drivers/mtd/maps/pismo.c - kernel/bruno - Git at Google

 /*
  * PISMO memory driver - http://www.pismoworld.org/
  *
  * For ARM Realview and Versatile platforms
  *
  * 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.
  */
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/slab.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
 #include <linux/mtd/physmap.h>
 #include <linux/mtd/plat-ram.h>
 #include <linux/mtd/pismo.h>

 #define PISMO_NUM_CS	5

 struct pismo_cs_block {
 	u8	type;
 	u8	width;
 	__le16	access;
 	__le32	size;
 	u32	reserved[2];
 	char	device[32];
 } __packed;

 struct pismo_eeprom {
 	struct pismo_cs_block cs[PISMO_NUM_CS];
 	char	board[15];
 	u8	sum;
 } __packed;

 struct pismo_mem {
 	phys_addr_t base;
 	u32	size;
 	u16	access;
 	u8	width;
 	u8	type;
 };

 struct pismo_data {
 	struct i2c_client	*client;
 	void			(*vpp)(void *, int);
 	void			*vpp_data;
 	struct platform_device	*dev[PISMO_NUM_CS];
 };

 static void pismo_set_vpp(struct platform_device *pdev, int on)
 {
 	struct i2c_client *client = to_i2c_client(pdev->dev.parent);
 	struct pismo_data *pismo = i2c_get_clientdata(client);

 	pismo->vpp(pismo->vpp_data, on);
 }

 static unsigned int pismo_width_to_bytes(unsigned int width)
 {
 	width &= 15;
 	if (width > 2)
 		return 0;
 	return 1 << width;
 }

 static int pismo_eeprom_read(struct i2c_client *client, void *buf, u8 addr,
 			     size_t size)
 {
 	int ret;
 	struct i2c_msg msg[] = {
 		{
 			.addr = client->addr,
 			.len = sizeof(addr),
 			.buf = &addr,
 		}, {
 			.addr = client->addr,
 			.flags = I2C_M_RD,
 			.len = size,
 			.buf = buf,
 		},
 	};

 	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));

 	return ret == ARRAY_SIZE(msg) ? size : -EIO;
 }

 static int pismo_add_device(struct pismo_data *pismo, int i,
 			    struct pismo_mem *region, const char *name,
 			    void *pdata, size_t psize)
 {
 	struct platform_device *dev;
 	struct resource res = { };
 	phys_addr_t base = region->base;
 	int ret;

 	if (base == ~0)
 		return -ENXIO;

 	res.start = base;
 	res.end = base + region->size - 1;
 	res.flags = IORESOURCE_MEM;

 	dev = platform_device_alloc(name, i);
 	if (!dev)
 		return -ENOMEM;
 	dev->dev.parent = &pismo->client->dev;

 	do {
 		ret = platform_device_add_resources(dev, &res, 1);
 		if (ret)
 			break;

 		ret = platform_device_add_data(dev, pdata, psize);
 		if (ret)
 			break;

 		ret = platform_device_add(dev);
 		if (ret)
 			break;

 		pismo->dev[i] = dev;
 		return 0;
 	} while (0);

 	platform_device_put(dev);
 	return ret;
 }

 static int pismo_add_nor(struct pismo_data *pismo, int i,
 			 struct pismo_mem *region)
 {
 	struct physmap_flash_data data = {
 		.width = region->width,
 	};

 	if (pismo->vpp)
 		data.set_vpp = pismo_set_vpp;

 	return pismo_add_device(pismo, i, region, "physmap-flash",
 		&data, sizeof(data));
 }

 static int pismo_add_sram(struct pismo_data *pismo, int i,
 			  struct pismo_mem *region)
 {
 	struct platdata_mtd_ram data = {
 		.bankwidth = region->width,
 	};

 	return pismo_add_device(pismo, i, region, "mtd-ram",
 		&data, sizeof(data));
 }

 static void pismo_add_one(struct pismo_data *pismo, int i,
 			  const struct pismo_cs_block *cs, phys_addr_t base)
 {
 	struct device *dev = &pismo->client->dev;
 	struct pismo_mem region;

 	region.base = base;
 	region.type = cs->type;
 	region.width = pismo_width_to_bytes(cs->width);
 	region.access = le16_to_cpu(cs->access);
 	region.size = le32_to_cpu(cs->size);

 	if (region.width == 0) {
 		dev_err(dev, "cs%u: bad width: %02x, ignoring\n", i, cs->width);
 		return;
 	}

