drivers/staging/msm/mddihost.c - linux - Git at Google

 /* Copyright (c) 2008-2009, Code Aurora Forum. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
  * only version 2 as published by the Free Software Foundation.
  *
  * 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.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/mm.h>
 #include <linux/fb.h>
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/device.h>
 #include <linux/dma-mapping.h>

 #include "msm_fb.h"
 #include "mddihost.h"
 #include "mddihosti.h"

 #include <linux/clk.h>
 #include <mach/clk.h>

 struct semaphore mddi_host_mutex;

 struct clk *mddi_io_clk;
 static boolean mddi_host_powered = FALSE;
 static boolean mddi_host_initialized = FALSE;
 extern uint32 *mddi_reg_read_value_ptr;

 mddi_lcd_func_type mddi_lcd;

 extern mddi_client_capability_type mddi_client_capability_pkt;

 #ifdef FEATURE_MDDI_HITACHI
 extern void mddi_hitachi_window_adjust(uint16 x1,
 				       uint16 x2, uint16 y1, uint16 y2);
 #endif

 extern void mddi_toshiba_lcd_init(void);

 #ifdef FEATURE_MDDI_S6D0142
 extern void mddi_s6d0142_lcd_init(void);
 extern void mddi_s6d0142_window_adjust(uint16 x1,
 				       uint16 x2,
 				       uint16 y1,
 				       uint16 y2,
 				       mddi_llist_done_cb_type done_cb);
 #endif

 void mddi_init(void)
 {
 	if (mddi_host_initialized)
 		return;

 	mddi_host_initialized = TRUE;

 	sema_init(&mddi_host_mutex, 1);

 	if (!mddi_host_powered) {
 		down(&mddi_host_mutex);
 		mddi_host_init(MDDI_HOST_PRIM);
 		mddi_host_powered = TRUE;
 		up(&mddi_host_mutex);
 		mdelay(10);
 	}
 }

 int mddi_host_register_read(uint32 reg_addr,
      uint32 *reg_value_ptr, boolean wait, mddi_host_type host) {
 	mddi_linked_list_type *curr_llist_ptr;
 	mddi_register_access_packet_type *regacc_pkt_ptr;
 	uint16 curr_llist_idx;
 	int ret = 0;

 	if (in_interrupt())
 		MDDI_MSG_CRIT("Called from ISR context\n");

 	if (!mddi_host_powered) {
 		MDDI_MSG_ERR("MDDI powered down!\n");
 		mddi_init();
 	}

 	down(&mddi_host_mutex);

 	mddi_reg_read_value_ptr = reg_value_ptr;
 	curr_llist_idx = mddi_get_reg_read_llist_item(host, TRUE);
 	if (curr_llist_idx == UNASSIGNED_INDEX) {
 		up(&mddi_host_mutex);

 		/* need to change this to some sort of wait */
 		MDDI_MSG_ERR("Attempting to queue up more than 1 reg read\n");
 		return -EINVAL;
 	}

 	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
 	curr_llist_ptr->link_controller_flags = 0x11;
 	curr_llist_ptr->packet_header_count = 14;
 	curr_llist_ptr->packet_data_count = 0;

 	curr_llist_ptr->next_packet_pointer = NULL;
 	curr_llist_ptr->packet_data_pointer = NULL;
 	curr_llist_ptr->reserved = 0;

 	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

 	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count;
 	regacc_pkt_ptr->packet_type = 146;	/* register access packet */
 	regacc_pkt_ptr->bClient_ID = 0;
 	regacc_pkt_ptr->read_write_info = 0x8001;
 	regacc_pkt_ptr->register_address = reg_addr;

 	/* now adjust pointers */
 	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, wait,
 				   NULL, host);
 	/* need to check if we can write the pointer or not */

 	up(&mddi_host_mutex);

 	if (wait) {
 		int wait_ret;

 		mddi_linked_list_notify_type *llist_notify_ptr;
 		llist_notify_ptr = &llist_extern_notify[host][curr_llist_idx];
 		wait_ret = wait_for_completion_timeout(
 					&(llist_notify_ptr->done_comp), 5 * HZ);

 		if (wait_ret <= 0)
 			ret = -EBUSY;

 		if (wait_ret < 0)
 			printk(KERN_ERR "%s: failed to wait for completion!\n",
 				__func__);
 		else if (!wait_ret)
 			printk(KERN_ERR "%s: Timed out waiting!\n", __func__);
 	}

