linux/drivers/atm/idt77105.c
Kees Cook b784ecba51 atm: idt77105: Drop needless setup_timer()
Calling setup_timer() is redundant when DEFINE_TIMER() has been used.

Cc: Chas Williams <3chas3@gmail.com>
Cc: linux-atm-general@lists.sourceforge.net
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 14:15:21 -07:00

375 lines
11 KiB
C

/* drivers/atm/idt77105.c - IDT77105 (PHY) driver */
/* Written 1999 by Greg Banks, NEC Australia <gnb@linuxfan.com>. Based on suni.c */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/atmdev.h>
#include <linux/sonet.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/capability.h>
#include <linux/atm_idt77105.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <asm/param.h>
#include <linux/uaccess.h>
#include "idt77105.h"
#undef GENERAL_DEBUG
#ifdef GENERAL_DEBUG
#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
#else
#define DPRINTK(format,args...)
#endif
struct idt77105_priv {
struct idt77105_stats stats; /* link diagnostics */
struct atm_dev *dev; /* device back-pointer */
struct idt77105_priv *next;
int loop_mode;
unsigned char old_mcr; /* storage of MCR reg while signal lost */
};
static DEFINE_SPINLOCK(idt77105_priv_lock);
#define PRIV(dev) ((struct idt77105_priv *) dev->phy_data)
#define PUT(val,reg) dev->ops->phy_put(dev,val,IDT77105_##reg)
#define GET(reg) dev->ops->phy_get(dev,IDT77105_##reg)
static void idt77105_stats_timer_func(unsigned long);
static void idt77105_restart_timer_func(unsigned long);
static DEFINE_TIMER(stats_timer, idt77105_stats_timer_func, 0, 0);
static DEFINE_TIMER(restart_timer, idt77105_restart_timer_func, 0, 0);
static int start_timer = 1;
static struct idt77105_priv *idt77105_all = NULL;
/*
* Retrieve the value of one of the IDT77105's counters.
* `counter' is one of the IDT77105_CTRSEL_* constants.
*/
static u16 get_counter(struct atm_dev *dev, int counter)
{
u16 val;
/* write the counter bit into PHY register 6 */
PUT(counter, CTRSEL);
/* read the low 8 bits from register 4 */
val = GET(CTRLO);
/* read the high 8 bits from register 5 */
val |= GET(CTRHI)<<8;
return val;
}
/*
* Timer function called every second to gather statistics
* from the 77105. This is done because the h/w registers
* will overflow if not read at least once per second. The
* kernel's stats are much higher precision. Also, having
* a separate copy of the stats allows implementation of
* an ioctl which gathers the stats *without* zero'ing them.
*/
static void idt77105_stats_timer_func(unsigned long dummy)
{
struct idt77105_priv *walk;
struct atm_dev *dev;
struct idt77105_stats *stats;
DPRINTK("IDT77105 gathering statistics\n");
for (walk = idt77105_all; walk; walk = walk->next) {
dev = walk->dev;
stats = &walk->stats;
stats->symbol_errors += get_counter(dev, IDT77105_CTRSEL_SEC);
stats->tx_cells += get_counter(dev, IDT77105_CTRSEL_TCC);
stats->rx_cells += get_counter(dev, IDT77105_CTRSEL_RCC);
stats->rx_hec_errors += get_counter(dev, IDT77105_CTRSEL_RHEC);
}
if (!start_timer) mod_timer(&stats_timer,jiffies+IDT77105_STATS_TIMER_PERIOD);
}
/*
* A separate timer func which handles restarting PHY chips which
* have had the cable re-inserted after being pulled out. This is
* done by polling the Good Signal Bit in the Interrupt Status
* register every 5 seconds. The other technique (checking Good
* Signal Bit in the interrupt handler) cannot be used because PHY
* interrupts need to be disabled when the cable is pulled out
* to avoid lots of spurious cell error interrupts.
