Re: [PATCH V2 1/6] stm class: Add ioctl get_options interface

There is already an interface of set_options, but no get_options yet.
Before setting any options, one would may want to see the current
status of that option by means of get_options interface. This
interface has been used in CoreSight STM driver.

Signed-off-by: Chunyan Zhang <redacted>
---
 drivers/hwtracing/stm/core.c | 11 +++++++++++
 include/linux/stm.h          |  3 +++
 include/uapi/linux/stm.h     |  1 +
 3 files changed, 15 insertions(+)

diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index b6445d9..86bb4e3 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c

@@ -571,6 +571,17 @@ stm_char_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 						    options);
 
 		break;
+
+	case STP_GET_OPTIONS:
+		if (stm_data->get_options)
+			err = stm_data->get_options(stm_data,
+						    stmf->output.master,
+						    stmf->output.channel,
+						    stmf->output.nr_chans,
+						    &options);
+
+		return copy_to_user((void __user *)arg, &options, sizeof(u64));