fpga: dfl: afu: convert platform_driver to use dev_groups

This patch takes advantage of driver core which helps to create
and remove sysfs attribute files, so there is no need to register
sysfs entries manually in dfl-afu platform river code.

Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Moritz Fischer <mdf@kernel.org>

1 files changed, 36 insertions, 33 deletions

diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c
index e50c45ed40ac..e955149722bd 100644
--- a/drivers/fpga/dfl-afu-main.c
+++ b/drivers/fpga/dfl-afu-main.c
@@ -282,24 +282,17 @@ static struct attribute *port_hdr_attrs[] = {
         &dev_attr_power_state.attr,
         NULL,
 };
-ATTRIBUTE_GROUPS(port_hdr);
+
+static const struct attribute_group port_hdr_group = {
+        .attrs = port_hdr_attrs,
+};
 
 static int port_hdr_init(struct platform_device *pdev,
                          struct dfl_feature *feature)
 {
-        dev_dbg(&pdev->dev, "PORT HDR Init.\n");
-
         port_reset(pdev);
 
-        return device_add_groups(&pdev->dev, port_hdr_groups);
-}
-
-static void port_hdr_uinit(struct platform_device *pdev,
-                           struct dfl_feature *feature)
-{
-        dev_dbg(&pdev->dev, "PORT HDR UInit.\n");
-
-        device_remove_groups(&pdev->dev, port_hdr_groups);
+        return 0;
 }
 
 static long
@@ -330,7 +323,6 @@ static const struct dfl_feature_id port_hdr_id_table[] = {
 
 static const struct dfl_feature_ops port_hdr_ops = {
         .init = port_hdr_init,
-        .uinit = port_hdr_uinit,
         .ioctl = port_hdr_ioctl,
 };
 
@@ -361,32 +353,37 @@ static struct attribute *port_afu_attrs[] = {
         &dev_attr_afu_id.attr,
         NULL
 };
-ATTRIBUTE_GROUPS(port_afu);
 
-static int port_afu_init(struct platform_device *pdev,
-                         struct dfl_feature *feature)
+static umode_t port_afu_attrs_visible(struct kobject *kobj,
+                                      struct attribute *attr, int n)
 {
-        struct resource *res = &pdev->resource[feature->resource_index];
-        int ret;
-
-        dev_dbg(&pdev->dev, "PORT AFU Init.\n");
+        struct device *dev = kobj_to_dev(kobj);
 
-        ret = afu_mmio_region_add(dev_get_platdata(&pdev->dev),
-                                  DFL_PORT_REGION_INDEX_AFU, resource_size(res),
-                                  res->start, DFL_PORT_REGION_READ |
-                                  DFL_PORT_REGION_WRITE | DFL_PORT_REGION_MMAP);
-        if (ret)
-                return ret;
+        /*
+         * sysfs entries are visible only if related private feature is
+         * enumerated.
+         */
+        if (!dfl_get_feature_by_id(dev, PORT_FEATURE_ID_AFU))
+                return 0;
 
-        return device_add_groups(&pdev->dev, port_afu_groups);
+        return attr->mode;
 }
 
-static void port_afu_uinit(struct platform_device *pdev,
-                           struct dfl_feature *feature)
+static const struct attribute_group port_afu_group = {
+        .attrs      = port_afu_attrs,
+        .is_visible = port_afu_attrs_visible,
+};
+
+static int port_afu_init(struct platform_device *pdev,
+                         struct dfl_feature *feature)
 {
-        dev_dbg(&pdev->dev, "PORT AFU UInit.\n");
+        struct resource *res = &pdev->resource[feature->resource_index];
 
-        device_remove_groups(&pdev->dev, port_afu_groups);
+        return afu_mmio_region_add(dev_get_platdata(&pdev->dev),
+                                   DFL_PORT_REGION_INDEX_AFU,
+                                   resource_size(res), res->start,
+                                   DFL_PORT_REGION_MMAP | DFL_PORT_REGION_READ |
+                                   DFL_PORT_REGION_WRITE);
 }
 
 static const struct dfl_feature_id port_afu_id_table[] = {
@@ -396,7 +393,6 @@ static const struct dfl_feature_id port_afu_id_table[] = {
 
 static const struct dfl_feature_ops port_afu_ops = {
         .init = port_afu_init,
-        .uinit = port_afu_uinit,
 };
 
 static struct dfl_feature_driver port_feature_drvs[] = {
@@ -748,9 +744,16 @@ static int afu_remove(struct platform_device *pdev)
         return 0;
 }
 
+static const struct attribute_group *afu_dev_groups[] = {
+        &port_hdr_group,
+        &port_afu_group,
+        NULL
+};
+
 static struct platform_driver afu_driver = {
         .driver = {
-                .name    = DFL_FPGA_FEATURE_DEV_PORT,
+                .name       = DFL_FPGA_FEATURE_DEV_PORT,
+                .dev_groups = afu_dev_groups,
         },
         .probe   = afu_probe,
         .remove  = afu_remove,