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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/gpio/gpio-aggregator.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/gpio/gpio-aggregator.c')
-rw-r--r--drivers/gpio/gpio-aggregator.c537
1 files changed, 537 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
new file mode 100644
index 000000000..6d17d262a
--- /dev/null
+++ b/drivers/gpio/gpio-aggregator.c
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// GPIO Aggregator
+//
+// Copyright (C) 2019-2020 Glider bv
+
+#define DRV_NAME "gpio-aggregator"
+#define pr_fmt(fmt) DRV_NAME ": " fmt
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/ctype.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/machine.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#define AGGREGATOR_MAX_GPIOS 512
+
+/*
+ * GPIO Aggregator sysfs interface
+ */
+
+struct gpio_aggregator {
+ struct gpiod_lookup_table *lookups;
+ struct platform_device *pdev;
+ char args[];
+};
+
+static DEFINE_MUTEX(gpio_aggregator_lock); /* protects idr */
+static DEFINE_IDR(gpio_aggregator_idr);
+
+static int aggr_add_gpio(struct gpio_aggregator *aggr, const char *key,
+ int hwnum, unsigned int *n)
+{
+ struct gpiod_lookup_table *lookups;
+
+ lookups = krealloc(aggr->lookups, struct_size(lookups, table, *n + 2),
+ GFP_KERNEL);
+ if (!lookups)
+ return -ENOMEM;
+
+ lookups->table[*n] = GPIO_LOOKUP_IDX(key, hwnum, NULL, *n, 0);
+
+ (*n)++;
+ memset(&lookups->table[*n], 0, sizeof(lookups->table[*n]));
+
+ aggr->lookups = lookups;
+ return 0;
+}
+
+static int aggr_parse(struct gpio_aggregator *aggr)
+{
+ char *args = skip_spaces(aggr->args);
+ char *name, *offsets, *p;
+ unsigned long *bitmap;
+ unsigned int i, n = 0;
+ int error = 0;
+
+ bitmap = bitmap_alloc(AGGREGATOR_MAX_GPIOS, GFP_KERNEL);
+ if (!bitmap)
+ return -ENOMEM;
+
+ args = next_arg(args, &name, &p);
+ while (*args) {
+ args = next_arg(args, &offsets, &p);
+
+ p = get_options(offsets, 0, &error);
+ if (error == 0 || *p) {
+ /* Named GPIO line */
+ error = aggr_add_gpio(aggr, name, U16_MAX, &n);
+ if (error)
+ goto free_bitmap;
+
+ name = offsets;
+ continue;
+ }
+
+ /* GPIO chip + offset(s) */
+ error = bitmap_parselist(offsets, bitmap, AGGREGATOR_MAX_GPIOS);
+ if (error) {
+ pr_err("Cannot parse %s: %d\n", offsets, error);
+ goto free_bitmap;
+ }
+
+ for_each_set_bit(i, bitmap, AGGREGATOR_MAX_GPIOS) {
+ error = aggr_add_gpio(aggr, name, i, &n);
+ if (error)
+ goto free_bitmap;
+ }
+
+ args = next_arg(args, &name, &p);
+ }
+
+ if (!n) {
+ pr_err("No GPIOs specified\n");
+ error = -EINVAL;
+ }
+
+free_bitmap:
+ bitmap_free(bitmap);
+ return error;
+}
+
+static ssize_t new_device_store(struct device_driver *driver, const char *buf,
+ size_t count)
+{
+ struct gpio_aggregator *aggr;
+ struct platform_device *pdev;
+ int res, id;
+
+ /* kernfs guarantees string termination, so count + 1 is safe */
+ aggr = kzalloc(sizeof(*aggr) + count + 1, GFP_KERNEL);
+ if (!aggr)
+ return -ENOMEM;
+
+ memcpy(aggr->args, buf, count + 1);
+
+ aggr->lookups = kzalloc(struct_size(aggr->lookups, table, 1),
+ GFP_KERNEL);
+ if (!aggr->lookups) {
+ res = -ENOMEM;
+ goto free_ga;
