From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/i2c/busses/i2c-fsi.c | 776 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 776 insertions(+) create mode 100644 drivers/i2c/busses/i2c-fsi.c (limited to 'drivers/i2c/busses/i2c-fsi.c') diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c new file mode 100644 index 000000000..10332693e --- /dev/null +++ b/drivers/i2c/busses/i2c-fsi.c @@ -0,0 +1,776 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * FSI-attached I2C master algorithm + * + * Copyright 2018 IBM Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define FSI_ENGID_I2C 0x7 + +#define I2C_DEFAULT_CLK_DIV 6 + +/* i2c registers */ +#define I2C_FSI_FIFO 0x00 +#define I2C_FSI_CMD 0x04 +#define I2C_FSI_MODE 0x08 +#define I2C_FSI_WATER_MARK 0x0C +#define I2C_FSI_INT_MASK 0x10 +#define I2C_FSI_INT_COND 0x14 +#define I2C_FSI_OR_INT_MASK 0x14 +#define I2C_FSI_INTS 0x18 +#define I2C_FSI_AND_INT_MASK 0x18 +#define I2C_FSI_STAT 0x1C +#define I2C_FSI_RESET_I2C 0x1C +#define I2C_FSI_ESTAT 0x20 +#define I2C_FSI_RESET_ERR 0x20 +#define I2C_FSI_RESID_LEN 0x24 +#define I2C_FSI_SET_SCL 0x24 +#define I2C_FSI_PORT_BUSY 0x28 +#define I2C_FSI_RESET_SCL 0x2C +#define I2C_FSI_SET_SDA 0x30 +#define I2C_FSI_RESET_SDA 0x34 + +/* cmd register */ +#define I2C_CMD_WITH_START BIT(31) +#define I2C_CMD_WITH_ADDR BIT(30) +#define I2C_CMD_RD_CONT BIT(29) +#define I2C_CMD_WITH_STOP BIT(28) +#define I2C_CMD_FORCELAUNCH BIT(27) +#define I2C_CMD_ADDR GENMASK(23, 17) +#define I2C_CMD_READ BIT(16) +#define I2C_CMD_LEN GENMASK(15, 0) + +/* mode register */ +#define I2C_MODE_CLKDIV GENMASK(31, 16) +#define I2C_MODE_PORT GENMASK(15, 10) +#define I2C_MODE_ENHANCED BIT(3) +#define I2C_MODE_DIAG BIT(2) +#define I2C_MODE_PACE_ALLOW BIT(1) +#define I2C_MODE_WRAP BIT(0) + +/* watermark register */ +#define I2C_WATERMARK_HI GENMASK(15, 12) +#define I2C_WATERMARK_LO GENMASK(7, 4) + +#define I2C_FIFO_HI_LVL 4 +#define I2C_FIFO_LO_LVL 4 + +/* interrupt register */ +#define I2C_INT_INV_CMD BIT(15) +#define I2C_INT_PARITY BIT(14) +#define I2C_INT_BE_OVERRUN BIT(13) +#define I2C_INT_BE_ACCESS BIT(12) +#define I2C_INT_LOST_ARB BIT(11) +#define I2C_INT_NACK BIT(10) +#define I2C_INT_DAT_REQ BIT(9) +#define I2C_INT_CMD_COMP BIT(8) +#define I2C_INT_STOP_ERR BIT(7) +#define I2C_INT_BUSY BIT(6) +#define I2C_INT_IDLE BIT(5) + +/* status register */ +#define I2C_STAT_INV_CMD BIT(31) +#define I2C_STAT_PARITY BIT(30) +#define I2C_STAT_BE_OVERRUN BIT(29) +#define I2C_STAT_BE_ACCESS BIT(28) +#define I2C_STAT_LOST_ARB BIT(27) +#define I2C_STAT_NACK BIT(26) +#define I2C_STAT_DAT_REQ BIT(25) +#define I2C_STAT_CMD_COMP BIT(24) +#define I2C_STAT_STOP_ERR BIT(23) +#define I2C_STAT_MAX_PORT GENMASK(22, 16) +#define I2C_STAT_ANY_INT BIT(15) +#define I2C_STAT_SCL_IN BIT(11) +#define I2C_STAT_SDA_IN BIT(10) +#define I2C_STAT_PORT_BUSY BIT(9) +#define I2C_STAT_SELF_BUSY BIT(8) +#define I2C_STAT_FIFO_COUNT GENMASK(7, 0) + +#define I2C_STAT_ERR (I2C_STAT_INV_CMD | \ + I2C_STAT_PARITY | \ + I2C_STAT_BE_OVERRUN | \ + I2C_STAT_BE_ACCESS | \ + I2C_STAT_LOST_ARB | \ + I2C_STAT_NACK | \ + I2C_STAT_STOP_ERR) +#define I2C_STAT_ANY_RESP (I2C_STAT_ERR | \ + I2C_STAT_DAT_REQ | \ + I2C_STAT_CMD_COMP) + +/* extended status register */ +#define I2C_ESTAT_FIFO_SZ GENMASK(31, 24) +#define I2C_ESTAT_SCL_IN_SY BIT(15) +#define I2C_ESTAT_SDA_IN_SY BIT(14) +#define I2C_ESTAT_S_SCL BIT(13) +#define I2C_ESTAT_S_SDA BIT(12) +#define