Staging: most: add MOST driver's hdm-dim2 module

This patch adds the hdm-dim2 module of the MOST driver to the kernel's
driver staging area. This module is part of the MOST driver and handles
the MediaLB interface of the MOST network interface controller.

This patch is needed in order to use the MediaLB peripheral interface of
the network interface controller.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

10 files changed, 2451 insertions, 0 deletions

diff --git a/drivers/staging/most/hdm-dim2/Kconfig b/drivers/staging/most/hdm-dim2/Kconfig
new file mode 100644
index 000000000000..4abeb545955e
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/Kconfig
@@ -0,0 +1,15 @@
+#
+# MediaLB configuration
+#
+
+config HDM_DIM2
+	tristate "DIM2 HDM"
+
+	---help---
+	  Say Y here if you want to connect via MediaLB to network tranceiver.
+	  This device driver is platform dependent and needs an addtional
+	  platform driver to be installed. For more information contact
+	  maintainer of this driver.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called hdm_dim2.
diff --git a/drivers/staging/most/hdm-dim2/Makefile b/drivers/staging/most/hdm-dim2/Makefile
new file mode 100644
index 000000000000..6bbee879a8ea
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/Makefile
@@ -0,0 +1,5 @@
+obj-$(CONFIG_HDM_DIM2) += hdm_dim2.o
+
+hdm_dim2-objs := dim2_hdm.o dim2_hal.o dim2_sysfs.o
+ccflags-y += -Idrivers/staging/most/mostcore/
+ccflags-y += -Idrivers/staging/most/aim-network/
diff --git a/drivers/staging/most/hdm-dim2/dim2_errors.h b/drivers/staging/most/hdm-dim2/dim2_errors.h
new file mode 100644
index 000000000000..314f7de2be73
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_errors.h
@@ -0,0 +1,67 @@
+/*
+ * dim2_errors.h - Definitions of errors for DIM2 HAL API
+ * (MediaLB, Device Interface Macro IP, OS62420)
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#ifndef _MOST_DIM_ERRORS_H
+#define _MOST_DIM_ERRORS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/**
+ * MOST DIM errors.
+ */
+enum dim_errors_t {
+	/** Not an error */
+	DIM_NO_ERROR = 0,
+
+	/** Bad base address for DIM2 IP */
+	DIM_INIT_ERR_DIM_ADDR = 0x10,
+
+	/**< Bad MediaLB clock */
+	DIM_INIT_ERR_MLB_CLOCK,
+
+	/** Bad channel address */
+	DIM_INIT_ERR_CHANNEL_ADDRESS,
+
+	/** Out of DBR memory */
+	DIM_INIT_ERR_OUT_OF_MEMORY,
+
+	/** DIM API is called while DIM is not initialized successfully */
+	DIM_ERR_DRIVER_NOT_INITIALIZED = 0x20,
+
+	/**
+	 * Configuration does not respect hardware limitations
+	 * for isochronous or synchronous channels
+	 */
+	DIM_ERR_BAD_CONFIG,
+
+	/**
+	 * Buffer size does not respect hardware limitations
+	 * for isochronous or synchronous channels
+	 */
+	DIM_ERR_BAD_BUFFER_SIZE,
+
+	DIM_ERR_UNDERFLOW,
+
+	DIM_ERR_OVERFLOW,
+};
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _MOST_DIM_ERRORS_H */
diff --git a/drivers/staging/most/hdm-dim2/dim2_hal.c b/drivers/staging/most/hdm-dim2/dim2_hal.c
new file mode 100644
index 000000000000..01b748944ee4
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_hal.c
@@ -0,0 +1,919 @@
+/*
+ * dim2_hal.c - DIM2 HAL implementation
+ * (MediaLB, Device Interface Macro IP, OS62420)
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+/* Author: Andrey Shvetsov <andrey.shvetsov@k2l.de> */
+
+#include "dim2_hal.h"
+#include "dim2_errors.h"
+#include "dim2_reg.h"
+#include <linux/stddef.h>
+
+
+/*
+ * The number of frames per sub-buffer for synchronous channels.
+ * Allowed values: 1, 2, 4, 8, 16, 32, 64.
+ */
+#define FRAMES_PER_SUBBUFF 16
+
+/*
+ * Size factor for synchronous DBR buffer.
+ * Minimal value is 4*FRAMES_PER_SUBBUFF.
+ */
+#define SYNC_DBR_FACTOR (4u * (u16)FRAMES_PER_SUBBUFF)
+
+/*
+ * Size factor for isochronous DBR buffer.
+ * Minimal value is 3.
+ */
+#define ISOC_DBR_FACTOR 3u
+
+/*
+ * Number of 32-bit units for DBR map.
+ *
+ * 1: block size is 512, max allocation is 16K
+ * 2: block size is 256, max allocation is 8K
+ * 4: block size is 128, max allocation is 4K
+ * 8: block size is 64, max allocation is 2K
+ *
+ * Min allocated space is block size.
+ * Max possible allocated space is 32 blocks.
+ */
+#define DBR_MAP_SIZE 2
+
+
+/* -------------------------------------------------------------------------- */
+/* not configurable area */
+
+#define CDT 0x00
+#define ADT 0x40
+#define MLB_CAT 0x80
+#define AHB_CAT 0x88
+
+#define DBR_SIZE  (16*1024) /* specified by IP */
+#define DBR_BLOCK_SIZE  (DBR_SIZE / 32 / DBR_MAP_SIZE)
+
+
+/* -------------------------------------------------------------------------- */
+/* generic helper functions and macros */
+
+#define MLBC0_FCNT_VAL_MACRO(n) MLBC0_FCNT_VAL_ ## n ## FPSB
+#define MLBC0_FCNT_VAL(fpsb) MLBC0_FCNT_VAL_MACRO(fpsb)
+
+static inline u32 bit_mask(u8 position)
+{
+	return (u32)1 << position;
+}
+
+static inline bool dim_on_error(u8 error_id, const char *error_message)
+{
+	DIMCB_OnError(error_id, error_message);
+	return false;
+}
+
+
+/* -------------------------------------------------------------------------- */
+/* types and local variables */
+
+struct lld_global_vars_t {
+	bool dim_is_initialized;
+	bool mcm_is_initialized;
+	struct dim2_regs *dim2; /* DIM2 core base address */
+	u32 dbr_map[DBR_MAP_SIZE];
+};
+
+static struct lld_global_vars_t g = { false };
+
+
+/* -------------------------------------------------------------------------- */
+
+static int dbr_get_mask_size(u16 size)
+{
+	int i;
+
+	for (i = 0; i < 6; i++)
+		if (size <= (DBR_BLOCK_SIZE << i))
+			return 1 << i;
+	return 0;
+}
+
+/**
+ * Allocates DBR memory.
+ * @param size Allocating memory size.
+ * @return Offset in DBR memory by success or DBR_SIZE if out of memory.
+ */
+static int alloc_dbr(u16 size)
+{
+	int mask_size;
+	int i, block_idx = 0;
+
+	if (size <= 0)
+		return DBR_SIZE; /* out of memory */
+
+	mask_size = dbr_get_mask_size(size);
+	if (mask_size == 0)
+		return DBR_SIZE; /* out of memory */
+
+	for (i = 0; i < DBR_MAP_SIZE; i++) {
+		u32 const blocks = (size + DBR_BLOCK_SIZE - 1) / DBR_BLOCK_SIZE;
+		u32 mask = ~((~(u32)0) << blocks);
+
+		do {
+			if ((g.dbr_map[i] & mask) == 0) {
+				g.dbr_map[i] |= mask;
+				return block_idx * DBR_BLOCK_SIZE;
+			}
+			block_idx += mask_size;
+			/* do shift left with 2 steps for case mask_size == 32 */
+			mask <<= mask_size - 1;
+		} while ((mask <<= 1) != 0);
+	}
+
+	return DBR_SIZE; /* out of memory */
+}
+
+static void free_dbr(int offs, int size)
+{
+	int block_idx = offs / DBR_BLOCK_SIZE;
+	u32 const blocks = (size + DBR_BLOCK_SIZE - 1) / DBR_BLOCK_SIZE;
+	u32 mask = ~((~(u32)0) << blocks);
+
+	mask <<= block_idx % 32;
+	g.dbr_map[block_idx / 32] &= ~mask;
+}
+
+/* -------------------------------------------------------------------------- */
+
+static u32 dim2_read_ctr(u32 ctr_addr, u16 mdat_idx)
+{
+	DIMCB_IoWrite(&g.dim2->MADR, ctr_addr);
+
+	/* wait till transfer is completed */
+	while ((DIMCB_IoRead(&g.dim2->MCTL) & 1) != 1)
+		continue;
+
+	DIMCB_IoWrite(&g.dim2->MCTL, 0);   /* clear transfer complete */
+
+	return DIMCB_IoRead((&g.dim2->MDAT0) + mdat_idx);
+}
+
+static void dim2_write_ctr_mask(u32 ctr_addr, const u32 *mask, const u32 *value)
+{
+	enum { MADR_WNR_BIT = 31 };
+
+	DIMCB_IoWrite(&g.dim2->MCTL, 0);   /* clear transfer complete */
+
+	if (mask[0] != 0)
+		DIMCB_IoWrite(&g.dim2->MDAT0, value[0]);
+	if (mask[1] != 0)
+		DIMCB_IoWrite(&g.dim2->MDAT1, value[1]);