+ }
+
+ mutex_lock(&gpio_aggregator_lock);
+ id = idr_alloc(&gpio_aggregator_idr, aggr, 0, 0, GFP_KERNEL);
+ mutex_unlock(&gpio_aggregator_lock);
+
+ if (id < 0) {
+ res = id;
+ goto free_table;
+ }
+
+ aggr->lookups->dev_id = kasprintf(GFP_KERNEL, "%s.%d", DRV_NAME, id);
+ if (!aggr->lookups->dev_id) {
+ res = -ENOMEM;
+ goto remove_idr;
+ }
+
+ res = aggr_parse(aggr);
+ if (res)
+ goto free_dev_id;
+
+ gpiod_add_lookup_table(aggr->lookups);
+
+ pdev = platform_device_register_simple(DRV_NAME, id, NULL, 0);
+ if (IS_ERR(pdev)) {
+ res = PTR_ERR(pdev);
+ goto remove_table;
+ }
+
+ aggr->pdev = pdev;
+ return count;
+
+remove_table:
+ gpiod_remove_lookup_table(aggr->lookups);
+free_dev_id:
+ kfree(aggr->lookups->dev_id);
+remove_idr:
+ mutex_lock(&gpio_aggregator_lock);
+ idr_remove(&gpio_aggregator_idr, id);
+ mutex_unlock(&gpio_aggregator_lock);
+free_table:
+ kfree(aggr->lookups);
+free_ga:
+ kfree(aggr);
+ return res;
+}
+
+static DRIVER_ATTR_WO(new_device);
+
+static void gpio_aggregator_free(struct gpio_aggregator *aggr)
+{
+ platform_device_unregister(aggr->pdev);
+ gpiod_remove_lookup_table(aggr->lookups);
+ kfree(aggr->lookups->dev_id);
+ kfree(aggr->lookups);
+ kfree(aggr);
+}
+
+static ssize_t delete_device_store(struct device_driver *driver,
+ const char *buf, size_t count)
+{
+ struct gpio_aggregator *aggr;
+ unsigned int id;
+ int error;
+
+ if (!str_has_prefix(buf, DRV_NAME "."))
+ return -EINVAL;
+
+ error = kstrtouint(buf + strlen(DRV_NAME "."), 10, &id);
+ if (error)
+ return error;
+
+ mutex_lock(&gpio_aggregator_lock);
+ aggr = idr_remove(&gpio_aggregator_idr, id);
+ mutex_unlock(&gpio_aggregator_lock);
+ if (!aggr)
+ return -ENOENT;
+
+ gpio_aggregator_free(aggr);
+ return count;
+}
+static DRIVER_ATTR_WO(delete_device);
+
+static struct attribute *gpio_aggregator_attrs[] = {
+ &driver_attr_new_device.attr,
+ &driver_attr_delete_device.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(gpio_aggregator);
+
+static int __exit gpio_aggregator_idr_remove(int id, void *p, void *data)
+{
+ gpio_aggregator_free(p);
+ return 0;
+}
+
+static void __exit gpio_aggregator_remove_all(void)
+{
+ mutex_lock(&gpio_aggregator_lock);
+ idr_for_each(&gpio_aggregator_idr, gpio_aggregator_idr_remove, NULL);
+ idr_destroy(&gpio_aggregator_idr);
+ mutex_unlock(&gpio_aggregator_lock);
+}
+
+
+/*
+ * GPIO Forwarder
+ */
+
+struct gpiochip_fwd {
+ struct gpio_chip chip;
+ struct gpio_desc **descs;
+ union {
+ struct mutex mlock; /* protects tmp[] if can_sleep */
+ spinlock_t slock; /* protects tmp[] if !can_sleep */
+ };
+ unsigned long tmp[]; /* values and descs for multiple ops */
+};
+
+#define fwd_tmp_values(fwd) &(fwd)->tmp[0]
+#define fwd_tmp_descs(fwd) (void *)&(fwd)->tmp[BITS_TO_LONGS((fwd)->chip.ngpio)]
+
+#define fwd_tmp_size(ngpios) (BITS_TO_LONGS((ngpios)) + (ngpios))
+
+static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_get_direction(fwd->descs[offset]);
+}
+
+static int gpio_fwd_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_direction_input(fwd->descs[offset]);
+}
+
+static int gpio_fwd_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_direction_output(fwd->descs[offset], value);
