Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 995 insertions, 0 deletions

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
new file mode 100644
index 000000000..8efa67620
--- /dev/null
+++ b/drivers/fpga/fpga-mgr.c
@@ -0,0 +1,995 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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.
+ */
+#include <linux/firmware.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+
+static DEFINE_IDA(fpga_mgr_ida);
+static struct class *fpga_mgr_class;
+
+struct fpga_mgr_devres {
+	struct fpga_manager *mgr;
+};
+
+static inline void fpga_mgr_fpga_remove(struct fpga_manager *mgr)
+{
+	if (mgr->mops->fpga_remove)
+		mgr->mops->fpga_remove(mgr);
+}
+
+static inline enum fpga_mgr_states fpga_mgr_state(struct fpga_manager *mgr)
+{
+	if (mgr->mops->state)
+		return  mgr->mops->state(mgr);
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static inline u64 fpga_mgr_status(struct fpga_manager *mgr)
+{
+	if (mgr->mops->status)
+		return mgr->mops->status(mgr);
+	return 0;
+}
+
+static inline int fpga_mgr_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+	if (mgr->mops->write)
+		return  mgr->mops->write(mgr, buf, count);
+	return -EOPNOTSUPP;
+}
+
+/*
+ * After all the FPGA image has been written, do the device specific steps to
+ * finish and set the FPGA into operating mode.
+ */
+static inline int fpga_mgr_write_complete(struct fpga_manager *mgr,
+					  struct fpga_image_info *info)
+{
+	int ret = 0;
+
+	mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE;
+	if (mgr->mops->write_complete)
+		ret = mgr->mops->write_complete(mgr, info);
+	if (ret) {
+		dev_err(&mgr->dev, "Error after writing image data to FPGA\n");
+		mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE_ERR;
+		return ret;
+	}
+	mgr->state = FPGA_MGR_STATE_OPERATING;
+
+	return 0;
+}
+
+static inline int fpga_mgr_parse_header(struct fpga_manager *mgr,
+					struct fpga_image_info *info,
+					const char *buf, size_t count)
+{
+	if (mgr->mops->parse_header)
+		return mgr->mops->parse_header(mgr, info, buf, count);
+	return 0;
+}
+
+static inline int fpga_mgr_write_init(struct fpga_manager *mgr,
+				      struct fpga_image_info *info,
+				      const char *buf, size_t count)
+{
+	if (mgr->mops->write_init)
+		return  mgr->mops->write_init(mgr, info, buf, count);
+	return 0;
+}
+
+static inline int fpga_mgr_write_sg(struct fpga_manager *mgr,
+				    struct sg_table *sgt)
+{
+	if (mgr->mops->write_sg)
+		return  mgr->mops->write_sg(mgr, sgt);
+	return -EOPNOTSUPP;
+}
+
+/**
+ * fpga_image_info_alloc - Allocate an 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;
+
+	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);
+
+/**
+ * fpga_image_info_free - Free an FPGA image info struct
+ * @info: FPGA image info struct to free
+ */
+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 parse_header function with entire FPGA image
+ * buffer on the input. This will set info->header_size and info->data_size.
+ */
+static int fpga_mgr_parse_header_mapped(struct fpga_manager *mgr,
+					struct fpga_image_info *info,
+					const char *buf, size_t count)
+{
+	int ret;
+
+	mgr->state = FPGA_MGR_STATE_PARSE_HEADER;
+	ret = fpga_mgr_parse_header(mgr, info, buf, count);
+
+	if (info->header_size + info->data_size > count) {
+		dev_err(&mgr->dev, "Bitstream data outruns FPGA image\n");
+		ret = -EINVAL;
+	}
+
+	if (ret) {
+		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
+		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
+	}
+
+	return ret;
+}
+
+/*
+ * Call the low level driver's parse_header function with first fragment of
+ * scattered FPGA image on the input. If header fits first fragment,
+ * parse_header will set info->header_size and info->data_size. If it is not,
+ * parse_header will set desired size to info->header_size and -EAGAIN will be
+ * returned.
