drivers/mtd/maps/plat-ram.c - kernel/prism - Git at Google

 /* drivers/mtd/maps/plat-ram.c
  *
  * (c) 2004-2005 Simtec Electronics
  *	http://www.simtec.co.uk/products/SWLINUX/
  *	Ben Dooks <ben@simtec.co.uk>
  *
  * Generic platfrom device based RAM map
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that 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, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/ioport.h>
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/platform_device.h>

 #include <linux/mtd/mtd.h>
 #include <linux/mtd/map.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/plat-ram.h>

 #include <asm/io.h>

 /* private structure for each mtd platform ram device created */

 struct platram_info {
 	struct device		*dev;
 	struct mtd_info		*mtd;
 	struct map_info		 map;
 	struct mtd_partition	*partitions;
 	bool			free_partitions;
 	struct resource		*area;
 	struct platdata_mtd_ram	*pdata;
 };

 /* to_platram_info()
  *
  * device private data to struct platram_info conversion
 */

 static inline struct platram_info *to_platram_info(struct platform_device *dev)
 {
 	return (struct platram_info *)platform_get_drvdata(dev);
 }

 /* platram_setrw
  *
  * call the platform device's set rw/ro control
  *
  * to = 0 => read-only
  *    = 1 => read-write
 */

 static inline void platram_setrw(struct platram_info *info, int to)
 {
 	if (info->pdata == NULL)
 		return;

 	if (info->pdata->set_rw != NULL)
 		(info->pdata->set_rw)(info->dev, to);
 }

 /* platram_remove
  *
  * called to remove the device from the driver's control
 */

 static int platram_remove(struct platform_device *pdev)
 {
 	struct platram_info *info = to_platram_info(pdev);

 	platform_set_drvdata(pdev, NULL);

 	dev_dbg(&pdev->dev, "removing device\n");

 	if (info == NULL)
 		return 0;

 	if (info->mtd) {
 #ifdef CONFIG_MTD_PARTITIONS
 		if (info->partitions) {
 			del_mtd_partitions(info->mtd);
 			if (info->free_partitions)
 				kfree(info->partitions);
 		}
 #endif
 		del_mtd_device(info->mtd);
 		map_destroy(info->mtd);
 	}

 	/* ensure ram is left read-only */

 	platram_setrw(info, PLATRAM_RO);

 	/* release resources */

 	if (info->area) {
 		release_resource(info->area);
 		kfree(info->area);
 	}

 	if (info->map.virt != NULL)
 		iounmap(info->map.virt);

 	kfree(info);

 	return 0;
 }

 /* platram_probe
  *
  * called from device drive system when a device matching our
  * driver is found.
 */

 static int platram_probe(struct platform_device *pdev)
 {
 	struct platdata_mtd_ram	*pdata;
 	struct platram_info *info;
 	struct resource *res;
 	int err = 0;

 	dev_dbg(&pdev->dev, "probe entered\n");

 	if (pdev->dev.platform_data == NULL) {
 		dev_err(&pdev->dev, "no platform data supplied\n");
 		err = -ENOENT;
 		goto exit_error;
 	}

 	pdata = pdev->dev.platform_data;

 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (info == NULL) {
 		dev_err(&pdev->dev, "no memory for flash info\n");
 		err = -ENOMEM;
 		goto exit_error;
 	}

 	platform_set_drvdata(pdev, info);

 	info->dev = &pdev->dev;
 	info->pdata = pdata;

 	/* get the resource for the memory mapping */

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

 	if (res == NULL) {
 		dev_err(&pdev->dev, "no memory resource specified\n");
 		err = -ENOENT;
 		goto exit_free;
 	}

 	dev_dbg(&pdev->dev, "got platform resource %p (0x%llx)\n", res,
 		(unsigned long long)res->start);

 	/* setup map parameters */

 	info->map.phys = res->start;
 	info->map.size = resource_size(res);
 	info->map.name = pdata->mapname != NULL ?
 			(char *)pdata->mapname : (char *)pdev->name;
 	info->map.bankwidth = pdata->bankwidth;

 	/* register our usage of the memory area */

 	info->area = request_mem_region(res->start, info->map.size, pdev->name);
 	if (info->area == NULL) {
 		dev_err(&pdev->dev, "failed to request memory region\n");
 		err = -EIO;
 		goto exit_free;
 	}

 	/* remap the memory area */

 	info->map.virt = ioremap(res->start, info->map.size);
 	dev_dbg(&pdev->dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size);

 	if (info->map.virt == NULL) {
 		dev_err(&pdev->dev, "failed to ioremap() region\n");
 		err = -EIO;
 		goto exit_free;
 	}

 	simple_map_init(&info->map);

 	dev_dbg(&pdev->dev, "initialised map, probing for mtd\n");

