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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/i2c/i2c-stub.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/i2c/i2c-stub.c')
-rw-r--r--drivers/i2c/i2c-stub.c413
1 files changed, 413 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-stub.c b/drivers/i2c/i2c-stub.c
new file mode 100644
index 000000000..d642cad21
--- /dev/null
+++ b/drivers/i2c/i2c-stub.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ i2c-stub.c - I2C/SMBus chip emulator
+
+ Copyright (c) 2004 Mark M. Hoffman <mhoffman@lightlink.com>
+ Copyright (C) 2007-2014 Jean Delvare <jdelvare@suse.de>
+
+*/
+
+#define pr_fmt(fmt) "i2c-stub: " fmt
+
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#define MAX_CHIPS 10
+
+/*
+ * Support for I2C_FUNC_SMBUS_BLOCK_DATA is disabled by default and must
+ * be enabled explicitly by setting the I2C_FUNC_SMBUS_BLOCK_DATA bits
+ * in the 'functionality' module parameter.
+ */
+#define STUB_FUNC_DEFAULT \
+ (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | \
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | \
+ I2C_FUNC_SMBUS_I2C_BLOCK)
+
+#define STUB_FUNC_ALL \
+ (STUB_FUNC_DEFAULT | I2C_FUNC_SMBUS_BLOCK_DATA)
+
+static unsigned short chip_addr[MAX_CHIPS];
+module_param_array(chip_addr, ushort, NULL, S_IRUGO);
+MODULE_PARM_DESC(chip_addr,
+ "Chip addresses (up to 10, between 0x03 and 0x77)");
+
+static unsigned long functionality = STUB_FUNC_DEFAULT;
+module_param(functionality, ulong, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(functionality, "Override functionality bitfield");
+
+/* Some chips have banked register ranges */
+
+static u8 bank_reg[MAX_CHIPS];
+module_param_array(bank_reg, byte, NULL, S_IRUGO);
+MODULE_PARM_DESC(bank_reg, "Bank register");
+
+static u8 bank_mask[MAX_CHIPS];
+module_param_array(bank_mask, byte, NULL, S_IRUGO);
+MODULE_PARM_DESC(bank_mask, "Bank value mask");
+
+static u8 bank_start[MAX_CHIPS];
+module_param_array(bank_start, byte, NULL, S_IRUGO);
+MODULE_PARM_DESC(bank_start, "First banked register");
+
+static u8 bank_end[MAX_CHIPS];
+module_param_array(bank_end, byte, NULL, S_IRUGO);
+MODULE_PARM_DESC(bank_end, "Last banked register");
+
+struct smbus_block_data {
+ struct list_head node;
+ u8 command;
+ u8 len;
+ u8 block[I2C_SMBUS_BLOCK_MAX];
+};
+
+struct stub_chip {
+ u8 pointer;
+ u16 words[256]; /* Byte operations use the LSB as per SMBus
+ specification */
+ struct list_head smbus_blocks;
+
+ /* For chips with banks, extra registers are allocated dynamically */
+ u8 bank_reg;
+ u8 bank_shift;
+ u8 bank_mask;
+ u8 bank_sel; /* Currently selected bank */
+ u8 bank_start;
+ u8 bank_end;
+ u16 bank_size;
+ u16 *bank_words; /* Room for bank_mask * bank_size registers */
+};
+
+static struct stub_chip *stub_chips;
+static int stub_chips_nr;
+
+static struct smbus_block_data *stub_find_block(struct device *dev,
+ struct stub_chip *chip,
+ u8 command, bool create)
+{
+ struct smbus_block_data *b, *rb = NULL;
+
+ list_for_each_entry(b, &chip->smbus_blocks, node) {
+ if (b->command == command) {
+ rb = b;
+ break;
+ }
+ }
+ if (rb == NULL && create) {
+ rb = devm_kzalloc(dev, sizeof(*rb), GFP_KERNEL);
+ if (rb == NULL)
+ return rb;
+ rb->command = command;
+ list_add(&rb->node, &chip->smbus_blocks);
+ }
+ return rb;
+}
+
+static u16 *stub_get_wordp(struct stub_chip *chip, u8 offset)
+{
+ if (chip->bank_sel &&
+ offset >= chip->bank_start && offset <= chip->bank_end)