+ */
+static int fpga_mgr_parse_header_sg_first(struct fpga_manager *mgr,
+					  struct fpga_image_info *info,
+					  struct sg_table *sgt)
+{
+	struct sg_mapping_iter miter;
+	int ret;
+
+	mgr->state = FPGA_MGR_STATE_PARSE_HEADER;
+
+	sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
+	if (sg_miter_next(&miter) &&
+	    miter.length >= info->header_size)
+		ret = fpga_mgr_parse_header(mgr, info, miter.addr, miter.length);
+	else
+		ret = -EAGAIN;
+	sg_miter_stop(&miter);
+
+	if (ret && ret != -EAGAIN) {
+		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
+		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
+	}
+
+	return ret;
+}
+
+/*
+ * Copy scattered FPGA image fragments to temporary buffer and call the
+ * low level driver's parse_header function. This should be called after
+ * fpga_mgr_parse_header_sg_first() returned -EAGAIN. In case of success,
+ * pointer to the newly allocated image header copy will be returned and
+ * its size will be set into *ret_size. Returned buffer needs to be freed.
+ */
+static void *fpga_mgr_parse_header_sg(struct fpga_manager *mgr,
+				      struct fpga_image_info *info,
+				      struct sg_table *sgt, size_t *ret_size)
+{
+	size_t len, new_header_size, header_size = 0;
+	char *new_buf, *buf = NULL;
+	int ret;
+
+	do {
+		new_header_size = info->header_size;
+		if (new_header_size <= header_size) {
+			dev_err(&mgr->dev, "Requested invalid header size\n");
+			ret = -EFAULT;
+			break;
+		}
+
+		new_buf = krealloc(buf, new_header_size, GFP_KERNEL);
+		if (!new_buf) {
+			ret = -ENOMEM;
+			break;
+		}
+
+		buf = new_buf;
+
+		len = sg_pcopy_to_buffer(sgt->sgl, sgt->nents,
+					 buf + header_size,
+					 new_header_size - header_size,
+					 header_size);
+		if (len != new_header_size - header_size) {
+			ret = -EFAULT;
+			break;
+		}
+
+		header_size = new_header_size;
+		ret = fpga_mgr_parse_header(mgr, info, buf, header_size);
+	} while (ret == -EAGAIN);
+
+	if (ret) {
+		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
+		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
+		kfree(buf);
+		buf = ERR_PTR(ret);
+	}
+
+	*ret_size = header_size;
+
+	return buf;
+}
+
+/*
+ * 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
+ * receive an FPGA image. The low level driver gets to see at least first
+ * info->header_size bytes in the buffer. If info->header_size is 0,
+ * write_init will not get any bytes of image buffer.
+ */
+static int fpga_mgr_write_init_buf(struct fpga_manager *mgr,
+				   struct fpga_image_info *info,
+				   const char *buf, size_t count)
+{
+	size_t header_size = info->header_size;
+	int ret;
+
+	mgr->state = FPGA_MGR_STATE_WRITE_INIT;
+
+	if (header_size > count)
+		ret = -EINVAL;
+	else if (!header_size)
+		ret = fpga_mgr_write_init(mgr, info, NULL, 0);
+	else
+		ret = fpga_mgr_write_init(mgr, info, buf, count);
+
+	if (ret) {
+		dev_err(&mgr->dev, "Error preparing FPGA for writing\n");
+		mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR;
+		return ret;
+	}
+
+	return 0;
+}
+
+static int fpga_mgr_prepare_sg(struct fpga_manager *mgr,
+			       struct fpga_image_info *info,
+			       struct sg_table *sgt)
+{
+	struct sg_mapping_iter miter;
+	size_t len;
+	char *buf;
+	int ret;
+
+	/* Short path. Low level driver don't care about image header. */
+	if (!mgr->mops->initial_header_size && !mgr->mops->parse_header)
+		return fpga_mgr_write_init_buf(mgr, info, NULL, 0);
+
+	/*
+	 * First try to use miter to map the first fragment to access the
+	 * header, this is the typical path.
