drivers: i3c: configure open-drain speed

Add support for configuring I3C open-drain speed modes to handle
different timing requirements during bus initialization and operation.

Implementation:
- Fetch current controller configuration
- Invoke configure api inside bus_init to configure
  I3C open-drain high period for proper bus
  initialization and device compatibility.

The slow speed mode is essential for the first broadcast address
transmission to ensure visibility to all devices on the I3C bus,
particularly those in I2C mode that need to disable their spike
filters when switching to I3C mode. This requirement is specified
in "Table 49 I3C Basic Open Drain Timing Parameters" of the MIPI
ALLIANCE Specification for I3C Basic Version 1.2.

Signed-off-by: Shreehari HK <[email protected]>

Author: Shreehari-AlifSemi

drivers/i3c/i3c_common.c

@@ -1350,6 +1350,32 @@ int i3c_bus_init(const struct device *dev, const struct i3c_dev_list *dev_list)
 	bool need_daa = true;
 	bool need_aasa = true;
 	struct i3c_ccc_events i3c_events;
+	struct i3c_config_controller ctrl_cfg;
+	uint32_t prev_od_high_ns;
+
+	/* Retrieve the active controller configuration */
+	ret = i3c_config_get_controller(dev, &ctrl_cfg);
+	if (ret != 0) {
+		LOG_ERR("%s: Failed to retrieve controller configuration", dev->name);
+		return ret;
+	}
+
+	/* Set OD high period for first broadcast message.
+	 * The Controller uses this timing to send the
+	 * first Broadcast Address, in order to disable the
+	 * I2C Spike Filter for applicable I3C Basic Target Devices.
+	 * Ref Section 4.3.2.2.2 and Table 49 of
+	 * MIPI ALLIANCE Specification for I3C Basic Version 1.2
+	 */
+	prev_od_high_ns = ctrl_cfg.scl_od_min.high_ns;
+	ctrl_cfg.scl_od_min.high_ns = MAX(I3C_OD_FIRST_BC_THIGH_MIN_NS,
+					ctrl_cfg.scl_od_min.high_ns);
+
+	ret = i3c_configure_controller(dev, &ctrl_cfg);
+	if (ret != 0) {
+		LOG_ERR("%s: Open Drain Slow speed set failed", dev->name);
+		return ret;
+	}
 
 #ifdef CONFIG_I3C_INIT_RSTACT
 	/*
@@ -1380,6 +1406,14 @@ int i3c_bus_init(const struct device *dev, const struct i3c_dev_list *dev_list)
 		LOG_DBG("Broadcast RSTDAA was NACK.");
 	}
 
+	/* Set previously stored OD high period back */
+	ctrl_cfg.scl_od_min.high_ns = prev_od_high_ns;
+	ret = i3c_configure_controller(dev, &ctrl_cfg);
+	if (ret != 0) {
+		LOG_ERR("%s: Open Drain Normal speed set failed", dev->name);
+		return ret;
+	}
+
 	/*
 	 * Disable all events from targets to avoid them
 	 * interfering with bus initialization,