static int __devexit mpc52xx_lpbfifo_remove(struct platform_device *op)
{
	if (lpbfifo.dev != &op->dev)
		return 0;

	/* Put FIFO in reset */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);

	/* Release the bestcomm transmit task */
	free_irq(bcom_get_task_irq(lpbfifo.bcom_tx_task), &lpbfifo);
	bcom_gen_bd_tx_release(lpbfifo.bcom_tx_task);

	/* Release the bestcomm receive task */
	free_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task), &lpbfifo);
	bcom_gen_bd_rx_release(lpbfifo.bcom_rx_task);

	free_irq(lpbfifo.irq, &lpbfifo);
	iounmap(lpbfifo.regs);
	lpbfifo.regs = NULL;
	lpbfifo.dev = NULL;

	return 0;
}
static int __devexit mpc52xx_lpbfifo_remove(struct platform_device *op)
{
	if (lpbfifo.dev != &op->dev)
		return 0;

	
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);

	
	free_irq(bcom_get_task_irq(lpbfifo.bcom_tx_task), &lpbfifo);
	bcom_gen_bd_tx_release(lpbfifo.bcom_tx_task);
	
	
	free_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task), &lpbfifo);
	bcom_gen_bd_rx_release(lpbfifo.bcom_rx_task);

	free_irq(lpbfifo.irq, &lpbfifo);
	iounmap(lpbfifo.regs);
	lpbfifo.regs = NULL;
	lpbfifo.dev = NULL;

	return 0;
}
/**
 * mpc52xx_lpbfifo_kick - Trigger the next block of data to be transferred
 */
static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
{
	size_t transfer_size = req->size - req->pos;
	struct bcom_bd *bd;
	void __iomem *reg;
	u32 *data;
	int i;
	int bit_fields;
	int dma = !(req->flags & MPC52XX_LPBFIFO_FLAG_NO_DMA);
	int write = req->flags & MPC52XX_LPBFIFO_FLAG_WRITE;
	int poll_dma = req->flags & MPC52XX_LPBFIFO_FLAG_POLL_DMA;

	/* Set and clear the reset bits; is good practice in User Manual */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);

	/* set master enable bit */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000001);
	if (!dma) {
		/* While the FIFO can be setup for transfer sizes as large as
		 * 16M-1, the FIFO itself is only 512 bytes deep and it does
		 * not generate interrupts for FIFO full events (only transfer
		 * complete will raise an IRQ).  Therefore when not using
		 * Bestcomm to drive the FIFO it needs to either be polled, or
		 * transfers need to constrained to the size of the fifo.
		 *
		 * This driver restricts the size of the transfer
		 */
		if (transfer_size > 512)
			transfer_size = 512;

		/* Load the FIFO with data */
		if (write) {
			reg = lpbfifo.regs + LPBFIFO_REG_FIFO_DATA;
			data = req->data + req->pos;
			for (i = 0; i < transfer_size; i += 4)
				out_be32(reg, *data++);
		}

		/* Unmask both error and completion irqs */
		out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000301);
	} else {
		/* Choose the correct direction
		 *
		 * Configure the watermarks so DMA will always complete correctly.
		 * It may be worth experimenting with the ALARM value to see if
		 * there is a performance impacit.  However, if it is wrong there
		 * is a risk of DMA not transferring the last chunk of data
		 */
		if (write) {
			out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1e4);
			out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 7);
			lpbfifo.bcom_cur_task = lpbfifo.bcom_tx_task;
		} else {
			out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1ff);
			out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 0);
			lpbfifo.bcom_cur_task = lpbfifo.bcom_rx_task;

			if (poll_dma) {
				if (lpbfifo.dma_irqs_enabled) {
					disable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
					lpbfifo.dma_irqs_enabled = 0;
				}
			} else {
				if (!lpbfifo.dma_irqs_enabled) {
					enable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
					lpbfifo.dma_irqs_enabled = 1;
				}
			}
		}

		bd = bcom_prepare_next_buffer(lpbfifo.bcom_cur_task);
		bd->status = transfer_size;
		if (!write) {
			/*
			 * In the DMA read case, the DMA doesn't complete,
			 * possibly due to incorrect watermarks in the ALARM
			 * and CONTROL regs. For now instead of trying to
			 * determine the right watermarks that will make this
			 * work, just increase the number of bytes the FIFO is
			 * expecting.
			 *
			 * When submitting another operation, the FIFO will get
			 * reset, so the condition of the FIFO waiting for a
			 * non-existent 4 bytes will get cleared.
			 */
			transfer_size += 4; /* BLECH! */
		}
		bd->data[0] = req->data_phys + req->pos;
		bcom_submit_next_buffer(lpbfifo.bcom_cur_task, NULL);

		/* error irq & master enabled bit */
		bit_fields = 0x00000201;

		/* Unmask irqs */
		if (write && (!poll_dma))
			bit_fields |= 0x00000100; /* completion irq too */
		out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, bit_fields);
	}

	/* Set transfer size, width, chip select and READ mode */
	out_be32(lpbfifo.regs + LPBFIFO_REG_START_ADDRESS,
		 req->offset + req->pos);
	out_be32(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, transfer_size);

	bit_fields = req->cs << 24 | 0x000008;
	if (!write)
		bit_fields |= 0x010000; /* read mode */
	out_be32(lpbfifo.regs + LPBFIFO_REG_CONTROL, bit_fields);