+ return chip->bank_words +
+ (chip->bank_sel - 1) * chip->bank_size +
+ offset - chip->bank_start;
+ else
+ return chip->words + offset;
+}
+
+/* Return negative errno on error. */
+static s32 stub_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags,
+ char read_write, u8 command, int size, union i2c_smbus_data *data)
+{
+ s32 ret;
+ int i, len;
+ struct stub_chip *chip = NULL;
+ struct smbus_block_data *b;
+ u16 *wordp;
+
+ /* Search for the right chip */
+ for (i = 0; i < stub_chips_nr; i++) {
+ if (addr == chip_addr[i]) {
+ chip = stub_chips + i;
+ break;
+ }
+ }
+ if (!chip)
+ return -ENODEV;
+
+ switch (size) {
+
+ case I2C_SMBUS_QUICK:
+ dev_dbg(&adap->dev, "smbus quick - addr 0x%02x\n", addr);
+ ret = 0;
+ break;
+
+ case I2C_SMBUS_BYTE:
+ if (read_write == I2C_SMBUS_WRITE) {
+ chip->pointer = command;
+ dev_dbg(&adap->dev,
+ "smbus byte - addr 0x%02x, wrote 0x%02x.\n",
+ addr, command);
+ } else {
+ wordp = stub_get_wordp(chip, chip->pointer++);
+ data->byte = *wordp & 0xff;
+ dev_dbg(&adap->dev,
+ "smbus byte - addr 0x%02x, read 0x%02x.\n",
+ addr, data->byte);
+ }
+
+ ret = 0;
+ break;
+
+ case I2C_SMBUS_BYTE_DATA:
+ wordp = stub_get_wordp(chip, command);
+ if (read_write == I2C_SMBUS_WRITE) {
+ *wordp &= 0xff00;
+ *wordp |= data->byte;
+ dev_dbg(&adap->dev,
+ "smbus byte data - addr 0x%02x, wrote 0x%02x at 0x%02x.\n",
+ addr, data->byte, command);
+
+ /* Set the bank as needed */
+ if (chip->bank_words && command == chip->bank_reg) {
+ chip->bank_sel =
+ (data->byte >> chip->bank_shift)
+ & chip->bank_mask;
+ dev_dbg(&adap->dev,
+ "switching to bank %u.\n",
+ chip->bank_sel);
+ }
+ } else {
+ data->byte = *wordp & 0xff;
+ dev_dbg(&adap->dev,
+ "smbus byte data - addr 0x%02x, read 0x%02x at 0x%02x.\n",
+ addr, data->byte, command);
+ }
+ chip->pointer = command + 1;
+
+ ret = 0;
+ break;
+
+ case I2C_SMBUS_WORD_DATA:
+ wordp = stub_get_wordp(chip, command);
+ if (read_write == I2C_SMBUS_WRITE) {
+ *wordp = data->word;
+ dev_dbg(&adap->dev,
+ "smbus word data - addr 0x%02x, wrote 0x%04x at 0x%02x.\n",
+ addr, data->word, command);
+ } else {
+ data->word = *wordp;
+ dev_dbg(&adap->dev,
+ "smbus word data - addr 0x%02x, read 0x%04x at 0x%02x.\n",
+ addr, data->word, command);
+ }
+
+ ret = 0;
+ break;
+
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ /*
+ * We ignore banks here, because banked chips don't use I2C
+ * block transfers
+ */
+ if (data->block[0] > 256 - command) /* Avoid overrun */
+ data->block[0] = 256 - command;
+ len = data->block[0];
+ if (read_write == I2C_SMBUS_WRITE) {
+ for (i = 0; i < len; i++) {
+ chip->words[command + i] &= 0xff00;
+ chip->words[command + i] |= data->block[1 + i];
+ }
+ dev_dbg(&adap->dev,
+ "i2c block data - addr 0x%02x, wrote %d bytes at 0x%02x.\n",
+ addr, len, command);
+ } else {
+ for (i = 0; i < len; i++) {
+ data->block[1 + i] =
+ chip->words[command + i] & 0xff;
+ }
+ dev_dbg(&adap->dev,
+ "i2c block data - addr 0x%02x, read %d bytes at 0x%02x.\n",
+ addr, len, command);
+ }
+
+ ret = 0;
+ break;
+
+ case I2C_SMBUS_BLOCK_DATA:
+ /*
+ * We ignore banks here, because chips typically don't use both
+ * banks and SMBus block transfers
+ */
+ b = stub_find_block(&adap->dev, chip, command, false);
+ if (read_write == I2C_SMBUS_WRITE) {
+ len = data->block[0];
+ if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) {
+ ret = -EINVAL;
+ break;
+ }
+ if (b == NULL) {
+ b = stub_find_block(&adap->dev, chip, command,
+ true);
+ if (b == NULL) {
