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, 540 insertions, 0 deletions

diff --git a/drivers/media/platform/ti/omap3isp/isphist.c b/drivers/media/platform/ti/omap3isp/isphist.c
new file mode 100644
index 000000000..0ef78aace
--- /dev/null
+++ b/drivers/media/platform/ti/omap3isp/isphist.c
@@ -0,0 +1,540 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * isphist.c
+ *
+ * TI OMAP3 ISP - Histogram module
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ * Copyright (C) 2009 Texas Instruments, Inc.
+ *
+ * Contacts: David Cohen <dacohen@gmail.com>
+ *	     Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *	     Sakari Ailus <sakari.ailus@iki.fi>
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include "isp.h"
+#include "ispreg.h"
+#include "isphist.h"
+
+#define HIST_CONFIG_DMA	1
+
+/*
+ * hist_reset_mem - clear Histogram memory before start stats engine.
+ */
+static void hist_reset_mem(struct ispstat *hist)
+{
+	struct isp_device *isp = hist->isp;
+	struct omap3isp_hist_config *conf = hist->priv;
+	unsigned int i;
+
+	isp_reg_writel(isp, 0, OMAP3_ISP_IOMEM_HIST, ISPHIST_ADDR);
+
+	/*
+	 * By setting it, the histogram internal buffer is being cleared at the
+	 * same time it's being read. This bit must be cleared afterwards.
+	 */
+	isp_reg_set(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT, ISPHIST_CNT_CLEAR);
+
+	/*
+	 * We'll clear 4 words at each iteration for optimization. It avoids
+	 * 3/4 of the jumps. We also know HIST_MEM_SIZE is divisible by 4.
+	 */
+	for (i = OMAP3ISP_HIST_MEM_SIZE / 4; i > 0; i--) {
+		isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+	}
+	isp_reg_clr(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT, ISPHIST_CNT_CLEAR);
+
+	hist->wait_acc_frames = conf->num_acc_frames;
+}
+
+/*
+ * hist_setup_regs - Helper function to update Histogram registers.
+ */
+static void hist_setup_regs(struct ispstat *hist, void *priv)
+{
+	struct isp_device *isp = hist->isp;
+	struct omap3isp_hist_config *conf = priv;
+	int c;
+	u32 cnt;
+	u32 wb_gain;
+	u32 reg_hor[OMAP3ISP_HIST_MAX_REGIONS];
+	u32 reg_ver[OMAP3ISP_HIST_MAX_REGIONS];
+
+	if (!hist->update || hist->state == ISPSTAT_DISABLED ||
+	    hist->state == ISPSTAT_DISABLING)
+		return;
+
+	cnt = conf->cfa << ISPHIST_CNT_CFA_SHIFT;
+
+	wb_gain = conf->wg[0] << ISPHIST_WB_GAIN_WG00_SHIFT;
+	wb_gain |= conf->wg[1] << ISPHIST_WB_GAIN_WG01_SHIFT;
+	wb_gain |= conf->wg[2] << ISPHIST_WB_GAIN_WG02_SHIFT;
+	if (conf->cfa == OMAP3ISP_HIST_CFA_BAYER)
+		wb_gain |= conf->wg[3] << ISPHIST_WB_GAIN_WG03_SHIFT;
+
+	/* Regions size and position */
+	for (c = 0; c < OMAP3ISP_HIST_MAX_REGIONS; c++) {
+		if (c < conf->num_regions) {
+			reg_hor[c] = (conf->region[c].h_start <<
+				     ISPHIST_REG_START_SHIFT)
+				   | (conf->region[c].h_end <<
+				     ISPHIST_REG_END_SHIFT);
+			reg_ver[c] = (conf->region[c].v_start <<
+				     ISPHIST_REG_START_SHIFT)
+				   | (conf->region[c].v_end <<
+				     ISPHIST_REG_END_SHIFT);
+		} else {
