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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/pwm/core.c
downloadlinux-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/pwm/core.c')
-rw-r--r--drivers/pwm/core.c1196
1 files changed, 1196 insertions, 0 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
new file mode 100644
index 000000000..e01147f66
--- /dev/null
+++ b/drivers/pwm/core.c
@@ -0,0 +1,1196 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Generic pwmlib implementation
+ *
+ * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de>
+ * Copyright (C) 2011-2012 Avionic Design GmbH
+ */
+
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/pwm.h>
+#include <linux/radix-tree.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include <dt-bindings/pwm/pwm.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/pwm.h>
+
+#define MAX_PWMS 1024
+
+static DEFINE_MUTEX(pwm_lookup_lock);
+static LIST_HEAD(pwm_lookup_list);
+
+/* protects access to pwm_chips, allocated_pwms, and pwm_tree */
+static DEFINE_MUTEX(pwm_lock);
+
+static LIST_HEAD(pwm_chips);
+static DECLARE_BITMAP(allocated_pwms, MAX_PWMS);
+static RADIX_TREE(pwm_tree, GFP_KERNEL);
+
+static struct pwm_device *pwm_to_device(unsigned int pwm)
+{
+ return radix_tree_lookup(&pwm_tree, pwm);
+}
+
+/* Called with pwm_lock held */
+static int alloc_pwms(unsigned int count)
+{
+ unsigned int start;
+
+ start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, 0,
+ count, 0);
+
+ if (start + count > MAX_PWMS)
+ return -ENOSPC;
+
+ bitmap_set(allocated_pwms, start, count);
+
+ return start;
+}
+
+/* Called with pwm_lock held */
+static void free_pwms(struct pwm_chip *chip)
+{
+ unsigned int i;
+
+ for (i = 0; i < chip->npwm; i++) {
+ struct pwm_device *pwm = &chip->pwms[i];
+
+ radix_tree_delete(&pwm_tree, pwm->pwm);
+ }
+
+ bitmap_clear(allocated_pwms, chip->base, chip->npwm);
+
+ kfree(chip->pwms);
+ chip->pwms = NULL;
+}
+
+static struct pwm_chip *pwmchip_find_by_name(const char *name)
+{
+ struct pwm_chip *chip;
+
+ if (!name)
+ return NULL;
+
+ mutex_lock(&pwm_lock);
+
+ list_for_each_entry(chip, &pwm_chips, list) {
+ const char *chip_name = dev_name(chip->dev);
+
+ if (chip_name && strcmp(chip_name, name) == 0) {
+ mutex_unlock(&pwm_lock);
+ return chip;
+ }
+ }
+
+ mutex_unlock(&pwm_lock);
+
+ return NULL;
+}
+
+static int pwm_device_request(struct pwm_device *pwm, const char *label)
+{
+ int err;
+
+ if (test_bit(PWMF_REQUESTED, &pwm->flags))
+ return -EBUSY;
+
+ if (!try_module_get(pwm->chip->ops->owner))
+ return -ENODEV;
+
+ if (pwm->chip->ops->request) {
+ err = pwm->chip->ops->request(pwm->chip, pwm);
+ if (err) {
+ module_put(pwm->chip->ops->owner);
+ return err;
+ }
+ }
+
+ if (pwm->chip->ops->get_state) {
+ struct pwm_state state;
+
+ err = pwm->chip->ops->get_state(pwm->chip, pwm, &state);
+ trace_pwm_get(pwm, &state, err);
+
+ if (!err)
+ pwm->state = state;
+
+ if (IS_ENABLED(CONFIG_PWM_DEBUG))
+ pwm->last = pwm->state;
+ }
+
+ set_bit(PWMF_REQUESTED, &pwm->flags);
+ pwm->label = label;
+
+ return 0;
+}
+
+struct pwm_device *
+of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
+{
+ struct pwm_device *pwm;
+
+ if (pc->of_pwm_n_cells < 2)
+ return ERR_PTR(-EINVAL);
+
+ /* flags in the third cell are optional */
+ if (args->args_count < 2)
+ return ERR_PTR(-EINVAL);
+
+ if (args->args[0] >= pc->npwm)
+ return ERR_PTR(-EINVAL);
+
+ pwm = pwm_request_from_chip(pc, args->args[0], NULL);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ pwm->args.period = args->args[1];
+ pwm->args.polarity = PWM_POLARITY_NORMAL;
+
+ if (pc->of_pwm_n_cells >= 3) {
