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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/hwmon/gpio-fan.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/hwmon/gpio-fan.c')
-rw-r--r--drivers/hwmon/gpio-fan.c598
1 files changed, 598 insertions, 0 deletions
diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c
new file mode 100644
index 000000000..e75db6f64
--- /dev/null
+++ b/drivers/hwmon/gpio-fan.c
@@ -0,0 +1,598 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * gpio-fan.c - Hwmon driver for fans connected to GPIO lines.
+ *
+ * Copyright (C) 2010 LaCie
+ *
+ * Author: Simon Guinot <sguinot@lacie.com>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/kstrtox.h>
+#include <linux/mutex.h>
+#include <linux/hwmon.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/thermal.h>
+
+struct gpio_fan_speed {
+ int rpm;
+ int ctrl_val;
+};
+
+struct gpio_fan_data {
+ struct device *dev;
+ struct device *hwmon_dev;
+ /* Cooling device if any */
+ struct thermal_cooling_device *cdev;
+ struct mutex lock; /* lock GPIOs operations. */
+ int num_gpios;
+ struct gpio_desc **gpios;
+ int num_speed;
+ struct gpio_fan_speed *speed;
+ int speed_index;
+ int resume_speed;
+ bool pwm_enable;
+ struct gpio_desc *alarm_gpio;
+ struct work_struct alarm_work;
+};
+
+/*
+ * Alarm GPIO.
+ */
+
+static void fan_alarm_notify(struct work_struct *ws)
+{
+ struct gpio_fan_data *fan_data =
+ container_of(ws, struct gpio_fan_data, alarm_work);
+
+ sysfs_notify(&fan_data->hwmon_dev->kobj, NULL, "fan1_alarm");
+ kobject_uevent(&fan_data->hwmon_dev->kobj, KOBJ_CHANGE);
+}
+
+static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
+{
+ struct gpio_fan_data *fan_data = dev_id;
+
+ schedule_work(&fan_data->alarm_work);
+
+ return IRQ_NONE;
+}
+
+static ssize_t fan1_alarm_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n",
+ gpiod_get_value_cansleep(fan_data->alarm_gpio));
+}
+
+static DEVICE_ATTR_RO(fan1_alarm);
+
+static int fan_alarm_init(struct gpio_fan_data *fan_data)
+{
+ int alarm_irq;
+ struct device *dev = fan_data->dev;
+
+ /*
+ * If the alarm GPIO don't support interrupts, just leave
+ * without initializing the fail notification support.
+ */
+ alarm_irq = gpiod_to_irq(fan_data->alarm_gpio);
+ if (alarm_irq <= 0)
+ return 0;
+
+ INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);
+ irq_set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
+ return devm_request_irq(dev, alarm_irq, fan_alarm_irq_handler,
+ IRQF_SHARED, "GPIO fan alarm", fan_data);
+}
+
+/*
+ * Control GPIOs.