+	if (mask[2] != 0)
+		DIMCB_IoWrite(&g.dim2->MDAT2, value[2]);
+	if (mask[3] != 0)
+		DIMCB_IoWrite(&g.dim2->MDAT3, value[3]);
+
+	DIMCB_IoWrite(&g.dim2->MDWE0, mask[0]);
+	DIMCB_IoWrite(&g.dim2->MDWE1, mask[1]);
+	DIMCB_IoWrite(&g.dim2->MDWE2, mask[2]);
+	DIMCB_IoWrite(&g.dim2->MDWE3, mask[3]);
+
+	DIMCB_IoWrite(&g.dim2->MADR, bit_mask(MADR_WNR_BIT) | ctr_addr);
+
+	/* wait till transfer is completed */
+	while ((DIMCB_IoRead(&g.dim2->MCTL) & 1) != 1)
+		continue;
+
+	DIMCB_IoWrite(&g.dim2->MCTL, 0);   /* clear transfer complete */
+}
+
+static inline void dim2_write_ctr(u32 ctr_addr, const u32 *value)
+{
+	u32 const mask[4] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
+
+	dim2_write_ctr_mask(ctr_addr, mask, value);
+}
+
+static inline void dim2_clear_ctr(u32 ctr_addr)
+{
+	u32 const value[4] = { 0, 0, 0, 0 };
+
+	dim2_write_ctr(ctr_addr, value);
+}
+
+static void dim2_configure_cat(u8 cat_base, u8 ch_addr, u8 ch_type,
+			       bool read_not_write, bool sync_mfe)
+{
+	u16 const cat =
+		(read_not_write << CAT_RNW_BIT) |
+		(ch_type << CAT_CT_SHIFT) |
+		(ch_addr << CAT_CL_SHIFT) |
+		(sync_mfe << CAT_MFE_BIT) |
+		(false << CAT_MT_BIT) |
+		(true << CAT_CE_BIT);
+	u8 const ctr_addr = cat_base + ch_addr / 8;
+	u8 const idx = (ch_addr % 8) / 2;
+	u8 const shift = (ch_addr % 2) * 16;
+	u32 mask[4] = { 0, 0, 0, 0 };
+	u32 value[4] = { 0, 0, 0, 0 };
+
+	mask[idx] = (u32)0xFFFF << shift;
+	value[idx] = cat << shift;
+	dim2_write_ctr_mask(ctr_addr, mask, value);
+}
+
+static void dim2_clear_cat(u8 cat_base, u8 ch_addr)
+{
+	u8 const ctr_addr = cat_base + ch_addr / 8;
+	u8 const idx = (ch_addr % 8) / 2;
+	u8 const shift = (ch_addr % 2) * 16;
+	u32 mask[4] = { 0, 0, 0, 0 };
+	u32 value[4] = { 0, 0, 0, 0 };
+
+	mask[idx] = (u32)0xFFFF << shift;
+	dim2_write_ctr_mask(ctr_addr, mask, value);
+}
+
+static void dim2_configure_cdt(u8 ch_addr, u16 dbr_address, u16 hw_buffer_size,
+			       u16 packet_length)
+{
+	u32 cdt[4] = { 0, 0, 0, 0 };
+
+	if (packet_length)
+		cdt[1] = ((packet_length - 1) << CDT1_BS_ISOC_SHIFT);
+
+	cdt[3] =
+		((hw_buffer_size - 1) << CDT3_BD_SHIFT) |
+		(dbr_address << CDT3_BA_SHIFT);
+	dim2_write_ctr(CDT + ch_addr, cdt);
+}
+
+static void dim2_clear_cdt(u8 ch_addr)
+{
+	u32 cdt[4] = { 0, 0, 0, 0 };
+
+	dim2_write_ctr(CDT + ch_addr, cdt);
+}
+
+static void dim2_configure_adt(u8 ch_addr)
+{
+	u32 adt[4] = { 0, 0, 0, 0 };
+
+	adt[0] =
+		(true << ADT0_CE_BIT) |
+		(true << ADT0_LE_BIT) |
+		(0 << ADT0_PG_BIT);
+
+	dim2_write_ctr(ADT + ch_addr, adt);
+}
+
+static void dim2_clear_adt(u8 ch_addr)
+{
+	u32 adt[4] = { 0, 0, 0, 0 };
+
+	dim2_write_ctr(ADT + ch_addr, adt);
+}
+
+static void dim2_start_ctrl_async(u8 ch_addr, u8 idx, u32 buf_addr,
+				  u16 buffer_size)
+{
+	u8 const shift = idx * 16;
+
+	u32 mask[4] = { 0, 0, 0, 0 };
+	u32 adt[4] = { 0, 0, 0, 0 };
+
+	mask[1] =
+		bit_mask(ADT1_PS_BIT + shift) |
+		bit_mask(ADT1_RDY_BIT + shift) |
+		(ADT1_CTRL_ASYNC_BD_MASK << (ADT1_BD_SHIFT + shift));
+	adt[1] =
+		(true << (ADT1_PS_BIT + shift)) |
+		(true << (ADT1_RDY_BIT + shift)) |
+		((buffer_size - 1) << (ADT1_BD_SHIFT + shift));
+
+	mask[idx + 2] = 0xFFFFFFFF;
+	adt[idx + 2] = buf_addr;
+
+	dim2_write_ctr_mask(ADT + ch_addr, mask, adt);
+}
+
+static void dim2_start_isoc_sync(u8 ch_addr, u8 idx, u32 buf_addr,
+				 u16 buffer_size)
+{
+	u8 const shift = idx * 16;
+
+	u32 mask[4] = { 0, 0, 0, 0 };
+	u32 adt[4] = { 0, 0, 0, 0 };
+
+	mask[1] =
+		bit_mask(ADT1_RDY_BIT + shift) |
+		(ADT1_ISOC_SYNC_BD_MASK << (ADT1_BD_SHIFT + shift));
+	adt[1] =
+		(true << (ADT1_RDY_BIT + shift)) |
+		((buffer_size - 1) << (ADT1_BD_SHIFT + shift));
+
+	mask[idx + 2] = 0xFFFFFFFF;
+	adt[idx + 2] = buf_addr;
+
+	dim2_write_ctr_mask(ADT + ch_addr, mask, adt);
+}
+
+
+static void dim2_clear_ctram(void)
+{
+	u32 ctr_addr;
+
+	for (ctr_addr = 0; ctr_addr < 0x90; ctr_addr++)
+		dim2_clear_ctr(ctr_addr);
+}
+
+static void dim2_configure_channel(
+	u8 ch_addr, u8 type, u8 is_tx, u16 dbr_address, u16 hw_buffer_size,
+	u16 packet_length, bool sync_mfe)
+{
+	dim2_configure_cdt(ch_addr, dbr_address, hw_buffer_size, packet_length);
+	dim2_configure_cat(MLB_CAT, ch_addr, type, is_tx ? 1 : 0, sync_mfe);
+
+	dim2_configure_adt(ch_addr);
+	dim2_configure_cat(AHB_CAT, ch_addr, type, is_tx ? 0 : 1, sync_mfe);
+
+	/* unmask interrupt for used channel, enable mlb_sys_int[0] interrupt */
+	DIMCB_IoWrite(&g.dim2->ACMR0,
+		      DIMCB_IoRead(&g.dim2->ACMR0) | bit_mask(ch_addr));
+}
+
+static void dim2_clear_channel(u8 ch_addr)
+{
+	/* mask interrupt for used channel, disable mlb_sys_int[0] interrupt */
+	DIMCB_IoWrite(&g.dim2->ACMR0,
+		      DIMCB_IoRead(&g.dim2->ACMR0) & ~bit_mask(ch_addr));
+
+	dim2_clear_cat(AHB_CAT, ch_addr);
+	dim2_clear_adt(ch_addr);
+
+	dim2_clear_cat(MLB_CAT, ch_addr);
+	dim2_clear_cdt(ch_addr);
+}
+
+/* -------------------------------------------------------------------------- */
+/* channel state helpers */
+
+static void state_init(struct int_ch_state *state)
+{
+	state->request_counter = 0;
+	state->service_counter = 0;
+
+	state->idx1 = 0;
+	state->idx2 = 0;
+	state->level = 0;
+}
+
+/* -------------------------------------------------------------------------- */
+/* macro helper functions */
+
+static inline bool check_channel_address(u32 ch_address)
+{
+	return ch_address > 0 && (ch_address % 2) == 0 &&
+	       (ch_address / 2) <= (u32)CAT_CL_MASK;
+}
+
+static inline bool check_packet_length(u32 packet_length)
+{
+	u16 const max_size = ((u16)CDT3_BD_ISOC_MASK + 1u) / ISOC_DBR_FACTOR;
+
+	if (packet_length <= 0)
+		return false; /* too small */
+
+	if (packet_length > max_size)
+		return false; /* too big */
+
+	if (packet_length - 1u > (u32)CDT1_BS_ISOC_MASK)
+		return false; /* too big */
+
+	return true;
+}
+
+static inline bool check_bytes_per_frame(u32 bytes_per_frame)
+{
+	u16 const max_size = ((u16)CDT3_BD_MASK + 1u) / SYNC_DBR_FACTOR;
+
+	if (bytes_per_frame <= 0)
+		return false; /* too small */
+
+	if (bytes_per_frame > max_size)
+		return false; /* too big */
+
+	return true;
+}
+
+static inline u16 norm_ctrl_async_buffer_size(u16 buf_size)
+{
+	u16 const max_size = (u16)ADT1_CTRL_ASYNC_BD_MASK + 1u;
+
+	if (buf_size > max_size)
+		return max_size;
+
+	return buf_size;
+}
+
+static inline u16 norm_isoc_buffer_size(u16 buf_size, u16 packet_length)
+{
+	u16 n;
+	u16 const max_size = (u16)ADT1_ISOC_SYNC_BD_MASK + 1u;
+
+	if (buf_size > max_size)
+		buf_size = max_size;
+
+	n = buf_size / packet_length;
+
+	if (n < 2u)
+		return 0; /* too small buffer for given packet_length */
+
+	return packet_length * n;
+}
+
+static inline u16 norm_sync_buffer_size(u16 buf_size, u16 bytes_per_frame)
+{
+	u16 n;
+	u16 const max_size = (u16)ADT1_ISOC_SYNC_BD_MASK + 1u;
+	u32 const unit = bytes_per_frame * (u16)FRAMES_PER_SUBBUFF;
+
+	if (buf_size > max_size)
+		buf_size = max_size;
+
+	n = buf_size / unit;
+
+	if (n < 1u)
+		return 0; /* too small buffer for given bytes_per_frame */
+
+	return unit * n;
+}
+
+static void dim2_cleanup(void)
+{
+	/* disable MediaLB */
+	DIMCB_IoWrite(&g.dim2->MLBC0, false << MLBC0_MLBEN_BIT);
+
+	dim2_clear_ctram();
+
+	/* disable mlb_int interrupt */
+	DIMCB_IoWrite(&g.dim2->MIEN, 0);
+
+	/* clear status for all dma channels */
+	DIMCB_IoWrite(&g.dim2->ACSR0, 0xFFFFFFFF);
+	DIMCB_IoWrite(&g.dim2->ACSR1, 0xFFFFFFFF);
+
+	/* mask interrupts for all channels */
+	DIMCB_IoWrite(&g.dim2->ACMR0, 0);
