![Arnd Bergmann](/assets/img/avatar_default.png)
All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
702 lines
16 KiB
C
702 lines
16 KiB
C
/* cpwd.c - driver implementation for hardware watchdog
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* timers found on Sun Microsystems CP1400 and CP1500 boards.
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*
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* This device supports both the generic Linux watchdog
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* interface and Solaris-compatible ioctls as best it is
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* able.
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*
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* NOTE: CP1400 systems appear to have a defective intr_mask
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* register on the PLD, preventing the disabling of
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* timer interrupts. We use a timer to periodically
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* reset 'stopped' watchdogs on affected platforms.
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*
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* Copyright (c) 2000 Eric Brower (ebrower@usa.net)
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* Copyright (C) 2008 David S. Miller <davem@davemloft.net>
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/errno.h>
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#include <linux/major.h>
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#include <linux/init.h>
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#include <linux/miscdevice.h>
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#include <linux/interrupt.h>
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#include <linux/ioport.h>
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#include <linux/timer.h>
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#include <linux/slab.h>
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#include <linux/smp_lock.h>
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#include <linux/io.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/uaccess.h>
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#include <asm/irq.h>
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#include <asm/watchdog.h>
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#define DRIVER_NAME "cpwd"
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#define PFX DRIVER_NAME ": "
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#define WD_OBPNAME "watchdog"
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#define WD_BADMODEL "SUNW,501-5336"
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#define WD_BTIMEOUT (jiffies + (HZ * 1000))
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#define WD_BLIMIT 0xFFFF
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#define WD0_MINOR 212
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#define WD1_MINOR 213
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#define WD2_MINOR 214
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/* Internal driver definitions. */
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#define WD0_ID 0
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#define WD1_ID 1
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#define WD2_ID 2
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#define WD_NUMDEVS 3
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#define WD_INTR_OFF 0
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#define WD_INTR_ON 1
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#define WD_STAT_INIT 0x01 /* Watchdog timer is initialized */
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#define WD_STAT_BSTOP 0x02 /* Watchdog timer is brokenstopped */
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#define WD_STAT_SVCD 0x04 /* Watchdog interrupt occurred */
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/* Register value definitions
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*/
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#define WD0_INTR_MASK 0x01 /* Watchdog device interrupt masks */
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#define WD1_INTR_MASK 0x02
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#define WD2_INTR_MASK 0x04
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#define WD_S_RUNNING 0x01 /* Watchdog device status running */
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#define WD_S_EXPIRED 0x02 /* Watchdog device status expired */
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struct cpwd {
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void __iomem *regs;
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spinlock_t lock;
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unsigned int irq;
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unsigned long timeout;
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bool enabled;
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bool reboot;
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bool broken;
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bool initialized;
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struct {
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struct miscdevice misc;
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void __iomem *regs;
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u8 intr_mask;
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u8 runstatus;
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u16 timeout;
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} devs[WD_NUMDEVS];
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};
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static struct cpwd *cpwd_device;
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/* Sun uses Altera PLD EPF8820ATC144-4
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* providing three hardware watchdogs:
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*
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* 1) RIC - sends an interrupt when triggered
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* 2) XIR - asserts XIR_B_RESET when triggered, resets CPU
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* 3) POR - asserts POR_B_RESET when triggered, resets CPU, backplane, board
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*
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*** Timer register block definition (struct wd_timer_regblk)
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*
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* dcntr and limit registers (halfword access):
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* -------------------
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* | 15 | ...| 1 | 0 |
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* -------------------
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* |- counter val -|
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* -------------------
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* dcntr - Current 16-bit downcounter value.
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* When downcounter reaches '0' watchdog expires.
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* Reading this register resets downcounter with
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* 'limit' value.
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* limit - 16-bit countdown value in 1/10th second increments.
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* Writing this register begins countdown with input value.
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* Reading from this register does not affect counter.
