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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/watchdog/w83977f_wdt.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/watchdog/w83977f_wdt.c')
-rw-r--r--drivers/watchdog/w83977f_wdt.c525
1 files changed, 525 insertions, 0 deletions
diff --git a/drivers/watchdog/w83977f_wdt.c b/drivers/watchdog/w83977f_wdt.c
new file mode 100644
index 000000000..31bf21cea
--- /dev/null
+++ b/drivers/watchdog/w83977f_wdt.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * W83977F Watchdog Timer Driver for Winbond W83977F I/O Chip
+ *
+ * (c) Copyright 2005 Jose Goncalves <jose.goncalves@inov.pt>
+ *
+ * Based on w83877f_wdt.c by Scott Jennings,
+ * and wdt977.c by Woody Suwalski
+ *
+ * -----------------------
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/watchdog.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+
+#define WATCHDOG_VERSION "1.00"
+#define WATCHDOG_NAME "W83977F WDT"
+
+#define IO_INDEX_PORT 0x3F0
+#define IO_DATA_PORT (IO_INDEX_PORT+1)
+
+#define UNLOCK_DATA 0x87
+#define LOCK_DATA 0xAA
+#define DEVICE_REGISTER 0x07
+
+#define DEFAULT_TIMEOUT 45 /* default timeout in seconds */
+
+static int timeout = DEFAULT_TIMEOUT;
+static int timeoutW; /* timeout in watchdog counter units */
+static unsigned long timer_alive;
+static int testmode;
+static char expect_close;
+static DEFINE_SPINLOCK(spinlock);
+
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout,
+ "Watchdog timeout in seconds (15..7635), default="
+ __MODULE_STRING(DEFAULT_TIMEOUT) ")");
+module_param(testmode, int, 0);
+MODULE_PARM_DESC(testmode, "Watchdog testmode (1 = no reboot), default=0");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout,
+ "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ * Start the watchdog
+ */
+
+static int wdt_start(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+
+ /* Unlock the SuperIO chip */
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+
+ /*
+ * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4.
+ * F2 has the timeout in watchdog counter units.
+ * F3 is set to enable watchdog LED blink at timeout.
+ * F4 is used to just clear the TIMEOUT'ed state (bit 0).
+ */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+ outb_p(0xF2, IO_INDEX_PORT);
+ outb_p(timeoutW, IO_DATA_PORT);
+ outb_p(0xF3, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+ outb_p(0xF4, IO_INDEX_PORT);
+ outb_p(0x00, IO_DATA_PORT);
+
+ /* Set device Aux2 active */
+ outb_p(0x30, IO_INDEX_PORT);
+ outb_p(0x01, IO_DATA_PORT);
+
+ /*
+ * Select device Aux1 (dev=7) to set GP16 as the watchdog output
+ * (in reg E6) and GP13 as the watchdog LED output (in reg E3).
+ * Map GP16 at pin 119.
+ * In test mode watch the bit 0 on F4 to indicate "triggered" or
+ * check watchdog LED on SBC.
+ */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x07, IO_DATA_PORT);
+ if (!testmode) {
+ unsigned pin_map;
+
+ outb_p(0xE6, IO_INDEX_PORT);
+ outb_p(0x0A, IO_DATA_PORT);
+ outb_p(0x2C, IO_INDEX_PORT);
+ pin_map = inb_p(IO_DATA_PORT);
+ pin_map |= 0x10;
+ pin_map &= ~(0x20);
+ outb_p(0x2C, IO_INDEX_PORT);
+ outb_p(pin_map, IO_DATA_PORT);
+ }
+ outb_p(0xE3, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+
+ /* Set device Aux1 active */
+ outb_p(0x30, IO_INDEX_PORT);
+ outb_p(0x01, IO_DATA_PORT);
+
+ /* Lock the SuperIO chip */
+ outb_p(LOCK_DATA, IO_INDEX_PORT);
+
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ pr_info("activated\n");
+
+ return 0;
+}
+
+/*
+ * Stop the watchdog
+ */
+
+static int wdt_stop(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+
+ /* Unlock the SuperIO chip */
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+
+ /*
+ * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4.
+ * F2 is reset to its default value (watchdog timer disabled).
+ * F3 is reset to its default state.
+ * F4 clears the TIMEOUT'ed state (bit 0) - back to default.
+ */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+ outb_p(0xF2, IO_INDEX_PORT);
+ outb_p(0xFF, IO_DATA_PORT);
+ outb_p(0xF3, IO_INDEX_PORT);
+ outb_p(0x00, IO_DATA_PORT);
+ outb_p(0xF4, IO_INDEX_PORT);
+ outb_p(0x00, IO_DATA_PORT);
+ outb_p(0xF2, IO_INDEX_PORT);
+ outb_p(0x00, IO_DATA_PORT);
+
+ /*
+ * Select device Aux1 (dev=7) to set GP16 (in reg E6) and
+ * Gp13 (in reg E3) as inputs.