+	DIMCB_IoWrite(&g.dim2->ACMR1, 0);
+}
+
+static void dim2_initialize(bool enable_6pin, u8 mlb_clock)
+{
+	dim2_cleanup();
+
+	/* configure and enable MediaLB */
+	DIMCB_IoWrite(&g.dim2->MLBC0,
+		      enable_6pin << MLBC0_MLBPEN_BIT |
+		      mlb_clock << MLBC0_MLBCLK_SHIFT |
+		      MLBC0_FCNT_VAL(FRAMES_PER_SUBBUFF) << MLBC0_FCNT_SHIFT |
+		      true << MLBC0_MLBEN_BIT);
+
+	/* activate all HBI channels */
+	DIMCB_IoWrite(&g.dim2->HCMR0, 0xFFFFFFFF);
+	DIMCB_IoWrite(&g.dim2->HCMR1, 0xFFFFFFFF);
+
+	/* enable HBI */
+	DIMCB_IoWrite(&g.dim2->HCTL, bit_mask(HCTL_EN_BIT));
+
+	/* configure DMA */
+	DIMCB_IoWrite(&g.dim2->ACTL,
+		      ACTL_DMA_MODE_VAL_DMA_MODE_1 << ACTL_DMA_MODE_BIT |
+		      true << ACTL_SCE_BIT);
+
+#if 0
+	DIMCB_IoWrite(&g.dim2->MIEN,
+		      bit_mask(MIEN_CTX_BREAK_BIT) |
+		      bit_mask(MIEN_CTX_PE_BIT) |
+		      bit_mask(MIEN_CTX_DONE_BIT) |
+		      bit_mask(MIEN_CRX_BREAK_BIT) |
+		      bit_mask(MIEN_CRX_PE_BIT) |
+		      bit_mask(MIEN_CRX_DONE_BIT) |
+		      bit_mask(MIEN_ATX_BREAK_BIT) |
+		      bit_mask(MIEN_ATX_PE_BIT) |
+		      bit_mask(MIEN_ATX_DONE_BIT) |
+		      bit_mask(MIEN_ARX_BREAK_BIT) |
+		      bit_mask(MIEN_ARX_PE_BIT) |
+		      bit_mask(MIEN_ARX_DONE_BIT));
+#endif
+}
+
+static bool dim2_is_mlb_locked(void)
+{
+	u32 const mask0 = bit_mask(MLBC0_MLBLK_BIT);
+	u32 const mask1 = bit_mask(MLBC1_CLKMERR_BIT) |
+			  bit_mask(MLBC1_LOCKERR_BIT);
+	u32 const c1 = DIMCB_IoRead(&g.dim2->MLBC1);
+	u32 const nda_mask = (u32)MLBC1_NDA_MASK << MLBC1_NDA_SHIFT;
+
+	DIMCB_IoWrite(&g.dim2->MLBC1, c1 & nda_mask);
+	return (DIMCB_IoRead(&g.dim2->MLBC1) & mask1) == 0 &&
+	       (DIMCB_IoRead(&g.dim2->MLBC0) & mask0) != 0;
+}
+
+
+/* -------------------------------------------------------------------------- */
+/* channel help routines */
+
+static inline bool service_channel(u8 ch_addr, u8 idx)
+{
+	u8 const shift = idx * 16;
+	u32 const adt1 = dim2_read_ctr(ADT + ch_addr, 1);
+
+	if (((adt1 >> (ADT1_DNE_BIT + shift)) & 1) == 0)
+		return false;
+
+	{
+		u32 mask[4] = { 0, 0, 0, 0 };
+		u32 adt_w[4] = { 0, 0, 0, 0 };
+
+		mask[1] =
+			bit_mask(ADT1_DNE_BIT + shift) |
+			bit_mask(ADT1_ERR_BIT + shift) |
+			bit_mask(ADT1_RDY_BIT + shift);
+		dim2_write_ctr_mask(ADT + ch_addr, mask, adt_w);
+	}
+
+	/* clear channel status bit */
+	DIMCB_IoWrite(&g.dim2->ACSR0, bit_mask(ch_addr));
+
+	return true;
+}
+
+
+/* -------------------------------------------------------------------------- */
+/* channel init routines */
+
+static void isoc_init(struct dim_channel *ch, u8 ch_addr, u16 packet_length)
+{
+	state_init(&ch->state);
+
+	ch->addr = ch_addr;
+
+	ch->packet_length = packet_length;
+	ch->bytes_per_frame = 0;
+	ch->done_sw_buffers_number = 0;
+}
+
+static void sync_init(struct dim_channel *ch, u8 ch_addr, u16 bytes_per_frame)
+{
+	state_init(&ch->state);
+
+	ch->addr = ch_addr;
+
+	ch->packet_length = 0;
+	ch->bytes_per_frame = bytes_per_frame;
+	ch->done_sw_buffers_number = 0;
+}
+
+static void channel_init(struct dim_channel *ch, u8 ch_addr)
+{
+	state_init(&ch->state);
+
+	ch->addr = ch_addr;
+
+	ch->packet_length = 0;
+	ch->bytes_per_frame = 0;
+	ch->done_sw_buffers_number = 0;
+}
+
+/* returns true if channel interrupt state is cleared */
+static bool channel_service_interrupt(struct dim_channel *ch)
+{
+	struct int_ch_state *const state = &ch->state;
+
+	if (!service_channel(ch->addr, state->idx2))
+		return false;
+
+	state->idx2 ^= 1;
+	state->request_counter++;
+	return true;
+}
+
+static bool channel_start(struct dim_channel *ch, u32 buf_addr, u16 buf_size)
+{
+	struct int_ch_state *const state = &ch->state;
+
+	if (buf_size <= 0)
+		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE, "Bad buffer size");
+
+	if (ch->packet_length == 0 && ch->bytes_per_frame == 0 &&
+	    buf_size != norm_ctrl_async_buffer_size(buf_size))
+		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
+				    "Bad control/async buffer size");
+
+	if (ch->packet_length &&
+	    buf_size != norm_isoc_buffer_size(buf_size, ch->packet_length))
+		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
+				    "Bad isochronous buffer size");
+
+	if (ch->bytes_per_frame &&
+	    buf_size != norm_sync_buffer_size(buf_size, ch->bytes_per_frame))
+		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
+				    "Bad synchronous buffer size");
+
+	if (state->level >= 2u)
+		return dim_on_error(DIM_ERR_OVERFLOW, "Channel overflow");
+
+	++state->level;
+
+	if (ch->packet_length || ch->bytes_per_frame)
+		dim2_start_isoc_sync(ch->addr, state->idx1, buf_addr, buf_size);
+	else
+		dim2_start_ctrl_async(ch->addr, state->idx1, buf_addr, buf_size);
+	state->idx1 ^= 1;
+
+	return true;
+}
+
+static u8 channel_service(struct dim_channel *ch)
+{
+	struct int_ch_state *const state = &ch->state;
+
+	if (state->service_counter != state->request_counter) {
+		state->service_counter++;
+		if (state->level == 0)
+			return DIM_ERR_UNDERFLOW;
+
+		--state->level;
+		ch->done_sw_buffers_number++;
+	}
+
+	return DIM_NO_ERROR;
+}
+
+static bool channel_detach_buffers(struct dim_channel *ch, u16 buffers_number)
+{
+	if (buffers_number > ch->done_sw_buffers_number)
+		return dim_on_error(DIM_ERR_UNDERFLOW, "Channel underflow");
+
+	ch->done_sw_buffers_number -= buffers_number;
+	return true;
+}
+
+
+/* -------------------------------------------------------------------------- */
+/* API */
+
+u8 DIM_Startup(void *dim_base_address, u32 mlb_clock)
+{
+	g.dim_is_initialized = false;
+
+	if (!dim_base_address)
+		return DIM_INIT_ERR_DIM_ADDR;
+
+	/* MediaLB clock: 0 - 256 fs, 1 - 512 fs, 2 - 1024 fs, 3 - 2048 fs */
+	/* MediaLB clock: 4 - 3072 fs, 5 - 4096 fs, 6 - 6144 fs, 7 - 8192 fs */
+	if (mlb_clock >= 8)
+		return DIM_INIT_ERR_MLB_CLOCK;
+
+	g.dim2 = dim_base_address;
+	g.dbr_map[0] = g.dbr_map[1] = 0;
+
+	dim2_initialize(mlb_clock >= 3, mlb_clock);
+
+	g.dim_is_initialized = true;
+
+	return DIM_NO_ERROR;
+}
+
+void DIM_Shutdown(void)
+{
+	g.dim_is_initialized = false;
+	dim2_cleanup();
+}
+
+bool DIM_GetLockState(void)
+{
+	return dim2_is_mlb_locked();
+}
+
+static u8 init_ctrl_async(struct dim_channel *ch, u8 type, u8 is_tx,
+			  u16 ch_address, u16 hw_buffer_size)
+{
+	if (!g.dim_is_initialized || !ch)
+		return DIM_ERR_DRIVER_NOT_INITIALIZED;
+
+	if (!check_channel_address(ch_address))
+		return DIM_INIT_ERR_CHANNEL_ADDRESS;
+
+	ch->dbr_size = hw_buffer_size;
+	ch->dbr_addr = alloc_dbr(ch->dbr_size);
+	if (ch->dbr_addr >= DBR_SIZE)
+		return DIM_INIT_ERR_OUT_OF_MEMORY;
+
+	channel_init(ch, ch_address / 2);
+
+	dim2_configure_channel(ch->addr, type, is_tx,
+			       ch->dbr_addr, ch->dbr_size, 0, false);
+
+	return DIM_NO_ERROR;
+}
+
+u16 DIM_NormCtrlAsyncBufferSize(u16 buf_size)
+{
+	return norm_ctrl_async_buffer_size(buf_size);
+}
+
+/**
+ * Retrieves maximal possible correct buffer size for isochronous data type
+ * conform to given packet length and not bigger than given buffer size.
+ *
+ * Returns non-zero correct buffer size or zero by error.
+ */
+u16 DIM_NormIsocBufferSize(u16 buf_size, u16 packet_length)
+{
+	if (!check_packet_length(packet_length))
+		return 0;
+
+	return norm_isoc_buffer_size(buf_size, packet_length);
+}
+
+/**
+ * Retrieves maximal possible correct buffer size for synchronous data type
+ * conform to given bytes per frame and not bigger than given buffer size.
+ *
+ * Returns non-zero correct buffer size or zero by error.