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* NOTES: After watchdog reset, dcntr and limit contain '1'
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*
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* status register (byte access):
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* ---------------------------
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* | 7 | ... | 2 | 1 | 0 |
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* --------------+------------
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* |- UNUSED -| EXP | RUN |
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* ---------------------------
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* status- Bit 0 - Watchdog is running
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* Bit 1 - Watchdog has expired
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*
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*** PLD register block definition (struct wd_pld_regblk)
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*
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* intr_mask register (byte access):
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* ---------------------------------
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* | 7 | ... | 3 | 2 | 1 | 0 |
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* +-------------+------------------
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* |- UNUSED -| WD3 | WD2 | WD1 |
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* ---------------------------------
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* WD3 - 1 == Interrupt disabled for watchdog 3
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* WD2 - 1 == Interrupt disabled for watchdog 2
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* WD1 - 1 == Interrupt disabled for watchdog 1
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*
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* pld_status register (byte access):
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* UNKNOWN, MAGICAL MYSTERY REGISTER
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*
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*/
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#define WD_TIMER_REGSZ 16
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#define WD0_OFF 0
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#define WD1_OFF (WD_TIMER_REGSZ * 1)
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#define WD2_OFF (WD_TIMER_REGSZ * 2)
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#define PLD_OFF (WD_TIMER_REGSZ * 3)
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#define WD_DCNTR 0x00
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#define WD_LIMIT 0x04
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#define WD_STATUS 0x08
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#define PLD_IMASK (PLD_OFF + 0x00)
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#define PLD_STATUS (PLD_OFF + 0x04)
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static struct timer_list cpwd_timer;
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static int wd0_timeout;
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static int wd1_timeout;
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static int wd2_timeout;
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module_param(wd0_timeout, int, 0);
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MODULE_PARM_DESC(wd0_timeout, "Default watchdog0 timeout in 1/10secs");
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module_param(wd1_timeout, int, 0);
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MODULE_PARM_DESC(wd1_timeout, "Default watchdog1 timeout in 1/10secs");
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module_param(wd2_timeout, int, 0);
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MODULE_PARM_DESC(wd2_timeout, "Default watchdog2 timeout in 1/10secs");
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MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
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MODULE_DESCRIPTION("Hardware watchdog driver for Sun Microsystems CP1400/1500");
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MODULE_LICENSE("GPL");
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MODULE_SUPPORTED_DEVICE("watchdog");
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static void cpwd_writew(u16 val, void __iomem *addr)
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{
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writew(cpu_to_le16(val), addr);
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}
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static u16 cpwd_readw(void __iomem *addr)
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{
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u16 val = readw(addr);
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return le16_to_cpu(val);
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}
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static void cpwd_writeb(u8 val, void __iomem *addr)
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{
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writeb(val, addr);
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}
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static u8 cpwd_readb(void __iomem *addr)
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{
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return readb(addr);
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}
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/* Enable or disable watchdog interrupts
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* Because of the CP1400 defect this should only be
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* called during initialzation or by wd_[start|stop]timer()
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*
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* index - sub-device index, or -1 for 'all'
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* enable - non-zero to enable interrupts, zero to disable
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*/
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static void cpwd_toggleintr(struct cpwd *p, int index, int enable)
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{
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unsigned char curregs = cpwd_readb(p->regs + PLD_IMASK);
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unsigned char setregs =
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(index == -1) ?
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(WD0_INTR_MASK | WD1_INTR_MASK | WD2_INTR_MASK) :
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(p->devs[index].intr_mask);
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if (enable == WD_INTR_ON)
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curregs &= ~setregs;
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else
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curregs |= setregs;
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cpwd_writeb(curregs, p->regs + PLD_IMASK);
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}
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/* Restarts timer with maximum limit value and
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* does not unset 'brokenstop' value.
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*/
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static void cpwd_resetbrokentimer(struct cpwd *p, int index)
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{
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cpwd_toggleintr(p, index, WD_INTR_ON);
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cpwd_writew(WD_BLIMIT, p->devs[index].regs + WD_LIMIT);
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}
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/* Timer method called to reset stopped watchdogs--
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* because of the PLD bug on CP1400, we cannot mask
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* interrupts within the PLD so me must continually
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* reset the timers ad infinitum.
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*/
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static void cpwd_brokentimer(unsigned long data)
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{
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struct cpwd *p = (struct cpwd *) data;
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int id, tripped = 0;
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/* kill a running timer instance, in case we
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* were called directly instead of by kernel timer
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*/
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if (timer_pending(&cpwd_timer))
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del_timer(&cpwd_timer);
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for (id = 0; id < WD_NUMDEVS; id++) {
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if (p->devs[id].runstatus & WD_STAT_BSTOP) {
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++tripped;
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cpwd_resetbrokentimer(p, id);
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}
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}
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if (tripped) {
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/* there is at least one timer brokenstopped-- reschedule */
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cpwd_timer.expires = WD_BTIMEOUT;
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add_timer(&cpwd_timer);
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}
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}
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/* Reset countdown timer with 'limit' value and continue countdown.
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* This will not start a stopped timer.
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*/
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static void cpwd_pingtimer(struct cpwd *p, int index)
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{
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if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING)
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cpwd_readw(p->devs[index].regs + WD_DCNTR);
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}
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/* Stop a running watchdog timer-- the timer actually keeps
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* running, but the interrupt is masked so that no action is
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* taken upon expiration.