+ if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED)
+ pwm->args.polarity = PWM_POLARITY_INVERSED;
+ }
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags);
+
+struct pwm_device *
+of_pwm_single_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
+{
+ struct pwm_device *pwm;
+
+ if (pc->of_pwm_n_cells < 1)
+ return ERR_PTR(-EINVAL);
+
+ /* validate that one cell is specified, optionally with flags */
+ if (args->args_count != 1 && args->args_count != 2)
+ return ERR_PTR(-EINVAL);
+
+ pwm = pwm_request_from_chip(pc, 0, NULL);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ pwm->args.period = args->args[0];
+ pwm->args.polarity = PWM_POLARITY_NORMAL;
+
+ if (args->args_count == 2 && args->args[2] & PWM_POLARITY_INVERTED)
+ pwm->args.polarity = PWM_POLARITY_INVERSED;
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(of_pwm_single_xlate);
+
+static void of_pwmchip_add(struct pwm_chip *chip)
+{
+ if (!chip->dev || !chip->dev->of_node)
+ return;
+
+ if (!chip->of_xlate) {
+ u32 pwm_cells;
+
+ if (of_property_read_u32(chip->dev->of_node, "#pwm-cells",
+ &pwm_cells))
+ pwm_cells = 2;
+
+ chip->of_xlate = of_pwm_xlate_with_flags;
+ chip->of_pwm_n_cells = pwm_cells;
+ }
+
+ of_node_get(chip->dev->of_node);
+}
+
+static void of_pwmchip_remove(struct pwm_chip *chip)
+{
+ if (chip->dev)
+ of_node_put(chip->dev->of_node);
+}
+
+/**
+ * pwm_set_chip_data() - set private chip data for a PWM
+ * @pwm: PWM device
+ * @data: pointer to chip-specific data
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+int pwm_set_chip_data(struct pwm_device *pwm, void *data)
+{
+ if (!pwm)
+ return -EINVAL;
+
+ pwm->chip_data = data;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pwm_set_chip_data);
+
+/**
+ * pwm_get_chip_data() - get private chip data for a PWM
+ * @pwm: PWM device
+ *
+ * Returns: A pointer to the chip-private data for the PWM device.
+ */
+void *pwm_get_chip_data(struct pwm_device *pwm)
+{
+ return pwm ? pwm->chip_data : NULL;
+}
+EXPORT_SYMBOL_GPL(pwm_get_chip_data);
+
+static bool pwm_ops_check(const struct pwm_chip *chip)
+{
+ const struct pwm_ops *ops = chip->ops;
+
+ if (!ops->apply)
+ return false;
+
+ if (IS_ENABLED(CONFIG_PWM_DEBUG) && !ops->get_state)
+ dev_warn(chip->dev,
+ "Please implement the .get_state() callback\n");
+
+ return true;
+}
+
+/**
+ * pwmchip_add() - register a new PWM chip
+ * @chip: the PWM chip to add
+ *
+ * Register a new PWM chip.
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+int pwmchip_add(struct pwm_chip *chip)
+{
+ struct pwm_device *pwm;
+ unsigned int i;
+ int ret;
+
+ if (!chip || !chip->dev || !chip->ops || !chip->npwm)
+ return -EINVAL;
+
+ if (!pwm_ops_check(chip))
+ return -EINVAL;
+
+ chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL);
+ if (!chip->pwms)
+ return -ENOMEM;
+
+ mutex_lock(&pwm_lock);
+
+ ret = alloc_pwms(chip->npwm);
+ if (ret < 0) {
+ mutex_unlock(&pwm_lock);
+ kfree(chip->pwms);
+ return ret;
+ }
+
+ chip->base = ret;
+
+ for (i = 0; i < chip->npwm; i++) {
+ pwm = &chip->pwms[i];
+
+ pwm->chip = chip;
+ pwm->pwm = chip->base + i;
+ pwm->hwpwm = i;
+
+ radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
+ }
+
+ list_add(&chip->list, &pwm_chips);
+
+ mutex_unlock(&pwm_lock);
+
+ if (IS_ENABLED(CONFIG_OF))
+ of_pwmchip_add(chip);
+
+ pwmchip_sysfs_export(chip);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pwmchip_add);
+
+/**
+ * pwmchip_remove() - remove a PWM chip
+ * @chip: the PWM chip to remove
+ *
+ * Removes a PWM chip. This function may return busy if the PWM chip provides
+ * a PWM device that is still requested.
