drivers/staging/cx25821/cx25821-audio-upstream.c - linux - Git at Google

 /*
  *  Driver for the Conexant CX25821 PCIe bridge
  *
  *  Copyright (C) 2009 Conexant Systems Inc.
  *  Authors  <hiep.huynh@conexant.com>, <shu.lin@conexant.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

 #include "cx25821-video.h"
 #include "cx25821-audio-upstream.h"

 #include <linux/fs.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/file.h>
 #include <linux/fcntl.h>
 #include <linux/delay.h>
 #include <asm/uaccess.h>

 MODULE_DESCRIPTION("v4l2 driver module for cx25821 based TV cards");
 MODULE_AUTHOR("Hiep Huynh <hiep.huynh@conexant.com>");
 MODULE_LICENSE("GPL");

 static int _intr_msk =
     FLD_AUD_SRC_RISCI1 | FLD_AUD_SRC_OF | FLD_AUD_SRC_SYNC |
     FLD_AUD_SRC_OPC_ERR;

 int cx25821_sram_channel_setup_upstream_audio(struct cx25821_dev *dev,
 					      struct sram_channel *ch,
 					      unsigned int bpl, u32 risc)
 {
 	unsigned int i, lines;
 	u32 cdt;

 	if (ch->cmds_start == 0) {
 		cx_write(ch->ptr1_reg, 0);
 		cx_write(ch->ptr2_reg, 0);
 		cx_write(ch->cnt2_reg, 0);
 		cx_write(ch->cnt1_reg, 0);
 		return 0;
 	}

 	bpl = (bpl + 7) & ~7;	/* alignment */
 	cdt = ch->cdt;
 	lines = ch->fifo_size / bpl;

 	if (lines > 3) {
 		lines = 3;
 	}

 	BUG_ON(lines < 2);

 	/* write CDT */
 	for (i = 0; i < lines; i++) {
 		cx_write(cdt + 16 * i, ch->fifo_start + bpl * i);
 		cx_write(cdt + 16 * i + 4, 0);
 		cx_write(cdt + 16 * i + 8, 0);
 		cx_write(cdt + 16 * i + 12, 0);
 	}

 	/* write CMDS */
 	cx_write(ch->cmds_start + 0, risc);

 	cx_write(ch->cmds_start + 4, 0);
 	cx_write(ch->cmds_start + 8, cdt);
 	cx_write(ch->cmds_start + 12, AUDIO_CDT_SIZE_QW);
 	cx_write(ch->cmds_start + 16, ch->ctrl_start);

 	//IQ size
 	cx_write(ch->cmds_start + 20, AUDIO_IQ_SIZE_DW);

 	for (i = 24; i < 80; i += 4)
 		cx_write(ch->cmds_start + i, 0);

 	/* fill registers */
 	cx_write(ch->ptr1_reg, ch->fifo_start);
 	cx_write(ch->ptr2_reg, cdt);
 	cx_write(ch->cnt2_reg, AUDIO_CDT_SIZE_QW);
 	cx_write(ch->cnt1_reg, AUDIO_CLUSTER_SIZE_QW - 1);

 	return 0;
 }

 static __le32 *cx25821_risc_field_upstream_audio(struct cx25821_dev *dev,
 						 __le32 * rp,
 						 dma_addr_t databuf_phys_addr,
 						 unsigned int bpl,
 						 int fifo_enable)
 {
 	unsigned int line;
 	struct sram_channel *sram_ch =
 	    &dev->sram_channels[dev->_audio_upstream_channel_select];
 	int offset = 0;

 	/* scan lines */
 	for (line = 0; line < LINES_PER_AUDIO_BUFFER; line++) {
 		*(rp++) = cpu_to_le32(RISC_READ | RISC_SOL | RISC_EOL | bpl);
 		*(rp++) = cpu_to_le32(databuf_phys_addr + offset);
 		*(rp++) = cpu_to_le32(0);	/* bits 63-32 */

 		// Check if we need to enable the FIFO after the first 3 lines
 		// For the upstream audio channel, the risc engine will enable the FIFO.
 		if (fifo_enable && line == 2) {
 			*(rp++) = RISC_WRITECR;
 			*(rp++) = sram_ch->dma_ctl;
 			*(rp++) = sram_ch->fld_aud_fifo_en;
 			*(rp++) = 0x00000020;
 		}

 		offset += AUDIO_LINE_SIZE;
 	}

 	return rp;
 }

 int cx25821_risc_buffer_upstream_audio(struct cx25821_dev *dev,
 				       struct pci_dev *pci,
 				       unsigned int bpl, unsigned int lines)
 {
 	__le32 *rp;
 	int fifo_enable = 0;
 	int frame = 0, i = 0;
 	int frame_size = AUDIO_DATA_BUF_SZ;
 	int databuf_offset = 0;
 	int risc_flag = RISC_CNT_INC;
 	dma_addr_t risc_phys_jump_addr;

 	/* Virtual address of Risc buffer program */
 	rp = dev->_risc_virt_addr;

 	/* sync instruction */
 	*(rp++) = cpu_to_le32(RISC_RESYNC | AUDIO_SYNC_LINE);

 	for (frame = 0; frame < NUM_AUDIO_FRAMES; frame++) {
 		databuf_offset = frame_size * frame;

 		if (frame == 0) {
 			fifo_enable = 1;
 			risc_flag = RISC_CNT_RESET;
 		} else {
 			fifo_enable = 0;
 			risc_flag = RISC_CNT_INC;
 		}

 		//Calculate physical jump address
 		if ((frame + 1) == NUM_AUDIO_FRAMES) {
 			risc_phys_jump_addr =
 			    dev->_risc_phys_start_addr +
 			    RISC_SYNC_INSTRUCTION_SIZE;
 		} else {
 			risc_phys_jump_addr =
 			    dev->_risc_phys_start_addr +
 			    RISC_SYNC_INSTRUCTION_SIZE +
 			    AUDIO_RISC_DMA_BUF_SIZE * (frame + 1);
 		}

 		rp = cx25821_risc_field_upstream_audio(dev, rp,
 						       dev->
 						       _audiodata_buf_phys_addr
 						       + databuf_offset, bpl,
 						       fifo_enable);

 		if (USE_RISC_NOOP_AUDIO) {
 			for (i = 0; i < NUM_NO_OPS; i++) {
 				*(rp++) = cpu_to_le32(RISC_NOOP);
 			}
 		}

 		// Loop to (Nth)FrameRISC or to Start of Risc program & generate IRQ
 		*(rp++) = cpu_to_le32(RISC_JUMP | RISC_IRQ1 | risc_flag);
 		*(rp++) = cpu_to_le32(risc_phys_jump_addr);
 		*(rp++) = cpu_to_le32(0);