I2C_ESTAT_M_SCL BIT(11) +#define I2C_ESTAT_M_SDA BIT(10) +#define I2C_ESTAT_HI_WATER BIT(9) +#define I2C_ESTAT_LO_WATER BIT(8) +#define I2C_ESTAT_PORT_BUSY BIT(7) +#define I2C_ESTAT_SELF_BUSY BIT(6) +#define I2C_ESTAT_VERSION GENMASK(4, 0) + +/* port busy register */ +#define I2C_PORT_BUSY_RESET BIT(31) + +/* wait for command complete or data request */ +#define I2C_CMD_SLEEP_MAX_US 500 +#define I2C_CMD_SLEEP_MIN_US 50 + +/* wait after reset; choose time from legacy driver */ +#define I2C_RESET_SLEEP_MAX_US 2000 +#define I2C_RESET_SLEEP_MIN_US 1000 + +/* choose timeout length from legacy driver; it's well tested */ +#define I2C_ABORT_TIMEOUT msecs_to_jiffies(100) + +struct fsi_i2c_master { + struct fsi_device *fsi; + u8 fifo_size; + struct list_head ports; + struct mutex lock; +}; + +struct fsi_i2c_port { + struct list_head list; + struct i2c_adapter adapter; + struct fsi_i2c_master *master; + u16 port; + u16 xfrd; +}; + +static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + int rc; + __be32 data_be; + + rc = fsi_device_read(fsi, reg, &data_be, sizeof(data_be)); + if (rc) + return rc; + + *data = be32_to_cpu(data_be); + + return 0; +} + +static int fsi_i2c_write_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + __be32 data_be = cpu_to_be32p(data); + + return fsi_device_write(fsi, reg, &data_be, sizeof(data_be)); +} + +static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c) +{ + int rc; + u32 mode = I2C_MODE_ENHANCED, extended_status, watermark; + u32 interrupt = 0; + + /* since we use polling, disable interrupts */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_INT_MASK, &interrupt); + if (rc) + return rc; + + mode |= FIELD_PREP(I2C_MODE_CLKDIV, I2C_DEFAULT_CLK_DIV); + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_ESTAT, &extended_status); + if (rc) + return rc; + + i2c->fifo_size = FIELD_GET(I2C_ESTAT_FIFO_SZ, extended_status); + watermark = FIELD_PREP(I2C_WATERMARK_HI, + i2c->fifo_size - I2C_FIFO_HI_LVL); + watermark |= FIELD_PREP(I2C_WATERMARK_LO, I2C_FIFO_LO_LVL); + + return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark); +} + +static int fsi_i2c_set_port(struct fsi_i2c_port *port) +{ + int rc; + struct fsi_device *fsi = port->master->fsi; + u32 mode, dummy = 0; + + rc = fsi_i2c_read_reg(fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + if (FIELD_GET(I2C_MODE_PORT, mode) == port->port) + return 0; + + mode = (mode & ~I2C_MODE_PORT) | FIELD_PREP(I2C_MODE_PORT, port->port); + rc = fsi_i2c_write_reg(fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + /* reset engine when port is changed */ + return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy); +} + +static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg, + bool stop) +{ + struct fsi_i2c_master *i2c = port->master; + u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR; + + port->xfrd = 0; + + if (msg->flags & I2C_M_RD) + cmd |= I2C_CMD_READ; + + if (stop || msg->flags & I2C_M_STOP) + cmd |= I2C_CMD_WITH_STOP; + + cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr); + cmd |= FIELD_PREP(I2C_CMD_LEN, msg->len); + + return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_CMD, &cmd); +} + +static int fsi_i2c_get_op_bytes(int op_bytes) +{ + /* fsi is limited to max 4 byte aligned ops */ + if (op_bytes > 4) + return 4; + else if (op_bytes == 3) + return 2; + return op_bytes; +} + +static int fsi_i2c_write_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int write; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_write = i2c->fifo_size - fifo_count; + int bytes_remaining = msg->len - port->xfrd; + + bytes_to_write = min(bytes_to_write, bytes_remaining); + + while (bytes_to_write) { + write = fsi_i2c_get_op_bytes(bytes_to_write); + + rc = fsi_device_write(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], write); + if (rc) + return rc; + + port->xfrd += write; + bytes_to_write -= write; + } + + return 0; +} + +static int fsi_i2c_read_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int read; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_read; + int xfr_remaining = msg->len - port->xfrd; + u32 dummy; + + bytes_to_read = min_t(int, fifo_count, xfr_remaining); + + while (bytes_to_read) { + read = fsi_i2c_get_op_bytes(bytes_to_read); + + if (xfr_remaining) { + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], read); + if (rc) + return rc; + + port->xfrd += read; + xfr_remaining -= read; + } else { + /* no more buffer but data in fifo, need to clear it */ + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, &dummy, + read); + if (rc) + return rc; + } + + bytes_to_read -= read; + } + + return 0; +} + +static int fsi_i2c_get_scl(struct i2c_adapter *adap) +{ + u32 stat = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + + return !!(stat & I2C_STAT_SCL_IN); +} + +static void fsi_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + u32 dummy = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + if (val) + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SCL, &dummy); + else + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SCL, &dummy); +} + +static int fsi_i2c_get_sda(struct i2c_adapter *adap) +{ + u32 stat = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + + return !!(stat & I2C_STAT_SDA_IN); +} + +static void fsi_i2c_set_sda(struct i2c_adapter *adap, int val) +{ + u32 dummy = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + if (val) + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SDA, &dummy); + else + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SDA, &dummy); +} + +static void fsi_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + int rc; + u32 mode; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return; + + mode |= I2C_MODE_DIAG; + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); +} + +static void fsi_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + int rc; + u32 mode; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return; + + mode &= ~I2C_MODE_DIAG; + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); +} + +static int fsi_i2c_reset_bus(struct fsi_i2c_master *i2c, + struct fsi_i2c_port *port) +{ + int rc; + u32 stat, dummy = 0; + + /* force bus reset, ignore errors */ + i2c_recover_bus(&port->adapter); + + /* reset errors */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_ERR, &dummy); + if (rc) + return rc; + + /* wait for command complete */ + usleep_range(I2C_RESET_SLEEP_MIN_US, I2C_RESET_SLEEP_MAX_US); + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + if (stat & I2C_STAT_CMD_COMP) + return 0; + + /* failed to get command complete; reset engine again */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); + if (rc) + return rc; + + /* re-init engine again */ + return fsi_i2c_dev_init(i2c); +} + +static int fsi_i2c_reset_engine(struct fsi_i2c_master *i2c, u16 port) +{ + int rc; + u32 mode, dummy = 0; + + /* reset