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+void pwmchip_remove(struct pwm_chip *chip)
+{
+ pwmchip_sysfs_unexport(chip);
+
+ mutex_lock(&pwm_lock);
+
+ list_del_init(&chip->list);
+
+ if (IS_ENABLED(CONFIG_OF))
+ of_pwmchip_remove(chip);
+
+ free_pwms(chip);
+
+ mutex_unlock(&pwm_lock);
+}
+EXPORT_SYMBOL_GPL(pwmchip_remove);
+
+static void devm_pwmchip_remove(void *data)
+{
+ struct pwm_chip *chip = data;
+
+ pwmchip_remove(chip);
+}
+
+int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip)
+{
+ int ret;
+
+ ret = pwmchip_add(chip);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev, devm_pwmchip_remove, chip);
+}
+EXPORT_SYMBOL_GPL(devm_pwmchip_add);
+
+/**
+ * pwm_request() - request a PWM device
+ * @pwm: global PWM device index
+ * @label: PWM device label
+ *
+ * This function is deprecated, use pwm_get() instead.
+ *
+ * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on
+ * failure.
+ */
+struct pwm_device *pwm_request(int pwm, const char *label)
+{
+ struct pwm_device *dev;
+ int err;
+
+ if (pwm < 0 || pwm >= MAX_PWMS)
+ return ERR_PTR(-EINVAL);
+
+ mutex_lock(&pwm_lock);
+
+ dev = pwm_to_device(pwm);
+ if (!dev) {
+ dev = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ err = pwm_device_request(dev, label);
+ if (err < 0)
+ dev = ERR_PTR(err);
+
+out:
+ mutex_unlock(&pwm_lock);
+
+ return dev;
+}
+EXPORT_SYMBOL_GPL(pwm_request);
+
+/**
+ * pwm_request_from_chip() - request a PWM device relative to a PWM chip
+ * @chip: PWM chip
+ * @index: per-chip index of the PWM to request
+ * @label: a literal description string of this PWM
+ *
+ * Returns: A pointer to the PWM device at the given index of the given PWM
+ * chip. A negative error code is returned if the index is not valid for the
+ * specified PWM chip or if the PWM device cannot be requested.
+ */
+struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
+ unsigned int index,
+ const char *label)
+{
+ struct pwm_device *pwm;
+ int err;
+
+ if (!chip || index >= chip->npwm)
+ return ERR_PTR(-EINVAL);
+
+ mutex_lock(&pwm_lock);
+ pwm = &chip->pwms[index];
+
+ err = pwm_device_request(pwm, label);
+ if (err < 0)
+ pwm = ERR_PTR(err);
+
+ mutex_unlock(&pwm_lock);
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(pwm_request_from_chip);
+
+/**
+ * pwm_free() - free a PWM device
+ * @pwm: PWM device
+ *
+ * This function is deprecated, use pwm_put() instead.
+ */
+void pwm_free(struct pwm_device *pwm)
+{
+ pwm_put(pwm);
+}
+EXPORT_SYMBOL_GPL(pwm_free);
+
+static void pwm_apply_state_debug(struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct pwm_state *last = &pwm->last;
+ struct pwm_chip *chip = pwm->chip;
+ struct pwm_state s1, s2;
+ int err;
+
+ if (!IS_ENABLED(CONFIG_PWM_DEBUG))
+ return;
+
+ /* No reasonable diagnosis possible without .get_state() */
+ if (!chip->ops->get_state)
+ return;
+
+ /*
+ * *state was just applied. Read out the hardware state and do some
+ * checks.
+ */
+
+ err = chip->ops->get_state(chip, pwm, &s1);
+ trace_pwm_get(pwm, &s1, err);
+ if (err)
+ /* If that failed there isn't much to debug */
+ return;
+
+ /*
+ * The lowlevel driver either ignored .polarity (which is a bug) or as
+ * best effort inverted .polarity and fixed .duty_cycle respectively.
+ * Undo this inversion and fixup for further tests.
