| Message ID | 1454487337-30184-2-git-send-email-zhang.chunyan@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Chunyan Zhang <zhang.chunyan@linaro.org> writes: > 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 <zhang.chunyan@linaro.org> > --- > 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)); The return value of copy_to_user() is not what you assume it is. Regards, -- Alex
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)); + 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 */
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 <zhang.chunyan@linaro.org> --- drivers/hwtracing/stm/core.c | 11 +++++++++++ include/linux/stm.h | 3 +++ include/uapi/linux/stm.h | 1 + 3 files changed, 15 insertions(+)