+	 */
+	ret = fpga_mgr_parse_header_sg_first(mgr, info, sgt);
+	/* If 0, header fits first fragment, call write_init on it */
+	if (!ret) {
+		sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
+		if (sg_miter_next(&miter)) {
+			ret = fpga_mgr_write_init_buf(mgr, info, miter.addr,
+						      miter.length);
+			sg_miter_stop(&miter);
+			return ret;
+		}
+		sg_miter_stop(&miter);
+	/*
+	 * If -EAGAIN, more sg buffer is needed,
+	 * otherwise an error has occurred.
+	 */
+	} else if (ret != -EAGAIN) {
+		return ret;
+	}
+
+	/*
+	 * Copy the fragments into temporary memory.
+	 * Copying is done inside fpga_mgr_parse_header_sg().
+	 */
+	buf = fpga_mgr_parse_header_sg(mgr, info, sgt, &len);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	ret = fpga_mgr_write_init_buf(mgr, info, buf, len);
+
+	kfree(buf);
+
+	return ret;
+}
+
+/**
+ * fpga_mgr_buf_load_sg - load fpga from image in buffer from a scatter list
+ * @mgr:	fpga manager
+ * @info:	fpga image specific information
+ * @sgt:	scatterlist table
+ *
+ * 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.  This code assumes the caller got the
+ * mgr pointer from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is
+ * not an error code.
+ *
+ * This is the preferred entry point for FPGA programming, it does not require
+ * any contiguous kernel memory.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
+				struct fpga_image_info *info,
+				struct sg_table *sgt)
+{
+	int ret;
+
+	ret = fpga_mgr_prepare_sg(mgr, info, sgt);
+	if (ret)
+		return ret;
+
+	/* Write the FPGA image to the FPGA. */
+	mgr->state = FPGA_MGR_STATE_WRITE;
+	if (mgr->mops->write_sg) {
+		ret = fpga_mgr_write_sg(mgr, sgt);
+	} else {
+		size_t length, count = 0, data_size = info->data_size;
+		struct sg_mapping_iter miter;
+
+		sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
+
+		if (mgr->mops->skip_header &&
+		    !sg_miter_skip(&miter, info->header_size)) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		while (sg_miter_next(&miter)) {
+			if (data_size)
+				length = min(miter.length, data_size - count);
+			else
+				length = miter.length;
+
+			ret = fpga_mgr_write(mgr, miter.addr, length);
+			if (ret)
+				break;
+
+			count += length;
+			if (data_size && count >= data_size)
+				break;
+		}
+		sg_miter_stop(&miter);
+	}
+
+out:
+	if (ret) {
+		dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
+		mgr->state = FPGA_MGR_STATE_WRITE_ERR;
+		return ret;
+	}
+
+	return fpga_mgr_write_complete(mgr, info);
+}
+
+static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
+				    struct fpga_image_info *info,
+				    const char *buf, size_t count)
+{
+	int ret;
+
+	ret = fpga_mgr_parse_header_mapped(mgr, info, buf, count);
+	if (ret)
+		return ret;
+
+	ret = fpga_mgr_write_init_buf(mgr, info, buf, count);
+	if (ret)
+		return ret;
+
+	if (mgr->mops->skip_header) {
+		buf += info->header_size;
+		count -= info->header_size;
+	}
+
+	if (info->data_size)
+		count = info->data_size;
+
+	/*
+	 * Write the FPGA image to the FPGA.
