[PATCH v2 3/4] VFIO: platform: populate the reset function on probe
Eric Auger
eric.auger at linaro.org
Fri Jun 5 08:06:31 PDT 2015
The reset function lookup happens on vfio-platform probe. The reset
module load is requested and a reference to the function symbol is
hold. The reference is released on vfio-platform remove.
Signed-off-by: Eric Auger <eric.auger at linaro.org>
---
v1 -> v2:
- [get,put]_reset now is called once on probe/remove
- use request_module to automatically load the reset module that
matches the compatibility string
- lookup table is used instead of list
- remove registration mechanism: reset function name is stored in the
lookup table.
- use device_property_read_string instead of
device_property_read_string_array
---
drivers/vfio/platform/vfio_platform_common.c | 48 +++++++++++++++++++++++++++-
1 file changed, 47 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 995929b..d474d6a 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -31,6 +31,47 @@ static const struct vfio_platform_reset_combo reset_lookup_table[] = {
},
};
+static int vfio_platform_get_reset(struct vfio_platform_device *vdev,
+ struct device *dev)
+{
+ const char *compat;
+ const struct vfio_platform_reset_combo *iter = reset_lookup_table;
+ int (*reset)(struct vfio_platform_device *);
+ int ret;
+
+ vdev->type = VFIO_PLATFORM_RESET_TYPE_MAX;
+ ret = device_property_read_string(dev, "compatible", &compat);
+ if (ret)
+ return ret;
+
+ while (iter->type < VFIO_PLATFORM_RESET_TYPE_MAX) {
+ if (!strcmp(iter->compat, compat)) {
+ request_module(iter->module_name);
+ reset = __symbol_get(iter->reset_function_name);
+ if (reset) {
+ vdev->type = iter->type;
+ vdev->reset = reset;
+ return 0;
+ }
+ }
+ iter++;
+ }
+ return -1;
+}
+
+static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
+{
+ const struct vfio_platform_reset_combo *iter = reset_lookup_table;
+
+ while (iter->type < VFIO_PLATFORM_RESET_TYPE_MAX) {
+ if (iter->type == vdev->type) {
+ __symbol_put(iter->reset_function_name);
+ return;
+ }
+ iter++;
+ }
+}
+
static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
{
int cnt = 0, i;
@@ -519,6 +560,8 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
return ret;
}
+ vfio_platform_get_reset(vdev, dev);
+
mutex_init(&vdev->igate);
return 0;
@@ -530,8 +573,11 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
struct vfio_platform_device *vdev;
vdev = vfio_del_group_dev(dev);
- if (vdev)
+
+ if (vdev) {
+ vfio_platform_put_reset(vdev);
iommu_group_put(dev->iommu_group);
+ }
return vdev;
}
--
1.9.1
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