1 files changed, 82 insertions, 47 deletions

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 9939d2cbc9a6..c1564cf827fe 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * FPGA Manager Core
  *
@@ -6,18 +7,6 @@
  *
  * With code from the mailing list:
  * Copyright (C) 2013 Xilinx, Inc.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <linux/firmware.h>
 #include <linux/fpga/fpga-mgr.h>
@@ -32,6 +21,12 @@
 static DEFINE_IDA(fpga_mgr_ida);
 static struct class *fpga_mgr_class;
 
+/**
+ * fpga_image_info_alloc - Allocate a FPGA image info struct
+ * @dev: owning device
+ *
+ * Return: struct fpga_image_info or NULL
+ */
 struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
 {
         struct fpga_image_info *info;
@@ -50,6 +45,10 @@ struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
 
+/**
+ * fpga_image_info_free - Free a FPGA image info struct
+ * @info: FPGA image info struct to free
+ */
 void fpga_image_info_free(struct fpga_image_info *info)
 {
         struct device *dev;
@@ -234,7 +233,7 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
 /**
  * fpga_mgr_buf_load - load fpga from image in buffer
  * @mgr:        fpga manager
- * @flags:      flags setting fpga confuration modes
+ * @info:       fpga image info
  * @buf:        buffer contain fpga image
  * @count:      byte count of buf
  *
@@ -343,6 +342,16 @@ static int fpga_mgr_firmware_load(struct fpga_manager *mgr,
         return ret;
 }
 
+/**
+ * fpga_mgr_load - load FPGA from scatter/gather table, buffer, or firmware
+ * @mgr:        fpga manager
+ * @info:       fpga image information.
+ *
+ * Load the FPGA from an image which is indicated in @info.  If successful, the
+ * FPGA ends up in operating mode.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
 int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info)
 {
         if (info->sgt)
@@ -429,11 +438,9 @@ static int fpga_mgr_dev_match(struct device *dev, const void *data)
 }
 
 /**
- * fpga_mgr_get - get a reference to a fpga mgr
+ * fpga_mgr_get - Given a device, get a reference to a fpga mgr.
  * @dev:        parent device that fpga mgr was registered with
  *
- * Given a device, get a reference to a fpga mgr.
- *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
 struct fpga_manager *fpga_mgr_get(struct device *dev)
@@ -453,10 +460,9 @@ static int fpga_mgr_of_node_match(struct device *dev, const void *data)
 }
 
 /**
- * of_fpga_mgr_get - get a reference to a fpga mgr
- * @node:       device node
+ * of_fpga_mgr_get - Given a device node, get a reference to a fpga mgr.
  *
- * Given a device node, get a reference to a fpga mgr.
+ * @node:       device node
  *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
@@ -489,7 +495,10 @@ EXPORT_SYMBOL_GPL(fpga_mgr_put);
  * @mgr:        fpga manager
  *
  * Given a pointer to FPGA Manager (from fpga_mgr_get() or
- * of_fpga_mgr_put()) attempt to get the mutex.
+ * of_fpga_mgr_put()) attempt to get the mutex. The user should call
+ * fpga_mgr_lock() and verify that it returns 0 before attempting to
+ * program the FPGA.  Likewise, the user should call fpga_mgr_unlock
+ * when done programming the FPGA.
  *
  * Return: 0 for success or -EBUSY
  */
@@ -505,7 +514,7 @@ int fpga_mgr_lock(struct fpga_manager *mgr)
 EXPORT_SYMBOL_GPL(fpga_mgr_lock);
 
 /**
- * fpga_mgr_unlock - Unlock FPGA manager
+ * fpga_mgr_unlock - Unlock FPGA manager after done programming
  * @mgr:        fpga manager
  */
 void fpga_mgr_unlock(struct fpga_manager *mgr)
@@ -515,17 +524,17 @@ void fpga_mgr_unlock(struct fpga_manager *mgr)
 EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
 
