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mcbsp.c

/*
 * linux/arch/arm/plat-omap/mcbsp.c
 *
 * Copyright (C) 2004 Nokia Corporation
 * Author: Samuel Ortiz <samuel.ortiz@nokia.com>
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Multichannel mode not supported.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/wait.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>

#include <mach/dma.h>
#include <mach/mcbsp.h>

static struct omap_mcbsp mcbsp[OMAP_MAX_MCBSP_COUNT];

#define omap_mcbsp_check_valid_id(id)     (mcbsp[id].pdata && \
                              mcbsp[id].pdata->ops && \
                              mcbsp[id].pdata->ops->check && \
                              (mcbsp[id].pdata->ops->check(id) == 0))

static void omap_mcbsp_dump_reg(u8 id)
{
      dev_dbg(mcbsp[id].dev, "**** McBSP%d regs ****\n", mcbsp[id].id);
      dev_dbg(mcbsp[id].dev, "DRR2:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, DRR2));
      dev_dbg(mcbsp[id].dev, "DRR1:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, DRR1));
      dev_dbg(mcbsp[id].dev, "DXR2:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, DXR2));
      dev_dbg(mcbsp[id].dev, "DXR1:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, DXR1));
      dev_dbg(mcbsp[id].dev, "SPCR2: 0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, SPCR2));
      dev_dbg(mcbsp[id].dev, "SPCR1: 0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, SPCR1));
      dev_dbg(mcbsp[id].dev, "RCR2:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, RCR2));
      dev_dbg(mcbsp[id].dev, "RCR1:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, RCR1));
      dev_dbg(mcbsp[id].dev, "XCR2:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, XCR2));
      dev_dbg(mcbsp[id].dev, "XCR1:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, XCR1));
      dev_dbg(mcbsp[id].dev, "SRGR2: 0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, SRGR2));
      dev_dbg(mcbsp[id].dev, "SRGR1: 0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, SRGR1));
      dev_dbg(mcbsp[id].dev, "PCR0:  0x%04x\n",
                  OMAP_MCBSP_READ(mcbsp[id].io_base, PCR0));
      dev_dbg(mcbsp[id].dev, "***********************\n");
}

static irqreturn_t omap_mcbsp_tx_irq_handler(int irq, void *dev_id)
{
      struct omap_mcbsp *mcbsp_tx = dev_id;

      dev_dbg(mcbsp_tx->dev, "TX IRQ callback : 0x%x\n",
            OMAP_MCBSP_READ(mcbsp_tx->io_base, SPCR2));

      complete(&mcbsp_tx->tx_irq_completion);

      return IRQ_HANDLED;
}

static irqreturn_t omap_mcbsp_rx_irq_handler(int irq, void *dev_id)
{
      struct omap_mcbsp *mcbsp_rx = dev_id;

      dev_dbg(mcbsp_rx->dev, "RX IRQ callback : 0x%x\n",
            OMAP_MCBSP_READ(mcbsp_rx->io_base, SPCR2));

      complete(&mcbsp_rx->rx_irq_completion);

      return IRQ_HANDLED;
}

static void omap_mcbsp_tx_dma_callback(int lch, u16 ch_status, void *data)
{
      struct omap_mcbsp *mcbsp_dma_tx = data;

      dev_dbg(mcbsp_dma_tx->dev, "TX DMA callback : 0x%x\n",
            OMAP_MCBSP_READ(mcbsp_dma_tx->io_base, SPCR2));

      /* We can free the channels */
      omap_free_dma(mcbsp_dma_tx->dma_tx_lch);
      mcbsp_dma_tx->dma_tx_lch = -1;

      complete(&mcbsp_dma_tx->tx_dma_completion);
}

static void omap_mcbsp_rx_dma_callback(int lch, u16 ch_status, void *data)
{
      struct omap_mcbsp *mcbsp_dma_rx = data;

      dev_dbg(mcbsp_dma_rx->dev, "RX DMA callback : 0x%x\n",
            OMAP_MCBSP_READ(mcbsp_dma_rx->io_base, SPCR2));