+ */
+
+/* Must be called with fan_data->lock held, except during initialization. */
+static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
+{
+ int i;
+
+ for (i = 0; i < fan_data->num_gpios; i++)
+ gpiod_set_value_cansleep(fan_data->gpios[i],
+ (ctrl_val >> i) & 1);
+}
+
+static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
+{
+ int i;
+ int ctrl_val = 0;
+
+ for (i = 0; i < fan_data->num_gpios; i++) {
+ int value;
+
+ value = gpiod_get_value_cansleep(fan_data->gpios[i]);
+ ctrl_val |= (value << i);
+ }
+ return ctrl_val;
+}
+
+/* Must be called with fan_data->lock held, except during initialization. */
+static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
+{
+ if (fan_data->speed_index == speed_index)
+ return;
+
+ __set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
+ fan_data->speed_index = speed_index;
+}
+
+static int get_fan_speed_index(struct gpio_fan_data *fan_data)
+{
+ int ctrl_val = __get_fan_ctrl(fan_data);
+ int i;
+
+ for (i = 0; i < fan_data->num_speed; i++)
+ if (fan_data->speed[i].ctrl_val == ctrl_val)
+ return i;
+
+ dev_warn(fan_data->dev,
+ "missing speed array entry for GPIO value 0x%x\n", ctrl_val);
+
+ return -ENODEV;
+}
+
+static int rpm_to_speed_index(struct gpio_fan_data *fan_data, unsigned long rpm)
+{
+ struct gpio_fan_speed *speed = fan_data->speed;
+ int i;
+
+ for (i = 0; i < fan_data->num_speed; i++)
+ if (speed[i].rpm >= rpm)
+ return i;
+
+ return fan_data->num_speed - 1;
+}
+
+static ssize_t pwm1_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+ u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
+
+ return sprintf(buf, "%d\n", pwm);
+}
+
+static ssize_t pwm1_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+ unsigned long pwm;
+ int speed_index;
+ int ret = count;
+
+ if (kstrtoul(buf, 10, &pwm) || pwm > 255)
+ return -EINVAL;
+
+ mutex_lock(&fan_data->lock);
+
+ if (!fan_data->pwm_enable) {
+ ret = -EPERM;
+ goto exit_unlock;
+ }
+
+ speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
+ set_fan_speed(fan_data, speed_index);
+
+exit_unlock:
+ mutex_unlock(&fan_data->lock);
+
+ return ret;
+}
+
+static ssize_t pwm1_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", fan_data->pwm_enable);
+}
+
+static ssize_t pwm1_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val) || val > 1)
+ return -EINVAL;
+
+ if (fan_data->pwm_enable == val)
+ return count;
+
+ mutex_lock(&fan_data->lock);
+
+ fan_data->pwm_enable = val;
+
+ /* Disable manual control mode: set fan at full speed. */
+ if (val == 0)
+ set_fan_speed(fan_data, fan_data->num_speed - 1);
+
+ mutex_unlock(&fan_data->lock);
+
+ return count;
+}
+
+static ssize_t pwm1_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0\n");
+}
+
+static ssize_t fan1_min_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
+}
+
+static ssize_t fan1_max_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n",
+ fan_data->speed[fan_data->num_speed - 1].rpm);
+}
+
+static ssize_t fan1_input_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
+}
+
+static ssize_t set_rpm(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+ unsigned long rpm;
+ int ret = count;
+
+ if (kstrtoul(buf, 10, &rpm))
+ return -EINVAL;
+
+ mutex_lock(&fan_data->lock);
+
+ if (!fan_data->pwm_enable) {
+ ret = -EPERM;
+ goto exit_unlock;
+ }
+
+ set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
+
+exit_unlock:
+ mutex_unlock(&fan_data->lock);
+
+ return ret;
+}
+
+static DEVICE_ATTR_RW(pwm1);
+static DEVICE_ATTR_RW(pwm1_enable);
+static DEVICE_ATTR_RO(pwm1_mode);
+static DEVICE_ATTR_RO(fan1_min);
+static DEVICE_ATTR_RO(fan1_max);
+static DEVICE_ATTR_RO(fan1_input);
+static DEVICE_ATTR(fan1_target, 0644, fan1_input_show, set_rpm);
+
+static umode_t gpio_fan_is_visible(struct kobject *kobj,
+ struct attribute *attr, int index)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct gpio_fan_data *data = dev_get_drvdata(dev);
+
+ if (index == 0 && !data->alarm_gpio)
+ return 0;
+ if (index > 0 && !data->gpios)
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute *gpio_fan_attributes[] = {
+ &dev_attr_fan1_alarm.attr, /* 0 */
+ &dev_attr_pwm1.attr, /* 1 */
+ &dev_attr_pwm1_enable.attr,
+ &dev_attr_pwm1_mode.attr,
+ &dev_attr_fan1_input.attr,
+ &dev_attr_fan1_target.attr,
+ &dev_attr_fan1_min.attr,
+ &dev_attr_fan1_max.attr,
+ NULL
+};
+
+static const struct attribute_group gpio_fan_group = {
+ .attrs = gpio_fan_attributes,
+ .is_visible = gpio_fan_is_visible,
+};
+
+static const struct attribute_group *gpio_fan_groups[] = {
+ &gpio_fan_group,
+ NULL
+};
+
+static int fan_ctrl_init(struct gpio_fan_data *fan_data)
+{
+ int num_gpios = fan_data->num_gpios;
+ struct gpio_desc **gpios = fan_data->gpios;
+ int i, err;
+
+ for (i = 0; i < num_gpios; i++) {
+ /*
+ * The GPIO descriptors were retrieved with GPIOD_ASIS so here
+ * we set the GPIO into output mode, carefully preserving the
+ * current value by setting it to whatever it is already set
+ * (no surprise changes in default fan speed).
