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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/busses/i2c-designware-common.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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-common.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-common.c632
1 files changed, 632 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
new file mode 100644
index 000000000..581e02cc9
--- /dev/null
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -0,0 +1,632 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Synopsys DesignWare I2C adapter driver.
+ *
+ * Based on the TI DAVINCI I2C adapter driver.
+ *
+ * Copyright (C) 2006 Texas Instruments.
+ * Copyright (C) 2007 MontaVista Software Inc.
+ * Copyright (C) 2009 Provigent Ltd.
+ */
+#include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/swab.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include "i2c-designware-core.h"
+
+static char *abort_sources[] = {
+ [ABRT_7B_ADDR_NOACK] =
+ "slave address not acknowledged (7bit mode)",
+ [ABRT_10ADDR1_NOACK] =
+ "first address byte not acknowledged (10bit mode)",
+ [ABRT_10ADDR2_NOACK] =
+ "second address byte not acknowledged (10bit mode)",
+ [ABRT_TXDATA_NOACK] =
+ "data not acknowledged",
+ [ABRT_GCALL_NOACK] =
+ "no acknowledgement for a general call",
+ [ABRT_GCALL_READ] =
+ "read after general call",
+ [ABRT_SBYTE_ACKDET] =
+ "start byte acknowledged",
+ [ABRT_SBYTE_NORSTRT] =
+ "trying to send start byte when restart is disabled",
+ [ABRT_10B_RD_NORSTRT] =
+ "trying to read when restart is disabled (10bit mode)",
+ [ABRT_MASTER_DIS] =
+ "trying to use disabled adapter",
+ [ARB_LOST] =
+ "lost arbitration",
+ [ABRT_SLAVE_FLUSH_TXFIFO] =
+ "read command so flush old data in the TX FIFO",
+ [ABRT_SLAVE_ARBLOST] =
+ "slave lost the bus while transmitting data to a remote master",
+ [ABRT_SLAVE_RD_INTX] =
+ "incorrect slave-transmitter mode configuration",
+};
+
+static int dw_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ *val = readl_relaxed(dev->base + reg);
+
+ return 0;
+}
+
+static int dw_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ writel_relaxed(val, dev->base + reg);
+
+ return 0;
+}
+
+static int dw_reg_read_swab(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ *val = swab32(readl_relaxed(dev->base + reg));
+
+ return 0;
+}
+
+static int dw_reg_write_swab(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ writel_relaxed(swab32(val), dev->base + reg);
+
+ return 0;
+}
+
+static int dw_reg_read_word(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ *val = readw_relaxed(dev->base + reg) |
+ (readw_relaxed(dev->base + reg + 2) << 16);
+
+ return 0;
+}
+
+static int dw_reg_write_word(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ writew_relaxed(val, dev->base + reg);
+ writew_relaxed(val >> 16, dev->base + reg + 2);
+
+ return 0;
+}
+
+/**
+ * i2c_dw_init_regmap() - Initialize registers map
+ * @dev: device private data
+ *
+ * Autodetects needed register access mode and creates the regmap with
+ * corresponding read/write callbacks. This must be called before doing any
+ * other register access.
+ */
+int i2c_dw_init_regmap(struct dw_i2c_dev *dev)
+{
+ struct regmap_config map_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .disable_locking = true,
+ .reg_read = dw_reg_read,
+ .reg_write = dw_reg_write,
+ .max_register = DW_IC_COMP_TYPE,
+ };
+ u32 reg;
+ int ret;
+
+ /*
+ * Skip detecting the registers map configuration if the regmap has
+ * already been provided by a higher code.
+ */
+ if (dev->map)
+ return 0;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ reg = readl(dev->base + DW_IC_COMP_TYPE);
+ i2c_dw_release_lock(dev);
+
+ if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU)
+ map_cfg.max_register = AMD_UCSI_INTR_REG;
+
+ if (reg == swab32(DW_IC_COMP_TYPE_VALUE)) {
+ map_cfg.reg_read = dw_reg_read_swab;
+ map_cfg.reg_write = dw_reg_write_swab;
+ } else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) {
+ map_cfg.reg_read = dw_reg_read_word;
+ map_cfg.reg_write = dw_reg_write_word;
+ } else if (reg != DW_IC_COMP_TYPE_VALUE) {
+ dev_err(dev->dev,
+ "Unknown Synopsys component type: 0x%08x\n", reg);
+ return -ENODEV;
+ }
+
+ /*
+ * Note we'll check the return value of the regmap IO accessors only
+ * at the probe stage. The rest of the code won't do this because
+ * basically we have MMIO-based regmap so non of the read/write methods
+ * can fail.