+	 */
+	mgr->state = FPGA_MGR_STATE_WRITE;
+	ret = fpga_mgr_write(mgr, buf, count);
+	if (ret) {
+		dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
+		mgr->state = FPGA_MGR_STATE_WRITE_ERR;
+		return ret;
+	}
+
+	return fpga_mgr_write_complete(mgr, info);
+}
+
+/**
+ * fpga_mgr_buf_load - load fpga from image in buffer
+ * @mgr:	fpga manager
+ * @info:	fpga image info
+ * @buf:	buffer contain fpga image
+ * @count:	byte count of buf
+ *
+ * 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.  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.
+ */
+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;
+	const void *p;
+	int nr_pages;
+	int index;
+	int rc;
+
+	/*
+	 * This is just a fast path if the caller has already created a
+	 * contiguous kernel buffer and the driver doesn't require SG, non-SG
+	 * drivers will still work on the slow path.
+	 */
+	if (mgr->mops->write)
+		return fpga_mgr_buf_load_mapped(mgr, info, buf, count);
+
+	/*
+	 * Convert the linear kernel pointer into a sg_table of pages for use
+	 * by the driver.
+	 */
+	nr_pages = DIV_ROUND_UP((unsigned long)buf + count, PAGE_SIZE) -
+		   (unsigned long)buf / PAGE_SIZE;
+	pages = kmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
+	if (!pages)
+		return -ENOMEM;
+
+	p = buf - offset_in_page(buf);
+	for (index = 0; index < nr_pages; index++) {
+		if (is_vmalloc_addr(p))
+			pages[index] = vmalloc_to_page(p);
+		else
+			pages[index] = kmap_to_page((void *)p);
+		if (!pages[index]) {
+			kfree(pages);
+			return -EFAULT;
+		}
+		p += PAGE_SIZE;
+	}
+
+	/*
+	 * The temporary pages list is used to code share the merging algorithm
+	 * in sg_alloc_table_from_pages
+	 */
+	rc = sg_alloc_table_from_pages(&sgt, pages, index, offset_in_page(buf),
+				       count, GFP_KERNEL);
+	kfree(pages);
+	if (rc)
+		return rc;
+
+	rc = fpga_mgr_buf_load_sg(mgr, info, &sgt);
+	sg_free_table(&sgt);
+
+	return rc;
+}
+
+/**
+ * fpga_mgr_firmware_load - request firmware and load to fpga
+ * @mgr:	fpga manager
+ * @info:	fpga image specific information
+ * @image_name:	name of image file on the firmware search path
+ *
+ * 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.  This code assumes the caller got the mgr pointer
+ * from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is not an error
+ * code.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+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;
+	int ret;
+
+	dev_info(dev, "writing %s to %s\n", image_name, mgr->name);
+
+	mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ;
+
+	ret = request_firmware(&fw, image_name, dev);
+	if (ret) {
+		mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ_ERR;
+		dev_err(dev, "Error requesting firmware %s\n", image_name);
+		return ret;
+	}
+
+	ret = fpga_mgr_buf_load(mgr, info, fw->data, fw->size);
+
+	release_firmware(fw);
+
+	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)
+{
+	info->header_size = mgr->mops->initial_header_size;
+
+	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",
+	[FPGA_MGR_STATE_POWER_OFF] =		"power off",
+	[FPGA_MGR_STATE_POWER_UP] =		"power up",
+	[FPGA_MGR_STATE_RESET] =		"reset",
+
+	/* requesting FPGA image from firmware */
+	[FPGA_MGR_STATE_FIRMWARE_REQ] =		"firmware request",
