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().
  ...

1 files changed, 883 insertions, 0 deletions

diff --git a/drivers/spi/spi-dln2.c b/drivers/spi/spi-dln2.c
new file mode 100644
index 000000000..0a1fb2bc9
--- /dev/null
+++ b/drivers/spi/spi-dln2.c
@@ -0,0 +1,883 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for the Diolan DLN-2 USB-SPI adapter
+ *
+ * Copyright (c) 2014 Intel Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/mfd/dln2.h>
+#include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
+#include <asm/unaligned.h>
+
+#define DLN2_SPI_MODULE_ID		0x02
+#define DLN2_SPI_CMD(cmd)		DLN2_CMD(cmd, DLN2_SPI_MODULE_ID)
+
+/* SPI commands */
+#define DLN2_SPI_GET_PORT_COUNT			DLN2_SPI_CMD(0x00)
+#define DLN2_SPI_ENABLE				DLN2_SPI_CMD(0x11)
+#define DLN2_SPI_DISABLE			DLN2_SPI_CMD(0x12)
+#define DLN2_SPI_IS_ENABLED			DLN2_SPI_CMD(0x13)
+#define DLN2_SPI_SET_MODE			DLN2_SPI_CMD(0x14)
+#define DLN2_SPI_GET_MODE			DLN2_SPI_CMD(0x15)
+#define DLN2_SPI_SET_FRAME_SIZE			DLN2_SPI_CMD(0x16)
+#define DLN2_SPI_GET_FRAME_SIZE			DLN2_SPI_CMD(0x17)
+#define DLN2_SPI_SET_FREQUENCY			DLN2_SPI_CMD(0x18)
+#define DLN2_SPI_GET_FREQUENCY			DLN2_SPI_CMD(0x19)
+#define DLN2_SPI_READ_WRITE			DLN2_SPI_CMD(0x1A)
+#define DLN2_SPI_READ				DLN2_SPI_CMD(0x1B)
+#define DLN2_SPI_WRITE				DLN2_SPI_CMD(0x1C)
+#define DLN2_SPI_SET_DELAY_BETWEEN_SS		DLN2_SPI_CMD(0x20)
+#define DLN2_SPI_GET_DELAY_BETWEEN_SS		DLN2_SPI_CMD(0x21)
+#define DLN2_SPI_SET_DELAY_AFTER_SS		DLN2_SPI_CMD(0x22)
+#define DLN2_SPI_GET_DELAY_AFTER_SS		DLN2_SPI_CMD(0x23)
+#define DLN2_SPI_SET_DELAY_BETWEEN_FRAMES	DLN2_SPI_CMD(0x24)
+#define DLN2_SPI_GET_DELAY_BETWEEN_FRAMES	DLN2_SPI_CMD(0x25)
+#define DLN2_SPI_SET_SS				DLN2_SPI_CMD(0x26)
+#define DLN2_SPI_GET_SS				DLN2_SPI_CMD(0x27)
+#define DLN2_SPI_RELEASE_SS			DLN2_SPI_CMD(0x28)
+#define DLN2_SPI_SS_VARIABLE_ENABLE		DLN2_SPI_CMD(0x2B)
+#define DLN2_SPI_SS_VARIABLE_DISABLE		DLN2_SPI_CMD(0x2C)
+#define DLN2_SPI_SS_VARIABLE_IS_ENABLED		DLN2_SPI_CMD(0x2D)
+#define DLN2_SPI_SS_AAT_ENABLE			DLN2_SPI_CMD(0x2E)
+#define DLN2_SPI_SS_AAT_DISABLE			DLN2_SPI_CMD(0x2F)
+#define DLN2_SPI_SS_AAT_IS_ENABLED		DLN2_SPI_CMD(0x30)
+#define DLN2_SPI_SS_BETWEEN_FRAMES_ENABLE	DLN2_SPI_CMD(0x31)
+#define DLN2_SPI_SS_BETWEEN_FRAMES_DISABLE	DLN2_SPI_CMD(0x32)
+#define DLN2_SPI_SS_BETWEEN_FRAMES_IS_ENABLED	DLN2_SPI_CMD(0x33)
+#define DLN2_SPI_SET_CPHA			DLN2_SPI_CMD(0x34)
+#define DLN2_SPI_GET_CPHA			DLN2_SPI_CMD(0x35)
+#define DLN2_SPI_SET_CPOL			DLN2_SPI_CMD(0x36)
+#define DLN2_SPI_GET_CPOL			DLN2_SPI_CMD(0x37)