+ */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x07, IO_DATA_PORT);
+ if (!testmode) {
+ outb_p(0xE6, IO_INDEX_PORT);
+ outb_p(0x01, IO_DATA_PORT);
+ }
+ outb_p(0xE3, IO_INDEX_PORT);
+ outb_p(0x01, IO_DATA_PORT);
+
+ /* Lock the SuperIO chip */
+ outb_p(LOCK_DATA, IO_INDEX_PORT);
+
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ pr_info("shutdown\n");
+
+ return 0;
+}
+
+/*
+ * Send a keepalive ping to the watchdog
+ * This is done by simply re-writing the timeout to reg. 0xF2
+ */
+
+static int wdt_keepalive(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+
+ /* Unlock the SuperIO chip */
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+
+ /* Select device Aux2 (device=8) to kick watchdog reg F2 */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+ outb_p(0xF2, IO_INDEX_PORT);
+ outb_p(timeoutW, IO_DATA_PORT);
+
+ /* Lock the SuperIO chip */
+ outb_p(LOCK_DATA, IO_INDEX_PORT);
+
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ return 0;
+}
+
+/*
+ * Set the watchdog timeout value
+ */
+
+static int wdt_set_timeout(int t)
+{
+ unsigned int tmrval;
+
+ /*
+ * Convert seconds to watchdog counter time units, rounding up.
+ * On PCM-5335 watchdog units are 30 seconds/step with 15 sec startup
+ * value. This information is supplied in the PCM-5335 manual and was
+ * checked by me on a real board. This is a bit strange because W83977f
+ * datasheet says counter unit is in minutes!
+ */
+ if (t < 15)
+ return -EINVAL;
+
+ tmrval = ((t + 15) + 29) / 30;
+
+ if (tmrval > 255)
+ return -EINVAL;
+
+ /*
+ * timeout is the timeout in seconds,
+ * timeoutW is the timeout in watchdog counter units.
+ */
+ timeoutW = tmrval;
+ timeout = (timeoutW * 30) - 15;
+ return 0;
+}
+
+/*
+ * Get the watchdog status
+ */
+
+static int wdt_get_status(int *status)
+{
+ int new_status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+
+ /* Unlock the SuperIO chip */
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+ outb_p(UNLOCK_DATA, IO_INDEX_PORT);
+
+ /* Select device Aux2 (device=8) to read watchdog reg F4 */
+ outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
+ outb_p(0x08, IO_DATA_PORT);
+ outb_p(0xF4, IO_INDEX_PORT);
+ new_status = inb_p(IO_DATA_PORT);
+
+ /* Lock the SuperIO chip */
+ outb_p(LOCK_DATA, IO_INDEX_PORT);
+
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ *status = 0;
+ if (new_status & 1)
+ *status |= WDIOF_CARDRESET;
+
+ return 0;
+}
+
+
+/*
+ * /dev/watchdog handling
+ */
+
+static int wdt_open(struct inode *inode, struct file *file)
+{
+ /* If the watchdog is alive we don't need to start it again */
+ if (test_and_set_bit(0, &timer_alive))
+ return -EBUSY;
+
+ if (nowayout)
+ __module_get(THIS_MODULE);
+
+ wdt_start();
+ return stream_open(inode, file);
+}
+
+static int wdt_release(struct inode *inode, struct file *file)
+{
+ /*
+ * Shut off the timer.
+ * Lock it in if it's a module and we set nowayout
+ */
+ if (expect_close == 42) {
+ wdt_stop();
+ clear_bit(0, &timer_alive);
+ } else {
+ wdt_keepalive();
+ pr_crit("unexpected close, not stopping watchdog!\n");
+ }
+ expect_close = 0;
+ return 0;
+}
+
+/*
+ * wdt_write:
+ * @file: file handle to the watchdog
+ * @buf: buffer to write (unused as data does not matter here
+ * @count: count of bytes
+ * @ppos: pointer to the position to write. No seeks allowed
+ *
+ * A write to a watchdog device is defined as a keepalive signal. Any
+ * write of data will do, as we don't define content meaning.