*/
static void idt77105_restart_timer_func(unsigned long dummy)
{
struct idt77105_priv *walk;
struct atm_dev *dev;
unsigned char istat;
DPRINTK("IDT77105 checking for cable re-insertion\n");
for (walk = idt77105_all; walk; walk = walk->next) {
dev = walk->dev;
if (dev->signal != ATM_PHY_SIG_LOST)
continue;
istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
if (istat & IDT77105_ISTAT_GOODSIG) {
/* Found signal again */
atm_dev_signal_change(dev, ATM_PHY_SIG_FOUND);
printk(KERN_NOTICE "%s(itf %d): signal detected again\n",
dev->type,dev->number);
/* flush the receive FIFO */
PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
/* re-enable interrupts */
PUT( walk->old_mcr ,MCR);
}
}
if (!start_timer) mod_timer(&restart_timer,jiffies+IDT77105_RESTART_TIMER_PERIOD);
}
static int fetch_stats(struct atm_dev *dev,struct idt77105_stats __user *arg,int zero)
{
unsigned long flags;
struct idt77105_stats stats;
spin_lock_irqsave(&idt77105_priv_lock, flags);
memcpy(&stats, &PRIV(dev)->stats, sizeof(struct idt77105_stats));
if (zero)
memset(&PRIV(dev)->stats, 0, sizeof(struct idt77105_stats));
spin_unlock_irqrestore(&idt77105_priv_lock, flags);
if (arg == NULL)
return 0;
return copy_to_user(arg, &stats,
sizeof(struct idt77105_stats)) ? -EFAULT : 0;
}
static int set_loopback(struct atm_dev *dev,int mode)
{
int diag;
diag = GET(DIAG) & ~IDT77105_DIAG_LCMASK;
switch (mode) {
case ATM_LM_NONE:
break;
case ATM_LM_LOC_ATM:
diag |= IDT77105_DIAG_LC_PHY_LOOPBACK;
break;
case ATM_LM_RMT_ATM:
diag |= IDT77105_DIAG_LC_LINE_LOOPBACK;
break;
default:
return -EINVAL;
}
PUT(diag,DIAG);
printk(KERN_NOTICE "%s(%d) Loopback mode is: %s\n", dev->type,
dev->number,
(mode == ATM_LM_NONE ? "NONE" :
(mode == ATM_LM_LOC_ATM ? "DIAG (local)" :
(mode == IDT77105_DIAG_LC_LINE_LOOPBACK ? "LOOP (remote)" :
"unknown")))
);
PRIV(dev)->loop_mode = mode;
return 0;
}
static int idt77105_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg)
{
printk(KERN_NOTICE "%s(%d) idt77105_ioctl() called\n",dev->type,dev->number);
switch (cmd) {
case IDT77105_GETSTATZ:
if (!capable(CAP_NET_ADMIN)) return -EPERM;
/* fall through */
case IDT77105_GETSTAT:
return fetch_stats(dev, arg, cmd == IDT77105_GETSTATZ);
case ATM_SETLOOP:
return set_loopback(dev,(int)(unsigned long) arg);
case ATM_GETLOOP:
return put_user(PRIV(dev)->loop_mode,(int __user *)arg) ?
-EFAULT : 0;
case ATM_QUERYLOOP:
return put_user(ATM_LM_LOC_ATM | ATM_LM_RMT_ATM,
(int __user *) arg) ? -EFAULT : 0;
default:
return -ENOIOCTLCMD;
}
}
static void idt77105_int(struct atm_dev *dev)
{
unsigned char istat;
istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
DPRINTK("IDT77105 generated an interrupt, istat=%02x\n", (unsigned)istat);
if (istat & IDT77105_ISTAT_RSCC) {
/* Rx Signal Condition Change - line went up or down */
if (istat & IDT77105_ISTAT_GOODSIG) { /* signal detected again */
/* This should not happen (restart timer does it) but JIC */
atm_dev_signal_change(dev, ATM_PHY_SIG_FOUND);
} else { /* signal lost */
/*
* Disable interrupts and stop all transmission and
* reception - the restart timer will restore these.
