#include <linux/mfd/samsung/s2mps15.h>
#include <linux/mfd/samsung/s2mpu02.h>
+#include <linux/mfd/samsung/s2mu005.h>
#include <linux/mfd/samsung/s5m8767.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
@@ -66,6 +67,19 @@ static bool s2mpu02_volatile(struct device *dev, unsigned int reg)
}
}
+static bool s2mu005_volatile(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case S2MU005_REG_CHGR_INT1M:
+ case S2MU005_REG_FLED_INT1M:
+ case S2MU005_REG_MUIC_INT1M:
+ case S2MU005_REG_MUIC_INT2M:
+ return false;
+ default:
+ return true;
+ }
+}
+
static const struct regmap_config s2dos05_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
@@ -130,6 +144,15 @@ static const struct regmap_config s2mpu05_regmap_config = {
.val_bits = 8,
};
+static const struct regmap_config s2mu005_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = S2MU005_REG_MUIC_LDOADC_H,
+ .volatile_reg = s2mu005_volatile,
+ .cache_type = REGCACHE_FLAT_S,
+};
+
static const struct regmap_config s5m8767_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
@@ -203,6 +226,11 @@ static const struct sec_pmic_i2c_platform_data s2mpu05_data = {
.device_type = S2MPU05,
};
+static const struct sec_pmic_i2c_platform_data s2mu005_data = {
+ .regmap_cfg = &s2mu005_regmap_config,
+ .device_type = S2MU005,
+};
+
static const struct sec_pmic_i2c_platform_data s5m8767_data = {
.regmap_cfg = &s5m8767_regmap_config,
.device_type = S5M8767X,
@@ -217,6 +245,7 @@ static const struct of_device_id sec_pmic_i2c_of_match[] = {
{ .compatible = "samsung,s2mps15-pmic", .data = &s2mps15_data, },
{ .compatible = "samsung,s2mpu02-pmic", .data = &s2mpu02_data, },
{ .compatible = "samsung,s2mpu05-pmic", .data = &s2mpu05_data, },
+ { .compatible = "samsung,s2mu005-pmic", .data = &s2mu005_data, },
{ .compatible = "samsung,s5m8767-pmic", .data = &s5m8767_data, },
{ },
};
diff --git a/drivers/mfd/sec-irq.c b/drivers/mfd/sec-irq.c
index 133188391f7c2..91a2922463fb6 100644
--- a/drivers/mfd/sec-irq.c
+++ b/drivers/mfd/sec-irq.c
@@ -16,6 +16,7 @@
#include <linux/mfd/samsung/s2mps14.h>
#include <linux/mfd/samsung/s2mpu02.h>
#include <linux/mfd/samsung/s2mpu05.h>
+#include <linux/mfd/samsung/s2mu005.h>
#include <linux/mfd/samsung/s5m8767.h>
#include <linux/regmap.h>
#include "sec-core.h"
@@ -223,6 +224,65 @@ static const struct regmap_irq s2mpu05_irqs[] = {
REGMAP_IRQ_REG(S2MPU05_IRQ_TSD, 2, S2MPU05_IRQ_TSD_MASK),
};
+static const struct regmap_irq s2mu005_irqs[] = {
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_DETBAT, 0, S2MU005_IRQ_CHGR_DETBAT_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_BAT, 0, S2MU005_IRQ_CHGR_BAT_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_IVR, 0, S2MU005_IRQ_CHGR_IVR_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_EVENT, 0, S2MU005_IRQ_CHGR_EVENT_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_CHG, 0, S2MU005_IRQ_CHGR_CHG_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_VMID, 0, S2MU005_IRQ_CHGR_VMID_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_WCIN, 0, S2MU005_IRQ_CHGR_WCIN_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_CHGR_VBUS, 0, S2MU005_IRQ_CHGR_VBUS_MASK),
+
+ REGMAP_IRQ_REG(S2MU005_IRQ_FLED_LBPROT, 1, S2MU005_IRQ_FLED_LBPROT_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_FLED_OPENCH2, 1, S2MU005_IRQ_FLED_OPENCH2_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_FLED_OPENCH1, 1, S2MU005_IRQ_FLED_OPENCH1_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_FLED_SHORTCH2, 1, S2MU005_IRQ_FLED_SHORTCH2_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_FLED_SHORTCH1, 1, S2MU005_IRQ_FLED_SHORTCH1_MASK),
+
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_ATTACH, 2, S2MU005_IRQ_MUIC_ATTACH_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_DETACH, 2, S2MU005_IRQ_MUIC_DETACH_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_KP, 2, S2MU005_IRQ_MUIC_KP_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_LKP, 2, S2MU005_IRQ_MUIC_LKP_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_LKR, 2, S2MU005_IRQ_MUIC_LKR_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_RIDCHG, 2, S2MU005_IRQ_MUIC_RIDCHG_MASK),
+
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_VBUSON, 3, S2MU005_IRQ_MUIC_VBUSON_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_RSVD, 3, S2MU005_IRQ_MUIC_RSVD_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_ADC, 3, S2MU005_IRQ_MUIC_ADC_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_STUCK, 3, S2MU005_IRQ_MUIC_STUCK_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_STUCKRCV, 3, S2MU005_IRQ_MUIC_STUCKRCV_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_MHDL, 3, S2MU005_IRQ_MUIC_MHDL_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_AVCHG, 3, S2MU005_IRQ_MUIC_AVCHG_MASK),
+ REGMAP_IRQ_REG(S2MU005_IRQ_MUIC_VBUSOFF, 3, S2MU005_IRQ_MUIC_VBUSOFF_MASK),
+};
+
+static unsigned int s2mu005_irq_get_reg(struct regmap_irq_chip_data *data,
+ unsigned int base, int index)
+{
+ const unsigned int irqf_regs[] = {
+ S2MU005_REG_CHGR_INT1,
+ S2MU005_REG_FLED_INT1,
+ S2MU005_REG_MUIC_INT1,
+ S2MU005_REG_MUIC_INT2,
+ };
+ const unsigned int mask_regs[] = {
+ S2MU005_REG_CHGR_INT1M,
+ S2MU005_REG_FLED_INT1M,
+ S2MU005_REG_MUIC_INT1M,
+ S2MU005_REG_MUIC_INT2M,
+ };
+
+ switch (base) {
+ case S2MU005_REG_CHGR_INT1:
+ return irqf_regs[index];
+ case S2MU005_REG_CHGR_INT1M:
+ return mask_regs[index];
+ }
+
+ return base;
+}
+
static const struct regmap_irq s5m8767_irqs[] = {
REGMAP_IRQ_REG(S5M8767_IRQ_PWRR, 0, S5M8767_IRQ_PWRR_MASK),
REGMAP_IRQ_REG(S5M8767_IRQ_PWRF, 0, S5M8767_IRQ_PWRF_MASK),
@@ -337,6 +397,17 @@ static const struct regmap_irq_chip s2mpu05_irq_chip = {
.ack_base = S2MPU05_REG_INT1,
};
+static const struct regmap_irq_chip s2mu005_irq_chip = {
+ .name = "s2mu005",
+ .irqs = s2mu005_irqs,
+ .num_irqs = ARRAY_SIZE(s2mu005_irqs),
+ .num_regs = 4,
+ .status_base = S2MU005_REG_CHGR_INT1,
+ .mask_base = S2MU005_REG_CHGR_INT1M,
+ .ack_base = S2MU005_REG_CHGR_INT1,
+ .get_irq_reg = s2mu005_irq_get_reg,
+};
+
static const struct regmap_irq_chip s5m8767_irq_chip = {
.name = "s5m8767",
.irqs = s5m8767_irqs,
@@ -442,6 +513,9 @@ struct regmap_irq_chip_data *sec_irq_init(struct sec_pmic_dev *sec_pmic)
case S2MPU05:
sec_irq_chip = &s2mpu05_irq_chip;
break;
+ case S2MU005:
+ sec_irq_chip = &s2mu005_irq_chip;
+ break;
default:
return dev_err_ptr_probe(sec_pmic->dev, -EINVAL, "Unsupported device type %d\n",
sec_pmic->device_type);
diff --git a/include/linux/mfd/samsung/core.h b/include/linux/mfd/samsung/core.h
index 4480c631110a6..6191f409de945 100644
--- a/include/linux/mfd/samsung/core.h
+++ b/include/linux/mfd/samsung/core.h
@@ -47,6 +47,7 @@ enum sec_device_type {
S2MPS15X,
S2MPU02,
S2MPU05,
+ S2MU005,
};
/**
diff --git a/include/linux/mfd/samsung/irq.h b/include/linux/mfd/samsung/irq.h
index 6eab95de6fa83..19d0f0e12944f 100644
--- a/include/linux/mfd/samsung/irq.h
+++ b/include/linux/mfd/samsung/irq.h
@@ -408,6 +408,72 @@ enum s2mpu05_irq {
#define S2MPU05_IRQ_INT140C_MASK BIT(1)
#define S2MPU05_IRQ_TSD_MASK BIT(2)
+enum s2mu005_irq {
+ S2MU005_IRQ_CHGR_DETBAT,
+ S2MU005_IRQ_CHGR_BAT,
+ S2MU005_IRQ_CHGR_IVR,
+ S2MU005_IRQ_CHGR_EVENT,
+ S2MU005_IRQ_CHGR_CHG,
+ S2MU005_IRQ_CHGR_VMID,
+ S2MU005_IRQ_CHGR_WCIN,
+ S2MU005_IRQ_CHGR_VBUS,
+
+ S2MU005_IRQ_FLED_LBPROT,
+ S2MU005_IRQ_FLED_OPENCH2,
+ S2MU005_IRQ_FLED_OPENCH1,
+ S2MU005_IRQ_FLED_SHORTCH2,
+ S2MU005_IRQ_FLED_SHORTCH1,
+
+ S2MU005_IRQ_MUIC_ATTACH,
+ S2MU005_IRQ_MUIC_DETACH,
+ S2MU005_IRQ_MUIC_KP,
+ S2MU005_IRQ_MUIC_LKP,
+ S2MU005_IRQ_MUIC_LKR,
+ S2MU005_IRQ_MUIC_RIDCHG,
+
+ S2MU005_IRQ_MUIC_VBUSON,
+ S2MU005_IRQ_MUIC_RSVD,
+ S2MU005_IRQ_MUIC_ADC,
+ S2MU005_IRQ_MUIC_STUCK,
+ S2MU005_IRQ_MUIC_STUCKRCV,
+ S2MU005_IRQ_MUIC_MHDL,
+ S2MU005_IRQ_MUIC_AVCHG,
+ S2MU005_IRQ_MUIC_VBUSOFF,
+
+ S2MU005_IRQ_NR,
+};
+
+#define S2MU005_IRQ_CHGR_DETBAT_MASK BIT(0)
+#define S2MU005_IRQ_CHGR_BAT_MASK BIT(1)
+#define S2MU005_IRQ_CHGR_IVR_MASK BIT(2)
+#define S2MU005_IRQ_CHGR_EVENT_MASK BIT(3)
+#define S2MU005_IRQ_CHGR_CHG_MASK BIT(4)
+#define S2MU005_IRQ_CHGR_VMID_MASK BIT(5)
+#define S2MU005_IRQ_CHGR_WCIN_MASK BIT(6)
+#define S2MU005_IRQ_CHGR_VBUS_MASK BIT(7)
+
+#define S2MU005_IRQ_FLED_LBPROT_MASK BIT(2)
+#define S2MU005_IRQ_FLED_OPENCH2_MASK BIT(4)
+#define S2MU005_IRQ_FLED_OPENCH1_MASK BIT(5)
+#define S2MU005_IRQ_FLED_SHORTCH2_MASK BIT(6)
+#define S2MU005_IRQ_FLED_SHORTCH1_MASK BIT(7)
+
+#define S2MU005_IRQ_MUIC_ATTACH_MASK BIT(0)
+#define S2MU005_IRQ_MUIC_DETACH_MASK BIT(1)
+#define S2MU005_IRQ_MUIC_KP_MASK BIT(2)
+#define S2MU005_IRQ_MUIC_LKP_MASK BIT(3)
+#define S2MU005_IRQ_MUIC_LKR_MASK BIT(4)
+#define S2MU005_IRQ_MUIC_RIDCHG_MASK BIT(5)
+
+#define S2MU005_IRQ_MUIC_VBUSON_MASK BIT(0)
+#define S2MU005_IRQ_MUIC_RSVD_MASK BIT(1)
+#define S2MU005_IRQ_MUIC_ADC_MASK BIT(2)
+#define S2MU005_IRQ_MUIC_STUCK_MASK BIT(3)
+#define S2MU005_IRQ_MUIC_STUCKRCV_MASK BIT(4)
+#define S2MU005_IRQ_MUIC_MHDL_MASK BIT(5)
+#define S2MU005_IRQ_MUIC_AVCHG_MASK BIT(6)
+#define S2MU005_IRQ_MUIC_VBUSOFF_MASK BIT(7)
+
enum s5m8767_irq {
S5M8767_IRQ_PWRR,
S5M8767_IRQ_PWRF,
diff --git a/include/linux/mfd/samsung/s2mu005.h b/include/linux/mfd/samsung/s2mu005.h
new file mode 100644
index 0000000000000..07f4ae664950d
--- /dev/null
+++ b/include/linux/mfd/samsung/s2mu005.h
@@ -0,0 +1,327 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd
+ * Copyright (c) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ */
+
+#ifndef __LINUX_MFD_S2MU005_H
+#define __LINUX_MFD_S2MU005_H
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+
+/* S2MU005 registers */
+enum s2mu005_reg {
+ S2MU005_REG_CHGR_INT1,
+ S2MU005_REG_CHGR_INT1M,
+
+ S2MU005_REG_FLED_INT1,
+ S2MU005_REG_FLED_INT1M,
+
+ S2MU005_REG_MUIC_INT1,
+ S2MU005_REG_MUIC_INT2,
+ S2MU005_REG_MUIC_INT1M,
+ S2MU005_REG_MUIC_INT2M,
+
+ S2MU005_REG_CHGR_STATUS0,
+ S2MU005_REG_CHGR_STATUS1,
+ S2MU005_REG_CHGR_STATUS2,
+ S2MU005_REG_CHGR_STATUS3,
+ S2MU005_REG_CHGR_STATUS4,
+ S2MU005_REG_CHGR_STATUS5,
+ S2MU005_REG_CHGR_CTRL0,
+ S2MU005_REG_CHGR_CTRL1,
+ S2MU005_REG_CHGR_CTRL2,
+ S2MU005_REG_CHGR_CTRL3,
+ S2MU005_REG_CHGR_CTRL4,