      /* We can free the channels */
      omap_free_dma(mcbsp_dma_rx->dma_rx_lch);
      mcbsp_dma_rx->dma_rx_lch = -1;

      complete(&mcbsp_dma_rx->rx_dma_completion);
}

/*
 * omap_mcbsp_config simply write a config to the
 * appropriate McBSP.
 * You either call this function or set the McBSP registers
 * by yourself before calling omap_mcbsp_start().
 */
void omap_mcbsp_config(unsigned int id, const struct omap_mcbsp_reg_cfg *config)
{
      u32 io_base;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      io_base = mcbsp[id].io_base;
      dev_dbg(mcbsp[id].dev, "Configuring McBSP%d  io_base: 0x%8x\n",
                  mcbsp[id].id, io_base);

      /* We write the given config */
      OMAP_MCBSP_WRITE(io_base, SPCR2, config->spcr2);
      OMAP_MCBSP_WRITE(io_base, SPCR1, config->spcr1);
      OMAP_MCBSP_WRITE(io_base, RCR2, config->rcr2);
      OMAP_MCBSP_WRITE(io_base, RCR1, config->rcr1);
      OMAP_MCBSP_WRITE(io_base, XCR2, config->xcr2);
      OMAP_MCBSP_WRITE(io_base, XCR1, config->xcr1);
      OMAP_MCBSP_WRITE(io_base, SRGR2, config->srgr2);
      OMAP_MCBSP_WRITE(io_base, SRGR1, config->srgr1);
      OMAP_MCBSP_WRITE(io_base, MCR2, config->mcr2);
      OMAP_MCBSP_WRITE(io_base, MCR1, config->mcr1);
      OMAP_MCBSP_WRITE(io_base, PCR0, config->pcr0);
}
EXPORT_SYMBOL(omap_mcbsp_config);

/*
 * We can choose between IRQ based or polled IO.
 * This needs to be called before omap_mcbsp_request().
 */
int omap_mcbsp_set_io_type(unsigned int id, omap_mcbsp_io_type_t io_type)
{
      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      spin_lock(&mcbsp[id].lock);

      if (!mcbsp[id].free) {
            dev_err(mcbsp[id].dev, "McBSP%d is currently in use\n",
                  mcbsp[id].id);
            spin_unlock(&mcbsp[id].lock);
            return -EINVAL;
      }

      mcbsp[id].io_type = io_type;

      spin_unlock(&mcbsp[id].lock);

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_set_io_type);

int omap_mcbsp_request(unsigned int id)
{
      int err;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      if (mcbsp[id].pdata->ops->request)
            mcbsp[id].pdata->ops->request(id);

      clk_enable(mcbsp[id].clk);

      spin_lock(&mcbsp[id].lock);
      if (!mcbsp[id].free) {
            dev_err(mcbsp[id].dev, "McBSP%d is currently in use\n",
                  mcbsp[id].id);
            spin_unlock(&mcbsp[id].lock);
            return -1;
      }

      mcbsp[id].free = 0;
      spin_unlock(&mcbsp[id].lock);

      if (mcbsp[id].io_type == OMAP_MCBSP_IRQ_IO) {
            /* We need to get IRQs here */
            err = request_irq(mcbsp[id].tx_irq, omap_mcbsp_tx_irq_handler,
                              0, "McBSP", (void *) (&mcbsp[id]));
            if (err != 0) {
                  dev_err(mcbsp[id].dev, "Unable to request TX IRQ %d "
                              "for McBSP%d\n", mcbsp[id].tx_irq,
                              mcbsp[id].id);
                  return err;
            }

            init_completion(&(mcbsp[id].tx_irq_completion));

            err = request_irq(mcbsp[id].rx_irq, omap_mcbsp_rx_irq_handler,
                              0, "McBSP", (void *) (&mcbsp[id]));
            if (err != 0) {
                  dev_err(mcbsp[id].dev, "Unable to request RX IRQ %d "
                              "for McBSP%d\n", mcbsp[id].rx_irq,
                              mcbsp[id].id);
                  free_irq(mcbsp[id].tx_irq, (void *) (&mcbsp[id]));
                  return err;
            }

            init_completion(&(mcbsp[id].rx_irq_completion));
      }

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_request);

void omap_mcbsp_free(unsigned int id)
{
      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      if (mcbsp[id].pdata->ops->free)
            mcbsp[id].pdata->ops->free(id);

      clk_disable(mcbsp[id].clk);

      spin_lock(&mcbsp[id].lock);
      if (mcbsp[id].free) {
            dev_err(mcbsp[id].dev, "McBSP%d was not reserved\n",
                  mcbsp[id].id);
            spin_unlock(&mcbsp[id].lock);
            return;
      }

      mcbsp[id].free = 1;
      spin_unlock(&mcbsp[id].lock);

      if (mcbsp[id].io_type == OMAP_MCBSP_IRQ_IO) {
            /* Free IRQs */
            free_irq(mcbsp[id].rx_irq, (void *) (&mcbsp[id]));
            free_irq(mcbsp[id].tx_irq, (void *) (&mcbsp[id]));
      }
}
EXPORT_SYMBOL(omap_mcbsp_free);