+ */
+u16 DIM_NormSyncBufferSize(u16 buf_size, u16 bytes_per_frame)
+{
+	if (!check_bytes_per_frame(bytes_per_frame))
+		return 0;
+
+	return norm_sync_buffer_size(buf_size, bytes_per_frame);
+}
+
+u8 DIM_InitControl(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		   u16 max_buffer_size)
+{
+	return init_ctrl_async(ch, CAT_CT_VAL_CONTROL, is_tx, ch_address,
+			       max_buffer_size * 2);
+}
+
+u8 DIM_InitAsync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		 u16 max_buffer_size)
+{
+	return init_ctrl_async(ch, CAT_CT_VAL_ASYNC, is_tx, ch_address,
+			       max_buffer_size * 2);
+}
+
+u8 DIM_InitIsoc(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		u16 packet_length)
+{
+	if (!g.dim_is_initialized || !ch)
+		return DIM_ERR_DRIVER_NOT_INITIALIZED;
+
+	if (!check_channel_address(ch_address))
+		return DIM_INIT_ERR_CHANNEL_ADDRESS;
+
+	if (!check_packet_length(packet_length))
+		return DIM_ERR_BAD_CONFIG;
+
+	ch->dbr_size = packet_length * ISOC_DBR_FACTOR;
+	ch->dbr_addr = alloc_dbr(ch->dbr_size);
+	if (ch->dbr_addr >= DBR_SIZE)
+		return DIM_INIT_ERR_OUT_OF_MEMORY;
+
+	isoc_init(ch, ch_address / 2, packet_length);
+
+	dim2_configure_channel(ch->addr, CAT_CT_VAL_ISOC, is_tx, ch->dbr_addr,
+			       ch->dbr_size, packet_length, false);
+
+	return DIM_NO_ERROR;
+}
+
+u8 DIM_InitSync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		u16 bytes_per_frame)
+{
+	if (!g.dim_is_initialized || !ch)
+		return DIM_ERR_DRIVER_NOT_INITIALIZED;
+
+	if (!check_channel_address(ch_address))
+		return DIM_INIT_ERR_CHANNEL_ADDRESS;
+
+	if (!check_bytes_per_frame(bytes_per_frame))
+		return DIM_ERR_BAD_CONFIG;
+
+	ch->dbr_size = bytes_per_frame * SYNC_DBR_FACTOR;
+	ch->dbr_addr = alloc_dbr(ch->dbr_size);
+	if (ch->dbr_addr >= DBR_SIZE)
+		return DIM_INIT_ERR_OUT_OF_MEMORY;
+
+	sync_init(ch, ch_address / 2, bytes_per_frame);
+
+	dim2_configure_channel(ch->addr, CAT_CT_VAL_SYNC, is_tx,
+			       ch->dbr_addr, ch->dbr_size, 0, true);
+
+	return DIM_NO_ERROR;
+}
+
+u8 DIM_DestroyChannel(struct dim_channel *ch)
+{
+	if (!g.dim_is_initialized || !ch)
+		return DIM_ERR_DRIVER_NOT_INITIALIZED;
+
+	dim2_clear_channel(ch->addr);
+	if (ch->dbr_addr < DBR_SIZE)
+		free_dbr(ch->dbr_addr, ch->dbr_size);
+	ch->dbr_addr = DBR_SIZE;
+
+	return DIM_NO_ERROR;
+}
+
+void DIM_ServiceIrq(struct dim_channel *const *channels)
+{
+	bool state_changed;
+
+	if (!g.dim_is_initialized) {
+		dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED,
+			     "DIM is not initialized");
+		return;
+	}
+
+	if (!channels) {
+		dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED, "Bad channels");
+		return;
+	}
+
+	/*
+	 * Use while-loop and a flag to make sure the age is changed back at least once,
+	 * otherwise the interrupt may never come if CPU generates interrupt on changing age.
+	 *
+	 * This cycle runs not more than number of channels, because service_interrupts
+	 * routine doesn't start the channel again.
+	 */
+	do {
+		struct dim_channel *const *ch = channels;
+
+		state_changed = false;
+
+		while (*ch) {
+			state_changed |= channel_service_interrupt(*ch);
+			++ch;
+		}
+	} while (state_changed);
+
+	/* clear pending Interrupts */
+	DIMCB_IoWrite(&g.dim2->MS0, 0);
+	DIMCB_IoWrite(&g.dim2->MS1, 0);
+}
+
+u8 DIM_ServiceChannel(struct dim_channel *ch)
+{
+	if (!g.dim_is_initialized || !ch)
+		return DIM_ERR_DRIVER_NOT_INITIALIZED;
+
+	return channel_service(ch);
+}
+
+struct dim_ch_state_t *DIM_GetChannelState(struct dim_channel *ch,
+		struct dim_ch_state_t *state_ptr)
+{
+	if (!ch || !state_ptr)
+		return 0;
+
+	state_ptr->ready = ch->state.level < 2;
+	state_ptr->done_buffers = ch->done_sw_buffers_number;
+
+	return state_ptr;
+}
+
+bool DIM_EnqueueBuffer(struct dim_channel *ch, u32 buffer_addr, u16 buffer_size)
+{
+	if (!ch)
+		return dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED, "Bad channel");
+
+	return channel_start(ch, buffer_addr, buffer_size);
+}
+
+bool DIM_DetachBuffers(struct dim_channel *ch, u16 buffers_number)
+{
+	if (!ch)
+		return dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED, "Bad channel");
+
+	return channel_detach_buffers(ch, buffers_number);
+}
+
+u32 DIM_ReadRegister(u8 register_index)
+{
+	return DIMCB_IoRead((u32 *)g.dim2 + register_index);
+}
diff --git a/drivers/staging/most/hdm-dim2/dim2_hal.h b/drivers/staging/most/hdm-dim2/dim2_hal.h
new file mode 100644
index 000000000000..d88b5a0e3244
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_hal.h
@@ -0,0 +1,124 @@
+/*
+ * dim2_hal.h - DIM2 HAL interface
+ * (MediaLB, Device Interface Macro IP, OS62420)
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#ifndef _DIM2_HAL_H
+#define _DIM2_HAL_H
+
+#include <linux/types.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * The values below are specified in the hardware specification.
+ * So, they should not be changed until the hardware specification changes.
+ */
+enum mlb_clk_speed {
+	CLK_256FS = 0,
+	CLK_512FS = 1,
+	CLK_1024FS = 2,
+	CLK_2048FS = 3,
+	CLK_3072FS = 4,
+	CLK_4096FS = 5,
+	CLK_6144FS = 6,
+	CLK_8192FS = 7,
+};
+
+struct dim_ch_state_t {
+	bool ready; /* Shows readiness to enqueue next buffer */
+	u16 done_buffers; /* Number of completed buffers */
+};
+
+typedef int atomic_counter_t;
+
+struct int_ch_state {
+	/* changed only in interrupt context */
+	volatile atomic_counter_t request_counter;
+
+	/* changed only in task context */
+	volatile atomic_counter_t service_counter;
+
+	u8 idx1;
+	u8 idx2;
+	u8 level; /* [0..2], buffering level */
+};
+
+struct dim_channel {
+	struct int_ch_state state;
+	u8 addr;
+	u16 dbr_addr;
+	u16 dbr_size;
+	u16 packet_length; /*< Isochronous packet length in bytes. */
+	u16 bytes_per_frame; /*< Synchronous bytes per frame. */
+	u16 done_sw_buffers_number; /*< Done software buffers number. */
+};
+
+
+u8 DIM_Startup(void *dim_base_address, u32 mlb_clock);
+
+void DIM_Shutdown(void);
+
+bool DIM_GetLockState(void);
+
+u16 DIM_NormCtrlAsyncBufferSize(u16 buf_size);
+
+u16 DIM_NormIsocBufferSize(u16 buf_size, u16 packet_length);
+
+u16 DIM_NormSyncBufferSize(u16 buf_size, u16 bytes_per_frame);
+
+u8 DIM_InitControl(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		   u16 max_buffer_size);
+
+u8 DIM_InitAsync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		 u16 max_buffer_size);
+
+u8 DIM_InitIsoc(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		u16 packet_length);
+
+u8 DIM_InitSync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
+		u16 bytes_per_frame);
+
+u8 DIM_DestroyChannel(struct dim_channel *ch);
+
+void DIM_ServiceIrq(struct dim_channel *const *channels);
+
+u8 DIM_ServiceChannel(struct dim_channel *ch);
+
+struct dim_ch_state_t *DIM_GetChannelState(struct dim_channel *ch,
+		struct dim_ch_state_t *dim_ch_state_ptr);
+
+bool DIM_EnqueueBuffer(struct dim_channel *ch, u32 buffer_addr,
+		       u16 buffer_size);
+
+bool DIM_DetachBuffers(struct dim_channel *ch, u16 buffers_number);
+
+u32 DIM_ReadRegister(u8 register_index);
+
+
+extern u32 DIMCB_IoRead(u32 *ptr32);
+
+extern void DIMCB_IoWrite(u32 *ptr32, u32 value);
+
+extern void DIMCB_OnError(u8 error_id, const char *error_message);
+
+extern void DIMCB_OnFail(const char *filename, int linenum);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _DIM2_HAL_H */
diff --git a/drivers/staging/most/hdm-dim2/dim2_hdm.c b/drivers/staging/most/hdm-dim2/dim2_hdm.c
new file mode 100644
index 000000000000..6a5a3a2775f3
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_hdm.c
@@ -0,0 +1,964 @@
+/*
+ * dim2_hdm.c - MediaLB DIM2 Hardware Dependent Module
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/dma-mapping.h>
+#include <linux/sched.h>
+#include <linux/kthread.h>
+
+#include <mostcore.h>
+#include <networking.h>
+#include "dim2_hal.h"
+#include "dim2_hdm.h"
+#include "dim2_errors.h"
+#include "dim2_sysfs.h"
+
+#define DMA_CHANNELS (32 - 1)  /* channel 0 is a system channel */
+
+#define MAX_BUFFERS_PACKET      32
+#define MAX_BUFFERS_STREAMING   32
+#define MAX_BUF_SIZE_PACKET     2048
+#define MAX_BUF_SIZE_STREAMING  (8*1024)
+
+/* command line parameter to select clock speed */
+static char *clock_speed;
+module_param(clock_speed, charp, 0);
+MODULE_PARM_DESC(clock_speed, "MediaLB Clock Speed");
+
+/*
+ * #############################################################################
+ *
+ * The define below activates an utility function used by HAL-simu
+ * for calling DIM interrupt handler.
+ * It is used only for TEST PURPOSE and shall be commented before release.
+ *
+ * #############################################################################
+ */
+/* #define ENABLE_HDM_TEST */
+
+static DEFINE_SPINLOCK(dim_lock);
+
+static void dim2_tasklet_fn(unsigned long data);
+static DECLARE_TASKLET(dim2_tasklet, dim2_tasklet_fn, 0);
+
+/**
+ * struct hdm_channel - private structure to keep channel specific data
+ * @is_initialized: identifier to know whether the channel is initialized
+ * @ch: HAL specific channel data
+ * @pending_list: list to keep MBO's before starting transfer
+ * @started_list: list to keep MBO's after starting transfer
+ * @direction: channel direction (TX or RX)
+ * @data_type: channel data type
+ */
+struct hdm_channel {
+	char name[sizeof "caNNN"];
+	bool is_initialized;
+	struct dim_channel ch;
+	struct list_head pending_list;	/* before DIM_EnqueueBuffer() */
+	struct list_head started_list;	/* after DIM_EnqueueBuffer() */
+	enum most_channel_direction direction;
+	enum most_channel_data_type data_type;
+};
+
+/**
+ * struct dim2_hdm - private structure to keep interface specific data
+ * @hch: an array of channel specific data
+ * @most_iface: most interface structure
+ * @capabilities: an array of channel capability data
+ * @io_base: I/O register base address
+ * @irq_ahb0: dim2 AHB0 irq number
+ * @clk_speed: user selectable (through command line parameter) clock speed
+ * @netinfo_task: thread to deliver network status
+ * @netinfo_waitq: waitq for the thread to sleep
+ * @deliver_netinfo: to identify whether network status received
+ * @mac_addrs: INIC mac address
+ * @link_state: network link state
+ * @atx_idx: index of async tx channel
+ */
+struct dim2_hdm {
+	struct hdm_channel hch[DMA_CHANNELS];
+	struct most_channel_capability capabilities[DMA_CHANNELS];
+	struct most_interface most_iface;
+	char name[16 + sizeof "dim2-"];
+	void *io_base;
+	unsigned int irq_ahb0;
+	int clk_speed;
+	struct task_struct *netinfo_task;
+	wait_queue_head_t netinfo_waitq;
+	int deliver_netinfo;
+	unsigned char mac_addrs[6];
+	unsigned char link_state;
+	int atx_idx;
+	struct medialb_bus bus;
+};
+
+#define iface_to_hdm(iface) container_of(iface, struct dim2_hdm, most_iface)
+
+/* Macro to identify a network status message */
+#define PACKET_IS_NET_INFO(p)  \
+	(((p)[1] == 0x18) && ((p)[2] == 0x05) && ((p)[3] == 0x0C) && \
+	 ((p)[13] == 0x3C) && ((p)[14] == 0x00) && ((p)[15] == 0x0A))
+
+#if defined(ENABLE_HDM_TEST)
+static struct dim2_hdm *test_dev;
+#endif
+
+bool dim2_sysfs_get_state_cb(void)
+{
+	bool state;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dim_lock, flags);
+	state = DIM_GetLockState();
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	return state;
+}
+
+/**
+ * DIMCB_IoRead - callback from HAL to read an I/O register
+ * @ptr32: register address
+ */
+u32 DIMCB_IoRead(u32 *ptr32)
+{
+	return __raw_readl(ptr32);
+}
+
+/**
+ * DIMCB_IoWrite - callback from HAL to write value to an I/O register
+ * @ptr32: register address
+ * @value: value to write
+ */
+void DIMCB_IoWrite(u32 *ptr32, u32 value)
+{
+	__raw_writel(value, ptr32);
+}
+
+/**
+ * DIMCB_OnError - callback from HAL to report miscommunication between
+ * HDM and HAL
+ * @error_id: Error ID
+ * @error_message: Error message. Some text in a free format
+ */
+void DIMCB_OnError(u8 error_id, const char *error_message)
+{
+	pr_err("DIMCB_OnError: error_id - %d, error_message - %s\n", error_id,
+	       error_message);
+}
+
+/**
+ * DIMCB_OnFail - callback from HAL to report unrecoverable errors
+ * @filename: Source file where the error happened
+ * @linenum: Line number of the file where the error happened
+ */
+void DIMCB_OnFail(const char *filename, int linenum)
+{
+	pr_err("DIMCB_OnFail: file - %s, line no. - %d\n", filename, linenum);
+}
+
+/**
+ * startup_dim - initialize the dim2 interface
+ * @pdev: platform device
+ *
+ * Get the value of command line parameter "clock_speed" if given or use the
+ * default value, enable the clock and PLL, and initialize the dim2 interface.
+ */
+static int startup_dim(struct platform_device *pdev)
+{
+	struct dim2_hdm *dev = platform_get_drvdata(pdev);
+	struct dim2_platform_data *pdata = pdev->dev.platform_data;
+	u8 hal_ret;
+
+	dev->clk_speed = -1;
+
+	if (clock_speed) {
+		if (!strcmp(clock_speed, "256fs"))
+			dev->clk_speed = CLK_256FS;
+		else if (!strcmp(clock_speed, "512fs"))
+			dev->clk_speed = CLK_512FS;
+		else if (!strcmp(clock_speed, "1024fs"))
+			dev->clk_speed = CLK_1024FS;
+		else if (!strcmp(clock_speed, "2048fs"))
+			dev->clk_speed = CLK_2048FS;
+		else if (!strcmp(clock_speed, "3072fs"))
+			dev->clk_speed = CLK_3072FS;
+		else if (!strcmp(clock_speed, "4096fs"))
+			dev->clk_speed = CLK_4096FS;
+		else if (!strcmp(clock_speed, "6144fs"))
+			dev->clk_speed = CLK_6144FS;
+		else if (!strcmp(clock_speed, "8192fs"))
+			dev->clk_speed = CLK_8192FS;
+	}
+
+	if (dev->clk_speed == -1) {
+		pr_info("Bad or missing clock speed parameter,"
+			" using default value: 3072fs\n");
+		dev->clk_speed = CLK_3072FS;
+	} else
+		pr_info("Selected clock speed: %s\n", clock_speed);
+
+	if (pdata && pdata->init) {
+		int ret = pdata->init(pdata, dev->io_base, dev->clk_speed);
+
+		if (ret)
+			return ret;
+	}
+
+	hal_ret = DIM_Startup(dev->io_base, dev->clk_speed);
+	if (hal_ret != DIM_NO_ERROR) {
+		pr_err("DIM_Startup failed: %d\n", hal_ret);
+		if (pdata && pdata->destroy)
+			pdata->destroy(pdata);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+/**
+ * try_start_dim_transfer - try to transfer a buffer on a channel
+ * @hdm_ch: channel specific data
+ *
+ * Transfer a buffer from pending_list if the channel is ready
+ */
+static int try_start_dim_transfer(struct hdm_channel *hdm_ch)
+{
+	u16 buf_size;
+	struct list_head *head = &hdm_ch->pending_list;
+	struct mbo *mbo;
+	unsigned long flags;
+	struct dim_ch_state_t st;
+
+	BUG_ON(hdm_ch == 0);
+	BUG_ON(!hdm_ch->is_initialized);
+
+	spin_lock_irqsave(&dim_lock, flags);
+	if (list_empty(head)) {
+		spin_unlock_irqrestore(&dim_lock, flags);
+		return -EAGAIN;
+	}
+
+	if (!DIM_GetChannelState(&hdm_ch->ch, &st)->ready) {
+		spin_unlock_irqrestore(&dim_lock, flags);
+		return -EAGAIN;
+	}
+
+	mbo = list_entry(head->next, struct mbo, list);
+	buf_size = mbo->buffer_length;
+
+	BUG_ON(mbo->bus_address == 0);
+	if (!DIM_EnqueueBuffer(&hdm_ch->ch, mbo->bus_address, buf_size)) {
+		list_del(head->next);
+		spin_unlock_irqrestore(&dim_lock, flags);
+		mbo->processed_length = 0;
+		mbo->status = MBO_E_INVAL;
+		mbo->complete(mbo);
+		return -EFAULT;
+	}
+
+	list_move_tail(head->next, &hdm_ch->started_list);
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	return 0;
+}
+
+/**
+ * deliver_netinfo_thread - thread to deliver network status to mostcore
+ * @data: private data
+ *
+ * Wait for network status and deliver it to mostcore once it is received
+ */
+static int deliver_netinfo_thread(void *data)
+{
+	struct dim2_hdm *dev = (struct dim2_hdm *)data;
+
+	while (!kthread_should_stop()) {
+		wait_event_interruptible(dev->netinfo_waitq,
+					 dev->deliver_netinfo ||
+					 kthread_should_stop());
+
+		if (dev->deliver_netinfo) {
+			dev->deliver_netinfo--;
+			most_deliver_netinfo(&dev->most_iface, dev->link_state,
+					     dev->mac_addrs);
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * retrieve_netinfo - retrieve network status from received buffer
+ * @dev: private data
+ * @mbo: received MBO
+ *
+ * Parse the message in buffer and get node address, link state, MAC address.
+ * Wake up a thread to deliver this status to mostcore
+ */
+static void retrieve_netinfo(struct dim2_hdm *dev, struct mbo *mbo)
+{
+	u8 *data = mbo->virt_address;
+	u8 *mac = dev->mac_addrs;
+
+	pr_info("Node Address: 0x%03x\n", (u16)data[16] << 8 | data[17]);
+	dev->link_state = data[18];
+	pr_info("NIState: %d\n", dev->link_state);
+	memcpy(mac, data + 19, 6);
+	pr_info("MAC address: %02X:%02X:%02X:%02X:%02X:%02X\n",
+		mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+	dev->deliver_netinfo++;
+	wake_up_interruptible(&dev->netinfo_waitq);
+}
+
+/**
+ * service_done_flag - handle completed buffers
+ * @dev: private data
+ * @ch_idx: channel index
+ *
+ * Return back the completed buffers to mostcore, using completion callback
+ */
+static void service_done_flag(struct dim2_hdm *dev, int ch_idx)
+{
+	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
+	struct dim_ch_state_t st;
+	struct list_head *head;
+	struct mbo *mbo;
+	int done_buffers;
+	unsigned long flags;
+	u8 *data;
+
+	BUG_ON(hdm_ch == 0);
+	BUG_ON(!hdm_ch->is_initialized);
+
+	spin_lock_irqsave(&dim_lock, flags);
+
+	done_buffers = DIM_GetChannelState(&hdm_ch->ch, &st)->done_buffers;
+	if (!done_buffers) {
+		spin_unlock_irqrestore(&dim_lock, flags);
+		return;
+	}
+
+	if (!DIM_DetachBuffers(&hdm_ch->ch, done_buffers)) {
+		spin_unlock_irqrestore(&dim_lock, flags);
+		return;
+	}
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	head = &hdm_ch->started_list;
+
+	while (done_buffers) {
+		spin_lock_irqsave(&dim_lock, flags);
+		if (list_empty(head)) {
+			spin_unlock_irqrestore(&dim_lock, flags);
+			pr_crit("hard error: started_mbo list is empty "
+				"whereas DIM2 has sent buffers\n");
+			break;
+		}
+
+		mbo = list_entry(head->next, struct mbo, list);
+		list_del(head->next);
+		spin_unlock_irqrestore(&dim_lock, flags);
+
+		data = mbo->virt_address;
+
+		if (hdm_ch->data_type == MOST_CH_ASYNC &&
+		    hdm_ch->direction == MOST_CH_RX &&
+		    PACKET_IS_NET_INFO(data)) {
+
+			retrieve_netinfo(dev, mbo);
+
+			spin_lock_irqsave(&dim_lock, flags);
+			list_add_tail(&mbo->list, &hdm_ch->pending_list);
+			spin_unlock_irqrestore(&dim_lock, flags);
+		} else {
+			if (hdm_ch->data_type == MOST_CH_CONTROL ||
+			    hdm_ch->data_type == MOST_CH_ASYNC) {
+
+				u32 const data_size =
+					(u32)data[0] * 256 + data[1] + 2;
+
+				mbo->processed_length =
+					min(data_size, (u32)mbo->buffer_length);
+			} else {
+				mbo->processed_length = mbo->buffer_length;
+			}
+			mbo->status = MBO_SUCCESS;
+			mbo->complete(mbo);
+		}
+
+		done_buffers--;
+	}
+}
+
+static struct dim_channel **get_active_channels(struct dim2_hdm *dev,
+		struct dim_channel **buffer)
+{
+	int idx = 0;
+	int ch_idx;
+
+	for (ch_idx = 0; ch_idx < DMA_CHANNELS; ch_idx++) {
+		if (dev->hch[ch_idx].is_initialized)
+			buffer[idx++] = &dev->hch[ch_idx].ch;
+	}
+	buffer[idx++] = 0;
+
+	return buffer;
+}
+
+/**
+ * dim2_tasklet_fn - tasklet function
+ * @data: private data
+ *
+ * Service each initialized channel, if needed
+ */
+static void dim2_tasklet_fn(unsigned long data)
+{
+	struct dim2_hdm *dev = (struct dim2_hdm *)data;
+	unsigned long flags;
+	int ch_idx;
+
+	for (ch_idx = 0; ch_idx < DMA_CHANNELS; ch_idx++) {
+		if (!dev->hch[ch_idx].is_initialized)
+			continue;
+
+		spin_lock_irqsave(&dim_lock, flags);
+		DIM_ServiceChannel(&(dev->hch[ch_idx].ch));
+		spin_unlock_irqrestore(&dim_lock, flags);
+
+		service_done_flag(dev, ch_idx);
+		while (!try_start_dim_transfer(dev->hch + ch_idx))
+			continue;
+	}
+}
+
+/**
+ * dim2_ahb_isr - interrupt service routine
+ * @irq: irq number
+ * @_dev: private data
+ *
+ * Acknowledge the interrupt and schedule a tasklet to service channels.
+ * Return IRQ_HANDLED.
+ */
+static irqreturn_t dim2_ahb_isr(int irq, void *_dev)
+{
+	struct dim2_hdm *dev = (struct dim2_hdm *)_dev;
+	struct dim_channel *buffer[DMA_CHANNELS + 1];
+	unsigned long flags;
+
+	spin_lock_irqsave(&dim_lock, flags);
+	DIM_ServiceIrq(get_active_channels(dev, buffer));
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+#if !defined(ENABLE_HDM_TEST)
+	dim2_tasklet.data = (unsigned long)dev;
+	tasklet_schedule(&dim2_tasklet);
+#else
+	dim2_tasklet_fn((unsigned long)dev);
+#endif
+	return IRQ_HANDLED;
+}
+
+#if defined(ENABLE_HDM_TEST)
+
+/*
+ * Utility function used by HAL-simu for calling DIM interrupt handler.
+ * It is used only for TEST PURPOSE.
+ */
+void raise_dim_interrupt(void)
+{
+	(void)dim2_ahb_isr(0, test_dev);
+}
+#endif
+
+/**
+ * complete_all_mbos - complete MBO's in a list
+ * @head: list head
+ *
+ * Delete all the entries in list and return back MBO's to mostcore using
+ * completion call back.
+ */
+static void complete_all_mbos(struct list_head *head)
+{
+	unsigned long flags;
+	struct mbo *mbo;
+
+	for (;;) {
+		spin_lock_irqsave(&dim_lock, flags);
+		if (list_empty(head)) {
+			spin_unlock_irqrestore(&dim_lock, flags);
+			break;
+		}
+
+		mbo = list_entry(head->next, struct mbo, list);
+		list_del(head->next);
+		spin_unlock_irqrestore(&dim_lock, flags);
+
+		mbo->processed_length = 0;
+		mbo->status = MBO_E_CLOSE;
+		mbo->complete(mbo);
+	}
+}
+
+/**
+ * configure_channel - initialize a channel
+ * @iface: interface the channel belongs to
+ * @channel: channel to be configured
+ * @channel_config: structure that holds the configuration information
+ *
+ * Receives configuration information from mostcore and initialize
+ * the corresponding channel. Return 0 on success, negative on failure.
+ */
+static int configure_channel(struct most_interface *most_iface, int ch_idx,
+			     struct most_channel_config *ccfg)
+{
+	struct dim2_hdm *dev = iface_to_hdm(most_iface);
+	bool const is_tx = ccfg->direction == MOST_CH_TX;
+	u16 const sub_size = ccfg->subbuffer_size;
+	u16 const buf_size = ccfg->buffer_size;
+	u16 new_size;
+	unsigned long flags;
+	u8 hal_ret;
+	int const ch_addr = ch_idx * 2 + 2;
+	struct hdm_channel *const hdm_ch = dev->hch + ch_idx;
+
+	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);
+
+	if (hdm_ch->is_initialized)
+		return -EPERM;
+
+	switch (ccfg->data_type) {
+	case MOST_CH_CONTROL:
+		new_size = DIM_NormCtrlAsyncBufferSize(buf_size);
+		if (new_size == 0) {
+			pr_err("%s: too small buffer size\n", hdm_ch->name);
+			return -EINVAL;
+		}
+		ccfg->buffer_size = new_size;
+		if (new_size != buf_size)
+			pr_warn("%s: fixed buffer size (%d -> %d)\n",
+				hdm_ch->name, buf_size, new_size);
+		spin_lock_irqsave(&dim_lock, flags);
+		hal_ret = DIM_InitControl(&hdm_ch->ch, is_tx, ch_addr, buf_size);
+		break;
+	case MOST_CH_ASYNC:
+		new_size = DIM_NormCtrlAsyncBufferSize(buf_size);
+		if (new_size == 0) {
+			pr_err("%s: too small buffer size\n", hdm_ch->name);
+			return -EINVAL;
+		}
+		ccfg->buffer_size = new_size;
+		if (new_size != buf_size)
+			pr_warn("%s: fixed buffer size (%d -> %d)\n",
+				hdm_ch->name, buf_size, new_size);
+		spin_lock_irqsave(&dim_lock, flags);
+		hal_ret = DIM_InitAsync(&hdm_ch->ch, is_tx, ch_addr, buf_size);
+		break;
+	case MOST_CH_ISOC_AVP:
+		new_size = DIM_NormIsocBufferSize(buf_size, sub_size);
+		if (new_size == 0) {
+			pr_err("%s: invalid sub-buffer size or "
+			       "too small buffer size\n", hdm_ch->name);
+			return -EINVAL;
+		}
+		ccfg->buffer_size = new_size;
+		if (new_size != buf_size)
+			pr_warn("%s: fixed buffer size (%d -> %d)\n",
+				hdm_ch->name, buf_size, new_size);
+		spin_lock_irqsave(&dim_lock, flags);
+		hal_ret = DIM_InitIsoc(&hdm_ch->ch, is_tx, ch_addr, sub_size);
+		break;
+	case MOST_CH_SYNC:
+		new_size = DIM_NormSyncBufferSize(buf_size, sub_size);
+		if (new_size == 0) {
+			pr_err("%s: invalid sub-buffer size or "
+			       "too small buffer size\n", hdm_ch->name);
+			return -EINVAL;
+		}
+		ccfg->buffer_size = new_size;
+		if (new_size != buf_size)
+			pr_warn("%s: fixed buffer size (%d -> %d)\n",
+				hdm_ch->name, buf_size, new_size);
+		spin_lock_irqsave(&dim_lock, flags);
+		hal_ret = DIM_InitSync(&hdm_ch->ch, is_tx, ch_addr, sub_size);
+		break;
+	default:
+		pr_err("%s: configure failed, bad channel type: %d\n",
+		       hdm_ch->name, ccfg->data_type);
+		return -EINVAL;
+	}
+
+	if (hal_ret != DIM_NO_ERROR) {
+		spin_unlock_irqrestore(&dim_lock, flags);
+		pr_err("%s: configure failed (%d), type: %d, is_tx: %d\n",
+		       hdm_ch->name, hal_ret, ccfg->data_type, (int)is_tx);
+		return -ENODEV;
+	}
+
+	hdm_ch->data_type = ccfg->data_type;
+	hdm_ch->direction = ccfg->direction;
+	hdm_ch->is_initialized = true;
+
+	if (hdm_ch->data_type == MOST_CH_ASYNC &&
+	    hdm_ch->direction == MOST_CH_TX &&
+	    dev->atx_idx < 0)
+		dev->atx_idx = ch_idx;
+
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	return 0;
+}
+
+/**
+ * enqueue - enqueue a buffer for data transfer
+ * @iface: intended interface
+ * @channel: ID of the channel the buffer is intended for
+ * @mbo: pointer to the buffer object
+ *
+ * Push the buffer into pending_list and try to transfer one buffer from
+ * pending_list. Return 0 on success, negative on failure.
+ */
+static int enqueue(struct most_interface *most_iface, int ch_idx,
+		   struct mbo *mbo)
+{
+	struct dim2_hdm *dev = iface_to_hdm(most_iface);
+	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
+	unsigned long flags;
+
+	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);
+
+	if (!hdm_ch->is_initialized)
+		return -EPERM;
+
+	if (mbo->bus_address == 0)
+		return -EFAULT;
+
+	spin_lock_irqsave(&dim_lock, flags);
+	list_add_tail(&mbo->list, &hdm_ch->pending_list);
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	(void)try_start_dim_transfer(hdm_ch);
+
+	return 0;
+}
+
+/**
+ * request_netinfo - triggers retrieving of network info
+ * @iface: pointer to the interface
+ * @channel_id: corresponding channel ID
+ *
+ * Send a command to INIC which triggers retrieving of network info by means of
+ * "Message exchange over MDP/MEP". Return 0 on success, negative on failure.