+ S2MU005_REG_CHGR_CTRL5,
+ S2MU005_REG_CHGR_CTRL6,
+ S2MU005_REG_CHGR_CTRL7,
+ S2MU005_REG_CHGR_CTRL8,
+ S2MU005_REG_CHGR_CTRL9,
+ S2MU005_REG_CHGR_CTRL10,
+ S2MU005_REG_CHGR_CTRL11,
+ S2MU005_REG_CHGR_CTRL12,
+ S2MU005_REG_CHGR_CTRL13,
+ S2MU005_REG_CHGR_CTRL14,
+ S2MU005_REG_CHGR_CTRL15,
+ S2MU005_REG_CHGR_CTRL16,
+ S2MU005_REG_CHGR_CTRL17,
+ S2MU005_REG_CHGR_CTRL18,
+ S2MU005_REG_CHGR_CTRL19,
+ S2MU005_REG_CHGR_TEST0,
+ S2MU005_REG_CHGR_TEST1,
+ S2MU005_REG_CHGR_TEST2,
+ S2MU005_REG_CHGR_TEST3,
+ S2MU005_REG_CHGR_TEST4,
+ S2MU005_REG_CHGR_TEST5,
+ S2MU005_REG_CHGR_TEST6,
+ S2MU005_REG_CHGR_TEST7,
+ S2MU005_REG_CHGR_TEST8,
+ S2MU005_REG_CHGR_TEST9,
+ S2MU005_REG_CHGR_TEST10,
+
+ S2MU005_REG_FLED_STATUS,
+ S2MU005_REG_FLED_CH0_CTRL0,
+ S2MU005_REG_FLED_CH0_CTRL1,
+ S2MU005_REG_FLED_CH0_CTRL2,
+ S2MU005_REG_FLED_CH0_CTRL3,
+ S2MU005_REG_FLED_CH1_CTRL0,
+ S2MU005_REG_FLED_CH1_CTRL1,
+ S2MU005_REG_FLED_CH1_CTRL2,
+ S2MU005_REG_FLED_CH1_CTRL3,
+ S2MU005_REG_FLED_CTRL0,
+ S2MU005_REG_FLED_CTRL1,
+ S2MU005_REG_FLED_CTRL2,
+ S2MU005_REG_FLED_CTRL3,
+ S2MU005_REG_FLED_CTRL4,
+ S2MU005_REG_FLED_CTRL5,
+ S2MU005_REG_FLED_CTRL6,
+
+ S2MU005_REG_RGB_EN,
+ S2MU005_REG_RGB_CH0_CTRL,
+ S2MU005_REG_RGB_CH1_CTRL,
+ S2MU005_REG_RGB_CH2_CTRL,
+ S2MU005_REG_RGB_CH0_RAMP,
+ S2MU005_REG_RGB_CH0_STAY,
+ S2MU005_REG_RGB_CH1_RAMP,
+ S2MU005_REG_RGB_CH1_STAY,
+ S2MU005_REG_RGB_CH2_RAMP,
+ S2MU005_REG_RGB_CH2_STAY,
+ S2MU005_REG_RGB_TEST0,
+ S2MU005_REG_RGB_CTRL0,
+
+ S2MU005_REG_MUIC_ADC,
+ S2MU005_REG_MUIC_DEV1,
+ S2MU005_REG_MUIC_DEV2,
+ S2MU005_REG_MUIC_DEV3,
+ S2MU005_REG_MUIC_BUTTON1,
+ S2MU005_REG_MUIC_BUTTON2,
+ S2MU005_REG_MUIC_RESET,
+ S2MU005_REG_MUIC_CHGTYPE,
+ S2MU005_REG_MUIC_DEVAPPLE,
+ S2MU005_REG_MUIC_BCDRESCAN,
+ S2MU005_REG_MUIC_TEST1,
+ S2MU005_REG_MUIC_TEST2,
+ S2MU005_REG_MUIC_TEST3,
+
+ S2MU005_REG_ID = 0x73,
+
+ S2MU005_REG_MUIC_CTRL1 = 0xb2,
+ S2MU005_REG_MUIC_TIMERSET1,
+ S2MU005_REG_MUIC_TIMERSET2,
+ S2MU005_REG_MUIC_SWCTRL,
+ S2MU005_REG_MUIC_TIMERSET3,
+ S2MU005_REG_MUIC_CTRL2,
+ S2MU005_REG_MUIC_CTRL3,
+
+ S2MU005_REG_MUIC_LDOADC_L = 0xbf,
+ S2MU005_REG_MUIC_LDOADC_H,
+};
+
+#define S2MU005_REG_FLED_CH_CTRL0(x) (S2MU005_REG_FLED_CH0_CTRL0 + 4 * (x))
+#define S2MU005_REG_FLED_CH_CTRL1(x) (S2MU005_REG_FLED_CH0_CTRL1 + 4 * (x))
+#define S2MU005_REG_FLED_CH_CTRL2(x) (S2MU005_REG_FLED_CH0_CTRL2 + 4 * (x))
+#define S2MU005_REG_FLED_CH_CTRL3(x) (S2MU005_REG_FLED_CH0_CTRL3 + 4 * (x))
+
+#define S2MU005_REG_RGB_CH_CTRL(x) (S2MU005_REG_RGB_CH0_CTRL + 1 * (x))
+#define S2MU005_REG_RGB_CH_RAMP(x) (S2MU005_REG_RGB_CH0_RAMP + 2 * (x))
+#define S2MU005_REG_RGB_CH_STAY(x) (S2MU005_REG_RGB_CH0_STAY + 2 * (x))
+
+/* S2MU005_REG_CHGR_STATUS0 */
+#define S2MU005_CHGR_VBUS BIT(7)
+#define S2MU005_CHGR_WCIN BIT(6)
+#define S2MU005_CHGR_VMID BIT(5)
+#define S2MU005_CHGR_CHG BIT(4)
+#define S2MU005_CHGR_STAT GENMASK(3, 0)
+
+#define S2MU005_CHGR_STAT_DONE 8
+#define S2MU005_CHGR_STAT_TOPOFF 7
+#define S2MU005_CHGR_STAT_DONE_FLAG 6
+#define S2MU005_CHGR_STAT_CV 5
+#define S2MU005_CHGR_STAT_CC 4
+#define S2MU005_CHGR_STAT_COOL_CHG 3
+#define S2MU005_CHGR_STAT_PRE_CHG 2
+
+/* S2MU005_REG_CHGR_STATUS1 */
+#define S2MU005_CHGR_DETBAT BIT(7)
+#define S2MU005_CHGR_VBUS_OVP GENMASK(6, 4)
+
+#define S2MU005_CHGR_VBUS_OVP_OVERVOLT 2
+
+/* S2MU005_REG_CHGR_STATUS2 */
+#define S2MU005_CHGR_BAT GENMASK(6, 4)
+
+#define S2MU005_CHGR_BAT_VOLT_DET 7
+#define S2MU005_CHGR_BAT_FAST_CHG_DET 6
+#define S2MU005_CHGR_BAT_COOL_CHG_DET 5
+#define S2MU005_CHGR_BAT_LOW_CHG 2
+#define S2MU005_CHGR_BAT_SELF_DISCHG 1
+#define S2MU005_CHGR_BAT_OVP_DET 0
+
+/* S2MU005_REG_CHGR_STATUS3 */
+#define S2MU005_CHGR_EVT GENMASK(3, 0)
+
+#define S2MU005_CHGR_EVT_WDT_RST 6
+#define S2MU005_CHGR_EVT_WDT_SUSP 5
+#define S2MU005_CHGR_EVT_VSYS_VUVLO 4
+#define S2MU005_CHGR_EVT_VSYS_VOVP 3
+#define S2MU005_CHGR_EVT_THERM_FOLDBACK 2
+#define S2MU005_CHGR_EVT_THERM_SHUTDOWN 1
+
+/* S2MU005_REG_CHGR_CTRL0 */
+#define S2MU005_CHGR_CHG_EN BIT(4)
+#define S2MU005_CHGR_OP_MODE GENMASK(2, 0)
+
+#define S2MU005_CHGR_OP_MODE_OTG BIT(2)
+#define S2MU005_CHGR_OP_MODE_CHG BIT(1)
+
+/* S2MU005_REG_CHGR_CTRL1 */
+#define S2MU005_CHGR_VIN_DROP GENMASK(6, 4)
+
+/* S2MU005_REG_CHGR_CTRL2 */
+#define S2MU005_CHGR_IN_CURR_LIM GENMASK(5, 0)
+
+/* S2MU005_REG_CHGR_CTRL4 */
+#define S2MU005_CHGR_OTG_OCP_ON BIT(5)
+#define S2MU005_CHGR_OTG_OCP_OFF BIT(4)
+#define S2MU005_CHGR_OTG_OCP GENMASK(3, 2)
+
+/* S2MU005_REG_CHGR_CTRL5 */
+#define S2MU005_CHGR_VMID_BOOST GENMASK(4, 0)
+
+/* S2MU005_REG_CHGR_CTRL6 */
+#define S2MU005_CHGR_COOL_CHG_CURR GENMASK(5, 0)
+
+/* S2MU005_REG_CHGR_CTRL7 */
+#define S2MU005_CHGR_FAST_CHG_CURR GENMASK(5, 0)
+
+/* S2MU005_REG_CHGR_CTRL8 */
+#define S2MU005_CHGR_VF_VBAT GENMASK(6, 1)
+
+/* S2MU005_REG_CHGR_CTRL10 */
+#define S2MU005_CHGR_TOPOFF_CURR(x) (GENMASK(3, 0) << 4 * (x))
+
+/* S2MU005_REG_CHGR_CTRL11 */
+#define S2MU005_CHGR_OSC_BOOST GENMASK(6, 5)
+#define S2MU005_CHGR_OSC_BUCK GENMASK(4, 3)
+
+/* S2MU005_REG_CHGR_CTRL12 */
+#define S2MU005_CHGR_WDT GENMASK(2, 0)
+
+#define S2MU005_CHGR_WDT_ON BIT(2)
+#define S2MU005_CHGR_WDT_OFF BIT(1)
+
+/* S2MU005_REG_CHGR_CTRL15 */
+#define S2MU005_CHGR_OTG_EN GENMASK(3, 2)
+
+/* S2MU005_REG_FLED_STATUS */
+#define S2MU005_FLED_FLASH_STATUS(x) (BIT(7) >> 2 * (x))
+#define S2MU005_FLED_TORCH_STATUS(x) (BIT(6) >> 2 * (x))
+
+/* S2MU005_REG_FLED_CHx_CTRL0 */
+#define S2MU005_FLED_FLASH_IOUT GENMASK(3, 0)
+
+/* S2MU005_REG_FLED_CHx_CTRL1 */
+#define S2MU005_FLED_TORCH_IOUT GENMASK(3, 0)
+
+/* S2MU005_REG_FLED_CHx_CTRL2 */
+#define S2MU005_FLED_TORCH_TIMEOUT GENMASK(3, 0)
+
+/* S2MU005_REG_FLED_CHx_CTRL3 */
+#define S2MU005_FLED_FLASH_TIMEOUT GENMASK(3, 0)
+
+/* S2MU005_REG_FLED_CTRL1 */
+#define S2MU005_FLED_CH_EN BIT(7)
+
+/*
+ * S2MU005_REG_FLED_CTRL4 - Rev. EVT0
+ * S2MU005_REG_FLED_CTRL6 - Rev. EVT1 and later
+ */
+#define S2MU005_FLED_FLASH_EN(x) (GENMASK(7, 6) >> 4 * (x))
+#define S2MU005_FLED_TORCH_EN(x) (GENMASK(5, 4) >> 4 * (x))
+
+/* S2MU005_REG_RGB_EN */
+#define S2MU005_RGB_RESET BIT(6)
+#define S2MU005_RGB_SLOPE GENMASK(5, 0)
+
+#define S2MU005_RGB_SLOPE_CONST (BIT(4) | BIT(2) | BIT(0))
+#define S2MU005_RGB_SLOPE_SMOOTH (BIT(5) | BIT(3) | BIT(1))
+
+/* S2MU005_REG_RGB_CHx_RAMP */
+#define S2MU005_RGB_CH_RAMP_UP GENMASK(7, 4)
+#define S2MU005_RGB_CH_RAMP_DN GENMASK(3, 0)
+
+/* S2MU005_REG_RGB_CHx_STAY */
+#define S2MU005_RGB_CH_STAY_HI GENMASK(7, 4)
+#define S2MU005_RGB_CH_STAY_LO GENMASK(3, 0)
+
+/* S2MU005_REG_MUIC_DEV1 */
+#define S2MU005_MUIC_OTG BIT(7)
+#define S2MU005_MUIC_DCP BIT(6)
+#define S2MU005_MUIC_CDP BIT(5)
+#define S2MU005_MUIC_T1_T2_CHG BIT(4)
+#define S2MU005_MUIC_UART BIT(3)
+#define S2MU005_MUIC_SDP BIT(2)
+#define S2MU005_MUIC_LANHUB BIT(1)
+#define S2MU005_MUIC_AUDIO BIT(0)
+
+/* S2MU005_REG_MUIC_DEV2 */
+#define S2MU005_MUIC_SDP_1P8S BIT(7)
+#define S2MU005_MUIC_AV BIT(6)
+#define S2MU005_MUIC_TTY BIT(5)
+#define S2MU005_MUIC_PPD BIT(4)
+#define S2MU005_MUIC_JIG_UART_OFF BIT(3)
+#define S2MU005_MUIC_JIG_UART_ON BIT(2)
+#define S2MU005_MUIC_JIG_USB_OFF BIT(1)
+#define S2MU005_MUIC_JIG_USB_ON BIT(0)
+
+/* S2MU005_REG_MUIC_DEV3 */
+#define S2MU005_MUIC_U200_CHG BIT(7)
+#define S2MU005_MUIC_VBUS_AV BIT(4)
+#define S2MU005_MUIC_VBUS_R255 BIT(1)
+#define S2MU005_MUIC_MHL BIT(0)
+
+/* S2MU005_REG_MUIC_DEVAPPLE */
+#define S2MU005_MUIC_APPLE_CHG_0P5A BIT(7)
+#define S2MU005_MUIC_APPLE_CHG_1P0A BIT(6)
+#define S2MU005_MUIC_APPLE_CHG_2P0A BIT(5)
+#define S2MU005_MUIC_APPLE_CHG_2P4A BIT(4)
+#define S2MU005_MUIC_SDP_DCD_OUT BIT(3)
+#define S2MU005_MUIC_RID_WAKEUP BIT(2)
+#define S2MU005_MUIC_VBUS_WAKEUP BIT(1)
+#define S2MU005_MUIC_BCV1P2_OR_OPEN BIT(0)
+
+/* S2MU005_REG_ID */
+#define S2MU005_ID_MASK GENMASK(3, 0)
+
+/* S2MU005_REG_MUIC_SWCTRL */
+#define S2MU005_MUIC_DM_DP GENMASK(7, 2)
+#define S2MU005_MUIC_JIG BIT(0)
+
+#define S2MU005_MUIC_DM_DP_UART 0x12
+#define S2MU005_MUIC_DM_DP_USB 0x09
+
+/* S2MU005_REG_MUIC_CTRL1 */
+#define S2MU005_MUIC_OPEN BIT(4)
+#define S2MU005_MUIC_RAW_DATA BIT(3)
+#define S2MU005_MUIC_MAN_SW BIT(2)
+#define S2MU005_MUIC_WAIT BIT(1)
+#define S2MU005_MUIC_IRQ BIT(0)
+
+/* S2MU005_REG_MUIC_CTRL3 */
+#define S2MU005_MUIC_ONESHOT_ADC BIT(2)
+
+/* S2MU005_REG_MUIC_LDOADC_L and S2MU005_REG_MUIC_LDOADC_H */
+#define S2MU005_MUIC_VSET GENMASK(4, 0)
+
+#define S2MU005_MUIC_VSET_3P0V 0x1f
+#define S2MU005_MUIC_VSET_2P6V 0x0e
+#define S2MU005_MUIC_VSET_2P4V 0x0c
+#define S2MU005_MUIC_VSET_2P2V 0x0a
+#define S2MU005_MUIC_VSET_2P0V 0x08
+#define S2MU005_MUIC_VSET_1P5V 0x03
+#define S2MU005_MUIC_VSET_1P4V 0x02
+#define S2MU005_MUIC_VSET_1P2V 0x00
+
+#endif /* __LINUX_MFD_S2MU005_H */
--
2.53.0
^ permalink raw reply related
* [PATCH v4 07/13] mfd: sec: set DMA coherent mask
From: Kaustabh Chakraborty @ 2026-04-14 6:32 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Kernel logs are filled with "DMA mask not set" messages for every
sub-device. The device does not use DMA for communication, so these
messages are useless. Disable the coherent DMA mask for the PMIC device,
which is also propagated to sub-devices.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml | 3 +++
drivers/mfd/sec-common.c | 3 +++
2 files changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml b/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
index d3d305b9aa765..849740868d728 100644
--- a/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
+++ b/Documentation/devicetree/bindings/mfd/samsung,s2mps11.yaml
@@ -356,6 +356,9 @@ examples:
};
port {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
muic_to_charger: endpoint@0 {
reg = <0>;
remote-endpoint = <&charger_to_muic>;
diff --git a/drivers/mfd/sec-common.c b/drivers/mfd/sec-common.c
index b3268516bf75e..883e6d0aa3f06 100644
--- a/drivers/mfd/sec-common.c
+++ b/drivers/mfd/sec-common.c
@@ -215,6 +215,9 @@ int sec_pmic_probe(struct device *dev, int device_type, unsigned int irq,
if (IS_ERR(irq_data))
return PTR_ERR(irq_data);
+ dev->coherent_dma_mask = 0;
+ dev->dma_mask = &dev->coherent_dma_mask;
+
pm_runtime_set_active(sec_pmic->dev);