/*
 * Here we start the McBSP, by enabling the sample
 * generator, both transmitter and receivers,
 * and the frame sync.
 */
void omap_mcbsp_start(unsigned int id)
{
      u32 io_base;
      u16 w;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      io_base = mcbsp[id].io_base;

      mcbsp[id].rx_word_length = (OMAP_MCBSP_READ(io_base, RCR1) >> 5) & 0x7;
      mcbsp[id].tx_word_length = (OMAP_MCBSP_READ(io_base, XCR1) >> 5) & 0x7;

      /* Start the sample generator */
      w = OMAP_MCBSP_READ(io_base, SPCR2);
      OMAP_MCBSP_WRITE(io_base, SPCR2, w | (1 << 6));

      /* Enable transmitter and receiver */
      w = OMAP_MCBSP_READ(io_base, SPCR2);
      OMAP_MCBSP_WRITE(io_base, SPCR2, w | 1);

      w = OMAP_MCBSP_READ(io_base, SPCR1);
      OMAP_MCBSP_WRITE(io_base, SPCR1, w | 1);

      udelay(100);

      /* Start frame sync */
      w = OMAP_MCBSP_READ(io_base, SPCR2);
      OMAP_MCBSP_WRITE(io_base, SPCR2, w | (1 << 7));

      /* Dump McBSP Regs */
      omap_mcbsp_dump_reg(id);
}
EXPORT_SYMBOL(omap_mcbsp_start);

void omap_mcbsp_stop(unsigned int id)
{
      u32 io_base;
      u16 w;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      io_base = mcbsp[id].io_base;

      /* Reset transmitter */
      w = OMAP_MCBSP_READ(io_base, SPCR2);
      OMAP_MCBSP_WRITE(io_base, SPCR2, w & ~(1));

      /* Reset receiver */
      w = OMAP_MCBSP_READ(io_base, SPCR1);
      OMAP_MCBSP_WRITE(io_base, SPCR1, w & ~(1));

      /* Reset the sample rate generator */
      w = OMAP_MCBSP_READ(io_base, SPCR2);
      OMAP_MCBSP_WRITE(io_base, SPCR2, w & ~(1 << 6));
}
EXPORT_SYMBOL(omap_mcbsp_stop);

/* polled mcbsp i/o operations */
int omap_mcbsp_pollwrite(unsigned int id, u16 buf)
{
      u32 base;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      base = mcbsp[id].io_base;
      writew(buf, base + OMAP_MCBSP_REG_DXR1);
      /* if frame sync error - clear the error */
      if (readw(base + OMAP_MCBSP_REG_SPCR2) & XSYNC_ERR) {
            /* clear error */
            writew(readw(base + OMAP_MCBSP_REG_SPCR2) & (~XSYNC_ERR),
                   base + OMAP_MCBSP_REG_SPCR2);
            /* resend */
            return -1;
      } else {
            /* wait for transmit confirmation */
            int attemps = 0;
            while (!(readw(base + OMAP_MCBSP_REG_SPCR2) & XRDY)) {
                  if (attemps++ > 1000) {
                        writew(readw(base + OMAP_MCBSP_REG_SPCR2) &
                               (~XRST),
                               base + OMAP_MCBSP_REG_SPCR2);
                        udelay(10);
                        writew(readw(base + OMAP_MCBSP_REG_SPCR2) |
                               (XRST),
                               base + OMAP_MCBSP_REG_SPCR2);
                        udelay(10);
                        dev_err(mcbsp[id].dev, "Could not write to"
                              " McBSP%d Register\n", mcbsp[id].id);
                        return -2;
                  }
            }
      }

