diff mbox series

[RFC,2/2] firmware: arm_scmi: Add bus support for autoloading

Message ID 20250203100154.140877-2-cristian.marussi@arm.com (mailing list archive)
State New
Headers show
Series [RFC,1/2] firmware: arm_scmi: Generate aliases for SCMI modules | expand

Commit Message

Cristian Marussi Feb. 3, 2025, 10:01 a.m. UTC
Emit proper MODALIAS uevents when SCMI devices are created and make sure
all the standard protocol devices are requested when the bus is
initialized.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
 drivers/firmware/arm_scmi/bus.c | 52 +++++++++++++++++++++++++++++----
 1 file changed, 47 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index def41fe3b161..dfa4fde2a81c 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -92,12 +92,17 @@  static int scmi_protocol_device_request(const struct scmi_device_id *id_table)
 				phead = head;
 		}
 		list_for_each_entry(rdev, head, node) {
+			/*
+			 * HACK
+			 * We ignore requested duplicates since they could have
+			 * been pre-requested...
+			 */
 			if (!strcmp(rdev->id_table->name, id_table->name)) {
-				pr_err("Ignoring duplicate request [%d] %s\n",
-				       rdev->id_table->protocol_id,
-				       rdev->id_table->name);
-				ret = -EINVAL;
-				goto out;
+				pr_debug("Device already requested [%d] %s\n",
+				        rdev->id_table->protocol_id,
+				        rdev->id_table->name);
+				mutex_unlock(&scmi_requested_devices_mtx);
+				return 0;
 			}
 		}
 	}
@@ -274,6 +279,16 @@  static struct scmi_device *scmi_child_dev_find(struct device *parent,
 	return to_scmi_dev(dev);
 }
 
+static int scmi_dev_uevent(const struct device *dev,
+			   struct kobj_uevent_env *env)
+{
+	const struct scmi_device *sdev = to_scmi_dev(dev);
+
+	add_uevent_var(env, "MODALIAS=scmi:pr%02X", sdev->protocol_id);
+
+	return 0;
+}
+
 static int scmi_dev_probe(struct device *dev)
 {
 	struct scmi_driver *scmi_drv = to_scmi_driver(dev->driver);
@@ -297,6 +312,7 @@  static void scmi_dev_remove(struct device *dev)
 const struct bus_type scmi_bus_type = {
 	.name =	"scmi_protocol",
 	.match = scmi_dev_match,
+	.uevent	= scmi_dev_uevent,
 	.probe = scmi_dev_probe,
 	.remove = scmi_dev_remove,
 };
@@ -516,6 +532,23 @@  static void scmi_devices_unregister(void)
 	bus_for_each_dev(&scmi_bus_type, NULL, NULL, __scmi_devices_unregister);
 }
 
+/* Standard protocols table */
+static const struct scmi_device_id scmi_std_id_table[] = {
+	{ SCMI_PROTOCOL_POWER, "genpd" },
+	{ SCMI_PROTOCOL_SYSTEM, "syspower" },
+	{ SCMI_PROTOCOL_PERF, "perf" },
+	{ SCMI_PROTOCOL_PERF, "cpufreq" },
+	{ SCMI_PROTOCOL_CLOCK, "clocks" },
+	{ SCMI_PROTOCOL_SENSOR, "hwmon" },
+	{ SCMI_PROTOCOL_SENSOR, "iiodev" },
+	{ SCMI_PROTOCOL_RESET, "reset" },
+	{ SCMI_PROTOCOL_VOLTAGE,  "regulator" },
+	{ SCMI_PROTOCOL_POWERCAP, "powercap" },
+	{ SCMI_PROTOCOL_PINCTRL, "pinctrl" },
+	{ SCMI_PROTOCOL_PINCTRL, "pinctrl-imx" },
+	{ },
+};
+
 static int __init scmi_bus_init(void)
 {
 	int retval;
@@ -526,6 +559,15 @@  static int __init scmi_bus_init(void)
 
 	pr_info("SCMI protocol bus registered\n");
 
+	/* HACK pre-request ALL standard protocol devices */
+	retval = scmi_protocol_table_register(scmi_std_id_table);
+	if (retval) {
+		bus_unregister(&scmi_bus_type);
+		return retval;
+	}
+
+	pr_info("SCMI standard protocols devices requested\n");
+
 	return retval;
 }
 subsys_initcall(scmi_bus_init);