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, 80 insertions, 0 deletions

diff --git a/drivers/s390/char/ctrlchar.c b/drivers/s390/char/ctrlchar.c
new file mode 100644
index 000000000..6f2b64040
--- /dev/null
+++ b/drivers/s390/char/ctrlchar.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Unified handling of special chars.
+ *
+ *    Copyright IBM Corp. 2001
+ *    Author(s): Fritz Elfert <felfert@millenux.com> <elfert@de.ibm.com>
+ *
+ */
+
+#include <linux/stddef.h>
+#include <asm/errno.h>
+#include <linux/sysrq.h>
+#include <linux/ctype.h>
+
+#include "ctrlchar.h"
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static struct sysrq_work ctrlchar_sysrq;
+
+static void
+ctrlchar_handle_sysrq(struct work_struct *work)
+{
+	struct sysrq_work *sysrq = container_of(work, struct sysrq_work, work);
+
+	handle_sysrq(sysrq->key);
+}
+
+void schedule_sysrq_work(struct sysrq_work *sw)
+{
+	INIT_WORK(&sw->work, ctrlchar_handle_sysrq);
+	schedule_work(&sw->work);
+}
+#endif
+
+
+/**
+ * ctrlchar_handle - check for special chars at start of input
+ *
+ * @buf: console input buffer
+ * @len: length of valid data in buffer
+ * @tty: the tty struct for this console
+ *
+ * Return: CTRLCHAR_NONE, if nothing matched,
+ *         CTRLCHAR_SYSRQ, if sysrq was encountered
+ *         otherwise char to be inserted logically or'ed
+ *         with CTRLCHAR_CTRL
+ */
+unsigned int
+ctrlchar_handle(const unsigned char *buf, int len, struct tty_struct *tty)
+{
+	if ((len < 2) || (len > 3))
+		return CTRLCHAR_NONE;
+
+	/* hat is 0xb1 in codepage 037 (US etc.) and thus */
+	/* converted to 0x5e in ascii ('^') */
+	if ((buf[0] != '^') && (buf[0] != '\252'))
+		return CTRLCHAR_NONE;
+
+#ifdef CONFIG_MAGIC_SYSRQ
+	/* racy */
+	if (len == 3 && buf[1] == '-') {
+		ctrlchar_sysrq.key = buf[2];
+		schedule_sysrq_work(&ctrlchar_sysrq);
+		return CTRLCHAR_SYSRQ;
+	}
+#endif
+
+	if (len != 2)
+		return CTRLCHAR_NONE;
+
+	switch (tolower(buf[1])) {
+	case 'c':
+		return INTR_CHAR(tty) | CTRLCHAR_CTRL;
+	case 'd':
+		return EOF_CHAR(tty)  | CTRLCHAR_CTRL;
+	case 'z':
+		return SUSP_CHAR(tty) | CTRLCHAR_CTRL;
+	}
+	return CTRLCHAR_NONE;
+}