+#define DLN2_SPI_SS_MULTI_ENABLE		DLN2_SPI_CMD(0x38)
+#define DLN2_SPI_SS_MULTI_DISABLE		DLN2_SPI_CMD(0x39)
+#define DLN2_SPI_SS_MULTI_IS_ENABLED		DLN2_SPI_CMD(0x3A)
+#define DLN2_SPI_GET_SUPPORTED_MODES		DLN2_SPI_CMD(0x40)
+#define DLN2_SPI_GET_SUPPORTED_CPHA_VALUES	DLN2_SPI_CMD(0x41)
+#define DLN2_SPI_GET_SUPPORTED_CPOL_VALUES	DLN2_SPI_CMD(0x42)
+#define DLN2_SPI_GET_SUPPORTED_FRAME_SIZES	DLN2_SPI_CMD(0x43)
+#define DLN2_SPI_GET_SS_COUNT			DLN2_SPI_CMD(0x44)
+#define DLN2_SPI_GET_MIN_FREQUENCY		DLN2_SPI_CMD(0x45)
+#define DLN2_SPI_GET_MAX_FREQUENCY		DLN2_SPI_CMD(0x46)
+#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_SS	DLN2_SPI_CMD(0x47)
+#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_SS	DLN2_SPI_CMD(0x48)
+#define DLN2_SPI_GET_MIN_DELAY_AFTER_SS		DLN2_SPI_CMD(0x49)
+#define DLN2_SPI_GET_MAX_DELAY_AFTER_SS		DLN2_SPI_CMD(0x4A)
+#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_FRAMES	DLN2_SPI_CMD(0x4B)
+#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_FRAMES	DLN2_SPI_CMD(0x4C)
+
+#define DLN2_SPI_MAX_XFER_SIZE			256
+#define DLN2_SPI_BUF_SIZE			(DLN2_SPI_MAX_XFER_SIZE + 16)
+#define DLN2_SPI_ATTR_LEAVE_SS_LOW		BIT(0)
+#define DLN2_TRANSFERS_WAIT_COMPLETE		1
+#define DLN2_TRANSFERS_CANCEL			0
+#define DLN2_RPM_AUTOSUSPEND_TIMEOUT		2000
+
+struct dln2_spi {
+	struct platform_device *pdev;
+	struct spi_master *master;
+	u8 port;
+
+	/*
+	 * This buffer will be used mainly for read/write operations. Since
+	 * they're quite large, we cannot use the stack. Protection is not
+	 * needed because all SPI communication is serialized by the SPI core.
+	 */
+	void *buf;
+
+	u8 bpw;
+	u32 speed;
+	u16 mode;
+	u8 cs;
+};
+
+/*
+ * Enable/Disable SPI module. The disable command will wait for transfers to
+ * complete first.
+ */
+static int dln2_spi_enable(struct dln2_spi *dln2, bool enable)
+{
+	u16 cmd;
+	struct {
+		u8 port;
+		u8 wait_for_completion;
+	} tx;
+	unsigned len = sizeof(tx);
+
+	tx.port = dln2->port;
+
+	if (enable) {
+		cmd = DLN2_SPI_ENABLE;
+		len -= sizeof(tx.wait_for_completion);
+	} else {
+		tx.wait_for_completion = DLN2_TRANSFERS_WAIT_COMPLETE;
+		cmd = DLN2_SPI_DISABLE;
+	}
+
+	return dln2_transfer_tx(dln2->pdev, cmd, &tx, len);
+}
+
+/*
+ * Select/unselect multiple CS lines. The selected lines will be automatically
+ * toggled LOW/HIGH by the board firmware during transfers, provided they're
+ * enabled first.
+ *
+ * Ex: cs_mask = 0x03 -> CS0 & CS1 will be selected and the next WR/RD operation
+ *                       will toggle the lines LOW/HIGH automatically.