switch (sec_pmic->device_type) {
--
2.53.0
^ permalink raw reply related
* [PATCH v4 08/13] mfd: sec: resolve PMIC revision in S2MU005
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
In devices other than S2MPG1X, the revision can be retrieved from the
first register of the PMIC regmap. In S2MU005 however, the location is
in offset 0x73. Introduce a switch-case block to allow selecting the
REG_ID register.
S2MU005 also has a field mask for the revision. Apply it using
FIELD_GET() and get the extracted value.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/mfd/sec-common.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/mfd/sec-common.c b/drivers/mfd/sec-common.c
index 883e6d0aa3f06..43215605191e4 100644
--- a/drivers/mfd/sec-common.c
+++ b/drivers/mfd/sec-common.c
@@ -16,6 +16,7 @@
#include <linux/mfd/samsung/irq.h>
#include <linux/mfd/samsung/s2mps11.h>
#include <linux/mfd/samsung/s2mps13.h>
+#include <linux/mfd/samsung/s2mu005.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm.h>
@@ -119,20 +120,27 @@ static const struct mfd_cell s2mu005_devs[] = {
static void sec_pmic_dump_rev(struct sec_pmic_dev *sec_pmic)
{
- unsigned int val;
+ unsigned int reg, mask, val;
- /* For s2mpg1x, the revision is in a different regmap */
switch (sec_pmic->device_type) {
case S2MPG10:
case S2MPG11:
+ /* For s2mpg1x, the revision is in a different regmap */
return;
- default:
+ case S2MU005:
+ reg = S2MU005_REG_ID;
+ mask = S2MU005_ID_MASK;
break;
+ default:
+ /* For other device types, REG_ID is always the first register. */
+ reg = S2MPS11_REG_ID;
+ mask = ~0;
}
- /* For each device type, the REG_ID is always the first register */
- if (!regmap_read(sec_pmic->regmap_pmic, S2MPS11_REG_ID, &val))
+ if (!regmap_read(sec_pmic->regmap_pmic, reg, &val)) {
+ val = FIELD_GET(S2MU005_ID_MASK, val);
dev_dbg(sec_pmic->dev, "Revision: 0x%x\n", val);
+ }
}
static void sec_pmic_configure(struct sec_pmic_dev *sec_pmic)
--
2.53.0
^ permalink raw reply related
* [PATCH v4 09/13] leds: flash: add support for Samsung S2M series PMIC flash LED device
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Add support for flash LEDs found in certain Samsung S2M series PMICs.
The device has two channels for LEDs, typically for the back and front
cameras in mobile devices. Both channels can be independently
controlled, and can be operated in torch or flash modes.
The driver includes initial support for the S2MU005 PMIC flash LEDs.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/leds/flash/Kconfig | 12 ++
drivers/leds/flash/Makefile | 1 +
drivers/leds/flash/leds-s2m-flash.c | 357 ++++++++++++++++++++++++++++++++++++
3 files changed, 370 insertions(+)
diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
index 5e08102a67841..be62e05277429 100644
--- a/drivers/leds/flash/Kconfig
+++ b/drivers/leds/flash/Kconfig
@@ -114,6 +114,18 @@ config LEDS_RT8515
To compile this driver as a module, choose M here: the module
will be called leds-rt8515.
+config LEDS_S2M_FLASH
+ tristate "Samsung S2M series PMICs flash/torch LED support"
+ depends on LEDS_CLASS
+ depends on MFD_SEC_CORE
+ depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+ select REGMAP_IRQ
+ help
+ This option enables support for the flash/torch LEDs found in
+ certain Samsung S2M series PMICs, such as the S2MU005. It has
+ a LED channel dedicated for every physical LED. The LEDs can
+ be controlled in flash and torch modes.
+
config LEDS_SGM3140
tristate "LED support for the SGM3140"
depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
index 712fb737a428e..44e6c1b4beb37 100644
--- a/drivers/leds/flash/Makefile
+++ b/drivers/leds/flash/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_LEDS_MAX77693) += leds-max77693.o
obj-$(CONFIG_LEDS_QCOM_FLASH) += leds-qcom-flash.o
obj-$(CONFIG_LEDS_RT4505) += leds-rt4505.o
obj-$(CONFIG_LEDS_RT8515) += leds-rt8515.o
+obj-$(CONFIG_LEDS_S2M_FLASH) += leds-s2m-flash.o
obj-$(CONFIG_LEDS_SGM3140) += leds-sgm3140.o
obj-$(CONFIG_LEDS_SY7802) += leds-sy7802.o
obj-$(CONFIG_LEDS_TPS6131X) += leds-tps6131x.o
diff --git a/drivers/leds/flash/leds-s2m-flash.c b/drivers/leds/flash/leds-s2m-flash.c
new file mode 100644
index 0000000000000..1ec592417c344
--- /dev/null
+++ b/drivers/leds/flash/leds-s2m-flash.c
@@ -0,0 +1,357 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Flash and Torch LED Driver for Samsung S2M series PMICs.
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd
+ * Copyright (c) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ */
+
+#include <linux/container_of.h>
+#include <linux/led-class-flash.h>
+#include <linux/mfd/samsung/core.h>
+#include <linux/mfd/samsung/s2mu005.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <media/v4l2-flash-led-class.h>
+
+#define MAX_CHANNELS 2
+
+struct s2m_led {
+ struct regmap *regmap;
+ struct led_classdev_flash fled;
+ struct v4l2_flash *v4l2_flash;
+ /*
+ * The mutex object prevents the concurrent access of flash control
+ * registers by the LED and V4L2 subsystems.
+ */
+ struct mutex lock;
+ unsigned int reg_enable;
+ u8 channel;
+ u8 flash_brightness;
+ u8 flash_timeout;
+};
+
+static struct s2m_led *to_s2m_led(struct led_classdev_flash *fled)
+{
+ return container_of(fled, struct s2m_led, fled);
+}
+
+static struct led_classdev_flash *to_s2m_fled(struct led_classdev *cdev)
+{
+ return container_of(cdev, struct led_classdev_flash, led_cdev);
+}
+
+static int s2m_fled_flash_brightness_set(struct led_classdev_flash *fled, u32 brightness)
+{
+ struct s2m_led *led = to_s2m_led(fled);
+ struct led_flash_setting *setting = &fled->brightness;
+
+ led->flash_brightness = (brightness - setting->min) / setting->step;
+
+ return 0;
+}
+
+static int s2m_fled_flash_timeout_set(struct led_classdev_flash *fled, u32 timeout)
+{
+ struct s2m_led *led = to_s2m_led(fled);
+ struct led_flash_setting *setting = &fled->timeout;
+
+ led->flash_timeout = (timeout - setting->min) / setting->step;
+
+ return 0;
+}
+
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+static int s2m_fled_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
+{
+ struct s2m_led *led = to_led(v4l2_flash->fled_cdev);
+
+ mutex_lock(&led->lock);
+
+ led->fled.ops->strobe_set(&led->fled, enable);
+
+ mutex_unlock(&led->lock);
+
+ return 0;
+}
+
+static const struct v4l2_flash_ops s2m_fled_v4l2_flash_ops = {
+ .external_strobe_set = s2m_fled_flash_external_strobe_set,
+};
+#else
+static const struct v4l2_flash_ops s2m_fled_v4l2_flash_ops;
+#endif
+
+static void s2m_fled_v4l2_flash_release(void *v4l2_flash)
+{
+ v4l2_flash_release(v4l2_flash);
+}
+
+static int s2mu005_fled_torch_brightness_set(struct led_classdev *cdev, enum led_brightness value)
+{
+ struct s2m_led *led = to_s2m_led(to_s2m_fled(cdev));
+ int ret;
+
+ mutex_lock(&led->lock);
+
+ if (!value) {
+ ret = regmap_clear_bits(led->regmap, led->reg_enable,
+ S2MU005_FLED_TORCH_EN(led->channel));
+ if (ret < 0)
+ dev_err(cdev->dev, "failed to disable torch LED\n");
+ goto unlock;
+ }
+
+ ret = regmap_update_bits(led->regmap, S2MU005_REG_FLED_CH_CTRL1(led->channel),
+ S2MU005_FLED_TORCH_IOUT,
+ FIELD_PREP(S2MU005_FLED_TORCH_IOUT, value - 1));
+ if (ret < 0) {
+ dev_err(cdev->dev, "failed to set torch current\n");
+ goto unlock;
+ }
+
+ ret = regmap_set_bits(led->regmap, led->reg_enable, S2MU005_FLED_TORCH_EN(led->channel));
+ if (ret < 0) {
+ dev_err(cdev->dev, "failed to enable torch LED\n");
+ goto unlock;
+ }
+
+unlock:
+ mutex_unlock(&led->lock);
+
+ return ret;
+}
+
+static int s2mu005_fled_flash_strobe_set(struct led_classdev_flash *fled, bool state)
+{
+ struct s2m_led *led = to_s2m_led(fled);
+ int ret;
+
+ mutex_lock(&led->lock);
+
+ ret = regmap_clear_bits(led->regmap, led->reg_enable, S2MU005_FLED_FLASH_EN(led->channel));
+ if (ret < 0) {
+ dev_err(fled->led_cdev.dev, "failed to disable flash LED\n");
+ goto unlock;
+ }
+
+ if (!state)
+ goto unlock;
+
+ ret = regmap_update_bits(led->regmap, S2MU005_REG_FLED_CH_CTRL0(led->channel),
+ S2MU005_FLED_FLASH_IOUT,
+ FIELD_PREP(S2MU005_FLED_FLASH_IOUT, led->flash_brightness));
+ if (ret < 0) {
+ dev_err(fled->led_cdev.dev, "failed to set flash brightness\n");
+ goto unlock;
+ }
+
+ ret = regmap_update_bits(led->regmap, S2MU005_REG_FLED_CH_CTRL3(led->channel),
+ S2MU005_FLED_FLASH_TIMEOUT,
+ FIELD_PREP(S2MU005_FLED_FLASH_TIMEOUT, led->flash_timeout));
+ if (ret < 0) {
+ dev_err(fled->led_cdev.dev, "failed to set flash timeout\n");
+ goto unlock;
+ }
+
+ ret = regmap_set_bits(led->regmap, led->reg_enable, S2MU005_FLED_FLASH_EN(led->channel));
+ if (ret < 0) {
+ dev_err(fled->led_cdev.dev, "failed to enable flash LED\n");
+ goto unlock;
+ }
+
+unlock:
+ mutex_unlock(&led->lock);
+
+ return 0;
+}
+
+static int s2mu005_fled_flash_strobe_get(struct led_classdev_flash *fled, bool *state)
+{
+ struct s2m_led *led = to_s2m_led(fled);
+ u32 val;
+ int ret;
+
+ mutex_lock(&led->lock);
+
+ ret = regmap_read(led->regmap, S2MU005_REG_FLED_STATUS, &val);
+ if (ret < 0) {
+ dev_err(fled->led_cdev.dev, "failed to fetch LED status");
+ goto unlock;
+ }
+
+ *state = !!(val & S2MU005_FLED_FLASH_STATUS(led->channel));
+
+unlock:
+ mutex_unlock(&led->lock);
+
+ return ret;
+}
+
+static const struct led_flash_ops s2mu005_fled_flash_ops = {
+ .flash_brightness_set = s2m_fled_flash_brightness_set,
+ .timeout_set = s2m_fled_flash_timeout_set,
+ .strobe_set = s2mu005_fled_flash_strobe_set,
+ .strobe_get = s2mu005_fled_flash_strobe_get,
+};
+
+static int s2mu005_fled_init(struct s2m_led *led, struct device *dev, struct regmap *regmap,
+ unsigned int nr_channels)
+{
+ unsigned int val;
+ int i, ret;
+
+ /* Enable the LED channels. */
+ ret = regmap_set_bits(regmap, S2MU005_REG_FLED_CTRL1, S2MU005_FLED_CH_EN);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to enable LED channels\n");
+
+ ret = regmap_read(regmap, S2MU005_REG_ID, &val);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to read revision\n");
+
+ for (i = 0; i < nr_channels; i++) {
+ /*
+ * Read the revision register. Revision EVT0 has the register
+ * at CTRL4, while EVT1 and higher have it at CTRL6.
