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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/gnss/core.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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/gnss/core.c')
-rw-r--r--drivers/gnss/core.c421
1 files changed, 421 insertions, 0 deletions
diff --git a/drivers/gnss/core.c b/drivers/gnss/core.c
new file mode 100644
index 000000000..77a4b280c
--- /dev/null
+++ b/drivers/gnss/core.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * GNSS receiver core
+ *
+ * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cdev.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/gnss.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+
+#define GNSS_FLAG_HAS_WRITE_RAW BIT(0)
+
+#define GNSS_MINORS 16
+
+static DEFINE_IDA(gnss_minors);
+static dev_t gnss_first;
+
+/* FIFO size must be a power of two */
+#define GNSS_READ_FIFO_SIZE 4096
+#define GNSS_WRITE_BUF_SIZE 1024
+
+#define to_gnss_device(d) container_of((d), struct gnss_device, dev)
+
+static int gnss_open(struct inode *inode, struct file *file)
+{
+ struct gnss_device *gdev;
+ int ret = 0;
+
+ gdev = container_of(inode->i_cdev, struct gnss_device, cdev);
+
+ get_device(&gdev->dev);
+
+ stream_open(inode, file);
+ file->private_data = gdev;
+
+ down_write(&gdev->rwsem);
+ if (gdev->disconnected) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ if (gdev->count++ == 0) {
+ ret = gdev->ops->open(gdev);
+ if (ret)
+ gdev->count--;
+ }
+unlock:
+ up_write(&gdev->rwsem);
+
+ if (ret)
+ put_device(&gdev->dev);
+
+ return ret;
+}
+
+static int gnss_release(struct inode *inode, struct file *file)
+{
+ struct gnss_device *gdev = file->private_data;
+
+ down_write(&gdev->rwsem);
+ if (gdev->disconnected)
+ goto unlock;
+
+ if (--gdev->count == 0) {
+ gdev->ops->close(gdev);
+ kfifo_reset(&gdev->read_fifo);
+ }
+unlock:
+ up_write(&gdev->rwsem);
+
+ put_device(&gdev->dev);
+
+ return 0;
+}
+
+static ssize_t gnss_read(struct file *file, char __user *buf,
+ size_t count, loff_t *pos)
+{
+ struct gnss_device *gdev = file->private_data;
+ unsigned int copied;
+ int ret;
+
+ mutex_lock(&gdev->read_mutex);
+ while (kfifo_is_empty(&gdev->read_fifo)) {
+ mutex_unlock(&gdev->read_mutex);
+
+ if (gdev->disconnected)
+ return 0;
+
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ ret = wait_event_interruptible(gdev->read_queue,
+ gdev->disconnected ||
+ !kfifo_is_empty(&gdev->read_fifo));
+ if (ret)
+ return -ERESTARTSYS;
+
+ mutex_lock(&gdev->read_mutex);
+ }
+
+ ret = kfifo_to_user(&gdev->read_fifo, buf, count, &copied);
+ if (ret == 0)
+ ret = copied;
+
+ mutex_unlock(&gdev->read_mutex);
+
+ return ret;
+}
+
+static ssize_t gnss_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *pos)
+{
+ struct gnss_device *gdev = file->private_data;
+ size_t written = 0;
+ int ret;
+
+ if (gdev->disconnected)
+ return -EIO;
+
+ if (!count)
+ return 0;
+
+ if (!(gdev->flags & GNSS_FLAG_HAS_WRITE_RAW))
+ return -EIO;
+
+ /* Ignoring O_NONBLOCK, write_raw() is synchronous. */
+
+ ret = mutex_lock_interruptible(&gdev->write_mutex);
+ if (ret)
+ return -ERESTARTSYS;
+
+ for (;;) {
+ size_t n = count - written;
+
+ if (n > GNSS_WRITE_BUF_SIZE)
+ n = GNSS_WRITE_BUF_SIZE;
+
+ if (copy_from_user(gdev->write_buf, buf, n)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ /*
+ * Assumes write_raw can always accept GNSS_WRITE_BUF_SIZE
+ * bytes.