+			reg_hor[c] = 0;
+			reg_ver[c] = 0;
+		}
+	}
+
+	cnt |= conf->hist_bins << ISPHIST_CNT_BINS_SHIFT;
+	switch (conf->hist_bins) {
+	case OMAP3ISP_HIST_BINS_256:
+		cnt |= (ISPHIST_IN_BIT_WIDTH_CCDC - 8) <<
+			ISPHIST_CNT_SHIFT_SHIFT;
+		break;
+	case OMAP3ISP_HIST_BINS_128:
+		cnt |= (ISPHIST_IN_BIT_WIDTH_CCDC - 7) <<
+			ISPHIST_CNT_SHIFT_SHIFT;
+		break;
+	case OMAP3ISP_HIST_BINS_64:
+		cnt |= (ISPHIST_IN_BIT_WIDTH_CCDC - 6) <<
+			ISPHIST_CNT_SHIFT_SHIFT;
+		break;
+	default: /* OMAP3ISP_HIST_BINS_32 */
+		cnt |= (ISPHIST_IN_BIT_WIDTH_CCDC - 5) <<
+			ISPHIST_CNT_SHIFT_SHIFT;
+		break;
+	}
+
+	hist_reset_mem(hist);
+
+	isp_reg_writel(isp, cnt, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT);
+	isp_reg_writel(isp, wb_gain,  OMAP3_ISP_IOMEM_HIST, ISPHIST_WB_GAIN);
+	isp_reg_writel(isp, reg_hor[0], OMAP3_ISP_IOMEM_HIST, ISPHIST_R0_HORZ);
+	isp_reg_writel(isp, reg_ver[0], OMAP3_ISP_IOMEM_HIST, ISPHIST_R0_VERT);
+	isp_reg_writel(isp, reg_hor[1], OMAP3_ISP_IOMEM_HIST, ISPHIST_R1_HORZ);
+	isp_reg_writel(isp, reg_ver[1], OMAP3_ISP_IOMEM_HIST, ISPHIST_R1_VERT);
+	isp_reg_writel(isp, reg_hor[2], OMAP3_ISP_IOMEM_HIST, ISPHIST_R2_HORZ);
+	isp_reg_writel(isp, reg_ver[2], OMAP3_ISP_IOMEM_HIST, ISPHIST_R2_VERT);
+	isp_reg_writel(isp, reg_hor[3], OMAP3_ISP_IOMEM_HIST, ISPHIST_R3_HORZ);
+	isp_reg_writel(isp, reg_ver[3], OMAP3_ISP_IOMEM_HIST, ISPHIST_R3_VERT);
+
+	hist->update = 0;
+	hist->config_counter += hist->inc_config;
+	hist->inc_config = 0;
+	hist->buf_size = conf->buf_size;
+}
+
+static void hist_enable(struct ispstat *hist, int enable)
+{
+	if (enable) {
+		isp_reg_set(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_PCR,
+			    ISPHIST_PCR_ENABLE);
+		omap3isp_subclk_enable(hist->isp, OMAP3_ISP_SUBCLK_HIST);
+	} else {
+		isp_reg_clr(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_PCR,
+			    ISPHIST_PCR_ENABLE);
+		omap3isp_subclk_disable(hist->isp, OMAP3_ISP_SUBCLK_HIST);
+	}
+}
+
+static int hist_busy(struct ispstat *hist)
+{
+	return isp_reg_readl(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_PCR)
+						& ISPHIST_PCR_BUSY;
+}
+
+static void hist_dma_cb(void *data)
+{
+	struct ispstat *hist = data;
+
+	/* FIXME: The DMA engine API can't report transfer errors :-/ */
+
+	isp_reg_clr(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT,
+		    ISPHIST_CNT_CLEAR);
+
+	omap3isp_stat_dma_isr(hist);
+	if (hist->state != ISPSTAT_DISABLED)
+		omap3isp_hist_dma_done(hist->isp);
+}
+
+static int hist_buf_dma(struct ispstat *hist)
+{
+	dma_addr_t dma_addr = hist->active_buf->dma_addr;
+	struct dma_async_tx_descriptor *tx;
+	struct dma_slave_config cfg;
+	dma_cookie_t cookie;
+	int ret;
+
+	if (unlikely(!dma_addr)) {
+		dev_dbg(hist->isp->dev, "hist: invalid DMA buffer address\n");
+		goto error;
+	}
+
+	isp_reg_writel(hist->isp, 0, OMAP3_ISP_IOMEM_HIST, ISPHIST_ADDR);
+	isp_reg_set(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT,
+		    ISPHIST_CNT_CLEAR);
+	omap3isp_flush(hist->isp);
+
+	memset(&cfg, 0, sizeof(cfg));