 		//Recalculate virtual address based on frame index
 		rp = dev->_risc_virt_addr + RISC_SYNC_INSTRUCTION_SIZE / 4 +
 		    (AUDIO_RISC_DMA_BUF_SIZE * (frame + 1) / 4);
 	}

 	return 0;
 }

 void cx25821_free_memory_audio(struct cx25821_dev *dev)
 {
 	if (dev->_risc_virt_addr) {
 		pci_free_consistent(dev->pci, dev->_audiorisc_size,
 				    dev->_risc_virt_addr, dev->_risc_phys_addr);
 		dev->_risc_virt_addr = NULL;
 	}

 	if (dev->_audiodata_buf_virt_addr) {
 		pci_free_consistent(dev->pci, dev->_audiodata_buf_size,
 				    dev->_audiodata_buf_virt_addr,
 				    dev->_audiodata_buf_phys_addr);
 		dev->_audiodata_buf_virt_addr = NULL;
 	}
 }

 void cx25821_stop_upstream_audio(struct cx25821_dev *dev)
 {
 	struct sram_channel *sram_ch =
 	    &dev->sram_channels[AUDIO_UPSTREAM_SRAM_CHANNEL_B];
 	u32 tmp = 0;

 	if (!dev->_audio_is_running) {
 		printk
 		    ("cx25821: No audio file is currently running so return!\n");
 		return;
 	}
 	//Disable RISC interrupts
 	cx_write(sram_ch->int_msk, 0);

 	//Turn OFF risc and fifo enable in AUD_DMA_CNTRL
 	tmp = cx_read(sram_ch->dma_ctl);
 	cx_write(sram_ch->dma_ctl,
 		 tmp & ~(sram_ch->fld_aud_fifo_en | sram_ch->fld_aud_risc_en));

 	//Clear data buffer memory
 	if (dev->_audiodata_buf_virt_addr)
 		memset(dev->_audiodata_buf_virt_addr, 0,
 		       dev->_audiodata_buf_size);

 	dev->_audio_is_running = 0;
 	dev->_is_first_audio_frame = 0;
 	dev->_audioframe_count = 0;
 	dev->_audiofile_status = END_OF_FILE;

 	if (dev->_irq_audio_queues) {
 		kfree(dev->_irq_audio_queues);
 		dev->_irq_audio_queues = NULL;
 	}

 	if (dev->_audiofilename != NULL)
 		kfree(dev->_audiofilename);
 }

 void cx25821_free_mem_upstream_audio(struct cx25821_dev *dev)
 {
 	if (dev->_audio_is_running) {
 		cx25821_stop_upstream_audio(dev);
 	}

 	cx25821_free_memory_audio(dev);
 }

 int cx25821_get_audio_data(struct cx25821_dev *dev,
 			   struct sram_channel *sram_ch)
 {
 	struct file *myfile;
 	int frame_index_temp = dev->_audioframe_index;
 	int i = 0;
 	int line_size = AUDIO_LINE_SIZE;
 	int frame_size = AUDIO_DATA_BUF_SZ;
 	int frame_offset = frame_size * frame_index_temp;
 	ssize_t vfs_read_retval = 0;
 	char mybuf[line_size];
 	loff_t file_offset = dev->_audioframe_count * frame_size;
 	loff_t pos;
 	mm_segment_t old_fs;

 	if (dev->_audiofile_status == END_OF_FILE)
 		return 0;

 	myfile = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);

 	if (IS_ERR(myfile)) {
 		const int open_errno = -PTR_ERR(myfile);
 		printk("%s(): ERROR opening file(%s) with errno = %d! \n",
 		       __func__, dev->_audiofilename, open_errno);
 		return PTR_ERR(myfile);
 	} else {
 		if (!(myfile->f_op)) {
 			printk("%s: File has no file operations registered!\n",
 			       __func__);
 			filp_close(myfile, NULL);
 			return -EIO;
 		}

 		if (!myfile->f_op->read) {
 			printk("%s: File has no READ operations registered! \n",
 			       __func__);
 			filp_close(myfile, NULL);
 			return -EIO;
 		}

 		pos = myfile->f_pos;
 		old_fs = get_fs();
 		set_fs(KERNEL_DS);

 		for (i = 0; i < dev->_audio_lines_count; i++) {
 			pos = file_offset;

 			vfs_read_retval =
 			    vfs_read(myfile, mybuf, line_size, &pos);

 			if (vfs_read_retval > 0 && vfs_read_retval == line_size
 			    && dev->_audiodata_buf_virt_addr != NULL) {
 				memcpy((void *)(dev->_audiodata_buf_virt_addr +
 						frame_offset / 4), mybuf,
 				       vfs_read_retval);
 			}

 			file_offset += vfs_read_retval;
 			frame_offset += vfs_read_retval;

 			if (vfs_read_retval < line_size) {
 				printk(KERN_INFO
 				       "Done: exit %s() since no more bytes to read from Audio file.\n",
 				       __func__);
 				break;
 			}
 		}

 		if (i > 0)
 			dev->_audioframe_count++;

 		dev->_audiofile_status =
 		    (vfs_read_retval == line_size) ? IN_PROGRESS : END_OF_FILE;

 		set_fs(old_fs);
 		filp_close(myfile, NULL);
 	}

 	return 0;
 }

 static void cx25821_audioups_handler(struct work_struct *work)
 {
 	struct cx25821_dev *dev =
 	    container_of(work, struct cx25821_dev, _audio_work_entry);

 	if (!dev) {
 		printk("ERROR %s(): since container_of(work_struct) FAILED! \n",
 		       __func__);
 		return;
 	}

 	cx25821_get_audio_data(dev,
 			       &dev->sram_channels[dev->
 						   _audio_upstream_channel_select]);
 }

 int cx25821_openfile_audio(struct cx25821_dev *dev,
 			   struct sram_channel *sram_ch)
 {
 	struct file *myfile;
 	int i = 0, j = 0;
 	int line_size = AUDIO_LINE_SIZE;
 	ssize_t vfs_read_retval = 0;
 	char mybuf[line_size];
 	loff_t pos;
 	loff_t offset = (unsigned long)0;
 	mm_segment_t old_fs;

 	myfile = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);

 	if (IS_ERR(myfile)) {
 		const int open_errno = -PTR_ERR(myfile);
 		printk("%s(): ERROR opening file(%s) with errno = %d! \n",
 		       __func__, dev->_audiofilename, open_errno);
 		return PTR_ERR(myfile);
 	} else {
 		if (!(myfile->f_op)) {
 			printk("%s: File has no file operations registered! \n",
 			       __func__);
 			filp_close(myfile, NULL);
 			return -EIO;
 		}

 		if (!myfile->f_op->read) {
 			printk("%s: File has no READ operations registered! \n",
 			       __func__);
 			filp_close(myfile, NULL);
 			return -EIO;
 		}

 		pos = myfile->f_pos;
 		old_fs = get_fs();
 		set_fs(KERNEL_DS);