*/
PRIV(dev)->old_mcr = GET(MCR);
PUT(
(PRIV(dev)->old_mcr|
IDT77105_MCR_DREC|
IDT77105_MCR_DRIC|
IDT77105_MCR_HALTTX
) & ~IDT77105_MCR_EIP, MCR);
atm_dev_signal_change(dev, ATM_PHY_SIG_LOST);
printk(KERN_NOTICE "%s(itf %d): signal lost\n",
dev->type,dev->number);
}
}
if (istat & IDT77105_ISTAT_RFO) {
/* Rx FIFO Overrun -- perform a FIFO flush */
PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
printk(KERN_NOTICE "%s(itf %d): receive FIFO overrun\n",
dev->type,dev->number);
}
#ifdef GENERAL_DEBUG
if (istat & (IDT77105_ISTAT_HECERR | IDT77105_ISTAT_SCR |
IDT77105_ISTAT_RSE)) {
/* normally don't care - just report in stats */
printk(KERN_NOTICE "%s(itf %d): received cell with error\n",
dev->type,dev->number);
}
#endif
}
static int idt77105_start(struct atm_dev *dev)
{
unsigned long flags;
if (!(dev->dev_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
return -ENOMEM;
PRIV(dev)->dev = dev;
spin_lock_irqsave(&idt77105_priv_lock, flags);
PRIV(dev)->next = idt77105_all;
idt77105_all = PRIV(dev);
spin_unlock_irqrestore(&idt77105_priv_lock, flags);
memset(&PRIV(dev)->stats,0,sizeof(struct idt77105_stats));
/* initialise dev->signal from Good Signal Bit */
atm_dev_signal_change(dev,
GET(ISTAT) & IDT77105_ISTAT_GOODSIG ?
ATM_PHY_SIG_FOUND : ATM_PHY_SIG_LOST);
if (dev->signal == ATM_PHY_SIG_LOST)
printk(KERN_WARNING "%s(itf %d): no signal\n",dev->type,
dev->number);
/* initialise loop mode from hardware */
switch ( GET(DIAG) & IDT77105_DIAG_LCMASK ) {
case IDT77105_DIAG_LC_NORMAL:
PRIV(dev)->loop_mode = ATM_LM_NONE;
break;
case IDT77105_DIAG_LC_PHY_LOOPBACK:
PRIV(dev)->loop_mode = ATM_LM_LOC_ATM;
break;
case IDT77105_DIAG_LC_LINE_LOOPBACK:
PRIV(dev)->loop_mode = ATM_LM_RMT_ATM;
break;
}
/* enable interrupts, e.g. on loss of signal */
PRIV(dev)->old_mcr = GET(MCR);
if (dev->signal == ATM_PHY_SIG_FOUND) {
PRIV(dev)->old_mcr |= IDT77105_MCR_EIP;
PUT(PRIV(dev)->old_mcr, MCR);
}
idt77105_stats_timer_func(0); /* clear 77105 counters */
(void) fetch_stats(dev,NULL,1); /* clear kernel counters */
spin_lock_irqsave(&idt77105_priv_lock, flags);
if (start_timer) {
start_timer = 0;
stats_timer.expires = jiffies+IDT77105_STATS_TIMER_PERIOD;
add_timer(&stats_timer);
restart_timer.expires = jiffies+IDT77105_RESTART_TIMER_PERIOD;
add_timer(&restart_timer);
}
spin_unlock_irqrestore(&idt77105_priv_lock, flags);
return 0;
}
static int idt77105_stop(struct atm_dev *dev)
{
struct idt77105_priv *walk, *prev;
DPRINTK("%s(itf %d): stopping IDT77105\n",dev->type,dev->number);
/* disable interrupts */
PUT( GET(MCR) & ~IDT77105_MCR_EIP, MCR );
/* detach private struct from atm_dev & free */
for (prev = NULL, walk = idt77105_all ;
walk != NULL;
prev = walk, walk = walk->next) {
if (walk->dev == dev) {
if (prev != NULL)
prev->next = walk->next;
else
idt77105_all = walk->next;
dev->phy = NULL;
dev->dev_data = NULL;
kfree(walk);
break;
}
}
return 0;
}
static const struct atmphy_ops idt77105_ops = {
.start = idt77105_start,
.ioctl = idt77105_ioctl,
.interrupt = idt77105_int,
.stop = idt77105_stop,
};
int idt77105_init(struct atm_dev *dev)
{
dev->phy = &idt77105_ops;
return 0;
}
EXPORT_SYMBOL(idt77105_init);
static void __exit idt77105_exit(void)
{
/* turn off timers */
del_timer_sync(&stats_timer);
del_timer_sync(&restart_timer);
}
module_exit(idt77105_exit);
MODULE_LICENSE("GPL");