iio: proximity: vl53l0x-i2c: claim direct mode for raw readsgrafted

vl53l0x_read_raw() starts a single-shot ranging measurement and reads
back the result. Once the triggered buffer is enabled the sensor runs in
continuous mode and its data-ready interrupt is routed to the trigger,
so a concurrent in_distance_raw read disturbs the streaming setup and
never gets its completion, returning -ETIMEDOUT.

The original submission claimed direct mode here, but it was dropped
during review because the driver had no buffer support at the time [1].
Continuous (buffered) mode was later added without restoring the
claim [2], reintroducing the conflict.

Reject direct reads while buffered capture is active by claiming direct
mode around the measurement, as the vl53l1x sibling already does.

Fixes: 762186c6e7b1 ("iio: proximity: vl53l0x-i2c: Added continuous mode support")
Link: https://lore.kernel.org/linux-iio/20180911160300.GA9212@himanshu-Vostro-3559/ [1]
Link: https://lore.kernel.org/linux-iio/20240909101508.263085-3-abhashkumarjha123@gmail.com/ [2]
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/include/uapi/asm-generic/msgbuf.h b/include/uapi/asm-generic/msgbuf.h
new file mode 100644
index 000000000..6504d7b74
--- /dev/null
+++ b/include/uapi/asm-generic/msgbuf.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef __ASM_GENERIC_MSGBUF_H
+#define __ASM_GENERIC_MSGBUF_H
+
+#include <asm/bitsperlong.h>
+#include <asm/ipcbuf.h>
+
+/*
+ * generic msqid64_ds structure.
+ *
+ * Note extra padding because this structure is passed back and forth
+ * between kernel and user space.
+ *
+ * msqid64_ds was originally meant to be architecture specific, but
+ * everyone just ended up making identical copies without specific
+ * optimizations, so we may just as well all use the same one.
+ *
+ * 64 bit architectures use a 64-bit long time field here, while
+ * 32 bit architectures have a pair of unsigned long values.
+ * On big-endian systems, the lower half is in the wrong place.
+ *
+ * Pad space is left for:
+ * - 2 miscellaneous 32-bit values
+ */
+
+struct msqid64_ds {
+	struct ipc64_perm msg_perm;
+#if __BITS_PER_LONG == 64
+	long		 msg_stime;	/* last msgsnd time */
+	long		 msg_rtime;	/* last msgrcv time */
+	long		 msg_ctime;	/* last change time */
+#else
+	unsigned long	msg_stime;	/* last msgsnd time */
+	unsigned long	msg_stime_high;
+	unsigned long	msg_rtime;	/* last msgrcv time */
+	unsigned long	msg_rtime_high;
+	unsigned long	msg_ctime;	/* last change time */
+	unsigned long	msg_ctime_high;
+#endif
+	unsigned long	msg_cbytes;	/* current number of bytes on queue */
+	unsigned long	msg_qnum;	/* number of messages in queue */
+	unsigned long	 msg_qbytes;	/* max number of bytes on queue */
+	__kernel_pid_t msg_lspid;	/* pid of last msgsnd */
+	__kernel_pid_t msg_lrpid;	/* last receive pid */
+	unsigned long	 __unused4;
+	unsigned long	 __unused5;
+};
+
+#endif /* __ASM_GENERIC_MSGBUF_H */