 		for (j = 0; j < NUM_AUDIO_FRAMES; j++) {
 			for (i = 0; i < dev->_audio_lines_count; i++) {
 				pos = offset;

 				vfs_read_retval =
 				    vfs_read(myfile, mybuf, line_size, &pos);

 				if (vfs_read_retval > 0
 				    && vfs_read_retval == line_size
 				    && dev->_audiodata_buf_virt_addr != NULL) {
 					memcpy((void *)(dev->
 							_audiodata_buf_virt_addr
 							+ offset / 4), mybuf,
 					       vfs_read_retval);
 				}

 				offset += vfs_read_retval;

 				if (vfs_read_retval < line_size) {
 					printk(KERN_INFO
 					       "Done: exit %s() since no more bytes to read from Audio file.\n",
 					       __func__);
 					break;
 				}
 			}

 			if (i > 0) {
 				dev->_audioframe_count++;
 			}

 			if (vfs_read_retval < line_size) {
 				break;
 			}
 		}

 		dev->_audiofile_status =
 		    (vfs_read_retval == line_size) ? IN_PROGRESS : END_OF_FILE;

 		set_fs(old_fs);
 		myfile->f_pos = 0;
 		filp_close(myfile, NULL);
 	}

 	return 0;
 }

 static int cx25821_audio_upstream_buffer_prepare(struct cx25821_dev *dev,
 						 struct sram_channel *sram_ch,
 						 int bpl)
 {
 	int ret = 0;
 	dma_addr_t dma_addr;
 	dma_addr_t data_dma_addr;

 	cx25821_free_memory_audio(dev);

 	dev->_risc_virt_addr =
 	    pci_alloc_consistent(dev->pci, dev->audio_upstream_riscbuf_size,
 				 &dma_addr);
 	dev->_risc_virt_start_addr = dev->_risc_virt_addr;
 	dev->_risc_phys_start_addr = dma_addr;
 	dev->_risc_phys_addr = dma_addr;
 	dev->_audiorisc_size = dev->audio_upstream_riscbuf_size;

 	if (!dev->_risc_virt_addr) {
 		printk
 		    ("cx25821 ERROR: pci_alloc_consistent() FAILED to allocate memory for RISC program! Returning.\n");
 		return -ENOMEM;
 	}
 	//Clear out memory at address
 	memset(dev->_risc_virt_addr, 0, dev->_audiorisc_size);

 	//For Audio Data buffer allocation
 	dev->_audiodata_buf_virt_addr =
 	    pci_alloc_consistent(dev->pci, dev->audio_upstream_databuf_size,
 				 &data_dma_addr);
 	dev->_audiodata_buf_phys_addr = data_dma_addr;
 	dev->_audiodata_buf_size = dev->audio_upstream_databuf_size;

 	if (!dev->_audiodata_buf_virt_addr) {
 		printk
 		    ("cx25821 ERROR: pci_alloc_consistent() FAILED to allocate memory for data buffer! Returning. \n");
 		return -ENOMEM;
 	}
 	//Clear out memory at address
 	memset(dev->_audiodata_buf_virt_addr, 0, dev->_audiodata_buf_size);

 	ret = cx25821_openfile_audio(dev, sram_ch);
 	if (ret < 0)
 		return ret;

 	//Creating RISC programs
 	ret =
 	    cx25821_risc_buffer_upstream_audio(dev, dev->pci, bpl,
 					       dev->_audio_lines_count);
 	if (ret < 0) {
 		printk(KERN_DEBUG
 		       "cx25821 ERROR creating audio upstream RISC programs! \n");
 		goto error;
 	}

 	return 0;

       error:
 	return ret;
 }

 int cx25821_audio_upstream_irq(struct cx25821_dev *dev, int chan_num,
 			       u32 status)
 {
 	int i = 0;
 	u32 int_msk_tmp;
 	struct sram_channel *channel = &dev->sram_channels[chan_num];
 	dma_addr_t risc_phys_jump_addr;
 	__le32 *rp;

 	if (status & FLD_AUD_SRC_RISCI1) {
 		//Get interrupt_index of the program that interrupted
 		u32 prog_cnt = cx_read(channel->gpcnt);

 		//Since we've identified our IRQ, clear our bits from the interrupt mask and interrupt status registers
 		cx_write(channel->int_msk, 0);
 		cx_write(channel->int_stat, cx_read(channel->int_stat));

 		spin_lock(&dev->slock);

 		while (prog_cnt != dev->_last_index_irq) {
 			//Update _last_index_irq
 			if (dev->_last_index_irq < (NUMBER_OF_PROGRAMS - 1)) {
 				dev->_last_index_irq++;
 			} else {
 				dev->_last_index_irq = 0;
 			}

 			dev->_audioframe_index = dev->_last_index_irq;

 			queue_work(dev->_irq_audio_queues,
 				   &dev->_audio_work_entry);
 		}

 		if (dev->_is_first_audio_frame) {
 			dev->_is_first_audio_frame = 0;

 			if (dev->_risc_virt_start_addr != NULL) {
 				risc_phys_jump_addr =
 				    dev->_risc_phys_start_addr +
 				    RISC_SYNC_INSTRUCTION_SIZE +
 				    AUDIO_RISC_DMA_BUF_SIZE;

 				rp = cx25821_risc_field_upstream_audio(dev,
 								       dev->
 								       _risc_virt_start_addr
 								       + 1,
 								       dev->
 								       _audiodata_buf_phys_addr,
 								       AUDIO_LINE_SIZE,
 								       FIFO_DISABLE);

 				if (USE_RISC_NOOP_AUDIO) {
 					for (i = 0; i < NUM_NO_OPS; i++) {
 						*(rp++) =
 						    cpu_to_le32(RISC_NOOP);
 					}
 				}
 				// Jump to 2nd Audio Frame
 				*(rp++) =
 				    cpu_to_le32(RISC_JUMP | RISC_IRQ1 |
 						RISC_CNT_RESET);
 				*(rp++) = cpu_to_le32(risc_phys_jump_addr);
 				*(rp++) = cpu_to_le32(0);
 			}
 		}

 		spin_unlock(&dev->slock);
 	} else {
 		if (status & FLD_AUD_SRC_OF)
 			printk("%s: Audio Received Overflow Error Interrupt!\n",
 			       __func__);

 		if (status & FLD_AUD_SRC_SYNC)
 			printk("%s: Audio Received Sync Error Interrupt!\n",
 			       __func__);

 		if (status & FLD_AUD_SRC_OPC_ERR)
 			printk("%s: Audio Received OpCode Error Interrupt!\n",
 			       __func__);