 	MDDI_MSG_DEBUG("Reg Read value=0x%x\n", *reg_value_ptr);

 	return ret;
 }				/* mddi_host_register_read */

 int mddi_host_register_write(uint32 reg_addr,
      uint32 reg_val, enum mddi_data_packet_size_type packet_size,
      boolean wait, mddi_llist_done_cb_type done_cb, mddi_host_type host) {
 	mddi_linked_list_type *curr_llist_ptr;
 	mddi_linked_list_type *curr_llist_dma_ptr;
 	mddi_register_access_packet_type *regacc_pkt_ptr;
 	uint16 curr_llist_idx;
 	int ret = 0;

 	if (in_interrupt())
 		MDDI_MSG_CRIT("Called from ISR context\n");

 	if (!mddi_host_powered) {
 		MDDI_MSG_ERR("MDDI powered down!\n");
 		mddi_init();
 	}

 	down(&mddi_host_mutex);

 	curr_llist_idx = mddi_get_next_free_llist_item(host, TRUE);
 	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
 	curr_llist_dma_ptr = &llist_dma_extern[host][curr_llist_idx];

 	curr_llist_ptr->link_controller_flags = 1;
 	curr_llist_ptr->packet_header_count = 14;
 	curr_llist_ptr->packet_data_count = 4;

 	curr_llist_ptr->next_packet_pointer = NULL;
 	curr_llist_ptr->reserved = 0;

 	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

 	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count +
 					(uint16)packet_size;
 	regacc_pkt_ptr->packet_type = 146;	/* register access packet */
 	regacc_pkt_ptr->bClient_ID = 0;
 	regacc_pkt_ptr->read_write_info = 0x0001;
 	regacc_pkt_ptr->register_address = reg_addr;
 	regacc_pkt_ptr->register_data_list = reg_val;

 	MDDI_MSG_DEBUG("Reg Access write reg=0x%x, value=0x%x\n",
 		       regacc_pkt_ptr->register_address,
 		       regacc_pkt_ptr->register_data_list);

 	regacc_pkt_ptr = &curr_llist_dma_ptr->packet_header.register_pkt;
 	curr_llist_ptr->packet_data_pointer =
 	    (void *)(&regacc_pkt_ptr->register_data_list);

 	/* now adjust pointers */
 	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, wait,
 				   done_cb, host);

 	up(&mddi_host_mutex);

 	if (wait) {
 		int wait_ret;

 		mddi_linked_list_notify_type *llist_notify_ptr;
 		llist_notify_ptr = &llist_extern_notify[host][curr_llist_idx];
 		wait_ret = wait_for_completion_timeout(
 					&(llist_notify_ptr->done_comp), 5 * HZ);

 		if (wait_ret <= 0)
 			ret = -EBUSY;

 		if (wait_ret < 0)
 			printk(KERN_ERR "%s: failed to wait for completion!\n",
 				__func__);
 		else if (!wait_ret)
 			printk(KERN_ERR "%s: Timed out waiting!\n", __func__);
 	}

 	return ret;
 }				/* mddi_host_register_write */

 boolean mddi_host_register_read_int
     (uint32 reg_addr, uint32 *reg_value_ptr, mddi_host_type host) {
 	mddi_linked_list_type *curr_llist_ptr;
 	mddi_register_access_packet_type *regacc_pkt_ptr;
 	uint16 curr_llist_idx;

 	if (!in_interrupt())
 		MDDI_MSG_CRIT("Called from TASK context\n");

 	if (!mddi_host_powered) {
 		MDDI_MSG_ERR("MDDI powered down!\n");
 		return FALSE;
 	}

 	if (down_trylock(&mddi_host_mutex) != 0)
 		return FALSE;

 	mddi_reg_read_value_ptr = reg_value_ptr;
 	curr_llist_idx = mddi_get_reg_read_llist_item(host, FALSE);
 	if (curr_llist_idx == UNASSIGNED_INDEX) {
 		up(&mddi_host_mutex);
 		return FALSE;
 	}

