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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/wdrtas.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/wdrtas.c')
-rw-r--r--drivers/watchdog/wdrtas.c628
1 files changed, 628 insertions, 0 deletions
diff --git a/drivers/watchdog/wdrtas.c b/drivers/watchdog/wdrtas.c
new file mode 100644
index 000000000..c00627825
--- /dev/null
+++ b/drivers/watchdog/wdrtas.c
@@ -0,0 +1,628 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * FIXME: add wdrtas_get_status and wdrtas_get_boot_status as soon as
+ * RTAS calls are available
+ */
+
+/*
+ * RTAS watchdog driver
+ *
+ * (C) Copyright IBM Corp. 2005
+ * device driver to exploit watchdog RTAS functions
+ *
+ * Authors : Utz Bacher <utz.bacher@de.ibm.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/uaccess.h>
+
+#include <asm/rtas.h>
+
+#define WDRTAS_MAGIC_CHAR 42
+#define WDRTAS_SUPPORTED_MASK (WDIOF_SETTIMEOUT | \
+ WDIOF_MAGICCLOSE)
+
+MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>");
+MODULE_DESCRIPTION("RTAS watchdog driver");
+MODULE_LICENSE("GPL");
+
+static bool wdrtas_nowayout = WATCHDOG_NOWAYOUT;
+static atomic_t wdrtas_miscdev_open = ATOMIC_INIT(0);
+static char wdrtas_expect_close;
+
+static int wdrtas_interval;
+
+#define WDRTAS_THERMAL_SENSOR 3
+static int wdrtas_token_get_sensor_state;
+#define WDRTAS_SURVEILLANCE_IND 9000
+static int wdrtas_token_set_indicator;
+#define WDRTAS_SP_SPI 28
+static int wdrtas_token_get_sp;
+static int wdrtas_token_event_scan;
+
+#define WDRTAS_DEFAULT_INTERVAL 300
+
+#define WDRTAS_LOGBUFFER_LEN 128
+static char wdrtas_logbuffer[WDRTAS_LOGBUFFER_LEN];
+
+
+/*** watchdog access functions */
+
+/**
+ * wdrtas_set_interval - sets the watchdog interval
+ * @interval: new interval
+ *
+ * returns 0 on success, <0 on failures
+ *
+ * wdrtas_set_interval sets the watchdog keepalive interval by calling the
+ * RTAS function set-indicator (surveillance). The unit of interval is
+ * seconds.
+ */
+
+static int wdrtas_set_interval(int interval)
+{
+ long result;
+ static int print_msg = 10;
+
+ /* rtas uses minutes */
+ interval = (interval + 59) / 60;
+
+ result = rtas_call(wdrtas_token_set_indicator, 3, 1, NULL,
+ WDRTAS_SURVEILLANCE_IND, 0, interval);
+ if (result < 0 && print_msg) {
+ pr_err("setting the watchdog to %i timeout failed: %li\n",
+ interval, result);
+ print_msg--;
+ }
+
+ return result;
+}
+
+#define WDRTAS_SP_SPI_LEN 4
+
+/**
+ * wdrtas_get_interval - returns the current watchdog interval
+ * @fallback_value: value (in seconds) to use, if the RTAS call fails
+ *
+ * returns the interval
+ *
+ * wdrtas_get_interval returns the current watchdog keepalive interval
+ * as reported by the RTAS function ibm,get-system-parameter. The unit
+ * of the return value is seconds.
+ */
+static int wdrtas_get_interval(int fallback_value)
+{
+ long result;
+ char value[WDRTAS_SP_SPI_LEN];
+
+ spin_lock(&rtas_data_buf_lock);
+ memset(rtas_data_buf, 0, WDRTAS_SP_SPI_LEN);
+ result = rtas_call(wdrtas_token_get_sp, 3, 1, NULL,
+ WDRTAS_SP_SPI, __pa(rtas_data_buf),
+ WDRTAS_SP_SPI_LEN);
+
+ memcpy(value, rtas_data_buf, WDRTAS_SP_SPI_LEN);
+ spin_unlock(&rtas_data_buf_lock);
+
+ if (value[0] != 0 || value[1] != 2 || value[3] != 0 || result < 0) {
+ pr_warn("could not get sp_spi watchdog timeout (%li). Continuing\n",
+ result);
+ return fallback_value;
+ }
+
+ /* rtas uses minutes */
+ return ((int)value[2]) * 60;
+}
+
+/**
+ * wdrtas_timer_start - starts watchdog
+ *
+ * wdrtas_timer_start starts the watchdog by calling the RTAS function
+ * set-interval (surveillance)
+ */
+static void wdrtas_timer_start(void)
+{
+ wdrtas_set_interval(wdrtas_interval);
+}
+
+/**
+ * wdrtas_timer_stop - stops watchdog
+ *
+ * wdrtas_timer_stop stops the watchdog timer by calling the RTAS function
+ * set-interval (surveillance)
+ */
+static void wdrtas_timer_stop(void)
+{
+ wdrtas_set_interval(0);
+}
+
+/**
+ * wdrtas_timer_keepalive - resets watchdog timer to keep system alive
+ *
+ * wdrtas_timer_keepalive restarts the watchdog timer by calling the
+ * RTAS function event-scan and repeats these calls as long as there are
+ * events available. All events will be dumped.