+ */
+ dev->map = devm_regmap_init(dev->dev, NULL, dev, &map_cfg);
+ if (IS_ERR(dev->map)) {
+ dev_err(dev->dev, "Failed to init the registers map\n");
+ return PTR_ERR(dev->map);
+ }
+
+ return 0;
+}
+
+static const u32 supported_speeds[] = {
+ I2C_MAX_HIGH_SPEED_MODE_FREQ,
+ I2C_MAX_FAST_MODE_PLUS_FREQ,
+ I2C_MAX_FAST_MODE_FREQ,
+ I2C_MAX_STANDARD_MODE_FREQ,
+};
+
+int i2c_dw_validate_speed(struct dw_i2c_dev *dev)
+{
+ struct i2c_timings *t = &dev->timings;
+ unsigned int i;
+
+ /*
+ * Only standard mode at 100kHz, fast mode at 400kHz,
+ * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
+ */
+ for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
+ if (t->bus_freq_hz == supported_speeds[i])
+ return 0;
+ }
+
+ dev_err(dev->dev,
+ "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
+ t->bus_freq_hz);
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_validate_speed);
+
+#ifdef CONFIG_ACPI
+
+#include <linux/dmi.h>
+
+/*
+ * The HCNT/LCNT information coming from ACPI should be the most accurate
+ * for given platform. However, some systems get it wrong. On such systems
+ * we get better results by calculating those based on the input clock.
+ */
+static const struct dmi_system_id i2c_dw_no_acpi_params[] = {
+ {
+ .ident = "Dell Inspiron 7348",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
+ },
+ },
+ {}
+};
+
+static void i2c_dw_acpi_params(struct device *device, char method[],
+ u16 *hcnt, u16 *lcnt, u32 *sda_hold)
+{
+ struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+ acpi_handle handle = ACPI_HANDLE(device);
+ union acpi_object *obj;
+
+ if (dmi_check_system(i2c_dw_no_acpi_params))
+ return;
+
+ if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
+ return;
+
+ obj = (union acpi_object *)buf.pointer;
+ if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
+ const union acpi_object *objs = obj->package.elements;
+
+ *hcnt = (u16)objs[0].integer.value;
+ *lcnt = (u16)objs[1].integer.value;
+ *sda_hold = (u32)objs[2].integer.value;
+ }
+
+ kfree(buf.pointer);
+}
+
+int i2c_dw_acpi_configure(struct device *device)
+{
+ struct dw_i2c_dev *dev = dev_get_drvdata(device);
+ struct i2c_timings *t = &dev->timings;
+ u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
+
+ /*
+ * Try to get SDA hold time and *CNT values from an ACPI method for
+ * selected speed modes.
+ */
+ i2c_dw_acpi_params(device, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
+ i2c_dw_acpi_params(device, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
+ i2c_dw_acpi_params(device, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
+ i2c_dw_acpi_params(device, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
+
+ switch (t->bus_freq_hz) {
+ case I2C_MAX_STANDARD_MODE_FREQ:
+ dev->sda_hold_time = ss_ht;
+ break;
+ case I2C_MAX_FAST_MODE_PLUS_FREQ:
+ dev->sda_hold_time = fp_ht;
+ break;
+ case I2C_MAX_HIGH_SPEED_MODE_FREQ:
+ dev->sda_hold_time = hs_ht;
+ break;
+ case I2C_MAX_FAST_MODE_FREQ:
+ default:
+ dev->sda_hold_time = fs_ht;
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_acpi_configure);
+
+static u32 i2c_dw_acpi_round_bus_speed(struct device *device)
+{
+ u32 acpi_speed;
+ int i;
+
+ acpi_speed = i2c_acpi_find_bus_speed(device);
+ /*
+ * Some DSTDs use a non standard speed, round down to the lowest
+ * standard speed.
