[PATCH v2 1/2] module: add SCMI device table alias support
From: Bjorn Andersson
Date: Thu Jun 18 2026 - 12:04:12 EST
SCMI client drivers already describe their bus match data with
MODULE_DEVICE_TABLE(scmi, ...), but modpost does not know how to consume
SCMI device tables. As a result, SCMI modules do not get generated module
aliases from their id tables.
Move struct scmi_device_id to mod_devicetable.h so it has a fixed layout
visible to modpost, add the corresponding generated offsets and teach
file2alias to emit scmi:<protocol>:<name> aliases.
Use the same stable alias format for SCMI device uevents and sysfs
modaliases. The previous string included the instance-specific device
name, which is not useful for matching modules.
Assisted-by: Codex:GPT-5.5
Reviewed-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>
---
drivers/clk/clk-scmi.c | 1 +
drivers/cpufreq/scmi-cpufreq.c | 1 +
drivers/firmware/arm_scmi/bus.c | 20 ++++++++++----------
drivers/firmware/arm_scmi/driver.c | 1 +
drivers/firmware/arm_scmi/scmi_power_control.c | 1 +
drivers/firmware/imx/sm-cpu.c | 1 +
drivers/firmware/imx/sm-lmm.c | 1 +
drivers/firmware/imx/sm-misc.c | 1 +
drivers/hwmon/scmi-hwmon.c | 1 +
drivers/iio/common/scmi_sensors/scmi_iio.c | 1 +
drivers/input/keyboard/imx-sm-bbm-key.c | 1 +
drivers/pmdomain/arm/scmi_perf_domain.c | 1 +
drivers/pmdomain/arm/scmi_pm_domain.c | 1 +
drivers/powercap/arm_scmi_powercap.c | 1 +
drivers/regulator/scmi-regulator.c | 1 +
drivers/reset/reset-scmi.c | 1 +
drivers/rtc/rtc-imx-sm-bbm.c | 1 +
include/linux/mod_devicetable.h | 11 +++++++++++
include/linux/scmi_protocol.h | 5 +----
scripts/mod/devicetable-offsets.c | 4 ++++
scripts/mod/file2alias.c | 11 +++++++++++
21 files changed, 53 insertions(+), 14 deletions(-)
diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 7c562559ad8b..b9e29e124302 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -11,6 +11,7 @@
#include <linux/err.h>
#include <linux/of.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/scmi_protocol.h>
#define NOT_ATOMIC false
diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 4edb4f7a8aa9..affa005bf8b1 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -15,6 +15,7 @@
#include <linux/energy_model.h>
#include <linux/export.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/pm_opp.h>
#include <linux/pm_qos.h>
diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index 793be9eabaed..70781146fa61 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -10,14 +10,16 @@
#include <linux/atomic.h>
#include <linux/types.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/kernel.h>
#include <linux/slab.h>
+#include <linux/string.h>
#include <linux/device.h>
#include "common.h"
-#define SCMI_UEVENT_MODALIAS_FMT "%s:%02x:%s"
+#define SCMI_UEVENT_MODALIAS_FMT SCMI_MODULE_PREFIX "%02x:%s"
BLOCKING_NOTIFIER_HEAD(scmi_requested_devices_nh);
EXPORT_SYMBOL_GPL(scmi_requested_devices_nh);
@@ -141,7 +143,7 @@ static int scmi_protocol_table_register(const struct scmi_device_id *id_table)
int ret = 0;
const struct scmi_device_id *entry;
- for (entry = id_table; entry->name && ret == 0; entry++)
+ for (entry = id_table; entry->name[0] && ret == 0; entry++)
ret = scmi_protocol_device_request(entry);
return ret;
@@ -197,18 +199,18 @@ scmi_protocol_table_unregister(const struct scmi_device_id *id_table)
{
const struct scmi_device_id *entry;
- for (entry = id_table; entry->name; entry++)
+ for (entry = id_table; entry->name[0]; entry++)
scmi_protocol_device_unrequest(entry);
}
static int scmi_dev_match_by_id_table(struct scmi_device *scmi_dev,
const struct scmi_device_id *id_table)
{
- if (!id_table || !id_table->name)
+ if (!id_table || !id_table->name[0])
return 0;
/* Always skip transport devices from matching */
- for (; id_table->protocol_id && id_table->name; id_table++)
+ for (; id_table->protocol_id && id_table->name[0]; id_table++)
if (id_table->protocol_id == scmi_dev->protocol_id &&