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*/
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static void cpwd_stoptimer(struct cpwd *p, int index)
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{
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if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING) {
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cpwd_toggleintr(p, index, WD_INTR_OFF);
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if (p->broken) {
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p->devs[index].runstatus |= WD_STAT_BSTOP;
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cpwd_brokentimer((unsigned long) p);
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}
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}
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}
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/* Start a watchdog timer with the specified limit value
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* If the watchdog is running, it will be restarted with
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* the provided limit value.
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*
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* This function will enable interrupts on the specified
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* watchdog.
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*/
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static void cpwd_starttimer(struct cpwd *p, int index)
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{
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if (p->broken)
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p->devs[index].runstatus &= ~WD_STAT_BSTOP;
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p->devs[index].runstatus &= ~WD_STAT_SVCD;
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cpwd_writew(p->devs[index].timeout, p->devs[index].regs + WD_LIMIT);
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cpwd_toggleintr(p, index, WD_INTR_ON);
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}
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static int cpwd_getstatus(struct cpwd *p, int index)
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{
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unsigned char stat = cpwd_readb(p->devs[index].regs + WD_STATUS);
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unsigned char intr = cpwd_readb(p->devs[index].regs + PLD_IMASK);
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unsigned char ret = WD_STOPPED;
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/* determine STOPPED */
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if (!stat)
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return ret;
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/* determine EXPIRED vs FREERUN vs RUNNING */
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else if (WD_S_EXPIRED & stat) {
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ret = WD_EXPIRED;
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} else if (WD_S_RUNNING & stat) {
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if (intr & p->devs[index].intr_mask) {
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ret = WD_FREERUN;
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} else {
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/* Fudge WD_EXPIRED status for defective CP1400--
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* IF timer is running
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* AND brokenstop is set
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* AND an interrupt has been serviced
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* we are WD_EXPIRED.
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*
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* IF timer is running
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* AND brokenstop is set
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* AND no interrupt has been serviced
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* we are WD_FREERUN.
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*/
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if (p->broken &&
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(p->devs[index].runstatus & WD_STAT_BSTOP)) {
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if (p->devs[index].runstatus & WD_STAT_SVCD) {
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ret = WD_EXPIRED;
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} else {
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/* we could as well pretend
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* we are expired */
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ret = WD_FREERUN;
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}
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} else {
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ret = WD_RUNNING;
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}
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}
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}
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/* determine SERVICED */
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if (p->devs[index].runstatus & WD_STAT_SVCD)
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ret |= WD_SERVICED;
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return ret;
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}
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static irqreturn_t cpwd_interrupt(int irq, void *dev_id)
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{
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struct cpwd *p = dev_id;
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/* Only WD0 will interrupt-- others are NMI and we won't
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* see them here....
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*/
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spin_lock_irq(&p->lock);
