[mirror_ubuntu-artful-kernel.git] / drivers / sbus / char / flash.c

/* $Id: flash.c,v 1.25 2001/12/21 04:56:16 davem Exp $
 * flash.c: Allow mmap access to the OBP Flash, for OBP updates.
 *
 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/mm.h>

#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/sbus.h>
#include <asm/ebus.h>
#include <asm/upa.h>

static DEFINE_SPINLOCK(flash_lock);
static struct {
	unsigned long read_base;	/* Physical read address */
	unsigned long write_base;	/* Physical write address */
	unsigned long read_size;	/* Size of read area */
	unsigned long write_size;	/* Size of write area */
	unsigned long busy;		/* In use? */
} flash;

#define FLASH_MINOR	152

static int
flash_mmap(struct file *file, struct vm_area_struct *vma)
{
	unsigned long addr;
	unsigned long size;

	spin_lock(&flash_lock);
	if (flash.read_base == flash.write_base) {
		addr = flash.read_base;
		size = flash.read_size;
	} else {
		if ((vma->vm_flags & VM_READ) &&
		    (vma->vm_flags & VM_WRITE)) {
			spin_unlock(&flash_lock);
			return -EINVAL;
		}
		if (vma->vm_flags & VM_READ) {
			addr = flash.read_base;
			size = flash.read_size;
		} else if (vma->vm_flags & VM_WRITE) {
			addr = flash.write_base;
			size = flash.write_size;
		} else {
			spin_unlock(&flash_lock);
			return -ENXIO;
		}
	}
	spin_unlock(&flash_lock);

	if ((vma->vm_pgoff << PAGE_SHIFT) > size)
		return -ENXIO;
	addr = vma->vm_pgoff + (addr >> PAGE_SHIFT);

	if (vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT)) > size)
		size = vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT));

	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

	if (io_remap_pfn_range(vma, vma->vm_start, addr, size, vma->vm_page_prot))
		return -EAGAIN;
		
	return 0;
}

static long long
flash_llseek(struct file *file, long long offset, int origin)
{
	lock_kernel();
	switch (origin) {
		case 0:
			file->f_pos = offset;
			break;
		case 1:
			file->f_pos += offset;
			if (file->f_pos > flash.read_size)
				file->f_pos = flash.read_size;
			break;
		case 2:
			file->f_pos = flash.read_size;
			break;
		default:
			unlock_kernel();
			return -EINVAL;
	}
	unlock_kernel();
	return file->f_pos;
}

static ssize_t
flash_read(struct file * file, char __user * buf,
	   size_t count, loff_t *ppos)
{
	unsigned long p = file->f_pos;
	int i;
	
	if (count > flash.read_size - p)
		count = flash.read_size - p;

	for (i = 0; i < count; i++) {
		u8 data = upa_readb(flash.read_base + p + i);
		if (put_user(data, buf))
			return -EFAULT;
		buf++;
	}

	file->f_pos += count;
	return count;
}

static int
flash_open(struct inode *inode, struct file *file)
{
	lock_kernel();
	if (test_and_set_bit(0, (void *)&flash.busy) != 0) {
		unlock_kernel();
		return -EBUSY;
	}

	unlock_kernel();
	return 0;
}

static int
flash_release(struct inode *inode, struct file *file)
{
	spin_lock(&flash_lock);
	flash.busy = 0;
	spin_unlock(&flash_lock);

	return 0;
}

static const struct file_operations flash_fops = {
	/* no write to the Flash, use mmap
	 * and play flash dependent tricks.
	 */
	.owner =	THIS_MODULE,
	.llseek =	flash_llseek,
	.read =		flash_read,
	.mmap =		flash_mmap,
	.open =		flash_open,
	.release =	flash_release,
};

static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };

static int __init flash_init(void)
{
	struct sbus_bus *sbus;
	struct sbus_dev *sdev = NULL;
#ifdef CONFIG_PCI
	struct linux_ebus *ebus;
	struct linux_ebus_device *edev = NULL;
	struct linux_prom_registers regs[2];
	int len, nregs;
#endif
	int err;

	for_all_sbusdev(sdev, sbus) {
		if (!strcmp(sdev->prom_name, "flashprom")) {
			if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) {
				flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) |
					(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
				flash.read_size = sdev->reg_addrs[0].reg_size;
				flash.write_base = flash.read_base;
				flash.write_size = flash.read_size;
			} else {
				flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) |
					(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
				flash.read_size = sdev->reg_addrs[0].reg_size;
				flash.write_base = ((unsigned long)sdev->reg_addrs[1].phys_addr) |
					(((unsigned long)sdev->reg_addrs[1].which_io)<<32UL);
				flash.write_size = sdev->reg_addrs[1].reg_size;
			}
			flash.busy = 0;
			break;
		}
	}
	if (!sdev) {
#ifdef CONFIG_PCI
		const struct linux_prom_registers *ebus_regs;

		for_each_ebus(ebus) {
			for_each_ebusdev(edev, ebus) {
				if (!strcmp(edev->prom_node->name, "flashprom"))
					goto ebus_done;
			}
		}
	ebus_done:
		if (!edev)
			return -ENODEV;

		ebus_regs = of_get_property(edev->prom_node, "reg", &len);
		if (!ebus_regs || (len % sizeof(regs[0])) != 0) {
			printk("flash: Strange reg property size %d\n", len);
			return -ENODEV;
		}

		nregs = len / sizeof(ebus_regs[0]);

		flash.read_base = edev->resource[0].start;
		flash.read_size = ebus_regs[0].reg_size;

		if (nregs == 1) {
			flash.write_base = edev->resource[0].start;
			flash.write_size = ebus_regs[0].reg_size;
		} else if (nregs == 2) {
			flash.write_base = edev->resource[1].start;
			flash.write_size = ebus_regs[1].reg_size;
		} else {
			printk("flash: Strange number of regs %d\n", nregs);
			return -ENODEV;
		}

		flash.busy = 0;

#else
		return -ENODEV;
#endif
	}

	printk("OBP Flash: RD %lx[%lx] WR %lx[%lx]\n",
	       flash.read_base, flash.read_size,
	       flash.write_base, flash.write_size);

	err = misc_register(&flash_dev);
	if (err) {
		printk(KERN_ERR "flash: unable to get misc minor\n");
		return err;
	}