strncmp(scmi_dev->name, "__scmi_transport_device", 23) &&
!strcmp(id_table->name, scmi_dev->name))
@@ -245,7 +247,7 @@ static struct scmi_device *scmi_child_dev_find(struct device *parent,
struct device *dev;
id_table[0].protocol_id = prot_id;
- id_table[0].name = name;
+ strscpy(id_table[0].name, name, sizeof(id_table[0].name));
dev = device_find_child(parent, &id_table, scmi_match_by_id_table);
if (!dev)
@@ -282,8 +284,7 @@ static int scmi_device_uevent(const struct device *dev, struct kobj_uevent_env *
const struct scmi_device *scmi_dev = to_scmi_dev(dev);
return add_uevent_var(env, "MODALIAS=" SCMI_UEVENT_MODALIAS_FMT,
- dev_name(&scmi_dev->dev), scmi_dev->protocol_id,
- scmi_dev->name);
+ scmi_dev->protocol_id, scmi_dev->name);
}
static ssize_t modalias_show(struct device *dev,
@@ -292,8 +293,7 @@ static ssize_t modalias_show(struct device *dev,
struct scmi_device *scmi_dev = to_scmi_dev(dev);
return sysfs_emit(buf, SCMI_UEVENT_MODALIAS_FMT,
- dev_name(&scmi_dev->dev), scmi_dev->protocol_id,
- scmi_dev->name);
+ scmi_dev->protocol_id, scmi_dev->name);
}
static DEVICE_ATTR_RO(modalias);
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 3e0d975ec94c..0fd6a947499e 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -30,6 +30,7 @@
#include <linux/hashtable.h>
#include <linux/list.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/processor.h>
diff --git a/drivers/firmware/arm_scmi/scmi_power_control.c b/drivers/firmware/arm_scmi/scmi_power_control.c
index 955736336061..1900bb77383e 100644
--- a/drivers/firmware/arm_scmi/scmi_power_control.c
+++ b/drivers/firmware/arm_scmi/scmi_power_control.c
@@ -45,6 +45,7 @@
#include <linux/math.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/printk.h>
diff --git a/drivers/firmware/imx/sm-cpu.c b/drivers/firmware/imx/sm-cpu.c
index 091b014f739f..53a8d1cee5ea 100644
--- a/drivers/firmware/imx/sm-cpu.c
+++ b/drivers/firmware/imx/sm-cpu.c
@@ -5,6 +5,7 @@
#include <linux/firmware/imx/sm.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/scmi_protocol.h>
diff --git a/drivers/firmware/imx/sm-lmm.c b/drivers/firmware/imx/sm-lmm.c
index 6807bf563c03..f4dc198187a8 100644
--- a/drivers/firmware/imx/sm-lmm.c
+++ b/drivers/firmware/imx/sm-lmm.c
@@ -5,6 +5,7 @@
#include <linux/firmware/imx/sm.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/scmi_protocol.h>
diff --git a/drivers/firmware/imx/sm-misc.c b/drivers/firmware/imx/sm-misc.c
index ac9af824c2d4..5e39e79a9d8a 100644
--- a/drivers/firmware/imx/sm-misc.c
+++ b/drivers/firmware/imx/sm-misc.c
@@ -7,6 +7,7 @@
#include <linux/device/devres.h>
#include <linux/firmware/imx/sm.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/scmi_protocol.h>
diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c
index eec223d174c0..57b91e931c5d 100644
--- a/drivers/hwmon/scmi-hwmon.c
+++ b/drivers/hwmon/scmi-hwmon.c
@@ -8,6 +8,7 @@
#include <linux/hwmon.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/scmi_protocol.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c
index 442b40ef27cf..3babc4261965 100644
--- a/drivers/iio/common/scmi_sensors/scmi_iio.c
+++ b/drivers/iio/common/scmi_sensors/scmi_iio.c
@@ -15,6 +15,7 @@
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/scmi_protocol.h>
#include <linux/time.h>
diff --git a/drivers/input/keyboard/imx-sm-bbm-key.c b/drivers/input/keyboard/imx-sm-bbm-key.c
index 96486bd23d60..36e349136ee7 100644
--- a/drivers/input/keyboard/imx-sm-bbm-key.c
+++ b/drivers/input/keyboard/imx-sm-bbm-key.c
@@ -6,6 +6,7 @@
#include <linux/input.h>
#include <linux/jiffies.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
diff --git a/drivers/pmdomain/arm/scmi_perf_domain.c b/drivers/pmdomain/arm/scmi_perf_domain.c
index 3693423459c9..741375ad325b 100644
--- a/drivers/pmdomain/arm/scmi_perf_domain.c
+++ b/drivers/pmdomain/arm/scmi_perf_domain.c
@@ -8,6 +8,7 @@
#include <linux/err.h>
#include <linux/device.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/pm_domain.h>