+ *
+ * FIXME: revisit
+ */
+ down_read(&gdev->rwsem);
+ if (!gdev->disconnected)
+ ret = gdev->ops->write_raw(gdev, gdev->write_buf, n);
+ else
+ ret = -EIO;
+ up_read(&gdev->rwsem);
+
+ if (ret < 0)
+ break;
+
+ written += ret;
+ buf += ret;
+
+ if (written == count)
+ break;
+ }
+
+ if (written)
+ ret = written;
+out_unlock:
+ mutex_unlock(&gdev->write_mutex);
+
+ return ret;
+}
+
+static __poll_t gnss_poll(struct file *file, poll_table *wait)
+{
+ struct gnss_device *gdev = file->private_data;
+ __poll_t mask = 0;
+
+ poll_wait(file, &gdev->read_queue, wait);
+
+ if (!kfifo_is_empty(&gdev->read_fifo))
+ mask |= EPOLLIN | EPOLLRDNORM;
+ if (gdev->disconnected)
+ mask |= EPOLLHUP;
+
+ return mask;
+}
+
+static const struct file_operations gnss_fops = {
+ .owner = THIS_MODULE,
+ .open = gnss_open,
+ .release = gnss_release,
+ .read = gnss_read,
+ .write = gnss_write,
+ .poll = gnss_poll,
+ .llseek = no_llseek,
+};
+
+static struct class *gnss_class;
+
+static void gnss_device_release(struct device *dev)
+{
+ struct gnss_device *gdev = to_gnss_device(dev);
+
+ kfree(gdev->write_buf);
+ kfifo_free(&gdev->read_fifo);
+ ida_free(&gnss_minors, gdev->id);
+ kfree(gdev);
+}
+
+struct gnss_device *gnss_allocate_device(struct device *parent)
+{
+ struct gnss_device *gdev;
+ struct device *dev;
+ int id;
+ int ret;
+
+ gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
+ if (!gdev)
+ return NULL;
+
+ id = ida_alloc_max(&gnss_minors, GNSS_MINORS - 1, GFP_KERNEL);
+ if (id < 0) {
+ kfree(gdev);
+ return NULL;
+ }
+
+ gdev->id = id;
+
+ dev = &gdev->dev;
+ device_initialize(dev);
+ dev->devt = gnss_first + id;
+ dev->class = gnss_class;
+ dev->parent = parent;
+ dev->release = gnss_device_release;
+ dev_set_drvdata(dev, gdev);
+ dev_set_name(dev, "gnss%d", id);
+
+ init_rwsem(&gdev->rwsem);
+ mutex_init(&gdev->read_mutex);
+ mutex_init(&gdev->write_mutex);
+ init_waitqueue_head(&gdev->read_queue);
+
+ ret = kfifo_alloc(&gdev->read_fifo, GNSS_READ_FIFO_SIZE, GFP_KERNEL);
+ if (ret)
+ goto err_put_device;
+
+ gdev->write_buf = kzalloc(GNSS_WRITE_BUF_SIZE, GFP_KERNEL);
+ if (!gdev->write_buf)
+ goto err_put_device;
+
+ cdev_init(&gdev->cdev, &gnss_fops);
+ gdev->cdev.owner = THIS_MODULE;
+
+ return gdev;
+
+err_put_device:
+ put_device(dev);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(gnss_allocate_device);
+
+void gnss_put_device(struct gnss_device *gdev)
+{
+ put_device(&gdev->dev);
+}
+EXPORT_SYMBOL_GPL(gnss_put_device);
+
+int gnss_register_device(struct gnss_device *gdev)
+{
+ int ret;
+
+ /* Set a flag which can be accessed without holding the rwsem. */
+ if (gdev->ops->write_raw != NULL)
+ gdev->flags |= GNSS_FLAG_HAS_WRITE_RAW;
+
+ ret = cdev_device_add(&gdev->cdev, &gdev->dev);
+ if (ret) {
+ dev_err(&gdev->dev, "failed to add device: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gnss_register_device);
+
+void gnss_deregister_device(struct gnss_device *gdev)
+{
+ down_write(&gdev->rwsem);
+ gdev->disconnected = true;
+ if (gdev->count) {
+ wake_up_interruptible(&gdev->read_queue);
+ gdev->ops->close(gdev);
+ }
+ up_write(&gdev->rwsem);
+
+ cdev_device_del(&gdev->cdev, &gdev->dev);
+}
+EXPORT_SYMBOL_GPL(gnss_deregister_device);
+
+/*
+ * Caller guarantees serialisation.