+ */
+static int dln2_spi_cs_set(struct dln2_spi *dln2, u8 cs_mask)
+{
+	struct {
+		u8 port;
+		u8 cs;
+	} tx;
+
+	tx.port = dln2->port;
+
+	/*
+	 * According to Diolan docs, "a slave device can be selected by changing
+	 * the corresponding bit value to 0". The rest must be set to 1. Hence
+	 * the bitwise NOT in front.
+	 */
+	tx.cs = ~cs_mask;
+
+	return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_SS, &tx, sizeof(tx));
+}
+
+/*
+ * Select one CS line. The other lines will be un-selected.
+ */
+static int dln2_spi_cs_set_one(struct dln2_spi *dln2, u8 cs)
+{
+	return dln2_spi_cs_set(dln2, BIT(cs));
+}
+
+/*
+ * Enable/disable CS lines for usage. The module has to be disabled first.
+ */
+static int dln2_spi_cs_enable(struct dln2_spi *dln2, u8 cs_mask, bool enable)
+{
+	struct {
+		u8 port;
+		u8 cs;
+	} tx;
+	u16 cmd;
+
+	tx.port = dln2->port;
+	tx.cs = cs_mask;
+	cmd = enable ? DLN2_SPI_SS_MULTI_ENABLE : DLN2_SPI_SS_MULTI_DISABLE;
+
+	return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx));
+}
+
+static int dln2_spi_cs_enable_all(struct dln2_spi *dln2, bool enable)
+{
+	u8 cs_mask = GENMASK(dln2->master->num_chipselect - 1, 0);
+
+	return dln2_spi_cs_enable(dln2, cs_mask, enable);
+}
+
+static int dln2_spi_get_cs_num(struct dln2_spi *dln2, u16 *cs_num)
+{
+	int ret;
+	struct {
+		u8 port;
+	} tx;
+	struct {
+		__le16 cs_count;
+	} rx;
+	unsigned rx_len = sizeof(rx);
+
+	tx.port = dln2->port;
+	ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SS_COUNT, &tx, sizeof(tx),
+			    &rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(rx))
+		return -EPROTO;
+
+	*cs_num = le16_to_cpu(rx.cs_count);
+
+	dev_dbg(&dln2->pdev->dev, "cs_num = %d\n", *cs_num);
+
+	return 0;
+}
+
+static int dln2_spi_get_speed(struct dln2_spi *dln2, u16 cmd, u32 *freq)
+{
+	int ret;
+	struct {
+		u8 port;
+	} tx;
+	struct {
+		__le32 speed;
+	} rx;
+	unsigned rx_len = sizeof(rx);
+
+	tx.port = dln2->port;
+
+	ret = dln2_transfer(dln2->pdev, cmd, &tx, sizeof(tx), &rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(rx))
+		return -EPROTO;
+
+	*freq = le32_to_cpu(rx.speed);
+
+	return 0;
+}
+
+/*
+ * Get bus min/max frequencies.
+ */
+static int dln2_spi_get_speed_range(struct dln2_spi *dln2, u32 *fmin, u32 *fmax)
+{
+	int ret;
+
+	ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MIN_FREQUENCY, fmin);
+	if (ret < 0)
+		return ret;
+
+	ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MAX_FREQUENCY, fmax);
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(&dln2->pdev->dev, "freq_min = %d, freq_max = %d\n",
+		*fmin, *fmax);
+
+	return 0;
+}
+
+/*
+ * Set the bus speed. The module will automatically round down to the closest
+ * available frequency and returns it. The module has to be disabled first.
+ */
+static int dln2_spi_set_speed(struct dln2_spi *dln2, u32 speed)
+{
+	int ret;
+	struct {
+		u8 port;
+		__le32 speed;
+	} __packed tx;
+	struct {
+		__le32 speed;
+	} rx;
+	int rx_len = sizeof(rx);
+
+	tx.port = dln2->port;
+	tx.speed = cpu_to_le32(speed);
+
+	ret = dln2_transfer(dln2->pdev, DLN2_SPI_SET_FREQUENCY, &tx, sizeof(tx),
+			    &rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(rx))
+		return -EPROTO;
+
+	return 0;
+}
+
+/*
+ * Change CPOL & CPHA. The module has to be disabled first.
