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Release 4.11 drivers/sbus/char/display7seg.c

/* 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/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/major.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h>		/* request_region */
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/atomic.h>
#include <linux/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 DEFINE_MUTEX(d7s_mutex);

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; atomic_inc(&d7s_users); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)3284.21%133.33%
Christoph Hellwig513.16%133.33%
Al Viro12.63%133.33%
Total38100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)4860.76%133.33%
David S. Miller2632.91%133.33%
Christoph Hellwig56.33%133.33%
Total79100.00%3100.00%


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_inode(file))) return -ENODEV; mutex_lock(&d7s_mutex); 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 */ regs ^= D7S_FLIP; writeb(regs, p->regs); break; } mutex_unlock(&d7s_mutex); return error; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)12165.05%220.00%
David S. Miller2714.52%110.00%
Christoph Hellwig2010.75%110.00%
Arnd Bergmann105.38%110.00%
Al Viro63.23%330.00%
Rasmus Villemoes10.54%110.00%
Andrew Morton10.54%110.00%
Total186100.00%10100.00%

static const struct file_operations d7s_fops = { .owner = THIS_MODULE, .unlocked_ioctl = d7s_ioctl, .compat_ioctl = d7s_ioctl, .open = d7s_open, .release = d7s_release, .llseek = noop_llseek, }; static struct miscdevice d7s_miscdev = { .minor = D7S_MINOR, .name = DRIVER_NAME, .fops = &d7s_fops };
static int d7s_probe(struct platform_device *op) { struct device_node *opts; int err = -EINVAL; struct d7s *p; u8 regs; if (d7s_device) goto out; p = devm_kzalloc(&op->dev, 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: goto out; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller17163.81%112.50%
Linus Torvalds (pre-git)8732.46%225.00%
Himangi Saraogi62.24%112.50%
Grant C. Likely20.75%225.00%
Sam Ravnborg10.37%112.50%
Chris Wilson10.37%112.50%
Total268100.00%8100.00%


static int d7s_remove(struct platform_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)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller6164.21%125.00%
Linus Torvalds (pre-git)3334.74%250.00%
Grant C. Likely11.05%125.00%
Total95100.00%4100.00%

static const struct of_device_id d7s_match[] = { { .name = "display7seg", }, {}, }; MODULE_DEVICE_TABLE(of, d7s_match); static struct platform_driver d7s_driver = { .driver = { .name = DRIVER_NAME, .of_match_table = d7s_match, }, .probe = d7s_probe, .remove = d7s_remove, }; module_platform_driver(d7s_driver);

Overall Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)43346.56%39.38%
David S. Miller37039.78%412.50%
Christoph Hellwig495.27%26.25%
Arnd Bergmann222.37%26.25%
Grant C. Likely101.08%412.50%
Himangi Saraogi90.97%13.12%
Rusty Russell80.86%13.12%
Al Viro70.75%39.38%
Linus Torvalds60.65%26.25%
Randy Dunlap40.43%13.12%
Tejun Heo30.32%13.12%
Axel Lin20.22%13.12%
Arun Sharma10.11%13.12%
Chris Wilson10.11%13.12%
Rasmus Villemoes10.11%13.12%
Arjan van de Ven10.11%13.12%
Andrew Morton10.11%13.12%
Peter Osterlund10.11%13.12%
Sam Ravnborg10.11%13.12%
Total930100.00%32100.00%
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