+ */
+ for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
+ if (acpi_speed >= supported_speeds[i])
+ return supported_speeds[i];
+ }
+
+ return 0;
+}
+
+#else /* CONFIG_ACPI */
+
+static inline u32 i2c_dw_acpi_round_bus_speed(struct device *device) { return 0; }
+
+#endif /* CONFIG_ACPI */
+
+void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev)
+{
+ u32 acpi_speed = i2c_dw_acpi_round_bus_speed(dev->dev);
+ struct i2c_timings *t = &dev->timings;
+
+ /*
+ * Find bus speed from the "clock-frequency" device property, ACPI
+ * or by using fast mode if neither is set.
+ */
+ if (acpi_speed && t->bus_freq_hz)
+ t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
+ else if (acpi_speed || t->bus_freq_hz)
+ t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
+ else
+ t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_adjust_bus_speed);
+
+u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
+{
+ /*
+ * DesignWare I2C core doesn't seem to have solid strategy to meet
+ * the tHD;STA timing spec. Configuring _HCNT based on tHIGH spec
+ * will result in violation of the tHD;STA spec.
+ */
+ if (cond)
+ /*
+ * Conditional expression:
+ *
+ * IC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH
+ *
+ * This is based on the DW manuals, and represents an ideal
+ * configuration. The resulting I2C bus speed will be
+ * faster than any of the others.
+ *
+ * If your hardware is free from tHD;STA issue, try this one.
+ */
+ return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * tSYMBOL, MICRO) -
+ 8 + offset;
+ else
+ /*
+ * Conditional expression:
+ *
+ * IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf)
+ *
+ * This is just experimental rule; the tHD;STA period turned
+ * out to be proportinal to (_HCNT + 3). With this setting,
+ * we could meet both tHIGH and tHD;STA timing specs.
+ *
+ * If unsure, you'd better to take this alternative.
+ *
+ * The reason why we need to take into account "tf" here,
+ * is the same as described in i2c_dw_scl_lcnt().
+ */
+ return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), MICRO) -
+ 3 + offset;
+}
+
+u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
+{
+ /*
+ * Conditional expression:
+ *
+ * IC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf)
+ *
+ * DW I2C core starts counting the SCL CNTs for the LOW period
+ * of the SCL clock (tLOW) as soon as it pulls the SCL line.
+ * In order to meet the tLOW timing spec, we need to take into
+ * account the fall time of SCL signal (tf). Default tf value
+ * should be 0.3 us, for safety.
+ */
+ return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) -
+ 1 + offset;
+}
+
+int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
+{
+ u32 reg;
+ int ret;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ /* Configure SDA Hold Time if required */
+ ret = regmap_read(dev->map, DW_IC_COMP_VERSION, &reg);
+ if (ret)
+ goto err_release_lock;
+
+ if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {
+ if (!dev->sda_hold_time) {
+ /* Keep previous hold time setting if no one set it */
+ ret = regmap_read(dev->map, DW_IC_SDA_HOLD,
+ &dev->sda_hold_time);
+ if (ret)
+ goto err_release_lock;
+ }
+
+ /*
+ * Workaround for avoiding TX arbitration lost in case I2C
+ * slave pulls SDA down "too quickly" after falling edge of
+ * SCL by enabling non-zero SDA RX hold. Specification says it
+ * extends incoming SDA low to high transition while SCL is
+ * high but it appears to help also above issue.
+ */
+ if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
+ dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+
+ dev_dbg(dev->dev, "SDA Hold Time TX:RX = %d:%d\n",
+ dev->sda_hold_time & ~(u32)DW_IC_SDA_HOLD_RX_MASK,
+ dev->sda_hold_time >> DW_IC_SDA_HOLD_RX_SHIFT);
+ } else if (dev->set_sda_hold_time) {
+ dev->set_sda_hold_time(dev);
+ } else if (dev->sda_hold_time) {
+ dev_warn(dev->dev,
+ "Hardware too old to adjust SDA hold time.\n");
+ dev->sda_hold_time = 0;
+ }
+
+err_release_lock:
+ i2c_dw_release_lock(dev);
+
+ return ret;
+}
+
+void __i2c_dw_disable(struct dw_i2c_dev *dev)
+{
+ int timeout = 100;
+ u32 status;
+
+ do {
+ __i2c_dw_disable_nowait(dev);
+ /*
+ * The enable status register may be unimplemented, but
+ * in that case this test reads zero and exits the loop.