+ */
+static int dln2_spi_set_mode(struct dln2_spi *dln2, u8 mode)
+{
+	struct {
+		u8 port;
+		u8 mode;
+	} tx;
+
+	tx.port = dln2->port;
+	tx.mode = mode;
+
+	return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_MODE, &tx, sizeof(tx));
+}
+
+/*
+ * Change frame size. The module has to be disabled first.
+ */
+static int dln2_spi_set_bpw(struct dln2_spi *dln2, u8 bpw)
+{
+	struct {
+		u8 port;
+		u8 bpw;
+	} tx;
+
+	tx.port = dln2->port;
+	tx.bpw = bpw;
+
+	return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_FRAME_SIZE,
+				&tx, sizeof(tx));
+}
+
+static int dln2_spi_get_supported_frame_sizes(struct dln2_spi *dln2,
+					      u32 *bpw_mask)
+{
+	int ret;
+	struct {
+		u8 port;
+	} tx;
+	struct {
+		u8 count;
+		u8 frame_sizes[36];
+	} *rx = dln2->buf;
+	unsigned rx_len = sizeof(*rx);
+	int i;
+
+	tx.port = dln2->port;
+
+	ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SUPPORTED_FRAME_SIZES,
+			    &tx, sizeof(tx), rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(*rx))
+		return -EPROTO;
+	if (rx->count > ARRAY_SIZE(rx->frame_sizes))
+		return -EPROTO;
+
+	*bpw_mask = 0;
+	for (i = 0; i < rx->count; i++)
+		*bpw_mask |= BIT(rx->frame_sizes[i] - 1);
+
+	dev_dbg(&dln2->pdev->dev, "bpw_mask = 0x%X\n", *bpw_mask);
+
+	return 0;
+}
+
+/*
+ * Copy the data to DLN2 buffer and change the byte order to LE, requested by
+ * DLN2 module. SPI core makes sure that the data length is a multiple of word
+ * size.
+ */
+static int dln2_spi_copy_to_buf(u8 *dln2_buf, const u8 *src, u16 len, u8 bpw)
+{
+#ifdef __LITTLE_ENDIAN
+	memcpy(dln2_buf, src, len);
+#else
+	if (bpw <= 8) {
+		memcpy(dln2_buf, src, len);
+	} else if (bpw <= 16) {
+		__le16 *d = (__le16 *)dln2_buf;
+		u16 *s = (u16 *)src;
+
+		len = len / 2;
+		while (len--)
+			*d++ = cpu_to_le16p(s++);
+	} else {
+		__le32 *d = (__le32 *)dln2_buf;
+		u32 *s = (u32 *)src;
+
+		len = len / 4;
+		while (len--)
+			*d++ = cpu_to_le32p(s++);
+	}
+#endif
+
+	return 0;
+}
+
+/*
+ * Copy the data from DLN2 buffer and convert to CPU byte order since the DLN2
+ * buffer is LE ordered. SPI core makes sure that the data length is a multiple
+ * of word size. The RX dln2_buf is 2 byte aligned so, for BE, we have to make
+ * sure we avoid unaligned accesses for 32 bit case.
+ */
+static int dln2_spi_copy_from_buf(u8 *dest, const u8 *dln2_buf, u16 len, u8 bpw)
+{
+#ifdef __LITTLE_ENDIAN
+	memcpy(dest, dln2_buf, len);
+#else
+	if (bpw <= 8) {
+		memcpy(dest, dln2_buf, len);
+	} else if (bpw <= 16) {
+		u16 *d = (u16 *)dest;
+		__le16 *s = (__le16 *)dln2_buf;
+
+		len = len / 2;
+		while (len--)
+			*d++ = le16_to_cpup(s++);
+	} else {
+		u32 *d = (u32 *)dest;
+		__le32 *s = (__le32 *)dln2_buf;
+
+		len = len / 4;
+		while (len--)
+			*d++ = get_unaligned_le32(s++);
+	}
+#endif
+
+	return 0;
+}
+
+/*
+ * Perform one write operation.
