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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/platform/chrome/wilco_ec/telemetry.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/platform/chrome/wilco_ec/telemetry.c')
-rw-r--r-- | drivers/platform/chrome/wilco_ec/telemetry.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/drivers/platform/chrome/wilco_ec/telemetry.c b/drivers/platform/chrome/wilco_ec/telemetry.c new file mode 100644 index 000000000..60da7a29f --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/telemetry.c @@ -0,0 +1,472 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Telemetry communication for Wilco EC + * + * Copyright 2019 Google LLC + * + * The Wilco Embedded Controller is able to send telemetry data + * which is useful for enterprise applications. A daemon running on + * the OS sends a command to the EC via a write() to a char device, + * and can read the response with a read(). The write() request is + * verified by the driver to ensure that it is performing only one + * of the allowlisted commands, and that no extraneous data is + * being transmitted to the EC. The response is passed directly + * back to the reader with no modification. + * + * The character device will appear as /dev/wilco_telemN, where N + * is some small non-negative integer, starting with 0. Only one + * process may have the file descriptor open at a time. The calling + * userspace program needs to keep the device file descriptor open + * between the calls to write() and read() in order to preserve the + * response. Up to 32 bytes will be available for reading. + * + * For testing purposes, try requesting the EC's firmware build + * date, by sending the WILCO_EC_TELEM_GET_VERSION command with + * argument index=3. i.e. write [0x38, 0x00, 0x03] + * to the device node. An ASCII string of the build date is + * returned. + */ + +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/uaccess.h> + +#define TELEM_DEV_NAME "wilco_telem" +#define TELEM_CLASS_NAME TELEM_DEV_NAME +#define DRV_NAME TELEM_DEV_NAME +#define TELEM_DEV_NAME_FMT (TELEM_DEV_NAME "%d") +static struct class telem_class = { + .owner = THIS_MODULE, + .name = TELEM_CLASS_NAME, +}; + +/* Keep track of all the device numbers used. */ +#define TELEM_MAX_DEV 128 +static int telem_major; +static DEFINE_IDA(telem_ida); + +/* EC telemetry command codes */ +#define WILCO_EC_TELEM_GET_LOG 0x99 +#define WILCO_EC_TELEM_GET_VERSION 0x38 +#define WILCO_EC_TELEM_GET_FAN_INFO 0x2E +#define WILCO_EC_TELEM_GET_DIAG_INFO 0xFA +#define WILCO_EC_TELEM_GET_TEMP_INFO 0x95 +#define WILCO_EC_TELEM_GET_TEMP_READ 0x2C +#define WILCO_EC_TELEM_GET_BATT_EXT_INFO 0x07 +#define WILCO_EC_TELEM_GET_BATT_PPID_INFO 0x8A + +#define TELEM_ARGS_SIZE_MAX 30 + +/* + * The following telem_args_get_* structs are embedded within the |args| field + * of wilco_ec_telem_request. + */ + +struct telem_args_get_log { + u8 log_type; + u8 log_index; +} __packed; + +/* + * Get a piece of info about the EC firmware version: + * 0 = label + * 1 = svn_rev + * 2 = model_no + * 3 = build_date + * 4 = frio_version + */ +struct telem_args_get_version { + u8 index; +} __packed; + +struct telem_args_get_fan_info { + u8 command; + u8 fan_number; + u8 arg; +} __packed; + +struct telem_args_get_diag_info { + u8 type; + u8 sub_type; +} __packed; + +struct telem_args_get_temp_info { + u8 command; + u8 index; + u8 field; + u8 zone; +} __packed; + +struct telem_args_get_temp_read { + u8 sensor_index; +} __packed; + +struct telem_args_get_batt_ext_info { + u8 var_args[5]; +} __packed; + +struct telem_args_get_batt_ppid_info { + u8 always1; /* Should always be 1 */ +} __packed; + +/** + * struct wilco_ec_telem_request - Telemetry command and arguments sent to EC. + * @command: One of WILCO_EC_TELEM_GET_* command codes. + * @reserved: Must be 0. + * @args: The first N bytes are one of telem_args_get_* structs, the rest is 0. + */ +struct wilco_ec_telem_request { + u8 command; + u8 reserved; + union { + u8 buf[TELEM_ARGS_SIZE_MAX]; + struct telem_args_get_log get_log; + struct telem_args_get_version get_version; + struct telem_args_get_fan_info get_fan_info; + struct telem_args_get_diag_info get_diag_info; + struct telem_args_get_temp_info get_temp_info; + struct telem_args_get_temp_read get_temp_read; + struct telem_args_get_batt_ext_info get_batt_ext_info; + struct telem_args_get_batt_ppid_info get_batt_ppid_info; + } args; +} __packed; + +/** + * check_telem_request() - Ensure that a request from userspace is valid. + * @rq: Request buffer copied from userspace. + * @size: Number of bytes copied from userspace. + * + * Return: 0 if valid, -EINVAL if bad