+	cfg.src_addr = hist->isp->mmio_hist_base_phys + ISPHIST_DATA;
+	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.src_maxburst = hist->buf_size / 4;
+
+	ret = dmaengine_slave_config(hist->dma_ch, &cfg);
+	if (ret < 0) {
+		dev_dbg(hist->isp->dev,
+			"hist: DMA slave configuration failed\n");
+		goto error;
+	}
+
+	tx = dmaengine_prep_slave_single(hist->dma_ch, dma_addr,
+					 hist->buf_size, DMA_DEV_TO_MEM,
+					 DMA_CTRL_ACK);
+	if (tx == NULL) {
+		dev_dbg(hist->isp->dev,
+			"hist: DMA slave preparation failed\n");
+		goto error;
+	}
+
+	tx->callback = hist_dma_cb;
+	tx->callback_param = hist;
+	cookie = tx->tx_submit(tx);
+	if (dma_submit_error(cookie)) {
+		dev_dbg(hist->isp->dev, "hist: DMA submission failed\n");
+		goto error;
+	}
+
+	dma_async_issue_pending(hist->dma_ch);
+
+	return STAT_BUF_WAITING_DMA;
+
+error:
+	hist_reset_mem(hist);
+	return STAT_NO_BUF;
+}
+
+static int hist_buf_pio(struct ispstat *hist)
+{
+	struct isp_device *isp = hist->isp;
+	u32 *buf = hist->active_buf->virt_addr;
+	unsigned int i;
+
+	if (!buf) {
+		dev_dbg(isp->dev, "hist: invalid PIO buffer address\n");
+		hist_reset_mem(hist);
+		return STAT_NO_BUF;
+	}
+
+	isp_reg_writel(isp, 0, OMAP3_ISP_IOMEM_HIST, ISPHIST_ADDR);
+
+	/*
+	 * By setting it, the histogram internal buffer is being cleared at the
+	 * same time it's being read. This bit must be cleared just after all
+	 * data is acquired.
+	 */
+	isp_reg_set(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT, ISPHIST_CNT_CLEAR);
+
+	/*
+	 * We'll read 4 times a 4-bytes-word at each iteration for
+	 * optimization. It avoids 3/4 of the jumps. We also know buf_size is
+	 * divisible by 16.
+	 */
+	for (i = hist->buf_size / 16; i > 0; i--) {
+		*buf++ = isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		*buf++ = isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		*buf++ = isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+		*buf++ = isp_reg_readl(isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_DATA);
+	}
+	isp_reg_clr(hist->isp, OMAP3_ISP_IOMEM_HIST, ISPHIST_CNT,
+		    ISPHIST_CNT_CLEAR);
+
+	return STAT_BUF_DONE;
+}
+
+/*
+ * hist_buf_process - Callback from ISP driver for HIST interrupt.
+ */
+static int hist_buf_process(struct ispstat *hist)
+{
+	struct omap3isp_hist_config *user_cfg = hist->priv;
+	int ret;
+
+	if (atomic_read(&hist->buf_err) || hist->state != ISPSTAT_ENABLED) {
+		hist_reset_mem(hist);
+		return STAT_NO_BUF;
+	}
+
+	if (--(hist->wait_acc_frames))
+		return STAT_NO_BUF;
+
+	if (hist->dma_ch)
+		ret = hist_buf_dma(hist);
+	else
+		ret = hist_buf_pio(hist);
+
+	hist->wait_acc_frames = user_cfg->num_acc_frames;
+
+	return ret;
+}
+
+static u32 hist_get_buf_size(struct omap3isp_hist_config *conf)
+{
+	return OMAP3ISP_HIST_MEM_SIZE_BINS(conf->hist_bins) * conf->num_regions;
+}
+
+/*
+ * hist_validate_params - Helper function to check user given params.
+ * @new_conf: Pointer to user configuration structure.
+ *
+ * Returns 0 on success configuration.