+ */
+ if (FIELD_GET(S2MU005_ID_MASK, val) == 0)
+ led[i].reg_enable = S2MU005_REG_FLED_CTRL4;
+ else
+ led[i].reg_enable = S2MU005_REG_FLED_CTRL6;
+ }
+
+ return 0;
+}
+
+static int s2mu005_fled_init_channel(struct s2m_led *led, struct device *dev,
+ struct fwnode_handle *fwnp)
+{
+ struct led_classdev *cdev = &led->fled.led_cdev;
+ struct led_init_data init_data = {};
+ struct v4l2_flash_config v4l2_cfg = {};
+ int ret;
+ cdev->max_brightness = 16;
+ cdev->brightness_set_blocking = s2mu005_fled_torch_brightness_set,
+ cdev->flags |= LED_DEV_CAP_FLASH;
+
+ led->fled.timeout.min = 62000;
+ led->fled.timeout.step = 62000;
+ led->fled.timeout.max = 992000;
+ led->fled.timeout.val = 992000;
+
+ led->fled.brightness.min = 25000;
+ led->fled.brightness.step = 25000;
+ led->fled.brightness.max = 375000; /* 400000 causes flickering */
+ led->fled.brightness.val = 375000;
+
+ s2m_fled_flash_timeout_set(&led->fled, led->fled.timeout.val);
+ s2m_fled_flash_brightness_set(&led->fled, led->fled.brightness.val);
+
+ led->fled.ops = &s2mu005_fled_flash_ops;
+
+ init_data.fwnode = fwnp;
+ ret = devm_led_classdev_flash_register_ext(dev, &led->fled, &init_data);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to create LED flash device\n");
+
+ v4l2_cfg.intensity.min = led->fled.timeout.min;
+ v4l2_cfg.intensity.step = led->fled.timeout.step;
+ v4l2_cfg.intensity.max = led->fled.timeout.max;
+ v4l2_cfg.intensity.val = led->fled.timeout.val;
+
+ v4l2_cfg.has_external_strobe = true;
+
+ led->v4l2_flash = v4l2_flash_init(dev, fwnp, &led->fled, &s2m_fled_v4l2_flash_ops,
+ &v4l2_cfg);
+ if (IS_ERR(led->v4l2_flash)) {
+ v4l2_flash_release(led->v4l2_flash);
+ return dev_err_probe(dev, PTR_ERR(led->v4l2_flash),
+ "failed to create V4L2 flash device\n");
+ }
+
+ ret = devm_add_action_or_reset(dev, (void *)s2m_fled_v4l2_flash_release, led->v4l2_flash);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to add cleanup action\n");
+
+ return 0;
+}
+
+static int s2m_fled_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sec_pmic_dev *ddata = dev_get_drvdata(dev->parent);
+ struct s2m_led *led;
+ int ret;
+
+ led = devm_kzalloc(dev, sizeof(*led) * MAX_CHANNELS, GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ switch (platform_get_device_id(pdev)->driver_data) {
+ case S2MU005:
+ ret = s2mu005_fled_init(led, dev, ddata->regmap_pmic, MAX_CHANNELS);
+ if (ret)
+ return ret;
+ break;
+ default:
+ return dev_err_probe(dev, -ENODEV, "device type %d is not supported by driver\n",
+ ddata->device_type);
+ }
+
+ device_for_each_child_node_scoped(dev, child) {
+ u32 reg;
+
+ if (fwnode_property_read_u32(child, "reg", ®))
+ continue;
+
+ if (led[reg].regmap) {
+ dev_warn(dev, "duplicate node for channel %d\n", reg);
+ continue;
+ }
+
+ led[reg].regmap = ddata->regmap_pmic;
+ led[reg].channel = (u8)reg;
+
+ ret = devm_mutex_init(dev, &led[reg].lock);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to create mutex\n");
+
+ switch (platform_get_device_id(pdev)->driver_data) {
+ case S2MU005:
+ ret = s2mu005_fled_init_channel(led + reg, dev, child);
+ if (ret < 0)
+ return ret;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static const struct platform_device_id s2m_fled_id_table[] = {
+ { "s2mu005-flash", S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, s2m_fled_id_table);
+
+static const struct of_device_id s2m_fled_of_match_table[] = {
+ { .compatible = "samsung,s2mu005-flash", .data = (void *)S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, s2m_fled_of_match_table);
+
+static struct platform_driver s2m_fled_driver = {
+ .driver = {
+ .name = "s2m-flash",
+ },
+ .probe = s2m_fled_probe,
+ .id_table = s2m_fled_id_table,
+};
+module_platform_driver(s2m_fled_driver);
+
+MODULE_DESCRIPTION("Flash/Torch LED Driver For Samsung S2M Series PMICs");
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschluss@disroot.org>");
+MODULE_LICENSE("GPL");
--
2.53.0
^ permalink raw reply related
* [PATCH v4 10/13] leds: rgb: add support for Samsung S2M series PMIC RGB LED device
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Add support for the RGB LEDs found in certain Samsung S2M series PMICs.
The device has three LED channels, controlled as a single device. These
LEDs are typically used as status indicators in mobile phones.
The driver includes initial support for the S2MU005 PMIC RGB LEDs.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/leds/rgb/Kconfig | 11 +
drivers/leds/rgb/Makefile | 1 +
drivers/leds/rgb/leds-s2m-rgb.c | 446 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 458 insertions(+)
diff --git a/drivers/leds/rgb/Kconfig b/drivers/leds/rgb/Kconfig
index 28ef4c487367c..30051342f4e4d 100644
--- a/drivers/leds/rgb/Kconfig
+++ b/drivers/leds/rgb/Kconfig
@@ -75,6 +75,17 @@ config LEDS_QCOM_LPG
If compiled as a module, the module will be named leds-qcom-lpg.
+config LEDS_S2M_RGB
+ tristate "Samsung S2M series PMICs RGB LED support"
+ depends on LEDS_CLASS
+ depends on MFD_SEC_CORE
+ select REGMAP_IRQ
+ help
+ This option enables support for the S2MU005 RGB LEDs. These
+ devices have three LED channels, with 8-bit brightness control
+ for each channel. It's usually found in mobile phones as
+ status indicators.
+
config LEDS_MT6370_RGB
tristate "LED Support for MediaTek MT6370 PMIC"
depends on MFD_MT6370
diff --git a/drivers/leds/rgb/Makefile b/drivers/leds/rgb/Makefile
index be45991f63f50..98050e1aa4255 100644
--- a/drivers/leds/rgb/Makefile
+++ b/drivers/leds/rgb/Makefile
@@ -6,4 +6,5 @@ obj-$(CONFIG_LEDS_LP5812) += leds-lp5812.o
obj-$(CONFIG_LEDS_NCP5623) += leds-ncp5623.o
obj-$(CONFIG_LEDS_PWM_MULTICOLOR) += leds-pwm-multicolor.o
obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-lpg.o
+obj-$(CONFIG_LEDS_S2M_RGB) += leds-s2m-rgb.o
obj-$(CONFIG_LEDS_MT6370_RGB) += leds-mt6370-rgb.o
diff --git a/drivers/leds/rgb/leds-s2m-rgb.c b/drivers/leds/rgb/leds-s2m-rgb.c
new file mode 100644
index 0000000000000..5cefe8b990fb4
--- /dev/null
+++ b/drivers/leds/rgb/leds-s2m-rgb.c
@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RGB LED Driver for Samsung S2M series PMICs.
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd
+ * Copyright (c) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ */
+
+#include <linux/container_of.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/mfd/samsung/core.h>
+#include <linux/mfd/samsung/s2mu005.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+struct s2m_rgb {
+ struct device *dev;
+ struct regmap *regmap;
+ struct led_classdev_mc mc;
+ enum sec_device_type device_type;
+ /*
+ * The mutex object prevents race conditions when evaluation and
+ * application of LED pattern state.
+ */
+ struct mutex lock;
+ /*
+ * State variables representing the current LED pattern, these only to
+ * be accessed when lock is held.
+ */
+ u8 ramp_up;
+ u8 ramp_dn;
+ u8 stay_hi;
+ u8 stay_lo;
+};
+
+static struct led_classdev_mc *to_s2m_mc(struct led_classdev *cdev)
+{
+ return container_of(cdev, struct led_classdev_mc, led_cdev);
+}
+
+static struct s2m_rgb *to_s2m_rgb(struct led_classdev_mc *mc)
+{
+ return container_of(mc, struct s2m_rgb, mc);
+}
+
+static const u32 s2mu005_rgb_lut_ramp[] = {
+ 0, 100, 200, 300, 400, 500, 600, 700,
+ 800, 1000, 1200, 1400, 1600, 1800, 2000, 2200,
+};
+
+static const u32 s2mu005_rgb_lut_stay_hi[] = {
+ 100, 200, 300, 400, 500, 750, 1000, 1250,
+ 1500, 1750, 2000, 2250, 2500, 2750, 3000, 3250,
+};
+
+static const u32 s2mu005_rgb_lut_stay_lo[] = {
+ 0, 500, 1000, 1500, 2000, 2500, 3000, 3500,
+ 4000, 4500, 5000, 6000, 7000, 8000, 10000, 12000,
+};
+
+static int s2mu005_rgb_apply_params(struct s2m_rgb *rgb)
+{
+ struct regmap *regmap = rgb->regmap;
+ unsigned int ramp_val = 0;
+ unsigned int stay_val = 0;
+ int ret;
+ int i;
+
+ ramp_val |= FIELD_PREP(S2MU005_RGB_CH_RAMP_UP, rgb->ramp_up);
+ ramp_val |= FIELD_PREP(S2MU005_RGB_CH_RAMP_DN, rgb->ramp_dn);
+
+ stay_val |= FIELD_PREP(S2MU005_RGB_CH_STAY_HI, rgb->stay_hi);
+ stay_val |= FIELD_PREP(S2MU005_RGB_CH_STAY_LO, rgb->stay_lo);
+
+ ret = regmap_write(regmap, S2MU005_REG_RGB_EN, S2MU005_RGB_RESET);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to reset RGB LEDs\n");
+ return ret;
+ }
+
+ for (i = 0; i < rgb->mc.num_colors; i++) {
+ ret = regmap_write(regmap, S2MU005_REG_RGB_CH_CTRL(i),
+ rgb->mc.subled_info[i].brightness);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to set LED brightness\n");
+ return ret;
+ }
+
+ ret = regmap_write(regmap, S2MU005_REG_RGB_CH_RAMP(i), ramp_val);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to set ramp timings\n");
+ return ret;
+ }
+
+ ret = regmap_write(regmap, S2MU005_REG_RGB_CH_STAY(i), stay_val);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to set stay timings\n");
+ return ret;
+ }
+ }
+
+ ret = regmap_update_bits(regmap, S2MU005_REG_RGB_EN, S2MU005_RGB_SLOPE,
+ S2MU005_RGB_SLOPE_SMOOTH);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to set ramp slope\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int s2mu005_rgb_reset_params(struct s2m_rgb *rgb)
+{
+ struct regmap *regmap = rgb->regmap;
+ int ret;
+
+ ret = regmap_write(regmap, S2MU005_REG_RGB_EN, S2MU005_RGB_RESET);
+ if (ret < 0) {
+ dev_err(rgb->dev, "failed to reset RGB LEDs\n");
+ return ret;
+ }
+
+ rgb->ramp_up = 0;
+ rgb->ramp_dn = 0;
+ rgb->stay_hi = 0;
+ rgb->stay_lo = 0;
+
+ return 0;
+}
+
+static int s2m_rgb_lut_calc_timing(const u32 *lut, const size_t len,
+ const u32 req_time, u8 *idx)
+{
+ int lo = 0;
+ int hi = len - 2;
+
+ /* Bounds checking */
+ if (req_time < lut[0] || req_time > lut[len - 1])
+ return -EINVAL;
+
+ /*
+ * Perform a binary search to pick the best timing from the LUT.
+ *
+ * The search algorithm picks two consecutive elements of the
+ * LUT and tries to search the pair between which the requested
+ * time lies.
