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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/devfreq/devfreq-event.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/devfreq/devfreq-event.c')
-rw-r--r--drivers/devfreq/devfreq-event.c482
1 files changed, 482 insertions, 0 deletions
diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c
new file mode 100644
index 000000000..f041edccd
--- /dev/null
+++ b/drivers/devfreq/devfreq-event.c
@@ -0,0 +1,482 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * devfreq-event: a framework to provide raw data and events of devfreq devices
+ *
+ * Copyright (C) 2015 Samsung Electronics
+ * Author: Chanwoo Choi <cw00.choi@samsung.com>
+ *
+ * This driver is based on drivers/devfreq/devfreq.c.
+ */
+
+#include <linux/devfreq-event.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/of.h>
+
+static struct class *devfreq_event_class;
+
+/* The list of all devfreq event list */
+static LIST_HEAD(devfreq_event_list);
+static DEFINE_MUTEX(devfreq_event_list_lock);
+
+#define to_devfreq_event(DEV) container_of(DEV, struct devfreq_event_dev, dev)
+
+/**
+ * devfreq_event_enable_edev() - Enable the devfreq-event dev and increase
+ * the enable_count of devfreq-event dev.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function increase the enable_count and enable the
+ * devfreq-event device. The devfreq-event device should be enabled before
+ * using it by devfreq device.
+ */
+int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
+{
+ int ret = 0;
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ mutex_lock(&edev->lock);
+ if (edev->desc->ops && edev->desc->ops->enable
+ && edev->enable_count == 0) {
+ ret = edev->desc->ops->enable(edev);
+ if (ret < 0)
+ goto err;
+ }
+ edev->enable_count++;
+err:
+ mutex_unlock(&edev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_enable_edev);
+
+/**
+ * devfreq_event_disable_edev() - Disable the devfreq-event dev and decrease
+ * the enable_count of the devfreq-event dev.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function decrease the enable_count and disable the
+ * devfreq-event device. After the devfreq-event device is disabled,
+ * devfreq device can't use the devfreq-event device for get/set/reset
+ * operations.
+ */
+int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
+{
+ int ret = 0;
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ mutex_lock(&edev->lock);
+ if (edev->enable_count <= 0) {
+ dev_warn(&edev->dev, "unbalanced enable_count\n");
+ ret = -EIO;
+ goto err;
+ }
+
+ if (edev->desc->ops && edev->desc->ops->disable
+ && edev->enable_count == 1) {
+ ret = edev->desc->ops->disable(edev);
+ if (ret < 0)
+ goto err;
+ }
+ edev->enable_count--;
+err:
+ mutex_unlock(&edev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_disable_edev);
+
+/**
+ * devfreq_event_is_enabled() - Check whether devfreq-event dev is enabled or
+ * not.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function check whether devfreq-event dev is enabled or not.
+ * If return true, the devfreq-event dev is enabeld. If return false, the
+ * devfreq-event dev is disabled.
+ */
+bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
+{
+ bool enabled = false;
+
+ if (!edev || !edev->desc)
+ return enabled;
+
+ mutex_lock(&edev->lock);
+
+ if (edev->enable_count > 0)
+ enabled = true;
+
+ mutex_unlock(&edev->lock);
+
+ return enabled;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_is_enabled);
+
+/**
+ * devfreq_event_set_event() - Set event to devfreq-event dev to start.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function set the event to the devfreq-event device to start
+ * for getting the event data which could be various event type.
+ */
+int devfreq_event_set_event(struct devfreq_event_dev *edev)
+{
+ int ret;
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ if (!edev->desc->ops || !edev->desc->ops->set_event)
+ return -EINVAL;
+
+ if (!devfreq_event_is_enabled(edev))
+ return -EPERM;
+
+ mutex_lock(&edev->lock);
+ ret = edev->desc->ops->set_event(edev);
+ mutex_unlock(&edev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_set_event);
+
+/**
+ * devfreq_event_get_event() - Get {load|total}_count from devfreq-event dev.
+ * @edev : the devfreq-event device
+ * @edata : the calculated data of devfreq-event device
+ *
+ * Note that this function get the calculated event data from devfreq-event dev
+ * after stoping the progress of whole sequence of devfreq-event dev.