	/* Kick it off */
	out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
	if (dma)
		bcom_enable(lpbfifo.bcom_cur_task);
}
static int __devinit mpc52xx_lpbfifo_probe(struct platform_device *op)
{
	struct resource res;
	int rc = -ENOMEM;

	if (lpbfifo.dev != NULL)
		return -ENOSPC;

	lpbfifo.irq = irq_of_parse_and_map(op->dev.of_node, 0);
	if (!lpbfifo.irq)
		return -ENODEV;

	if (of_address_to_resource(op->dev.of_node, 0, &res))
		return -ENODEV;
	lpbfifo.regs_phys = res.start;
	lpbfifo.regs = of_iomap(op->dev.of_node, 0);
	if (!lpbfifo.regs)
		return -ENOMEM;

	spin_lock_init(&lpbfifo.lock);

	/* Put FIFO into reset */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);

	/* Register the interrupt handler */
	rc = request_irq(lpbfifo.irq, mpc52xx_lpbfifo_irq, 0,
			 "mpc52xx-lpbfifo", &lpbfifo);
	if (rc)
		goto err_irq;

	/* Request the Bestcomm receive (fifo --> memory) task and IRQ */
	lpbfifo.bcom_rx_task =
		bcom_gen_bd_rx_init(2, res.start + LPBFIFO_REG_FIFO_DATA,
				    BCOM_INITIATOR_SCLPC, BCOM_IPR_SCLPC,
				    16*1024*1024);
	if (!lpbfifo.bcom_rx_task)
		goto err_bcom_rx;

	rc = request_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task),
			 mpc52xx_lpbfifo_bcom_irq, 0,
			 "mpc52xx-lpbfifo-rx", &lpbfifo);
	if (rc)
		goto err_bcom_rx_irq;

	lpbfifo.dma_irqs_enabled = 1;

	/* Request the Bestcomm transmit (memory --> fifo) task and IRQ */
	lpbfifo.bcom_tx_task =
		bcom_gen_bd_tx_init(2, res.start + LPBFIFO_REG_FIFO_DATA,
				    BCOM_INITIATOR_SCLPC, BCOM_IPR_SCLPC);
	if (!lpbfifo.bcom_tx_task)
		goto err_bcom_tx;

	lpbfifo.dev = &op->dev;
	return 0;

 err_bcom_tx:
	free_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task), &lpbfifo);
 err_bcom_rx_irq:
	bcom_gen_bd_rx_release(lpbfifo.bcom_rx_task);
 err_bcom_rx:
 err_irq:
	iounmap(lpbfifo.regs);
	lpbfifo.regs = NULL;

	dev_err(&op->dev, "mpc52xx_lpbfifo_probe() failed\n");
	return -ENODEV;
}
static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
{
	size_t transfer_size = req->size - req->pos;
	struct bcom_bd *bd;
	void __iomem *reg;
	u32 *data;
	int i;
	int bit_fields;
	int dma = !(req->flags & MPC52XX_LPBFIFO_FLAG_NO_DMA);
	int write = req->flags & MPC52XX_LPBFIFO_FLAG_WRITE;
	int poll_dma = req->flags & MPC52XX_LPBFIFO_FLAG_POLL_DMA;

	/*                                                               */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);

	/*                       */
	out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000001);
	if (!dma) {
		/*                                                           
                                                              
                                                                
                                                           
                                                                
                                                           
    
                                                   
   */
		if (transfer_size > 512)
			transfer_size = 512;

		/*                         */
		if (write) {
			reg = lpbfifo.regs + LPBFIFO_REG_FIFO_DATA;
			data = req->data + req->pos;
			for (i = 0; i < transfer_size; i += 4)
				out_be32(reg, *data++);
		}

		/*                                       */
		out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000301);
	} else {
		/*                             
    
                                                                    
                                                                 
                                                                   
                                                             
   */
		if (write) {
			out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1e4);
			out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 7);
			lpbfifo.bcom_cur_task = lpbfifo.bcom_tx_task;
		} else {
			out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1ff);
			out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 0);
			lpbfifo.bcom_cur_task = lpbfifo.bcom_rx_task;

			if (poll_dma) {
				if (lpbfifo.dma_irqs_enabled) {
					disable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
					lpbfifo.dma_irqs_enabled = 0;
				}
			} else {
				if (!lpbfifo.dma_irqs_enabled) {
					enable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
					lpbfifo.dma_irqs_enabled = 1;
				}
			}
		}

		bd = bcom_prepare_next_buffer(lpbfifo.bcom_cur_task);
		bd->status = transfer_size;
		if (!write) {
			/*
                                                     
                                                       
                                                    
                                                        
                                                         
                
     
                                                          
                                                       
                                            
    */
			transfer_size += 4; /*        */
		}
		bd->data[0] = req->data_phys + req->pos;
		bcom_submit_next_buffer(lpbfifo.bcom_cur_task, NULL);

		/*                                */
		bit_fields = 0x00000201;

		/*             */
		if (write && (!poll_dma))
			bit_fields |= 0x00000100; /*                    */
		out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, bit_fields);
	}

	/*                                                     */
	out_be32(lpbfifo.regs + LPBFIFO_REG_START_ADDRESS,
		 req->offset + req->pos);
	out_be32(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, transfer_size);

	bit_fields = req->cs << 24 | 0x000008;
	if (!write)
		bit_fields |= 0x010000; /*           */
	out_be32(lpbfifo.regs + LPBFIFO_REG_CONTROL, bit_fields);

	/*             */
	out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
	if (dma)
		bcom_enable(lpbfifo.bcom_cur_task);
}