+ */
+static int hist_validate_params(struct ispstat *hist, void *new_conf)
+{
+	struct omap3isp_hist_config *user_cfg = new_conf;
+	int c;
+	u32 buf_size;
+
+	if (user_cfg->cfa > OMAP3ISP_HIST_CFA_FOVEONX3)
+		return -EINVAL;
+
+	/* Regions size and position */
+
+	if ((user_cfg->num_regions < OMAP3ISP_HIST_MIN_REGIONS) ||
+	    (user_cfg->num_regions > OMAP3ISP_HIST_MAX_REGIONS))
+		return -EINVAL;
+
+	/* Regions */
+	for (c = 0; c < user_cfg->num_regions; c++) {
+		if (user_cfg->region[c].h_start & ~ISPHIST_REG_START_END_MASK)
+			return -EINVAL;
+		if (user_cfg->region[c].h_end & ~ISPHIST_REG_START_END_MASK)
+			return -EINVAL;
+		if (user_cfg->region[c].v_start & ~ISPHIST_REG_START_END_MASK)
+			return -EINVAL;
+		if (user_cfg->region[c].v_end & ~ISPHIST_REG_START_END_MASK)
+			return -EINVAL;
+		if (user_cfg->region[c].h_start > user_cfg->region[c].h_end)
+			return -EINVAL;
+		if (user_cfg->region[c].v_start > user_cfg->region[c].v_end)
+			return -EINVAL;
+	}
+
+	switch (user_cfg->num_regions) {
+	case 1:
+		if (user_cfg->hist_bins > OMAP3ISP_HIST_BINS_256)
+			return -EINVAL;
+		break;
+	case 2:
+		if (user_cfg->hist_bins > OMAP3ISP_HIST_BINS_128)
+			return -EINVAL;
+		break;
+	default: /* 3 or 4 */
+		if (user_cfg->hist_bins > OMAP3ISP_HIST_BINS_64)
+			return -EINVAL;
+		break;
+	}
+
+	buf_size = hist_get_buf_size(user_cfg);
+	if (buf_size > user_cfg->buf_size)
+		/* User's buf_size request wasn't enough */
+		user_cfg->buf_size = buf_size;
+	else if (user_cfg->buf_size > OMAP3ISP_HIST_MAX_BUF_SIZE)
+		user_cfg->buf_size = OMAP3ISP_HIST_MAX_BUF_SIZE;
+
+	return 0;
+}
+
+static int hist_comp_params(struct ispstat *hist,
+			    struct omap3isp_hist_config *user_cfg)
+{
+	struct omap3isp_hist_config *cur_cfg = hist->priv;
+	int c;
+
+	if (cur_cfg->cfa != user_cfg->cfa)
+		return 1;
+
+	if (cur_cfg->num_acc_frames != user_cfg->num_acc_frames)
+		return 1;
+
+	if (cur_cfg->hist_bins != user_cfg->hist_bins)
+		return 1;
+
+	for (c = 0; c < OMAP3ISP_HIST_MAX_WG; c++) {
+		if (c == 3 && user_cfg->cfa == OMAP3ISP_HIST_CFA_FOVEONX3)
+			break;
+		else if (cur_cfg->wg[c] != user_cfg->wg[c])
+			return 1;
+	}
+
+	if (cur_cfg->num_regions != user_cfg->num_regions)
+		return 1;
+
+	/* Regions */
+	for (c = 0; c < user_cfg->num_regions; c++) {
+		if (cur_cfg->region[c].h_start != user_cfg->region[c].h_start)
+			return 1;
+		if (cur_cfg->region[c].h_end != user_cfg->region[c].h_end)
+			return 1;
+		if (cur_cfg->region[c].v_start != user_cfg->region[c].v_start)
+			return 1;
+		if (cur_cfg->region[c].v_end != user_cfg->region[c].v_end)
+			return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * hist_update_params - Helper function to check and store user given params.
+ * @new_conf: Pointer to user configuration structure.
+ */
+static void hist_set_params(struct ispstat *hist, void *new_conf)
+{
+	struct omap3isp_hist_config *user_cfg = new_conf;
+	struct omap3isp_hist_config *cur_cfg = hist->priv;
+
+	if (!hist->configured || hist_comp_params(hist, user_cfg)) {
+		memcpy(cur_cfg, user_cfg, sizeof(*user_cfg));
+		if (user_cfg->num_acc_frames == 0)
+			user_cfg->num_acc_frames = 1;
+		hist->inc_config++;
+		hist->update = 1;
+		/*
+		 * User might be asked for a bigger buffer than necessary for
+		 * this configuration. In order to return the right amount of
+		 * data during buffer request, let's calculate the size here
+		 * instead of stick with user_cfg->buf_size.