+ */
+static void wdrtas_timer_keepalive(void)
+{
+ long result;
+
+ do {
+ result = rtas_call(wdrtas_token_event_scan, 4, 1, NULL,
+ RTAS_EVENT_SCAN_ALL_EVENTS, 0,
+ (void *)__pa(wdrtas_logbuffer),
+ WDRTAS_LOGBUFFER_LEN);
+ if (result < 0)
+ pr_err("event-scan failed: %li\n", result);
+ if (result == 0)
+ print_hex_dump(KERN_INFO, "dumping event, data: ",
+ DUMP_PREFIX_OFFSET, 16, 1,
+ wdrtas_logbuffer, WDRTAS_LOGBUFFER_LEN, false);
+ } while (result == 0);
+}
+
+/**
+ * wdrtas_get_temperature - returns current temperature
+ *
+ * returns temperature or <0 on failures
+ *
+ * wdrtas_get_temperature returns the current temperature in Fahrenheit. It
+ * uses the RTAS call get-sensor-state, token 3 to do so
+ */
+static int wdrtas_get_temperature(void)
+{
+ int result;
+ int temperature = 0;
+
+ result = rtas_get_sensor(WDRTAS_THERMAL_SENSOR, 0, &temperature);
+
+ if (result < 0)
+ pr_warn("reading the thermal sensor failed: %i\n", result);
+ else
+ temperature = ((temperature * 9) / 5) + 32; /* fahrenheit */
+
+ return temperature;
+}
+
+/**
+ * wdrtas_get_status - returns the status of the watchdog
+ *
+ * returns a bitmask of defines WDIOF_... as defined in
+ * include/linux/watchdog.h
+ */
+static int wdrtas_get_status(void)
+{
+ return 0; /* TODO */
+}
+
+/**
+ * wdrtas_get_boot_status - returns the reason for the last boot
+ *
+ * returns a bitmask of defines WDIOF_... as defined in
+ * include/linux/watchdog.h, indicating why the watchdog rebooted the system
+ */
+static int wdrtas_get_boot_status(void)
+{
+ return 0; /* TODO */
+}
+
+/*** watchdog API and operations stuff */
+
+/* wdrtas_write - called when watchdog device is written to
+ * @file: file structure
+ * @buf: user buffer with data
+ * @len: amount to data written
+ * @ppos: position in file
+ *
+ * returns the number of successfully processed characters, which is always
+ * the number of bytes passed to this function
+ *
+ * wdrtas_write processes all the data given to it and looks for the magic
+ * character 'V'. This character allows the watchdog device to be closed
+ * properly.