 		// Read and write back the interrupt status register to clear our bits
 		cx_write(channel->int_stat, cx_read(channel->int_stat));
 	}

 	if (dev->_audiofile_status == END_OF_FILE) {
 		printk("cx25821: EOF Channel Audio Framecount = %d\n",
 		       dev->_audioframe_count);
 		return -1;
 	}
 	//ElSE, set the interrupt mask register, re-enable irq.
 	int_msk_tmp = cx_read(channel->int_msk);
 	cx_write(channel->int_msk, int_msk_tmp |= _intr_msk);

 	return 0;
 }

 static irqreturn_t cx25821_upstream_irq_audio(int irq, void *dev_id)
 {
 	struct cx25821_dev *dev = dev_id;
 	u32 msk_stat, audio_status;
 	int handled = 0;
 	struct sram_channel *sram_ch;

 	if (!dev)
 		return -1;

 	sram_ch = &dev->sram_channels[dev->_audio_upstream_channel_select];

 	msk_stat = cx_read(sram_ch->int_mstat);
 	audio_status = cx_read(sram_ch->int_stat);

 	// Only deal with our interrupt
 	if (audio_status) {
 		handled =
 		    cx25821_audio_upstream_irq(dev,
 					       dev->
 					       _audio_upstream_channel_select,
 					       audio_status);
 	}

 	if (handled < 0) {
 		cx25821_stop_upstream_audio(dev);
 	} else {
 		handled += handled;
 	}

 	return IRQ_RETVAL(handled);
 }

 static void cx25821_wait_fifo_enable(struct cx25821_dev *dev,
 				     struct sram_channel *sram_ch)
 {
 	int count = 0;
 	u32 tmp;

 	do {
 		//Wait 10 microsecond before checking to see if the FIFO is turned ON.
 		udelay(10);

 		tmp = cx_read(sram_ch->dma_ctl);

 		if (count++ > 1000)	//10 millisecond timeout
 		{
 			printk
 			    ("cx25821 ERROR: %s() fifo is NOT turned on. Timeout!\n",
 			     __func__);
 			return;
 		}

 	} while (!(tmp & sram_ch->fld_aud_fifo_en));

 }

 int cx25821_start_audio_dma_upstream(struct cx25821_dev *dev,
 				     struct sram_channel *sram_ch)
 {
 	u32 tmp = 0;
 	int err = 0;

 	// Set the physical start address of the RISC program in the initial program counter(IPC) member of the CMDS.
 	cx_write(sram_ch->cmds_start + 0, dev->_risc_phys_addr);
 	cx_write(sram_ch->cmds_start + 4, 0);	/* Risc IPC High 64 bits 63-32 */

 	/* reset counter */
 	cx_write(sram_ch->gpcnt_ctl, 3);

 	//Set the line length       (It looks like we do not need to set the line length)
 	cx_write(sram_ch->aud_length, AUDIO_LINE_SIZE & FLD_AUD_DST_LN_LNGTH);

 	//Set the input mode to 16-bit
 	tmp = cx_read(sram_ch->aud_cfg);
 	tmp |=
 	    FLD_AUD_SRC_ENABLE | FLD_AUD_DST_PK_MODE | FLD_AUD_CLK_ENABLE |
 	    FLD_AUD_MASTER_MODE | FLD_AUD_CLK_SELECT_PLL_D | FLD_AUD_SONY_MODE;
 	cx_write(sram_ch->aud_cfg, tmp);

 	// Read and write back the interrupt status register to clear it
 	tmp = cx_read(sram_ch->int_stat);
 	cx_write(sram_ch->int_stat, tmp);

 	// Clear our bits from the interrupt status register.
 	cx_write(sram_ch->int_stat, _intr_msk);

 	//Set the interrupt mask register, enable irq.
 	cx_set(PCI_INT_MSK, cx_read(PCI_INT_MSK) | (1 << sram_ch->irq_bit));
 	tmp = cx_read(sram_ch->int_msk);
 	cx_write(sram_ch->int_msk, tmp |= _intr_msk);

 	err =
 	    request_irq(dev->pci->irq, cx25821_upstream_irq_audio,
 			IRQF_SHARED | IRQF_DISABLED, dev->name, dev);
 	if (err < 0) {
 		printk(KERN_ERR "%s: can't get upstream IRQ %d\n", dev->name,
 		       dev->pci->irq);
 		goto fail_irq;
 	}

 	// Start the DMA  engine
 	tmp = cx_read(sram_ch->dma_ctl);
 	cx_set(sram_ch->dma_ctl, tmp | sram_ch->fld_aud_risc_en);

 	dev->_audio_is_running = 1;
 	dev->_is_first_audio_frame = 1;

 	// The fifo_en bit turns on by the first Risc program
 	cx25821_wait_fifo_enable(dev, sram_ch);

 	return 0;

       fail_irq:
 	cx25821_dev_unregister(dev);
 	return err;
 }

 int cx25821_audio_upstream_init(struct cx25821_dev *dev, int channel_select)
 {
 	struct sram_channel *sram_ch;
 	int retval = 0;
 	int err = 0;
 	int str_length = 0;

 	if (dev->_audio_is_running) {
 		printk("Audio Channel is still running so return!\n");
 		return 0;
 	}

 	dev->_audio_upstream_channel_select = channel_select;
 	sram_ch = &dev->sram_channels[channel_select];

 	//Work queue
 	INIT_WORK(&dev->_audio_work_entry, cx25821_audioups_handler);
 	dev->_irq_audio_queues =
 	    create_singlethread_workqueue("cx25821_audioworkqueue");

 	if (!dev->_irq_audio_queues) {
 		printk
 		    ("cx25821 ERROR: create_singlethread_workqueue() for Audio FAILED!\n");
 		return -ENOMEM;
 	}

 	dev->_last_index_irq = 0;
 	dev->_audio_is_running = 0;
 	dev->_audioframe_count = 0;
 	dev->_audiofile_status = RESET_STATUS;
 	dev->_audio_lines_count = LINES_PER_AUDIO_BUFFER;
 	_line_size = AUDIO_LINE_SIZE;

 	if (dev->input_audiofilename) {
 		str_length = strlen(dev->input_audiofilename);
 		dev->_audiofilename =
 		    (char *)kmalloc(str_length + 1, GFP_KERNEL);

 		if (!dev->_audiofilename)
 			goto error;

 		memcpy(dev->_audiofilename, dev->input_audiofilename,
 		       str_length + 1);

 		//Default if filename is empty string
 		if (strcmp(dev->input_audiofilename, "") == 0) {
 			dev->_audiofilename = "/root/audioGOOD.wav";
 		}
 	} else {
 		str_length = strlen(_defaultAudioName);
 		dev->_audiofilename =
 		    (char *)kmalloc(str_length + 1, GFP_KERNEL);

 		if (!dev->_audiofilename)
 			goto error;

 		memcpy(dev->_audiofilename, _defaultAudioName, str_length + 1);
 	}

 	retval =
 	    cx25821_sram_channel_setup_upstream_audio(dev, sram_ch, _line_size,
 						      0);

 	dev->audio_upstream_riscbuf_size =
 	    AUDIO_RISC_DMA_BUF_SIZE * NUM_AUDIO_PROGS +
 	    RISC_SYNC_INSTRUCTION_SIZE;
 	dev->audio_upstream_databuf_size = AUDIO_DATA_BUF_SZ * NUM_AUDIO_PROGS;

