Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 164 insertions, 0 deletions

diff --git a/net/802/psnap.c b/net/802/psnap.c
new file mode 100644
index 000000000..8ae835e1c
--- /dev/null
+++ b/net/802/psnap.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	SNAP data link layer. Derived from 802.2
+ *
+ *		Alan Cox <alan@lxorguk.ukuu.org.uk>,
+ *		from the 802.2 layer by Greg Page.
+ *		Merged in additions from Greg Page's psnap.c.
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <net/datalink.h>
+#include <net/llc.h>
+#include <net/psnap.h>
+#include <linux/mm.h>
+#include <linux/in.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+
+static LIST_HEAD(snap_list);
+static DEFINE_SPINLOCK(snap_lock);
+static struct llc_sap *snap_sap;
+
+/*
+ *	Find a snap client by matching the 5 bytes.
+ */
+static struct datalink_proto *find_snap_client(const unsigned char *desc)
+{
+	struct datalink_proto *proto = NULL, *p;
+
+	list_for_each_entry_rcu(p, &snap_list, node, lockdep_is_held(&snap_lock)) {
+		if (!memcmp(p->type, desc, 5)) {
+			proto = p;
+			break;
+		}
+	}
+	return proto;
+}
+
+/*
+ *	A SNAP packet has arrived
+ */
+static int snap_rcv(struct sk_buff *skb, struct net_device *dev,
+		    struct packet_type *pt, struct net_device *orig_dev)
+{
+	int rc = 1;
+	struct datalink_proto *proto;
+	static struct packet_type snap_packet_type = {
+		.type = cpu_to_be16(ETH_P_SNAP),
+	};
+
+	if (unlikely(!pskb_may_pull(skb, 5)))
+		goto drop;
+
+	rcu_read_lock();
+	proto = find_snap_client(skb->data);
+	if (proto) {
+		/* Pass the frame on. */
+		skb_pull_rcsum(skb, 5);
+		skb_reset_transport_header(skb);
+		rc = proto->rcvfunc(skb, dev, &snap_packet_type, orig_dev);
+	}
+	rcu_read_unlock();
+
+	if (unlikely(!proto))
+		goto drop;
+
+out:
+	return rc;
+
+drop:
+	kfree_skb(skb);
+	goto out;
+}
+
+/*
+ *	Put a SNAP header on a frame and pass to 802.2
+ */
+static int snap_request(struct datalink_proto *dl,
+			struct sk_buff *skb, const u8 *dest)
+{
+	memcpy(skb_push(skb, 5), dl->type, 5);
+	llc_build_and_send_ui_pkt(snap_sap, skb, dest, snap_sap->laddr.lsap);
+	return 0;
+}
+
+/*
+ *	Set up the SNAP layer
+ */
+EXPORT_SYMBOL(register_snap_client);
+EXPORT_SYMBOL(unregister_snap_client);
+
+static const char snap_err_msg[] __initconst =
+	KERN_CRIT "SNAP - unable to register with 802.2\n";
+
+static int __init snap_init(void)
+{
+	snap_sap = llc_sap_open(0xAA, snap_rcv);
+	if (!snap_sap) {
+		printk(snap_err_msg);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+module_init(snap_init);
+
+static void __exit snap_exit(void)
+{
+	llc_sap_put(snap_sap);
+}
+
+module_exit(snap_exit);
+
+
+/*
+ *	Register SNAP clients. We don't yet use this for IP.
+ */
+struct datalink_proto *register_snap_client(const unsigned char *desc,
+					    int (*rcvfunc)(struct sk_buff *,
+							   struct net_device *,
+							   struct packet_type *,
+							   struct net_device *))
+{
+	struct datalink_proto *proto = NULL;
+
+	spin_lock_bh(&snap_lock);
+
+	if (find_snap_client(desc))
+		goto out;
+
+	proto = kmalloc_obj(*proto, GFP_ATOMIC);
+	if (proto) {
+		memcpy(proto->type, desc, 5);
+		proto->rcvfunc		= rcvfunc;
+		proto->header_length	= 5 + 3; /* snap + 802.2 */
+		proto->request		= snap_request;
+		list_add_rcu(&proto->node, &snap_list);
+	}
+out:
+	spin_unlock_bh(&snap_lock);
+
+	return proto;
+}
+
+/*
+ *	Unregister SNAP clients. Protocols no longer want to play with us ...
+ */
+void unregister_snap_client(struct datalink_proto *proto)
+{
+	spin_lock_bh(&snap_lock);
+	list_del_rcu(&proto->node);
+	spin_unlock_bh(&snap_lock);
+
+	synchronize_net();
+
+	kfree(proto);
+}
+
+MODULE_DESCRIPTION("SNAP data link layer. Derived from 802.2");
+MODULE_LICENSE("GPL");