+ */
+ if (s1.enabled && s1.polarity != state->polarity) {
+ s2.polarity = state->polarity;
+ s2.duty_cycle = s1.period - s1.duty_cycle;
+ s2.period = s1.period;
+ s2.enabled = s1.enabled;
+ } else {
+ s2 = s1;
+ }
+
+ if (s2.polarity != state->polarity &&
+ state->duty_cycle < state->period)
+ dev_warn(chip->dev, ".apply ignored .polarity\n");
+
+ if (state->enabled &&
+ last->polarity == state->polarity &&
+ last->period > s2.period &&
+ last->period <= state->period)
+ dev_warn(chip->dev,
+ ".apply didn't pick the best available period (requested: %llu, applied: %llu, possible: %llu)\n",
+ state->period, s2.period, last->period);
+
+ if (state->enabled && state->period < s2.period)
+ dev_warn(chip->dev,
+ ".apply is supposed to round down period (requested: %llu, applied: %llu)\n",
+ state->period, s2.period);
+
+ if (state->enabled &&
+ last->polarity == state->polarity &&
+ last->period == s2.period &&
+ last->duty_cycle > s2.duty_cycle &&
+ last->duty_cycle <= state->duty_cycle)
+ dev_warn(chip->dev,
+ ".apply didn't pick the best available duty cycle (requested: %llu/%llu, applied: %llu/%llu, possible: %llu/%llu)\n",
+ state->duty_cycle, state->period,
+ s2.duty_cycle, s2.period,
+ last->duty_cycle, last->period);
+
+ if (state->enabled && state->duty_cycle < s2.duty_cycle)
+ dev_warn(chip->dev,
+ ".apply is supposed to round down duty_cycle (requested: %llu/%llu, applied: %llu/%llu)\n",
+ state->duty_cycle, state->period,
+ s2.duty_cycle, s2.period);
+
+ if (!state->enabled && s2.enabled && s2.duty_cycle > 0)
+ dev_warn(chip->dev,
+ "requested disabled, but yielded enabled with duty > 0\n");
+
+ /* reapply the state that the driver reported being configured. */
+ err = chip->ops->apply(chip, pwm, &s1);
+ trace_pwm_apply(pwm, &s1, err);
+ if (err) {
+ *last = s1;
+ dev_err(chip->dev, "failed to reapply current setting\n");
+ return;
+ }
+
+ err = chip->ops->get_state(chip, pwm, last);
+ trace_pwm_get(pwm, last, err);
+ if (err)
+ return;
+
+ /* reapplication of the current state should give an exact match */
+ if (s1.enabled != last->enabled ||
+ s1.polarity != last->polarity ||
+ (s1.enabled && s1.period != last->period) ||
+ (s1.enabled && s1.duty_cycle != last->duty_cycle)) {
+ dev_err(chip->dev,
+ ".apply is not idempotent (ena=%d pol=%d %llu/%llu) -> (ena=%d pol=%d %llu/%llu)\n",
+ s1.enabled, s1.polarity, s1.duty_cycle, s1.period,
+ last->enabled, last->polarity, last->duty_cycle,
+ last->period);
+ }
+}
+
+/**
+ * pwm_apply_state() - atomically apply a new state to a PWM device
+ * @pwm: PWM device
+ * @state: new state to apply
+ */
+int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
+{
+ struct pwm_chip *chip;
+ int err;
+
+ /*
+ * Some lowlevel driver's implementations of .apply() make use of
+ * mutexes, also with some drivers only returning when the new
+ * configuration is active calling pwm_apply_state() from atomic context
+ * is a bad idea. So make it explicit that calling this function might
+ * sleep.
