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, 57 insertions, 0 deletions

diff --git a/include/trace/syscall.h b/include/trace/syscall.h
new file mode 100644
index 000000000..0dd7f2b33
--- /dev/null
+++ b/include/trace/syscall.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _TRACE_SYSCALL_H
+#define _TRACE_SYSCALL_H
+
+#include <linux/tracepoint.h>
+#include <linux/unistd.h>
+#include <linux/trace_events.h>
+#include <linux/thread_info.h>
+
+#include <asm/ptrace.h>
+
+
+/*
+ * A syscall entry in the ftrace syscalls array.
+ *
+ * @name: name of the syscall
+ * @syscall_nr: number of the syscall
+ * @nb_args: number of parameters it takes
+ * @user_arg_is_str: set if the arg for @user_arg_size is a string
+ * @user_arg_size: holds @arg that has size of the user space to read
+ * @user_mask: mask of @args that will read user space
+ * @types: list of types as strings
+ * @args: list of args as strings (args[i] matches types[i])
+ * @enter_fields: list of fields for syscall_enter trace event
+ * @enter_event: associated syscall_enter trace event
+ * @exit_event: associated syscall_exit trace event
+ */
+struct syscall_metadata {
+	const char	*name;
+	int		syscall_nr;
+	u8		nb_args:7;
+	u8		user_arg_is_str:1;
+	s8		user_arg_size;
+	short		user_mask;
+	const char	**types;
+	const char	**args;
+	struct list_head enter_fields;
+
+	struct trace_event_call *enter_event;
+	struct trace_event_call *exit_event;
+};
+
+#if defined(CONFIG_TRACEPOINTS) && defined(CONFIG_HAVE_SYSCALL_TRACEPOINTS)
+static inline void syscall_tracepoint_update(struct task_struct *p)
+{
+	if (test_syscall_work(SYSCALL_TRACEPOINT))
+		set_task_syscall_work(p, SYSCALL_TRACEPOINT);
+	else
+		clear_task_syscall_work(p, SYSCALL_TRACEPOINT);
+}
+#else
+static inline void syscall_tracepoint_update(struct task_struct *p)
+{
+}
+#endif
+
+#endif /* _TRACE_SYSCALL_H */