aboutsummaryrefslogtreecommitdiff
path: root/drivers/platform/chrome/cros_ec_lightbar.c
diff options
context:
space:
mode:
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/platform/chrome/cros_ec_lightbar.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/platform/chrome/cros_ec_lightbar.c')
-rw-r--r--drivers/platform/chrome/cros_ec_lightbar.c613
1 files changed, 613 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c
new file mode 100644
index 000000000..376425bbd
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lightbar.c
@@ -0,0 +1,613 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Expose the Chromebook Pixel lightbar to userspace
+//
+// Copyright (C) 2014 Google, Inc.
+
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kobject.h>
+#include <linux/kstrtox.h>
+#include <linux/module.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+
+#define DRV_NAME "cros-ec-lightbar"
+
+/* Rate-limit the lightbar interface to prevent DoS. */
+static unsigned long lb_interval_jiffies = 50 * HZ / 1000;
+
+/*
+ * Whether or not we have given userspace control of the lightbar.
+ * If this is true, we won't do anything during suspend/resume.
+ */
+static bool userspace_control;
+
+static ssize_t interval_msec_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned long msec = lb_interval_jiffies * 1000 / HZ;
+
+ return sysfs_emit(buf, "%lu\n", msec);
+}
+
+static ssize_t interval_msec_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long msec;
+
+ if (kstrtoul(buf, 0, &msec))
+ return -EINVAL;
+
+ lb_interval_jiffies = msec * HZ / 1000;
+
+ return count;
+}
+
+static DEFINE_MUTEX(lb_mutex);
+/* Return 0 if able to throttle correctly, error otherwise */
+static int lb_throttle(void)
+{
+ static unsigned long last_access;
+ unsigned long now, next_timeslot;
+ long delay;
+ int ret = 0;
+
+ mutex_lock(&lb_mutex);
+
+ now = jiffies;
+ next_timeslot = last_access + lb_interval_jiffies;
+
+ if (time_before(now, next_timeslot)) {
+ delay = (long)(next_timeslot) - (long)now;
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (schedule_timeout(delay) > 0) {
+ /* interrupted - just abort */
+ ret = -EINTR;
+ goto out;
+ }
+ now = jiffies;
+ }
+
+ last_access = now;
+out:
+ mutex_unlock(&lb_mutex);
+
+ return ret;
+}
+
+static struct cros_ec_command *alloc_lightbar_cmd_msg(struct cros_ec_dev *ec)
+{
+ struct cros_ec_command *msg;
+ int len;
+
+ len = max(sizeof(struct ec_params_lightbar),
+ sizeof(struct ec_response_lightbar));
+
+ msg = kmalloc(sizeof(*msg) + len, GFP_KERNEL);
+ if (!msg)
+ return NULL;
+
+ msg->version = 0;
+ msg->command = EC_CMD_LIGHTBAR_CMD + ec->cmd_offset;
+ msg->outsize = sizeof(struct ec_params_lightbar);
+ msg->insize = sizeof(struct ec_response_lightbar);
+
+ return msg;
+}
+
+static int get_lightbar_version(struct cros_ec_dev *ec,
+ uint32_t *ver_ptr, uint32_t *flg_ptr)
+{
+ struct ec_params_lightbar *param;
+ struct ec_response_lightbar *resp;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return 0;
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_VERSION;
+ msg->outsize = sizeof(param->cmd);
+ msg->result = sizeof(resp->version);
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0 && ret != -EINVAL) {
+ ret = 0;
+ goto exit;
+ }
+
+ switch (msg->result) {
+ case EC_RES_INVALID_PARAM:
+ /* Pixel had no version command. */
+ if (ver_ptr)
+ *ver_ptr = 0;
+ if (flg_ptr)
+ *flg_ptr = 0;
+ ret = 1;
+ goto exit;
+
+ case EC_RES_SUCCESS:
+ resp = (struct ec_response_lightbar *)msg->data;
+
+ /* Future devices w/lightbars should implement this command */
+ if (ver_ptr)
+ *ver_ptr = resp->version.num;
+ if (flg_ptr)
+ *flg_ptr = resp->version.flags;
+ ret = 1;
+ goto exit;
+ }
+
+ /* Anything else (ie, EC_RES_INVALID_COMMAND) - no lightbar */
+ ret = 0;
+exit:
+ kfree(msg);
+ return ret;
+}
+
+static ssize_t version_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ uint32_t version = 0, flags = 0;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+ int ret;
+
+ ret = lb_throttle();
+ if (ret)
+ return ret;
+
+ /* This should always succeed, because we check during init. */
+ if (!get_lightbar_version(ec, &version, &flags))
+ return -EIO;
+
+ return sysfs_emit(buf, "%d %d\n", version, flags);
+}
+
+static ssize_t brightness_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ int ret;
+ unsigned int val;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+
+ if (kstrtouint(buf, 0, &val))
+ return -EINVAL;
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_SET_BRIGHTNESS;
+ param->set_brightness.num = val;
+ ret = lb_throttle();
+ if (ret)
+ goto exit;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto exit;
+
+ ret = count;
+exit:
+ kfree(msg);
+ return ret;
+}
+
+
+/*
+ * We expect numbers, and we'll keep reading until we find them, skipping over
+ * any whitespace (sysfs guarantees that the input is null-terminated). Every
+ * four numbers are sent to the lightbar as <LED,R,G,B>. We fail at the first
+ * parsing error, if we don't parse any numbers, or if we have numbers left
+ * over.