 	/* probe for the right mtd map driver
 	 * supplied by the platform_data struct */

 	if (pdata->map_probes) {
 		const char **map_probes = pdata->map_probes;

 		for ( ; !info->mtd && *map_probes; map_probes++)
 			info->mtd = do_map_probe(*map_probes , &info->map);
 	}
 	/* fallback to map_ram */
 	else
 		info->mtd = do_map_probe("map_ram", &info->map);

 	if (info->mtd == NULL) {
 		dev_err(&pdev->dev, "failed to probe for map_ram\n");
 		err = -ENOMEM;
 		goto exit_free;
 	}

 	info->mtd->owner = THIS_MODULE;
 	info->mtd->dev.parent = &pdev->dev;

 	platram_setrw(info, PLATRAM_RW);

 	/* check to see if there are any available partitions, or wether
 	 * to add this device whole */

 #ifdef CONFIG_MTD_PARTITIONS
 	if (!pdata->nr_partitions) {
 		/* try to probe using the supplied probe type */
 		if (pdata->probes) {
 			err = parse_mtd_partitions(info->mtd, pdata->probes,
 					   &info->partitions, 0);
 			info->free_partitions = 1;
 			if (err > 0)
 				err = add_mtd_partitions(info->mtd,
 					info->partitions, err);
 		}
 	}
 	/* use the static mapping */
 	else
 		err = add_mtd_partitions(info->mtd, pdata->partitions,
 				pdata->nr_partitions);
 #endif /* CONFIG_MTD_PARTITIONS */

 	if (add_mtd_device(info->mtd)) {
 		dev_err(&pdev->dev, "add_mtd_device() failed\n");
 		err = -ENOMEM;
 	}

 	if (!err)
 		dev_info(&pdev->dev, "registered mtd device\n");

 	return err;

  exit_free:
 	platram_remove(pdev);
  exit_error:
 	return err;
 }

 /* device driver info */

 /* work with hotplug and coldplug */
 MODULE_ALIAS("platform:mtd-ram");

 static struct platform_driver platram_driver = {
 	.probe		= platram_probe,
 	.remove		= platram_remove,
 	.driver		= {
 		.name	= "mtd-ram",
 		.owner	= THIS_MODULE,
 	},
 };

 /* module init/exit */

 static int __init platram_init(void)
 {
 	printk("Generic platform RAM MTD, (c) 2004 Simtec Electronics\n");
 	return platform_driver_register(&platram_driver);
 }

 static void __exit platram_exit(void)
 {
 	platform_driver_unregister(&platram_driver);
 }

 module_init(platram_init);
 module_exit(platram_exit);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 MODULE_DESCRIPTION("MTD platform RAM map driver");
	/* drivers/mtd/maps/plat-ram.c
	*
	* (c) 2004-2005 Simtec Electronics
	* http://www.simtec.co.uk/products/SWLINUX/
	* Ben Dooks <ben@simtec.co.uk>
	*
	* Generic platfrom device based RAM map
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that 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, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/module.h>
	#include <linux/types.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/string.h>
	#include <linux/ioport.h>
	#include <linux/device.h>
	#include <linux/slab.h>
	#include <linux/platform_device.h>

	#include <linux/mtd/mtd.h>
	#include <linux/mtd/map.h>
	#include <linux/mtd/partitions.h>
	#include <linux/mtd/plat-ram.h>

	#include <asm/io.h>

	/* private structure for each mtd platform ram device created */

	struct platram_info {
	struct device *dev;
	struct mtd_info *mtd;
	struct map_info map;
	struct mtd_partition *partitions;
	bool free_partitions;
	struct resource *area;
	struct platdata_mtd_ram *pdata;
	};

	/* to_platram_info()
	*
	* device private data to struct platram_info conversion
	*/

	static inline struct platram_info to_platram_info(struct platform_device dev)
	{
	return (struct platram_info *)platform_get_drvdata(dev);
	}

	/* platram_setrw
	*
	* call the platform device's set rw/ro control
	*
	* to = 0 => read-only
	* = 1 => read-write
	*/

	static inline void platram_setrw(struct platram_info *info, int to)
	{
	if (info->pdata == NULL)
	return;

	if (info->pdata->set_rw != NULL)
	(info->pdata->set_rw)(info->dev, to);
	}

	/* platram_remove
	*
	* called to remove the device from the driver's control
	*/

	static int platram_remove(struct platform_device *pdev)
	{
	struct platram_info *info = to_platram_info(pdev);

	platform_set_drvdata(pdev, NULL);

	dev_dbg(&pdev->dev, "removing device\n");

	if (info == NULL)
	return 0;

	if (info->mtd) {
	#ifdef CONFIG_MTD_PARTITIONS
	if (info->partitions) {
	del_mtd_partitions(info->mtd);
	if (info->free_partitions)
	kfree(info->partitions);
	}
	#endif
	del_mtd_device(info->mtd);
	map_destroy(info->mtd);
	}