+ */
+ while (lo <= hi) {
+ *idx = (lo + hi) / 2;
+
+ if ((lut[*idx] <= req_time) && (req_time <= lut[*idx + 1]))
+ break;
+
+ if ((req_time < lut[*idx]) && (req_time < lut[*idx + 1]))
+ hi = *idx - 1;
+ else
+ lo = *idx + 1;
+ }
+
+ /*
+ * The searched timing is always less than the requested time. At
+ * times, the succeeding timing in the LUT is closer thus more
+ * accurate. Adjust the resulting value if that's the case.
+ */
+ if (abs(req_time - lut[*idx]) > abs(lut[*idx + 1] - req_time))
+ (*idx)++;
+
+ return 0;
+}
+
+static int s2m_rgb_pattern_set(struct led_classdev *cdev, struct led_pattern *pattern,
+ u32 len, int repeat)
+{
+ struct s2m_rgb *rgb = to_s2m_rgb(to_s2m_mc(cdev));
+ const u32 *lut_ramp_up, *lut_ramp_dn, *lut_stay_hi, *lut_stay_lo;
+ size_t lut_ramp_up_len, lut_ramp_dn_len, lut_stay_hi_len, lut_stay_lo_len;
+ int brightness_peak = 0;
+ u32 time_hi = 0, time_lo = 0;
+ bool ramp_up_en, ramp_dn_en;
+ int ret;
+ int i;
+
+ /*
+ * The typical pattern supported by this device can be
+ * represented with the following graph:
+ *
+ * 255 T ''''''-. .-'''''''-.
+ * | '. .' '.
+ * | \ / \
+ * | '. .' '.
+ * | '-...........-' '-
+ * 0 +----------------------------------------------------> time (s)
+ *
+ * <---- HIGH ----><-- LOW --><-------- HIGH --------->
+ * <-----><-------><---------><-------><-----><------->
+ * stay_hi ramp_dn stay_lo ramp_up stay_hi ramp_dn
+ *
+ * There are two states, named HIGH and LOW. HIGH has a non-zero
+ * brightness level, while LOW is of zero brightness. The
+ * pattern provided should mention only one zero and non-zero
+ * brightness level. The hardware always starts the pattern from
+ * the HIGH state, as shown in the graph.
+ *
+ * The HIGH state can be divided in three somewhat equal timings:
+ * ramp_up, stay_hi, and ramp_dn. The LOW state has only one
+ * timing: stay_lo.
+ */
+
+ /* Only indefinitely looping patterns are supported. */
+ if (repeat != -1)
+ return -EINVAL;
+
+ /* Pattern should consist of at least two tuples. */
+ if (len < 2)
+ return -EINVAL;
+
+ for (i = 0; i < len; i++) {
+ int brightness = pattern[i].brightness;
+ u32 delta_t = pattern[i].delta_t;
+
+ if (brightness) {
+ /*
+ * The pattern shold define only one non-zero
+ * brightness in the HIGH state. The device
+ * doesn't have any provisions to handle
+ * multiple peak brightness levels.
+ */
+ if (brightness_peak && brightness_peak != brightness)
+ return -EINVAL;
+
+ brightness_peak = brightness;
+ time_hi += delta_t;
+ ramp_dn_en = !!delta_t;
+ } else {
+ time_lo += delta_t;
+ ramp_up_en = !!delta_t;
+ }
+ }
+
+ switch (rgb->device_type) {
+ case S2MU005:
+ lut_ramp_up = s2mu005_rgb_lut_ramp;
+ lut_ramp_up_len = ARRAY_SIZE(s2mu005_rgb_lut_ramp);
+ lut_ramp_dn = s2mu005_rgb_lut_ramp;
+ lut_ramp_dn_len = ARRAY_SIZE(s2mu005_rgb_lut_ramp);
+ lut_stay_hi = s2mu005_rgb_lut_stay_hi;
+ lut_stay_hi_len = ARRAY_SIZE(s2mu005_rgb_lut_stay_hi);
+ lut_stay_lo = s2mu005_rgb_lut_stay_lo;
+ lut_stay_lo_len = ARRAY_SIZE(s2mu005_rgb_lut_stay_lo);
+ break;
+ default:
+ /* execution shouldn't reach here */
+ break;
+ }
+
+ mutex_lock(&rgb->lock);
+
+ /*
+ * The timings ramp_up, stay_hi, and ramp_dn of the HIGH state
+ * are roughly equal. Firstly, calculate and set timings for
+ * ramp_up and ramp_dn (making sure they're exactly equal).
+ */
+ rgb->ramp_up = 0;
+ rgb->ramp_dn = 0;
+
+ if (ramp_up_en) {
+ ret = s2m_rgb_lut_calc_timing(lut_ramp_up, lut_ramp_up_len, time_hi / 3,
+ &rgb->ramp_up);
+ if (ret < 0)
+ goto param_fail;
+ }
+
+ if (ramp_dn_en) {
+ ret = s2m_rgb_lut_calc_timing(lut_ramp_dn, lut_ramp_dn_len, time_hi / 3,
+ &rgb->ramp_dn);
+ if (ret < 0)
+ goto param_fail;
+ }
+
+ /*
+ * Subtract the allocated ramp timings from time_hi (and also
+ * making sure it doesn't underflow!). The remaining time is
+ * allocated to stay_hi.
+ */
+ time_hi -= min(time_hi, lut_ramp_up[rgb->ramp_up]);
+ time_hi -= min(time_hi, lut_ramp_dn[rgb->ramp_dn]);
+
+ ret = s2m_rgb_lut_calc_timing(lut_stay_hi, lut_stay_hi_len, time_hi, &rgb->stay_hi);
+ if (ret < 0)
+ goto param_fail;
+
+ ret = s2m_rgb_lut_calc_timing(lut_stay_lo, lut_stay_lo_len, time_lo, &rgb->stay_lo);
+ if (ret < 0)
+ goto param_fail;
+
+ led_mc_calc_color_components(&rgb->mc, brightness_peak);
+ switch (rgb->device_type) {
+ case S2MU005:
+ ret = s2mu005_rgb_apply_params(rgb);
+ break;
+ default:
+ /* execution shouldn't reach here */
+ break;
+ }
+ if (ret < 0)
+ goto param_fail;
+
+ mutex_unlock(&rgb->lock);
+
+ return 0;
+
+param_fail:
+ rgb->ramp_up = 0;
+ rgb->ramp_dn = 0;
+ rgb->stay_hi = 0;
+ rgb->stay_lo = 0;
+
+ mutex_unlock(&rgb->lock);
+
+ return ret;
+}
+
+static int s2m_rgb_pattern_clear(struct led_classdev *cdev)
+{
+ struct s2m_rgb *rgb = to_s2m_rgb(to_s2m_mc(cdev));
+ int ret = 0;
+
+ mutex_lock(&rgb->lock);
+
+ switch (rgb->device_type) {
+ case S2MU005:
+ ret = s2mu005_rgb_reset_params(rgb);
+ break;
+ default:
+ /* execution shouldn't reach here */
+ break;
+ }
+
+ mutex_unlock(&rgb->lock);
+
+ return ret;
+}
+
+static int s2m_rgb_brightness_set(struct led_classdev *cdev, enum led_brightness value)
+{
+ struct s2m_rgb *rgb = to_s2m_rgb(to_s2m_mc(cdev));
+ int ret = 0;
+
+ if (!value)
+ return s2m_rgb_pattern_clear(cdev);
+
+ mutex_lock(&rgb->lock);
+
+ led_mc_calc_color_components(&rgb->mc, value);
+ switch (rgb->device_type) {
+ case S2MU005:
+ ret = s2mu005_rgb_apply_params(rgb);
+ break;
+ default:
+ /* execution shouldn't reach here */
+ break;
+ }
+
+ mutex_unlock(&rgb->lock);
+
+ return ret;
+}
+
+static struct mc_subled s2mu005_rgb_subled_info[] = {
+ { .channel = 0, .color_index = LED_COLOR_ID_BLUE },
+ { .channel = 1, .color_index = LED_COLOR_ID_GREEN },
+ { .channel = 2, .color_index = LED_COLOR_ID_RED },
+};
+
+static int s2m_rgb_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sec_pmic_dev *pmic_drvdata = dev_get_drvdata(dev->parent);
+ struct s2m_rgb *rgb;
+ struct led_init_data init_data = {};
+ int ret;
+
+ rgb = devm_kzalloc(dev, sizeof(*rgb), GFP_KERNEL);
+ if (!rgb)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, rgb);
+ rgb->dev = dev;
+ rgb->regmap = pmic_drvdata->regmap_pmic;
+ rgb->device_type = platform_get_device_id(pdev)->driver_data;
+
+ switch (rgb->device_type) {
+ case S2MU005:
+ rgb->mc.subled_info = s2mu005_rgb_subled_info;
+ rgb->mc.num_colors = ARRAY_SIZE(s2mu005_rgb_subled_info);
+ break;
+ default:
+ return dev_err_probe(dev, -ENODEV, "device type %d is not supported by driver\n",
+ pmic_drvdata->device_type);
+ }
+
+ rgb->mc.led_cdev.max_brightness = 255;
+ rgb->mc.led_cdev.brightness_set_blocking = s2m_rgb_brightness_set;
+ rgb->mc.led_cdev.pattern_set = s2m_rgb_pattern_set;
+ rgb->mc.led_cdev.pattern_clear = s2m_rgb_pattern_clear;
+
+ ret = devm_mutex_init(dev, &rgb->lock);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to create mutex lock\n");
+
+ init_data.fwnode = of_fwnode_handle(dev->of_node);
+ ret = devm_led_classdev_multicolor_register_ext(dev, &rgb->mc, &init_data);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to create LED device\n");
+
+ return 0;
+}
+
+static const struct platform_device_id s2m_rgb_id_table[] = {
+ { "s2mu005-rgb", S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, s2m_rgb_id_table);
+
+static const struct of_device_id s2m_rgb_of_match_table[] = {
+ { .compatible = "samsung,s2mu005-rgb", .data = (void *)S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, s2m_rgb_of_match_table);
+
+static struct platform_driver s2m_rgb_driver = {
+ .driver = {
+ .name = "s2m-rgb",
+ },
+ .probe = s2m_rgb_probe,
+ .id_table = s2m_rgb_id_table,
+};
+module_platform_driver(s2m_rgb_driver);
+
+MODULE_DESCRIPTION("RGB LED Driver For Samsung S2M Series PMICs");
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschluss@disroot.org>");
+MODULE_LICENSE("GPL");
--
2.53.0
^ permalink raw reply related
* [PATCH v4 11/13] Documentation: leds: document pattern behavior of Samsung S2M series PMIC RGB LEDs
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Add documentation to describe how hardware patterns (as defined by the
documentation of led-class-multicolor) are parsed and implemented by the
Samsung S2M series PMIC RGB LED driver.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
Documentation/leds/index.rst | 1 +
Documentation/leds/leds-s2m-rgb.rst | 60 +++++++++++++++++++++++++++++++++++++
2 files changed, 61 insertions(+)
diff --git a/Documentation/leds/index.rst b/Documentation/leds/index.rst
index bebf440042787..23fa9ff7aaf4b 100644
--- a/Documentation/leds/index.rst
+++ b/Documentation/leds/index.rst
@@ -28,6 +28,7 @@ LEDs
leds-lp5812
leds-mlxcpld
leds-mt6370-rgb
+ leds-s2m-rgb
leds-sc27xx
leds-st1202
leds-qcom-lpg
diff --git a/Documentation/leds/leds-s2m-rgb.rst b/Documentation/leds/leds-s2m-rgb.rst
new file mode 100644
index 0000000000000..4f89a8c89ea86
--- /dev/null
+++ b/Documentation/leds/leds-s2m-rgb.rst
@@ -0,0 +1,60 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================================
+Samsung S2M Series PMIC RGB LED Driver
+======================================
+
+Description
+-----------
+
+The RGB LED on the S2M series PMIC hardware features a three-channel LED that
+is grouped together as a single device. Furthermore, it supports 8-bit
+brightness control for each channel. This LED is typically used as a status
+indicator in mobile devices. It also supports various parameters for hardware
+patterns.
+
+The hardware pattern can be programmed using the "pattern" trigger, using the
+hw_pattern attribute.
+
+/sys/class/leds/<led>/repeat
+----------------------------
+
+The hardware supports only indefinitely repeating patterns. The repeat
+attribute must be set to -1 for hardware patterns to function.
+
+/sys/class/leds/<led>/hw_pattern
+--------------------------------
+
+Specify a hardware pattern for the RGB LEDs.
+
+The pattern is a series of brightness levels and durations in milliseconds.
+There should be only one non-zero brightness level. Unlike the results
+described in leds-trigger-pattern, the transitions between on and off states
+are smoothed out by the hardware.
+
+Simple pattern::
+
+ "255 3000 0 1000"
+
+ 255 -+ ''''''-. .-'''''''-.
+ | '. .' '.
+ | \ / \
+ | '. .' '.
+ | '-.......-' '-
+ 0 -+-------+-------+-------+-------+-------+-------+--> time (s)
+ 0 1 2 3 4 5 6
+
+As described in leds-trigger-pattern, it is also possible to use zero-length
+entries to disable the ramping mechanism.
+
+On-Off pattern::
+
+ "255 1000 255 0 0 1000 0 0"
+
+ 255 -+ ------+ +-------+ +-------+
+ | | | | | |
+ | | | | | |
+ | | | | | |
+ | +-------+ +-------+ +-------
+ 0 -+-------+-------+-------+-------+-------+-------+--> time (s)
+ 0 1 2 3 4 5 6
--
2.53.0
^ permalink raw reply related
* [PATCH v4 12/13] extcon: add support for Samsung S2M series PMIC extcon devices
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Add a driver for MUIC devices found in certain Samsung S2M series PMICs
These are USB port accessory detectors. These devices report multiple
cable states depending on the ID-GND resistance measured by an internal
ADC.
The driver includes initial support for the S2MU005 PMIC extcon.
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/extcon/Kconfig | 10 ++
drivers/extcon/Makefile | 1 +
drivers/extcon/extcon-s2m.c | 354 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 365 insertions(+)
diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index 68d9df7d2dae0..19c712e591955 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -183,6 +183,16 @@ config EXTCON_RT8973A
and switch that is optimized to protect low voltage system
from abnormal high input voltage (up to 28V).