 	//Allocating buffers and prepare RISC program
 	retval =
 	    cx25821_audio_upstream_buffer_prepare(dev, sram_ch, _line_size);
 	if (retval < 0) {
 		printk(KERN_ERR
 		       "%s: Failed to set up Audio upstream buffers!\n",
 		       dev->name);
 		goto error;
 	}
 	//Start RISC engine
 	cx25821_start_audio_dma_upstream(dev, sram_ch);

 	return 0;

       error:
 	cx25821_dev_unregister(dev);

 	return err;
 }
	/*
	* Driver for the Conexant CX25821 PCIe bridge
	*
	* Copyright (C) 2009 Conexant Systems Inc.
	* Authors <hiep.huynh@conexant.com>, <shu.lin@conexant.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
	*/

	#include "cx25821-video.h"
	#include "cx25821-audio-upstream.h"

	#include <linux/fs.h>
	#include <linux/errno.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/syscalls.h>
	#include <linux/file.h>
	#include <linux/fcntl.h>
	#include <linux/delay.h>
	#include <asm/uaccess.h>

	MODULE_DESCRIPTION("v4l2 driver module for cx25821 based TV cards");
	MODULE_AUTHOR("Hiep Huynh <hiep.huynh@conexant.com>");
	MODULE_LICENSE("GPL");

	static int _intr_msk =
	FLD_AUD_SRC_RISCI1 \| FLD_AUD_SRC_OF \| FLD_AUD_SRC_SYNC \|
	FLD_AUD_SRC_OPC_ERR;

	int cx25821_sram_channel_setup_upstream_audio(struct cx25821_dev *dev,
	struct sram_channel *ch,
	unsigned int bpl, u32 risc)
	{
	unsigned int i, lines;
	u32 cdt;

	if (ch->cmds_start == 0) {
	cx_write(ch->ptr1_reg, 0);
	cx_write(ch->ptr2_reg, 0);
	cx_write(ch->cnt2_reg, 0);
	cx_write(ch->cnt1_reg, 0);
	return 0;
	}

	bpl = (bpl + 7) & ~7; /* alignment */
	cdt = ch->cdt;
	lines = ch->fifo_size / bpl;

	if (lines > 3) {
	lines = 3;
	}

	BUG_ON(lines < 2);

	/* write CDT */
	for (i = 0; i < lines; i++) {
	cx_write(cdt + 16 * i, ch->fifo_start + bpl * i);
	cx_write(cdt + 16 * i + 4, 0);
	cx_write(cdt + 16 * i + 8, 0);
	cx_write(cdt + 16 * i + 12, 0);
	}

	/* write CMDS */
	cx_write(ch->cmds_start + 0, risc);

	cx_write(ch->cmds_start + 4, 0);
	cx_write(ch->cmds_start + 8, cdt);
	cx_write(ch->cmds_start + 12, AUDIO_CDT_SIZE_QW);
	cx_write(ch->cmds_start + 16, ch->ctrl_start);

	//IQ size
	cx_write(ch->cmds_start + 20, AUDIO_IQ_SIZE_DW);

	for (i = 24; i < 80; i += 4)
	cx_write(ch->cmds_start + i, 0);

	/* fill registers */
	cx_write(ch->ptr1_reg, ch->fifo_start);
	cx_write(ch->ptr2_reg, cdt);
	cx_write(ch->cnt2_reg, AUDIO_CDT_SIZE_QW);
	cx_write(ch->cnt1_reg, AUDIO_CLUSTER_SIZE_QW - 1);

	return 0;
	}

	static __le32 cx25821_risc_field_upstream_audio(struct cx25821_dev dev,
	__le32 * rp,
	dma_addr_t databuf_phys_addr,
	unsigned int bpl,
	int fifo_enable)
	{
	unsigned int line;
	struct sram_channel *sram_ch =
	&dev->sram_channels[dev->_audio_upstream_channel_select];
	int offset = 0;

	/* scan lines */
	for (line = 0; line < LINES_PER_AUDIO_BUFFER; line++) {
	*(rp++) = cpu_to_le32(RISC_READ \| RISC_SOL \| RISC_EOL \| bpl);
	*(rp++) = cpu_to_le32(databuf_phys_addr + offset);
	(rp++) = cpu_to_le32(0); / bits 63-32 */

	// Check if we need to enable the FIFO after the first 3 lines
	// For the upstream audio channel, the risc engine will enable the FIFO.
	if (fifo_enable && line == 2) {
	*(rp++) = RISC_WRITECR;
	*(rp++) = sram_ch->dma_ctl;
	*(rp++) = sram_ch->fld_aud_fifo_en;
	*(rp++) = 0x00000020;
	}

	offset += AUDIO_LINE_SIZE;
	}

	return rp;
	}

	int cx25821_risc_buffer_upstream_audio(struct cx25821_dev *dev,
	struct pci_dev *pci,
	unsigned int bpl, unsigned int lines)
	{
	__le32 *rp;
	int fifo_enable = 0;
	int frame = 0, i = 0;
	int frame_size = AUDIO_DATA_BUF_SZ;
	int databuf_offset = 0;
	int risc_flag = RISC_CNT_INC;
	dma_addr_t risc_phys_jump_addr;

	/* Virtual address of Risc buffer program */
	rp = dev->_risc_virt_addr;

	/* sync instruction */
	*(rp++) = cpu_to_le32(RISC_RESYNC \| AUDIO_SYNC_LINE);

	for (frame = 0; frame < NUM_AUDIO_FRAMES; frame++) {
	databuf_offset = frame_size * frame;

	if (frame == 0) {
	fifo_enable = 1;
	risc_flag = RISC_CNT_RESET;
	} else {
	fifo_enable = 0;
	risc_flag = RISC_CNT_INC;
	}

	//Calculate physical jump address
	if ((frame + 1) == NUM_AUDIO_FRAMES) {
	risc_phys_jump_addr =
	dev->_risc_phys_start_addr +
	RISC_SYNC_INSTRUCTION_SIZE;
	} else {
	risc_phys_jump_addr =
	dev->_risc_phys_start_addr +
	RISC_SYNC_INSTRUCTION_SIZE +
	AUDIO_RISC_DMA_BUF_SIZE * (frame + 1);
	}

	rp = cx25821_risc_field_upstream_audio(dev, rp,
	dev->
	_audiodata_buf_phys_addr
	+ databuf_offset, bpl,
	fifo_enable);

	if (USE_RISC_NOOP_AUDIO) {
	for (i = 0; i < NUM_NO_OPS; i++) {
	*(rp++) = cpu_to_le32(RISC_NOOP);
	}
	}

	// Loop to (Nth)FrameRISC or to Start of Risc program & generate IRQ
	*(rp++) = cpu_to_le32(RISC_JUMP \| RISC_IRQ1 \| risc_flag);
	*(rp++) = cpu_to_le32(risc_phys_jump_addr);
	*(rp++) = cpu_to_le32(0);

	//Recalculate virtual address based on frame index
	rp = dev->_risc_virt_addr + RISC_SYNC_INSTRUCTION_SIZE / 4 +
	(AUDIO_RISC_DMA_BUF_SIZE * (frame + 1) / 4);
	}

	return 0;
	}

	void cx25821_free_memory_audio(struct cx25821_dev *dev)
	{
	if (dev->_risc_virt_addr) {
	pci_free_consistent(dev->pci, dev->_audiorisc_size,
	dev->_risc_virt_addr, dev->_risc_phys_addr);
	dev->_risc_virt_addr = NULL;
	}

	if (dev->_audiodata_buf_virt_addr) {
	pci_free_consistent(dev->pci, dev->_audiodata_buf_size,
	dev->_audiodata_buf_virt_addr,
	dev->_audiodata_buf_phys_addr);
	dev->_audiodata_buf_virt_addr = NULL;
	}
	}

	void cx25821_stop_upstream_audio(struct cx25821_dev *dev)
	{
	struct sram_channel *sram_ch =
	&dev->sram_channels[AUDIO_UPSTREAM_SRAM_CHANNEL_B];
	u32 tmp = 0;

	if (!dev->_audio_is_running) {
	printk
	("cx25821: No audio file is currently running so return!\n");
	return;
	}
	//Disable RISC interrupts
	cx_write(sram_ch->int_msk, 0);

	//Turn OFF risc and fifo enable in AUD_DMA_CNTRL
	tmp = cx_read(sram_ch->dma_ctl);
	cx_write(sram_ch->dma_ctl,
	tmp & ~(sram_ch->fld_aud_fifo_en \| sram_ch->fld_aud_risc_en));

	//Clear data buffer memory
	if (dev->_audiodata_buf_virt_addr)
	memset(dev->_audiodata_buf_virt_addr, 0,
	dev->_audiodata_buf_size);

	dev->_audio_is_running = 0;
	dev->_is_first_audio_frame = 0;
	dev->_audioframe_count = 0;
	dev->_audiofile_status = END_OF_FILE;

	if (dev->_irq_audio_queues) {
	kfree(dev->_irq_audio_queues);
	dev->_irq_audio_queues = NULL;
	}

	if (dev->_audiofilename != NULL)
	kfree(dev->_audiofilename);
	}

	void cx25821_free_mem_upstream_audio(struct cx25821_dev *dev)
	{
	if (dev->_audio_is_running) {
	cx25821_stop_upstream_audio(dev);
	}

	cx25821_free_memory_audio(dev);
	}

	int cx25821_get_audio_data(struct cx25821_dev *dev,
	struct sram_channel *sram_ch)
	{
	struct file *myfile;
	int frame_index_temp = dev->_audioframe_index;
	int i = 0;
	int line_size = AUDIO_LINE_SIZE;
	int frame_size = AUDIO_DATA_BUF_SZ;
	int frame_offset = frame_size * frame_index_temp;
	ssize_t vfs_read_retval = 0;
	char mybuf[line_size];
	loff_t file_offset = dev->_audioframe_count * frame_size;
	loff_t pos;
	mm_segment_t old_fs;

	if (dev->_audiofile_status == END_OF_FILE)
	return 0;

	myfile = filp_open(dev->_audiofilename, O_RDONLY \| O_LARGEFILE, 0);

	if (IS_ERR(myfile)) {
	const int open_errno = -PTR_ERR(myfile);
	printk("%s(): ERROR opening file(%s) with errno = %d! \n",
	__func__, dev->_audiofilename, open_errno);
	return PTR_ERR(myfile);
	} else {
	if (!(myfile->f_op)) {
	printk("%s: File has no file operations registered!\n",
	__func__);
	filp_close(myfile, NULL);
	return -EIO;
	}

	if (!myfile->f_op->read) {
	printk("%s: File has no READ operations registered! \n",
	__func__);
	filp_close(myfile, NULL);
	return -EIO;
	}

	pos = myfile->f_pos;
	old_fs = get_fs();
	set_fs(KERNEL_DS);

	for (i = 0; i < dev->_audio_lines_count; i++) {
	pos = file_offset;

	vfs_read_retval =
	vfs_read(myfile, mybuf, line_size, &pos);

	if (vfs_read_retval > 0 && vfs_read_retval == line_size
	&& dev->_audiodata_buf_virt_addr != NULL) {
	memcpy((void *)(dev->_audiodata_buf_virt_addr +
	frame_offset / 4), mybuf,
	vfs_read_retval);
	}

	file_offset += vfs_read_retval;
	frame_offset += vfs_read_retval;

	if (vfs_read_retval < line_size) {
	printk(KERN_INFO
	"Done: exit %s() since no more bytes to read from Audio file.\n",
	__func__);
	break;
	}
	}

	if (i > 0)
	dev->_audioframe_count++;

	dev->_audiofile_status =
	(vfs_read_retval == line_size) ? IN_PROGRESS : END_OF_FILE;

	set_fs(old_fs);
	filp_close(myfile, NULL);
	}

	return 0;
	}

	static void cx25821_audioups_handler(struct work_struct *work)
	{
	struct cx25821_dev *dev =
	container_of(work, struct cx25821_dev, _audio_work_entry);

	if (!dev) {
	printk("ERROR %s(): since container_of(work_struct) FAILED! \n",
	__func__);
	return;
	}

	cx25821_get_audio_data(dev,
	&dev->sram_channels[dev->
	_audio_upstream_channel_select]);
	}

	int cx25821_openfile_audio(struct cx25821_dev *dev,
	struct sram_channel *sram_ch)
	{
	struct file *myfile;
	int i = 0, j = 0;
	int line_size = AUDIO_LINE_SIZE;
	ssize_t vfs_read_retval = 0;
	char mybuf[line_size];
	loff_t pos;
	loff_t offset = (unsigned long)0;
	mm_segment_t old_fs;

	myfile = filp_open(dev->_audiofilename, O_RDONLY \| O_LARGEFILE, 0);

	if (IS_ERR(myfile)) {
	const int open_errno = -PTR_ERR(myfile);
	printk("%s(): ERROR opening file(%s) with errno = %d! \n",
	__func__, dev->_audiofilename, open_errno);
	return PTR_ERR(myfile);
	} else {
	if (!(myfile->f_op)) {
	printk("%s: File has no file operations registered! \n",
	__func__);
	filp_close(myfile, NULL);
	return -EIO;
	}

	if (!myfile->f_op->read) {
	printk("%s: File has no READ operations registered! \n",
	__func__);
	filp_close(myfile, NULL);
	return -EIO;
	}