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_pollwrite);

int omap_mcbsp_pollread(unsigned int id, u16 *buf)
{
      u32 base;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      base = mcbsp[id].io_base;
      /* if frame sync error - clear the error */
      if (readw(base + OMAP_MCBSP_REG_SPCR1) & RSYNC_ERR) {
            /* clear error */
            writew(readw(base + OMAP_MCBSP_REG_SPCR1) & (~RSYNC_ERR),
                   base + OMAP_MCBSP_REG_SPCR1);
            /* resend */
            return -1;
      } else {
            /* wait for recieve confirmation */
            int attemps = 0;
            while (!(readw(base + OMAP_MCBSP_REG_SPCR1) & RRDY)) {
                  if (attemps++ > 1000) {
                        writew(readw(base + OMAP_MCBSP_REG_SPCR1) &
                               (~RRST),
                               base + OMAP_MCBSP_REG_SPCR1);
                        udelay(10);
                        writew(readw(base + OMAP_MCBSP_REG_SPCR1) |
                               (RRST),
                               base + OMAP_MCBSP_REG_SPCR1);
                        udelay(10);
                        dev_err(mcbsp[id].dev, "Could not read from"
                              " McBSP%d Register\n", mcbsp[id].id);
                        return -2;
                  }
            }
      }
      *buf = readw(base + OMAP_MCBSP_REG_DRR1);

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_pollread);

/*
 * IRQ based word transmission.
 */
void omap_mcbsp_xmit_word(unsigned int id, u32 word)
{
      u32 io_base;
      omap_mcbsp_word_length word_length;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      io_base = mcbsp[id].io_base;
      word_length = mcbsp[id].tx_word_length;

      wait_for_completion(&(mcbsp[id].tx_irq_completion));

      if (word_length > OMAP_MCBSP_WORD_16)
            OMAP_MCBSP_WRITE(io_base, DXR2, word >> 16);
      OMAP_MCBSP_WRITE(io_base, DXR1, word & 0xffff);
}
EXPORT_SYMBOL(omap_mcbsp_xmit_word);

u32 omap_mcbsp_recv_word(unsigned int id)
{
      u32 io_base;
      u16 word_lsb, word_msb = 0;
      omap_mcbsp_word_length word_length;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      word_length = mcbsp[id].rx_word_length;
      io_base = mcbsp[id].io_base;

      wait_for_completion(&(mcbsp[id].rx_irq_completion));

      if (word_length > OMAP_MCBSP_WORD_16)
            word_msb = OMAP_MCBSP_READ(io_base, DRR2);
      word_lsb = OMAP_MCBSP_READ(io_base, DRR1);

      return (word_lsb | (word_msb << 16));
}
EXPORT_SYMBOL(omap_mcbsp_recv_word);

int omap_mcbsp_spi_master_xmit_word_poll(unsigned int id, u32 word)
{
      u32 io_base;
      omap_mcbsp_word_length tx_word_length;
      omap_mcbsp_word_length rx_word_length;
      u16 spcr2, spcr1, attempts = 0, word_lsb, word_msb = 0;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      io_base = mcbsp[id].io_base;
      tx_word_length = mcbsp[id].tx_word_length;
      rx_word_length = mcbsp[id].rx_word_length;

      if (tx_word_length != rx_word_length)
            return -EINVAL;

      /* First we wait for the transmitter to be ready */
      spcr2 = OMAP_MCBSP_READ(io_base, SPCR2);
      while (!(spcr2 & XRDY)) {
            spcr2 = OMAP_MCBSP_READ(io_base, SPCR2);
            if (attempts++ > 1000) {
                  /* We must reset the transmitter */
                  OMAP_MCBSP_WRITE(io_base, SPCR2, spcr2 & (~XRST));
                  udelay(10);
                  OMAP_MCBSP_WRITE(io_base, SPCR2, spcr2 | XRST);
                  udelay(10);
                  dev_err(mcbsp[id].dev, "McBSP%d transmitter not "
                        "ready\n", mcbsp[id].id);
                  return -EAGAIN;
            }
      }

      /* Now we can push the data */
      if (tx_word_length > OMAP_MCBSP_WORD_16)
            OMAP_MCBSP_WRITE(io_base, DXR2, word >> 16);
      OMAP_MCBSP_WRITE(io_base, DXR1, word & 0xffff);

