spi: microchip-core-qspi: Add regular transfers

Merge series from Conor Dooley <conor@kernel.org>:

This is a v2 of a patchset I sent about this time last year, adding the
regular transfer_one_message op to the microchip-core-qspi driver. In that
v1 Mark expressed his dislike for that op, so v2 is using
prepare/unprepare/transfer_one instead. The unprepare implementation still
contains the 750 us delay that the driver had back in v1. I've heard a
suggestion internally as to why this is needed, but it was unsubstantiated,
so I still have no justification for it. I held off on sending a v2 because
of a lack of explanation for the delay, but I don't wanna hold off forever
for something I might never understand.

1 files changed, 8 insertions, 0 deletions

diff --git a/rust/helpers/cpu.c b/rust/helpers/cpu.c
new file mode 100644
index 000000000000..824e0adb19d4
--- /dev/null
+++ b/rust/helpers/cpu.c
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/smp.h>
+
+unsigned int rust_helper_raw_smp_processor_id(void)
+{
+	return raw_smp_processor_id();
+}