engine */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); + if (rc) + return rc; + + /* re-init engine */ + rc = fsi_i2c_dev_init(i2c); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + /* set port; default after reset is 0 */ + if (port) { + mode &= ~I2C_MODE_PORT; + mode |= FIELD_PREP(I2C_MODE_PORT, port); + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + } + + /* reset busy register; hw workaround */ + dummy = I2C_PORT_BUSY_RESET; + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_PORT_BUSY, &dummy); + if (rc) + return rc; + + return 0; +} + +static int fsi_i2c_abort(struct fsi_i2c_port *port, u32 status) +{ + int rc; + unsigned long start; + u32 cmd = I2C_CMD_WITH_STOP; + u32 stat; + struct fsi_i2c_master *i2c = port->master; + struct fsi_device *fsi = i2c->fsi; + + rc = fsi_i2c_reset_engine(i2c, port->port); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + /* if sda is low, peform full bus reset */ + if (!(stat & I2C_STAT_SDA_IN)) { + rc = fsi_i2c_reset_bus(i2c, port); + if (rc) + return rc; + } + + /* skip final stop command for these errors */ + if (status & (I2C_STAT_PARITY | I2C_STAT_LOST_ARB | I2C_STAT_STOP_ERR)) + return 0; + + /* write stop command */ + rc = fsi_i2c_write_reg(fsi, I2C_FSI_CMD, &cmd); + if (rc) + return rc; + + /* wait until we see command complete in the master */ + start = jiffies; + + do { + rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &status); + if (rc) + return rc; + + if (status & I2C_STAT_CMD_COMP) + return 0; + + usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); + } while (time_after(start + I2C_ABORT_TIMEOUT, jiffies)); + + return -ETIMEDOUT; +} + +static int fsi_i2c_handle_status(struct fsi_i2c_port *port, + struct i2c_msg *msg, u32 status) +{ + int rc; + u8 fifo_count; + + if (status & I2C_STAT_ERR) { + rc = fsi_i2c_abort(port, status); + if (rc) + return rc; + + if (status & I2C_STAT_INV_CMD) + return -EINVAL; + + if (status & (I2C_STAT_PARITY | I2C_STAT_BE_OVERRUN | + I2C_STAT_BE_ACCESS)) + return -EPROTO; + + if (status & I2C_STAT_NACK) + return -ENXIO; + + if (status & I2C_STAT_LOST_ARB) + return -EAGAIN; + + if (status & I2C_STAT_STOP_ERR) + return -EBADMSG; + + return -EIO; + } + + if (status & I2C_STAT_DAT_REQ) { + fifo_count = FIELD_GET(I2C_STAT_FIFO_COUNT, status); + + if (msg->flags & I2C_M_RD) + return fsi_i2c_read_fifo(port, msg, fifo_count); + + return fsi_i2c_write_fifo(port, msg, fifo_count); + } + + if (status & I2C_STAT_CMD_COMP) { + if (port->xfrd < msg->len) + return -ENODATA; + + return msg->len; + } + + return 0; +} + +static int fsi_i2c_wait(struct fsi_i2c_port *port, struct i2c_msg *msg, + unsigned long timeout) +{ + u32 status = 0; + int rc; + unsigned long start = jiffies; + + do { + rc = fsi_i2c_read_reg(port->master->fsi, I2C_FSI_STAT, + &status); + if (rc) + return rc; + + if (status & I2C_STAT_ANY_RESP) { + rc = fsi_i2c_handle_status(port, msg, status); + if (rc < 0) + return rc; + + /* cmd complete and all data xfrd */ + if (rc == msg->len) + return 0; + + /* need to xfr more data, but maybe don't need wait */ + continue; + } + + usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); + } while (time_after(start + timeout, jiffies)); + + return -ETIMEDOUT; +} + +static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + int i, rc; + unsigned long start_time; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *master = port->master; + struct