 	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
 	curr_llist_ptr->link_controller_flags = 0x11;
 	curr_llist_ptr->packet_header_count = 14;
 	curr_llist_ptr->packet_data_count = 0;

 	curr_llist_ptr->next_packet_pointer = NULL;
 	curr_llist_ptr->packet_data_pointer = NULL;
 	curr_llist_ptr->reserved = 0;

 	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

 	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count;
 	regacc_pkt_ptr->packet_type = 146;	/* register access packet */
 	regacc_pkt_ptr->bClient_ID = 0;
 	regacc_pkt_ptr->read_write_info = 0x8001;
 	regacc_pkt_ptr->register_address = reg_addr;

 	/* now adjust pointers */
 	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, FALSE,
 				   NULL, host);
 	/* need to check if we can write the pointer or not */

 	up(&mddi_host_mutex);

 	return TRUE;

 }				/* mddi_host_register_read */

 boolean mddi_host_register_write_int
     (uint32 reg_addr,
      uint32 reg_val, mddi_llist_done_cb_type done_cb, mddi_host_type host) {
 	mddi_linked_list_type *curr_llist_ptr;
 	mddi_linked_list_type *curr_llist_dma_ptr;
 	mddi_register_access_packet_type *regacc_pkt_ptr;
 	uint16 curr_llist_idx;

 	if (!in_interrupt())
 		MDDI_MSG_CRIT("Called from TASK context\n");

 	if (!mddi_host_powered) {
 		MDDI_MSG_ERR("MDDI powered down!\n");
 		return FALSE;
 	}

 	if (down_trylock(&mddi_host_mutex) != 0)
 		return FALSE;

 	curr_llist_idx = mddi_get_next_free_llist_item(host, FALSE);
 	if (curr_llist_idx == UNASSIGNED_INDEX) {
 		up(&mddi_host_mutex);
 		return FALSE;
 	}

 	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
 	curr_llist_dma_ptr = &llist_dma_extern[host][curr_llist_idx];

 	curr_llist_ptr->link_controller_flags = 1;
 	curr_llist_ptr->packet_header_count = 14;
 	curr_llist_ptr->packet_data_count = 4;

 	curr_llist_ptr->next_packet_pointer = NULL;
 	curr_llist_ptr->reserved = 0;

 	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

 	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count + 4;
 	regacc_pkt_ptr->packet_type = 146;	/* register access packet */
 	regacc_pkt_ptr->bClient_ID = 0;
 	regacc_pkt_ptr->read_write_info = 0x0001;
 	regacc_pkt_ptr->register_address = reg_addr;
 	regacc_pkt_ptr->register_data_list = reg_val;

 	regacc_pkt_ptr = &curr_llist_dma_ptr->packet_header.register_pkt;
 	curr_llist_ptr->packet_data_pointer =
 	    (void *)(&(regacc_pkt_ptr->register_data_list));

 	/* now adjust pointers */
 	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, FALSE,
 				   done_cb, host);
 	up(&mddi_host_mutex);

 	return TRUE;

 }				/* mddi_host_register_write */

 void mddi_wait(uint16 time_ms)
 {
 	mdelay(time_ms);
 }

 void mddi_client_lcd_vsync_detected(boolean detected)
 {
 	if (mddi_lcd.vsync_detected)
 		(*mddi_lcd.vsync_detected) (detected);
 }

 /* extended version of function includes done callback */
 void mddi_window_adjust_ext(struct msm_fb_data_type *mfd,
 			    uint16 x1,
 			    uint16 x2,
 			    uint16 y1,
 			    uint16 y2, mddi_llist_done_cb_type done_cb)
 {
 #ifdef FEATURE_MDDI_HITACHI
 	if (mfd->panel.id == HITACHI)
 		mddi_hitachi_window_adjust(x1, x2, y1, y2);
 #elif defined(FEATURE_MDDI_S6D0142)
 	if (mfd->panel.id == MDDI_LCD_S6D0142)
 		mddi_s6d0142_window_adjust(x1, x2, y1, y2, done_cb);
 #else
 	/* Do nothing then... except avoid lint/compiler warnings */
 	(void)x1;
 	(void)x2;
 	(void)y1;
 	(void)y2;
 	(void)done_cb;
 #endif
 }

 void mddi_window_adjust(struct msm_fb_data_type *mfd,
 			uint16 x1, uint16 x2, uint16 y1, uint16 y2)
 {
 	mddi_window_adjust_ext(mfd, x1, x2, y1, y2, NULL);
 }
	/* Copyright (c) 2008-2009, Code Aurora Forum. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 and
	* only version 2 as published by the Free Software Foundation.
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	* 02110-1301, USA.
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/delay.h>
	#include <linux/mm.h>
	#include <linux/fb.h>
	#include <linux/init.h>
	#include <linux/ioport.h>
	#include <linux/device.h>
	#include <linux/dma-mapping.h>

