[PATCH 4/4] ptp: create "pins" together with the rest of attributes

Dmitry Torokhov
2017-02-14T03:51:34Z

Let's switch to using device_create_with_groups(), which will allow us to
create "pins" attribute group together with the rest of ptp device
attributes, and before userspace gets notified about ptp device creation.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
drivers/ptp/ptp_clock.c | 20 +++++++++++---------
drivers/ptp/ptp_private.h | 7 ++++---
drivers/ptp/ptp_sysfs.c | 39 +++++++++------------------------------
3 files changed, 24 insertions(+), 42 deletions(-)

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index b4e5e8022c29..e8142803a1a7 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -221,16 +221,17 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
mutex_init(&ptp->pincfg_mux);
init_waitqueue_head(&ptp->tsev_wq);

+ err = ptp_populate_pin_groups(ptp);
+ if (err)
+ goto no_pin_groups;
+
/* Create a new device in our class. */
- ptp->dev = device_create(ptp_class, parent, ptp->devid, ptp,
- "ptp%d", ptp->index);
+ ptp->dev = device_create_with_groups(ptp_class, parent, ptp->devid,
+ ptp, ptp->pin_attr_groups,
+ "ptp%d", ptp->index);
if (IS_ERR(ptp->dev))
goto no_device;

- err = ptp_populate_sysfs(ptp);
- if (err)
- goto no_sysfs;
-
/* Register a new PPS source. */
if (info->pps) {
struct pps_source_info pps;
@@ -258,10 +259,10 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
if (ptp->pps_source)
pps_unregister_source(ptp->pps_source);
no_pps:
- ptp_cleanup_sysfs(ptp);
-no_sysfs:
device_destroy(ptp_class, ptp->devid);
no_device:
+ ptp_cleanup_pin_groups(ptp);
+no_pin_groups:
mutex_destroy(&ptp->tsevq_mux);
mutex_destroy(&ptp->pincfg_mux);
ida_simple_remove(&ptp_clocks_map, index);
@@ -280,8 +281,9 @@ int ptp_clock_unregister(struct ptp_clock *ptp)
/* Release the clock's resources. */
if (ptp->pps_source)
pps_unregister_source(ptp->pps_source);
- ptp_cleanup_sysfs(ptp);
+
device_destroy(ptp_class, ptp->devid);
+ ptp_cleanup_pin_groups(ptp);

posix_clock_unregister(&ptp->clock);
return 0;
diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
index 9c5d41421b65..d95888974d0c 100644
--- a/drivers/ptp/ptp_private.h
+++ b/drivers/ptp/ptp_private.h
@@ -54,6 +54,8 @@ struct ptp_clock {
struct device_attribute *pin_dev_attr;
struct attribute **pin_attr;
struct attribute_group pin_attr_group;
+ /* 1st entry is a pointer to the real group, 2nd is NULL terminator */
+ const struct attribute_group *pin_attr_groups[2];
};

/*
@@ -94,8 +96,7 @@ uint ptp_poll(struct posix_clock *pc,

extern const struct attribute_group *ptp_groups[];

-int ptp_cleanup_sysfs(struct ptp_clock *ptp);
-
-int ptp_populate_sysfs(struct ptp_clock *ptp);
+int ptp_populate_pin_groups(struct ptp_clock *ptp);
+void ptp_cleanup_pin_groups(struct ptp_clock *ptp);

#endif
diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index a6292744c7ed..f8813ca8801c 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -268,25 +268,14 @@ static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
return count;
}

-int ptp_cleanup_sysfs(struct ptp_clock *ptp)
+int ptp_populate_pin_groups(struct ptp_clock *ptp)
{
- struct device *dev = ptp->dev;
- struct ptp_clock_info *info = ptp->info;
-
- if (info->n_pins) {
- sysfs_remove_group(&dev->kobj, &ptp->pin_attr_group);
- kfree(ptp->pin_attr);
- kfree(ptp->pin_dev_attr);
- }
- return 0;
-}
-
-static int ptp_populate_pins(struct ptp_clock *ptp)
-{
- struct device *dev = ptp->dev;
struct ptp_clock_info *info = ptp->info;
int err = -ENOMEM, i, n_pins = info->n_pins;

+ if (!n_pins)
+ return 0;
+
ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
GFP_KERNEL);
if (!ptp->pin_dev_attr)
@@ -313,28 +302,18 @@ static int ptp_populate_pins(struct ptp_clock *ptp)
ptp->pin_attr_group.name = "pins";
ptp->pin_attr_group.attrs = ptp->pin_attr;

- err = sysfs_create_group(&dev->kobj, &ptp->pin_attr_group);
- if (err)
- goto no_group;
+ ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
+
return 0;

-no_group:
- kfree(ptp->pin_attr);
no_pin_attr:
kfree(ptp->pin_dev_attr);
no_dev_attr:
return err;
}

-int ptp_populate_sysfs(struct ptp_clock *ptp)
+void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
{
- struct ptp_clock_info *info = ptp->info;
- int err;
-
- if (info->n_pins) {
- err = ptp_populate_pins(ptp);
- if (err)
- return err;
- }
- return 0;
+ kfree(ptp->pin_attr);
+ kfree(ptp->pin_dev_attr);
}
--
2.11.0.483.g087da7b7c-goog