	/* ensure ram is left read-only */

	platram_setrw(info, PLATRAM_RO);

	/* release resources */

	if (info->area) {
	release_resource(info->area);
	kfree(info->area);
	}

	if (info->map.virt != NULL)
	iounmap(info->map.virt);

	kfree(info);

	return 0;
	}

	/* platram_probe
	*
	* called from device drive system when a device matching our
	* driver is found.
	*/

	static int platram_probe(struct platform_device *pdev)
	{
	struct platdata_mtd_ram *pdata;
	struct platram_info *info;
	struct resource *res;
	int err = 0;

	dev_dbg(&pdev->dev, "probe entered\n");

	if (pdev->dev.platform_data == NULL) {
	dev_err(&pdev->dev, "no platform data supplied\n");
	err = -ENOENT;
	goto exit_error;
	}

	pdata = pdev->dev.platform_data;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (info == NULL) {
	dev_err(&pdev->dev, "no memory for flash info\n");
	err = -ENOMEM;
	goto exit_error;
	}

	platform_set_drvdata(pdev, info);

	info->dev = &pdev->dev;
	info->pdata = pdata;

	/* get the resource for the memory mapping */

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (res == NULL) {
	dev_err(&pdev->dev, "no memory resource specified\n");
	err = -ENOENT;
	goto exit_free;
	}

	dev_dbg(&pdev->dev, "got platform resource %p (0x%llx)\n", res,
	(unsigned long long)res->start);

	/* setup map parameters */

	info->map.phys = res->start;
	info->map.size = resource_size(res);
	info->map.name = pdata->mapname != NULL ?
	(char )pdata->mapname : (char )pdev->name;
	info->map.bankwidth = pdata->bankwidth;

	/* register our usage of the memory area */

	info->area = request_mem_region(res->start, info->map.size, pdev->name);
	if (info->area == NULL) {
	dev_err(&pdev->dev, "failed to request memory region\n");
	err = -EIO;
	goto exit_free;
	}

	/* remap the memory area */

	info->map.virt = ioremap(res->start, info->map.size);
	dev_dbg(&pdev->dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size);

	if (info->map.virt == NULL) {
	dev_err(&pdev->dev, "failed to ioremap() region\n");
	err = -EIO;
	goto exit_free;
	}

	simple_map_init(&info->map);

	dev_dbg(&pdev->dev, "initialised map, probing for mtd\n");

	/* probe for the right mtd map driver
	* supplied by the platform_data struct */

	if (pdata->map_probes) {
	const char **map_probes = pdata->map_probes;

	for ( ; !info->mtd && *map_probes; map_probes++)
	info->mtd = do_map_probe(*map_probes , &info->map);
	}
	/* fallback to map_ram */
	else
	info->mtd = do_map_probe("map_ram", &info->map);

	if (info->mtd == NULL) {
	dev_err(&pdev->dev, "failed to probe for map_ram\n");
	err = -ENOMEM;
	goto exit_free;
	}

	info->mtd->owner = THIS_MODULE;
	info->mtd->dev.parent = &pdev->dev;

	platram_setrw(info, PLATRAM_RW);

	/* check to see if there are any available partitions, or wether
	* to add this device whole */

	#ifdef CONFIG_MTD_PARTITIONS
	if (!pdata->nr_partitions) {
	/* try to probe using the supplied probe type */
	if (pdata->probes) {
	err = parse_mtd_partitions(info->mtd, pdata->probes,
	&info->partitions, 0);
	info->free_partitions = 1;
	if (err > 0)
	err = add_mtd_partitions(info->mtd,
	info->partitions, err);
	}
	}
	/* use the static mapping */
	else
	err = add_mtd_partitions(info->mtd, pdata->partitions,
	pdata->nr_partitions);
	#endif /* CONFIG_MTD_PARTITIONS */

	if (add_mtd_device(info->mtd)) {
	dev_err(&pdev->dev, "add_mtd_device() failed\n");
	err = -ENOMEM;
	}

	if (!err)
	dev_info(&pdev->dev, "registered mtd device\n");

	return err;

	exit_free:
	platram_remove(pdev);
	exit_error:
	return err;
	}

	/* device driver info */

	/* work with hotplug and coldplug */
	MODULE_ALIAS("platform:mtd-ram");

	static struct platform_driver platram_driver = {
	.probe = platram_probe,
	.remove = platram_remove,
	.driver = {
	.name = "mtd-ram",
	.owner = THIS_MODULE,
	},
	};

	/* module init/exit */

	static int __init platram_init(void)
	{
	printk("Generic platform RAM MTD, (c) 2004 Simtec Electronics\n");
	return platform_driver_register(&platram_driver);
	}

	static void __exit platram_exit(void)
	{
	platform_driver_unregister(&platram_driver);
	}

	module_init(platram_init);
	module_exit(platram_exit);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	MODULE_DESCRIPTION("MTD platform RAM map driver");