+ */
+ regmap_read(dev->map, DW_IC_ENABLE_STATUS, &status);
+ if ((status & 1) == 0)
+ return;
+
+ /*
+ * Wait 10 times the signaling period of the highest I2C
+ * transfer supported by the driver (for 400KHz this is
+ * 25us) as described in the DesignWare I2C databook.
+ */
+ usleep_range(25, 250);
+ } while (timeout--);
+
+ dev_warn(dev->dev, "timeout in disabling adapter\n");
+}
+
+unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
+{
+ /*
+ * Clock is not necessary if we got LCNT/HCNT values directly from
+ * the platform code.
+ */
+ if (WARN_ON_ONCE(!dev->get_clk_rate_khz))
+ return 0;
+ return dev->get_clk_rate_khz(dev);
+}
+
+int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare)
+{
+ int ret;
+
+ if (prepare) {
+ /* Optional interface clock */
+ ret = clk_prepare_enable(dev->pclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(dev->clk);
+ if (ret)
+ clk_disable_unprepare(dev->pclk);
+
+ return ret;
+ }
+
+ clk_disable_unprepare(dev->clk);
+ clk_disable_unprepare(dev->pclk);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_prepare_clk);
+
+int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
+{
+ int ret;
+
+ if (!dev->acquire_lock)
+ return 0;
+
+ ret = dev->acquire_lock();
+ if (!ret)
+ return 0;
+
+ dev_err(dev->dev, "couldn't acquire bus ownership\n");
+
+ return ret;
+}
+
+void i2c_dw_release_lock(struct dw_i2c_dev *dev)
+{
+ if (dev->release_lock)
+ dev->release_lock();
+}
+
+/*
+ * Waiting for bus not busy
+ */
+int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
+{
+ u32 status;
+ int ret;
+
+ ret = regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
+ !(status & DW_IC_STATUS_ACTIVITY),
+ 1100, 20000);
+ if (ret) {
+ dev_warn(dev->dev, "timeout waiting for bus ready\n");
+
+ i2c_recover_bus(&dev->adapter);
+
+ regmap_read(dev->map, DW_IC_STATUS, &status);
+ if (!(status & DW_IC_STATUS_ACTIVITY))
+ ret = 0;
+ }
+
+ return ret;
+}
+
+int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
+{
+ unsigned long abort_source = dev->abort_source;
+ int i;
+
+ if (abort_source & DW_IC_TX_ABRT_NOACK) {
+ for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources))
+ dev_dbg(dev->dev,
+ "%s: %s\n", __func__, abort_sources[i]);
+ return -EREMOTEIO;
+ }
+
+ for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources))
+ dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]);
+
+ if (abort_source & DW_IC_TX_ARB_LOST)
+ return -EAGAIN;
+ else if (abort_source & DW_IC_TX_ABRT_GCALL_READ)
+ return -EINVAL; /* wrong msgs[] data */
+ else
+ return -EIO;
+}
+
+int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev)
+{
+ u32 param, tx_fifo_depth, rx_fifo_depth;
+ int ret;
+
+ /*
+ * Try to detect the FIFO depth if not set by interface driver,
+ * the depth could be from 2 to 256 from HW spec.
+ */
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &param);
+ i2c_dw_release_lock(dev);
+ if (ret)
+ return ret;
+
+ tx_fifo_depth = ((param >> 16) & 0xff) + 1;
+ rx_fifo_depth = ((param >> 8) & 0xff) + 1;
+ if (!dev->tx_fifo_depth) {
+ dev->tx_fifo_depth = tx_fifo_depth;
+ dev->rx_fifo_depth = rx_fifo_depth;
+ } else if (tx_fifo_depth >= 2) {
+ dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
+ tx_fifo_depth);
+ dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
+ rx_fifo_depth);
+ }
+
+ return 0;
+}
+
+u32 i2c_dw_func(struct i2c_adapter *adap)
+{
+ struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ return dev->functionality;
+}
+
+void i2c_dw_disable(struct dw_i2c_dev *dev)
+{
+ u32 dummy;
+ int ret;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return;
+
+ /* Disable controller */
+ __i2c_dw_disable(dev);
+
+ /* Disable all interrupts */
+ regmap_write(dev->map, DW_IC_INTR_MASK, 0);
+ regmap_read(dev->map, DW_IC_CLR_INTR, &dummy);
+
+ i2c_dw_release_lock(dev);
+}
+
+MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
+MODULE_LICENSE("GPL");