+ */
+static int dln2_spi_write_one(struct dln2_spi *dln2, const u8 *data,
+			      u16 data_len, u8 attr)
+{
+	struct {
+		u8 port;
+		__le16 size;
+		u8 attr;
+		u8 buf[DLN2_SPI_MAX_XFER_SIZE];
+	} __packed *tx = dln2->buf;
+	unsigned tx_len;
+
+	BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE);
+
+	if (data_len > DLN2_SPI_MAX_XFER_SIZE)
+		return -EINVAL;
+
+	tx->port = dln2->port;
+	tx->size = cpu_to_le16(data_len);
+	tx->attr = attr;
+
+	dln2_spi_copy_to_buf(tx->buf, data, data_len, dln2->bpw);
+
+	tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE;
+	return dln2_transfer_tx(dln2->pdev, DLN2_SPI_WRITE, tx, tx_len);
+}
+
+/*
+ * Perform one read operation.
+ */
+static int dln2_spi_read_one(struct dln2_spi *dln2, u8 *data,
+			     u16 data_len, u8 attr)
+{
+	int ret;
+	struct {
+		u8 port;
+		__le16 size;
+		u8 attr;
+	} __packed tx;
+	struct {
+		__le16 size;
+		u8 buf[DLN2_SPI_MAX_XFER_SIZE];
+	} __packed *rx = dln2->buf;
+	unsigned rx_len = sizeof(*rx);
+
+	BUILD_BUG_ON(sizeof(*rx) > DLN2_SPI_BUF_SIZE);
+
+	if (data_len > DLN2_SPI_MAX_XFER_SIZE)
+		return -EINVAL;
+
+	tx.port = dln2->port;
+	tx.size = cpu_to_le16(data_len);
+	tx.attr = attr;
+
+	ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ, &tx, sizeof(tx),
+			    rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(rx->size) + data_len)
+		return -EPROTO;
+	if (le16_to_cpu(rx->size) != data_len)
+		return -EPROTO;
+
+	dln2_spi_copy_from_buf(data, rx->buf, data_len, dln2->bpw);
+
+	return 0;
+}
+
+/*
+ * Perform one write & read operation.
+ */
+static int dln2_spi_read_write_one(struct dln2_spi *dln2, const u8 *tx_data,
+				   u8 *rx_data, u16 data_len, u8 attr)
+{
+	int ret;
+	struct {
+		u8 port;
+		__le16 size;
+		u8 attr;
+		u8 buf[DLN2_SPI_MAX_XFER_SIZE];
+	} __packed *tx;
+	struct {
+		__le16 size;
+		u8 buf[DLN2_SPI_MAX_XFER_SIZE];
+	} __packed *rx;
+	unsigned tx_len, rx_len;
+
+	BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE ||
+		     sizeof(*rx) > DLN2_SPI_BUF_SIZE);
+
+	if (data_len > DLN2_SPI_MAX_XFER_SIZE)
+		return -EINVAL;
+
+	/*
+	 * Since this is a pseudo full-duplex communication, we're perfectly
+	 * safe to use the same buffer for both tx and rx. When DLN2 sends the
+	 * response back, with the rx data, we don't need the tx buffer anymore.
+	 */
+	tx = dln2->buf;
+	rx = dln2->buf;
+
+	tx->port = dln2->port;
+	tx->size = cpu_to_le16(data_len);
+	tx->attr = attr;
+
+	dln2_spi_copy_to_buf(tx->buf, tx_data, data_len, dln2->bpw);
+
+	tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE;
+	rx_len = sizeof(*rx);
+
+	ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ_WRITE, tx, tx_len,
+			    rx, &rx_len);
+	if (ret < 0)
+		return ret;
+	if (rx_len < sizeof(rx->size) + data_len)
+		return -EPROTO;
+	if (le16_to_cpu(rx->size) != data_len)
+		return -EPROTO;
+
+	dln2_spi_copy_from_buf(rx_data, rx->buf, data_len, dln2->bpw);
+
+	return 0;
+}
+
+/*
+ * Read/Write wrapper. It will automatically split an operation into multiple
+ * single ones due to device buffer constraints.