+ */
+static ssize_t led_rgb_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+ unsigned int val[4];
+ int ret, i = 0, j = 0, ok = 0;
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ do {
+ /* Skip any whitespace */
+ while (*buf && isspace(*buf))
+ buf++;
+
+ if (!*buf)
+ break;
+
+ ret = sscanf(buf, "%i", &val[i++]);
+ if (ret == 0)
+ goto exit;
+
+ if (i == 4) {
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_SET_RGB;
+ param->set_rgb.led = val[0];
+ param->set_rgb.red = val[1];
+ param->set_rgb.green = val[2];
+ param->set_rgb.blue = val[3];
+ /*
+ * Throttle only the first of every four transactions,
+ * so that the user can update all four LEDs at once.
+ */
+ if ((j++ % 4) == 0) {
+ ret = lb_throttle();
+ if (ret)
+ goto exit;
+ }
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto exit;
+
+ i = 0;
+ ok = 1;
+ }
+
+ /* Skip over the number we just read */
+ while (*buf && !isspace(*buf))
+ buf++;
+
+ } while (*buf);
+
+exit:
+ kfree(msg);
+ return (ok && i == 0) ? count : -EINVAL;
+}
+
+static char const *seqname[] = {
+ "ERROR", "S5", "S3", "S0", "S5S3", "S3S0",
+ "S0S3", "S3S5", "STOP", "RUN", "KONAMI",
+ "TAP", "PROGRAM",
+};
+
+static ssize_t sequence_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ec_params_lightbar *param;
+ struct ec_response_lightbar *resp;
+ struct cros_ec_command *msg;
+ int ret;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_GET_SEQ;
+ ret = lb_throttle();
+ if (ret)
+ goto exit;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0) {
+ ret = sysfs_emit(buf, "XFER / EC ERROR %d / %d\n", ret, msg->result);
+ goto exit;
+ }
+
+ resp = (struct ec_response_lightbar *)msg->data;
+ if (resp->get_seq.num >= ARRAY_SIZE(seqname))
+ ret = sysfs_emit(buf, "%d\n", resp->get_seq.num);
+ else
+ ret = sysfs_emit(buf, "%s\n", seqname[resp->get_seq.num]);
+
+exit:
+ kfree(msg);
+ return ret;
+}
+
+static int lb_send_empty_cmd(struct cros_ec_dev *ec, uint8_t cmd)
+{
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = cmd;
+
+ ret = lb_throttle();
+ if (ret)
+ goto error;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto error;
+
+ ret = 0;
+error:
+ kfree(msg);
+
+ return ret;
+}
+
+static int lb_manual_suspend_ctrl(struct cros_ec_dev *ec, uint8_t enable)
+{
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ param = (struct ec_params_lightbar *)msg->data;
+
+ param->cmd = LIGHTBAR_CMD_MANUAL_SUSPEND_CTRL;
+ param->manual_suspend_ctrl.enable = enable;
+
+ ret = lb_throttle();
+ if (ret)
+ goto error;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto error;
+
+ ret = 0;
+error:
+ kfree(msg);
+
+ return ret;
+}
+
+static ssize_t sequence_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ unsigned int num;
+ int ret, len;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+
+ for (len = 0; len < count; len++)
+ if (!isalnum(buf[len]))
+ break;
+
+ for (num = 0; num < ARRAY_SIZE(seqname); num++)
+ if (!strncasecmp(seqname[num], buf, len))
+ break;
+
+ if (num >= ARRAY_SIZE(seqname)) {
+ ret = kstrtouint(buf, 0, &num);
+ if (ret)
+ return ret;
+ }
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_SEQ;
+ param->seq.num = num;
+ ret = lb_throttle();
+ if (ret)
+ goto exit;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto exit;
+
+ ret = count;
+exit:
+ kfree(msg);
+ return ret;
+}
+
+static ssize_t program_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int extra_bytes, max_size, ret;
+ struct ec_params_lightbar *param;
+ struct cros_ec_command *msg;
+ struct cros_ec_dev *ec = to_cros_ec_dev(dev);
+
+ /*
+ * We might need to reject the program for size reasons. The EC
+ * enforces a maximum program size, but we also don't want to try
+ * and send a program that is too big for the protocol. In order
+ * to ensure the latter, we also need to ensure we have extra bytes
+ * to represent the rest of the packet.
