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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/char/nwbutton.c
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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/char/nwbutton.c')
-rw-r--r--drivers/char/nwbutton.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/char/nwbutton.c b/drivers/char/nwbutton.c
new file mode 100644
index 000000000..ea378c0ed
--- /dev/null
+++ b/drivers/char/nwbutton.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NetWinder Button Driver-
+ * Copyright (C) Alex Holden <alex@linuxhacker.org> 1998, 1999.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+
+#include <linux/uaccess.h>
+#include <asm/irq.h>
+#include <asm/mach-types.h>
+
+#define __NWBUTTON_C /* Tell the header file who we are */
+#include "nwbutton.h"
+
+static void button_sequence_finished(struct timer_list *unused);
+
+static int button_press_count; /* The count of button presses */
+/* Times for the end of a sequence */
+static DEFINE_TIMER(button_timer, button_sequence_finished);
+static DECLARE_WAIT_QUEUE_HEAD(button_wait_queue); /* Used for blocking read */
+static char button_output_buffer[32]; /* Stores data to write out of device */
+static int bcount; /* The number of bytes in the buffer */
+static int bdelay = BUTTON_DELAY; /* The delay, in jiffies */
+static struct button_callback button_callback_list[32]; /* The callback list */
+static int callback_count; /* The number of callbacks registered */
+static int reboot_count = NUM_PRESSES_REBOOT; /* Number of presses to reboot */
+
+/*
+ * This function is called by other drivers to register a callback function
+ * to be called when a particular number of button presses occurs.
+ * The callback list is a static array of 32 entries (I somehow doubt many
+ * people are ever going to want to register more than 32 different actions
+ * to be performed by the kernel on different numbers of button presses ;).
+ * However, if an attempt to register a 33rd entry (perhaps a stuck loop
+ * somewhere registering the same entry over and over?) it will fail to
+ * do so and return -ENOMEM. If an attempt is made to register a null pointer,
+ * it will fail to do so and return -EINVAL.
+ * Because callbacks can be unregistered at random the list can become
+ * fragmented, so we need to search through the list until we find the first
+ * free entry.
+ *
+ * FIXME: Has anyone spotted any locking functions int his code recently ??
+ */
+
+int button_add_callback (void (*callback) (void), int count)
+{
+ int lp = 0;
+ if (callback_count == 32) {
+ return -ENOMEM;
+ }
+ if (!callback) {
+ return -EINVAL;
+ }
+ callback_count++;
+ for (; (button_callback_list [lp].callback); lp++);
+ button_callback_list [lp].callback = callback;
+ button_callback_list [lp].count = count;
+ return 0;
+}
+
+/*
+ * This function is called by other drivers to deregister a callback function.
+ * If you attempt to unregister a callback which does not exist, it will fail
+ * with -EINVAL. If there is more than one entry with the same address,
+ * because it searches the list from end to beginning, it will unregister the
+ * last one to be registered first (FILO- First In Last Out).
+ * Note that this is not necessarily true if the entries are not submitted
+ * at the same time, because another driver could have unregistered a callback
+ * between the submissions creating a gap earlier in the list, which would
+ * be filled first at submission time.
+ */
+
+int button_del_callback (void (*callback) (void))
+{
+ int lp = 31;
+ if (!callback) {
+ return -EINVAL;
+ }
+ while (lp >= 0) {
+ if ((button_callback_list [lp].callback) == callback) {
+ button_callback_list [lp].callback = NULL;
+ button_callback_list [lp].count = 0;
+ callback_count--;
+ return 0;
+ }
+ lp--;
+ }
+ return -EINVAL;
+}
+
+/*
+ * This function is called by button_sequence_finished to search through the
+ * list of callback functions, and call any of them whose count argument
+ * matches the current count of button presses. It starts at the beginning
+ * of the list and works up to the end. It will refuse to follow a null
+ * pointer (which should never happen anyway).
+ */
+
+static void button_consume_callbacks (int bpcount)
+{
+ int lp = 0;
+ for (; lp <= 31; lp++) {
+ if ((button_callback_list [lp].count) == bpcount) {
+ if (button_callback_list [lp].callback) {
+ button_callback_list[lp].callback();
+ }
+ }
+ }
+}
+
+/*
+ * This function is called when the button_timer times out.