+ */
+ might_sleep();
+
+ if (!pwm || !state || !state->period ||
+ state->duty_cycle > state->period)
+ return -EINVAL;
+
+ chip = pwm->chip;
+
+ if (state->period == pwm->state.period &&
+ state->duty_cycle == pwm->state.duty_cycle &&
+ state->polarity == pwm->state.polarity &&
+ state->enabled == pwm->state.enabled &&
+ state->usage_power == pwm->state.usage_power)
+ return 0;
+
+ err = chip->ops->apply(chip, pwm, state);
+ trace_pwm_apply(pwm, state, err);
+ if (err)
+ return err;
+
+ pwm->state = *state;
+
+ /*
+ * only do this after pwm->state was applied as some
+ * implementations of .get_state depend on this
+ */
+ pwm_apply_state_debug(pwm, state);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pwm_apply_state);
+
+/**
+ * pwm_capture() - capture and report a PWM signal
+ * @pwm: PWM device
+ * @result: structure to fill with capture result
+ * @timeout: time to wait, in milliseconds, before giving up on capture
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result,
+ unsigned long timeout)
+{
+ int err;
+
+ if (!pwm || !pwm->chip->ops)
+ return -EINVAL;
+
+ if (!pwm->chip->ops->capture)
+ return -ENOSYS;
+
+ mutex_lock(&pwm_lock);
+ err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout);
+ mutex_unlock(&pwm_lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(pwm_capture);
+
+/**
+ * pwm_adjust_config() - adjust the current PWM config to the PWM arguments
+ * @pwm: PWM device
+ *
+ * This function will adjust the PWM config to the PWM arguments provided
+ * by the DT or PWM lookup table. This is particularly useful to adapt
+ * the bootloader config to the Linux one.
+ */
+int pwm_adjust_config(struct pwm_device *pwm)
+{
+ struct pwm_state state;
+ struct pwm_args pargs;
+
+ pwm_get_args(pwm, &pargs);
+ pwm_get_state(pwm, &state);
+
+ /*
+ * If the current period is zero it means that either the PWM driver
+ * does not support initial state retrieval or the PWM has not yet
+ * been configured.
+ *
+ * In either case, we setup the new period and polarity, and assign a
+ * duty cycle of 0.
+ */
+ if (!state.period) {
+ state.duty_cycle = 0;
+ state.period = pargs.period;
+ state.polarity = pargs.polarity;
+
+ return pwm_apply_state(pwm, &state);
+ }
+
+ /*
+ * Adjust the PWM duty cycle/period based on the period value provided
+ * in PWM args.
+ */
+ if (pargs.period != state.period) {
+ u64 dutycycle = (u64)state.duty_cycle * pargs.period;
+
+ do_div(dutycycle, state.period);
+ state.duty_cycle = dutycycle;
+ state.period = pargs.period;
+ }
+
+ /*
+ * If the polarity changed, we should also change the duty cycle.
+ */
+ if (pargs.polarity != state.polarity) {
+ state.polarity = pargs.polarity;
+ state.duty_cycle = state.period - state.duty_cycle;
+ }
+
+ return pwm_apply_state(pwm, &state);
+}
+EXPORT_SYMBOL_GPL(pwm_adjust_config);
+
+static struct pwm_chip *fwnode_to_pwmchip(struct fwnode_handle *fwnode)
+{
+ struct pwm_chip *chip;
+
+ mutex_lock(&pwm_lock);
+
+ list_for_each_entry(chip, &pwm_chips, list)
+ if (chip->dev && device_match_fwnode(chip->dev, fwnode)) {
+ mutex_unlock(&pwm_lock);
+ return chip;
+ }
+
+ mutex_unlock(&pwm_lock);
+
+ return ERR_PTR(-EPROBE_DEFER);
+}
+
+static struct device_link *pwm_device_link_add(struct device *dev,
+ struct pwm_device *pwm)
+{
+ struct device_link *dl;
+
+ if (!dev) {
+ /*
+ * No device for the PWM consumer has been provided. It may
+ * impact the PM sequence ordering: the PWM supplier may get
+ * suspended before the consumer.
+ */
+ dev_warn(pwm->chip->dev,
+ "No consumer device specified to create a link to\n");
+ return NULL;
+ }
+
+ dl = device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
+ if (!dl) {
+ dev_err(dev, "failed to create device link to %s\n",
+ dev_name(pwm->chip->dev));
+ return ERR_PTR(-EINVAL);
+ }
+
+ return dl;
+}
+
+/**
+ * of_pwm_get() - request a PWM via the PWM framework
+ * @dev: device for PWM consumer
+ * @np: device node to get the PWM from
+ * @con_id: consumer name
+ *
+ * Returns the PWM device parsed from the phandle and index specified in the
+ * "pwms" property of a device tree node or a negative error-code on failure.
+ * Values parsed from the device tree are stored in the returned PWM device
+ * object.
