fpga: mgr: separate getting/locking FPGA manager (ebf877a5) · Commits · 戴 / test

Documentation/fpga/fpga-mgr.txt

+26 −9

Original line number	Diff line number	Diff line
		@@ -48,8 +48,20 @@ To get/put a reference to a FPGA manager:
		struct fpga_manager fpga_mgr_get(struct device dev);
		void fpga_mgr_put(struct fpga_manager *mgr);

		Given a DT node or device, get an exclusive reference to a FPGA manager.
		fpga_mgr_put releases the reference.
		Given a DT node or device, get a reference to a FPGA manager. This pointer
		can be saved until you are ready to program the FPGA. fpga_mgr_put releases
		the reference.


		To get exclusive control of a FPGA manager:
		-------------------------------------------

		int fpga_mgr_lock(struct fpga_manager *mgr);
		void fpga_mgr_unlock(struct fpga_manager *mgr);

		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.


		To register or unregister the low level FPGA-specific driver:
		@@ -67,13 +79,21 @@ device."

		How to write an image buffer to a supported FPGA
		================================================
		/* Include to get the API */
		#include <linux/fpga/fpga-mgr.h>

		struct fpga_manager *mgr;
		struct fpga_image_info *info;
		int ret;

		/*
		* Get a reference to FPGA manager. The manager is not locked, so you can
		* hold onto this reference without it preventing programming.
		*
		* This example uses the device node of the manager. Alternatively, use
		* fpga_mgr_get(dev) instead if you have the device.
		*/
		mgr = of_fpga_mgr_get(mgr_node);

		/* struct with information about the FPGA image to program. */
		info = fpga_image_info_alloc(dev);

		@@ -99,17 +119,14 @@ if (image is in a scatter gather table) {

		}

		/*
		* Get a reference to FPGA manager. This example uses the device node of the
		* manager. You could use fpga_mgr_get() instead if you have the device instead
		* of the device node.
		*/
		mgr = of_fpga_mgr_get(mgr_node);
		/* Get exclusive control of FPGA manager */
		ret = fpga_mgr_lock(mgr);

		/* Load the buffer to the FPGA */
		ret = fpga_mgr_buf_load(mgr, &info, buf, count);

		/* Release the FPGA manager */
		fpga_mgr_unlock(mgr);
		fpga_mgr_put(mgr);

		/* Deallocate the image info if you're done with it */

drivers/fpga/fpga-mgr.c

+36 −16

Original line number	Diff line number	Diff line
		@@ -410,28 +410,19 @@ ATTRIBUTE_GROUPS(fpga_mgr);
		static struct fpga_manager __fpga_mgr_get(struct device dev)
		{
		struct fpga_manager *mgr;
		int ret = -ENODEV;

		mgr = to_fpga_manager(dev);
		if (!mgr)
		goto err_dev;

		/* Get exclusive use of fpga manager */
		if (!mutex_trylock(&mgr->ref_mutex)) {
		ret = -EBUSY;
		goto err_dev;
		}

		if (!try_module_get(dev->parent->driver->owner))
		goto err_ll_mod;
		goto err_dev;

		return mgr;

		err_ll_mod:
		mutex_unlock(&mgr->ref_mutex);
		err_dev:
		put_device(dev);
		return ERR_PTR(ret);
		return ERR_PTR(-ENODEV);
		}

		static int fpga_mgr_dev_match(struct device dev, const void data)
		@@ -440,10 +431,10 @@ static int fpga_mgr_dev_match(struct device dev, const void data)
		}

		/**
		* fpga_mgr_get - get an exclusive reference to a fpga mgr
		* fpga_mgr_get - get a reference to a fpga mgr
		* @dev: parent device that fpga mgr was registered with
		*
		* Given a device, get an exclusive reference to a fpga mgr.
		* Given a device, get a reference to a fpga mgr.
		*
		* Return: fpga manager struct or IS_ERR() condition containing error code.
		*/
		@@ -464,10 +455,10 @@ static int fpga_mgr_of_node_match(struct device dev, const void data)
		}

		/**
		* of_fpga_mgr_get - get an exclusive reference to a fpga mgr
		* of_fpga_mgr_get - get a reference to a fpga mgr
		* @node: device node
		*
		* Given a device node, get an exclusive reference to a fpga mgr.
		* Given a device node, get a reference to a fpga mgr.
		*
		* Return: fpga manager struct or IS_ERR() condition containing error code.
		*/
		@@ -491,11 +482,40 @@ EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
		void fpga_mgr_put(struct fpga_manager *mgr)
		{
		module_put(mgr->dev.parent->driver->owner);
		mutex_unlock(&mgr->ref_mutex);
		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.
		*
		* 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
		* @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 - register a low level fpga manager driver
		* @dev: fpga manager device from pdev

drivers/fpga/fpga-region.c

+12 −2

Original line number	Diff line number	Diff line
		@@ -125,7 +125,7 @@ static void fpga_region_put(struct fpga_region *region)
		}

		/**
		* fpga_region_get_manager - get exclusive reference for FPGA manager
		* fpga_region_get_manager - get reference for FPGA manager
		* @region: FPGA region
		*
		* Get FPGA Manager from "fpga-mgr" property or from ancestor region.
		@@ -233,6 +233,7 @@ static int fpga_region_get_bridges(struct fpga_region *region,
		static int fpga_region_program_fpga(struct fpga_region *region,
		struct device_node *overlay)
		{
		struct device *dev = &region->dev;
		struct fpga_manager *mgr;
		int ret;

		@@ -249,10 +250,16 @@ static int fpga_region_program_fpga(struct fpga_region *region,
		goto err_put_region;
		}

		ret = fpga_mgr_lock(mgr);
		if (ret) {
		dev_err(dev, "FPGA manager is busy\n");
		goto err_put_mgr;
		}

		ret = fpga_region_get_bridges(region, overlay);
		if (ret) {
		pr_err("failed to get fpga region bridges\n");
		goto err_put_mgr;
		goto err_unlock_mgr;
		}

		ret = fpga_bridges_disable(&region->bridge_list);
		@@ -273,6 +280,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
		goto err_put_br;
		}

		fpga_mgr_unlock(mgr);
		fpga_mgr_put(mgr);
		fpga_region_put(region);

		@@ -280,6 +288,8 @@ static int fpga_region_program_fpga(struct fpga_region *region,

		err_put_br:
		fpga_bridges_put(&region->bridge_list);
		err_unlock_mgr:
		fpga_mgr_unlock(mgr);
		err_put_mgr:
		fpga_mgr_put(mgr);
		err_put_region:

include/linux/fpga/fpga-mgr.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -155,6 +155,9 @@ void fpga_image_info_free(struct fpga_image_info *info);

		int fpga_mgr_load(struct fpga_manager mgr, struct fpga_image_info info);

		int fpga_mgr_lock(struct fpga_manager *mgr);
		void fpga_mgr_unlock(struct fpga_manager *mgr);

		struct fpga_manager of_fpga_mgr_get(struct device_node node);

		struct fpga_manager fpga_mgr_get(struct device dev);

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