 /**
- * fpga_mgr_register - register a low level fpga manager driver
+ * fpga_mgr_create - create and initialize a FPGA manager struct
  * @dev:        fpga manager device from pdev
  * @name:       fpga manager name
  * @mops:       pointer to structure of fpga manager ops
  * @priv:       fpga manager private data
  *
- * Return: 0 on success, negative error code otherwise.
+ * Return: pointer to struct fpga_manager or NULL
  */
-int fpga_mgr_register(struct device *dev, const char *name,
-                      const struct fpga_manager_ops *mops,
-                      void *priv)
+struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
+                                     const struct fpga_manager_ops *mops,
+                                     void *priv)
 {
         struct fpga_manager *mgr;
         int id, ret;
@@ -534,17 +543,17 @@ int fpga_mgr_register(struct device *dev, const char *name,
             !mops->write_init || (!mops->write && !mops->write_sg) ||
             (mops->write && mops->write_sg)) {
                 dev_err(dev, "Attempt to register without fpga_manager_ops\n");
-                return -EINVAL;
+                return NULL;
         }
 
         if (!name || !strlen(name)) {
                 dev_err(dev, "Attempt to register with no name!\n");
-                return -EINVAL;
+                return NULL;
         }
 
         mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
         if (!mgr)
-                return -ENOMEM;
+                return NULL;
 
         id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
         if (id < 0) {
@@ -558,25 +567,56 @@ int fpga_mgr_register(struct device *dev, const char *name,
         mgr->mops = mops;
         mgr->priv = priv;
 
-        /*
-         * Initialize framework state by requesting low level driver read state
-         * from device.  FPGA may be in reset mode or may have been programmed
-         * by bootloader or EEPROM.
-         */
-        mgr->state = mgr->mops->state(mgr);
-
         device_initialize(&mgr->dev);
         mgr->dev.class = fpga_mgr_class;
         mgr->dev.groups = mops->groups;
         mgr->dev.parent = dev;
         mgr->dev.of_node = dev->of_node;
         mgr->dev.id = id;
-        dev_set_drvdata(dev, mgr);
 
         ret = dev_set_name(&mgr->dev, "fpga%d", id);
         if (ret)
                 goto error_device;
 
+        return mgr;
+
+error_device:
+        ida_simple_remove(&fpga_mgr_ida, id);
+error_kfree:
+        kfree(mgr);
+
+        return NULL;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_create);
+
+/**
+ * fpga_mgr_free - deallocate a FPGA manager
+ * @mgr:        fpga manager struct created by fpga_mgr_create
+ */
+void fpga_mgr_free(struct fpga_manager *mgr)
+{
+        ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
+        kfree(mgr);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_free);
+
+/**
+ * fpga_mgr_register - register a FPGA manager
+ * @mgr:        fpga manager struct created by fpga_mgr_create
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int fpga_mgr_register(struct fpga_manager *mgr)
+{
+        int ret;
+
+        /*
+         * Initialize framework state by requesting low level driver read state
+         * from device.  FPGA may be in reset mode or may have been programmed
+         * by bootloader or EEPROM.
+         */
+        mgr->state = mgr->mops->state(mgr);
+
         ret = device_add(&mgr->dev);
         if (ret)
                 goto error_device;
@@ -586,22 +626,18 @@ int fpga_mgr_register(struct device *dev, const char *name,
         return 0;
 
 error_device:
-        ida_simple_remove(&fpga_mgr_ida, id);
-error_kfree:
-        kfree(mgr);
+        ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
 
         return ret;
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_register);
 
 /**
- * fpga_mgr_unregister - unregister a low level fpga manager driver
- * @dev:        fpga manager device from pdev
+ * fpga_mgr_unregister - unregister and free a FPGA manager
+ * @mgr:        fpga manager struct
  */
-void fpga_mgr_unregister(struct device *dev)
+void fpga_mgr_unregister(struct fpga_manager *mgr)
 {
-        struct fpga_manager *mgr = dev_get_drvdata(dev);
-
         dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
 
         /*
@@ -619,8 +655,7 @@ static void fpga_mgr_dev_release(struct device *dev)
 {
         struct fpga_manager *mgr = to_fpga_manager(dev);
 
-        ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
-        kfree(mgr);
+        fpga_mgr_free(mgr);
 }
 
 static int __init fpga_mgr_class_init(void)