+		 */
+		cur_cfg->buf_size = hist_get_buf_size(cur_cfg);
+
+	}
+}
+
+static long hist_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
+{
+	struct ispstat *stat = v4l2_get_subdevdata(sd);
+
+	switch (cmd) {
+	case VIDIOC_OMAP3ISP_HIST_CFG:
+		return omap3isp_stat_config(stat, arg);
+	case VIDIOC_OMAP3ISP_STAT_REQ:
+		return omap3isp_stat_request_statistics(stat, arg);
+	case VIDIOC_OMAP3ISP_STAT_REQ_TIME32:
+		return omap3isp_stat_request_statistics_time32(stat, arg);
+	case VIDIOC_OMAP3ISP_STAT_EN: {
+		int *en = arg;
+		return omap3isp_stat_enable(stat, !!*en);
+	}
+	}
+
+	return -ENOIOCTLCMD;
+
+}
+
+static const struct ispstat_ops hist_ops = {
+	.validate_params	= hist_validate_params,
+	.set_params		= hist_set_params,
+	.setup_regs		= hist_setup_regs,
+	.enable			= hist_enable,
+	.busy			= hist_busy,
+	.buf_process		= hist_buf_process,
+};
+
+static const struct v4l2_subdev_core_ops hist_subdev_core_ops = {
+	.ioctl = hist_ioctl,
+	.subscribe_event = omap3isp_stat_subscribe_event,
+	.unsubscribe_event = omap3isp_stat_unsubscribe_event,
+};
+
+static const struct v4l2_subdev_video_ops hist_subdev_video_ops = {
+	.s_stream = omap3isp_stat_s_stream,
+};
+
+static const struct v4l2_subdev_ops hist_subdev_ops = {
+	.core = &hist_subdev_core_ops,
+	.video = &hist_subdev_video_ops,
+};
+
+/*
+ * omap3isp_hist_init - Module Initialization.
+ */
+int omap3isp_hist_init(struct isp_device *isp)
+{
+	struct ispstat *hist = &isp->isp_hist;
+	struct omap3isp_hist_config *hist_cfg;
+	int ret;
+
+	hist_cfg = kzalloc(sizeof(*hist_cfg), GFP_KERNEL);
+	if (hist_cfg == NULL)
+		return -ENOMEM;
+
+	hist->isp = isp;
+
+	if (HIST_CONFIG_DMA) {
+		dma_cap_mask_t mask;
+
+		/*
+		 * We need slave capable channel without DMA request line for
+		 * reading out the data.
+		 * For this we can use dma_request_chan_by_mask() as we are
+		 * happy with any channel as long as it is capable of slave
+		 * configuration.
+		 */
+		dma_cap_zero(mask);
+		dma_cap_set(DMA_SLAVE, mask);
+		hist->dma_ch = dma_request_chan_by_mask(&mask);
+		if (IS_ERR(hist->dma_ch)) {
+			ret = PTR_ERR(hist->dma_ch);
+			if (ret == -EPROBE_DEFER)
+				goto err;
+
+			hist->dma_ch = NULL;
+			dev_warn(isp->dev,
+				 "hist: DMA channel request failed, using PIO\n");
+		} else {
+			dev_dbg(isp->dev, "hist: using DMA channel %s\n",
+				dma_chan_name(hist->dma_ch));
+		}
+	}
+
+	hist->ops = &hist_ops;
+	hist->priv = hist_cfg;
+	hist->event_type = V4L2_EVENT_OMAP3ISP_HIST;
+
+	ret = omap3isp_stat_init(hist, "histogram", &hist_subdev_ops);
+
+err:
+	if (ret) {
+		if (!IS_ERR_OR_NULL(hist->dma_ch))
+			dma_release_channel(hist->dma_ch);
+		kfree(hist_cfg);
+	}
+
+	return ret;
+}
+
+/*
+ * omap3isp_hist_cleanup - Module cleanup.
+ */
+void omap3isp_hist_cleanup(struct isp_device *isp)
+{
+	struct ispstat *hist = &isp->isp_hist;
+
+	if (hist->dma_ch)
+		dma_release_channel(hist->dma_ch);
+
+	omap3isp_stat_cleanup(hist);
+}