 	/*
 	 * FIXME: may need to the platforms memory controller here, but at
 	 * the moment we assume that it has already been correctly setup.
 	 * The memory controller can also tell us the base address as well.
 	 */

 	dev_info(dev, "cs%u: %.32s: type %02x access %u00ps size %uK\n",
 		i, cs->device, region.type, region.access, region.size / 1024);

 	switch (region.type) {
 	case 0:
 		break;
 	case 1:
 		/* static DOC */
 		break;
 	case 2:
 		/* static NOR */
 		pismo_add_nor(pismo, i, &region);
 		break;
 	case 3:
 		/* static RAM */
 		pismo_add_sram(pismo, i, &region);
 		break;
 	}
 }

 static int pismo_remove(struct i2c_client *client)
 {
 	struct pismo_data *pismo = i2c_get_clientdata(client);
 	int i;

 	for (i = 0; i < ARRAY_SIZE(pismo->dev); i++)
 		platform_device_unregister(pismo->dev[i]);

 	kfree(pismo);

 	return 0;
 }

 static int pismo_probe(struct i2c_client *client,
 		       const struct i2c_device_id *id)
 {
 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 	struct pismo_pdata *pdata = client->dev.platform_data;
 	struct pismo_eeprom eeprom;
 	struct pismo_data *pismo;
 	int ret, i;

 	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
 		dev_err(&client->dev, "functionality mismatch\n");
 		return -EIO;
 	}

 	pismo = kzalloc(sizeof(*pismo), GFP_KERNEL);
 	if (!pismo)
 		return -ENOMEM;

 	pismo->client = client;
 	if (pdata) {
 		pismo->vpp = pdata->set_vpp;
 		pismo->vpp_data = pdata->vpp_data;
 	}
 	i2c_set_clientdata(client, pismo);

 	ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
 	if (ret < 0) {
 		dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
 		goto exit_free;
 	}

 	dev_info(&client->dev, "%.15s board found\n", eeprom.board);

 	for (i = 0; i < ARRAY_SIZE(eeprom.cs); i++)
 		if (eeprom.cs[i].type != 0xff)
 			pismo_add_one(pismo, i, &eeprom.cs[i],
 				      pdata->cs_addrs[i]);

 	return 0;

  exit_free:
 	kfree(pismo);
 	return ret;
 }

 static const struct i2c_device_id pismo_id[] = {
 	{ "pismo" },
 	{ },
 };
 MODULE_DEVICE_TABLE(i2c, pismo_id);

 static struct i2c_driver pismo_driver = {
 	.driver	= {
 		.name	= "pismo",
 		.owner	= THIS_MODULE,
 	},
 	.probe		= pismo_probe,
 	.remove		= pismo_remove,
 	.id_table	= pismo_id,
 };

 static int __init pismo_init(void)
 {
 	BUILD_BUG_ON(sizeof(struct pismo_cs_block) != 48);
 	BUILD_BUG_ON(sizeof(struct pismo_eeprom) != 256);

 	return i2c_add_driver(&pismo_driver);
 }
 module_init(pismo_init);

 static void __exit pismo_exit(void)
 {
 	i2c_del_driver(&pismo_driver);
 }
 module_exit(pismo_exit);

 MODULE_AUTHOR("Russell King <linux@arm.linux.org.uk>");
 MODULE_DESCRIPTION("PISMO memory driver");
 MODULE_LICENSE("GPL");
	/*
	* PISMO memory driver - http://www.pismoworld.org/
	*
	* For ARM Realview and Versatile platforms
	*
	* 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.
	*/
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/i2c.h>
	#include <linux/slab.h>
	#include <linux/platform_device.h>
	#include <linux/spinlock.h>
	#include <linux/mutex.h>
	#include <linux/mtd/physmap.h>
	#include <linux/mtd/plat-ram.h>
	#include <linux/mtd/pismo.h>

	#define PISMO_NUM_CS 5

	struct pismo_cs_block {
	u8 type;
	u8 width;
	__le16 access;
	__le32 size;
	u32 reserved[2];
	char device[32];
	} __packed;

	struct pismo_eeprom {
	struct pismo_cs_block cs[PISMO_NUM_CS];
	char board[15];
	u8 sum;
	} __packed;

	struct pismo_mem {
	phys_addr_t base;
	u32 size;
	u16 access;
	u8 width;
	u8 type;
	};

	struct pismo_data {
	struct i2c_client *client;
	void (vpp)(void , int);
	void *vpp_data;
	struct platform_device *dev[PISMO_NUM_CS];
	};

	static void pismo_set_vpp(struct platform_device *pdev, int on)
	{
	struct i2c_client *client = to_i2c_client(pdev->dev.parent);
	struct pismo_data *pismo = i2c_get_clientdata(client);

	pismo->vpp(pismo->vpp_data, on);
	}

	static unsigned int pismo_width_to_bytes(unsigned int width)
	{
	width &= 15;
	if (width > 2)
	return 0;
	return 1 << width;
	}

	static int pismo_eeprom_read(struct i2c_client client, void buf, u8 addr,
	size_t size)
	{
	int ret;
	struct i2c_msg msg[] = {
	{
	.addr = client->addr,
	.len = sizeof(addr),
	.buf = &addr,
	}, {
	.addr = client->addr,
	.flags = I2C_M_RD,
	.len = size,
	.buf = buf,
	},
	};

	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));

	return ret == ARRAY_SIZE(msg) ? size : -EIO;
	}

	static int pismo_add_device(struct pismo_data *pismo, int i,
	struct pismo_mem region, const char name,
	void *pdata, size_t psize)
	{
	struct platform_device *dev;
	struct resource res = { };
	phys_addr_t base = region->base;
	int ret;

	if (base == ~0)
	return -ENXIO;

	res.start = base;
	res.end = base + region->size - 1;
	res.flags = IORESOURCE_MEM;

	dev = platform_device_alloc(name, i);
	if (!dev)
	return -ENOMEM;
	dev->dev.parent = &pismo->client->dev;

	do {
	ret = platform_device_add_resources(dev, &res, 1);
	if (ret)
	break;

	ret = platform_device_add_data(dev, pdata, psize);
	if (ret)
	break;

	ret = platform_device_add(dev);
	if (ret)
	break;

	pismo->dev[i] = dev;
	return 0;
	} while (0);

	platform_device_put(dev);
	return ret;
	}

	static int pismo_add_nor(struct pismo_data *pismo, int i,
	struct pismo_mem *region)
	{
	struct physmap_flash_data data = {
	.width = region->width,
	};

	if (pismo->vpp)
	data.set_vpp = pismo_set_vpp;

	return pismo_add_device(pismo, i, region, "physmap-flash",
	&data, sizeof(data));
	}

	static int pismo_add_sram(struct pismo_data *pismo, int i,
	struct pismo_mem *region)
	{
	struct platdata_mtd_ram data = {
	.bankwidth = region->width,
	};

	return pismo_add_device(pismo, i, region, "mtd-ram",
	&data, sizeof(data));
	}

	static void pismo_add_one(struct pismo_data *pismo, int i,
	const struct pismo_cs_block *cs, phys_addr_t base)
	{
	struct device *dev = &pismo->client->dev;
	struct pismo_mem region;

	region.base = base;
	region.type = cs->type;
	region.width = pismo_width_to_bytes(cs->width);
	region.access = le16_to_cpu(cs->access);
	region.size = le32_to_cpu(cs->size);

	if (region.width == 0) {
	dev_err(dev, "cs%u: bad width: %02x, ignoring\n", i, cs->width);
	return;
	}

	/*
	* FIXME: may need to the platforms memory controller here, but at
	* the moment we assume that it has already been correctly setup.
	* The memory controller can also tell us the base address as well.
	*/

	dev_info(dev, "cs%u: %.32s: type %02x access %u00ps size %uK\n",
	i, cs->device, region.type, region.access, region.size / 1024);

	switch (region.type) {
	case 0:
	break;
	case 1:
	/* static DOC */
	break;
	case 2:
	/* static NOR */
	pismo_add_nor(pismo, i, &region);
	break;
	case 3:
	/* static RAM */
	pismo_add_sram(pismo, i, &region);
	break;
	}
	}

	static int pismo_remove(struct i2c_client *client)
	{
	struct pismo_data *pismo = i2c_get_clientdata(client);
	int i;

	for (i = 0; i < ARRAY_SIZE(pismo->dev); i++)
	platform_device_unregister(pismo->dev[i]);

	kfree(pismo);

	return 0;
	}

	static int pismo_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	struct pismo_pdata *pdata = client->dev.platform_data;
	struct pismo_eeprom eeprom;
	struct pismo_data *pismo;
	int ret, i;

	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
	dev_err(&client->dev, "functionality mismatch\n");
	return -EIO;
	}

	pismo = kzalloc(sizeof(*pismo), GFP_KERNEL);
	if (!pismo)
	return -ENOMEM;

	pismo->client = client;
	if (pdata) {
	pismo->vpp = pdata->set_vpp;
	pismo->vpp_data = pdata->vpp_data;
	}
	i2c_set_clientdata(client, pismo);

	ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
	if (ret < 0) {
	dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
	goto exit_free;
	}

	dev_info(&client->dev, "%.15s board found\n", eeprom.board);

	for (i = 0; i < ARRAY_SIZE(eeprom.cs); i++)
	if (eeprom.cs[i].type != 0xff)
	pismo_add_one(pismo, i, &eeprom.cs[i],
	pdata->cs_addrs[i]);

	return 0;

	exit_free:
	kfree(pismo);
	return ret;
	}

	static const struct i2c_device_id pismo_id[] = {
	{ "pismo" },
	{ },
	};
	MODULE_DEVICE_TABLE(i2c, pismo_id);

	static struct i2c_driver pismo_driver = {
	.driver = {
	.name = "pismo",
	.owner = THIS_MODULE,
	},
	.probe = pismo_probe,
	.remove = pismo_remove,
	.id_table = pismo_id,
	};

	static int __init pismo_init(void)
	{
	BUILD_BUG_ON(sizeof(struct pismo_cs_block) != 48);
	BUILD_BUG_ON(sizeof(struct pismo_eeprom) != 256);

	return i2c_add_driver(&pismo_driver);
	}
	module_init(pismo_init);

	static void __exit pismo_exit(void)
	{
	i2c_del_driver(&pismo_driver);
	}
	module_exit(pismo_exit);

	MODULE_AUTHOR("Russell King <linux@arm.linux.org.uk>");
	MODULE_DESCRIPTION("PISMO memory driver");
	MODULE_LICENSE("GPL");