+ */
+int devfreq_event_get_event(struct devfreq_event_dev *edev,
+ struct devfreq_event_data *edata)
+{
+ int ret;
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ if (!edev->desc->ops || !edev->desc->ops->get_event)
+ return -EINVAL;
+
+ if (!devfreq_event_is_enabled(edev))
+ return -EINVAL;
+
+ edata->total_count = edata->load_count = 0;
+
+ mutex_lock(&edev->lock);
+ ret = edev->desc->ops->get_event(edev, edata);
+ if (ret < 0)
+ edata->total_count = edata->load_count = 0;
+ mutex_unlock(&edev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_event);
+
+/**
+ * devfreq_event_reset_event() - Reset all opeations of devfreq-event dev.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function stop all operations of devfreq-event dev and reset
+ * the current event data to make the devfreq-event device into initial state.
+ */
+int devfreq_event_reset_event(struct devfreq_event_dev *edev)
+{
+ int ret = 0;
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ if (!devfreq_event_is_enabled(edev))
+ return -EPERM;
+
+ mutex_lock(&edev->lock);
+ if (edev->desc->ops && edev->desc->ops->reset)
+ ret = edev->desc->ops->reset(edev);
+ mutex_unlock(&edev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_reset_event);
+
+/**
+ * devfreq_event_get_edev_by_phandle() - Get the devfreq-event dev from
+ * devicetree.
+ * @dev : the pointer to the given device
+ * @phandle_name: name of property holding a phandle value
+ * @index : the index into list of devfreq-event device
+ *
+ * Note that this function return the pointer of devfreq-event device.
+ */
+struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(struct device *dev,
+ const char *phandle_name, int index)
+{
+ struct device_node *node;
+ struct devfreq_event_dev *edev;
+
+ if (!dev->of_node || !phandle_name)
+ return ERR_PTR(-EINVAL);
+
+ node = of_parse_phandle(dev->of_node, phandle_name, index);
+ if (!node)
+ return ERR_PTR(-ENODEV);
+
+ mutex_lock(&devfreq_event_list_lock);
+ list_for_each_entry(edev, &devfreq_event_list, node) {
+ if (edev->dev.parent && device_match_of_node(edev->dev.parent, node))
+ goto out;
+ }
+
+ list_for_each_entry(edev, &devfreq_event_list, node) {
+ if (of_node_name_eq(node, edev->desc->name))
+ goto out;
+ }
+ edev = NULL;
+out:
+ mutex_unlock(&devfreq_event_list_lock);
+
+ if (!edev) {
+ of_node_put(node);
+ return ERR_PTR(-ENODEV);
+ }
+
+ of_node_put(node);
+
+ return edev;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_edev_by_phandle);
+
+/**
+ * devfreq_event_get_edev_count() - Get the count of devfreq-event dev
+ * @dev : the pointer to the given device
+ * @phandle_name: name of property holding a phandle value
+ *
+ * Note that this function return the count of devfreq-event devices.
+ */
+int devfreq_event_get_edev_count(struct device *dev, const char *phandle_name)
+{
+ int count;
+
+ if (!dev->of_node || !phandle_name) {
+ dev_err(dev, "device does not have a device node entry\n");
+ return -EINVAL;
+ }
+
+ count = of_property_count_elems_of_size(dev->of_node, phandle_name,
+ sizeof(u32));
+ if (count < 0) {
+ dev_err(dev,
+ "failed to get the count of devfreq-event in %pOF node\n",
+ dev->of_node);
+ return count;
+ }
+
+ return count;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_edev_count);
+
+static void devfreq_event_release_edev(struct device *dev)
+{
+ struct devfreq_event_dev *edev = to_devfreq_event(dev);
+
+ kfree(edev);
+}
+
+/**
+ * devfreq_event_add_edev() - Add new devfreq-event device.
+ * @dev : the device owning the devfreq-event device being created
+ * @desc : the devfreq-event device's descriptor which include essential
+ * data for devfreq-event device.
+ *
+ * Note that this function add new devfreq-event device to devfreq-event class
+ * list and register the device of the devfreq-event device.
