gpu: nvgpu: Create sysfs symlinks

gk20a is going to be moved under platform bus, however, the sysfs
interface should remain stable over the transition period. This
patch adds a symlink to keep current interfaces stable.

Bug 1311528
Bug 1434573

Change-Id: I951000f4b25285ff96e93eb726342d5b76cc84f1
Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Reviewed-on: http://git-master/r/396926
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index f7e0a2b6..9ebc5bab 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
@@ -333,6 +333,8 @@ static DEVICE_ATTR(elpg_enable, ROOTRW, elpg_enable_read, elpg_enable_store);
 
 void gk20a_remove_sysfs(struct device *dev)
 {
+        struct gk20a *g = get_gk20a(to_platform_device(dev));
+
         device_remove_file(dev, &dev_attr_elcg_enable);
         device_remove_file(dev, &dev_attr_blcg_enable);
         device_remove_file(dev, &dev_attr_slcg_enable);
@@ -343,10 +345,14 @@ void gk20a_remove_sysfs(struct device *dev)
         device_remove_file(dev, &dev_attr_load);
         device_remove_file(dev, &dev_attr_railgate_delay);
         device_remove_file(dev, &dev_attr_clockgate_delay);
+
+        if (g->host1x_dev && (dev->parent != &g->host1x_dev->dev))
+                sysfs_remove_link(&dev->kobj, dev_name(dev));
 }
 
 void gk20a_create_sysfs(struct platform_device *dev)
 {
+        struct gk20a *g = get_gk20a(dev);
         int error = 0;
 
         error |= device_create_file(&dev->dev, &dev_attr_elcg_enable);
@@ -360,6 +366,12 @@ void gk20a_create_sysfs(struct platform_device *dev)
         error |= device_create_file(&dev->dev, &dev_attr_railgate_delay);
         error |= device_create_file(&dev->dev, &dev_attr_clockgate_delay);
 
+        if (g->host1x_dev && (dev->dev.parent != &g->host1x_dev->dev))
+                error |= sysfs_create_link(&g->host1x_dev->dev.kobj,
+                                           &dev->dev.kobj,
+                                           dev_name(&dev->dev));
+
         if (error)
                 dev_err(&dev->dev, "Failed to create sysfs attributes!\n");
+
 }