+config EXTCON_S2M
+ tristate "Samsung S2M series PMIC EXTCON support"
+ depends on MFD_SEC_CORE
+ select REGMAP_IRQ
+ help
+ This option enables support for MUIC devices found in certain
+ Samsung S2M series PMICs, such as the S2MU005. These devices
+ have internal ADCs measuring the ID-GND resistance, thereby
+ can be used as a USB port accessory detector.
+
config EXTCON_SM5502
tristate "Silicon Mitus SM5502/SM5504/SM5703 EXTCON support"
depends on I2C
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index 6482f2bfd6611..e3939786f3474 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_EXTCON_PALMAS) += extcon-palmas.o
obj-$(CONFIG_EXTCON_PTN5150) += extcon-ptn5150.o
obj-$(CONFIG_EXTCON_QCOM_SPMI_MISC) += extcon-qcom-spmi-misc.o
obj-$(CONFIG_EXTCON_RT8973A) += extcon-rt8973a.o
+obj-$(CONFIG_EXTCON_S2M) += extcon-s2m.o
obj-$(CONFIG_EXTCON_SM5502) += extcon-sm5502.o
obj-$(CONFIG_EXTCON_USB_GPIO) += extcon-usb-gpio.o
obj-$(CONFIG_EXTCON_USBC_CROS_EC) += extcon-usbc-cros-ec.o
diff --git a/drivers/extcon/extcon-s2m.c b/drivers/extcon/extcon-s2m.c
new file mode 100644
index 0000000000000..f57573f279755
--- /dev/null
+++ b/drivers/extcon/extcon-s2m.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Extcon Driver for Samsung S2M series PMICs.
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd
+ * Copyright (C) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ */
+
+#include <linux/delay.h>
+#include <linux/extcon-provider.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/samsung/core.h>
+#include <linux/mfd/samsung/s2mu005.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+struct s2m_muic {
+ struct device *dev;
+ struct regmap *regmap;
+ struct extcon_dev *extcon;
+ struct s2m_muic_irq_data *irq_data;
+ const unsigned int *extcon_cable;
+ bool attached;
+};
+
+struct s2m_muic_irq_data {
+ const char *name;
+ int (*const handler)(struct s2m_muic *);
+ int irq;
+};
+
+static int s2mu005_muic_detach(struct s2m_muic *priv)
+{
+ int ret;
+ int i;
+
+ ret = regmap_set_bits(priv->regmap, S2MU005_REG_MUIC_CTRL1,
+ S2MU005_MUIC_MAN_SW);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to disable manual switching\n");
+ return ret;
+ }
+
+ ret = regmap_set_bits(priv->regmap, S2MU005_REG_MUIC_CTRL3,
+ S2MU005_MUIC_ONESHOT_ADC);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to enable ADC oneshot mode\n");
+ return ret;
+ }
+
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_MUIC_SWCTRL, ~0);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to clear switch control register\n");
+ return ret;
+ }
+
+ /* Find all set states and clear them */
+ for (i = 0; priv->extcon_cable[i]; i++) {
+ unsigned int state = priv->extcon_cable[i];
+
+ if (extcon_get_state(priv->extcon, state) == true)
+ extcon_set_state_sync(priv->extcon, state, false);
+ }
+
+ priv->attached = false;
+
+ return 0;
+}
+
+static int s2mu005_muic_attach(struct s2m_muic *priv)
+{
+ unsigned int type;
+ int ret;
+
+ /* If any device is already attached, detach it */
+ if (priv->attached) {
+ s2mu005_muic_detach(priv);
+ msleep(100);
+ }
+
+ ret = regmap_read(priv->regmap, S2MU005_REG_MUIC_DEV1, &type);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read DEV1 register\n");
+ return ret;
+ }
+
+ /*
+ * All USB connections which require communication via its D+
+ * and D- wires need it.
+ */
+ if (type & (S2MU005_MUIC_OTG | S2MU005_MUIC_DCP | S2MU005_MUIC_SDP)) {
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_MUIC_SWCTRL,
+ S2MU005_MUIC_DM_DP,
+ FIELD_PREP(S2MU005_MUIC_DM_DP,
+ S2MU005_MUIC_DM_DP_USB));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to configure DM/DP pins\n");
+ return ret;
+ }
+ }
+
+ /*
+ * For OTG connections, enable manual switching and ADC oneshot
+ * mode. Since the port will now be supplying power, the
+ * internal ADC (measuring the ID-GND resistance) is made to
+ * poll periodically for any changes, so as to prevent any
+ * damages due to power.
+ */
+ if (type & S2MU005_MUIC_OTG) {
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_MUIC_CTRL1,
+ S2MU005_MUIC_MAN_SW);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to enable manual switching\n");
+ return ret;
+ }
+
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_MUIC_CTRL3,
+ S2MU005_MUIC_ONESHOT_ADC);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to disable ADC oneshot mode\n");
+ return ret;
+ }
+ }
+
+ switch (type) {
+ case S2MU005_MUIC_OTG:
+ dev_dbg(priv->dev, "USB OTG connection detected\n");
+ extcon_set_state_sync(priv->extcon, EXTCON_USB_HOST, true);
+ priv->attached = true;
+ break;
+ case S2MU005_MUIC_CDP:
+ dev_dbg(priv->dev, "USB CDP connection detected\n");
+ extcon_set_state_sync(priv->extcon, EXTCON_USB, true);
+ extcon_set_state_sync(priv->extcon, EXTCON_CHG_USB_CDP, true);
+ priv->attached = true;
+ break;
+ case S2MU005_MUIC_SDP:
+ dev_dbg(priv->dev, "USB SDP connection detected\n");
+ extcon_set_state_sync(priv->extcon, EXTCON_USB, true);
+ extcon_set_state_sync(priv->extcon, EXTCON_CHG_USB_SDP, true);
+ priv->attached = true;
+ break;
+ case S2MU005_MUIC_DCP:
+ dev_dbg(priv->dev, "USB DCP connection detected\n");
+ extcon_set_state_sync(priv->extcon, EXTCON_USB, true);
+ extcon_set_state_sync(priv->extcon, EXTCON_CHG_USB_DCP, true);
+ priv->attached = true;
+ break;
+ case S2MU005_MUIC_UART:
+ dev_dbg(priv->dev, "UART connection detected\n");
+ extcon_set_state_sync(priv->extcon, EXTCON_JIG, true);
+ priv->attached = true;
+ break;
+ }
+
+ if (!priv->attached)
+ dev_warn(priv->dev, "failed to recognize the device attached\n");
+
+ return ret;
+}
+
+static int s2mu005_muic_init(struct s2m_muic *priv)
+{
+ int ret = 0;
+
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_MUIC_LDOADC_L,
+ S2MU005_MUIC_VSET,
+ FIELD_PREP(S2MU005_MUIC_VSET,
+ S2MU005_MUIC_VSET_3P0V));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set internal ADC voltage regulator\n");
+ return ret;
+ }
+
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_MUIC_LDOADC_H,
+ S2MU005_MUIC_VSET,
+ FIELD_PREP(S2MU005_MUIC_VSET,
+ S2MU005_MUIC_VSET_3P0V));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set internal ADC voltage regulator\n");
+ return ret;
+ }
+
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_MUIC_CTRL1,
+ S2MU005_MUIC_IRQ);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to enable MUIC interrupts\n");
+ return ret;
+ }
+
+ return s2mu005_muic_attach(priv);
+}
+
+static const unsigned int s2mu005_muic_extcon_cable[] = {
+ EXTCON_USB,
+ EXTCON_USB_HOST,
+ EXTCON_CHG_USB_SDP,
+ EXTCON_CHG_USB_DCP,
+ EXTCON_CHG_USB_CDP,
+ EXTCON_JIG,
+ EXTCON_NONE,
+};
+
+static struct s2m_muic_irq_data s2mu005_muic_irq_data[] = {
+ {
+ .name = "attach",
+ .handler = s2mu005_muic_attach
+ }, {
+ .name = "detach",
+ .handler = s2mu005_muic_detach
+ }, {
+ /* sentinel */
+ }
+};
+
+static irqreturn_t s2m_muic_irq_func(int virq, void *data)
+{
+ struct s2m_muic *priv = data;
+ const struct s2m_muic_irq_data *irq_data = priv->irq_data;
+ int ret;
+ int i;
+
+ for (i = 0; irq_data[i].handler; i++) {
+ if (virq != irq_data[i].irq)
+ continue;
+
+ ret = irq_data[i].handler(priv);
+ if (ret < 0)
+ dev_err(priv->dev, "failed to handle interrupt for %s (%d)\n",
+ irq_data[i].name, ret);
+ break;
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int s2m_muic_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sec_pmic_dev *pmic_drvdata = dev_get_drvdata(dev->parent);
+ struct s2m_muic *priv;
+ int ret;
+ int i;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, priv);
+ priv->dev = dev;
+ priv->regmap = pmic_drvdata->regmap_pmic;
+
+ switch (platform_get_device_id(pdev)->driver_data) {
+ case S2MU005:
+ priv->extcon_cable = s2mu005_muic_extcon_cable;
+ priv->irq_data = s2mu005_muic_irq_data;
+ /* Initialize MUIC */
+ ret = s2mu005_muic_init(priv);
+ break;
+ default:
+ return dev_err_probe(dev, -ENODEV,
+ "device type %d is not supported by driver\n",
+ pmic_drvdata->device_type);
+ }
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to initialize MUIC\n");
+
+ priv->extcon = devm_extcon_dev_allocate(&pdev->dev, priv->extcon_cable);
+ if (IS_ERR(priv->extcon))
+ return dev_err_probe(dev, PTR_ERR(priv->extcon),
+ "failed to allocate memory for extcon\n");
+
+ ret = devm_extcon_dev_register(dev, priv->extcon);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to register extcon device\n");
+
+ for (i = 0; priv->irq_data[i].handler; i++) {
+ int irq = platform_get_irq_byname_optional(pdev,
+ priv->irq_data[i].name);
+ if (irq == -ENXIO)
+ continue;
+ if (irq <= 0)
+ return dev_err_probe(dev, -EINVAL, "failed to get IRQ %s\n",
+ priv->irq_data[i].name);
+
+ priv->irq_data[i].irq = irq;
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ s2m_muic_irq_func, IRQF_ONESHOT,
+ priv->irq_data[i].name, priv);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to request IRQ\n");
+ }
+
+ return 0;
+}
+
+static void s2m_muic_remove(struct platform_device *pdev)
+{
+ struct s2m_muic *priv = dev_get_drvdata(&pdev->dev);
+
+ /*
+ * Disabling the MUIC device is important as it disables manual
+ * switching mode, thereby enabling auto switching mode.
+ *
+ * This is to ensure that when the board is powered off, it
+ * goes into LPM charging mode when a USB charger is connected.
+ */
+ switch (platform_get_device_id(pdev)->driver_data) {
+ case S2MU005:
+ s2mu005_muic_detach(priv);
+ break;
+ }
+}
+
+static const struct platform_device_id s2m_muic_id_table[] = {
+ { "s2mu005-muic", S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, s2m_muic_id_table);
+
+/*
+ * Device is instantiated through parent MFD device and device matching
+ * is done through platform_device_id.
+ *
+ * However if device's DT node contains proper compatible and driver is
+ * built as a module, then the *module* matching will be done through DT
+ * aliases. This requires of_device_id table. In the same time this will
+ * not change the actual *device* matching so do not add .of_match_table.
+ */
+static const struct of_device_id s2m_muic_of_match_table[] = {
+ {
+ .compatible = "samsung,s2mu005-muic",
+ .data = (void *)S2MU005,
+ }, {
+ /* sentinel */
+ },
+};
+MODULE_DEVICE_TABLE(of, s2m_muic_of_match_table);
+
+static struct platform_driver s2m_muic_driver = {
+ .driver = {
+ .name = "s2m-muic",
+ },
+ .probe = s2m_muic_probe,
+ .remove = s2m_muic_remove,
+ .id_table = s2m_muic_id_table,
+};
+module_platform_driver(s2m_muic_driver);
+
+MODULE_DESCRIPTION("Extcon Driver For Samsung S2M Series PMICs");
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschluss@disroot.org>");
+MODULE_LICENSE("GPL");
--
2.53.0
^ permalink raw reply related
* [PATCH v4 13/13] power: supply: add support for Samsung S2M series PMIC charger device
From: Kaustabh Chakraborty @ 2026-04-14 6:33 UTC (permalink / raw)
To: Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, MyungJoo Ham, Chanwoo Choi, Sebastian Reichel,
Krzysztof Kozlowski, André Draszik, Alexandre Belloni,
Jonathan Corbet, Shuah Khan, Nam Tran,
Łukasz Lebiedziński
Cc: linux-leds, devicetree, linux-kernel, linux-pm, linux-samsung-soc,
linux-rtc, linux-doc, Kaustabh Chakraborty
In-Reply-To: <20260414-s2mu005-pmic-v4-0-7fe7480577e6@disroot.org>
Add a driver for charger controllers found in certain Samsung S2M series
PMICs. The driver has very basic support for the device, with only
charger online reporting working, and USB 2.0 device negotiations
working.
The driver includes initial support for the S2MU005 PMIC charger.
Co-developed-by: Łukasz Lebiedziński <kernel@lvkasz.us>
Signed-off-by: Łukasz Lebiedziński <kernel@lvkasz.us>
Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
---
drivers/power/supply/Kconfig | 11 ++
drivers/power/supply/Makefile | 1 +
drivers/power/supply/s2m-charger.c | 300 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/samsung/s2mu005.h | 5 +
4 files changed, 317 insertions(+)
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 83392ed6a8da9..6270e6d16fbbb 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -856,6 +856,17 @@ config CHARGER_RK817
help
Say Y to include support for Rockchip RK817 Battery Charger.
+config CHARGER_S2M
+ tristate "Samsung S2M series PMIC battery charger support"
+ depends on EXTCON_S2M
+ depends on MFD_SEC_CORE
+ select REGMAP_IRQ
+ help
+ This option enables support for charger devices found in
+ certain Samsung S2M series PMICs, such as the S2MU005. These
+ devices provide USB power supply information and also required
+ for USB OTG role switching.
