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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/input/misc/rotary_encoder.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/input/misc/rotary_encoder.c')
-rw-r--r--drivers/input/misc/rotary_encoder.c370
1 files changed, 370 insertions, 0 deletions
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
new file mode 100644
index 000000000..6d613f2a0
--- /dev/null
+++ b/drivers/input/misc/rotary_encoder.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * rotary_encoder.c
+ *
+ * (c) 2009 Daniel Mack <daniel@caiaq.de>
+ * Copyright (C) 2011 Johan Hovold <jhovold@gmail.com>
+ *
+ * state machine code inspired by code from Tim Ruetz
+ *
+ * A generic driver for rotary encoders connected to GPIO lines.
+ * See file:Documentation/input/devices/rotary-encoder.rst for more information
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/property.h>
+
+#define DRV_NAME "rotary-encoder"
+
+enum rotary_encoder_encoding {
+ ROTENC_GRAY,
+ ROTENC_BINARY,
+};
+
+struct rotary_encoder {
+ struct input_dev *input;
+
+ struct mutex access_mutex;
+
+ u32 steps;
+ u32 axis;
+ bool relative_axis;
+ bool rollover;
+ enum rotary_encoder_encoding encoding;
+
+ unsigned int pos;
+
+ struct gpio_descs *gpios;
+
+ unsigned int *irq;
+
+ bool armed;
+ signed char dir; /* 1 - clockwise, -1 - CCW */
+
+ unsigned int last_stable;
+};
+
+static unsigned int rotary_encoder_get_state(struct rotary_encoder *encoder)
+{
+ int i;
+ unsigned int ret = 0;
+
+ for (i = 0; i < encoder->gpios->ndescs; ++i) {
+ int val = gpiod_get_value_cansleep(encoder->gpios->desc[i]);
+
+ /* convert from gray encoding to normal */
+ if (encoder->encoding == ROTENC_GRAY && ret & 1)
+ val = !val;
+
+ ret = ret << 1 | val;
+ }
+
+ return ret & 3;
+}
+
+static void rotary_encoder_report_event(struct rotary_encoder *encoder)
+{
+ if (encoder->relative_axis) {
+ input_report_rel(encoder->input,
+ encoder->axis, encoder->dir);
+ } else {
+ unsigned int pos = encoder->pos;
+
+ if (encoder->dir < 0) {
+ /* turning counter-clockwise */
+ if (encoder->rollover)
+ pos += encoder->steps;
+ if (pos)
+ pos--;
+ } else {
+ /* turning clockwise */
+ if (encoder->rollover || pos < encoder->steps)
+ pos++;
+ }
+
+ if (encoder->rollover)
+ pos %= encoder->steps;
+
+ encoder->pos = pos;
+ input_report_abs(encoder->input, encoder->axis, encoder->pos);
+ }
+
+ input_sync(encoder->input);
+}
+
+static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
+{
+ struct rotary_encoder *encoder = dev_id;
+ unsigned int state;
+
+ mutex_lock(&encoder->access_mutex);
+
+ state = rotary_encoder_get_state(encoder);
+
+ switch (state) {
+ case 0x0:
+ if (encoder->armed) {
+ rotary_encoder_report_event(encoder);
+ encoder->armed = false;
+ }
+ break;
+
+ case 0x1:
+ case 0x3:
+ if (encoder->armed)
+ encoder->dir = 2 - state;
+ break;
+
+ case 0x2:
+ encoder->armed = true;
+ break;
+ }
+
+ mutex_unlock(&encoder->access_mutex);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
+{
+ struct rotary_encoder *encoder = dev_id;
+ unsigned int state;
+
+ mutex_lock(&encoder->access_mutex);
+
+ state = rotary_encoder_get_state(encoder);
+
+ if (state & 1) {
+ encoder->dir = ((encoder->last_stable - state + 1) % 4) - 1;
+ } else {
+ if (state != encoder->last_stable) {
+ rotary_encoder_report_event(encoder);
+ encoder->last_stable = state;
+ }
+ }
+
+ mutex_unlock(&encoder->access_mutex);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t rotary_encoder_quarter_period_irq(int irq, void *dev_id)
+{
+ struct rotary_encoder *encoder = dev_id;
+ unsigned int state;
+
+ mutex_lock(&encoder->access_mutex);
+
+ state = rotary_encoder_get_state(encoder);
+
+ if ((encoder->last_stable + 1) % 4 == state)
+ encoder->dir = 1;
+ else if (encoder->last_stable == (state + 1) % 4)
+ encoder->dir = -1;
+ else
+ goto out;
+
+ rotary_encoder_report_event(encoder);
+
+out:
+ encoder->last_stable = state;
+ mutex_unlock(&encoder->access_mutex);
+
+ return IRQ_HANDLED;
+}
+
+static int rotary_encoder_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rotary_encoder *encoder;
+ struct input_dev *input;
+ irq_handler_t handler;
+ u32 steps_per_period;
+ unsigned int i;
+ int err;
+
+ encoder = devm_kzalloc(dev, sizeof(struct rotary_encoder), GFP_KERNEL);
+ if (!encoder)
+ return -ENOMEM;
+
+ mutex_init(&encoder->access_mutex);
+
+ device_property_read_u32(dev, "rotary-encoder,steps", &encoder->steps);
+
+ err = device_property_read_u32(dev, "rotary-encoder,steps-per-period",
+ &steps_per_period);
+ if (err) {
+ /*
+ * The 'half-period' property has been deprecated, you must
+ * use 'steps-per-period' and set an appropriate value, but
+ * we still need to parse it to maintain compatibility. If
+ * neither property is present we fall back to the one step
+ * per period behavior.
