fpga: mgr: API change to replace fpga load functions with single function

fpga-mgr has three methods for programming FPGAs, depending on
whether the image is in a scatter gather list, a contiguous
buffer, or a firmware file. This makes it difficult to write
upper layers as the caller has to assume whether the FPGA image
is in a sg table, as a single buffer, or a firmware file.
This commit moves these parameters to struct fpga_image_info
and adds a single function for programming fpgas.

New functions:
* fpga_mgr_load - given fpga manager and struct fpga_image_info,
   program the fpga.

* fpga_image_info_alloc - alloc a struct fpga_image_info.

* fpga_image_info_free - free a struct fpga_image_info.

These three functions are unexported:
* fpga_mgr_buf_load_sg
* fpga_mgr_buf_load
* fpga_mgr_firmware_load

Also use devm_kstrdup to copy firmware_name so we aren't making
assumptions about where it comes from when allocing/freeing the
struct fpga_image_info.

API documentation has been updated and a new document for
FPGA region has been added.

Signed-off-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 85 insertions, 26 deletions

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 188ffefa3cc3..a8dd54945470 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -2,6 +2,7 @@
  * FPGA Manager Core
  *
  *  Copyright (C) 2013-2015 Altera Corporation
+ *  Copyright (C) 2017 Intel Corporation
  *
  * With code from the mailing list:
  * Copyright (C) 2013 Xilinx, Inc.
@@ -31,6 +32,40 @@
 static DEFINE_IDA(fpga_mgr_ida);
 static struct class *fpga_mgr_class;
 
+struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
+{
+	struct fpga_image_info *info;
+
+	get_device(dev);
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info) {
+		put_device(dev);
+		return NULL;
+	}
+
+	info->dev = dev;
+
+	return info;
+}
+EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
+
+void fpga_image_info_free(struct fpga_image_info *info)
+{
+	struct device *dev;
+
+	if (!info)
+		return;
+
+	dev = info->dev;
+	if (info->firmware_name)
+		devm_kfree(dev, info->firmware_name);
+
+	devm_kfree(dev, info);
+	put_device(dev);
+}
+EXPORT_SYMBOL_GPL(fpga_image_info_free);
+
 /*
  * 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 ready to
@@ -137,8 +172,9 @@ static int fpga_mgr_write_complete(struct fpga_manager *mgr,
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
-			 struct sg_table *sgt)
+static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
+				struct fpga_image_info *info,
+				struct sg_table *sgt)
 {
 	int ret;
 
@@ -170,7 +206,6 @@ int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
 
 	return fpga_mgr_write_complete(mgr, info);
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_buf_load_sg);
 
 static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
 				    struct fpga_image_info *info,
@@ -210,8 +245,9 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
-		      const char *buf, size_t count)
+static int fpga_mgr_buf_load(struct fpga_manager *mgr,
+			     struct fpga_image_info *info,
+			     const char *buf, size_t count)
 {
 	struct page **pages;
 	struct sg_table sgt;
@@ -266,7 +302,6 @@ int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
 
 /**
  * fpga_mgr_firmware_load - request firmware and load to fpga
@@ -282,9 +317,9 @@ EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_firmware_load(struct fpga_manager *mgr,
-			   struct fpga_image_info *info,
-			   const char *image_name)
+static int fpga_mgr_firmware_load(struct fpga_manager *mgr,
+				  struct fpga_image_info *info,
+				  const char *image_name)
 {
 	struct device *dev = &mgr->dev;
 	const struct firmware *fw;
@@ -307,7 +342,18 @@ int fpga_mgr_firmware_load(struct fpga_manager *mgr,
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load);
+
+int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info)
+{
+	if (info->sgt)
+		return fpga_mgr_buf_load_sg(mgr, info, info->sgt);
+	if (info->buf && info->count)
+		return fpga_mgr_buf_load(mgr, info, info->buf, info->count);
+	if (info->firmware_name)
+		return fpga_mgr_firmware_load(mgr, info, info->firmware_name);
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_load);
 
 static const char * const state_str[] = {
 	[FPGA_MGR_STATE_UNKNOWN] =		"unknown",
@@ -578,7 +624,7 @@ static void __exit fpga_mgr_class_exit(void)
 	ida_destroy(&fpga_mgr_ida);
 }
 
-MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
 MODULE_DESCRIPTION("FPGA manager framework");
 MODULE_LICENSE("GPL v2");
 
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 9175556215b1..120c496eb7bd 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -226,14 +226,11 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 /**
  * fpga_region_program_fpga - program FPGA
  * @region: FPGA region
- * @firmware_name: name of FPGA image firmware file
  * @overlay: device node of the overlay
- * Program an FPGA using information in the device tree.
- * Function assumes that there is a firmware-name property.
+ * Program an FPGA using information in the region's fpga image info.
  * Return 0 for success or negative error code.
  */
 static int fpga_region_program_fpga(struct fpga_region *region,
-				    const char *firmware_name,
 				    struct device_node *overlay)
 {
 	struct fpga_manager *mgr;
@@ -264,7 +261,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
-	ret = fpga_mgr_firmware_load(mgr, region->info, firmware_name);
+	ret = fpga_mgr_load(mgr, region->info);
 	if (ret) {
 		pr_err("failed to load fpga image\n");
 		goto err_put_br;
@@ -357,16 +354,15 @@ static int child_regions_with_firmware(struct device_node *overlay)
 static int fpga_region_notify_pre_apply(struct fpga_region *region,
 					struct of_overlay_notify_data *nd)
 {
-	const char *firmware_name = NULL;
+	struct device *dev = &region->dev;
 	struct fpga_image_info *info;
+	const char *firmware_name;
 	int ret;
 
-	info = devm_kzalloc(&region->dev, sizeof(*info), GFP_KERNEL);
+	info = fpga_image_info_alloc(dev);
 	if (!info)
 		return -ENOMEM;
 
-	region->info = info;
-
 	/* Reject overlay if child FPGA Regions have firmware-name property */
 	ret = child_regions_with_firmware(nd->overlay);
 	if (ret)
@@ -382,7 +378,13 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	if (of_property_read_bool(nd->overlay, "encrypted-fpga-config"))
 		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
 
-	of_property_read_string(nd->overlay, "firmware-name", &firmware_name);
+	if (!of_property_read_string(nd->overlay, "firmware-name",
+				     &firmware_name)) {
+		info->firmware_name = devm_kstrdup(dev, firmware_name,
+						   GFP_KERNEL);
+		if (!info->firmware_name)
+			return -ENOMEM;
+	}
 
 	of_property_read_u32(nd->overlay, "region-unfreeze-timeout-us",
 			     &info->enable_timeout_us);
@@ -394,22 +396,33 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 			     &info->config_complete_timeout_us);
 
 	/* If FPGA was externally programmed, don't specify firmware */
-	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && firmware_name) {
+	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && info->firmware_name) {
 		pr_err("error: specified firmware and external-fpga-config");
+		fpga_image_info_free(info);
 		return -EINVAL;
 	}
 
 	/* FPGA is already configured externally.  We're done. */
-	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG)
+	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
+		fpga_image_info_free(info);
 		return 0;
+	}
 
 	/* If we got this far, we should be programming the FPGA */
-	if (!firmware_name) {
+	if (!info->firmware_name) {
 		pr_err("should specify firmware-name or external-fpga-config\n");
+		fpga_image_info_free(info);
 		return -EINVAL;
 	}
 
-	return fpga_region_program_fpga(region, firmware_name, nd->overlay);
+	region->info = info;
+	ret = fpga_region_program_fpga(region, nd->overlay);
+	if (ret) {
+		fpga_image_info_free(info);
+		region->info = NULL;
+	}
+
+	return ret;
 }
 
 /**
@@ -426,7 +439,7 @@ static void fpga_region_notify_post_remove(struct fpga_region *region,
 {
 	fpga_bridges_disable(&region->bridge_list);
 	fpga_bridges_put(&region->bridge_list);
-	devm_kfree(&region->dev, region->info);
+	fpga_image_info_free(region->info);
 	region->info = NULL;
 }