+ * ie. When you don't press the button for bdelay jiffies, this is taken to
+ * mean you have ended the sequence of key presses, and this function is
+ * called to wind things up (write the press_count out to /dev/button, call
+ * any matching registered function callbacks, initiate reboot, etc.).
+ */
+
+static void button_sequence_finished(struct timer_list *unused)
+{
+ if (IS_ENABLED(CONFIG_NWBUTTON_REBOOT) &&
+ button_press_count == reboot_count)
+ kill_cad_pid(SIGINT, 1); /* Ask init to reboot us */
+ button_consume_callbacks (button_press_count);
+ bcount = sprintf (button_output_buffer, "%d\n", button_press_count);
+ button_press_count = 0; /* Reset the button press counter */
+ wake_up_interruptible (&button_wait_queue);
+}
+
+/*
+ * This handler is called when the orange button is pressed (GPIO 10 of the
+ * SuperIO chip, which maps to logical IRQ 26). If the press_count is 0,
+ * this is the first press, so it starts a timer and increments the counter.
+ * If it is higher than 0, it deletes the old timer, starts a new one, and
+ * increments the counter.
+ */
+
+static irqreturn_t button_handler (int irq, void *dev_id)
+{
+ button_press_count++;
+ mod_timer(&button_timer, jiffies + bdelay);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * This function is called when a user space program attempts to read
+ * /dev/nwbutton. It puts the device to sleep on the wait queue until
+ * button_sequence_finished writes some data to the buffer and flushes
+ * the queue, at which point it writes the data out to the device and
+ * returns the number of characters it has written. This function is
+ * reentrant, so that many processes can be attempting to read from the
+ * device at any one time.
+ */
+
+static int button_read (struct file *filp, char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ DEFINE_WAIT(wait);
+ prepare_to_wait(&button_wait_queue, &wait, TASK_INTERRUPTIBLE);
+ schedule();
+ finish_wait(&button_wait_queue, &wait);
+ return (copy_to_user (buffer, &button_output_buffer, bcount))
+ ? -EFAULT : bcount;
+}
+
+/*
+ * This structure is the file operations structure, which specifies what
+ * callbacks functions the kernel should call when a user mode process
+ * attempts to perform these operations on the device.
+ */
+
+static const struct file_operations button_fops = {
+ .owner = THIS_MODULE,
+ .read = button_read,
+ .llseek = noop_llseek,
+};
+
+/*
+ * This structure is the misc device structure, which specifies the minor
+ * device number (158 in this case), the name of the device (for /proc/misc),
+ * and the address of the above file operations structure.
+ */
+
+static struct miscdevice button_misc_device = {
+ BUTTON_MINOR,
+ "nwbutton",
+ &button_fops,
+};
+
+/*
+ * This function is called to initialise the driver, either from misc.c at
+ * bootup if the driver is compiled into the kernel, or from init_module
+ * below at module insert time. It attempts to register the device node
+ * and the IRQ and fails with a warning message if either fails, though
+ * neither ever should because the device number and IRQ are unique to
+ * this driver.
+ */
+
+static int __init nwbutton_init(void)
+{
+ if (!machine_is_netwinder())
+ return -ENODEV;
+
+ printk (KERN_INFO "NetWinder Button Driver Version %s (C) Alex Holden "
+ "<alex@linuxhacker.org> 1998.\n", VERSION);
+
+ if (misc_register (&button_misc_device)) {
+ printk (KERN_WARNING "nwbutton: Couldn't register device 10, "
+ "%d.\n", BUTTON_MINOR);
+ return -EBUSY;
+ }
+
+ if (request_irq (IRQ_NETWINDER_BUTTON, button_handler, 0,
+ "nwbutton", NULL)) {
+ printk (KERN_WARNING "nwbutton: IRQ %d is not free.\n",
+ IRQ_NETWINDER_BUTTON);
+ misc_deregister (&button_misc_device);
+ return -EIO;
+ }
+ return 0;
+}
+
+static void __exit nwbutton_exit (void)
+{
+ free_irq (IRQ_NETWINDER_BUTTON, NULL);
+ misc_deregister (&button_misc_device);
+}
+
+
+MODULE_AUTHOR("Alex Holden");
+MODULE_LICENSE("GPL");
+
+module_init(nwbutton_init);
+module_exit(nwbutton_exit);