usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stopgrafted

cc_debounce_dwork is queued from the set_cc() and start_toggling()
callbacks, which run from TCPM's kthread worker.  port_stop() returns
before tcpm_unregister_port() destroys that worker.  Flushing the worker
during unregister may therefore run a callback which queues the delayed
work after port_stop() has returned.

The delayed work can then run after devres has freed pmic_typec_port.

Use disable_delayed_work_sync() in port_stop() to cancel a pending
instance and prevent the TCPM callbacks from queueing another one.

This issue was found by an in-house static analysis tool.

Fixes: a4422ff22142 ("usb: typec: qcom: Add Qualcomm PMIC Type-C driver")
Cc: stable <stable@kernel.org>  # v6.10+
Assisted-by: Codex:gpt-5.6
Signed-off-by: Fan Wu <fanwu01@zju.edu.cn>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20260820135307.153773-2-fanwu01@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/tools/perf/util/pstack.c b/tools/perf/util/pstack.c
new file mode 100644
index 000000000..141ffa129
--- /dev/null
+++ b/tools/perf/util/pstack.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple pointer stack
+ *
+ * (c) 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
+ */
+
+#include "pstack.h"
+#include "debug.h"
+#include <linux/kernel.h>
+#include <linux/zalloc.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct pstack {
+	unsigned short	top;
+	unsigned short	max_nr_entries;
+	void		*entries[];
+};
+
+struct pstack *pstack__new(unsigned short max_nr_entries)
+{
+	struct pstack *pstack = zalloc((sizeof(*pstack) +
+				       max_nr_entries * sizeof(void *)));
+	if (pstack != NULL)
+		pstack->max_nr_entries = max_nr_entries;
+	return pstack;
+}
+
+void pstack__delete(struct pstack *pstack)
+{
+	free(pstack);
+}
+
+bool pstack__empty(const struct pstack *pstack)
+{
+	return pstack->top == 0;
+}
+
+void pstack__remove(struct pstack *pstack, void *key)
+{
+	unsigned short i = pstack->top, last_index = pstack->top - 1;
+
+	while (i-- != 0) {
+		if (pstack->entries[i] == key) {
+			if (i < last_index)
+				memmove(pstack->entries + i,
+					pstack->entries + i + 1,
+					(last_index - i) * sizeof(void *));
+			--pstack->top;
+			return;
+		}
+	}
+	pr_err("%s: %p not on the pstack!\n", __func__, key);
+}
+
+void pstack__push(struct pstack *pstack, void *key)
+{
+	if (pstack->top == pstack->max_nr_entries) {
+		pr_err("%s: top=%d, overflow!\n", __func__, pstack->top);
+		return;
+	}
+	pstack->entries[pstack->top++] = key;
+}
+
+void *pstack__peek(struct pstack *pstack)
+{
+	if (pstack->top == 0)
+		return NULL;
+	return pstack->entries[pstack->top - 1];
+}