CHECK: Comparison to NULL could be written "!pchan->chan.shmem"
#45: FILE: drivers/mailbox/pcc.c:282:
+	if (pchan->chan.shmem == NULL) {

CHECK: extern prototypes should be avoided in .h files
#143: FILE: include/acpi/pcc.h:41:
+extern int pcc_mbox_ioremap(struct mbox_chan *chan);

total: 0 errors, 0 warnings, 2 checks, 117 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit aca2d87fd92a ("pcc: Check before sending MCTP PCC response ACK") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 0 warnings, 2 checks, 117 lines checked