+ *
+ * If con_id is NULL, the first PWM device listed in the "pwms" property will
+ * be requested. Otherwise the "pwm-names" property is used to do a reverse
+ * lookup of the PWM index. This also means that the "pwm-names" property
+ * becomes mandatory for devices that look up the PWM device via the con_id
+ * parameter.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+static struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np,
+ const char *con_id)
+{
+ struct pwm_device *pwm = NULL;
+ struct of_phandle_args args;
+ struct device_link *dl;
+ struct pwm_chip *pc;
+ int index = 0;
+ int err;
+
+ if (con_id) {
+ index = of_property_match_string(np, "pwm-names", con_id);
+ if (index < 0)
+ return ERR_PTR(index);
+ }
+
+ err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index,
+ &args);
+ if (err) {
+ pr_err("%s(): can't parse \"pwms\" property\n", __func__);
+ return ERR_PTR(err);
+ }
+
+ pc = fwnode_to_pwmchip(of_fwnode_handle(args.np));
+ if (IS_ERR(pc)) {
+ if (PTR_ERR(pc) != -EPROBE_DEFER)
+ pr_err("%s(): PWM chip not found\n", __func__);
+
+ pwm = ERR_CAST(pc);
+ goto put;
+ }
+
+ pwm = pc->of_xlate(pc, &args);
+ if (IS_ERR(pwm))
+ goto put;
+
+ dl = pwm_device_link_add(dev, pwm);
+ if (IS_ERR(dl)) {
+ /* of_xlate ended up calling pwm_request_from_chip() */
+ pwm_free(pwm);
+ pwm = ERR_CAST(dl);
+ goto put;
+ }
+
+ /*
+ * If a consumer name was not given, try to look it up from the
+ * "pwm-names" property if it exists. Otherwise use the name of
+ * the user device node.
+ */
+ if (!con_id) {
+ err = of_property_read_string_index(np, "pwm-names", index,
+ &con_id);
+ if (err < 0)
+ con_id = np->name;
+ }
+
+ pwm->label = con_id;
+
+put:
+ of_node_put(args.np);
+
+ return pwm;
+}
+
+/**
+ * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI
+ * @fwnode: firmware node to get the "pwms" property from
+ *
+ * Returns the PWM device parsed from the fwnode and index specified in the
+ * "pwms" property or a negative error-code on failure.
+ * Values parsed from the device tree are stored in the returned PWM device
+ * object.
+ *
+ * This is analogous to of_pwm_get() except con_id is not yet supported.
+ * ACPI entries must look like
+ * Package () {"pwms", Package ()
+ * { <PWM device reference>, <PWM index>, <PWM period> [, <PWM flags>]}}
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+static struct pwm_device *acpi_pwm_get(const struct fwnode_handle *fwnode)
+{
+ struct pwm_device *pwm;
+ struct fwnode_reference_args args;
+ struct pwm_chip *chip;
+ int ret;
+
+ memset(&args, 0, sizeof(args));
+
+ ret = __acpi_node_get_property_reference(fwnode, "pwms", 0, 3, &args);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ if (args.nargs < 2)
+ return ERR_PTR(-EPROTO);
+
+ chip = fwnode_to_pwmchip(args.fwnode);
+ if (IS_ERR(chip))
+ return ERR_CAST(chip);
+
+ pwm = pwm_request_from_chip(chip, args.args[0], NULL);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ pwm->args.period = args.args[1];
+ pwm->args.polarity = PWM_POLARITY_NORMAL;
+
+ if (args.nargs > 2 && args.args[2] & PWM_POLARITY_INVERTED)
+ pwm->args.polarity = PWM_POLARITY_INVERSED;
+
+ return pwm;
+}
+
+/**
+ * pwm_add_table() - register PWM device consumers
+ * @table: array of consumers to register
+ * @num: number of consumers in table
+ */
+void pwm_add_table(struct pwm_lookup *table, size_t num)
+{
+ mutex_lock(&pwm_lookup_lock);
+
+ while (num--) {
+ list_add_tail(&table->list, &pwm_lookup_list);
+ table++;
+ }
+
+ mutex_unlock(&pwm_lookup_lock);
+}
+
+/**
+ * pwm_remove_table() - unregister PWM device consumers
+ * @table: array of consumers to unregister
+ * @num: number of consumers in table
+ */
+void pwm_remove_table(struct pwm_lookup *table, size_t num)
+{
+ mutex_lock(&pwm_lookup_lock);
+
+ while (num--) {
+ list_del(&table->list);
+ table++;
+ }
+
+ mutex_unlock(&pwm_lookup_lock);
+}
+
+/**
+ * pwm_get() - look up and request a PWM device
+ * @dev: device for PWM consumer
+ * @con_id: consumer name
+ *
+ * Lookup is first attempted using DT. If the device was not instantiated from
+ * a device tree, a PWM chip and a relative index is looked up via a table
+ * supplied by board setup code (see pwm_add_table()).