	pos = myfile->f_pos;
	old_fs = get_fs();
	set_fs(KERNEL_DS);

	for (j = 0; j < NUM_AUDIO_FRAMES; j++) {
	for (i = 0; i < dev->_audio_lines_count; i++) {
	pos = offset;

	vfs_read_retval =
	vfs_read(myfile, mybuf, line_size, &pos);

	if (vfs_read_retval > 0
	&& vfs_read_retval == line_size
	&& dev->_audiodata_buf_virt_addr != NULL) {
	memcpy((void *)(dev->
	_audiodata_buf_virt_addr
	+ offset / 4), mybuf,
	vfs_read_retval);
	}

	offset += vfs_read_retval;

	if (vfs_read_retval < line_size) {
	printk(KERN_INFO
	"Done: exit %s() since no more bytes to read from Audio file.\n",
	__func__);
	break;
	}
	}

	if (i > 0) {
	dev->_audioframe_count++;
	}

	if (vfs_read_retval < line_size) {
	break;
	}
	}

	dev->_audiofile_status =
	(vfs_read_retval == line_size) ? IN_PROGRESS : END_OF_FILE;

	set_fs(old_fs);
	myfile->f_pos = 0;
	filp_close(myfile, NULL);
	}

	return 0;
	}

	static int cx25821_audio_upstream_buffer_prepare(struct cx25821_dev *dev,
	struct sram_channel *sram_ch,
	int bpl)
	{
	int ret = 0;
	dma_addr_t dma_addr;
	dma_addr_t data_dma_addr;

	cx25821_free_memory_audio(dev);

	dev->_risc_virt_addr =
	pci_alloc_consistent(dev->pci, dev->audio_upstream_riscbuf_size,
	&dma_addr);
	dev->_risc_virt_start_addr = dev->_risc_virt_addr;
	dev->_risc_phys_start_addr = dma_addr;
	dev->_risc_phys_addr = dma_addr;
	dev->_audiorisc_size = dev->audio_upstream_riscbuf_size;

	if (!dev->_risc_virt_addr) {
	printk
	("cx25821 ERROR: pci_alloc_consistent() FAILED to allocate memory for RISC program! Returning.\n");
	return -ENOMEM;
	}
	//Clear out memory at address
	memset(dev->_risc_virt_addr, 0, dev->_audiorisc_size);

	//For Audio Data buffer allocation
	dev->_audiodata_buf_virt_addr =
	pci_alloc_consistent(dev->pci, dev->audio_upstream_databuf_size,
	&data_dma_addr);
	dev->_audiodata_buf_phys_addr = data_dma_addr;
	dev->_audiodata_buf_size = dev->audio_upstream_databuf_size;

	if (!dev->_audiodata_buf_virt_addr) {
	printk
	("cx25821 ERROR: pci_alloc_consistent() FAILED to allocate memory for data buffer! Returning. \n");
	return -ENOMEM;
	}
	//Clear out memory at address
	memset(dev->_audiodata_buf_virt_addr, 0, dev->_audiodata_buf_size);

	ret = cx25821_openfile_audio(dev, sram_ch);
	if (ret < 0)
	return ret;

	//Creating RISC programs
	ret =
	cx25821_risc_buffer_upstream_audio(dev, dev->pci, bpl,
	dev->_audio_lines_count);
	if (ret < 0) {
	printk(KERN_DEBUG
	"cx25821 ERROR creating audio upstream RISC programs! \n");
	goto error;
	}

	return 0;

	error:
	return ret;
	}

	int cx25821_audio_upstream_irq(struct cx25821_dev *dev, int chan_num,
	u32 status)
	{
	int i = 0;
	u32 int_msk_tmp;
	struct sram_channel *channel = &dev->sram_channels[chan_num];
	dma_addr_t risc_phys_jump_addr;
	__le32 *rp;

	if (status & FLD_AUD_SRC_RISCI1) {
	//Get interrupt_index of the program that interrupted
	u32 prog_cnt = cx_read(channel->gpcnt);

	//Since we've identified our IRQ, clear our bits from the interrupt mask and interrupt status registers
	cx_write(channel->int_msk, 0);
	cx_write(channel->int_stat, cx_read(channel->int_stat));

	spin_lock(&dev->slock);

	while (prog_cnt != dev->_last_index_irq) {
	//Update _last_index_irq
	if (dev->_last_index_irq < (NUMBER_OF_PROGRAMS - 1)) {
	dev->_last_index_irq++;
	} else {
	dev->_last_index_irq = 0;
	}

	dev->_audioframe_index = dev->_last_index_irq;

	queue_work(dev->_irq_audio_queues,
	&dev->_audio_work_entry);
	}

	if (dev->_is_first_audio_frame) {
	dev->_is_first_audio_frame = 0;

	if (dev->_risc_virt_start_addr != NULL) {
	risc_phys_jump_addr =
	dev->_risc_phys_start_addr +
	RISC_SYNC_INSTRUCTION_SIZE +
	AUDIO_RISC_DMA_BUF_SIZE;

	rp = cx25821_risc_field_upstream_audio(dev,
	dev->
	_risc_virt_start_addr
	+ 1,
	dev->
	_audiodata_buf_phys_addr,
	AUDIO_LINE_SIZE,
	FIFO_DISABLE);

	if (USE_RISC_NOOP_AUDIO) {
	for (i = 0; i < NUM_NO_OPS; i++) {
	*(rp++) =
	cpu_to_le32(RISC_NOOP);
	}
	}
	// Jump to 2nd Audio Frame
	*(rp++) =
	cpu_to_le32(RISC_JUMP \| RISC_IRQ1 \|
	RISC_CNT_RESET);
	*(rp++) = cpu_to_le32(risc_phys_jump_addr);
	*(rp++) = cpu_to_le32(0);
	}
	}

	spin_unlock(&dev->slock);
	} else {
	if (status & FLD_AUD_SRC_OF)
	printk("%s: Audio Received Overflow Error Interrupt!\n",
	__func__);

	if (status & FLD_AUD_SRC_SYNC)
	printk("%s: Audio Received Sync Error Interrupt!\n",
	__func__);

	if (status & FLD_AUD_SRC_OPC_ERR)
	printk("%s: Audio Received OpCode Error Interrupt!\n",
	__func__);

	// Read and write back the interrupt status register to clear our bits
	cx_write(channel->int_stat, cx_read(channel->int_stat));
	}

	if (dev->_audiofile_status == END_OF_FILE) {
	printk("cx25821: EOF Channel Audio Framecount = %d\n",
	dev->_audioframe_count);
	return -1;
	}
	//ElSE, set the interrupt mask register, re-enable irq.
	int_msk_tmp = cx_read(channel->int_msk);
	cx_write(channel->int_msk, int_msk_tmp \|= _intr_msk);

	return 0;
	}

	static irqreturn_t cx25821_upstream_irq_audio(int irq, void *dev_id)
	{
	struct cx25821_dev *dev = dev_id;
	u32 msk_stat, audio_status;
	int handled = 0;
	struct sram_channel *sram_ch;

	if (!dev)
	return -1;

	sram_ch = &dev->sram_channels[dev->_audio_upstream_channel_select];

	msk_stat = cx_read(sram_ch->int_mstat);
	audio_status = cx_read(sram_ch->int_stat);