command or reserved byte is non-zero, + * -EMSGSIZE if the request is too long. + * + * We do not want to allow userspace to send arbitrary telemetry commands to + * the EC. Therefore we check to ensure that + * 1. The request follows the format of struct wilco_ec_telem_request. + * 2. The supplied command code is one of the allowlisted commands. + * 3. The request only contains the necessary data for the header and arguments. + */ +static int check_telem_request(struct wilco_ec_telem_request *rq, + size_t size) +{ + size_t max_size = offsetof(struct wilco_ec_telem_request, args); + + if (rq->reserved) + return -EINVAL; + + switch (rq->command) { + case WILCO_EC_TELEM_GET_LOG: + max_size += sizeof(rq->args.get_log); + break; + case WILCO_EC_TELEM_GET_VERSION: + max_size += sizeof(rq->args.get_version); + break; + case WILCO_EC_TELEM_GET_FAN_INFO: + max_size += sizeof(rq->args.get_fan_info); + break; + case WILCO_EC_TELEM_GET_DIAG_INFO: + max_size += sizeof(rq->args.get_diag_info); + break; + case WILCO_EC_TELEM_GET_TEMP_INFO: + max_size += sizeof(rq->args.get_temp_info); + break; + case WILCO_EC_TELEM_GET_TEMP_READ: + max_size += sizeof(rq->args.get_temp_read); + break; + case WILCO_EC_TELEM_GET_BATT_EXT_INFO: + max_size += sizeof(rq->args.get_batt_ext_info); + break; + case WILCO_EC_TELEM_GET_BATT_PPID_INFO: + if (rq->args.get_batt_ppid_info.always1 != 1) + return -EINVAL; + + max_size += sizeof(rq->args.get_batt_ppid_info); + break; + default: + return -EINVAL; + } + + return (size <= max_size) ? 0 : -EMSGSIZE; +} + +/** + * struct telem_device_data - Data for a Wilco EC device that queries telemetry. + * @cdev: Char dev that userspace reads and polls from. + * @dev: Device associated with the %cdev. + * @ec: Wilco EC that we will be communicating with using the mailbox interface. + * @available: Boolean of if the device can be opened. + */ +struct telem_device_data { + struct device dev; + struct cdev cdev; + struct wilco_ec_device *ec; + atomic_t available; +}; + +#define TELEM_RESPONSE_SIZE EC_MAILBOX_DATA_SIZE + +/** + * struct telem_session_data - Data that exists between open() and release(). + * @dev_data: Pointer to get back to the device data and EC. + * @request: Command and arguments sent to EC. + * @response: Response buffer of data from EC. + * @has_msg: Is there data available to read from a previous write? + */ +struct telem_session_data { + struct telem_device_data *dev_data; + struct wilco_ec_telem_request request; + u8 response[TELEM_RESPONSE_SIZE]; + bool has_msg; +}; + +/** + * telem_open() - Callback for when the device node is opened. + * @inode: inode for this char device node. + * @filp: file for this char device node. + * + * We need to ensure that after writing a command to the device, + * the same userspace process reads the corresponding result. + * Therefore, we increment a refcount on opening the device, so that + * only one process can communicate with the EC at a time. + * + * Return: 0 on success, or negative error code on failure. + */ +static int telem_open(struct inode *inode, struct file *filp) +{ + struct telem_device_data *dev_data; + struct telem_session_data *sess_data; + + /* Ensure device isn't already open */ + dev_data = container_of(inode->i_cdev, struct telem_device_data, cdev); + if (atomic_cmpxchg(&dev_data->available, 1, 0) == 0) + return -EBUSY; + + get_device(&dev_data->dev); + + sess_data = kzalloc(sizeof(*sess_data), GFP_KERNEL); + if (!sess_data) { + atomic_set(&dev_data->available, 1); + return -ENOMEM; + } + sess_data->dev_data = dev_data; + sess_data->has_msg = false; + + stream_open(inode, filp); + filp->private_data = sess_data; + + return 0; +} + +static ssize_t telem_write(struct file *filp, const char __user *buf, + size_t count, loff_t *pos) +{ + struct telem_session_data *sess_data = filp->private_data; + struct wilco_ec_message msg = {}; + int ret; + + if (count > sizeof(sess_data->request)) + return -EMSGSIZE; + memset(&sess_data->request, 0, sizeof(sess_data->request)); + if (copy_from_user(&sess_data->request, buf, count)) + return -EFAULT; + ret = check_telem_request(&sess_data->request, count); + if (ret < 0) + return ret; + + memset(sess_data->response, 0, sizeof(sess_data->response)); + msg.type = WILCO_EC_MSG_TELEMETRY; + msg.request_data = &sess_data->request; + msg.request_size = sizeof(sess_data->request); + msg.response_data = sess_data->response; + msg.response_size = sizeof(sess_data->response); + + ret = wilco_ec_mailbox(sess_data->dev_data->ec, &msg); + if (ret < 0) + return ret; + if (ret != sizeof(sess_data->response)) + return -EMSGSIZE; + + sess_data->has_msg = true; + + return count; +} + +static