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cpwd_stoptimer(p, WD0_ID);
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p->devs[WD0_ID].runstatus |= WD_STAT_SVCD;
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spin_unlock_irq(&p->lock);
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return IRQ_HANDLED;
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}
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static int cpwd_open(struct inode *inode, struct file *f)
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{
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struct cpwd *p = cpwd_device;
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lock_kernel();
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switch (iminor(inode)) {
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case WD0_MINOR:
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case WD1_MINOR:
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case WD2_MINOR:
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break;
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default:
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unlock_kernel();
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return -ENODEV;
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}
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/* Register IRQ on first open of device */
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if (!p->initialized) {
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if (request_irq(p->irq, &cpwd_interrupt,
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IRQF_SHARED, DRIVER_NAME, p)) {
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printk(KERN_ERR PFX "Cannot register IRQ %d\n",
|
|
p->irq);
|
|
unlock_kernel();
|
|
return -EBUSY;
|
|
}
|
|
p->initialized = true;
|
|
}
|
|
|
|
unlock_kernel();
|
|
|
|
return nonseekable_open(inode, f);
|
|
}
|
|
|
|
static int cpwd_release(struct inode *inode, struct file *file)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static long cpwd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
static const struct watchdog_info info = {
|
|
.options = WDIOF_SETTIMEOUT,
|
|
.firmware_version = 1,
|
|
.identity = DRIVER_NAME,
|
|
};
|
|
void __user *argp = (void __user *)arg;
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
int index = iminor(inode) - WD0_MINOR;
|
|
struct cpwd *p = cpwd_device;
|
|
int setopt = 0;
|
|
|
|
switch (cmd) {
|
|
/* Generic Linux IOCTLs */
|
|
case WDIOC_GETSUPPORT:
|
|
if (copy_to_user(argp, &info, sizeof(struct watchdog_info)))
|
|
return -EFAULT;
|
|
break;
|
|
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
if (put_user(0, (int __user *)argp))
|
|
return -EFAULT;
|
|
break;
|
|
|
|
case WDIOC_KEEPALIVE:
|
|
cpwd_pingtimer(p, index);
|
|
break;
|
|
|
|
case WDIOC_SETOPTIONS:
|
|
if (copy_from_user(&setopt, argp, sizeof(unsigned int)))
|
|
return -EFAULT;
|
|
|
|
if (setopt & WDIOS_DISABLECARD) {
|
|
if (p->enabled)
|
|
return -EINVAL;
|
|
cpwd_stoptimer(p, index);
|
|
} else if (setopt & WDIOS_ENABLECARD) {
|
|
cpwd_starttimer(p, index);
|
|
} else {
|
|
return -EINVAL;
|
|
}
|
|
break;
|
|
|
|
/* Solaris-compatible IOCTLs */
|
|
case WIOCGSTAT:
|
|
setopt = cpwd_getstatus(p, index);
|
|
if (copy_to_user(argp, &setopt, sizeof(unsigned int)))
|
|
return -EFAULT;
|
|
break;
|
|
|
|
case WIOCSTART:
|
|
cpwd_starttimer(p, index);
|
|
break;
|
|
|
|
case WIOCSTOP:
|
|
if (p->enabled)
|
|
return -EINVAL;
|
|
|
|
cpwd_stoptimer(p, index);
|
|
break;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static long cpwd_compat_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
int rval = -ENOIOCTLCMD;
|
|
|
|
switch (cmd) {
|
|
/* solaris ioctls are specific to this driver */
|
|
case WIOCSTART:
|
|
case WIOCSTOP:
|
|
case WIOCGSTAT:
|
|
lock_kernel();
|
|
rval = cpwd_ioctl(file, cmd, arg);
|
|
unlock_kernel();
|
|
break;
|
|
|
|
/* everything else is handled by the generic compat layer */
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return rval;
|
|
}
|
|
|
|
static ssize_t cpwd_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct cpwd *p = cpwd_device;
|
|
int index = iminor(inode);
|
|
|
|
if (count) {
|
|
cpwd_pingtimer(p, index);
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t cpwd_read(struct file *file, char __user *buffer,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static const struct file_operations cpwd_fops = {
|
|
.owner = THIS_MODULE,
|
|
.unlocked_ioctl = cpwd_ioctl,
|
|
.compat_ioctl = cpwd_compat_ioctl,
|
|
.open = cpwd_open,
|
|
.write = cpwd_write,
|
|
.read = cpwd_read,
|
|
.release = cpwd_release,
|
|
.llseek = no_llseek,
|
|
};
|
|
|
|
static int __devinit cpwd_probe(struct platform_device *op,
|
|
const struct of_device_id *match)
|
|
{
|
|
struct device_node *options;
|
|
const char *str_prop;
|
|
const void *prop_val;
|
|
int i, err = -EINVAL;
|
|
struct cpwd *p;
|
|
|
|
if (cpwd_device)
|
|
return -EINVAL;
|
|
|
|
p = kzalloc(sizeof(*p), GFP_KERNEL);
|
|
err = -ENOMEM;
|
|
if (!p) {
|
|
printk(KERN_ERR PFX "Unable to allocate struct cpwd.\n");
|
|
goto out;
|
|
}
|
|
|
|
p->irq = op->archdata.irqs[0];
|
|
|
|
spin_lock_init(&p->lock);
|
|
|
|
p->regs = of_ioremap(&op->resource[0], 0,
|
|
4 * WD_TIMER_REGSZ, DRIVER_NAME);
|
|
if (!p->regs) {
|
|
printk(KERN_ERR PFX "Unable to map registers.\n");
|
|
goto out_free;
|
|
}
|
|
|
|
options = of_find_node_by_path("/options");
|
|
err = -ENODEV;
|
|
if (!options) {
|
|
printk(KERN_ERR PFX "Unable to find /options node.\n");
|
|
goto out_iounmap;
|
|
}
|
|
|
|
prop_val = of_get_property(options, "watchdog-enable?", NULL);
|
|
p->enabled = (prop_val ? true : false);
|
|
|
|
prop_val = of_get_property(options, "watchdog-reboot?", NULL);
|
|
p->reboot = (prop_val ? true : false);
|
|
|
|
str_prop = of_get_property(options, "watchdog-timeout", NULL);
|
|
if (str_prop)
|
|
p->timeout = simple_strtoul(str_prop, NULL, 10);
|
|
|
|
/* CP1400s seem to have broken PLD implementations-- the
|
|
* interrupt_mask register cannot be written, so no timer
|
|
* interrupts can be masked within the PLD.
