| Message ID | 1427406371-6699-1-git-send-email-mathieu.poirier@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 30 March 2015 at 08:19, Alexander Shishkin <alexander.shishkin@linux.intel.com> wrote: > Mathieu Poirier <mathieu.poirier@linaro.org> writes: > >> Hey Alex, > > Hi Mathieu, > >> Have a look at the following patch and see if you agree with my approach. If so >> simply add the code to a third version. > > Greg's comment about the two levels of ioctls got me thinking in the > direction of adding callbacks to stm_data on case-by-case basis and then > I realized that we might actually move these private callbacks into the > stm core as well (see my followup to the coresight-stm driver patch). > > So, I suggest that we work through the ioctl commands that you need for > coresight stm and try to see how they fit into the generic scheme of > things and if we still find that we need implementation-specific ioctl > commands, then we try to shape them as individual callbacks rather than > just .ioctl(). Yeah, I'm pretty sure we can come up with something better here. > >> diff --git a/include/linux/stm.h b/include/linux/stm.h >> index 976c94d8f17f..84dd83c47fe7 100644 >> --- a/include/linux/stm.h >> +++ b/include/linux/stm.h >> @@ -62,8 +62,9 @@ struct stm_data { >> unsigned int); >> void (*unlink)(struct stm_data *, unsigned int, >> unsigned int); >> - long (*ioctl)(struct stm_data *, unsigned int, >> - unsigned long); >> + long (*ioctl)(struct stm_data *, >> + unsigned int, unsigned int, >> + unsigned int, unsigned long); > > We might go even further and pass a struct stm_output (which also > contains number of channels) pointer here, having first moved it from > drivers/... to include/linux/stm.h, and while at it also do the same to > the other callbacks that pass master/channel around. Does this make > sense to you? Humm... Do callbacks really need to have access to a struct output? From my side of the fence dealing with individual master/channels is sufficient but other people may have different scenarios. The end result is the same and modifying the callback signature doesn't represent a lot of work. > > Regards, > -- > Alex -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 9e82634590dc..ca71b06bbfea 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -511,9 +511,17 @@ stm_char_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return stm_char_policy_get_ioctl(stmf, (void __user *)arg); default: - if (stm_data->ioctl) - err = stm_data->ioctl(stm_data, cmd, arg); + if (stm_data->ioctl) { + /* users shouldn't call device specific ioctl before + * getting a channel using the proper potocol + */ + if (!stmf->output.nr_chans) + return -EINVAL; + err = stm_data->ioctl(stm_data, stmf->output.master, + stmf->output.channel, cmd, arg); + + } break; } diff --git a/include/linux/stm.h b/include/linux/stm.h index 976c94d8f17f..84dd83c47fe7 100644 --- a/include/linux/stm.h +++ b/include/linux/stm.h @@ -62,8 +62,9 @@ struct stm_data { unsigned int); void (*unlink)(struct stm_data *, unsigned int, unsigned int); - long (*ioctl)(struct stm_data *, unsigned int, - unsigned long); + long (*ioctl)(struct stm_data *, + unsigned int, unsigned int, + unsigned int, unsigned long); }; int stm_register_device(struct device *parent, struct stm_data *stm_data,