+}
+
+static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return chip->can_sleep ? gpiod_get_value_cansleep(fwd->descs[offset])
+ : gpiod_get_value(fwd->descs[offset]);
+}
+
+static int gpio_fwd_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct gpio_desc **descs = fwd_tmp_descs(fwd);
+ unsigned long *values = fwd_tmp_values(fwd);
+ unsigned int i, j = 0;
+ int error;
+
+ bitmap_clear(values, 0, fwd->chip.ngpio);
+ for_each_set_bit(i, mask, fwd->chip.ngpio)
+ descs[j++] = fwd->descs[i];
+
+ if (fwd->chip.can_sleep)
+ error = gpiod_get_array_value_cansleep(j, descs, NULL, values);
+ else
+ error = gpiod_get_array_value(j, descs, NULL, values);
+ if (error)
+ return error;
+
+ j = 0;
+ for_each_set_bit(i, mask, fwd->chip.ngpio)
+ __assign_bit(i, bits, test_bit(j++, values));
+
+ return 0;
+}
+
+static int gpio_fwd_get_multiple_locked(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+ unsigned long flags;
+ int error;
+
+ if (chip->can_sleep) {
+ mutex_lock(&fwd->mlock);
+ error = gpio_fwd_get_multiple(fwd, mask, bits);
+ mutex_unlock(&fwd->mlock);
+ } else {
+ spin_lock_irqsave(&fwd->slock, flags);
+ error = gpio_fwd_get_multiple(fwd, mask, bits);
+ spin_unlock_irqrestore(&fwd->slock, flags);
+ }
+
+ return error;
+}
+
+static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ if (chip->can_sleep)
+ gpiod_set_value_cansleep(fwd->descs[offset], value);
+ else
+ gpiod_set_value(fwd->descs[offset], value);
+}
+
+static void gpio_fwd_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct gpio_desc **descs = fwd_tmp_descs(fwd);
+ unsigned long *values = fwd_tmp_values(fwd);
+ unsigned int i, j = 0;
+
+ for_each_set_bit(i, mask, fwd->chip.ngpio) {
+ __assign_bit(j, values, test_bit(i, bits));
+ descs[j++] = fwd->descs[i];
+ }
+
+ if (fwd->chip.can_sleep)
+ gpiod_set_array_value_cansleep(j, descs, NULL, values);
+ else
+ gpiod_set_array_value(j, descs, NULL, values);
+}
+
+static void gpio_fwd_set_multiple_locked(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+ unsigned long flags;
+
+ if (chip->can_sleep) {
+ mutex_lock(&fwd->mlock);
+ gpio_fwd_set_multiple(fwd, mask, bits);
+ mutex_unlock(&fwd->mlock);
+ } else {
+ spin_lock_irqsave(&fwd->slock, flags);
+ gpio_fwd_set_multiple(fwd, mask, bits);
+ spin_unlock_irqrestore(&fwd->slock, flags);
+ }
+}
+
+static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset,
+ unsigned long config)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_set_config(fwd->descs[offset], config);
+}
+
+static int gpio_fwd_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_to_irq(fwd->descs[offset]);
+}
+
+/**
+ * gpiochip_fwd_create() - Create a new GPIO forwarder
+ * @dev: Parent device pointer
+ * @ngpios: Number of GPIOs in the forwarder.
+ * @descs: Array containing the GPIO descriptors to forward to.
+ * This array must contain @ngpios entries, and must not be deallocated
+ * before the forwarder has been destroyed again.
+ *
+ * This function creates a new gpiochip, which forwards all GPIO operations to
+ * the passed GPIO descriptors.
+ *
+ * Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
+ * code on failure.