+ */
+static int dln2_spi_rdwr(struct dln2_spi *dln2, const u8 *tx_data,
+			 u8 *rx_data, u16 data_len, u8 attr)
+{
+	int ret;
+	u16 len;
+	u8 temp_attr;
+	u16 remaining = data_len;
+	u16 offset;
+
+	do {
+		if (remaining > DLN2_SPI_MAX_XFER_SIZE) {
+			len = DLN2_SPI_MAX_XFER_SIZE;
+			temp_attr = DLN2_SPI_ATTR_LEAVE_SS_LOW;
+		} else {
+			len = remaining;
+			temp_attr = attr;
+		}
+
+		offset = data_len - remaining;
+
+		if (tx_data && rx_data) {
+			ret = dln2_spi_read_write_one(dln2,
+						      tx_data + offset,
+						      rx_data + offset,
+						      len, temp_attr);
+		} else if (tx_data) {
+			ret = dln2_spi_write_one(dln2,
+						 tx_data + offset,
+						 len, temp_attr);
+		} else if (rx_data) {
+			ret = dln2_spi_read_one(dln2,
+						rx_data + offset,
+						len, temp_attr);
+		 } else {
+			return -EINVAL;
+		 }
+
+		if (ret < 0)
+			return ret;
+
+		remaining -= len;
+	} while (remaining);
+
+	return 0;
+}
+
+static int dln2_spi_prepare_message(struct spi_master *master,
+				    struct spi_message *message)
+{
+	int ret;
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+	struct spi_device *spi = message->spi;
+
+	if (dln2->cs != spi->chip_select) {
+		ret = dln2_spi_cs_set_one(dln2, spi->chip_select);
+		if (ret < 0)
+			return ret;
+
+		dln2->cs = spi->chip_select;
+	}
+
+	return 0;
+}
+
+static int dln2_spi_transfer_setup(struct dln2_spi *dln2, u32 speed,
+				   u8 bpw, u8 mode)
+{
+	int ret;
+	bool bus_setup_change;
+
+	bus_setup_change = dln2->speed != speed || dln2->mode != mode ||
+			   dln2->bpw != bpw;
+
+	if (!bus_setup_change)
+		return 0;
+
+	ret = dln2_spi_enable(dln2, false);
+	if (ret < 0)
+		return ret;
+
+	if (dln2->speed != speed) {
+		ret = dln2_spi_set_speed(dln2, speed);
+		if (ret < 0)
+			return ret;
+
+		dln2->speed = speed;
+	}
+
+	if (dln2->mode != mode) {
+		ret = dln2_spi_set_mode(dln2, mode & 0x3);
+		if (ret < 0)
+			return ret;
+
+		dln2->mode = mode;
+	}
+
+	if (dln2->bpw != bpw) {
+		ret = dln2_spi_set_bpw(dln2, bpw);
+		if (ret < 0)
+			return ret;
+
+		dln2->bpw = bpw;
+	}
+
+	return dln2_spi_enable(dln2, true);
+}
+
+static int dln2_spi_transfer_one(struct spi_master *master,
+				 struct spi_device *spi,
+				 struct spi_transfer *xfer)
+{
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+	int status;
+	u8 attr = 0;
+
+	status = dln2_spi_transfer_setup(dln2, xfer->speed_hz,
+					 xfer->bits_per_word,
+					 spi->mode);
+	if (status < 0) {
+		dev_err(&dln2->pdev->dev, "Cannot setup transfer\n");
+		return status;
+	}
+
+	if (!xfer->cs_change && !spi_transfer_is_last(master, xfer))
+		attr = DLN2_SPI_ATTR_LEAVE_SS_LOW;
+
+	status = dln2_spi_rdwr(dln2, xfer->tx_buf, xfer->rx_buf,
+			       xfer->len, attr);
+	if (status < 0)
+		dev_err(&dln2->pdev->dev, "write/read failed!\n");
+
+	return status;
+}
+
+static int dln2_spi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct dln2_spi *dln2;
+	struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*dln2));
+	if (!master)
+		return -ENOMEM;
+
+	device_set_node(&master->dev, dev_fwnode(dev));
+
+	platform_set_drvdata(pdev, master);
+
+	dln2 = spi_master_get_devdata(master);
+
+	dln2->buf = devm_kmalloc(&pdev->dev, DLN2_SPI_BUF_SIZE, GFP_KERNEL);
+	if (!dln2->buf) {
+		ret = -ENOMEM;
+		goto exit_free_master;
+	}
+
+	dln2->master = master;
+	dln2->pdev = pdev;
+	dln2->port = pdata->port;
+	/* cs/mode can never be 0xff, so the first transfer will set them */
+	dln2->cs = 0xff;
+	dln2->mode = 0xff;
+
+	/* disable SPI module before continuing with the setup */
+	ret = dln2_spi_enable(dln2, false);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to disable SPI module\n");
+		goto exit_free_master;