+ *
+ * Must not be called for a closed device.
+ */
+int gnss_insert_raw(struct gnss_device *gdev, const unsigned char *buf,
+ size_t count)
+{
+ int ret;
+
+ ret = kfifo_in(&gdev->read_fifo, buf, count);
+
+ wake_up_interruptible(&gdev->read_queue);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gnss_insert_raw);
+
+static const char * const gnss_type_names[GNSS_TYPE_COUNT] = {
+ [GNSS_TYPE_NMEA] = "NMEA",
+ [GNSS_TYPE_SIRF] = "SiRF",
+ [GNSS_TYPE_UBX] = "UBX",
+ [GNSS_TYPE_MTK] = "MTK",
+};
+
+static const char *gnss_type_name(const struct gnss_device *gdev)
+{
+ const char *name = NULL;
+
+ if (gdev->type < GNSS_TYPE_COUNT)
+ name = gnss_type_names[gdev->type];
+
+ if (!name)
+ dev_WARN(&gdev->dev, "type name not defined\n");
+
+ return name;
+}
+
+static ssize_t type_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct gnss_device *gdev = to_gnss_device(dev);
+
+ return sprintf(buf, "%s\n", gnss_type_name(gdev));
+}
+static DEVICE_ATTR_RO(type);
+
+static struct attribute *gnss_attrs[] = {
+ &dev_attr_type.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(gnss);
+
+static int gnss_uevent(const struct device *dev, struct kobj_uevent_env *env)
+{
+ const struct gnss_device *gdev = to_gnss_device(dev);
+ int ret;
+
+ ret = add_uevent_var(env, "GNSS_TYPE=%s", gnss_type_name(gdev));
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int __init gnss_module_init(void)
+{
+ int ret;
+
+ ret = alloc_chrdev_region(&gnss_first, 0, GNSS_MINORS, "gnss");
+ if (ret < 0) {
+ pr_err("failed to allocate device numbers: %d\n", ret);
+ return ret;
+ }
+
+ gnss_class = class_create(THIS_MODULE, "gnss");
+ if (IS_ERR(gnss_class)) {
+ ret = PTR_ERR(gnss_class);
+ pr_err("failed to create class: %d\n", ret);
+ goto err_unregister_chrdev;
+ }
+
+ gnss_class->dev_groups = gnss_groups;
+ gnss_class->dev_uevent = gnss_uevent;
+
+ pr_info("GNSS driver registered with major %d\n", MAJOR(gnss_first));
+
+ return 0;
+
+err_unregister_chrdev:
+ unregister_chrdev_region(gnss_first, GNSS_MINORS);
+
+ return ret;
+}
+module_init(gnss_module_init);
+
+static void __exit gnss_module_exit(void)
+{
+ class_destroy(gnss_class);
+ unregister_chrdev_region(gnss_first, GNSS_MINORS);
+ ida_destroy(&gnss_minors);
+}
+module_exit(gnss_module_exit);
+
+MODULE_AUTHOR("Johan Hovold <johan@kernel.org>");
+MODULE_DESCRIPTION("GNSS receiver core");
+MODULE_LICENSE("GPL v2");