	#include "msm_fb.h"
	#include "mddihost.h"
	#include "mddihosti.h"

	#include <linux/clk.h>
	#include <mach/clk.h>

	struct semaphore mddi_host_mutex;

	struct clk *mddi_io_clk;
	static boolean mddi_host_powered = FALSE;
	static boolean mddi_host_initialized = FALSE;
	extern uint32 *mddi_reg_read_value_ptr;

	mddi_lcd_func_type mddi_lcd;

	extern mddi_client_capability_type mddi_client_capability_pkt;

	#ifdef FEATURE_MDDI_HITACHI
	extern void mddi_hitachi_window_adjust(uint16 x1,
	uint16 x2, uint16 y1, uint16 y2);
	#endif

	extern void mddi_toshiba_lcd_init(void);

	#ifdef FEATURE_MDDI_S6D0142
	extern void mddi_s6d0142_lcd_init(void);
	extern void mddi_s6d0142_window_adjust(uint16 x1,
	uint16 x2,
	uint16 y1,
	uint16 y2,
	mddi_llist_done_cb_type done_cb);
	#endif

	void mddi_init(void)
	{
	if (mddi_host_initialized)
	return;

	mddi_host_initialized = TRUE;

	sema_init(&mddi_host_mutex, 1);

	if (!mddi_host_powered) {
	down(&mddi_host_mutex);
	mddi_host_init(MDDI_HOST_PRIM);
	mddi_host_powered = TRUE;
	up(&mddi_host_mutex);
	mdelay(10);
	}
	}

	int mddi_host_register_read(uint32 reg_addr,
	uint32 *reg_value_ptr, boolean wait, mddi_host_type host) {
	mddi_linked_list_type *curr_llist_ptr;
	mddi_register_access_packet_type *regacc_pkt_ptr;
	uint16 curr_llist_idx;
	int ret = 0;

	if (in_interrupt())
	MDDI_MSG_CRIT("Called from ISR context\n");

	if (!mddi_host_powered) {
	MDDI_MSG_ERR("MDDI powered down!\n");
	mddi_init();
	}

	down(&mddi_host_mutex);

	mddi_reg_read_value_ptr = reg_value_ptr;
	curr_llist_idx = mddi_get_reg_read_llist_item(host, TRUE);
	if (curr_llist_idx == UNASSIGNED_INDEX) {
	up(&mddi_host_mutex);

	/* need to change this to some sort of wait */
	MDDI_MSG_ERR("Attempting to queue up more than 1 reg read\n");
	return -EINVAL;
	}

	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
	curr_llist_ptr->link_controller_flags = 0x11;
	curr_llist_ptr->packet_header_count = 14;
	curr_llist_ptr->packet_data_count = 0;

	curr_llist_ptr->next_packet_pointer = NULL;
	curr_llist_ptr->packet_data_pointer = NULL;
	curr_llist_ptr->reserved = 0;

	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count;
	regacc_pkt_ptr->packet_type = 146; /* register access packet */
	regacc_pkt_ptr->bClient_ID = 0;
	regacc_pkt_ptr->read_write_info = 0x8001;
	regacc_pkt_ptr->register_address = reg_addr;

	/* now adjust pointers */
	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, wait,
	NULL, host);
	/* need to check if we can write the pointer or not */

	up(&mddi_host_mutex);

	if (wait) {
	int wait_ret;

	mddi_linked_list_notify_type *llist_notify_ptr;
	llist_notify_ptr = &llist_extern_notify[host][curr_llist_idx];
	wait_ret = wait_for_completion_timeout(
	&(llist_notify_ptr->done_comp), 5 * HZ);

	if (wait_ret <= 0)
	ret = -EBUSY;

	if (wait_ret < 0)
	printk(KERN_ERR "%s: failed to wait for completion!\n",
	__func__);
	else if (!wait_ret)
	printk(KERN_ERR "%s: Timed out waiting!\n", __func__);
	}

