Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

[platform/kernel/linux-starfive.git] / drivers / fpga / fpga-mgr.c

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 2526163..a24f5cb 100644 (file)
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -38,7 +38,8 @@ static struct class *fpga_mgr_class;
  *
  * Step the low level fpga manager through the device-specific steps of getting
  * an FPGA ready to be configured, writing the image to it, then doing whatever
- * post-configuration steps necessary.
+ * post-configuration steps necessary.  This code assumes the caller got the
+ * mgr pointer from of_fpga_mgr_get() and checked that it is not an error code.
  *
  * Return: 0 on success, negative error code otherwise.
  */
@@ -48,9 +49,6 @@ int fpga_mgr_buf_load(struct fpga_manager *mgr, u32 flags, const char *buf,
        struct device *dev = &mgr->dev;
        int ret;
 
-       if (!mgr)
-               return -ENODEV;
-
        /*
         * Call the low level driver's write_init function.  This will do the
         * device-specific things to get the FPGA into the state where it is
@@ -100,7 +98,8 @@ EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
  *
  * Request an FPGA image using the firmware class, then write out to the FPGA.
  * Update the state before each step to provide info on what step failed if
- * there is a failure.
+ * there is a failure.  This code assumes the caller got the mgr pointer
+ * from of_fpga_mgr_get() and checked that it is not an error code.
  *
  * Return: 0 on success, negative error code otherwise.
  */
@@ -111,9 +110,6 @@ int fpga_mgr_firmware_load(struct fpga_manager *mgr, u32 flags,
        const struct firmware *fw;
        int ret;
 
-       if (!mgr)
-               return -ENODEV;
-
        dev_info(dev, "writing %s to %s\n", image_name, mgr->name);
 
        mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ;
@@ -204,9 +200,7 @@ struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
 {
        struct fpga_manager *mgr;
        struct device *dev;
-
-       if (!node)
-               return ERR_PTR(-EINVAL);
+       int ret = -ENODEV;
 
        dev = class_find_device(fpga_mgr_class, NULL, node,
                                fpga_mgr_of_node_match);
@@ -214,20 +208,25 @@ struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
                return ERR_PTR(-ENODEV);
 
        mgr = to_fpga_manager(dev);
-       put_device(dev);
        if (!mgr)
-               return ERR_PTR(-ENODEV);
+               goto err_dev;
 
        /* Get exclusive use of fpga manager */
-       if (!mutex_trylock(&mgr->ref_mutex))
-               return ERR_PTR(-EBUSY);
-
-       if (!try_module_get(THIS_MODULE)) {
-               mutex_unlock(&mgr->ref_mutex);
-               return ERR_PTR(-ENODEV);
+       if (!mutex_trylock(&mgr->ref_mutex)) {
+               ret = -EBUSY;
+               goto err_dev;
        }
 
+       if (!try_module_get(dev->parent->driver->owner))
+               goto err_ll_mod;
+
        return mgr;
+
+err_ll_mod:
+       mutex_unlock(&mgr->ref_mutex);
+err_dev:
+       put_device(dev);
+       return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
 
@@ -237,10 +236,9 @@ EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
  */
 void fpga_mgr_put(struct fpga_manager *mgr)
 {
-       if (mgr) {
-               module_put(THIS_MODULE);
-               mutex_unlock(&mgr->ref_mutex);
-       }
+       module_put(mgr->dev.parent->driver->owner);
+       mutex_unlock(&mgr->ref_mutex);
+       put_device(&mgr->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_put);