+ ret = -ENOMEM;
+ break;
+ }
+ }
+ /* Largest write sets read block length */
+ if (len > b->len)
+ b->len = len;
+ for (i = 0; i < len; i++)
+ b->block[i] = data->block[i + 1];
+ /* update for byte and word commands */
+ chip->words[command] = (b->block[0] << 8) | b->len;
+ dev_dbg(&adap->dev,
+ "smbus block data - addr 0x%02x, wrote %d bytes at 0x%02x.\n",
+ addr, len, command);
+ } else {
+ if (b == NULL) {
+ dev_dbg(&adap->dev,
+ "SMBus block read command without prior block write not supported\n");
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ len = b->len;
+ data->block[0] = len;
+ for (i = 0; i < len; i++)
+ data->block[i + 1] = b->block[i];
+ dev_dbg(&adap->dev,
+ "smbus block data - addr 0x%02x, read %d bytes at 0x%02x.\n",
+ addr, len, command);
+ }
+
+ ret = 0;
+ break;
+
+ default:
+ dev_dbg(&adap->dev, "Unsupported I2C/SMBus command\n");
+ ret = -EOPNOTSUPP;
+ break;
+ } /* switch (size) */
+
+ return ret;
+}
+
+static u32 stub_func(struct i2c_adapter *adapter)
+{
+ return STUB_FUNC_ALL & functionality;
+}
+
+static const struct i2c_algorithm smbus_algorithm = {
+ .functionality = stub_func,
+ .smbus_xfer = stub_xfer,
+};
+
+static struct i2c_adapter stub_adapter = {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .algo = &smbus_algorithm,
+ .name = "SMBus stub driver",
+};
+
+static int __init i2c_stub_allocate_banks(int i)
+{
+ struct stub_chip *chip = stub_chips + i;
+
+ chip->bank_reg = bank_reg[i];
+ chip->bank_start = bank_start[i];
+ chip->bank_end = bank_end[i];
+ chip->bank_size = bank_end[i] - bank_start[i] + 1;
+
+ /* We assume that all bits in the mask are contiguous */
+ chip->bank_mask = bank_mask[i];
+ while (!(chip->bank_mask & 1)) {
+ chip->bank_shift++;
+ chip->bank_mask >>= 1;
+ }
+
+ chip->bank_words = kcalloc(chip->bank_mask * chip->bank_size,
+ sizeof(u16),
+ GFP_KERNEL);
+ if (!chip->bank_words)
+ return -ENOMEM;
+
+ pr_debug("Allocated %u banks of %u words each (registers 0x%02x to 0x%02x)\n",
+ chip->bank_mask, chip->bank_size, chip->bank_start,
+ chip->bank_end);
+
+ return 0;
+}
+
+static void i2c_stub_free(void)
+{
+ int i;
+
+ for (i = 0; i < stub_chips_nr; i++)
+ kfree(stub_chips[i].bank_words);
+ kfree(stub_chips);
+}
+
+static int __init i2c_stub_init(void)
+{
+ int i, ret;
+
+ if (!chip_addr[0]) {
+ pr_err("Please specify a chip address\n");
+ return -ENODEV;
+ }
+
+ for (i = 0; i < MAX_CHIPS && chip_addr[i]; i++) {
+ if (chip_addr[i] < 0x03 || chip_addr[i] > 0x77) {
+ pr_err("Invalid chip address 0x%02x\n",
+ chip_addr[i]);
+ return -EINVAL;
+ }
+
+ pr_info("Virtual chip at 0x%02x\n", chip_addr[i]);
+ }
+
+ /* Allocate memory for all chips at once */
+ stub_chips_nr = i;
+ stub_chips = kcalloc(stub_chips_nr, sizeof(struct stub_chip),
+ GFP_KERNEL);
+ if (!stub_chips)
+ return -ENOMEM;
+
+ for (i = 0; i < stub_chips_nr; i++) {
+ INIT_LIST_HEAD(&stub_chips[i].smbus_blocks);
+
+ /* Allocate extra memory for banked register ranges */
+ if (bank_mask[i]) {
+ ret = i2c_stub_allocate_banks(i);
+ if (ret)
+ goto fail_free;
+ }
+ }
+
+ ret = i2c_add_adapter(&stub_adapter);
+ if (ret)
+ goto fail_free;
+
+ return 0;
+
+ fail_free:
+ i2c_stub_free();
+ return ret;
+}
+
+static void __exit i2c_stub_exit(void)
+{
+ i2c_del_adapter(&stub_adapter);
+ i2c_stub_free();
+}
+
+MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
+MODULE_DESCRIPTION("I2C stub driver");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_stub_init);
+module_exit(i2c_stub_exit);