	return 0;
}

static void __exit flash_cleanup(void)
{
	misc_deregister(&flash_dev);
}

module_init(flash_init);
module_exit(flash_cleanup);
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/* $Id: flash.c,v 1.25 2001/12/21 04:56:16 davem Exp $
	2	* flash.c: Allow mmap access to the OBP Flash, for OBP updates.
	3	*
	4	* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
	5	*/
	6
1da177e4 LT	7	#include <linux/module.h>
	8	#include <linux/types.h>
	9	#include <linux/errno.h>
	10	#include <linux/miscdevice.h>
	11	#include <linux/slab.h>
	12	#include <linux/fcntl.h>
	13	#include <linux/poll.h>
	14	#include <linux/init.h>
	15	#include <linux/smp_lock.h>
	16	#include <linux/spinlock.h>
8a73709e	17	#include <linux/mm.h>
1da177e4 LT	18
	19	#include <asm/system.h>
	20	#include <asm/uaccess.h>
	21	#include <asm/pgtable.h>
	22	#include <asm/io.h>
	23	#include <asm/sbus.h>
	24	#include <asm/ebus.h>
	25	#include <asm/upa.h>
	26
	27	static DEFINE_SPINLOCK(flash_lock);
	28	static struct {
	29	unsigned long read_base; /* Physical read address */
	30	unsigned long write_base; /* Physical write address */
	31	unsigned long read_size; /* Size of read area */
	32	unsigned long write_size; /* Size of write area */
	33	unsigned long busy; /* In use? */
	34	} flash;
	35
	36	#define FLASH_MINOR 152
	37
	38	static int
	39	flash_mmap(struct file file, struct vm_area_struct vma)
	40	{
	41	unsigned long addr;
	42	unsigned long size;
	43
	44	spin_lock(&flash_lock);
	45	if (flash.read_base == flash.write_base) {
	46	addr = flash.read_base;
	47	size = flash.read_size;
	48	} else {
	49	if ((vma->vm_flags & VM_READ) &&
	50	(vma->vm_flags & VM_WRITE)) {
	51	spin_unlock(&flash_lock);
	52	return -EINVAL;
	53	}
	54	if (vma->vm_flags & VM_READ) {
	55	addr = flash.read_base;
	56	size = flash.read_size;
	57	} else if (vma->vm_flags & VM_WRITE) {
	58	addr = flash.write_base;
	59	size = flash.write_size;
	60	} else {
	61	spin_unlock(&flash_lock);
	62	return -ENXIO;
	63	}
	64	}
	65	spin_unlock(&flash_lock);
	66
	67	if ((vma->vm_pgoff << PAGE_SHIFT) > size)
	68	return -ENXIO;
	69	addr = vma->vm_pgoff + (addr >> PAGE_SHIFT);
	70
	71	if (vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT)) > size)
	72	size = vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT));
	73
14778d90	74	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1da177e4 LT	75
	76	if (io_remap_pfn_range(vma, vma->vm_start, addr, size, vma->vm_page_prot))
	77	return -EAGAIN;
	78
	79	return 0;
	80	}
	81
	82	static long long
	83	flash_llseek(struct file *file, long long offset, int origin)
	84	{
	85	lock_kernel();
	86	switch (origin) {
	87	case 0:
	88	file->f_pos = offset;
	89	break;
	90	case 1:
	91	file->f_pos += offset;
	92	if (file->f_pos > flash.read_size)
	93	file->f_pos = flash.read_size;
	94	break;
	95	case 2:
	96	file->f_pos = flash.read_size;
	97	break;
	98	default:
	99	unlock_kernel();
	100	return -EINVAL;
	101	}
	102	unlock_kernel();
	103	return file->f_pos;
	104	}
	105
	106	static ssize_t
	107	flash_read(struct file * file, char __user * buf,
	108	size_t count, loff_t *ppos)
	109	{
	110	unsigned long p = file->f_pos;
	111	int i;
	112
	113	if (count > flash.read_size - p)
	114	count = flash.read_size - p;
	115
	116	for (i = 0; i < count; i++) {
	117	u8 data = upa_readb(flash.read_base + p + i);
	118	if (put_user(data, buf))
	119	return -EFAULT;
	120	buf++;
	121	}
	122
	123	file->f_pos += count;
	124	return count;
	125	}
	126
	127	static int
	128	flash_open(struct inode inode, struct file file)
	129	{
78abb6ac AB	130	lock_kernel();
	131	if (test_and_set_bit(0, (void *)&flash.busy) != 0) {
	132	unlock_kernel();
1da177e4	133	return -EBUSY;
78abb6ac	134	}
1da177e4	135
78abb6ac	136	unlock_kernel();
1da177e4 LT	137	return 0;
	138	}
	139
	140	static int
	141	flash_release(struct inode inode, struct file file)
	142	{
	143	spin_lock(&flash_lock);
	144	flash.busy = 0;
	145	spin_unlock(&flash_lock);
	146
	147	return 0;
	148	}
	149
00977a59	150	static const struct file_operations flash_fops = {
1da177e4 LT	151	/* no write to the Flash, use mmap
	152	* and play flash dependent tricks.
	153	*/
	154	.owner = THIS_MODULE,
	155	.llseek = flash_llseek,
	156	.read = flash_read,
	157	.mmap = flash_mmap,
	158	.open = flash_open,
	159	.release = flash_release,
	160	};
	161
	162	static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };
	163
	164	static int __init flash_init(void)
	165	{
	166	struct sbus_bus *sbus;
	167	struct sbus_dev *sdev = NULL;
	168	#ifdef CONFIG_PCI
	169	struct linux_ebus *ebus;
	170	struct linux_ebus_device *edev = NULL;
	171	struct linux_prom_registers regs[2];
	172	int len, nregs;
	173	#endif
	174	int err;
	175
	176	for_all_sbusdev(sdev, sbus) {
	177	if (!strcmp(sdev->prom_name, "flashprom")) {
	178	if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) {
	179	flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) \|
	180	(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
	181	flash.read_size = sdev->reg_addrs[0].reg_size;
	182	flash.write_base = flash.read_base;
	183	flash.write_size = flash.read_size;
	184	} else {
	185	flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) \|
	186	(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
	187	flash.read_size = sdev->reg_addrs[0].reg_size;
	188	flash.write_base = ((unsigned long)sdev->reg_addrs[1].phys_addr) \|
	189	(((unsigned long)sdev->reg_addrs[1].which_io)<<32UL);
	190	flash.write_size = sdev->reg_addrs[1].reg_size;
	191	}
	192	flash.busy = 0;
	193	break;
	194	}
	195	}
	196	if (!sdev) {
	197	#ifdef CONFIG_PCI
ccf0dec6	198	const struct linux_prom_registers *ebus_regs;
690c8fd3	199
1da177e4 LT	200	for_each_ebus(ebus) {
1da177e4 LT	201	for_each_ebusdev(edev, ebus) {
690c8fd3	202	if (!strcmp(edev->prom_node->name, "flashprom"))
1da177e4 LT	203	goto ebus_done;
	204	}
	205	}
	206	ebus_done:
	207	if (!edev)
	208	return -ENODEV;
	209
690c8fd3 DM	210	ebus_regs = of_get_property(edev->prom_node, "reg", &len);
690c8fd3 DM	211	if (!ebus_regs \|\| (len % sizeof(regs[0])) != 0) {
1da177e4 LT	212	printk("flash: Strange reg property size %d\n", len);
	213	return -ENODEV;
	214	}
	215
690c8fd3	216	nregs = len / sizeof(ebus_regs[0]);
1da177e4 LT	217
1da177e4 LT	218	flash.read_base = edev->resource[0].start;
690c8fd3	219	flash.read_size = ebus_regs[0].reg_size;
1da177e4 LT	220
	221	if (nregs == 1) {
	222	flash.write_base = edev->resource[0].start;
690c8fd3	223	flash.write_size = ebus_regs[0].reg_size;
1da177e4 LT	224	} else if (nregs == 2) {
1da177e4 LT	225	flash.write_base = edev->resource[1].start;
690c8fd3	226	flash.write_size = ebus_regs[1].reg_size;
1da177e4 LT	227	} else {
	228	printk("flash: Strange number of regs %d\n", nregs);
	229	return -ENODEV;
	230	}
	231
	232	flash.busy = 0;
	233
	234	#else
	235	return -ENODEV;
	236	#endif
	237	}
	238
	239	printk("OBP Flash: RD %lx[%lx] WR %lx[%lx]\n",
	240	flash.read_base, flash.read_size,
	241	flash.write_base, flash.write_size);
	242
	243	err = misc_register(&flash_dev);
	244	if (err) {
	245	printk(KERN_ERR "flash: unable to get misc minor\n");
	246	return err;
	247	}
	248
	249	return 0;
	250	}
	251
	252	static void __exit flash_cleanup(void)
	253	{
	254	misc_deregister(&flash_dev);
	255	}
	256
	257	module_init(flash_init);
	258	module_exit(flash_cleanup);
	259	MODULE_LICENSE("GPL");