	MDDI_MSG_DEBUG("Reg Read value=0x%x\n", *reg_value_ptr);

	return ret;
	} /* mddi_host_register_read */

	int mddi_host_register_write(uint32 reg_addr,
	uint32 reg_val, enum mddi_data_packet_size_type packet_size,
	boolean wait, mddi_llist_done_cb_type done_cb, mddi_host_type host) {
	mddi_linked_list_type *curr_llist_ptr;
	mddi_linked_list_type *curr_llist_dma_ptr;
	mddi_register_access_packet_type *regacc_pkt_ptr;
	uint16 curr_llist_idx;
	int ret = 0;

	if (in_interrupt())
	MDDI_MSG_CRIT("Called from ISR context\n");

	if (!mddi_host_powered) {
	MDDI_MSG_ERR("MDDI powered down!\n");
	mddi_init();
	}

	down(&mddi_host_mutex);

	curr_llist_idx = mddi_get_next_free_llist_item(host, TRUE);
	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
	curr_llist_dma_ptr = &llist_dma_extern[host][curr_llist_idx];

	curr_llist_ptr->link_controller_flags = 1;
	curr_llist_ptr->packet_header_count = 14;
	curr_llist_ptr->packet_data_count = 4;

	curr_llist_ptr->next_packet_pointer = NULL;
	curr_llist_ptr->reserved = 0;

	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count +
	(uint16)packet_size;
	regacc_pkt_ptr->packet_type = 146; /* register access packet */
	regacc_pkt_ptr->bClient_ID = 0;
	regacc_pkt_ptr->read_write_info = 0x0001;
	regacc_pkt_ptr->register_address = reg_addr;
	regacc_pkt_ptr->register_data_list = reg_val;

	MDDI_MSG_DEBUG("Reg Access write reg=0x%x, value=0x%x\n",
	regacc_pkt_ptr->register_address,
	regacc_pkt_ptr->register_data_list);

	regacc_pkt_ptr = &curr_llist_dma_ptr->packet_header.register_pkt;
	curr_llist_ptr->packet_data_pointer =
	(void *)(&regacc_pkt_ptr->register_data_list);

	/* now adjust pointers */
	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, wait,
	done_cb, host);

	up(&mddi_host_mutex);

	if (wait) {
	int wait_ret;

	mddi_linked_list_notify_type *llist_notify_ptr;
	llist_notify_ptr = &llist_extern_notify[host][curr_llist_idx];
	wait_ret = wait_for_completion_timeout(
	&(llist_notify_ptr->done_comp), 5 * HZ);

	if (wait_ret <= 0)
	ret = -EBUSY;

	if (wait_ret < 0)
	printk(KERN_ERR "%s: failed to wait for completion!\n",
	__func__);
	else if (!wait_ret)
	printk(KERN_ERR "%s: Timed out waiting!\n", __func__);
	}

	return ret;
	} /* mddi_host_register_write */

	boolean mddi_host_register_read_int
	(uint32 reg_addr, uint32 *reg_value_ptr, mddi_host_type host) {
	mddi_linked_list_type *curr_llist_ptr;
	mddi_register_access_packet_type *regacc_pkt_ptr;
	uint16 curr_llist_idx;

	if (!in_interrupt())
	MDDI_MSG_CRIT("Called from TASK context\n");

	if (!mddi_host_powered) {
	MDDI_MSG_ERR("MDDI powered down!\n");
	return FALSE;
	}

	if (down_trylock(&mddi_host_mutex) != 0)
	return FALSE;

	mddi_reg_read_value_ptr = reg_value_ptr;
	curr_llist_idx = mddi_get_reg_read_llist_item(host, FALSE);
	if (curr_llist_idx == UNASSIGNED_INDEX) {
	up(&mddi_host_mutex);
	return FALSE;
	}

	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
	curr_llist_ptr->link_controller_flags = 0x11;
	curr_llist_ptr->packet_header_count = 14;
	curr_llist_ptr->packet_data_count = 0;

	curr_llist_ptr->next_packet_pointer = NULL;
	curr_llist_ptr->packet_data_pointer = NULL;
	curr_llist_ptr->reserved = 0;