+ */
+static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
+ unsigned int ngpios,
+ struct gpio_desc *descs[])
+{
+ const char *label = dev_name(dev);
+ struct gpiochip_fwd *fwd;
+ struct gpio_chip *chip;
+ unsigned int i;
+ int error;
+
+ fwd = devm_kzalloc(dev, struct_size(fwd, tmp, fwd_tmp_size(ngpios)),
+ GFP_KERNEL);
+ if (!fwd)
+ return ERR_PTR(-ENOMEM);
+
+ chip = &fwd->chip;
+
+ /*
+ * If any of the GPIO lines are sleeping, then the entire forwarder
+ * will be sleeping.
+ * If any of the chips support .set_config(), then the forwarder will
+ * support setting configs.
+ */
+ for (i = 0; i < ngpios; i++) {
+ struct gpio_chip *parent = gpiod_to_chip(descs[i]);
+
+ dev_dbg(dev, "%u => gpio %d irq %d\n", i,
+ desc_to_gpio(descs[i]), gpiod_to_irq(descs[i]));
+
+ if (gpiod_cansleep(descs[i]))
+ chip->can_sleep = true;
+ if (parent && parent->set_config)
+ chip->set_config = gpio_fwd_set_config;
+ }
+
+ chip->label = label;
+ chip->parent = dev;
+ chip->owner = THIS_MODULE;
+ chip->get_direction = gpio_fwd_get_direction;
+ chip->direction_input = gpio_fwd_direction_input;
+ chip->direction_output = gpio_fwd_direction_output;
+ chip->get = gpio_fwd_get;
+ chip->get_multiple = gpio_fwd_get_multiple_locked;
+ chip->set = gpio_fwd_set;
+ chip->set_multiple = gpio_fwd_set_multiple_locked;
+ chip->to_irq = gpio_fwd_to_irq;
+ chip->base = -1;
+ chip->ngpio = ngpios;
+ fwd->descs = descs;
+
+ if (chip->can_sleep)
+ mutex_init(&fwd->mlock);
+ else
+ spin_lock_init(&fwd->slock);
+
+ error = devm_gpiochip_add_data(dev, chip, fwd);
+ if (error)
+ return ERR_PTR(error);
+
+ return fwd;
+}
+
+
+/*
+ * GPIO Aggregator platform device
+ */
+
+static int gpio_aggregator_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct gpio_desc **descs;
+ struct gpiochip_fwd *fwd;
+ int i, n;
+
+ n = gpiod_count(dev, NULL);
+ if (n < 0)
+ return n;
+
+ descs = devm_kmalloc_array(dev, n, sizeof(*descs), GFP_KERNEL);
+ if (!descs)
+ return -ENOMEM;
+
+ for (i = 0; i < n; i++) {
+ descs[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
+ if (IS_ERR(descs[i]))
+ return PTR_ERR(descs[i]);
+ }
+
+ fwd = gpiochip_fwd_create(dev, n, descs);
+ if (IS_ERR(fwd))
+ return PTR_ERR(fwd);
+
+ platform_set_drvdata(pdev, fwd);
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_aggregator_dt_ids[] = {
+ /*
+ * Add GPIO-operated devices controlled from userspace below,
+ * or use "driver_override" in sysfs
+ */
+ {}
+};
+MODULE_DEVICE_TABLE(of, gpio_aggregator_dt_ids);
+#endif
+
+static struct platform_driver gpio_aggregator_driver = {
+ .probe = gpio_aggregator_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .groups = gpio_aggregator_groups,
+ .of_match_table = of_match_ptr(gpio_aggregator_dt_ids),
+ },
+};
+
+static int __init gpio_aggregator_init(void)
+{
+ return platform_driver_register(&gpio_aggregator_driver);
+}
+module_init(gpio_aggregator_init);
+
+static void __exit gpio_aggregator_exit(void)
+{
+ gpio_aggregator_remove_all();
+ platform_driver_unregister(&gpio_aggregator_driver);
+}
+module_exit(gpio_aggregator_exit);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
+MODULE_DESCRIPTION("GPIO Aggregator");
+MODULE_LICENSE("GPL v2");