+ *
+ * Once a PWM chip has been found the specified PWM device will be requested
+ * and is ready to be used.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+struct pwm_device *pwm_get(struct device *dev, const char *con_id)
+{
+ const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL;
+ const char *dev_id = dev ? dev_name(dev) : NULL;
+ struct pwm_device *pwm;
+ struct pwm_chip *chip;
+ struct device_link *dl;
+ unsigned int best = 0;
+ struct pwm_lookup *p, *chosen = NULL;
+ unsigned int match;
+ int err;
+
+ /* look up via DT first */
+ if (is_of_node(fwnode))
+ return of_pwm_get(dev, to_of_node(fwnode), con_id);
+
+ /* then lookup via ACPI */
+ if (is_acpi_node(fwnode)) {
+ pwm = acpi_pwm_get(fwnode);
+ if (!IS_ERR(pwm) || PTR_ERR(pwm) != -ENOENT)
+ return pwm;
+ }
+
+ /*
+ * We look up the provider in the static table typically provided by
+ * board setup code. We first try to lookup the consumer device by
+ * name. If the consumer device was passed in as NULL or if no match
+ * was found, we try to find the consumer by directly looking it up
+ * by name.
+ *
+ * If a match is found, the provider PWM chip is looked up by name
+ * and a PWM device is requested using the PWM device per-chip index.
+ *
+ * The lookup algorithm was shamelessly taken from the clock
+ * framework:
+ *
+ * We do slightly fuzzy matching here:
+ * An entry with a NULL ID is assumed to be a wildcard.
+ * If an entry has a device ID, it must match
+ * If an entry has a connection ID, it must match
+ * Then we take the most specific entry - with the following order
+ * of precedence: dev+con > dev only > con only.
+ */
+ mutex_lock(&pwm_lookup_lock);
+
+ list_for_each_entry(p, &pwm_lookup_list, list) {
+ match = 0;
+
+ if (p->dev_id) {
+ if (!dev_id || strcmp(p->dev_id, dev_id))
+ continue;
+
+ match += 2;
+ }
+
+ if (p->con_id) {
+ if (!con_id || strcmp(p->con_id, con_id))
+ continue;
+
+ match += 1;
+ }
+
+ if (match > best) {
+ chosen = p;
+
+ if (match != 3)
+ best = match;
+ else
+ break;
+ }
+ }
+
+ mutex_unlock(&pwm_lookup_lock);
+
+ if (!chosen)
+ return ERR_PTR(-ENODEV);
+
+ chip = pwmchip_find_by_name(chosen->provider);
+
+ /*
+ * If the lookup entry specifies a module, load the module and retry
+ * the PWM chip lookup. This can be used to work around driver load
+ * ordering issues if driver's can't be made to properly support the
+ * deferred probe mechanism.
