* [PATCH 1/2] hwmon: (asus_rog_ryujin) Fix pump control source on the Ryujin III
[not found] <20260927120927.72810-1-lanzonza@gmail.com>
@ 2026-09-27 12:09 ` Zac Lanzon
0 siblings, 0 replies; only message in thread
From: Zac Lanzon @ 2026-09-27 12:09 UTC (permalink / raw)
To: linux-hwmon
Cc: Guenter Roeck, Aleksa Savic, Edward Blair, Jonathan Corbet,
Shuah Khan, Randy Dunlap, linux-doc, linux-kernel, Zac Lanzon,
stable
The RYUJIN III pump has a 4-pin cable for a motherboard fan header in
addition to USB. Byte 2 of the set cooler duty command selects the pump
control source: 0 hands the pump to its internal controller, which
follows the PWM of the header its 4-pin cable is plugged into, and 1
makes it follow the pump duty in byte 3. Byte 3 of the cooler duty
report returns the current source.
The driver fills byte 2 with duty_channel, which is 1 for the RYUJIN
III, and a pwm2 write re-sends the reported pump duty with the new fan
duty. So writing only the internal fan duty takes the pump away from
its internal controller.
Measured on a RYUJIN III 360 (firmware AURJ2-S750-0108) with the pump
cable on AIO_PUMP and the header PWM set through nct6775, after loading
the driver with the pump on its internal controller (pump rpm):
header 50% header 80% source
no write yet 2160 3090 0
pwm2 = 40%, before this patch 1740 1740 1
pwm2 = 40%, with this patch 2130 3090 0
Send the reported source with pwm2 writes. The fan duty applies with
either source (40%: 1545 to 1590 rpm, 30%: 870 rpm). A pwm2 write sent
right after a pwm1 write that took the pump over, before the report
could show the change, left the pump on USB and applied its fan duty
(2 of 2 trials, and 7 of 7 with raw commands up to 0.9 s after).
pwm1 writes keep selecting source 1. The cooler reports the pump duty of
the last write, whichever source it selected, and 40% after power-on.
Byte 9 of the status report follows the duty the pump runs at. Measured
from power-on (PSU switched off) once per driver, with the header at
100%:
before this patch with this patch
source duty rpm source duty rpm
no write yet 0 100 3570 0 100 3570
pwm2 = 40% 1 100 3570 0 100 3570
pwm1 = 40%, the reported duty 1 100 3570 1 40 1710
pwm1 = 60% 1 60 2430
pwm1 = 40% 1 40 1725
So a pwm1 write of the reported duty did not reach the pump, while
other duties applied in one write, also when taking the pump from its
internal controller (60%: 2460 rpm). When a pwm1 write requests the
reported duty, write a duty 1% away first (below at 100%), then the
requested one. Sent back to back, the two writes left the pump at the
requested duty in all 19 trials, 9 with raw commands and 10 through
this driver.
Tested on the RYUJIN III 360 only. The EXTREME, EVA and WHITE EDITION
use the same rog_ryujin_iii_info and send the same command, and Edward
Blair's analysis of the WHITE EDITION firmware shows the same pump
control source. The RYUJIN II, whose duty_channel is 0, is unchanged.
Fixes: cd258aca0dc4 ("hwmon: (asus_rog_ryujin) Add ROG Ryujin III support")
Closes: https://github.com/aleksamagicka/asus_rog_ryujin-hwmon/issues/12
Suggested-by: Edward Blair <edward.blair@gmail.com>
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Zac Lanzon <lanzonza@gmail.com>
---
Documentation/hwmon/asus_rog_ryujin.rst | 6 +++
drivers/hwmon/asus_rog_ryujin.c | 54 ++++++++++++++++++++++++-
2 files changed, 59 insertions(+), 1 deletion(-)
diff --git a/Documentation/hwmon/asus_rog_ryujin.rst b/Documentation/hwmon/asus_rog_ryujin.rst
index 3ebab230e8c..fe072e94d87 100644
--- a/Documentation/hwmon/asus_rog_ryujin.rst
+++ b/Documentation/hwmon/asus_rog_ryujin.rst
@@ -34,6 +34,12 @@ Usage notes
As these are USB HIDs, the driver can be loaded automatically by the kernel and
supports hot swapping.
+The pump of the RYUJIN III also has a 4-pin cable for a motherboard fan header.
+The cooler either hands the pump to its internal controller, which follows the
+PWM of the header its 4-pin cable is plugged into, or runs it at the pump duty
+set over USB. Writing pwm1 selects the duty set over USB. Writing pwm2 sets
+only the internal fan duty and leaves the pump control as it is.