|
|
*/
|
|
str_prop = of_get_property(op->dev.of_node, "model", NULL);
|
|
p->broken = (str_prop && !strcmp(str_prop, WD_BADMODEL));
|
|
|
|
if (!p->enabled)
|
|
cpwd_toggleintr(p, -1, WD_INTR_OFF);
|
|
|
|
for (i = 0; i < WD_NUMDEVS; i++) {
|
|
static const char *cpwd_names[] = { "RIC", "XIR", "POR" };
|
|
static int *parms[] = { &wd0_timeout,
|
|
&wd1_timeout,
|
|
&wd2_timeout };
|
|
struct miscdevice *mp = &p->devs[i].misc;
|
|
|
|
mp->minor = WD0_MINOR + i;
|
|
mp->name = cpwd_names[i];
|
|
mp->fops = &cpwd_fops;
|
|
|
|
p->devs[i].regs = p->regs + (i * WD_TIMER_REGSZ);
|
|
p->devs[i].intr_mask = (WD0_INTR_MASK << i);
|
|
p->devs[i].runstatus &= ~WD_STAT_BSTOP;
|
|
p->devs[i].runstatus |= WD_STAT_INIT;
|
|
p->devs[i].timeout = p->timeout;
|
|
if (*parms[i])
|
|
p->devs[i].timeout = *parms[i];
|
|
|
|
err = misc_register(&p->devs[i].misc);
|
|
if (err) {
|
|
printk(KERN_ERR "Could not register misc device for "
|
|
"dev %d\n", i);
|
|
goto out_unregister;
|
|
}
|
|
}
|
|
|
|
if (p->broken) {
|
|
init_timer(&cpwd_timer);
|
|
cpwd_timer.function = cpwd_brokentimer;
|
|
cpwd_timer.data = (unsigned long) p;
|
|
cpwd_timer.expires = WD_BTIMEOUT;
|
|
|
|
printk(KERN_INFO PFX "PLD defect workaround enabled for "
|
|
"model " WD_BADMODEL ".\n");
|
|
}
|
|
|
|
dev_set_drvdata(&op->dev, p);
|
|
cpwd_device = p;
|
|
err = 0;
|
|
|
|
out:
|
|
return err;
|
|
|
|
out_unregister:
|
|
for (i--; i >= 0; i--)
|
|
misc_deregister(&p->devs[i].misc);
|
|
|
|
out_iounmap:
|
|
of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
|
|
|
|
out_free:
|
|
kfree(p);
|
|
goto out;
|
|
}
|
|
|
|
static int __devexit cpwd_remove(struct platform_device *op)
|
|
{
|
|
struct cpwd *p = dev_get_drvdata(&op->dev);
|
|
int i;
|
|
|
|
for (i = 0; i < 4; i++) {
|
|
misc_deregister(&p->devs[i].misc);
|
|
|
|
if (!p->enabled) {
|
|
cpwd_stoptimer(p, i);
|
|
if (p->devs[i].runstatus & WD_STAT_BSTOP)
|
|
cpwd_resetbrokentimer(p, i);
|
|
}
|
|
}
|
|
|
|
if (p->broken)
|
|
del_timer_sync(&cpwd_timer);
|
|
|
|
if (p->initialized)
|
|
free_irq(p->irq, p);
|
|
|
|
of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
|
|
kfree(p);
|
|
|
|
cpwd_device = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id cpwd_match[] = {
|
|
{
|
|
.name = "watchdog",
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, cpwd_match);
|
|
|
|
static struct of_platform_driver cpwd_driver = {
|
|
.driver = {
|
|
.name = DRIVER_NAME,
|
|
.owner = THIS_MODULE,
|
|
.of_match_table = cpwd_match,
|
|
},
|
|
.probe = cpwd_probe,
|
|
.remove = __devexit_p(cpwd_remove),
|
|
};
|
|
|
|
static int __init cpwd_init(void)
|
|
{
|
|
return of_register_platform_driver(&cpwd_driver);
|
|
}
|
|
|
|
static void __exit cpwd_exit(void)
|
|
{
|
|
of_unregister_platform_driver(&cpwd_driver);
|
|
}
|
|
|
|
module_init(cpwd_init);
|
|
module_exit(cpwd_exit);
|