+ */
+ if (!chip && chosen->module) {
+ err = request_module(chosen->module);
+ if (err == 0)
+ chip = pwmchip_find_by_name(chosen->provider);
+ }
+
+ if (!chip)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ dl = pwm_device_link_add(dev, pwm);
+ if (IS_ERR(dl)) {
+ pwm_free(pwm);
+ return ERR_CAST(dl);
+ }
+
+ pwm->args.period = chosen->period;
+ pwm->args.polarity = chosen->polarity;
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(pwm_get);
+
+/**
+ * pwm_put() - release a PWM device
+ * @pwm: PWM device
+ */
+void pwm_put(struct pwm_device *pwm)
+{
+ if (!pwm)
+ return;
+
+ mutex_lock(&pwm_lock);
+
+ if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) {
+ pr_warn("PWM device already freed\n");
+ goto out;
+ }
+
+ if (pwm->chip->ops->free)
+ pwm->chip->ops->free(pwm->chip, pwm);
+
+ pwm_set_chip_data(pwm, NULL);
+ pwm->label = NULL;
+
+ module_put(pwm->chip->ops->owner);
+out:
+ mutex_unlock(&pwm_lock);
+}
+EXPORT_SYMBOL_GPL(pwm_put);
+
+static void devm_pwm_release(void *pwm)
+{
+ pwm_put(pwm);
+}
+
+/**
+ * devm_pwm_get() - resource managed pwm_get()
+ * @dev: device for PWM consumer
+ * @con_id: consumer name
+ *
+ * This function performs like pwm_get() but the acquired PWM device will
+ * automatically be released on driver detach.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id)
+{
+ struct pwm_device *pwm;
+ int ret;
+
+ pwm = pwm_get(dev, con_id);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ ret = devm_add_action_or_reset(dev, devm_pwm_release, pwm);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_pwm_get);
+
+/**
+ * devm_fwnode_pwm_get() - request a resource managed PWM from firmware node
+ * @dev: device for PWM consumer
+ * @fwnode: firmware node to get the PWM from
+ * @con_id: consumer name
+ *
+ * Returns the PWM device parsed from the firmware node. See of_pwm_get() and
+ * acpi_pwm_get() for a detailed description.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+struct pwm_device *devm_fwnode_pwm_get(struct device *dev,
+ struct fwnode_handle *fwnode,
+ const char *con_id)
+{
+ struct pwm_device *pwm = ERR_PTR(-ENODEV);
+ int ret;
+
+ if (is_of_node(fwnode))
+ pwm = of_pwm_get(dev, to_of_node(fwnode), con_id);
+ else if (is_acpi_node(fwnode))
+ pwm = acpi_pwm_get(fwnode);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ ret = devm_add_action_or_reset(dev, devm_pwm_release, pwm);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_fwnode_pwm_get);
+
+#ifdef CONFIG_DEBUG_FS
+static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
+{
+ unsigned int i;
+
+ for (i = 0; i < chip->npwm; i++) {
+ struct pwm_device *pwm = &chip->pwms[i];
+ struct pwm_state state;
+
+ pwm_get_state(pwm, &state);
+
+ seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label);
+
+ if (test_bit(PWMF_REQUESTED, &pwm->flags))
+ seq_puts(s, " requested");
+
+ if (state.enabled)
+ seq_puts(s, " enabled");
+
+ seq_printf(s, " period: %llu ns", state.period);
+ seq_printf(s, " duty: %llu ns", state.duty_cycle);
+ seq_printf(s, " polarity: %s",
+ state.polarity ? "inverse" : "normal");
+
+ if (state.usage_power)
+ seq_puts(s, " usage_power");
+
+ seq_puts(s, "\n");
+ }
+}
+
+static void *pwm_seq_start(struct seq_file *s, loff_t *pos)
+{
+ mutex_lock(&pwm_lock);
+ s->private = "";
+
+ return seq_list_start(&pwm_chips, *pos);
+}
+
+static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+ s->private = "\n";
+
+ return seq_list_next(v, &pwm_chips, pos);
+}
+
+static void pwm_seq_stop(struct seq_file *s, void *v)
+{
+ mutex_unlock(&pwm_lock);
+}
+
+static int pwm_seq_show(struct seq_file *s, void *v)
+{
+ struct pwm_chip *chip = list_entry(v, struct pwm_chip, list);
+
+ seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private,
+ chip->dev->bus ? chip->dev->bus->name : "no-bus",
+ dev_name(chip->dev), chip->npwm,
+ (chip->npwm != 1) ? "s" : "");
+
+ pwm_dbg_show(chip, s);
+
+ return 0;
+}
+
+static const struct seq_operations pwm_debugfs_sops = {
+ .start = pwm_seq_start,
+ .next = pwm_seq_next,
+ .stop = pwm_seq_stop,
+ .show = pwm_seq_show,
+};
+
+DEFINE_SEQ_ATTRIBUTE(pwm_debugfs);
+
+static int __init pwm_debugfs_init(void)
+{
+ debugfs_create_file("pwm", 0444, NULL, NULL, &pwm_debugfs_fops);
+
+ return 0;
+}
+subsys_initcall(pwm_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */