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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/iio/proximity/srf04.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/iio/proximity/srf04.c')
-rw-r--r--drivers/iio/proximity/srf04.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/iio/proximity/srf04.c b/drivers/iio/proximity/srf04.c
new file mode 100644
index 000000000..faf2f806c
--- /dev/null
+++ b/drivers/iio/proximity/srf04.c
@@ -0,0 +1,407 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SRF04: ultrasonic sensor for distance measuring by using GPIOs
+ *
+ * Copyright (c) 2017 Andreas Klinger <ak@it-klinger.de>
+ *
+ * For details about the device see:
+ * https://www.robot-electronics.co.uk/htm/srf04tech.htm
+ *
+ * the measurement cycle as timing diagram looks like:
+ *
+ * +---+
+ * GPIO | |
+ * trig: --+ +------------------------------------------------------
+ * ^ ^
+ * |<->|
+ * udelay(trigger_pulse_us)
+ *
+ * ultra +-+ +-+ +-+
+ * sonic | | | | | |
+ * burst: ---------+ +-+ +-+ +-----------------------------------------
+ * .
+ * ultra . +-+ +-+ +-+
+ * sonic . | | | | | |
+ * echo: ----------------------------------+ +-+ +-+ +----------------
+ * . .
+ * +------------------------+
+ * GPIO | |
+ * echo: -------------------+ +---------------
+ * ^ ^
+ * interrupt interrupt
+ * (ts_rising) (ts_falling)
+ * |<---------------------->|
+ * pulse time measured
+ * --> one round trip of ultra sonic waves
+ */
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+struct srf04_cfg {
+ unsigned long trigger_pulse_us;
+};
+
+struct srf04_data {
+ struct device *dev;
+ struct gpio_desc *gpiod_trig;
+ struct gpio_desc *gpiod_echo;
+ struct gpio_desc *gpiod_power;
+ struct mutex lock;
+ int irqnr;
+ ktime_t ts_rising;
+ ktime_t ts_falling;
+ struct completion rising;
+ struct completion falling;
+ const struct srf04_cfg *cfg;
+ int startup_time_ms;
+};
+
+static const struct srf04_cfg srf04_cfg = {
+ .trigger_pulse_us = 10,
+};
+
+static const struct srf04_cfg mb_lv_cfg = {
+ .trigger_pulse_us = 20,
+};
+
+static irqreturn_t srf04_handle_irq(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct srf04_data *data = iio_priv(indio_dev);
+ ktime_t now = ktime_get();
+
+ if (gpiod_get_value(data->gpiod_echo)) {
+ data->ts_rising = now;
+ complete(&data->rising);
+ } else {
+ data->ts_falling = now;
+ complete(&data->falling);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int srf04_read(struct srf04_data *data)
+{
+ int ret;
+ ktime_t ktime_dt;
+ u64 dt_ns;
+ u32 time_ns, distance_mm;
+
+ if (data->gpiod_power) {
+ ret = pm_runtime_resume_and_get(data->dev);
+ if (ret < 0)
+ return ret;
+ }
+ /*
+ * just one read-echo-cycle can take place at a time
+ * ==> lock against concurrent reading calls
+ */
+ mutex_lock(&data->lock);
+
+ reinit_completion(&data->rising);
+ reinit_completion(&data->falling);
+
+ gpiod_set_value(data->gpiod_trig, 1);
+ udelay(data->cfg->trigger_pulse_us);
+ gpiod_set_value(data->gpiod_trig, 0);
+
+ if (data->gpiod_power) {
+ pm_runtime_mark_last_busy(data->dev);
+ pm_runtime_put_autosuspend(data->dev);
+ }
+
+ /* it should not take more than 20 ms until echo is rising */
+ ret = wait_for_completion_killable_timeout(&data->rising, HZ/50);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ } else if (ret == 0) {
+ mutex_unlock(&data->lock);
+ return -ETIMEDOUT;
+ }
+
+ /* it cannot take more than 50 ms until echo is falling */
+ ret = wait_for_completion_killable_timeout(&data->falling, HZ/20);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ } else if (ret == 0) {
+ mutex_unlock(&data->lock);
+ return -ETIMEDOUT;
+ }
+
+ ktime_dt = ktime_sub(data->ts_falling, data->ts_rising);
+
+ mutex_unlock(&data->lock);
+
+ dt_ns = ktime_to_ns(ktime_dt);
+ /*
+ * measuring more than 6,45 meters is beyond the capabilities of
+ * the supported sensors
+ * ==> filter out invalid results for not measuring echos of
+ * another us sensor
+ *
+ * formula:
+ * distance 6,45 * 2 m
+ * time = ---------- = ------------ = 40438871 ns
+ * speed 319 m/s
+ *
+ * using a minimum speed at -20 °C of 319 m/s
+ */
+ if (dt_ns > 40438871)
+ return -EIO;
+
+ time_ns = dt_ns;
+
+ /*
+ * the speed as function of the temperature is approximately:
+ *
+ * speed = 331,5 + 0,6 * Temp
+ * with Temp in °C
+ * and speed in m/s
+ *
+ * use 343,5 m/s as ultrasonic speed at 20 °C here in absence of the
+ * temperature
+ *
+ * therefore:
+ * time 343,5 time * 106
+ * distance = ------ * ------- = ------------
+ * 10^6 2 617176
+ * with time in ns
+ * and distance in mm (one way)
+ *
+ * because we limit to 6,45 meters the multiplication with 106 just
+ * fits into 32 bit
+ */
+ distance_mm = time_ns * 106 / 617176;
+
+ return distance_mm;
+}
+
+static int srf04_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val,
+ int *val2, long info)
+{
+ struct srf04_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (channel->type != IIO_DISTANCE)
+ return -EINVAL;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ ret = srf04_read(data);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /*
+ * theoretical maximum resolution is 3 mm
+ * 1 LSB is 1 mm
+ */
+ *val = 0;
+ *val2 = 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info srf04_iio_info = {
+ .read_raw = srf04_read_raw,
+};
+
+static const struct iio_chan_spec srf04_chan_spec[] = {
+ {
+ .type = IIO_DISTANCE,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ },
+};
+
+static const struct of_device_id of_srf04_match[] = {
+ { .compatible = "devantech,srf04", .data = &srf04_cfg },
+ { .compatible = "maxbotix,mb1000", .data = &mb_lv_cfg },
+ { .compatible = "maxbotix,mb1010", .data = &mb_lv_cfg },
+ { .compatible = "maxbotix,mb1020", .data = &mb_lv_cfg },
+ { .compatible = "maxbotix,mb1030", .data = &mb_lv_cfg },
+ { .compatible = "maxbotix,mb1040", .data = &mb_lv_cfg },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_srf04_match);
+
+static int srf04_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct srf04_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(struct srf04_data));
+ if (!indio_dev) {
+ dev_err(dev, "failed to allocate IIO device\n");
+ return -ENOMEM;
+ }
+
+ data = iio_priv(indio_dev);
+ data->dev = dev;
+ data->cfg = device_get_match_data(dev);
+
+ mutex_init(&data->lock);
+ init_completion(&data->rising);
+ init_completion(&data->falling);
+
+ data->gpiod_trig = devm_gpiod_get(dev, "trig", GPIOD_OUT_LOW);
+ if (IS_ERR(data->gpiod_trig)) {
+ dev_err(dev, "failed to get trig-gpios: err=%ld\n",
+ PTR_ERR(data->gpiod_trig));
+ return PTR_ERR(data->gpiod_trig);
+ }
+
+ data->gpiod_echo = devm_gpiod_get(dev, "echo", GPIOD_IN);
+ if (IS_ERR(data->gpiod_echo)) {
+ dev_err(dev, "failed to get echo-gpios: err=%ld\n",
+ PTR_ERR(data->gpiod_echo));
+ return PTR_ERR(data->gpiod_echo);
+ }
+
+ data->gpiod_power = devm_gpiod_get_optional(dev, "power",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(data->gpiod_power)) {
+ dev_err(dev, "failed to get power-gpios: err=%ld\n",
+ PTR_ERR(data->gpiod_power));
+ return PTR_ERR(data->gpiod_power);
+ }
+ if (data->gpiod_power) {
+ data->startup_time_ms = 100;
+ device_property_read_u32(dev, "startup-time-ms", &data->startup_time_ms);
+ dev_dbg(dev, "using power gpio: startup-time-ms=%d\n",
+ data->startup_time_ms);
+ }
+
+ if (gpiod_cansleep(data->gpiod_echo)) {
+ dev_err(data->dev, "cansleep-GPIOs not supported\n");
+ return -ENODEV;
+ }
+
+ data->irqnr = gpiod_to_irq(data->gpiod_echo);
+ if (data->irqnr < 0) {
+ dev_err(data->dev, "gpiod_to_irq: %d\n", data->irqnr);
+ return data->irqnr;
+ }
+
+ ret = devm_request_irq(dev, data->irqnr, srf04_handle_irq,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+ pdev->name, indio_dev);
+ if (ret < 0) {
+ dev_err(data->dev, "request_irq: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ indio_dev->name = "srf04";
+ indio_dev->info = &srf04_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = srf04_chan_spec;
+ indio_dev->num_channels = ARRAY_SIZE(srf04_chan_spec);
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(data->dev, "iio_device_register: %d\n", ret);
+ return ret;
+ }
+
+ if (data->gpiod_power) {
+ pm_runtime_set_autosuspend_delay(data->dev, 1000);
+ pm_runtime_use_autosuspend(data->dev);
+
+ ret = pm_runtime_set_active(data->dev);
+ if (ret) {
+ dev_err(data->dev, "pm_runtime_set_active: %d\n", ret);
+ iio_device_unregister(indio_dev);
+ }
+
+ pm_runtime_enable(data->dev);
+ pm_runtime_idle(data->dev);
+ }
+
+ return ret;
+}
+
+static int srf04_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ if (data->gpiod_power) {
+ pm_runtime_disable(data->dev);
+ pm_runtime_set_suspended(data->dev);
+ }
+
+ return 0;
+}
+
+static int srf04_pm_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ gpiod_set_value(data->gpiod_power, 0);
+
+ return 0;
+}
+
+static int srf04_pm_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct srf04_data *data = iio_priv(indio_dev);
+
+ gpiod_set_value(data->gpiod_power, 1);
+ msleep(data->startup_time_ms);
+
+ return 0;
+}
+
+static const struct dev_pm_ops srf04_pm_ops = {
+ RUNTIME_PM_OPS(srf04_pm_runtime_suspend,
+ srf04_pm_runtime_resume, NULL)
+};
+
+static struct platform_driver srf04_driver = {
+ .probe = srf04_probe,
+ .remove = srf04_remove,
+ .driver = {
+ .name = "srf04-gpio",
+ .of_match_table = of_srf04_match,
+ .pm = pm_ptr(&srf04_pm_ops),
+ },
+};
+
+module_platform_driver(srf04_driver);
+
+MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
+MODULE_DESCRIPTION("SRF04 ultrasonic sensor for distance measuring using GPIOs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:srf04");