+ */
+ steps_per_period = device_property_read_bool(dev,
+ "rotary-encoder,half-period") ? 2 : 1;
+ }
+
+ encoder->rollover =
+ device_property_read_bool(dev, "rotary-encoder,rollover");
+
+ if (!device_property_present(dev, "rotary-encoder,encoding") ||
+ !device_property_match_string(dev, "rotary-encoder,encoding",
+ "gray")) {
+ dev_info(dev, "gray");
+ encoder->encoding = ROTENC_GRAY;
+ } else if (!device_property_match_string(dev, "rotary-encoder,encoding",
+ "binary")) {
+ dev_info(dev, "binary");
+ encoder->encoding = ROTENC_BINARY;
+ } else {
+ dev_err(dev, "unknown encoding setting\n");
+ return -EINVAL;
+ }
+
+ device_property_read_u32(dev, "linux,axis", &encoder->axis);
+ encoder->relative_axis =
+ device_property_read_bool(dev, "rotary-encoder,relative-axis");
+
+ encoder->gpios = devm_gpiod_get_array(dev, NULL, GPIOD_IN);
+ if (IS_ERR(encoder->gpios)) {
+ err = PTR_ERR(encoder->gpios);
+ if (err != -EPROBE_DEFER)
+ dev_err(dev, "unable to get gpios: %d\n", err);
+ return err;
+ }
+ if (encoder->gpios->ndescs < 2) {
+ dev_err(dev, "not enough gpios found\n");
+ return -EINVAL;
+ }
+
+ input = devm_input_allocate_device(dev);
+ if (!input)
+ return -ENOMEM;
+
+ encoder->input = input;
+
+ input->name = pdev->name;
+ input->id.bustype = BUS_HOST;
+ input->dev.parent = dev;
+
+ if (encoder->relative_axis)
+ input_set_capability(input, EV_REL, encoder->axis);
+ else
+ input_set_abs_params(input,
+ encoder->axis, 0, encoder->steps, 0, 1);
+
+ switch (steps_per_period >> (encoder->gpios->ndescs - 2)) {
+ case 4:
+ handler = &rotary_encoder_quarter_period_irq;
+ encoder->last_stable = rotary_encoder_get_state(encoder);
+ break;
+ case 2:
+ handler = &rotary_encoder_half_period_irq;
+ encoder->last_stable = rotary_encoder_get_state(encoder);
+ break;
+ case 1:
+ handler = &rotary_encoder_irq;
+ break;
+ default:
+ dev_err(dev, "'%d' is not a valid steps-per-period value\n",
+ steps_per_period);
+ return -EINVAL;
+ }
+
+ encoder->irq =
+ devm_kcalloc(dev,
+ encoder->gpios->ndescs, sizeof(*encoder->irq),
+ GFP_KERNEL);
+ if (!encoder->irq)
+ return -ENOMEM;
+
+ for (i = 0; i < encoder->gpios->ndescs; ++i) {
+ encoder->irq[i] = gpiod_to_irq(encoder->gpios->desc[i]);
+
+ err = devm_request_threaded_irq(dev, encoder->irq[i],
+ NULL, handler,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ DRV_NAME, encoder);
+ if (err) {
+ dev_err(dev, "unable to request IRQ %d (gpio#%d)\n",
+ encoder->irq[i], i);
+ return err;
+ }
+ }
+
+ err = input_register_device(input);
+ if (err) {
+ dev_err(dev, "failed to register input device\n");
+ return err;
+ }
+
+ device_init_wakeup(dev,
+ device_property_read_bool(dev, "wakeup-source"));
+
+ platform_set_drvdata(pdev, encoder);
+
+ return 0;
+}
+
+static int __maybe_unused rotary_encoder_suspend(struct device *dev)
+{
+ struct rotary_encoder *encoder = dev_get_drvdata(dev);
+ unsigned int i;
+
+ if (device_may_wakeup(dev)) {
+ for (i = 0; i < encoder->gpios->ndescs; ++i)
+ enable_irq_wake(encoder->irq[i]);
+ }
+
+ return 0;
+}
+
+static int __maybe_unused rotary_encoder_resume(struct device *dev)
+{
+ struct rotary_encoder *encoder = dev_get_drvdata(dev);
+ unsigned int i;
+
+ if (device_may_wakeup(dev)) {
+ for (i = 0; i < encoder->gpios->ndescs; ++i)
+ disable_irq_wake(encoder->irq[i]);
+ }
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rotary_encoder_pm_ops,
+ rotary_encoder_suspend, rotary_encoder_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id rotary_encoder_of_match[] = {
+ { .compatible = "rotary-encoder", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rotary_encoder_of_match);
+#endif
+
+static struct platform_driver rotary_encoder_driver = {
+ .probe = rotary_encoder_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .pm = &rotary_encoder_pm_ops,
+ .of_match_table = of_match_ptr(rotary_encoder_of_match),
+ }
+};
+module_platform_driver(rotary_encoder_driver);
+
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DESCRIPTION("GPIO rotary encoder driver");
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>, Johan Hovold");
+MODULE_LICENSE("GPL v2");