+ */
+static ssize_t wdrtas_write(struct file *file, const char __user *buf,
+ size_t len, loff_t *ppos)
+{
+ int i;
+ char c;
+
+ if (!len)
+ goto out;
+
+ if (!wdrtas_nowayout) {
+ wdrtas_expect_close = 0;
+ /* look for 'V' */
+ for (i = 0; i < len; i++) {
+ if (get_user(c, buf + i))
+ return -EFAULT;
+ /* allow to close device */
+ if (c == 'V')
+ wdrtas_expect_close = WDRTAS_MAGIC_CHAR;
+ }
+ }
+
+ wdrtas_timer_keepalive();
+
+out:
+ return len;
+}
+
+/**
+ * wdrtas_ioctl - ioctl function for the watchdog device
+ * @file: file structure
+ * @cmd: command for ioctl
+ * @arg: argument pointer
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * wdrtas_ioctl implements the watchdog API ioctls
+ */
+
+static long wdrtas_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int __user *argp = (void __user *)arg;
+ int i;
+ static const struct watchdog_info wdinfo = {
+ .options = WDRTAS_SUPPORTED_MASK,
+ .firmware_version = 0,
+ .identity = "wdrtas",
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &wdinfo, sizeof(wdinfo)))
+ return -EFAULT;
+ return 0;
+
+ case WDIOC_GETSTATUS:
+ i = wdrtas_get_status();
+ return put_user(i, argp);
+
+ case WDIOC_GETBOOTSTATUS:
+ i = wdrtas_get_boot_status();
+ return put_user(i, argp);
+
+ case WDIOC_GETTEMP:
+ if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE)
+ return -EOPNOTSUPP;
+
+ i = wdrtas_get_temperature();
+ return put_user(i, argp);
+
+ case WDIOC_SETOPTIONS:
+ if (get_user(i, argp))
+ return -EFAULT;
+ if (i & WDIOS_DISABLECARD)
+ wdrtas_timer_stop();
+ if (i & WDIOS_ENABLECARD) {
+ wdrtas_timer_keepalive();
+ wdrtas_timer_start();
+ }
+ /* not implemented. Done by H8
+ if (i & WDIOS_TEMPPANIC) {
+ } */
+ return 0;
+
+ case WDIOC_KEEPALIVE:
+ wdrtas_timer_keepalive();
+ return 0;
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(i, argp))
+ return -EFAULT;
+
+ if (wdrtas_set_interval(i))
+ return -EINVAL;
+
+ wdrtas_timer_keepalive();
+
+ if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE)
+ wdrtas_interval = i;
+ else
+ wdrtas_interval = wdrtas_get_interval(i);
+ fallthrough;
+
+ case WDIOC_GETTIMEOUT:
+ return put_user(wdrtas_interval, argp);
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+/**
+ * wdrtas_open - open function of watchdog device
+ * @inode: inode structure
+ * @file: file structure
+ *
+ * returns 0 on success, -EBUSY if the file has been opened already, <0 on
+ * other failures
+ *
+ * function called when watchdog device is opened
+ */
+static int wdrtas_open(struct inode *inode, struct file *file)
+{
+ /* only open once */
+ if (atomic_inc_return(&wdrtas_miscdev_open) > 1) {
+ atomic_dec(&wdrtas_miscdev_open);
+ return -EBUSY;
+ }
+
+ wdrtas_timer_start();
+ wdrtas_timer_keepalive();
+
+ return stream_open(inode, file);
+}
+
+/**
+ * wdrtas_close - close function of watchdog device
+ * @inode: inode structure
+ * @file: file structure
+ *
+ * returns 0 on success
+ *
+ * close function. Always succeeds
+ */
+static int wdrtas_close(struct inode *inode, struct file *file)
+{
+ /* only stop watchdog, if this was announced using 'V' before */
+ if (wdrtas_expect_close == WDRTAS_MAGIC_CHAR)
+ wdrtas_timer_stop();
+ else {
+ pr_warn("got unexpected close. Watchdog not stopped.\n");
+ wdrtas_timer_keepalive();
+ }
+
+ wdrtas_expect_close = 0;
+ atomic_dec(&wdrtas_miscdev_open);
+ return 0;
+}
+
+/**
+ * wdrtas_temp_read - gives back the temperature in fahrenheit
+ * @file: file structure
+ * @buf: user buffer
+ * @count: number of bytes to be read
+ * @ppos: position in file
+ *
+ * returns always 1 or -EFAULT in case of user space copy failures, <0 on
+ * other failures
+ *
+ * wdrtas_temp_read gives the temperature to the users by copying this
+ * value as one byte into the user space buffer. The unit is Fahrenheit...
+ */
+static ssize_t wdrtas_temp_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ int temperature = 0;
+
+ temperature = wdrtas_get_temperature();
+ if (temperature < 0)
+ return temperature;
+
+ if (copy_to_user(buf, &temperature, 1))
+ return -EFAULT;
+
+ return 1;
+}
+
+/**
+ * wdrtas_temp_open - open function of temperature device
+ * @inode: inode structure
+ * @file: file structure
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * function called when temperature device is opened
+ */
+static int wdrtas_temp_open(struct inode *inode, struct file *file)
+{
+ return stream_open(inode, file);
+}
+
+/**
+ * wdrtas_temp_close - close function of temperature device
+ * @inode: inode structure
+ * @file: file structure
+ *
+ * returns 0 on success
+ *
+ * close function. Always succeeds
+ */
+static int wdrtas_temp_close(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+/**
+ * wdrtas_reboot - reboot notifier function
+ * @nb: notifier block structure
+ * @code: reboot code
+ * @ptr: unused
+ *
+ * returns NOTIFY_DONE
+ *
+ * wdrtas_reboot stops the watchdog in case of a reboot
+ */
+static int wdrtas_reboot(struct notifier_block *this,
+ unsigned long code, void *ptr)
+{
+ if (code == SYS_DOWN || code == SYS_HALT)
+ wdrtas_timer_stop();
+
+ return NOTIFY_DONE;
+}
+
+/*** initialization stuff */
+
+static const struct file_operations wdrtas_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = wdrtas_write,
+ .unlocked_ioctl = wdrtas_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .open = wdrtas_open,
+ .release = wdrtas_close,
+};
+
+static struct miscdevice wdrtas_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdrtas_fops,
+};
+
+static const struct file_operations wdrtas_temp_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read = wdrtas_temp_read,
+ .open = wdrtas_temp_open,
+ .release = wdrtas_temp_close,
+};
+
+static struct miscdevice wdrtas_tempdev = {
+ .minor = TEMP_MINOR,
+ .name = "temperature",
+ .fops = &wdrtas_temp_fops,
+};
+
+static struct notifier_block wdrtas_notifier = {
+ .notifier_call = wdrtas_reboot,
+};
+
+/**
+ * wdrtas_get_tokens - reads in RTAS tokens
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * wdrtas_get_tokens reads in the tokens for the RTAS calls used in
+ * this watchdog driver. It tolerates, if "get-sensor-state" and
+ * "ibm,get-system-parameter" are not available.
