aboutsummaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-designware-slave.c
diff options
context:
space:
mode:
authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/i2c/busses/i2c-designware-slave.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/busses/i2c-designware-slave.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-slave.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c
new file mode 100644
index 000000000..c6d2e4c2a
--- /dev/null
+++ b/drivers/i2c/busses/i2c-designware-slave.c
@@ -0,0 +1,277 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Synopsys DesignWare I2C adapter driver (slave only).
+ *
+ * Based on the Synopsys DesignWare I2C adapter driver (master).
+ *
+ * Copyright (C) 2016 Synopsys Inc.
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+
+#include "i2c-designware-core.h"
+
+static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev)
+{
+ /* Configure Tx/Rx FIFO threshold levels. */
+ regmap_write(dev->map, DW_IC_TX_TL, 0);
+ regmap_write(dev->map, DW_IC_RX_TL, 0);
+
+ /* Configure the I2C slave. */
+ regmap_write(dev->map, DW_IC_CON, dev->slave_cfg);
+ regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_SLAVE_MASK);
+}
+
+/**
+ * i2c_dw_init_slave() - Initialize the designware i2c slave hardware
+ * @dev: device private data
+ *
+ * This function configures and enables the I2C in slave mode.
+ * This function is called during I2C init function, and in case of timeout at
+ * run time.
+ */
+static int i2c_dw_init_slave(struct dw_i2c_dev *dev)
+{
+ int ret;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ /* Disable the adapter. */
+ __i2c_dw_disable(dev);
+
+ /* Write SDA hold time if supported */
+ if (dev->sda_hold_time)
+ regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time);
+
+ i2c_dw_configure_fifo_slave(dev);
+ i2c_dw_release_lock(dev);
+
+ return 0;
+}
+
+static int i2c_dw_reg_slave(struct i2c_client *slave)
+{
+ struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter);
+
+ if (dev->slave)
+ return -EBUSY;
+ if (slave->flags & I2C_CLIENT_TEN)
+ return -EAFNOSUPPORT;
+ pm_runtime_get_sync(dev->dev);
+
+ /*
+ * Set slave address in the IC_SAR register,
+ * the address to which the DW_apb_i2c responds.
+ */
+ __i2c_dw_disable_nowait(dev);
+ regmap_write(dev->map, DW_IC_SAR, slave->addr);
+ dev->slave = slave;
+
+ __i2c_dw_enable(dev);
+
+ dev->status = 0;
+
+ return 0;
+}
+
+static int i2c_dw_unreg_slave(struct i2c_client *slave)
+{
+ struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter);
+
+ regmap_write(dev->map, DW_IC_INTR_MASK, 0);
+ dev->disable(dev);
+ synchronize_irq(dev->irq);
+ dev->slave = NULL;
+ pm_runtime_put(dev->dev);
+
+ return 0;
+}
+
+static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev)
+{
+ u32 stat, dummy;
+
+ /*
+ * The IC_INTR_STAT register just indicates "enabled" interrupts.
+ * The unmasked raw version of interrupt status bits is available
+ * in the IC_RAW_INTR_STAT register.
+ *
+ * That is,
+ * stat = readl(IC_INTR_STAT);
+ * equals to,
+ * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK);
+ *
+ * The raw version might be useful for debugging purposes.
+ */
+ regmap_read(dev->map, DW_IC_INTR_STAT, &stat);
+
+ /*
+ * Do not use the IC_CLR_INTR register to clear interrupts, or
+ * you'll miss some interrupts, triggered during the period from
+ * readl(IC_INTR_STAT) to readl(IC_CLR_INTR).
+ *
+ * Instead, use the separately-prepared IC_CLR_* registers.
+ */
+ if (stat & DW_IC_INTR_TX_ABRT)
+ regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy);
+ if (stat & DW_IC_INTR_RX_UNDER)
+ regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy);
+ if (stat & DW_IC_INTR_RX_OVER)
+ regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy);
+ if (stat & DW_IC_INTR_TX_OVER)
+ regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy);
+ if (stat & DW_IC_INTR_RX_DONE)
+ regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy);
+ if (stat & DW_IC_INTR_ACTIVITY)
+ regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy);
+ if (stat & DW_IC_INTR_STOP_DET)
+ regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy);
+ if (stat & DW_IC_INTR_START_DET)
+ regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy);
+ if (stat & DW_IC_INTR_GEN_CALL)
+ regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy);
+
+ return stat;
+}
+
+/*
+ * Interrupt service routine. This gets called whenever an I2C slave interrupt
+ * occurs.
