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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/iio/adc/envelope-detector.c | |
download | linux-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/iio/adc/envelope-detector.c')
-rw-r--r-- | drivers/iio/adc/envelope-detector.c | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/drivers/iio/adc/envelope-detector.c b/drivers/iio/adc/envelope-detector.c new file mode 100644 index 000000000..e911c25d1 --- /dev/null +++ b/drivers/iio/adc/envelope-detector.c @@ -0,0 +1,408 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for an envelope detector using a DAC and a comparator + * + * Copyright (C) 2016 Axentia Technologies AB + * + * Author: Peter Rosin <peda@axentia.se> + */ + +/* + * The DAC is used to find the peak level of an alternating voltage input + * signal by a binary search using the output of a comparator wired to + * an interrupt pin. Like so: + * _ + * | \ + * input +------>-------|+ \ + * | \ + * .-------. | }---. + * | | | / | + * | dac|-->--|- / | + * | | |_/ | + * | | | + * | | | + * | irq|------<-------' + * | | + * '-------' + */ + +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/mutex.h> +#include <linux/iio/consumer.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/workqueue.h> + +struct envelope { + spinlock_t comp_lock; /* protects comp */ + int comp; + + struct mutex read_lock; /* protects everything else */ + + int comp_irq; + u32 comp_irq_trigger; + u32 comp_irq_trigger_inv; + + struct iio_channel *dac; + struct delayed_work comp_timeout; + + unsigned int comp_interval; + bool invert; + u32 dac_max; + + int high; + int level; + int low; + + struct completion done; +}; + +/* + * The envelope_detector_comp_latch function works together with the compare + * interrupt service routine below (envelope_detector_comp_isr) as a latch + * (one-bit memory) for if the interrupt has triggered since last calling + * this function. + * The ..._comp_isr function disables the interrupt so that the cpu does not + * need to service a possible interrupt flood from the comparator when no-one + * cares anyway, and this ..._comp_latch function reenables them again if + * needed. + */ +static int envelope_detector_comp_latch(struct envelope *env) +{ + int comp; + + spin_lock_irq(&env->comp_lock); + comp = env->comp; + env->comp = 0; + spin_unlock_irq(&env->comp_lock); + + if (!comp) + return 0; + + /* + * The irq was disabled, and is reenabled just now. + * But there might have been a pending irq that + * happened while the irq was disabled that fires + * just as the irq is reenabled. That is not what + * is desired. + */ + enable_irq(env->comp_irq); + + /* So, synchronize this possibly pending irq... */ + synchronize_irq(env->comp_irq); + + /* ...and redo the whole dance. */ + spin_lock_irq(&env->comp_lock); + comp = env->comp; + env->comp = 0; + spin_unlock_irq(&env->comp_lock); + + if (comp) + enable_irq(env->comp_irq); + + return 1; +} + +static irqreturn_t envelope_detector_comp_isr(int irq, void *ctx) +{ + struct envelope *env = ctx; + + spin_lock(&env->comp_lock); + env->comp = 1; + disable_irq_nosync(env->comp_irq); + spin_unlock(&env->comp_lock); + + return IRQ_HANDLED; +} + +static void envelope_detector_setup_compare(struct envelope *env) +{ + int ret; + + /* + * Do a binary search for the peak input level, and stop + * when that level is "trapped" between two adjacent DAC + * values. + * When invert is active, use the midpoint floor so that + * env->level ends up as env->low when the termination + * criteria below is fulfilled, and use the midpoint + * ceiling when invert is not active so that env->level + * ends up as env->high in that case. + */ + env->level = (env->high + env->low + !env->invert) / 2; + + if (env->high == env->low + 1) { + complete(&env->done); + return; + } + + /* Set a "safe" DAC level (if there is such a thing)... */ + ret = iio_write_channel_raw(env->dac, env->invert ? 0 : env->dac_max); + if (ret < 0) + goto err; + + /* ...clear the comparison result... */ + envelope_detector_comp_latch(env); + + /* ...set the real DAC level... */ + ret = iio_write_channel_raw(env->dac, env->level); + if (ret < 0) + goto err; + + /* ...and wait for a bit to see if the latch catches anything. */ + schedule_delayed_work(&env->comp_timeout, + msecs_to_jiffies(env->comp_interval)); + return; + +err: + env->level = ret; + complete(&env->done); +} + +static void envelope_detector_timeout(struct work_struct *work) +{ + struct envelope *env = container_of(work, struct envelope, + comp_timeout.work); + + /* Adjust low/high depending on the latch content... */ + if (!envelope_detector_comp_latch(env) ^ !env->invert) + env->low = env->level; + else + env->high = env->level; + + /* ...and continue the search. */ + envelope_detector_setup_compare(env); +} + +static int envelope_detector_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct envelope *env = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + /* + * When invert is active, start with high=max+1 and low=0 + * since we will end up with the low value when the + * termination criteria is fulfilled (rounding down). And + * start with high=max and low=-1 when invert is not active + * since we will end up with the high value in that case. + * This ensures that the returned value in both cases are + * in the same range as the DAC and is a value that has not + * triggered the comparator. + */ + mutex_lock(&env->read_lock); + env->high = env->dac_max + env->invert; + env->low = -1 + env->invert; + envelope_detector_setup_compare(env); + wait_for_completion(&env->done); + if (env->level < 0) { + ret = env->level; + goto err_unlock; + } + *val = env->invert ? env->dac_max - env->level : env->level; + mutex_unlock(&env->read_lock); + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + return iio_read_channel_scale(env->dac, val, val2); + } + + return -EINVAL; + +err_unlock: + mutex_unlock(&env->read_lock); + return ret; +} + +static ssize_t envelope_show_invert(struct iio_dev *indio_dev, + uintptr_t private, + struct iio_chan_spec const *ch, char *buf) +{ + struct envelope *env = iio_priv(indio_dev); + + return sprintf(buf, "%u\n", env->invert); +} + +static ssize_t envelope_store_invert(struct iio_dev *indio_dev, + uintptr_t private, + struct iio_chan_spec const *ch, + const char *buf, size_t len) +{ + struct envelope *env = iio_priv(indio_dev); + unsigned long invert; + int ret; + u32 trigger; + + ret = kstrtoul(buf, 0, &invert); + if (ret < 0) + return ret; + if (invert > 1) + return -EINVAL; + + trigger = invert ? env->comp_irq_trigger_inv : env->comp_irq_trigger; + + mutex_lock(&env->read_lock); + if (invert != env->invert) + ret = irq_set_irq_type(env->comp_irq, trigger); + if (!ret) { + env->invert = invert; + ret = len; + } + mutex_unlock(&env->read_lock); + + return ret; +} + +static ssize_t envelope_show_comp_interval(struct iio_dev *indio_dev, + uintptr_t private, + struct iio_chan_spec const *ch, + char *buf) +{ + struct envelope *env = iio_priv(indio_dev); + + return sprintf(buf, "%u\n", env->comp_interval); +} + +static ssize_t envelope_store_comp_interval(struct iio_dev *indio_dev, + uintptr_t private, + struct iio_chan_spec const *ch, + const char *buf, size_t len) +{ + struct envelope *env = iio_priv(indio_dev); + unsigned long interval; + int ret; + + ret = kstrtoul(buf, 0, &interval); + if (ret < 0) + return ret; + if (interval > 1000) + return -EINVAL; + + mutex_lock(&env->read_lock); + env->comp_interval = interval; + mutex_unlock(&env->read_lock); + + return len; +} + +static const struct iio_chan_spec_ext_info envelope_detector_ext_info[] = { + { .name = "invert", + .read = envelope_show_invert, + .write = envelope_store_invert, }, + { .name = "compare_interval", + .read = envelope_show_comp_interval, + .write = envelope_store_comp_interval, }, + { /* sentinel */ } +}; + +static const struct iio_chan_spec envelope_detector_iio_channel = { + .type = IIO_ALTVOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) + | BIT(IIO_CHAN_INFO_SCALE), + .ext_info = envelope_detector_ext_info, + .indexed = 1, +}; + +static const struct iio_info envelope_detector_info = { + .read_raw = &envelope_detector_read_raw, +}; + +static int envelope_detector_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct envelope *env; + enum iio_chan_type type; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*env)); + if (!indio_dev) + return -ENOMEM; + + platform_set_drvdata(pdev, indio_dev); + env = iio_priv(indio_dev); + env->comp_interval = 50; /* some sensible default? */ + + spin_lock_init(&env->comp_lock); + mutex_init(&env->read_lock); + init_completion(&env->done); + INIT_DELAYED_WORK(&env->comp_timeout, envelope_detector_timeout); + + indio_dev->name = dev_name(dev); + indio_dev->info = &envelope_detector_info; + indio_dev->channels = &envelope_detector_iio_channel; + indio_dev->num_channels = 1; + + env->dac = devm_iio_channel_get(dev, "dac"); + if (IS_ERR(env->dac)) + return dev_err_probe(dev, PTR_ERR(env->dac), + "failed to get dac input channel\n"); + + env->comp_irq = platform_get_irq_byname(pdev, "comp"); + if (env->comp_irq < 0) + return env->comp_irq; + + ret = devm_request_irq(dev, env->comp_irq, envelope_detector_comp_isr, + 0, "envelope-detector", env); + if (ret) + return dev_err_probe(dev, ret, "failed to request interrupt\n"); + + env->comp_irq_trigger = irq_get_trigger_type(env->comp_irq); + if (env->comp_irq_trigger & IRQF_TRIGGER_RISING) + env->comp_irq_trigger_inv |= IRQF_TRIGGER_FALLING; + if (env->comp_irq_trigger & IRQF_TRIGGER_FALLING) + env->comp_irq_trigger_inv |= IRQF_TRIGGER_RISING; + if (env->comp_irq_trigger & IRQF_TRIGGER_HIGH) + env->comp_irq_trigger_inv |= IRQF_TRIGGER_LOW; + if (env->comp_irq_trigger & IRQF_TRIGGER_LOW) + env->comp_irq_trigger_inv |= IRQF_TRIGGER_HIGH; + + ret = iio_get_channel_type(env->dac, &type); + if (ret < 0) + return ret; + + if (type != IIO_VOLTAGE) { + dev_err(dev, "dac is of the wrong type\n"); + return -EINVAL; + } + + ret = iio_read_max_channel_raw(env->dac, &env->dac_max); + if (ret < 0) { + dev_err(dev, "dac does not indicate its raw maximum value\n"); + return ret; + } + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id envelope_detector_match[] = { + { .compatible = "axentia,tse850-envelope-detector", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, envelope_detector_match); + +static struct platform_driver envelope_detector_driver = { + .probe = envelope_detector_probe, + .driver = { + .name = "iio-envelope-detector", + .of_match_table = envelope_detector_match, + }, +}; +module_platform_driver(envelope_detector_driver); + +MODULE_DESCRIPTION("Envelope detector using a DAC and a comparator"); +MODULE_AUTHOR("Peter Rosin <peda@axentia.se>"); +MODULE_LICENSE("GPL v2"); |