[PATCH v2 5/6] bus: fsl-mc: add root dprc rescan attribute

From: Ioana Ciornei
Date: Thu Mar 15 2018 - 13:07:40 EST


Introduce the rescan attribute as a device attribute to
synchronize the fsl-mc bus objects and the MC firmware.

To rescan the root dprc only, e.g.
echo 1 > /sys/bus/fsl-mc/devices/dprc.1/rescan

Signed-off-by: Ioana Ciornei <ioana.ciornei@xxxxxxx>
---
Changes in v2:
- added proper documentation in /Documentation/ABI/
- updated the MAINTAINERS file

Documentation/ABI/stable/sysfs-bus-fsl-mc | 6 ++++++
MAINTAINERS | 1 +
drivers/bus/fsl-mc/dprc-driver.c | 4 ++--
drivers/bus/fsl-mc/fsl-mc-bus.c | 28 ++++++++++++++++++++++++++++
drivers/bus/fsl-mc/fsl-mc-private.h | 3 +++
5 files changed, 40 insertions(+), 2 deletions(-)
create mode 100644 Documentation/ABI/stable/sysfs-bus-fsl-mc

diff --git a/Documentation/ABI/stable/sysfs-bus-fsl-mc b/Documentation/ABI/stable/sysfs-bus-fsl-mc
new file mode 100644
index 0000000..e530e8c
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-bus-fsl-mc
@@ -0,0 +1,6 @@
+What: /sys/bus/fsl-mc/devices/dprc.*/rescan
+Date: March. 2018
+KernelVersion: 4.16
+Contact: Ioana Ciornei <ioana.ciornei@xxxxxxx>
+Description: Root dprc rescan attribute
+Users: Userspace drivers and management tools
diff --git a/MAINTAINERS b/MAINTAINERS
index 4f54765..1268b42 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11464,6 +11464,7 @@ F: drivers/bus/fsl-mc/
F: Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
F: Documentation/networking/dpaa2/overview.rst
F: include/uapi/linux/fsl_mc.h
+F: Documentation/ABI/stable/sysfs-bus-fsl-mc

QT1010 MEDIA DRIVER
M: Antti Palosaari <crope@xxxxxx>
diff --git a/drivers/bus/fsl-mc/dprc-driver.c b/drivers/bus/fsl-mc/dprc-driver.c
index 52c7e15..be80e3a 100644
--- a/drivers/bus/fsl-mc/dprc-driver.c
+++ b/drivers/bus/fsl-mc/dprc-driver.c
@@ -214,8 +214,8 @@ static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
* populated before they can get allocation requests from probe callbacks
* of the device drivers for the non-allocatable devices.
*/
-static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
- unsigned int *total_irq_count)
+int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
+ unsigned int *total_irq_count)
{
int num_child_objects;
int dprc_get_obj_failures;
diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
index 0ade415..9d02984 100644
--- a/drivers/bus/fsl-mc/fsl-mc-bus.c
+++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
@@ -137,8 +137,36 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RO(modalias);

+static ssize_t rescan_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct fsl_mc_device *root_mc_dev;
+ struct fsl_mc_bus *root_mc_bus;
+ unsigned long val;
+
+ if (!fsl_mc_is_root_dprc(dev))
+ return -EINVAL;
+
+ root_mc_dev = to_fsl_mc_device(dev);
+ root_mc_bus = to_fsl_mc_bus(root_mc_dev);
+
+ if (kstrtoul(buf, 0, &val) < 0)
+ return -EINVAL;
+
+ if (val) {
+ mutex_lock(&root_mc_bus->scan_mutex);
+ dprc_scan_objects(root_mc_dev, NULL);
+ mutex_unlock(&root_mc_bus->scan_mutex);
+ }
+
+ return count;
+}
+static DEVICE_ATTR_WO(rescan);
+
static struct attribute *fsl_mc_dev_attrs[] = {
&dev_attr_modalias.attr,
+ &dev_attr_rescan.attr,
NULL,
};

diff --git a/drivers/bus/fsl-mc/fsl-mc-private.h b/drivers/bus/fsl-mc/fsl-mc-private.h
index 00cca7d..c1fc80e 100644
--- a/drivers/bus/fsl-mc/fsl-mc-private.h
+++ b/drivers/bus/fsl-mc/fsl-mc-private.h
@@ -545,6 +545,9 @@ int __must_check fsl_mc_device_add(struct fsl_mc_obj_desc *obj_desc,

void dprc_driver_exit(void);

+int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
+ unsigned int *total_irq_count);
+
int __init fsl_mc_allocator_driver_init(void);

void fsl_mc_allocator_driver_exit(void);
--
1.9.1