[PATCH V3 1/6] stm class: Add ioctl get_options interface
From: Chunyan Zhang <hidden>
Date: 2016-02-06 11:06:16
Also in:
linux-api, lkml
Subsystem:
hardware tracing facilities, system trace module class, the rest · Maintainers:
Alexander Shishkin, Linus Torvalds
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 | 12 ++++++++++++ include/linux/stm.h | 3 +++ include/uapi/linux/stm.h | 1 + 3 files changed, 16 insertions(+)
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index b6445d9..854a16d 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c@@ -571,6 +571,18 @@ 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); + + if (copy_to_user((void __user *)arg, &options, sizeof(u64))) + return -EFAULT; + default: break; }
diff --git a/include/linux/stm.h b/include/linux/stm.h
index 9d0083d..f351d62 100644
--- a/include/linux/stm.h
+++ b/include/linux/stm.h@@ -88,6 +88,9 @@ struct stm_data { long (*set_options)(struct stm_data *, unsigned int, unsigned int, unsigned int, unsigned long); + long (*get_options)(struct stm_data *, unsigned int, + unsigned int, unsigned int, + u64 *); }; int stm_register_device(struct device *parent, struct stm_data *stm_data,
diff --git a/include/uapi/linux/stm.h b/include/uapi/linux/stm.h
index 626a8d3..0dab16e 100644
--- a/include/uapi/linux/stm.h
+++ b/include/uapi/linux/stm.h@@ -46,5 +46,6 @@ struct stp_policy_id { #define STP_POLICY_ID_SET _IOWR('%', 0, struct stp_policy_id) #define STP_POLICY_ID_GET _IOR('%', 1, struct stp_policy_id) #define STP_SET_OPTIONS _IOW('%', 2, __u64) +#define STP_GET_OPTIONS _IOR('%', 3, __u64) #endif /* _UAPI_LINUX_STM_H */
--
1.9.1