	// Only deal with our interrupt
	if (audio_status) {
	handled =
	cx25821_audio_upstream_irq(dev,
	dev->
	_audio_upstream_channel_select,
	audio_status);
	}

	if (handled < 0) {
	cx25821_stop_upstream_audio(dev);
	} else {
	handled += handled;
	}

	return IRQ_RETVAL(handled);
	}

	static void cx25821_wait_fifo_enable(struct cx25821_dev *dev,
	struct sram_channel *sram_ch)
	{
	int count = 0;
	u32 tmp;

	do {
	//Wait 10 microsecond before checking to see if the FIFO is turned ON.
	udelay(10);

	tmp = cx_read(sram_ch->dma_ctl);

	if (count++ > 1000) //10 millisecond timeout
	{
	printk
	("cx25821 ERROR: %s() fifo is NOT turned on. Timeout!\n",
	__func__);
	return;
	}

	} while (!(tmp & sram_ch->fld_aud_fifo_en));

	}

	int cx25821_start_audio_dma_upstream(struct cx25821_dev *dev,
	struct sram_channel *sram_ch)
	{
	u32 tmp = 0;
	int err = 0;

	// Set the physical start address of the RISC program in the initial program counter(IPC) member of the CMDS.
	cx_write(sram_ch->cmds_start + 0, dev->_risc_phys_addr);
	cx_write(sram_ch->cmds_start + 4, 0); /* Risc IPC High 64 bits 63-32 */

	/* reset counter */
	cx_write(sram_ch->gpcnt_ctl, 3);

	//Set the line length (It looks like we do not need to set the line length)
	cx_write(sram_ch->aud_length, AUDIO_LINE_SIZE & FLD_AUD_DST_LN_LNGTH);

	//Set the input mode to 16-bit
	tmp = cx_read(sram_ch->aud_cfg);
	tmp \|=
	FLD_AUD_SRC_ENABLE \| FLD_AUD_DST_PK_MODE \| FLD_AUD_CLK_ENABLE \|
	FLD_AUD_MASTER_MODE \| FLD_AUD_CLK_SELECT_PLL_D \| FLD_AUD_SONY_MODE;
	cx_write(sram_ch->aud_cfg, tmp);

	// Read and write back the interrupt status register to clear it
	tmp = cx_read(sram_ch->int_stat);
	cx_write(sram_ch->int_stat, tmp);

	// Clear our bits from the interrupt status register.
	cx_write(sram_ch->int_stat, _intr_msk);

	//Set the interrupt mask register, enable irq.
	cx_set(PCI_INT_MSK, cx_read(PCI_INT_MSK) \| (1 << sram_ch->irq_bit));
	tmp = cx_read(sram_ch->int_msk);
	cx_write(sram_ch->int_msk, tmp \|= _intr_msk);

	err =
	request_irq(dev->pci->irq, cx25821_upstream_irq_audio,
	IRQF_SHARED \| IRQF_DISABLED, dev->name, dev);
	if (err < 0) {
	printk(KERN_ERR "%s: can't get upstream IRQ %d\n", dev->name,
	dev->pci->irq);
	goto fail_irq;
	}

	// Start the DMA engine
	tmp = cx_read(sram_ch->dma_ctl);
	cx_set(sram_ch->dma_ctl, tmp \| sram_ch->fld_aud_risc_en);

	dev->_audio_is_running = 1;
	dev->_is_first_audio_frame = 1;

	// The fifo_en bit turns on by the first Risc program
	cx25821_wait_fifo_enable(dev, sram_ch);

	return 0;

	fail_irq:
	cx25821_dev_unregister(dev);
	return err;
	}

	int cx25821_audio_upstream_init(struct cx25821_dev *dev, int channel_select)
	{
	struct sram_channel *sram_ch;
	int retval = 0;
	int err = 0;
	int str_length = 0;

	if (dev->_audio_is_running) {
	printk("Audio Channel is still running so return!\n");
	return 0;
	}

	dev->_audio_upstream_channel_select = channel_select;
	sram_ch = &dev->sram_channels[channel_select];

	//Work queue
	INIT_WORK(&dev->_audio_work_entry, cx25821_audioups_handler);
	dev->_irq_audio_queues =
	create_singlethread_workqueue("cx25821_audioworkqueue");

	if (!dev->_irq_audio_queues) {
	printk
	("cx25821 ERROR: create_singlethread_workqueue() for Audio FAILED!\n");
	return -ENOMEM;
	}

	dev->_last_index_irq = 0;
	dev->_audio_is_running = 0;
	dev->_audioframe_count = 0;
	dev->_audiofile_status = RESET_STATUS;
	dev->_audio_lines_count = LINES_PER_AUDIO_BUFFER;
	_line_size = AUDIO_LINE_SIZE;

	if (dev->input_audiofilename) {
	str_length = strlen(dev->input_audiofilename);
	dev->_audiofilename =
	(char *)kmalloc(str_length + 1, GFP_KERNEL);

	if (!dev->_audiofilename)
	goto error;

	memcpy(dev->_audiofilename, dev->input_audiofilename,
	str_length + 1);

	//Default if filename is empty string
	if (strcmp(dev->input_audiofilename, "") == 0) {
	dev->_audiofilename = "/root/audioGOOD.wav";
	}
	} else {
	str_length = strlen(_defaultAudioName);
	dev->_audiofilename =
	(char *)kmalloc(str_length + 1, GFP_KERNEL);

	if (!dev->_audiofilename)
	goto error;

	memcpy(dev->_audiofilename, _defaultAudioName, str_length + 1);
	}

	retval =
	cx25821_sram_channel_setup_upstream_audio(dev, sram_ch, _line_size,
	0);

	dev->audio_upstream_riscbuf_size =
	AUDIO_RISC_DMA_BUF_SIZE * NUM_AUDIO_PROGS +
	RISC_SYNC_INSTRUCTION_SIZE;
	dev->audio_upstream_databuf_size = AUDIO_DATA_BUF_SZ * NUM_AUDIO_PROGS;

	//Allocating buffers and prepare RISC program
	retval =
	cx25821_audio_upstream_buffer_prepare(dev, sram_ch, _line_size);
	if (retval < 0) {
	printk(KERN_ERR
	"%s: Failed to set up Audio upstream buffers!\n",
	dev->name);
	goto error;
	}
	//Start RISC engine
	cx25821_start_audio_dma_upstream(dev, sram_ch);

	return 0;

	error:
	cx25821_dev_unregister(dev);

	return err;
	}