i2c_msg *msg; + + mutex_lock(&master->lock); + + rc = fsi_i2c_set_port(port); + if (rc) + goto unlock; + + for (i = 0; i < num; i++) { + msg = msgs + i; + start_time = jiffies; + + rc = fsi_i2c_start(port, msg, i == num - 1); + if (rc) + goto unlock; + + rc = fsi_i2c_wait(port, msg, + adap->timeout - (jiffies - start_time)); + if (rc) + goto unlock; + } + +unlock: + mutex_unlock(&master->lock); + return rc ? : num; +} + +static u32 fsi_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | + I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static struct i2c_bus_recovery_info fsi_i2c_bus_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = fsi_i2c_get_scl, + .set_scl = fsi_i2c_set_scl, + .get_sda = fsi_i2c_get_sda, + .set_sda = fsi_i2c_set_sda, + .prepare_recovery = fsi_i2c_prepare_recovery, + .unprepare_recovery = fsi_i2c_unprepare_recovery, +}; + +static const struct i2c_algorithm fsi_i2c_algorithm = { + .master_xfer = fsi_i2c_xfer, + .functionality = fsi_i2c_functionality, +}; + +static struct device_node *fsi_i2c_find_port_of_node(struct device_node *fsi, + int port) +{ + struct device_node *np; + u32 port_no; + int rc; + + for_each_child_of_node(fsi, np) { + rc = of_property_read_u32(np, "reg", &port_no); + if (!rc && port_no == port) + return np; + } + + return NULL; +} + +static int fsi_i2c_probe(struct device *dev) +{ + struct fsi_i2c_master *i2c; + struct fsi_i2c_port *port; + struct device_node *np; + u32 port_no, ports, stat; + int rc; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + mutex_init(&i2c->lock); + i2c->fsi = to_fsi_dev(dev); + INIT_LIST_HEAD(&i2c->ports); + + rc = fsi_i2c_dev_init(i2c); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + ports = FIELD_GET(I2C_STAT_MAX_PORT, stat) + 1; + dev_dbg(dev, "I2C master has %d ports\n", ports); + + for (port_no = 0; port_no < ports; port_no++) { + np = fsi_i2c_find_port_of_node(dev->of_node, port_no); + if (!of_device_is_available(np)) + continue; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) { + of_node_put(np); + break; + } + + port->master = i2c; + port->port = port_no; + + port->adapter.owner = THIS_MODULE; + port->adapter.dev.of_node = np; + port->adapter.dev.parent = dev; + port->adapter.algo = &fsi_i2c_algorithm; + port->adapter.bus_recovery_info = &fsi_i2c_bus_recovery_info; + port->adapter.algo_data = port; + + snprintf(port->adapter.name, sizeof(port->adapter.name), + "i2c_bus-%u", port_no); + + rc = i2c_add_adapter(&port->adapter); + if (rc < 0) { + dev_err(dev, "Failed to register adapter: %d\n", rc); + kfree(port); + continue; + } + + list_add(&port->list, &i2c->ports); + } + + dev_set_drvdata(dev, i2c); + + return 0; +} + +static int fsi_i2c_remove(struct device *dev) +{ + struct fsi_i2c_master *i2c = dev_get_drvdata(dev); + struct fsi_i2c_port *port, *tmp; + + list_for_each_entry_safe(port, tmp, &i2c->ports, list) { + list_del(&port->list); + i2c_del_adapter(&port->adapter); + kfree(port); + } + + return 0; +} + +static const struct fsi_device_id fsi_i2c_ids[] = { + { FSI_ENGID_I2C, FSI_VERSION_ANY }, + { } +}; + +static struct fsi_driver fsi_i2c_driver = { + .id_table = fsi_i2c_ids, + .drv = { + .name = "i2c-fsi", + .bus = &fsi_bus_type, + .probe = fsi_i2c_probe, + .remove = fsi_i2c_remove, + }, +}; + +module_fsi_driver(fsi_i2c_driver); + +MODULE_AUTHOR("Eddie James "); +MODULE_DESCRIPTION("FSI attached I2C master"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3