+
config CHARGER_SMB347
tristate "Summit Microelectronics SMB3XX Battery Charger"
depends on I2C
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 7ee839dca7f33..738814650ea0f 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_CHARGER_BQ25890) += bq25890_charger.o
obj-$(CONFIG_CHARGER_BQ25980) += bq25980_charger.o
obj-$(CONFIG_CHARGER_BQ256XX) += bq256xx_charger.o
obj-$(CONFIG_CHARGER_RK817) += rk817_charger.o
+obj-$(CONFIG_CHARGER_S2M) += s2m-charger.o
obj-$(CONFIG_CHARGER_SMB347) += smb347-charger.o
obj-$(CONFIG_CHARGER_TPS65090) += tps65090-charger.o
obj-$(CONFIG_CHARGER_TPS65217) += tps65217_charger.o
diff --git a/drivers/power/supply/s2m-charger.c b/drivers/power/supply/s2m-charger.c
new file mode 100644
index 0000000000000..8836943f14faa
--- /dev/null
+++ b/drivers/power/supply/s2m-charger.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Battery Charger Driver for Samsung S2M series PMICs.
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd
+ * Copyright (c) 2026 Kaustabh Chakraborty <kauschluss@disroot.org>
+ * Copyright (c) 2026 Łukasz Lebiedziński <kernel@lvkasz.us>
+ */
+
+#include <linux/devm-helpers.h>
+#include <linux/extcon.h>
+#include <linux/mfd/samsung/core.h>
+#include <linux/mfd/samsung/s2mu005.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+struct s2m_chgr {
+ struct device *dev;
+ struct regmap *regmap;
+ struct power_supply *psy;
+ struct extcon_dev *extcon;
+ struct work_struct extcon_work;
+ struct notifier_block extcon_nb;
+};
+
+static int s2mu005_chgr_get_online(struct s2m_chgr *priv, int *value)
+{
+ u32 val;
+ int ret = 0;
+
+ ret = regmap_read(priv->regmap, S2MU005_REG_CHGR_STATUS0, &val);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to read register (%d)\n", ret);
+ return ret;
+ }
+
+ *value = !!(val & S2MU005_CHGR_CHG);
+
+ return ret;
+}
+
+static int s2mu005_chgr_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct s2m_chgr *priv = power_supply_get_drvdata(psy);
+ int ret = 0;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ ret = s2mu005_chgr_get_online(priv, &val->intval);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+static int s2mu005_chgr_mode_set_host(struct s2m_chgr *priv)
+{
+ int ret;
+
+ /* set mode to OTG */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL0,
+ S2MU005_CHGR_OP_MODE,
+ FIELD_PREP(S2MU005_CHGR_OP_MODE,
+ S2MU005_CHGR_OP_MODE_OTG));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set OTG mode (%d)\n", ret);
+ return ret;
+ }
+
+ /* set boost frequency to 2MHz */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL11,
+ S2MU005_CHGR_OSC_BOOST,
+ FIELD_PREP(S2MU005_CHGR_OSC_BOOST,
+ S2MU005_CHGR_OSC_BOOST_2MHZ));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set boost frequency (%d)\n", ret);
+ return ret;
+ }
+
+ /* set OTG current limit to 1.5 A */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL4,
+ S2MU005_CHGR_OTG_OCP,
+ FIELD_PREP(S2MU005_CHGR_OTG_OCP,
+ S2MU005_CHGR_OTG_OCP_1P5A));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set OTG current limit (%d)\n", ret);
+ return ret;
+ }
+
+ /* VBUS switches are OFF when OTG over-current happens */
+ ret = regmap_set_bits(priv->regmap, S2MU005_REG_CHGR_CTRL4,
+ S2MU005_CHGR_OTG_OCP_OFF);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set OTG OCP switch (%d)\n", ret);
+ return ret;
+ }
+
+ /* set OTG voltage to 5.1 V */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL5,
+ S2MU005_CHGR_VMID_BOOST,
+ FIELD_PREP(S2MU005_CHGR_VMID_BOOST,
+ S2MU005_CHGR_VMID_BOOST_5P1V));
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to set OTG voltage (%d)\n", ret);
+ return ret;
+ }
+
+ /* turn on OTG */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL15,
+ S2MU005_CHGR_OTG_EN,
+ FIELD_PREP(S2MU005_CHGR_OTG_EN,
+ S2MU005_CHGR_OTG_EN_ON));
+ if (ret < 0)
+ dev_err(priv->dev, "failed to turn on OTG (%d)\n", ret);
+ return ret;
+}
+
+static int s2mu005_chgr_mode_set_charger(struct s2m_chgr *priv)
+{
+ int ret;
+
+ /* first reset to mode 0 */
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_CHGR_CTRL0,
+ S2MU005_CHGR_OP_MODE);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to reset opmode (%d)\n", ret);
+ return ret;
+ }
+
+ /* wait for the charger to settle before switching to charging mode */
+ msleep(50);
+ /* then set to charging mode */
+ ret = regmap_update_bits(priv->regmap, S2MU005_REG_CHGR_CTRL0,
+ S2MU005_CHGR_OP_MODE,
+ FIELD_PREP(S2MU005_CHGR_OP_MODE,
+ S2MU005_CHGR_OP_MODE_CHG));
+ if (ret < 0)
+ dev_err(priv->dev, "failed to set opmode to charging (%d)\n", ret);
+ return ret;
+}
+
+static int s2mu005_chgr_mode_unset(struct s2m_chgr *priv)
+{
+ int ret;
+
+ /* turn off OTG */
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_CHGR_CTRL15,
+ S2MU005_CHGR_OTG_EN);
+ if (ret < 0) {
+ dev_err(priv->dev, "failed to turn off OTG (%d)\n", ret);
+ return ret;
+ }
+
+ /* reset operation mode */
+ ret = regmap_clear_bits(priv->regmap, S2MU005_REG_CHGR_CTRL0,
+ S2MU005_CHGR_OP_MODE);
+ if (ret < 0)
+ dev_err(priv->dev, "failed to reset opmode (%d)\n", ret);
+ return ret;
+}
+
+static void s2mu005_chgr_extcon_work(struct work_struct *work)
+{
+ struct s2m_chgr *priv = container_of(work, struct s2m_chgr,
+ extcon_work);
+
+ if (extcon_get_state(priv->extcon, EXTCON_USB_HOST))
+ s2mu005_chgr_mode_set_host(priv);
+ else if (extcon_get_state(priv->extcon, EXTCON_USB))
+ s2mu005_chgr_mode_set_charger(priv);
+ else
+ s2mu005_chgr_mode_unset(priv);
+
+ power_supply_changed(priv->psy);
+}
+
+static const enum power_supply_property s2mu005_chgr_properties[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+};
+
+static const struct power_supply_desc s2mu005_chgr_psy_desc = {
+ .name = "s2mu005-charger",
+ .type = POWER_SUPPLY_TYPE_USB,
+ .properties = s2mu005_chgr_properties,
+ .num_properties = ARRAY_SIZE(s2mu005_chgr_properties),
+ .get_property = s2mu005_chgr_get_property,
+};
+
+static int s2m_chgr_extcon_notifier(struct notifier_block *nb,
+ unsigned long event, void *param)
+{
+ struct s2m_chgr *priv = container_of(nb, struct s2m_chgr, extcon_nb);
+
+ schedule_work(&priv->extcon_work);
+
+ return NOTIFY_OK;
+}
+
+static int s2m_chgr_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sec_pmic_dev *pmic_drvdata = dev_get_drvdata(dev->parent);
+ struct s2m_chgr *priv;
+ struct device_node *extcon_node __free(device_node) = NULL;
+ struct power_supply_config psy_cfg = {};
+ const struct power_supply_desc *psy_desc;
+ work_func_t extcon_work_func;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, priv);
+ priv->dev = dev;
+ priv->regmap = pmic_drvdata->regmap_pmic;
+
+ switch (platform_get_device_id(pdev)->driver_data) {
+ case S2MU005:
+ psy_desc = &s2mu005_chgr_psy_desc;
+ extcon_work_func = s2mu005_chgr_extcon_work;
+ break;
+ default:
+ return dev_err_probe(dev, -ENODEV,
+ "device type %d is not supported by driver\n",
+ pmic_drvdata->device_type);
+ }
+
+ psy_cfg.drv_data = priv;
+ priv->psy = devm_power_supply_register(dev, psy_desc, &psy_cfg);
+ if (IS_ERR(priv->psy))
+ return dev_err_probe(dev, PTR_ERR(priv->psy),
+ "failed to register power supply subsystem\n");
+
+ /* MUIC is mandatory. If unavailable, request probe deferral */
+ if (!of_graph_is_present(dev->of_node))
+ return -ENODEV;
+ extcon_node = of_graph_get_remote_node(dev->of_node, 0, 0);
+ priv->extcon = extcon_find_edev_by_node(extcon_node);
+ if (IS_ERR(priv->extcon))
+ return -EPROBE_DEFER;
+
+ ret = devm_work_autocancel(dev, &priv->extcon_work, extcon_work_func);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to initialize extcon work\n");
+
+ priv->extcon_nb.notifier_call = s2m_chgr_extcon_notifier;
+ ret = devm_extcon_register_notifier_all(dev, priv->extcon, &priv->extcon_nb);
+ if (ret)
+ dev_err_probe(dev, ret, "failed to register extcon notifier\n");
+
+ return 0;
+}
+
+static const struct platform_device_id s2m_chgr_id_table[] = {
+ { "s2mu005-charger", S2MU005 },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, s2m_chgr_id_table);
+
+/*
+ * Device is instantiated through parent MFD device and device matching
+ * is done through platform_device_id.
+ *
+ * However if device's DT node contains proper compatible and driver is
+ * built as a module, then the *module* matching will be done through DT
+ * aliases. This requires of_device_id table. In the same time this will
+ * not change the actual *device* matching so do not add .of_match_table.
+ */
+static const struct of_device_id s2m_chgr_of_match_table[] = {
+ {
+ .compatible = "samsung,s2mu005-charger",
+ .data = (void *)S2MU005,
+ }, {
+ /* sentinel */
+ },
+};
+MODULE_DEVICE_TABLE(of, s2m_chgr_of_match_table);
+
+static struct platform_driver s2m_chgr_driver = {
+ .driver = {
+ .name = "s2m-charger",
+ },
+ .probe = s2m_chgr_probe,
+ .id_table = s2m_chgr_id_table,
+};
+module_platform_driver(s2m_chgr_driver);
+
+MODULE_DESCRIPTION("Battery Charger Driver For Samsung S2M Series PMICs");
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschluss@disroot.org>");
+MODULE_AUTHOR("Łukasz Lebiedziński <kernel@lvkasz.us>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/samsung/s2mu005.h b/include/linux/mfd/samsung/s2mu005.h
index 07f4ae664950d..00b5450cf1c60 100644
--- a/include/linux/mfd/samsung/s2mu005.h
+++ b/include/linux/mfd/samsung/s2mu005.h
@@ -2,6 +2,7 @@
/*
* Copyright (c) 2015 Samsung Electronics Co., Ltd
* Copyright (c) 2025 Kaustabh Chakraborty <kauschluss@disroot.org>
+ * Copyright (c) 2026 Łukasz Lebiedziński <kernel@lvkasz.us>
*/
#ifndef __LINUX_MFD_S2MU005_H
@@ -186,9 +187,11 @@ enum s2mu005_reg {
#define S2MU005_CHGR_OTG_OCP_ON BIT(5)
#define S2MU005_CHGR_OTG_OCP_OFF BIT(4)
#define S2MU005_CHGR_OTG_OCP GENMASK(3, 2)
+#define S2MU005_CHGR_OTG_OCP_1P5A 0x3
/* S2MU005_REG_CHGR_CTRL5 */
#define S2MU005_CHGR_VMID_BOOST GENMASK(4, 0)
+#define S2MU005_CHGR_VMID_BOOST_5P1V 0x16
/* S2MU005_REG_CHGR_CTRL6 */
#define S2MU005_CHGR_COOL_CHG_CURR GENMASK(5, 0)
@@ -205,6 +208,7 @@ enum s2mu005_reg {
/* S2MU005_REG_CHGR_CTRL11 */
#define S2MU005_CHGR_OSC_BOOST GENMASK(6, 5)
#define S2MU005_CHGR_OSC_BUCK GENMASK(4, 3)
+#define S2MU005_CHGR_OSC_BOOST_2MHZ 0x3
/* S2MU005_REG_CHGR_CTRL12 */
#define S2MU005_CHGR_WDT GENMASK(2, 0)
@@ -214,6 +218,7 @@ enum s2mu005_reg {
/* S2MU005_REG_CHGR_CTRL15 */
#define S2MU005_CHGR_OTG_EN GENMASK(3, 2)
+#define S2MU005_CHGR_OTG_EN_ON 0x3
/* S2MU005_REG_FLED_STATUS */
#define S2MU005_FLED_FLASH_STATUS(x) (BIT(7) >> 2 * (x))
--
2.53.0
^ permalink raw reply related
* [PATCH v10 00/12] VMSCAPE optimization for BHI variant
From: Pawan Gupta @ 2026-04-14 7:05 UTC (permalink / raw)
To: x86, Jon Kohler, Nikolay Borisov, H. Peter Anvin, Josh Poimboeuf,
David Kaplan, Sean Christopherson, Borislav Petkov, Dave Hansen,
Peter Zijlstra, Alexei Starovoitov, Daniel Borkmann,
Andrii Nakryiko, KP Singh, Jiri Olsa, David S. Miller,
David Laight, Andy Lutomirski, Thomas Gleixner, Ingo Molnar,
David Ahern, Martin KaFai Lau, Eduard Zingerman, Song Liu,
Yonghong Song, John Fastabend, Stanislav Fomichev, Hao Luo,
Paolo Bonzini, Jonathan Corbet
Cc: linux-kernel, kvm, Asit Mallick, Tao Zhang, bpf, netdev,
linux-doc
v10:
- Add patches to define EXPORT_STATIC_CALL_FOR_MODULES() and
EXPORT_STATIC_CALL_FOR_KVM(), so that vmscape_predictor_flush static key
is only accessible to KVM and not to other kernel modules. (PeterZ)
(Borisov earlier objected to exporting the static key to all modules, but
now the static key is only exported to KVM. I guess that resolves the
concern.)