+	[FPGA_MGR_STATE_FIRMWARE_REQ_ERR] =	"firmware request error",
+
+	/* Parse FPGA image header */
+	[FPGA_MGR_STATE_PARSE_HEADER] =		"parse header",
+	[FPGA_MGR_STATE_PARSE_HEADER_ERR] =	"parse header error",
+
+	/* Preparing FPGA to receive image */
+	[FPGA_MGR_STATE_WRITE_INIT] =		"write init",
+	[FPGA_MGR_STATE_WRITE_INIT_ERR] =	"write init error",
+
+	/* Writing image to FPGA */
+	[FPGA_MGR_STATE_WRITE] =		"write",
+	[FPGA_MGR_STATE_WRITE_ERR] =		"write error",
+
+	/* Finishing configuration after image has been written */
+	[FPGA_MGR_STATE_WRITE_COMPLETE] =	"write complete",
+	[FPGA_MGR_STATE_WRITE_COMPLETE_ERR] =	"write complete error",
+
+	/* FPGA reports to be in normal operating mode */
+	[FPGA_MGR_STATE_OPERATING] =		"operating",
+};
+
+static ssize_t name_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct fpga_manager *mgr = to_fpga_manager(dev);
+
+	return sprintf(buf, "%s\n", mgr->name);
+}
+
+static ssize_t state_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct fpga_manager *mgr = to_fpga_manager(dev);
+
+	return sprintf(buf, "%s\n", state_str[mgr->state]);
+}
+
+static ssize_t status_show(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct fpga_manager *mgr = to_fpga_manager(dev);
+	u64 status;
+	int len = 0;
+
+	status = fpga_mgr_status(mgr);
+
+	if (status & FPGA_MGR_STATUS_OPERATION_ERR)
+		len += sprintf(buf + len, "reconfig operation error\n");
+	if (status & FPGA_MGR_STATUS_CRC_ERR)
+		len += sprintf(buf + len, "reconfig CRC error\n");
+	if (status & FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR)
+		len += sprintf(buf + len, "reconfig incompatible image\n");
+	if (status & FPGA_MGR_STATUS_IP_PROTOCOL_ERR)
+		len += sprintf(buf + len, "reconfig IP protocol error\n");
+	if (status & FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR)
+		len += sprintf(buf + len, "reconfig fifo overflow error\n");
+
+	return len;
+}
+
+static DEVICE_ATTR_RO(name);
+static DEVICE_ATTR_RO(state);
+static DEVICE_ATTR_RO(status);
+
+static struct attribute *fpga_mgr_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_state.attr,
+	&dev_attr_status.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(fpga_mgr);
+
+static struct fpga_manager *__fpga_mgr_get(struct device *dev)
+{
+	struct fpga_manager *mgr;
+
+	mgr = to_fpga_manager(dev);
+
+	if (!try_module_get(dev->parent->driver->owner))
+		goto err_dev;
+
+	return mgr;
+
+err_dev:
+	put_device(dev);
+	return ERR_PTR(-ENODEV);
+}
+
+static int fpga_mgr_dev_match(struct device *dev, const void *data)
+{
+	return dev->parent == data;
+}
+
+/**
+ * fpga_mgr_get - Given a device, get a reference to an fpga mgr.
+ * @dev:	parent device that fpga mgr was registered with
+ *
+ * Return: fpga manager struct or IS_ERR() condition containing error code.
+ */
+struct fpga_manager *fpga_mgr_get(struct device *dev)
+{
+	struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev,
+						   fpga_mgr_dev_match);
+	if (!mgr_dev)
+		return ERR_PTR(-ENODEV);
+
+	return __fpga_mgr_get(mgr_dev);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_get);
+
+/**
+ * of_fpga_mgr_get - Given a device node, get a reference to an fpga mgr.
+ *
+ * @node:	device node
+ *
+ * Return: fpga manager struct or IS_ERR() condition containing error code.