+ */
+static irqreturn_t i2c_dw_isr_slave(int this_irq, void *dev_id)
+{
+ struct dw_i2c_dev *dev = dev_id;
+ u32 raw_stat, stat, enabled, tmp;
+ u8 val = 0, slave_activity;
+
+ regmap_read(dev->map, DW_IC_ENABLE, &enabled);
+ regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat);
+ regmap_read(dev->map, DW_IC_STATUS, &tmp);
+ slave_activity = ((tmp & DW_IC_STATUS_SLAVE_ACTIVITY) >> 6);
+
+ if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave)
+ return IRQ_NONE;
+
+ stat = i2c_dw_read_clear_intrbits_slave(dev);
+ dev_dbg(dev->dev,
+ "%#x STATUS SLAVE_ACTIVITY=%#x : RAW_INTR_STAT=%#x : INTR_STAT=%#x\n",
+ enabled, slave_activity, raw_stat, stat);
+
+ if (stat & DW_IC_INTR_RX_FULL) {
+ if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) {
+ dev->status |= STATUS_WRITE_IN_PROGRESS;
+ dev->status &= ~STATUS_READ_IN_PROGRESS;
+ i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED,
+ &val);
+ }
+
+ do {
+ regmap_read(dev->map, DW_IC_DATA_CMD, &tmp);
+ val = tmp;
+ i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED,
+ &val);
+ regmap_read(dev->map, DW_IC_STATUS, &tmp);
+ } while (tmp & DW_IC_STATUS_RFNE);
+ }
+
+ if (stat & DW_IC_INTR_RD_REQ) {
+ if (slave_activity) {
+ regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);
+
+ if (!(dev->status & STATUS_READ_IN_PROGRESS)) {
+ i2c_slave_event(dev->slave,
+ I2C_SLAVE_READ_REQUESTED,
+ &val);
+ dev->status |= STATUS_READ_IN_PROGRESS;
+ dev->status &= ~STATUS_WRITE_IN_PROGRESS;
+ } else {
+ i2c_slave_event(dev->slave,
+ I2C_SLAVE_READ_PROCESSED,
+ &val);
+ }
+ regmap_write(dev->map, DW_IC_DATA_CMD, val);
+ }
+ }
+
+ if (stat & DW_IC_INTR_STOP_DET)
+ i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val);
+
+ return IRQ_HANDLED;
+}
+
+static const struct i2c_algorithm i2c_dw_algo = {
+ .functionality = i2c_dw_func,
+ .reg_slave = i2c_dw_reg_slave,
+ .unreg_slave = i2c_dw_unreg_slave,
+};
+
+void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
+{
+ dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
+
+ dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
+ DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
+
+ dev->mode = DW_IC_SLAVE;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_configure_slave);
+
+int i2c_dw_probe_slave(struct dw_i2c_dev *dev)
+{
+ struct i2c_adapter *adap = &dev->adapter;
+ int ret;
+
+ dev->init = i2c_dw_init_slave;
+ dev->disable = i2c_dw_disable;
+
+ ret = i2c_dw_init_regmap(dev);
+ if (ret)
+ return ret;
+
+ ret = i2c_dw_set_sda_hold(dev);
+ if (ret)
+ return ret;
+
+ ret = i2c_dw_set_fifo_size(dev);
+ if (ret)
+ return ret;
+
+ ret = dev->init(dev);
+ if (ret)
+ return ret;
+
+ snprintf(adap->name, sizeof(adap->name),
+ "Synopsys DesignWare I2C Slave adapter");
+ adap->retries = 3;
+ adap->algo = &i2c_dw_algo;
+ adap->dev.parent = dev->dev;
+ i2c_set_adapdata(adap, dev);
+
+ ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr_slave,
+ IRQF_SHARED, dev_name(dev->dev), dev);
+ if (ret) {
+ dev_err(dev->dev, "failure requesting irq %i: %d\n",
+ dev->irq, ret);
+ return ret;
+ }
+
+ ret = i2c_add_numbered_adapter(adap);
+ if (ret)
+ dev_err(dev->dev, "failure adding adapter: %d\n", ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_probe_slave);
+
+MODULE_AUTHOR("Luis Oliveira <lolivei@synopsys.com>");
+MODULE_DESCRIPTION("Synopsys DesignWare I2C bus slave adapter");
+MODULE_LICENSE("GPL v2");