      /* We wait for the receiver to be ready */
      spcr1 = OMAP_MCBSP_READ(io_base, SPCR1);
      while (!(spcr1 & RRDY)) {
            spcr1 = OMAP_MCBSP_READ(io_base, SPCR1);
            if (attempts++ > 1000) {
                  /* We must reset the receiver */
                  OMAP_MCBSP_WRITE(io_base, SPCR1, spcr1 & (~RRST));
                  udelay(10);
                  OMAP_MCBSP_WRITE(io_base, SPCR1, spcr1 | RRST);
                  udelay(10);
                  dev_err(mcbsp[id].dev, "McBSP%d receiver not "
                        "ready\n", mcbsp[id].id);
                  return -EAGAIN;
            }
      }

      /* Receiver is ready, let's read the dummy data */
      if (rx_word_length > OMAP_MCBSP_WORD_16)
            word_msb = OMAP_MCBSP_READ(io_base, DRR2);
      word_lsb = OMAP_MCBSP_READ(io_base, DRR1);

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_spi_master_xmit_word_poll);

int omap_mcbsp_spi_master_recv_word_poll(unsigned int id, u32 *word)
{
      u32 io_base, clock_word = 0;
      omap_mcbsp_word_length tx_word_length;
      omap_mcbsp_word_length rx_word_length;
      u16 spcr2, spcr1, attempts = 0, word_lsb, word_msb = 0;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      io_base = mcbsp[id].io_base;
      tx_word_length = mcbsp[id].tx_word_length;
      rx_word_length = mcbsp[id].rx_word_length;

      if (tx_word_length != rx_word_length)
            return -EINVAL;

      /* First we wait for the transmitter to be ready */
      spcr2 = OMAP_MCBSP_READ(io_base, SPCR2);
      while (!(spcr2 & XRDY)) {
            spcr2 = OMAP_MCBSP_READ(io_base, SPCR2);
            if (attempts++ > 1000) {
                  /* We must reset the transmitter */
                  OMAP_MCBSP_WRITE(io_base, SPCR2, spcr2 & (~XRST));
                  udelay(10);
                  OMAP_MCBSP_WRITE(io_base, SPCR2, spcr2 | XRST);
                  udelay(10);
                  dev_err(mcbsp[id].dev, "McBSP%d transmitter not "
                        "ready\n", mcbsp[id].id);
                  return -EAGAIN;
            }
      }

      /* We first need to enable the bus clock */
      if (tx_word_length > OMAP_MCBSP_WORD_16)
            OMAP_MCBSP_WRITE(io_base, DXR2, clock_word >> 16);
      OMAP_MCBSP_WRITE(io_base, DXR1, clock_word & 0xffff);

      /* We wait for the receiver to be ready */
      spcr1 = OMAP_MCBSP_READ(io_base, SPCR1);
      while (!(spcr1 & RRDY)) {
            spcr1 = OMAP_MCBSP_READ(io_base, SPCR1);
            if (attempts++ > 1000) {
                  /* We must reset the receiver */
                  OMAP_MCBSP_WRITE(io_base, SPCR1, spcr1 & (~RRST));
                  udelay(10);
                  OMAP_MCBSP_WRITE(io_base, SPCR1, spcr1 | RRST);
                  udelay(10);
                  dev_err(mcbsp[id].dev, "McBSP%d receiver not "
                        "ready\n", mcbsp[id].id);
                  return -EAGAIN;
            }
      }

      /* Receiver is ready, there is something for us */
      if (rx_word_length > OMAP_MCBSP_WORD_16)
            word_msb = OMAP_MCBSP_READ(io_base, DRR2);
      word_lsb = OMAP_MCBSP_READ(io_base, DRR1);

      word[0] = (word_lsb | (word_msb << 16));

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_spi_master_recv_word_poll);

/*
 * Simple DMA based buffer rx/tx routines.
 * Nothing fancy, just a single buffer tx/rx through DMA.
 * The DMA resources are released once the transfer is done.
 * For anything fancier, you should use your own customized DMA
 * routines and callbacks.
 */
int omap_mcbsp_xmit_buffer(unsigned int id, dma_addr_t buffer,
                        unsigned int length)
{
      int dma_tx_ch;
      int src_port = 0;
      int dest_port = 0;
      int sync_dev = 0;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      if (omap_request_dma(mcbsp[id].dma_tx_sync, "McBSP TX",
                        omap_mcbsp_tx_dma_callback,
                        &mcbsp[id],
                        &dma_tx_ch)) {
            dev_err(mcbsp[id].dev, " Unable to request DMA channel for "
                        "McBSP%d TX. Trying IRQ based TX\n",
                        mcbsp[id].id);
            return -EAGAIN;
      }
      mcbsp[id].dma_tx_lch = dma_tx_ch;