	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count;
	regacc_pkt_ptr->packet_type = 146; /* register access packet */
	regacc_pkt_ptr->bClient_ID = 0;
	regacc_pkt_ptr->read_write_info = 0x8001;
	regacc_pkt_ptr->register_address = reg_addr;

	/* now adjust pointers */
	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, FALSE,
	NULL, host);
	/* need to check if we can write the pointer or not */

	up(&mddi_host_mutex);

	return TRUE;

	} /* mddi_host_register_read */

	boolean mddi_host_register_write_int
	(uint32 reg_addr,
	uint32 reg_val, mddi_llist_done_cb_type done_cb, mddi_host_type host) {
	mddi_linked_list_type *curr_llist_ptr;
	mddi_linked_list_type *curr_llist_dma_ptr;
	mddi_register_access_packet_type *regacc_pkt_ptr;
	uint16 curr_llist_idx;

	if (!in_interrupt())
	MDDI_MSG_CRIT("Called from TASK context\n");

	if (!mddi_host_powered) {
	MDDI_MSG_ERR("MDDI powered down!\n");
	return FALSE;
	}

	if (down_trylock(&mddi_host_mutex) != 0)
	return FALSE;

	curr_llist_idx = mddi_get_next_free_llist_item(host, FALSE);
	if (curr_llist_idx == UNASSIGNED_INDEX) {
	up(&mddi_host_mutex);
	return FALSE;
	}

	curr_llist_ptr = &llist_extern[host][curr_llist_idx];
	curr_llist_dma_ptr = &llist_dma_extern[host][curr_llist_idx];

	curr_llist_ptr->link_controller_flags = 1;
	curr_llist_ptr->packet_header_count = 14;
	curr_llist_ptr->packet_data_count = 4;

	curr_llist_ptr->next_packet_pointer = NULL;
	curr_llist_ptr->reserved = 0;

	regacc_pkt_ptr = &curr_llist_ptr->packet_header.register_pkt;

	regacc_pkt_ptr->packet_length = curr_llist_ptr->packet_header_count + 4;
	regacc_pkt_ptr->packet_type = 146; /* register access packet */
	regacc_pkt_ptr->bClient_ID = 0;
	regacc_pkt_ptr->read_write_info = 0x0001;
	regacc_pkt_ptr->register_address = reg_addr;
	regacc_pkt_ptr->register_data_list = reg_val;

	regacc_pkt_ptr = &curr_llist_dma_ptr->packet_header.register_pkt;
	curr_llist_ptr->packet_data_pointer =
	(void *)(&(regacc_pkt_ptr->register_data_list));

	/* now adjust pointers */
	mddi_queue_forward_packets(curr_llist_idx, curr_llist_idx, FALSE,
	done_cb, host);
	up(&mddi_host_mutex);

	return TRUE;

	} /* mddi_host_register_write */

	void mddi_wait(uint16 time_ms)
	{
	mdelay(time_ms);
	}

	void mddi_client_lcd_vsync_detected(boolean detected)
	{
	if (mddi_lcd.vsync_detected)
	(*mddi_lcd.vsync_detected) (detected);
	}

	/* extended version of function includes done callback */
	void mddi_window_adjust_ext(struct msm_fb_data_type *mfd,
	uint16 x1,
	uint16 x2,
	uint16 y1,
	uint16 y2, mddi_llist_done_cb_type done_cb)
	{
	#ifdef FEATURE_MDDI_HITACHI
	if (mfd->panel.id == HITACHI)
	mddi_hitachi_window_adjust(x1, x2, y1, y2);
	#elif defined(FEATURE_MDDI_S6D0142)
	if (mfd->panel.id == MDDI_LCD_S6D0142)
	mddi_s6d0142_window_adjust(x1, x2, y1, y2, done_cb);
	#else
	/* Do nothing then... except avoid lint/compiler warnings */
	(void)x1;
	(void)x2;
	(void)y1;
	(void)y2;
	(void)done_cb;
	#endif
	}

	void mddi_window_adjust(struct msm_fb_data_type *mfd,
	uint16 x1, uint16 x2, uint16 y1, uint16 y2)
	{
	mddi_window_adjust_ext(mfd, x1, x2, y1, y2, NULL);
	}