+ */
+static int wdrtas_get_tokens(void)
+{
+ wdrtas_token_get_sensor_state = rtas_token("get-sensor-state");
+ if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE) {
+ pr_warn("couldn't get token for get-sensor-state. Trying to continue without temperature support.\n");
+ }
+
+ wdrtas_token_get_sp = rtas_token("ibm,get-system-parameter");
+ if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) {
+ pr_warn("couldn't get token for ibm,get-system-parameter. Trying to continue with a default timeout value of %i seconds.\n",
+ WDRTAS_DEFAULT_INTERVAL);
+ }
+
+ wdrtas_token_set_indicator = rtas_token("set-indicator");
+ if (wdrtas_token_set_indicator == RTAS_UNKNOWN_SERVICE) {
+ pr_err("couldn't get token for set-indicator. Terminating watchdog code.\n");
+ return -EIO;
+ }
+
+ wdrtas_token_event_scan = rtas_token("event-scan");
+ if (wdrtas_token_event_scan == RTAS_UNKNOWN_SERVICE) {
+ pr_err("couldn't get token for event-scan. Terminating watchdog code.\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * wdrtas_unregister_devs - unregisters the misc dev handlers
+ *
+ * wdrtas_register_devs unregisters the watchdog and temperature watchdog
+ * misc devs
+ */
+static void wdrtas_unregister_devs(void)
+{
+ misc_deregister(&wdrtas_miscdev);
+ if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE)
+ misc_deregister(&wdrtas_tempdev);
+}
+
+/**
+ * wdrtas_register_devs - registers the misc dev handlers
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * wdrtas_register_devs registers the watchdog and temperature watchdog
+ * misc devs
+ */
+static int wdrtas_register_devs(void)
+{
+ int result;
+
+ result = misc_register(&wdrtas_miscdev);
+ if (result) {
+ pr_err("couldn't register watchdog misc device. Terminating watchdog code.\n");
+ return result;
+ }
+
+ if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE) {
+ result = misc_register(&wdrtas_tempdev);
+ if (result) {
+ pr_warn("couldn't register watchdog temperature misc device. Continuing without temperature support.\n");
+ wdrtas_token_get_sensor_state = RTAS_UNKNOWN_SERVICE;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * wdrtas_init - init function of the watchdog driver
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * registers the file handlers and the reboot notifier
+ */
+static int __init wdrtas_init(void)
+{
+ if (wdrtas_get_tokens())
+ return -ENODEV;
+
+ if (wdrtas_register_devs())
+ return -ENODEV;
+
+ if (register_reboot_notifier(&wdrtas_notifier)) {
+ pr_err("could not register reboot notifier. Terminating watchdog code.\n");
+ wdrtas_unregister_devs();
+ return -ENODEV;
+ }
+
+ if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE)
+ wdrtas_interval = WDRTAS_DEFAULT_INTERVAL;
+ else
+ wdrtas_interval = wdrtas_get_interval(WDRTAS_DEFAULT_INTERVAL);
+
+ return 0;
+}
+
+/**
+ * wdrtas_exit - exit function of the watchdog driver
+ *
+ * unregisters the file handlers and the reboot notifier
+ */
+static void __exit wdrtas_exit(void)
+{
+ if (!wdrtas_nowayout)
+ wdrtas_timer_stop();
+
+ wdrtas_unregister_devs();
+
+ unregister_reboot_notifier(&wdrtas_notifier);
+}
+
+module_init(wdrtas_init);
+module_exit(wdrtas_exit);