+ */
+ err = gpiod_direction_output(gpios[i],
+ gpiod_get_value_cansleep(gpios[i]));
+ if (err)
+ return err;
+ }
+
+ fan_data->pwm_enable = true; /* Enable manual fan speed control. */
+ fan_data->speed_index = get_fan_speed_index(fan_data);
+ if (fan_data->speed_index < 0)
+ return fan_data->speed_index;
+
+ return 0;
+}
+
+static int gpio_fan_get_max_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct gpio_fan_data *fan_data = cdev->devdata;
+
+ if (!fan_data)
+ return -EINVAL;
+
+ *state = fan_data->num_speed - 1;
+ return 0;
+}
+
+static int gpio_fan_get_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct gpio_fan_data *fan_data = cdev->devdata;
+
+ if (!fan_data)
+ return -EINVAL;
+
+ *state = fan_data->speed_index;
+ return 0;
+}
+
+static int gpio_fan_set_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long state)
+{
+ struct gpio_fan_data *fan_data = cdev->devdata;
+
+ if (!fan_data)
+ return -EINVAL;
+
+ if (state >= fan_data->num_speed)
+ return -EINVAL;
+
+ set_fan_speed(fan_data, state);
+ return 0;
+}
+
+static const struct thermal_cooling_device_ops gpio_fan_cool_ops = {
+ .get_max_state = gpio_fan_get_max_state,
+ .get_cur_state = gpio_fan_get_cur_state,
+ .set_cur_state = gpio_fan_set_cur_state,
+};
+
+/*
+ * Translate OpenFirmware node properties into platform_data
+ */
+static int gpio_fan_get_of_data(struct gpio_fan_data *fan_data)
+{
+ struct gpio_fan_speed *speed;
+ struct device *dev = fan_data->dev;
+ struct device_node *np = dev->of_node;
+ struct gpio_desc **gpios;
+ unsigned i;
+ u32 u;
+ struct property *prop;
+ const __be32 *p;
+
+ /* Alarm GPIO if one exists */
+ fan_data->alarm_gpio = devm_gpiod_get_optional(dev, "alarm", GPIOD_IN);
+ if (IS_ERR(fan_data->alarm_gpio))
+ return PTR_ERR(fan_data->alarm_gpio);
+
+ /* Fill GPIO pin array */
+ fan_data->num_gpios = gpiod_count(dev, NULL);
+ if (fan_data->num_gpios <= 0) {
+ if (fan_data->alarm_gpio)
+ return 0;
+ dev_err(dev, "DT properties empty / missing");
+ return -ENODEV;
+ }
+ gpios = devm_kcalloc(dev,
+ fan_data->num_gpios, sizeof(struct gpio_desc *),
+ GFP_KERNEL);
+ if (!gpios)
+ return -ENOMEM;
+ for (i = 0; i < fan_data->num_gpios; i++) {
+ gpios[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
+ if (IS_ERR(gpios[i]))
+ return PTR_ERR(gpios[i]);
+ }
+ fan_data->gpios = gpios;
+
+ /* Get number of RPM/ctrl_val pairs in speed map */
+ prop = of_find_property(np, "gpio-fan,speed-map", &i);
+ if (!prop) {
+ dev_err(dev, "gpio-fan,speed-map DT property missing");
+ return -ENODEV;
+ }
+ i = i / sizeof(u32);
+ if (i == 0 || i & 1) {
+ dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");
+ return -ENODEV;
+ }
+ fan_data->num_speed = i / 2;
+
+ /*
+ * Populate speed map
+ * Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>
+ * this needs splitting into pairs to create gpio_fan_speed structs
+ */
+ speed = devm_kcalloc(dev,
+ fan_data->num_speed, sizeof(struct gpio_fan_speed),
+ GFP_KERNEL);
+ if (!speed)
+ return -ENOMEM;
+ p = NULL;