- Avoid an explicit call to vmscape_mitigation_enabled() and instead use
static_call_query() in VMexit hot path. (Sean)
- Drop vmscape_mitigation_enabled(), as it is no longer needed.
- Rebased to v7.0
v9: https://lore.kernel.org/r/20260402-vmscape-bhb-v9-0-94d16bc29774@linux.intel.com
- Use global variables for BHB loop counters instead of ALTERNATIVE-based
approach. (Dave & others)
- Use 32-bit registers (%eax/%ecx) for loop counters, loaded via movzbl
from 8-bit globals. 8-bit registers (e.g. %ah in the inner loop) caused
performance regression on certain CPUs due to partial-register stalls. (David Laight)
- Let BPF save/restore %rax/%rcx as in the original implementation, since
it is the only caller that needs these registers preserved across the
BHB clearing sequence.
- Drop Reviewed-by from patch 2/10 as the implementation changed significantly.
- Apply Tested-by from Jon Kohler to the series (except patch 2/10).
- Fix commit message grammar. (Borislav)
- Rebased to v7.0-rc6.
v8: https://lore.kernel.org/r/20260324-vmscape-bhb-v8-0-68bb524b3ab9@linux.intel.com
- Use helper in KVM to convey the mitigation status. (PeterZ/Borisov)
- Fix the documentation for default vmscape mitigation. (BPF bot)
- Remove the stray lines in bug.c (BPF bot).
- Updated commit messages and comments.
- Rebased to v7.0-rc5.
v7: https://lore.kernel.org/r/20260319-vmscape-bhb-v7-0-b76a777a98af@linux.intel.com
- s/This allows/Allow/ and s/This does adds/This adds/ in patch 1/10 commit
message (Borislav).
- Minimize register usage in BHB clearing seq. (David Laight)
- Instead of separate ecx/eax counters, use al/ah.
- Adjust the alignment of RET due to register size change.
- save/restore rax in the seq itself.
- Remove the save/restore of rax/rcx for BPF callers.
- Rename clear_bhb_loop() to clear_bhb_loop_nofence() to make it
obvious that the LFENCE is not part of the sequence (Borislav).
- Fix Kconfig: s/select/depends on/ HAVE_STATIC_CALL (PeterZ).
- Rebased to v7.0-rc4.
v6: https://lore.kernel.org/r/20251201-vmscape-bhb-v6-0-d610dd515714@linux.intel.com
- Remove semicolon at the end of asm in ALTERNATIVE (Uros).
- Fix build warning in vmscape_select_mitigation() (LKP).
- Rebased to v6.18.
v5: https://lore.kernel.org/r/20251126-vmscape-bhb-v5-2-02d66e423b00@linux.intel.com
- For BHI seq, limit runtime-patching to loop counts only (Dave).
Dropped 2 patches that moved the BHB seq to a macro.
- Remove redundant switch cases in vmscape_select_mitigation() (Nikolay).
- Improve commit message (Nikolay).
- Collected tags.
v4: https://lore.kernel.org/r/20251119-vmscape-bhb-v4-0-1adad4e69ddc@linux.intel.com
- Move LFENCE to the callsite, out of clear_bhb_loop(). (Dave)
- Make clear_bhb_loop() work for larger BHB. (Dave)
This now uses hardware enumeration to determine the BHB size to clear.
- Use write_ibpb() instead of indirect_branch_prediction_barrier() when
IBPB is known to be available. (Dave)
- Use static_call() to simplify mitigation at exit-to-userspace. (Dave)
- Refactor vmscape_select_mitigation(). (Dave)
- Fix vmscape=on which was wrongly behaving as AUTO. (Dave)
- Split the patches. (Dave)
- Patch 1-4 prepares for making the sequence flexible for VMSCAPE use.
- Patch 5 trivial rename of variable.
- Patch 6-8 prepares for deploying BHB mitigation for VMSCAPE.
- Patch 9 deploys the mitigation.
- Patch 10-11 fixes ON Vs AUTO mode.
v3: https://lore.kernel.org/r/20251027-vmscape-bhb-v3-0-5793c2534e93@linux.intel.com
- s/x86_pred_flush_pending/x86_predictor_flush_exit_to_user/ (Sean).
- Removed IBPB & BHB-clear mutual exclusion at exit-to-userspace.
- Collected tags.
v2: https://lore.kernel.org/r/20251015-vmscape-bhb-v2-0-91cbdd9c3a96@linux.intel.com
- Added check for IBPB feature in vmscape_select_mitigation(). (David)
- s/vmscape=auto/vmscape=on/ (David)
- Added patch to remove LFENCE from VMSCAPE BHB-clear sequence.
- Rebased to v6.18-rc1.
v1: https://lore.kernel.org/r/20250924-vmscape-bhb-v1-0-da51f0e1934d@linux.intel.com
Hi All,
These patches aim to improve the performance of a recent mitigation for
VMSCAPE[1] vulnerability. This improvement is relevant for BHI variant of
VMSCAPE that affect Alder Lake and newer processors.
The current mitigation approach uses IBPB on kvm-exit-to-userspace for all
affected range of CPUs. This is an overkill for CPUs that are only affected
by the BHI variant. On such CPUs clearing the branch history is sufficient
for VMSCAPE, and also more apt as the underlying issue is due to poisoned
branch history.
Below is the iPerf data for transfer between guest and host, comparing IBPB
and BHB-clear mitigation. BHB-clear shows performance improvement over IBPB
in most cases.
Platform: Emerald Rapids
Baseline: vmscape=off
Target: IBPB at VMexit-to-userspace Vs the new BHB-clear at
VMexit-to-userspace mitigation (both compared against baseline).
(pN = N parallel connections)
| iPerf user-net | IBPB | BHB Clear |
|----------------|---------|-----------|
| UDP 1-vCPU_p1 | -12.5% | 1.3% |
| TCP 1-vCPU_p1 | -10.4% | -1.5% |
| TCP 1-vCPU_p1 | -7.5% | -3.0% |
| UDP 4-vCPU_p16 | -3.7% | -3.7% |
| TCP 4-vCPU_p4 | -2.9% | -1.4% |
| UDP 4-vCPU_p4 | -0.6% | 0.0% |
| TCP 4-vCPU_p4 | 3.5% | 0.0% |
| iPerf bridge-net | IBPB | BHB Clear |
|------------------|---------|-----------|
| UDP 1-vCPU_p1 | -9.4% | -0.4% |
| TCP 1-vCPU_p1 | -3.9% | -0.5% |
| UDP 4-vCPU_p16 | -2.2% | -3.8% |
| TCP 4-vCPU_p4 | -1.0% | -1.0% |
| TCP 4-vCPU_p4 | 0.5% | 0.5% |
| UDP 4-vCPU_p4 | 0.0% | 0.9% |
| TCP 1-vCPU_p1 | 0.0% | 0.9% |
| iPerf vhost-net | IBPB | BHB Clear |
|-----------------|---------|-----------|
| UDP 1-vCPU_p1 | -4.3% | 1.0% |
| TCP 1-vCPU_p1 | -3.8% | -0.5% |
| TCP 1-vCPU_p1 | -2.7% | -0.7% |
| UDP 4-vCPU_p16 | -0.7% | -2.2% |
| TCP 4-vCPU_p4 | -0.4% | 0.8% |
| UDP 4-vCPU_p4 | 0.4% | -0.7% |
| TCP 4-vCPU_p4 | 0.0% | 0.6% |
[1] https://comsec.ethz.ch/research/microarch/vmscape-exposing-and-exploiting-incomplete-branch-predictor-isolation-in-cloud-environments/
---
Pawan Gupta (12):
x86/bhi: x86/vmscape: Move LFENCE out of clear_bhb_loop()
x86/bhi: Make clear_bhb_loop() effective on newer CPUs
x86/bhi: Rename clear_bhb_loop() to clear_bhb_loop_nofence()
x86/vmscape: Rename x86_ibpb_exit_to_user to x86_predictor_flush_exit_to_user
x86/vmscape: Move mitigation selection to a switch()
x86/vmscape: Use write_ibpb() instead of indirect_branch_prediction_barrier()
static_call: Add EXPORT_STATIC_CALL_FOR_MODULES()
kvm: Define EXPORT_STATIC_CALL_FOR_KVM()
x86/vmscape: Use static_call() for predictor flush
x86/vmscape: Deploy BHB clearing mitigation
x86/vmscape: Resolve conflict between attack-vectors and vmscape=force
x86/vmscape: Add cmdline vmscape=on to override attack vector controls
Documentation/admin-guide/hw-vuln/vmscape.rst | 15 ++++-
Documentation/admin-guide/kernel-parameters.txt | 6 +-
arch/x86/Kconfig | 1 +
arch/x86/entry/entry_64.S | 21 ++++---
arch/x86/include/asm/cpufeatures.h | 2 +-
arch/x86/include/asm/entry-common.h | 13 ++--
arch/x86/include/asm/kvm_types.h | 1 +
arch/x86/include/asm/nospec-branch.h | 15 +++--
arch/x86/kernel/cpu/bugs.c | 84 +++++++++++++++++++++----
arch/x86/kvm/x86.c | 4 +-
arch/x86/net/bpf_jit_comp.c | 4 +-
include/linux/kvm_types.h | 13 +++-
include/linux/static_call.h | 8 +++
13 files changed, 150 insertions(+), 37 deletions(-)
---
base-commit: 028ef9c96e96197026887c0f092424679298aae8
change-id: 20250916-vmscape-bhb-d7d469977f2f
Best regards,
--
Thanks,
Pawan
^ permalink raw reply
* [PATCH v10 01/12] x86/bhi: x86/vmscape: Move LFENCE out of clear_bhb_loop()
From: Pawan Gupta @ 2026-04-14 7:05 UTC (permalink / raw)
To: x86, Jon Kohler, Nikolay Borisov, H. Peter Anvin, Josh Poimboeuf,
David Kaplan, Sean Christopherson, Borislav Petkov, Dave Hansen,
Peter Zijlstra, Alexei Starovoitov, Daniel Borkmann,
Andrii Nakryiko, KP Singh, Jiri Olsa, David S. Miller,
David Laight, Andy Lutomirski, Thomas Gleixner, Ingo Molnar,
David Ahern, Martin KaFai Lau, Eduard Zingerman, Song Liu,
Yonghong Song, John Fastabend, Stanislav Fomichev, Hao Luo,
Paolo Bonzini, Jonathan Corbet
Cc: linux-kernel, kvm, Asit Mallick, Tao Zhang, bpf, netdev,
linux-doc
In-Reply-To: <20260414-vmscape-bhb-v10-0-efa924abae5f@linux.intel.com>
Currently, the BHB clearing sequence is followed by an LFENCE to prevent
transient execution of subsequent indirect branches prematurely. However,
the LFENCE barrier could be unnecessary in certain cases. For example, when
the kernel is using the BHI_DIS_S mitigation, and BHB clearing is only
needed for userspace. In such cases, the LFENCE is redundant because ring
transitions would provide the necessary serialization.
Below is a quick recap of BHI mitigation options:
On Alder Lake and newer
BHI_DIS_S: Hardware control to mitigate BHI in ring0. This has low
performance overhead.
Long loop: Alternatively, a longer version of the BHB clearing sequence
can be used to mitigate BHI. It can also be used to mitigate the BHI
variant of VMSCAPE. This is not yet implemented in Linux.
On older CPUs
Short loop: Clears BHB at kernel entry and VMexit. The "Long loop" is
effective on older CPUs as well, but should be avoided because of
unnecessary overhead.
On Alder Lake and newer CPUs, eIBRS isolates the indirect targets between
guest and host. But when affected by the BHI variant of VMSCAPE, a guest's
branch history may still influence indirect branches in userspace. This
also means the big hammer IBPB could be replaced with a cheaper option that
clears the BHB at exit-to-userspace after a VMexit.
In preparation for adding the support for the BHB sequence (without LFENCE)
on newer CPUs, move the LFENCE to the caller side after clear_bhb_loop() is
executed. Allow callers to decide whether they need the LFENCE or not. This
adds a few extra bytes to the call sites, but it obviates the need for
multiple variants of clear_bhb_loop().
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Jon Kohler <jon@nutanix.com>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
---
arch/x86/entry/entry_64.S | 5 ++++-
arch/x86/include/asm/nospec-branch.h | 4 ++--
arch/x86/net/bpf_jit_comp.c | 2 ++
3 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 42447b1e1dff..3a180a36ca0e 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1528,6 +1528,9 @@ SYM_CODE_END(rewind_stack_and_make_dead)
* refactored in the future if needed. The .skips are for safety, to ensure
* that all RETs are in the second half of a cacheline to mitigate Indirect
* Target Selection, rather than taking the slowpath via its_return_thunk.
+ *
+ * Note, callers should use a speculation barrier like LFENCE immediately after
+ * a call to this function to ensure BHB is cleared before indirect branches.
*/
SYM_FUNC_START(clear_bhb_loop)
ANNOTATE_NOENDBR
@@ -1562,7 +1565,7 @@ SYM_FUNC_START(clear_bhb_loop)
sub $1, %ecx
jnz 1b
.Lret2: RET
-5: lfence
+5:
pop %rbp
RET
SYM_FUNC_END(clear_bhb_loop)
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 4f4b5e8a1574..70b377fcbc1c 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -331,11 +331,11 @@
#ifdef CONFIG_X86_64
.macro CLEAR_BRANCH_HISTORY
- ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_LOOP
+ ALTERNATIVE "", "call clear_bhb_loop; lfence", X86_FEATURE_CLEAR_BHB_LOOP
.endm
.macro CLEAR_BRANCH_HISTORY_VMEXIT
- ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_VMEXIT
+ ALTERNATIVE "", "call clear_bhb_loop; lfence", X86_FEATURE_CLEAR_BHB_VMEXIT
.endm
#else
#define CLEAR_BRANCH_HISTORY
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index e9b78040d703..63d6c9fa5e80 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1624,6 +1624,8 @@ static int emit_spectre_bhb_barrier(u8 **pprog, u8 *ip,
if (emit_call(&prog, func, ip))
return -EINVAL;
+ /* Don't speculate past this until BHB is cleared */
+ EMIT_LFENCE();
EMIT1(0x59); /* pop rcx */
EMIT1(0x58); /* pop rax */
}
--
2.34.1
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