+ */
+struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
+ struct devfreq_event_desc *desc)
+{
+ struct devfreq_event_dev *edev;
+ static atomic_t event_no = ATOMIC_INIT(-1);
+ int ret;
+
+ if (!dev || !desc)
+ return ERR_PTR(-EINVAL);
+
+ if (!desc->name || !desc->ops)
+ return ERR_PTR(-EINVAL);
+
+ if (!desc->ops->set_event || !desc->ops->get_event)
+ return ERR_PTR(-EINVAL);
+
+ edev = kzalloc(sizeof(struct devfreq_event_dev), GFP_KERNEL);
+ if (!edev)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&edev->lock);
+ edev->desc = desc;
+ edev->enable_count = 0;
+ edev->dev.parent = dev;
+ edev->dev.class = devfreq_event_class;
+ edev->dev.release = devfreq_event_release_edev;
+
+ dev_set_name(&edev->dev, "event%d", atomic_inc_return(&event_no));
+ ret = device_register(&edev->dev);
+ if (ret < 0) {
+ put_device(&edev->dev);
+ return ERR_PTR(ret);
+ }
+ dev_set_drvdata(&edev->dev, edev);
+
+ INIT_LIST_HEAD(&edev->node);
+
+ mutex_lock(&devfreq_event_list_lock);
+ list_add(&edev->node, &devfreq_event_list);
+ mutex_unlock(&devfreq_event_list_lock);
+
+ return edev;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_add_edev);
+
+/**
+ * devfreq_event_remove_edev() - Remove the devfreq-event device registered.
+ * @edev : the devfreq-event device
+ *
+ * Note that this function removes the registered devfreq-event device.
+ */
+int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
+{
+ if (!edev)
+ return -EINVAL;
+
+ WARN_ON(edev->enable_count);
+
+ mutex_lock(&devfreq_event_list_lock);
+ list_del(&edev->node);
+ mutex_unlock(&devfreq_event_list_lock);
+
+ device_unregister(&edev->dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_remove_edev);
+
+static int devm_devfreq_event_match(struct device *dev, void *res, void *data)
+{
+ struct devfreq_event_dev **r = res;
+
+ if (WARN_ON(!r || !*r))
+ return 0;
+
+ return *r == data;
+}
+
+static void devm_devfreq_event_release(struct device *dev, void *res)
+{
+ devfreq_event_remove_edev(*(struct devfreq_event_dev **)res);
+}
+
+/**
+ * devm_devfreq_event_add_edev() - Resource-managed devfreq_event_add_edev()
+ * @dev : the device owning the devfreq-event device being created
+ * @desc : the devfreq-event device's descriptor which include essential
+ * data for devfreq-event device.
+ *
+ * Note that this function manages automatically the memory of devfreq-event
+ * device using device resource management and simplify the free operation
+ * for memory of devfreq-event device.
+ */
+struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
+ struct devfreq_event_desc *desc)
+{
+ struct devfreq_event_dev **ptr, *edev;
+
+ ptr = devres_alloc(devm_devfreq_event_release, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ edev = devfreq_event_add_edev(dev, desc);
+ if (IS_ERR(edev)) {
+ devres_free(ptr);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ *ptr = edev;
+ devres_add(dev, ptr);
+
+ return edev;
+}
+EXPORT_SYMBOL_GPL(devm_devfreq_event_add_edev);
+
+/**
+ * devm_devfreq_event_remove_edev()- Resource-managed devfreq_event_remove_edev()
+ * @dev : the device owning the devfreq-event device being created
+ * @edev : the devfreq-event device
+ *
+ * Note that this function manages automatically the memory of devfreq-event
+ * device using device resource management.
+ */
+void devm_devfreq_event_remove_edev(struct device *dev,
+ struct devfreq_event_dev *edev)
+{
+ WARN_ON(devres_release(dev, devm_devfreq_event_release,
+ devm_devfreq_event_match, edev));
+}
+EXPORT_SYMBOL_GPL(devm_devfreq_event_remove_edev);
+
+/*
+ * Device attributes for devfreq-event class.
+ */
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct devfreq_event_dev *edev = to_devfreq_event(dev);
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ return sprintf(buf, "%s\n", edev->desc->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t enable_count_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct devfreq_event_dev *edev = to_devfreq_event(dev);
+
+ if (!edev || !edev->desc)
+ return -EINVAL;
+
+ return sprintf(buf, "%d\n", edev->enable_count);
+}
+static DEVICE_ATTR_RO(enable_count);
+
+static struct attribute *devfreq_event_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_enable_count.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(devfreq_event);
+
+static int __init devfreq_event_init(void)
+{
+ devfreq_event_class = class_create(THIS_MODULE, "devfreq-event");
+ if (IS_ERR(devfreq_event_class)) {
+ pr_err("%s: couldn't create class\n", __FILE__);
+ return PTR_ERR(devfreq_event_class);
+ }
+
+ devfreq_event_class->dev_groups = devfreq_event_groups;
+
+ return 0;
+}
+subsys_initcall(devfreq_event_init);