+ */
+struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
+{
+	struct device *dev;
+
+	dev = class_find_device_by_of_node(fpga_mgr_class, node);
+	if (!dev)
+		return ERR_PTR(-ENODEV);
+
+	return __fpga_mgr_get(dev);
+}
+EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
+
+/**
+ * fpga_mgr_put - release a reference to an fpga manager
+ * @mgr:	fpga manager structure
+ */
+void fpga_mgr_put(struct fpga_manager *mgr)
+{
+	module_put(mgr->dev.parent->driver->owner);
+	put_device(&mgr->dev);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_put);
+
+/**
+ * fpga_mgr_lock - Lock FPGA manager for exclusive use
+ * @mgr:	fpga manager
+ *
+ * Given a pointer to FPGA Manager (from fpga_mgr_get() or
+ * 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
+ */
+int fpga_mgr_lock(struct fpga_manager *mgr)
+{
+	if (!mutex_trylock(&mgr->ref_mutex)) {
+		dev_err(&mgr->dev, "FPGA manager is in use.\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_lock);
+
+/**
+ * fpga_mgr_unlock - Unlock FPGA manager after done programming
+ * @mgr:	fpga manager
+ */
+void fpga_mgr_unlock(struct fpga_manager *mgr)
+{
+	mutex_unlock(&mgr->ref_mutex);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
+
+/**
+ * fpga_mgr_register_full - create and register an FPGA Manager device
+ * @parent:	fpga manager device from pdev
+ * @info:	parameters for fpga manager
+ *
+ * The caller of this function is responsible for calling fpga_mgr_unregister().
+ * Using devm_fpga_mgr_register_full() instead is recommended.
+ *
+ * Return: pointer to struct fpga_manager pointer or ERR_PTR()
+ */
+struct fpga_manager *
+fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
+{
+	const struct fpga_manager_ops *mops = info->mops;
+	struct fpga_manager *mgr;
+	int id, ret;
+
+	if (!mops) {
+		dev_err(parent, "Attempt to register without fpga_manager_ops\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (!info->name || !strlen(info->name)) {
+		dev_err(parent, "Attempt to register with no name!\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+	if (!mgr)
+		return ERR_PTR(-ENOMEM);
+
+	id = ida_alloc(&fpga_mgr_ida, GFP_KERNEL);
+	if (id < 0) {
+		ret = id;
+		goto error_kfree;
+	}
+
+	mutex_init(&mgr->ref_mutex);
+
+	mgr->name = info->name;
+	mgr->mops = info->mops;
+	mgr->priv = info->priv;
+	mgr->compat_id = info->compat_id;
+
+	mgr->dev.class = fpga_mgr_class;
+	mgr->dev.groups = mops->groups;
+	mgr->dev.parent = parent;
+	mgr->dev.of_node = parent->of_node;
+	mgr->dev.id = id;
+
+	ret = dev_set_name(&mgr->dev, "fpga%d", id);
+	if (ret)
+		goto error_device;
+
+	/*
+	 * 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 = fpga_mgr_state(mgr);
+
+	ret = device_register(&mgr->dev);
+	if (ret) {
+		put_device(&mgr->dev);
+		return ERR_PTR(ret);
+	}
+
+	return mgr;
+
+error_device:
+	ida_free(&fpga_mgr_ida, id);
+error_kfree:
+	kfree(mgr);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_register_full);
+
+/**
+ * fpga_mgr_register - create and register an FPGA Manager device
+ * @parent:	fpga manager device from pdev
+ * @name:	fpga manager name
+ * @mops:	pointer to structure of fpga manager ops
+ * @priv:	fpga manager private data
+ *
+ * The caller of this function is responsible for calling fpga_mgr_unregister().
+ * Using devm_fpga_mgr_register() instead is recommended. This simple
+ * version of the register function should be sufficient for most users. The
+ * fpga_mgr_register_full() function is available for users that need to pass
+ * additional, optional parameters.
+ *
+ * Return: pointer to struct fpga_manager pointer or ERR_PTR()
+ */
+struct fpga_manager *
+fpga_mgr_register(struct device *parent, const char *name,
+		  const struct fpga_manager_ops *mops, void *priv)
+{
+	struct fpga_manager_info info = { 0 };
+
+	info.name = name;
+	info.mops = mops;
+	info.priv = priv;
+
+	return fpga_mgr_register_full(parent, &info);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_register);
+
+/**
+ * fpga_mgr_unregister - unregister an FPGA manager
+ * @mgr: fpga manager struct
+ *
+ * This function is intended for use in an FPGA manager driver's remove function.
+ */
+void fpga_mgr_unregister(struct fpga_manager *mgr)
+{
+	dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
+
+	/*
+	 * If the low level driver provides a method for putting fpga into
+	 * a desired state upon unregister, do it.
+	 */
+	fpga_mgr_fpga_remove(mgr);
+
+	device_unregister(&mgr->dev);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
+
+static void devm_fpga_mgr_unregister(struct device *dev, void *res)
+{
+	struct fpga_mgr_devres *dr = res;
+
+	fpga_mgr_unregister(dr->mgr);
+}
+
+/**
+ * devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register()
+ * @parent:	fpga manager device from pdev
+ * @info:	parameters for fpga manager
+ *
+ * Return:  fpga manager pointer on success, negative error code otherwise.
+ *
+ * This is the devres variant of fpga_mgr_register_full() for which the unregister
+ * function will be called automatically when the managing device is detached.
+ */
+struct fpga_manager *
+devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
+{
+	struct fpga_mgr_devres *dr;
+	struct fpga_manager *mgr;
+
+	dr = devres_alloc(devm_fpga_mgr_unregister, sizeof(*dr), GFP_KERNEL);
+	if (!dr)
+		return ERR_PTR(-ENOMEM);
+
+	mgr = fpga_mgr_register_full(parent, info);
+	if (IS_ERR(mgr)) {
+		devres_free(dr);
+		return mgr;
+	}
+
+	dr->mgr = mgr;
+	devres_add(parent, dr);
+
+	return mgr;
+}
+EXPORT_SYMBOL_GPL(devm_fpga_mgr_register_full);
+
+/**
+ * devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
+ * @parent:	fpga manager device from pdev
+ * @name:	fpga manager name
+ * @mops:	pointer to structure of fpga manager ops
+ * @priv:	fpga manager private data
+ *
+ * Return:  fpga manager pointer on success, negative error code otherwise.
+ *
+ * This is the devres variant of fpga_mgr_register() for which the
+ * unregister function will be called automatically when the managing
+ * device is detached.
+ */
+struct fpga_manager *
+devm_fpga_mgr_register(struct device *parent, const char *name,
+		       const struct fpga_manager_ops *mops, void *priv)
+{
+	struct fpga_manager_info info = { 0 };
+
+	info.name = name;
+	info.mops = mops;
+	info.priv = priv;
+
+	return devm_fpga_mgr_register_full(parent, &info);
+}
+EXPORT_SYMBOL_GPL(devm_fpga_mgr_register);
+
+static void fpga_mgr_dev_release(struct device *dev)
+{
+	struct fpga_manager *mgr = to_fpga_manager(dev);
+
+	ida_free(&fpga_mgr_ida, mgr->dev.id);
+	kfree(mgr);
+}
+
+static int __init fpga_mgr_class_init(void)
+{
+	pr_info("FPGA manager framework\n");
+
+	fpga_mgr_class = class_create(THIS_MODULE, "fpga_manager");
+	if (IS_ERR(fpga_mgr_class))
+		return PTR_ERR(fpga_mgr_class);
+
+	fpga_mgr_class->dev_groups = fpga_mgr_groups;
+	fpga_mgr_class->dev_release = fpga_mgr_dev_release;
+
+	return 0;
+}
+
+static void __exit fpga_mgr_class_exit(void)
+{
+	class_destroy(fpga_mgr_class);
+	ida_destroy(&fpga_mgr_ida);
+}
+
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
+MODULE_DESCRIPTION("FPGA manager framework");
+MODULE_LICENSE("GPL v2");
+
+subsys_initcall(fpga_mgr_class_init);
+module_exit(fpga_mgr_class_exit);