ssize_t telem_read(struct file *filp, char __user *buf, size_t count, + loff_t *pos) +{ + struct telem_session_data *sess_data = filp->private_data; + + if (!sess_data->has_msg) + return -ENODATA; + if (count > sizeof(sess_data->response)) + return -EINVAL; + + if (copy_to_user(buf, sess_data->response, count)) + return -EFAULT; + + sess_data->has_msg = false; + + return count; +} + +static int telem_release(struct inode *inode, struct file *filp) +{ + struct telem_session_data *sess_data = filp->private_data; + + atomic_set(&sess_data->dev_data->available, 1); + put_device(&sess_data->dev_data->dev); + kfree(sess_data); + + return 0; +} + +static const struct file_operations telem_fops = { + .open = telem_open, + .write = telem_write, + .read = telem_read, + .release = telem_release, + .llseek = no_llseek, + .owner = THIS_MODULE, +}; + +/** + * telem_device_free() - Callback to free the telem_device_data structure. + * @d: The device embedded in our device data, which we have been ref counting. + * + * Once all open file descriptors are closed and the device has been removed, + * the refcount of the device will fall to 0 and this will be called. + */ +static void telem_device_free(struct device *d) +{ + struct telem_device_data *dev_data; + + dev_data = container_of(d, struct telem_device_data, dev); + kfree(dev_data); +} + +/** + * telem_device_probe() - Callback when creating a new device. + * @pdev: platform device that we will be receiving telems from. + * + * This finds a free minor number for the device, allocates and initializes + * some device data, and creates a new device and char dev node. + * + * Return: 0 on success, negative error code on failure. + */ +static int telem_device_probe(struct platform_device *pdev) +{ + struct telem_device_data *dev_data; + int error, minor; + + /* Get the next available device number */ + minor = ida_alloc_max(&telem_ida, TELEM_MAX_DEV-1, GFP_KERNEL); + if (minor < 0) { + error = minor; + dev_err(&pdev->dev, "Failed to find minor number: %d\n", error); + return error; + } + + dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL); + if (!dev_data) { + ida_simple_remove(&telem_ida, minor); + return -ENOMEM; + } + + /* Initialize the device data */ + dev_data->ec = dev_get_platdata(&pdev->dev); + atomic_set(&dev_data->available, 1); + platform_set_drvdata(pdev, dev_data); + + /* Initialize the device */ + dev_data->dev.devt = MKDEV(telem_major, minor); + dev_data->dev.class = &telem_class; + dev_data->dev.release = telem_device_free; + dev_set_name(&dev_data->dev, TELEM_DEV_NAME_FMT, minor); + device_initialize(&dev_data->dev); + + /* Initialize the character device and add it to userspace */; + cdev_init(&dev_data->cdev, &telem_fops); + error = cdev_device_add(&dev_data->cdev, &dev_data->dev); + if (error) { + put_device(&dev_data->dev); + ida_simple_remove(&telem_ida, minor); + return error; + } + + return 0; +} + +static int telem_device_remove(struct platform_device *pdev) +{ + struct telem_device_data *dev_data = platform_get_drvdata(pdev); + + cdev_device_del(&dev_data->cdev, &dev_data->dev); + ida_simple_remove(&telem_ida, MINOR(dev_data->dev.devt)); + put_device(&dev_data->dev); + + return 0; +} + +static struct platform_driver telem_driver = { + .probe = telem_device_probe, + .remove = telem_device_remove, + .driver = { + .name = DRV_NAME, + }, +}; + +static int __init telem_module_init(void) +{ + dev_t dev_num = 0; + int ret; + + ret = class_register(&telem_class); + if (ret) { + pr_err(DRV_NAME ": Failed registering class: %d\n", ret); + return ret; + } + + /* Request the kernel for device numbers, starting with minor=0 */ + ret = alloc_chrdev_region(&dev_num, 0, TELEM_MAX_DEV, TELEM_DEV_NAME); + if (ret) { + pr_err(DRV_NAME ": Failed allocating dev numbers: %d\n", ret); + goto destroy_class; + } + telem_major = MAJOR(dev_num); + + ret = platform_driver_register(&telem_driver); + if (ret < 0) { + pr_err(DRV_NAME ": Failed registering driver: %d\n", ret); + goto unregister_region; + } + + return 0; + +unregister_region: + unregister_chrdev_region(MKDEV(telem_major, 0), TELEM_MAX_DEV); +destroy_class: + class_unregister(&telem_class); + ida_destroy(&telem_ida); + return ret; +} + +static void __exit telem_module_exit(void) +{ + platform_driver_unregister(&telem_driver); + unregister_chrdev_region(MKDEV(telem_major, 0), TELEM_MAX_DEV); + class_unregister(&telem_class); + ida_destroy(&telem_ida); +} + +module_init(telem_module_init); +module_exit(telem_module_exit); + +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_DESCRIPTION("Wilco EC telemetry driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); |