linux/drivers/sbus/char/display7seg.c

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/* display7seg.c - Driver implementation for the 7-segment display
* present on Sun Microsystems CP1400 and CP1500
*
* Copyright (c) 2000 Eric Brower (ebrower@usa.net)
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/major.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h> /* request_region */
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <asm/atomic.h>
#include <asm/uaccess.h> /* put_/get_user */
#include <asm/io.h>
#include <asm/display7seg.h>
#define D7S_MINOR 193
#define DRIVER_NAME "d7s"
#define PFX DRIVER_NAME ": "
static int sol_compat = 0; /* Solaris compatibility mode */
/* Solaris compatibility flag -
* The Solaris implementation omits support for several
* documented driver features (ref Sun doc 806-0180-03).
* By default, this module supports the documented driver
* abilities, rather than the Solaris implementation:
*
* 1) Device ALWAYS reverts to OBP-specified FLIPPED mode
* upon closure of device or module unload.
* 2) Device ioctls D7SIOCRD/D7SIOCWR honor toggling of
* FLIP bit
*
* If you wish the device to operate as under Solaris,
* omitting above features, set this parameter to non-zero.
*/
module_param(sol_compat, int, 0);
MODULE_PARM_DESC(sol_compat,
"Disables documented functionality omitted from Solaris driver");
MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
MODULE_DESCRIPTION("7-Segment Display driver for Sun Microsystems CP1400/1500");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("d7s");
struct d7s {
void __iomem *regs;
bool flipped;
};
struct d7s *d7s_device;
/*
* Register block address- see header for details
* -----------------------------------------
* | DP | ALARM | FLIP | 4 | 3 | 2 | 1 | 0 |
* -----------------------------------------
*
* DP - Toggles decimal point on/off
* ALARM - Toggles "Alarm" LED green/red
* FLIP - Inverts display for upside-down mounted board
* bits 0-4 - 7-segment display contents
*/
static atomic_t d7s_users = ATOMIC_INIT(0);
static int d7s_open(struct inode *inode, struct file *f)
{
if (D7S_MINOR != iminor(inode))
return -ENODEV;
cycle_kernel_lock();
atomic_inc(&d7s_users);
return 0;
}
static int d7s_release(struct inode *inode, struct file *f)
{
/* Reset flipped state to OBP default only if
* no other users have the device open and we
* are not operating in solaris-compat mode
*/
if (atomic_dec_and_test(&d7s_users) && !sol_compat) {
struct d7s *p = d7s_device;
u8 regval = 0;
regval = readb(p->regs);
if (p->flipped)
regval |= D7S_FLIP;
else
regval &= ~D7S_FLIP;
writeb(regval, p->regs);
}
return 0;
}
static long d7s_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct d7s *p = d7s_device;
u8 regs = readb(p->regs);
int error = 0;
u8 ireg = 0;
if (D7S_MINOR != iminor(file->f_path.dentry->d_inode))
return -ENODEV;
lock_kernel();
switch (cmd) {
case D7SIOCWR:
/* assign device register values we mask-out D7S_FLIP
* if in sol_compat mode
*/
if (get_user(ireg, (int __user *) arg)) {
error = -EFAULT;
break;
}
if (sol_compat) {
if (regs & D7S_FLIP)
ireg |= D7S_FLIP;
else
ireg &= ~D7S_FLIP;
}
writeb(ireg, p->regs);
break;
case D7SIOCRD:
/* retrieve device register values
* NOTE: Solaris implementation returns D7S_FLIP bit
* as toggled by user, even though it does not honor it.
* This driver will not misinform you about the state
* of your hardware while in sol_compat mode
*/
if (put_user(regs, (int __user *) arg)) {
error = -EFAULT;
break;
}
break;
case D7SIOCTM:
/* toggle device mode-- flip display orientation */
if (regs & D7S_FLIP)
regs &= ~D7S_FLIP;
else
regs |= D7S_FLIP;
writeb(regs, p->regs);
break;
};
unlock_kernel();
return error;
}
static const struct file_operations d7s_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = d7s_ioctl,
.compat_ioctl = d7s_ioctl,
.open = d7s_open,
.release = d7s_release,
};
static struct miscdevice d7s_miscdev = {
.minor = D7S_MINOR,
.name = DRIVER_NAME,
.fops = &d7s_fops
};
static int __devinit d7s_probe(struct of_device *op,
const struct of_device_id *match)
{
struct device_node *opts;
int err = -EINVAL;
struct d7s *p;
u8 regs;
if (d7s_device)
goto out;
p = kzalloc(sizeof(*p), GFP_KERNEL);
err = -ENOMEM;
if (!p)
goto out;
p->regs = of_ioremap(&op->resource[0], 0, sizeof(u8), "d7s");
if (!p->regs) {
printk(KERN_ERR PFX "Cannot map chip registers\n");
goto out_free;
}
err = misc_register(&d7s_miscdev);
if (err) {
printk(KERN_ERR PFX "Unable to acquire miscdevice minor %i\n",
D7S_MINOR);
goto out_iounmap;
}
/* OBP option "d7s-flipped?" is honored as default for the
* device, and reset default when detached
*/
regs = readb(p->regs);
opts = of_find_node_by_path("/options");
if (opts &&
of_get_property(opts, "d7s-flipped?", NULL))
p->flipped = true;
if (p->flipped)
regs |= D7S_FLIP;
else
regs &= ~D7S_FLIP;
writeb(regs, p->regs);
printk(KERN_INFO PFX "7-Segment Display%s at [%s:0x%llx] %s\n",
op->dev.of_node->full_name,
(regs & D7S_FLIP) ? " (FLIPPED)" : "",
op->resource[0].start,
sol_compat ? "in sol_compat mode" : "");
dev_set_drvdata(&op->dev, p);
d7s_device = p;
err = 0;
out:
return err;
out_iounmap:
of_iounmap(&op->resource[0], p->regs, sizeof(u8));
out_free:
kfree(p);
goto out;
}
static int __devexit d7s_remove(struct of_device *op)
{
struct d7s *p = dev_get_drvdata(&op->dev);
u8 regs = readb(p->regs);
/* Honor OBP d7s-flipped? unless operating in solaris-compat mode */
if (sol_compat) {
if (p->flipped)
regs |= D7S_FLIP;
else
regs &= ~D7S_FLIP;
writeb(regs, p->regs);
}
misc_deregister(&d7s_miscdev);
of_iounmap(&op->resource[0], p->regs, sizeof(u8));
kfree(p);
return 0;
}
static const struct of_device_id d7s_match[] = {
{
.name = "display7seg",
},
{},
};
MODULE_DEVICE_TABLE(of, d7s_match);
static struct of_platform_driver d7s_driver = {
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = d7s_match,
},
.probe = d7s_probe,
.remove = __devexit_p(d7s_remove),
};
static int __init d7s_init(void)
{
return of_register_driver(&d7s_driver, &of_bus_type);
}
static void __exit d7s_exit(void)
{
of_unregister_driver(&d7s_driver);
}
module_init(d7s_init);
module_exit(d7s_exit);