+ */
+static void request_netinfo(struct most_interface *most_iface, int ch_idx)
+{
+	struct dim2_hdm *dev = iface_to_hdm(most_iface);
+	struct mbo *mbo;
+	u8 *data;
+
+	if (dev->atx_idx < 0) {
+		pr_err("Async Tx Not initialized\n");
+		return;
+	}
+
+	mbo = most_get_mbo(&dev->most_iface, dev->atx_idx);
+	if (!mbo)
+		return;
+
+	mbo->buffer_length = 5;
+
+	data = mbo->virt_address;
+
+	data[0] = 0x00; /* PML High byte */
+	data[1] = 0x03; /* PML Low byte */
+	data[2] = 0x02; /* PMHL */
+	data[3] = 0x08; /* FPH */
+	data[4] = 0x40; /* FMF (FIFO cmd msg - Triggers NAOverMDP) */
+
+	most_submit_mbo(mbo);
+}
+
+/**
+ * poison_channel - poison buffers of a channel
+ * @iface: pointer to the interface the channel to be poisoned belongs to
+ * @channel_id: corresponding channel ID
+ *
+ * Destroy a channel and complete all the buffers in both started_list &
+ * pending_list. Return 0 on success, negative on failure.
+ */
+static int poison_channel(struct most_interface *most_iface, int ch_idx)
+{
+	struct dim2_hdm *dev = iface_to_hdm(most_iface);
+	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
+	unsigned long flags;
+	u8 hal_ret;
+	int ret = 0;
+
+	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);
+
+	if (!hdm_ch->is_initialized)
+		return -EPERM;
+
+	spin_lock_irqsave(&dim_lock, flags);
+	hal_ret = DIM_DestroyChannel(&hdm_ch->ch);
+	hdm_ch->is_initialized = false;
+	if (ch_idx == dev->atx_idx)
+		dev->atx_idx = -1;
+	spin_unlock_irqrestore(&dim_lock, flags);
+	if (hal_ret != DIM_NO_ERROR) {
+		pr_err("HAL Failed to close channel %s\n", hdm_ch->name);
+		ret = -EFAULT;
+	}
+
+	complete_all_mbos(&hdm_ch->started_list);
+	complete_all_mbos(&hdm_ch->pending_list);
+
+	return ret;
+}
+
+/*
+ * dim2_probe - dim2 probe handler
+ * @pdev: platform device structure
+ *
+ * Register the dim2 interface with mostcore and initialize it.
+ * Return 0 on success, negative on failure.
+ */
+static int dim2_probe(struct platform_device *pdev)
+{
+	struct dim2_hdm *dev;
+	struct resource *res;
+	int ret, i;
+	struct kobject *kobj;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	dev->atx_idx = -1;
+
+	platform_set_drvdata(pdev, dev);
+#if defined(ENABLE_HDM_TEST)
+	test_dev = dev;
+#else
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		pr_err("no memory region defined\n");
+		ret = -ENOENT;
+		goto err_free_dev;
+	}
+
+	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+		pr_err("failed to request mem region\n");
+		ret = -EBUSY;
+		goto err_free_dev;
+	}
+
+	dev->io_base = ioremap(res->start, resource_size(res));
+	if (!dev->io_base) {
+		pr_err("failed to ioremap\n");
+		ret = -ENOMEM;
+		goto err_release_mem;
+	}
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0) {
+		pr_err("failed to get irq\n");
+		goto err_unmap_io;
+	}
+	dev->irq_ahb0 = ret;
+
+	ret = request_irq(dev->irq_ahb0, dim2_ahb_isr, 0, "mlb_ahb0", dev);
+	if (ret) {
+		pr_err("failed to request IRQ: %d, err: %d\n", dev->irq_ahb0, ret);
+		goto err_unmap_io;
+	}
+#endif
+	init_waitqueue_head(&dev->netinfo_waitq);
+	dev->deliver_netinfo = 0;
+	dev->netinfo_task = kthread_run(&deliver_netinfo_thread, (void *)dev,
+					"dim2_netinfo");
+	if (IS_ERR(dev->netinfo_task)) {
+		ret = PTR_ERR(dev->netinfo_task);
+		goto err_free_irq;
+	}
+
+	for (i = 0; i < DMA_CHANNELS; i++) {
+		struct most_channel_capability *cap = dev->capabilities + i;
+		struct hdm_channel *hdm_ch = dev->hch + i;
+
+		INIT_LIST_HEAD(&hdm_ch->pending_list);
+		INIT_LIST_HEAD(&hdm_ch->started_list);
+		hdm_ch->is_initialized = false;
+		snprintf(hdm_ch->name, sizeof(hdm_ch->name), "ca%d", i * 2 + 2);
+
+		cap->name_suffix = hdm_ch->name;
+		cap->direction = MOST_CH_RX | MOST_CH_TX;
+		cap->data_type = MOST_CH_CONTROL | MOST_CH_ASYNC |
+				 MOST_CH_ISOC_AVP | MOST_CH_SYNC;
+		cap->num_buffers_packet = MAX_BUFFERS_PACKET;
+		cap->buffer_size_packet = MAX_BUF_SIZE_PACKET;
+		cap->num_buffers_streaming = MAX_BUFFERS_STREAMING;
+		cap->buffer_size_streaming = MAX_BUF_SIZE_STREAMING;
+	}
+
+	{
+		const char *fmt;
+
+		if (sizeof(res->start) == sizeof(long long))
+			fmt = "dim2-%016llx";
+		else if (sizeof(res->start) == sizeof(long))
+			fmt = "dim2-%016lx";
+		else
+			fmt = "dim2-%016x";
+
+		snprintf(dev->name, sizeof(dev->name), fmt, res->start);
+	}
+
+	dev->most_iface.interface = ITYPE_MEDIALB_DIM2;
+	dev->most_iface.description = dev->name;
+	dev->most_iface.num_channels = DMA_CHANNELS;
+	dev->most_iface.channel_vector = dev->capabilities;
+	dev->most_iface.configure = configure_channel;
+	dev->most_iface.enqueue = enqueue;
+	dev->most_iface.poison_channel = poison_channel;
+	dev->most_iface.request_netinfo = request_netinfo;
+
+	kobj = most_register_interface(&dev->most_iface);
+	if (IS_ERR(kobj)) {
+		ret = PTR_ERR(kobj);
+		pr_err("failed to register MOST interface\n");
+		goto err_stop_thread;
+	}
+
+	ret = dim2_sysfs_probe(&dev->bus, kobj);
+	if (ret)
+		goto err_unreg_iface;
+
+	ret = startup_dim(pdev);
+	if (ret) {
+		pr_err("failed to initialize DIM2\n");
+		goto err_destroy_bus;
+	}
+
+	return 0;
+
+err_destroy_bus:
+	dim2_sysfs_destroy(&dev->bus);
+err_unreg_iface:
+	most_deregister_interface(&dev->most_iface);
+err_stop_thread:
+	kthread_stop(dev->netinfo_task);
+err_free_irq:
+#if !defined(ENABLE_HDM_TEST)
+	free_irq(dev->irq_ahb0, dev);
+err_unmap_io:
+	iounmap(dev->io_base);
+err_release_mem:
+	release_mem_region(res->start, resource_size(res));
+err_free_dev:
+#endif
+	kfree(dev);
+
+	return ret;
+}
+
+/**
+ * dim2_remove - dim2 remove handler
+ * @pdev: platform device structure
+ *
+ * Unregister the interface from mostcore
+ */
+static int dim2_remove(struct platform_device *pdev)
+{
+	struct dim2_hdm *dev = platform_get_drvdata(pdev);
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	struct dim2_platform_data *pdata = pdev->dev.platform_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dim_lock, flags);
+	DIM_Shutdown();
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	if (pdata && pdata->destroy)
+		pdata->destroy(pdata);
+
+	dim2_sysfs_destroy(&dev->bus);
+	most_deregister_interface(&dev->most_iface);
+	kthread_stop(dev->netinfo_task);
+#if !defined(ENABLE_HDM_TEST)
+	free_irq(dev->irq_ahb0, dev);
+	iounmap(dev->io_base);
+	release_mem_region(res->start, resource_size(res));
+#endif
+	kfree(dev);
+	platform_set_drvdata(pdev, NULL);
+
+	/*
+	 * break link to local platform_device_id struct
+	 * to prevent crash by unload platform device module
+	 */
+	pdev->id_entry = 0;
+
+	return 0;
+}
+
+static struct platform_device_id dim2_id[] = {
+	{ "medialb_dim2" },
+	{ }, /* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(platform, dim2_id);
+
+static struct platform_driver dim2_driver = {
+	.probe = dim2_probe,
+	.remove = dim2_remove,
+	.id_table = dim2_id,
+	.driver = {
+		.name = "hdm_dim2",
+		.owner = THIS_MODULE,
+	},
+};
+
+/**
+ * dim2_hdm_init - Driver Registration Routine
+ */
+static int __init dim2_hdm_init(void)
+{
+	pr_info("dim2_hdm_init()\n");
+	return platform_driver_register(&dim2_driver);
+}
+
+/**
+ * dim2_hdm_exit - Driver Cleanup Routine
+ **/
+static void __exit dim2_hdm_exit(void)
+{
+	pr_info("dim2_hdm_exit()\n");
+	platform_driver_unregister(&dim2_driver);
+}
+
+module_init(dim2_hdm_init);
+module_exit(dim2_hdm_exit);
+
+MODULE_AUTHOR("Jain Roy Ambi <JainRoy.Ambi@microchip.com>");
+MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
+MODULE_DESCRIPTION("MediaLB DIM2 Hardware Dependent Module");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/most/hdm-dim2/dim2_hdm.h b/drivers/staging/most/hdm-dim2/dim2_hdm.h
new file mode 100644