+	}
+
+	ret = dln2_spi_get_cs_num(dln2, &master->num_chipselect);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to get number of CS pins\n");
+		goto exit_free_master;
+	}
+
+	ret = dln2_spi_get_speed_range(dln2,
+				       &master->min_speed_hz,
+				       &master->max_speed_hz);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to read bus min/max freqs\n");
+		goto exit_free_master;
+	}
+
+	ret = dln2_spi_get_supported_frame_sizes(dln2,
+						 &master->bits_per_word_mask);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to read supported frame sizes\n");
+		goto exit_free_master;
+	}
+
+	ret = dln2_spi_cs_enable_all(dln2, true);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to enable CS pins\n");
+		goto exit_free_master;
+	}
+
+	master->bus_num = -1;
+	master->mode_bits = SPI_CPOL | SPI_CPHA;
+	master->prepare_message = dln2_spi_prepare_message;
+	master->transfer_one = dln2_spi_transfer_one;
+	master->auto_runtime_pm = true;
+
+	/* enable SPI module, we're good to go */
+	ret = dln2_spi_enable(dln2, true);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to enable SPI module\n");
+		goto exit_free_master;
+	}
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev,
+					 DLN2_RPM_AUTOSUSPEND_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to register master\n");
+		goto exit_register;
+	}
+
+	return ret;
+
+exit_register:
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
+
+	if (dln2_spi_enable(dln2, false) < 0)
+		dev_err(&pdev->dev, "Failed to disable SPI module\n");
+exit_free_master:
+	spi_master_put(master);
+
+	return ret;
+}
+
+static int dln2_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+
+	pm_runtime_disable(&pdev->dev);
+
+	if (dln2_spi_enable(dln2, false) < 0)
+		dev_err(&pdev->dev, "Failed to disable SPI module\n");
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dln2_spi_suspend(struct device *dev)
+{
+	int ret;
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+
+	ret = spi_master_suspend(master);
+	if (ret < 0)
+		return ret;
+
+	if (!pm_runtime_suspended(dev)) {
+		ret = dln2_spi_enable(dln2, false);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * USB power may be cut off during sleep. Resetting the following
+	 * parameters will force the board to be set up before first transfer.
+	 */
+	dln2->cs = 0xff;
+	dln2->speed = 0;
+	dln2->bpw = 0;
+	dln2->mode = 0xff;
+
+	return 0;
+}
+
+static int dln2_spi_resume(struct device *dev)
+{
+	int ret;
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+
+	if (!pm_runtime_suspended(dev)) {
+		ret = dln2_spi_cs_enable_all(dln2, true);
+		if (ret < 0)
+			return ret;
+
+		ret = dln2_spi_enable(dln2, true);
+		if (ret < 0)
+			return ret;
+	}
+
+	return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int dln2_spi_runtime_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+
+	return dln2_spi_enable(dln2, false);
+}
+
+static int dln2_spi_runtime_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct dln2_spi *dln2 = spi_master_get_devdata(master);
+
+	return  dln2_spi_enable(dln2, true);
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops dln2_spi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(dln2_spi_suspend, dln2_spi_resume)
+	SET_RUNTIME_PM_OPS(dln2_spi_runtime_suspend,
+			   dln2_spi_runtime_resume, NULL)
+};
+
+static struct platform_driver spi_dln2_driver = {
+	.driver = {
+		.name	= "dln2-spi",
+		.pm	= &dln2_spi_pm,
+	},
+	.probe		= dln2_spi_probe,
+	.remove		= dln2_spi_remove,
+};
+module_platform_driver(spi_dln2_driver);
+
+MODULE_DESCRIPTION("Driver for the Diolan DLN2 SPI master interface");
+MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:dln2-spi");