+
Sysfs entries
-------------
diff --git a/drivers/hwmon/asus_rog_ryujin.c b/drivers/hwmon/asus_rog_ryujin.c
index 5ced69e94ea..ba188e86793 100644
--- a/drivers/hwmon/asus_rog_ryujin.c
+++ b/drivers/hwmon/asus_rog_ryujin.c
@@ -50,6 +50,7 @@ static const struct rog_ryujin_device_info rog_ryujin_iii_info = {
#define MAX_REPORT_LENGTH 65
/* Cooler duty report offsets */
+#define RYUJIN_PUMP_SOURCE 3
#define RYUJIN_PUMP_DUTY 4
#define RYUJIN_INTERNAL_FAN_DUTY 5
@@ -70,10 +71,15 @@ static const u8 get_cooler_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x9A };
static const u8 get_controller_speed_cmd[] = { RYUJIN_CMD_PREFIX, 0xA0 };
static const u8 get_controller_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0xA1 };
+#define RYUJIN_SET_COOLER_CHANNEL_OFFSET 2
#define RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET 3
#define RYUJIN_SET_COOLER_FAN_DUTY_OFFSET 4
static const u8 set_cooler_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x1A, 0x00, 0x00, 0x00 };
+/* Pump control sources in the set cooler duty command and the cooler duty report */
+#define RYUJIN_SOURCE_HEADER 0
+#define RYUJIN_SOURCE_USB 1
+
#define RYUJIN_SET_CONTROLLER_FAN_DUTY_OFFSET 4
static const u8 set_controller_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x21, 0x00, 0x00, 0x00 };
@@ -117,6 +123,7 @@ struct rog_ryujin_data {
s32 temp_input[1];
u16 speed_input[6]; /* Pump, internal fan and four controller fan speeds in RPM */
u8 duty_input[3]; /* Pump, internal fan and controller fan duty in PWM */
+ u8 pump_source; /* Pump control source from the cooler duty report */
u8 *buffer;
unsigned long updated; /* jiffies */
@@ -306,6 +313,44 @@ static int rog_ryujin_read_string(struct device *dev, enum hwmon_sensor_types ty
return 0;
}
+/*
+ * On devices with a non-zero duty_channel (the RYUJIN III), the channel byte of
+ * the set cooler duty command selects the pump control source.
+ * RYUJIN_SOURCE_HEADER hands the pump to its internal controller, which follows
+ * the PWM of the header its 4-pin cable is plugged into. RYUJIN_SOURCE_USB
+ * makes the pump follow the pump duty in the command. The cooler duty report
+ * returns the current source.
+ *
+ * A fan duty write sends the reported source back, so that it leaves the pump
+ * control source as it is. A pump duty write selects USB. The cooler does not
+ * pass on a pump duty equal to the one it reports, and after power-on it
+ * reports 40% while a pump handed over at that duty runs at full speed. So
+ * when a pump duty write asks for the reported duty, write a duty 1% away
+ * first.
+ */
+static int rog_ryujin_select_pump_source(struct rog_ryujin_data *priv, u8 *set_cmd,
+ int channel)
+{
+ u8 duty = set_cmd[RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET];
+ int ret;
+
+ if (channel == 1) {
+ set_cmd[RYUJIN_SET_COOLER_CHANNEL_OFFSET] = priv->pump_source;
+ return 0;
+ }
+
+ set_cmd[RYUJIN_SET_COOLER_CHANNEL_OFFSET] = RYUJIN_SOURCE_USB;
+
+ if (duty != rog_ryujin_pwm_to_percent(priv->duty_input[0]))
+ return 0;
+
+ set_cmd[RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET] = duty < 100 ? duty + 1 : duty - 1;
+ ret = rog_ryujin_execute_cmd(priv, set_cmd, SET_CMD_LENGTH, &priv->cooler_duty_set);
+ set_cmd[RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET] = duty;
+
+ return ret;
+}
+
static int rog_ryujin_write_fixed_duty(struct rog_ryujin_data *priv, int channel, int val)
{
u8 set_cmd[SET_CMD_LENGTH];
@@ -323,7 +368,7 @@ static int rog_ryujin_write_fixed_duty(struct rog_ryujin_data *priv, int channel
return ret;
memcpy(set_cmd, set_cooler_duty_cmd, SET_CMD_LENGTH);
- set_cmd[2] = priv->info->duty_channel;
+ set_cmd[RYUJIN_SET_COOLER_CHANNEL_OFFSET] = priv->info->duty_channel;
/* Cooler duties are set as 0-100% */
val = rog_ryujin_pwm_to_percent(val);
@@ -340,6 +385,12 @@ static int rog_ryujin_write_fixed_duty(struct rog_ryujin_data *priv, int channel
set_cmd[RYUJIN_SET_COOLER_FAN_DUTY_OFFSET] = val;
}
+ if (priv->info->duty_channel) {
+ ret = rog_ryujin_select_pump_source(priv, set_cmd, channel);
+ if (ret < 0)
+ return ret;
+ }
+
return rog_ryujin_execute_cmd(priv, set_cmd, SET_CMD_LENGTH, &priv->cooler_duty_set);
} else {
/*
@@ -482,6 +533,7 @@ static int rog_ryujin_raw_event(struct hid_device *hdev, struct hid_report *repo
goto unlock;
}
read_cooler_duty:
+ priv->pump_source = data[RYUJIN_PUMP_SOURCE];
priv->duty_input[0] = rog_ryujin_percent_to_pwm(data[RYUJIN_PUMP_DUTY]);
priv->duty_input[1] = rog_ryujin_percent_to_pwm(data[RYUJIN_INTERNAL_FAN_DUTY]);
--
2.53.0
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