+ */
+ extra_bytes = sizeof(*param) - sizeof(param->set_program.data);
+ max_size = min(EC_LB_PROG_LEN, ec->ec_dev->max_request - extra_bytes);
+ if (count > max_size) {
+ dev_err(dev, "Program is %u bytes, too long to send (max: %u)",
+ (unsigned int)count, max_size);
+
+ return -EINVAL;
+ }
+
+ msg = alloc_lightbar_cmd_msg(ec);
+ if (!msg)
+ return -ENOMEM;
+
+ ret = lb_throttle();
+ if (ret)
+ goto exit;
+
+ dev_info(dev, "Copying %zu byte program to EC", count);
+
+ param = (struct ec_params_lightbar *)msg->data;
+ param->cmd = LIGHTBAR_CMD_SET_PROGRAM;
+
+ param->set_program.size = count;
+ memcpy(param->set_program.data, buf, count);
+
+ /*
+ * We need to set the message size manually or else it will use
+ * EC_LB_PROG_LEN. This might be too long, and the program
+ * is unlikely to use all of the space.
+ */
+ msg->outsize = count + extra_bytes;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+ if (ret < 0)
+ goto exit;
+
+ ret = count;
+exit:
+ kfree(msg);
+
+ return ret;
+}
+
+static ssize_t userspace_control_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sysfs_emit(buf, "%d\n", userspace_control);
+}
+
+static ssize_t userspace_control_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ bool enable;
+ int ret;
+
+ ret = kstrtobool(buf, &enable);
+ if (ret < 0)
+ return ret;
+
+ userspace_control = enable;
+
+ return count;
+}
+
+/* Module initialization */
+
+static DEVICE_ATTR_RW(interval_msec);
+static DEVICE_ATTR_RO(version);
+static DEVICE_ATTR_WO(brightness);
+static DEVICE_ATTR_WO(led_rgb);
+static DEVICE_ATTR_RW(sequence);
+static DEVICE_ATTR_WO(program);
+static DEVICE_ATTR_RW(userspace_control);
+
+static struct attribute *__lb_cmds_attrs[] = {
+ &dev_attr_interval_msec.attr,
+ &dev_attr_version.attr,
+ &dev_attr_brightness.attr,
+ &dev_attr_led_rgb.attr,
+ &dev_attr_sequence.attr,
+ &dev_attr_program.attr,
+ &dev_attr_userspace_control.attr,
+ NULL,
+};
+
+static const struct attribute_group cros_ec_lightbar_attr_group = {
+ .name = "lightbar",
+ .attrs = __lb_cmds_attrs,
+};
+
+static int cros_ec_lightbar_probe(struct platform_device *pd)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+ struct cros_ec_platform *pdata = dev_get_platdata(ec_dev->dev);
+ struct device *dev = &pd->dev;
+ int ret;
+
+ /*
+ * Only instantiate the lightbar if the EC name is 'cros_ec'. Other EC
+ * devices like 'cros_pd' doesn't have a lightbar.
+ */
+ if (strcmp(pdata->ec_name, CROS_EC_DEV_NAME) != 0)
+ return -ENODEV;
+
+ /*
+ * Ask then for the lightbar version, if it's 0 then the 'cros_ec'
+ * doesn't have a lightbar.
+ */
+ if (!get_lightbar_version(ec_dev, NULL, NULL))
+ return -ENODEV;
+
+ /* Take control of the lightbar from the EC. */
+ lb_manual_suspend_ctrl(ec_dev, 1);
+
+ ret = sysfs_create_group(&ec_dev->class_dev.kobj,
+ &cros_ec_lightbar_attr_group);
+ if (ret < 0)
+ dev_err(dev, "failed to create %s attributes. err=%d\n",
+ cros_ec_lightbar_attr_group.name, ret);
+
+ return ret;
+}
+
+static int cros_ec_lightbar_remove(struct platform_device *pd)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+
+ sysfs_remove_group(&ec_dev->class_dev.kobj,
+ &cros_ec_lightbar_attr_group);
+
+ /* Let the EC take over the lightbar again. */
+ lb_manual_suspend_ctrl(ec_dev, 0);
+
+ return 0;
+}
+
+static int __maybe_unused cros_ec_lightbar_resume(struct device *dev)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
+
+ if (userspace_control)
+ return 0;
+
+ return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_RESUME);
+}
+
+static int __maybe_unused cros_ec_lightbar_suspend(struct device *dev)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
+
+ if (userspace_control)
+ return 0;
+
+ return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_SUSPEND);
+}
+
+static SIMPLE_DEV_PM_OPS(cros_ec_lightbar_pm_ops,
+ cros_ec_lightbar_suspend, cros_ec_lightbar_resume);
+
+static struct platform_driver cros_ec_lightbar_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .pm = &cros_ec_lightbar_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+ .probe = cros_ec_lightbar_probe,
+ .remove = cros_ec_lightbar_remove,
+};
+
+module_platform_driver(cros_ec_lightbar_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Expose the Chromebook Pixel's lightbar to userspace");
+MODULE_ALIAS("platform:" DRV_NAME);