index 000000000000..6e6883232809
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_hdm.h
@@ -0,0 +1,26 @@
+/*
+ * dim2_hdm.h - MediaLB DIM2 HDM Header
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#ifndef DIM2_HDM_H
+#define	DIM2_HDM_H
+
+struct device;
+
+/* platform dependent data for dim2 interface */
+struct dim2_platform_data {
+	int (*init)(struct dim2_platform_data *pd, void *io_base, int clk_speed);
+	void (*destroy)(struct dim2_platform_data *pd);
+	void *priv;
+};
+
+#endif	/* DIM2_HDM_H */
diff --git a/drivers/staging/most/hdm-dim2/dim2_reg.h b/drivers/staging/most/hdm-dim2/dim2_reg.h
new file mode 100644
index 000000000000..476f66f4c566
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_reg.h
@@ -0,0 +1,176 @@
+/*
+ * dim2_reg.h - Definitions for registers of DIM2
+ * (MediaLB, Device Interface Macro IP, OS62420)
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#ifndef DIM2_OS62420_H
+#define	DIM2_OS62420_H
+
+#include <linux/types.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+
+struct dim2_regs {
+	/* 0x00 */ u32 MLBC0;
+	/* 0x01 */ u32 rsvd0[1];
+	/* 0x02 */ u32 MLBPC0;
+	/* 0x03 */ u32 MS0;
+	/* 0x04 */ u32 rsvd1[1];
+	/* 0x05 */ u32 MS1;
+	/* 0x06 */ u32 rsvd2[2];
+	/* 0x08 */ u32 MSS;
+	/* 0x09 */ u32 MSD;
+	/* 0x0A */ u32 rsvd3[1];
+	/* 0x0B */ u32 MIEN;
+	/* 0x0C */ u32 rsvd4[1];
+	/* 0x0D */ u32 MLBPC2;
+	/* 0x0E */ u32 MLBPC1;
+	/* 0x0F */ u32 MLBC1;
+	/* 0x10 */ u32 rsvd5[0x10];
+	/* 0x20 */ u32 HCTL;
+	/* 0x21 */ u32 rsvd6[1];
+	/* 0x22 */ u32 HCMR0;
+	/* 0x23 */ u32 HCMR1;
+	/* 0x24 */ u32 HCER0;
+	/* 0x25 */ u32 HCER1;
+	/* 0x26 */ u32 HCBR0;
+	/* 0x27 */ u32 HCBR1;
+	/* 0x28 */ u32 rsvd7[8];
+	/* 0x30 */ u32 MDAT0;
+	/* 0x31 */ u32 MDAT1;
+	/* 0x32 */ u32 MDAT2;
+	/* 0x33 */ u32 MDAT3;
+	/* 0x34 */ u32 MDWE0;
+	/* 0x35 */ u32 MDWE1;
+	/* 0x36 */ u32 MDWE2;
+	/* 0x37 */ u32 MDWE3;
+	/* 0x38 */ u32 MCTL;
+	/* 0x39 */ u32 MADR;
+	/* 0x3A */ u32 rsvd8[0xB6];
+	/* 0xF0 */ u32 ACTL;
+	/* 0xF1 */ u32 rsvd9[3];
+	/* 0xF4 */ u32 ACSR0;
+	/* 0xF5 */ u32 ACSR1;
+	/* 0xF6 */ u32 ACMR0;
+	/* 0xF7 */ u32 ACMR1;
+};
+
+
+#define DIM2_MASK(n)  (~((~(u32)0)<<(n)))
+
+enum {
+	MLBC0_MLBLK_BIT = 7,
+
+	MLBC0_MLBPEN_BIT = 5,
+
+	MLBC0_MLBCLK_SHIFT = 2,
+	MLBC0_MLBCLK_VAL_256FS = 0,
+	MLBC0_MLBCLK_VAL_512FS = 1,
+	MLBC0_MLBCLK_VAL_1024FS = 2,
+	MLBC0_MLBCLK_VAL_2048FS = 3,
+
+	MLBC0_FCNT_SHIFT = 15,
+	MLBC0_FCNT_MASK = 7,
+	MLBC0_FCNT_VAL_1FPSB = 0,
+	MLBC0_FCNT_VAL_2FPSB = 1,
+	MLBC0_FCNT_VAL_4FPSB = 2,
+	MLBC0_FCNT_VAL_8FPSB = 3,
+	MLBC0_FCNT_VAL_16FPSB = 4,
+	MLBC0_FCNT_VAL_32FPSB = 5,
+	MLBC0_FCNT_VAL_64FPSB = 6,
+
+	MLBC0_MLBEN_BIT = 0,
+
+	MIEN_CTX_BREAK_BIT = 29,
+	MIEN_CTX_PE_BIT = 28,
+	MIEN_CTX_DONE_BIT = 27,
+
+	MIEN_CRX_BREAK_BIT = 26,
+	MIEN_CRX_PE_BIT = 25,
+	MIEN_CRX_DONE_BIT = 24,
+
+	MIEN_ATX_BREAK_BIT = 22,
+	MIEN_ATX_PE_BIT = 21,
+	MIEN_ATX_DONE_BIT = 20,
+
+	MIEN_ARX_BREAK_BIT = 19,
+	MIEN_ARX_PE_BIT = 18,
+	MIEN_ARX_DONE_BIT = 17,
+
+	MIEN_SYNC_PE_BIT = 16,
+
+	MIEN_ISOC_BUFO_BIT = 1,
+	MIEN_ISOC_PE_BIT = 0,
+
+	MLBC1_NDA_SHIFT = 8,
+	MLBC1_NDA_MASK = 0xFF,
+
+	MLBC1_CLKMERR_BIT = 7,
+	MLBC1_LOCKERR_BIT = 6,
+
+	ACTL_DMA_MODE_BIT = 2,
+	ACTL_DMA_MODE_VAL_DMA_MODE_0 = 0,
+	ACTL_DMA_MODE_VAL_DMA_MODE_1 = 1,
+	ACTL_SCE_BIT = 0,
+
+	HCTL_EN_BIT = 15
+};
+
+enum {
+	CDT1_BS_ISOC_SHIFT = 0,
+	CDT1_BS_ISOC_MASK = DIM2_MASK(9),
+
+	CDT3_BD_SHIFT = 0,
+	CDT3_BD_MASK = DIM2_MASK(12),
+	CDT3_BD_ISOC_MASK = DIM2_MASK(13),
+	CDT3_BA_SHIFT = 16,
+
+	ADT0_CE_BIT = 15,
+	ADT0_LE_BIT = 14,
+	ADT0_PG_BIT = 13,
+
+	ADT1_RDY_BIT = 15,
+	ADT1_DNE_BIT = 14,
+	ADT1_ERR_BIT = 13,
+	ADT1_PS_BIT = 12,
+	ADT1_MEP_BIT = 11,
+	ADT1_BD_SHIFT = 0,
+	ADT1_CTRL_ASYNC_BD_MASK = DIM2_MASK(11),
+	ADT1_ISOC_SYNC_BD_MASK = DIM2_MASK(13),
+
+	CAT_MFE_BIT = 14,
+
+	CAT_MT_BIT = 13,
+
+	CAT_RNW_BIT = 12,
+
+	CAT_CE_BIT = 11,
+
+	CAT_CT_SHIFT = 8,
+	CAT_CT_VAL_SYNC = 0,
+	CAT_CT_VAL_CONTROL = 1,
+	CAT_CT_VAL_ASYNC = 2,
+	CAT_CT_VAL_ISOC = 3,
+
+	CAT_CL_SHIFT = 0,
+	CAT_CL_MASK = DIM2_MASK(6)
+};
+
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* DIM2_OS62420_H */
diff --git a/drivers/staging/most/hdm-dim2/dim2_sysfs.c b/drivers/staging/most/hdm-dim2/dim2_sysfs.c
new file mode 100644
index 000000000000..8e331a286fc3
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_sysfs.c
@@ -0,0 +1,116 @@
+/*
+ * dim2_sysfs.c - MediaLB sysfs information
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+/* Author: Andrey Shvetsov <andrey.shvetsov@k2l.de> */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include "dim2_sysfs.h"
+
+struct bus_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct medialb_bus *bus, char *buf);
+	ssize_t (*store)(struct medialb_bus *bus, const char *buf, size_t count);
+};
+
+static ssize_t state_show(struct medialb_bus *bus, char *buf)
+{
+	bool state = dim2_sysfs_get_state_cb();
+
+	return sprintf(buf, "%s\n", state ? "locked" : "");
+}
+
+static struct bus_attr state_attr = __ATTR_RO(state);
+
+static struct attribute *bus_default_attrs[] = {
+	&state_attr.attr,
+	NULL,
+};
+
+static struct attribute_group bus_attr_group = {
+	.attrs = bus_default_attrs,
+};
+
+static void bus_kobj_release(struct kobject *kobj)
+{
+}
+
+static ssize_t bus_kobj_attr_show(struct kobject *kobj, struct attribute *attr,
+				  char *buf)
+{
+	struct medialb_bus *bus =
+		container_of(kobj, struct medialb_bus, kobj_group);
+	struct bus_attr *xattr = container_of(attr, struct bus_attr, attr);
+
+	if (!xattr->show)
+		return -EIO;
+
+	return xattr->show(bus, buf);
+}
+
+static ssize_t bus_kobj_attr_store(struct kobject *kobj, struct attribute *attr,
+				   const char *buf, size_t count)
+{
+	ssize_t ret;
+	struct medialb_bus *bus =
+		container_of(kobj, struct medialb_bus, kobj_group);
+	struct bus_attr *xattr = container_of(attr, struct bus_attr, attr);
+
+	if (!xattr->store)
+		return -EIO;
+
+	ret = xattr->store(bus, buf, count);
+	return ret;
+}
+
+static struct sysfs_ops const bus_kobj_sysfs_ops = {
+	.show = bus_kobj_attr_show,
+	.store = bus_kobj_attr_store,
+};
+
+static struct kobj_type bus_ktype = {
+	.release = bus_kobj_release,
+	.sysfs_ops = &bus_kobj_sysfs_ops,
+};
+
+int dim2_sysfs_probe(struct medialb_bus *bus, struct kobject *parent_kobj)
+{
+	int err;
+
+	kobject_init(&bus->kobj_group, &bus_ktype);
+	err = kobject_add(&bus->kobj_group, parent_kobj, "bus");
+	if (err) {
+		pr_err("kobject_add() failed: %d\n", err);
+		goto err_kobject_add;
+	}
+
+	err = sysfs_create_group(&bus->kobj_group, &bus_attr_group);
+	if (err) {
+		pr_err("sysfs_create_group() failed: %d\n", err);
+		goto err_create_group;
+	}
+
+	return 0;
+
+err_create_group:
+	kobject_put(&bus->kobj_group);
+
+err_kobject_add:
+	return err;
+}
+
+void dim2_sysfs_destroy(struct medialb_bus *bus)
+{
+	kobject_put(&bus->kobj_group);
+}
diff --git a/drivers/staging/most/hdm-dim2/dim2_sysfs.h b/drivers/staging/most/hdm-dim2/dim2_sysfs.h
new file mode 100644
index 000000000000..e719691035b0
--- /dev/null
+++ b/drivers/staging/most/hdm-dim2/dim2_sysfs.h
@@ -0,0 +1,39 @@
+/*
+ * dim2_sysfs.h - MediaLB sysfs information
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+/* Author: Andrey Shvetsov <andrey.shvetsov@k2l.de> */
+
+#ifndef DIM2_SYSFS_H
+#define	DIM2_SYSFS_H
+
+
+#include <linux/kobject.h>
+
+
+struct medialb_bus {
+	struct kobject kobj_group;
+};
+
+struct dim2_hdm;
+
+int dim2_sysfs_probe(struct medialb_bus *bus, struct kobject *parent_kobj);
+void dim2_sysfs_destroy(struct medialb_bus *bus);
+
+/*
+ * callback,
+ * must deliver MediaLB state as true if locked or false if unlocked
+ */
+bool dim2_sysfs_get_state_cb(void);
+
+
+#endif	/* DIM2_SYSFS_H */