#include <linux/pm_opp.h>
#include <linux/scmi_protocol.h>
diff --git a/drivers/pmdomain/arm/scmi_pm_domain.c b/drivers/pmdomain/arm/scmi_pm_domain.c
index 3d73aef21d2f..0948d05c9e3c 100644
--- a/drivers/pmdomain/arm/scmi_pm_domain.c
+++ b/drivers/pmdomain/arm/scmi_pm_domain.c
@@ -8,6 +8,7 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/pm_domain.h>
#include <linux/scmi_protocol.h>
diff --git a/drivers/powercap/arm_scmi_powercap.c b/drivers/powercap/arm_scmi_powercap.c
index ab66e9a3b1e2..332e4e26f1e5 100644
--- a/drivers/powercap/arm_scmi_powercap.c
+++ b/drivers/powercap/arm_scmi_powercap.c
@@ -10,6 +10,7 @@
#include <linux/limits.h>
#include <linux/list.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/powercap.h>
#include <linux/scmi_protocol.h>
#include <linux/slab.h>
diff --git a/drivers/regulator/scmi-regulator.c b/drivers/regulator/scmi-regulator.c
index c005e65ba0ec..f55f228cb133 100644
--- a/drivers/regulator/scmi-regulator.c
+++ b/drivers/regulator/scmi-regulator.c
@@ -25,6 +25,7 @@
#include <linux/linear_range.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c
index 4335811e0cfa..a6739df1d3c2 100644
--- a/drivers/reset/reset-scmi.c
+++ b/drivers/reset/reset-scmi.c
@@ -6,6 +6,7 @@
*/
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/of.h>
#include <linux/device.h>
#include <linux/reset-controller.h>
diff --git a/drivers/rtc/rtc-imx-sm-bbm.c b/drivers/rtc/rtc-imx-sm-bbm.c
index daa472be7c80..c8643718cef1 100644
--- a/drivers/rtc/rtc-imx-sm-bbm.c
+++ b/drivers/rtc/rtc-imx-sm-bbm.c
@@ -5,6 +5,7 @@
#include <linux/jiffies.h>
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/scmi_protocol.h>
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 3b0c9a251a2e..769382f2eadd 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -473,6 +473,17 @@ struct rpmsg_device_id {
kernel_ulong_t driver_data;
};
+/* scmi */
+
+#define SCMI_NAME_SIZE 32
+#define SCMI_MODULE_PREFIX "scmi:"
+
+struct scmi_device_id {
+ __u8 protocol_id;
+ char name[SCMI_NAME_SIZE];
+ kernel_ulong_t driver_data;
+};
+
/* i2c */
#define I2C_NAME_SIZE 20
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 5ab73b1ab9aa..61f5ecfe0133 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -951,10 +951,7 @@ struct scmi_device {
#define to_scmi_dev(d) container_of_const(d, struct scmi_device, dev)
-struct scmi_device_id {
- u8 protocol_id;
- const char *name;
-};
+struct scmi_device_id;
struct scmi_driver {
const char *name;
diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index b4178c42d08f..da5bd712c8da 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -144,6 +144,10 @@ int main(void)
DEVID(rpmsg_device_id);
DEVID_FIELD(rpmsg_device_id, name);
+ DEVID(scmi_device_id);
+ DEVID_FIELD(scmi_device_id, protocol_id);
+ DEVID_FIELD(scmi_device_id, name);
+
DEVID(i2c_device_id);
DEVID_FIELD(i2c_device_id, name);
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 8d36c74dec2d..a5283f4c8e6f 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -852,6 +852,16 @@ static void do_rpmsg_entry(struct module *mod, void *symval)
module_alias_printf(mod, false, RPMSG_DEVICE_MODALIAS_FMT, *name);
}
+/* Looks like: scmi:NN:S */
+static void do_scmi_entry(struct module *mod, void *symval)
+{
+ DEF_FIELD(symval, scmi_device_id, protocol_id);
+ DEF_FIELD_ADDR(symval, scmi_device_id, name);
+
+ module_alias_printf(mod, false, SCMI_MODULE_PREFIX "%02x:%s",
+ protocol_id, *name);
+}
+
/* Looks like: i2c:S */
static void do_i2c_entry(struct module *mod, void *symval)
{
@@ -1491,6 +1501,7 @@ static const struct devtable devtable[] = {
{"virtio", SIZE_virtio_device_id, do_virtio_entry},
{"vmbus", SIZE_hv_vmbus_device_id, do_vmbus_entry},
{"rpmsg", SIZE_rpmsg_device_id, do_rpmsg_entry},
+ {"scmi", SIZE_scmi_device_id, do_scmi_entry},
{"i2c", SIZE_i2c_device_id, do_i2c_entry},
{"i3c", SIZE_i3c_device_id, do_i3c_entry},
{"slim", SIZE_slim_device_id, do_slim_entry},
--
2.53.0