+ for (i = 0; i < fan_data->num_speed; i++) {
+ p = of_prop_next_u32(prop, p, &u);
+ if (!p)
+ return -ENODEV;
+ speed[i].rpm = u;
+ p = of_prop_next_u32(prop, p, &u);
+ if (!p)
+ return -ENODEV;
+ speed[i].ctrl_val = u;
+ }
+ fan_data->speed = speed;
+
+ return 0;
+}
+
+static const struct of_device_id of_gpio_fan_match[] = {
+ { .compatible = "gpio-fan", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_gpio_fan_match);
+
+static void gpio_fan_stop(void *data)
+{
+ set_fan_speed(data, 0);
+}
+
+static int gpio_fan_probe(struct platform_device *pdev)
+{
+ int err;
+ struct gpio_fan_data *fan_data;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+
+ fan_data = devm_kzalloc(dev, sizeof(struct gpio_fan_data),
+ GFP_KERNEL);
+ if (!fan_data)
+ return -ENOMEM;
+
+ fan_data->dev = dev;
+ err = gpio_fan_get_of_data(fan_data);
+ if (err)
+ return err;
+
+ platform_set_drvdata(pdev, fan_data);
+ mutex_init(&fan_data->lock);
+
+ /* Configure control GPIOs if available. */
+ if (fan_data->gpios && fan_data->num_gpios > 0) {
+ if (!fan_data->speed || fan_data->num_speed <= 1)
+ return -EINVAL;
+ err = fan_ctrl_init(fan_data);
+ if (err)
+ return err;
+ err = devm_add_action_or_reset(dev, gpio_fan_stop, fan_data);
+ if (err)
+ return err;
+ }
+
+ /* Make this driver part of hwmon class. */
+ fan_data->hwmon_dev =
+ devm_hwmon_device_register_with_groups(dev,
+ "gpio_fan", fan_data,
+ gpio_fan_groups);
+ if (IS_ERR(fan_data->hwmon_dev))
+ return PTR_ERR(fan_data->hwmon_dev);
+
+ /* Configure alarm GPIO if available. */
+ if (fan_data->alarm_gpio) {
+ err = fan_alarm_init(fan_data);
+ if (err)
+ return err;
+ }
+
+ /* Optional cooling device register for Device tree platforms */
+ fan_data->cdev = devm_thermal_of_cooling_device_register(dev, np,
+ "gpio-fan", fan_data, &gpio_fan_cool_ops);
+
+ dev_info(dev, "GPIO fan initialized\n");
+
+ return 0;
+}
+
+static void gpio_fan_shutdown(struct platform_device *pdev)
+{
+ struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
+
+ if (fan_data->gpios)
+ set_fan_speed(fan_data, 0);
+}
+
+static int gpio_fan_suspend(struct device *dev)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ if (fan_data->gpios) {
+ fan_data->resume_speed = fan_data->speed_index;
+ set_fan_speed(fan_data, 0);
+ }
+
+ return 0;
+}
+
+static int gpio_fan_resume(struct device *dev)
+{
+ struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
+
+ if (fan_data->gpios)
+ set_fan_speed(fan_data, fan_data->resume_speed);
+
+ return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume);
+
+static struct platform_driver gpio_fan_driver = {
+ .probe = gpio_fan_probe,
+ .shutdown = gpio_fan_shutdown,
+ .driver = {
+ .name = "gpio-fan",
+ .pm = pm_sleep_ptr(&gpio_fan_pm),
+ .of_match_table = of_match_ptr(of_gpio_fan_match),
+ },
+};
+
+module_platform_driver(gpio_fan_driver);
+
+MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
+MODULE_DESCRIPTION("GPIO FAN driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio-fan");