[PATCH v5 05/28] fpga: region: add compat_id support

Wu Hao
2018-05-02T02:50:08Z

This patch introduces a compat_id pointer member and sysfs interface
for each fpga region, similar as compat_id for fpga manager, it allows
applications to read the per region compat_id for compatibility
checking before other actions on this fpga-region (e.g PR).

Signed-off-by: Wu Hao <hao.wu@intel.com>
---
v5: use pointer for compat_id as it's optional to implement.
---
Documentation/ABI/testing/sysfs-class-fpga-region | 9 +++++++++
drivers/fpga/fpga-region.c | 22 ++++++++++++++++++++++
include/linux/fpga/fpga-region.h | 2 ++
3 files changed, 33 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-fpga-region

diff --git a/Documentation/ABI/testing/sysfs-class-fpga-region b/Documentation/ABI/testing/sysfs-class-fpga-region
new file mode 100644
index 0000000..9618f74
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-fpga-region
@@ -0,0 +1,9 @@
+What: /sys/class/fpga_region/<region>/compat_id
+Date: May 2018
+KernelVersion: 4.17
+Contact: Wu Hao <hao.wu@intel.com>
+Description: FPGA region id for compatibility check, e.g compatibility
+ of the FPGA reconfiguration hardware and image. This value
+ is defined or calculated by the layer that is creating the
+ FPGA region. This interface returns the compat_id value or
+ just error code -ENOENT in case compat_id is not used.
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index d6a9dd2..6929178 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -162,6 +162,27 @@ int fpga_region_program_fpga(struct fpga_region *region)
}
EXPORT_SYMBOL_GPL(fpga_region_program_fpga);

+static ssize_t compat_id_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fpga_region *region = to_fpga_region(dev);
+
+ if (!region->compat_id)
+ return -ENOENT;
+
+ return sprintf(buf, "%016llx%016llx\n",
+ (unsigned long long)region->compat_id->id_h,
+ (unsigned long long)region->compat_id->id_l);
+}
+
+static DEVICE_ATTR_RO(compat_id);
+
+static struct attribute *fpga_region_attrs[] = {
+ &dev_attr_compat_id.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(fpga_region);
+
/**
* fpga_region_create - alloc and init a struct fpga_region
* @dev: device parent
@@ -262,6 +283,7 @@ static int __init fpga_region_init(void)
if (IS_ERR(fpga_region_class))
return PTR_ERR(fpga_region_class);

+ fpga_region_class->dev_groups = fpga_region_groups;
fpga_region_class->dev_release = fpga_region_dev_release;

return 0;
diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
index f2e215b..e8ad979 100644
--- a/include/linux/fpga/fpga-region.h
+++ b/include/linux/fpga/fpga-region.h
@@ -12,6 +12,7 @@
* @bridge_list: list of FPGA bridges specified in region
* @mgr: FPGA manager
* @info: FPGA image info
+ * @compat_id: FPGA region id for compatibility check.
* @priv: private data
* @get_bridges: optional function to get bridges to a list
*/
@@ -21,6 +22,7 @@ struct fpga_region {
struct list_head bridge_list;
struct fpga_manager *mgr;
struct fpga_image_info *info;
+ struct fpga_compat_id *compat_id;
void *priv;
int (*get_bridges)(struct fpga_region *region);
};
--
1.8.3.1