+ */
+
+static ssize_t wdt_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ /* See if we got the magic character 'V' and reload the timer */
+ if (count) {
+ if (!nowayout) {
+ size_t ofs;
+
+ /* note: just in case someone wrote the
+ magic character long ago */
+ expect_close = 0;
+
+ /* scan to see whether or not we got the
+ magic character */
+ for (ofs = 0; ofs != count; ofs++) {
+ char c;
+ if (get_user(c, buf + ofs))
+ return -EFAULT;
+ if (c == 'V')
+ expect_close = 42;
+ }
+ }
+
+ /* someone wrote to us, we should restart timer */
+ wdt_keepalive();
+ }
+ return count;
+}
+
+/*
+ * wdt_ioctl:
+ * @inode: inode of the device
+ * @file: file handle to the device
+ * @cmd: watchdog command
+ * @arg: argument pointer
+ *
+ * The watchdog API defines a common set of functions for all watchdogs
+ * according to their available features.
+ */
+
+static const struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
+ .firmware_version = 1,
+ .identity = WATCHDOG_NAME,
+};
+
+static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int status;
+ int new_options, retval = -EINVAL;
+ int new_timeout;
+ union {
+ struct watchdog_info __user *ident;
+ int __user *i;
+ } uarg;
+
+ uarg.i = (int __user *)arg;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(uarg.ident, &ident,
+ sizeof(ident)) ? -EFAULT : 0;
+
+ case WDIOC_GETSTATUS:
+ wdt_get_status(&status);
+ return put_user(status, uarg.i);
+
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, uarg.i);
+
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_options, uarg.i))
+ return -EFAULT;
+
+ if (new_options & WDIOS_DISABLECARD) {
+ wdt_stop();
+ retval = 0;
+ }
+
+ if (new_options & WDIOS_ENABLECARD) {
+ wdt_start();
+ retval = 0;
+ }
+
+ return retval;
+
+ case WDIOC_KEEPALIVE:
+ wdt_keepalive();
+ return 0;
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_timeout, uarg.i))
+ return -EFAULT;
+
+ if (wdt_set_timeout(new_timeout))
+ return -EINVAL;
+
+ wdt_keepalive();
+ fallthrough;
+
+ case WDIOC_GETTIMEOUT:
+ return put_user(timeout, uarg.i);
+
+ default:
+ return -ENOTTY;
+
+ }
+}
+
+static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ if (code == SYS_DOWN || code == SYS_HALT)
+ wdt_stop();
+ return NOTIFY_DONE;
+}
+
+static const struct file_operations wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = wdt_write,
+ .unlocked_ioctl = wdt_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .open = wdt_open,
+ .release = wdt_release,
+};
+
+static struct miscdevice wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdt_fops,
+};
+
+static struct notifier_block wdt_notifier = {
+ .notifier_call = wdt_notify_sys,
+};
+
+static int __init w83977f_wdt_init(void)
+{
+ int rc;
+
+ pr_info("driver v%s\n", WATCHDOG_VERSION);
+
+ /*
+ * Check that the timeout value is within it's range;
+ * if not reset to the default
+ */
+ if (wdt_set_timeout(timeout)) {
+ wdt_set_timeout(DEFAULT_TIMEOUT);
+ pr_info("timeout value must be 15 <= timeout <= 7635, using %d\n",
+ DEFAULT_TIMEOUT);
+ }
+
+ if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) {
+ pr_err("I/O address 0x%04x already in use\n", IO_INDEX_PORT);
+ rc = -EIO;
+ goto err_out;
+ }
+
+ rc = register_reboot_notifier(&wdt_notifier);
+ if (rc) {
+ pr_err("cannot register reboot notifier (err=%d)\n", rc);
+ goto err_out_region;
+ }
+
+ rc = misc_register(&wdt_miscdev);
+ if (rc) {
+ pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+ wdt_miscdev.minor, rc);
+ goto err_out_reboot;
+ }
+
+ pr_info("initialized. timeout=%d sec (nowayout=%d testmode=%d)\n",
+ timeout, nowayout, testmode);
+
+ return 0;
+
+err_out_reboot:
+ unregister_reboot_notifier(&wdt_notifier);
+err_out_region:
+ release_region(IO_INDEX_PORT, 2);
+err_out:
+ return rc;
+}
+
+static void __exit w83977f_wdt_exit(void)
+{
+ wdt_stop();
+ misc_deregister(&wdt_miscdev);
+ unregister_reboot_notifier(&wdt_notifier);
+ release_region(IO_INDEX_PORT, 2);
+}
+
+module_init(w83977f_wdt_init);
+module_exit(w83977f_wdt_exit);
+
+MODULE_AUTHOR("Jose Goncalves <jose.goncalves@inov.pt>");
+MODULE_DESCRIPTION("Driver for watchdog timer in W83977F I/O chip");
+MODULE_LICENSE("GPL");