      dev_err(mcbsp[id].dev, "McBSP%d TX DMA on channel %d\n", mcbsp[id].id,
            dma_tx_ch);

      init_completion(&(mcbsp[id].tx_dma_completion));

      if (cpu_class_is_omap1()) {
            src_port = OMAP_DMA_PORT_TIPB;
            dest_port = OMAP_DMA_PORT_EMIFF;
      }
      if (cpu_class_is_omap2())
            sync_dev = mcbsp[id].dma_tx_sync;

      omap_set_dma_transfer_params(mcbsp[id].dma_tx_lch,
                             OMAP_DMA_DATA_TYPE_S16,
                             length >> 1, 1,
                             OMAP_DMA_SYNC_ELEMENT,
       sync_dev, 0);

      omap_set_dma_dest_params(mcbsp[id].dma_tx_lch,
                         src_port,
                         OMAP_DMA_AMODE_CONSTANT,
                         mcbsp[id].phys_base + OMAP_MCBSP_REG_DXR1,
                         0, 0);

      omap_set_dma_src_params(mcbsp[id].dma_tx_lch,
                        dest_port,
                        OMAP_DMA_AMODE_POST_INC,
                        buffer,
                        0, 0);

      omap_start_dma(mcbsp[id].dma_tx_lch);
      wait_for_completion(&(mcbsp[id].tx_dma_completion));

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_xmit_buffer);

int omap_mcbsp_recv_buffer(unsigned int id, dma_addr_t buffer,
                        unsigned int length)
{
      int dma_rx_ch;
      int src_port = 0;
      int dest_port = 0;
      int sync_dev = 0;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return -ENODEV;
      }

      if (omap_request_dma(mcbsp[id].dma_rx_sync, "McBSP RX",
                        omap_mcbsp_rx_dma_callback,
                        &mcbsp[id],
                        &dma_rx_ch)) {
            dev_err(mcbsp[id].dev, "Unable to request DMA channel for "
                        "McBSP%d RX. Trying IRQ based RX\n",
                        mcbsp[id].id);
            return -EAGAIN;
      }
      mcbsp[id].dma_rx_lch = dma_rx_ch;

      dev_err(mcbsp[id].dev, "McBSP%d RX DMA on channel %d\n", mcbsp[id].id,
            dma_rx_ch);

      init_completion(&(mcbsp[id].rx_dma_completion));

      if (cpu_class_is_omap1()) {
            src_port = OMAP_DMA_PORT_TIPB;
            dest_port = OMAP_DMA_PORT_EMIFF;
      }
      if (cpu_class_is_omap2())
            sync_dev = mcbsp[id].dma_rx_sync;

      omap_set_dma_transfer_params(mcbsp[id].dma_rx_lch,
                              OMAP_DMA_DATA_TYPE_S16,
                              length >> 1, 1,
                              OMAP_DMA_SYNC_ELEMENT,
                              sync_dev, 0);

      omap_set_dma_src_params(mcbsp[id].dma_rx_lch,
                        src_port,
                        OMAP_DMA_AMODE_CONSTANT,
                        mcbsp[id].phys_base + OMAP_MCBSP_REG_DRR1,
                        0, 0);

      omap_set_dma_dest_params(mcbsp[id].dma_rx_lch,
                              dest_port,
                              OMAP_DMA_AMODE_POST_INC,
                              buffer,
                              0, 0);

      omap_start_dma(mcbsp[id].dma_rx_lch);
      wait_for_completion(&(mcbsp[id].rx_dma_completion));

      return 0;
}
EXPORT_SYMBOL(omap_mcbsp_recv_buffer);

/*
 * SPI wrapper.
 * Since SPI setup is much simpler than the generic McBSP one,
 * this wrapper just need an omap_mcbsp_spi_cfg structure as an input.
 * Once this is done, you can call omap_mcbsp_start().
 */
void omap_mcbsp_set_spi_mode(unsigned int id,
                        const struct omap_mcbsp_spi_cfg *spi_cfg)
{
      struct omap_mcbsp_reg_cfg mcbsp_cfg;

      if (!omap_mcbsp_check_valid_id(id)) {
            printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
            return;
      }

      memset(&mcbsp_cfg, 0, sizeof(struct omap_mcbsp_reg_cfg));

      /* SPI has only one frame */
      mcbsp_cfg.rcr1 |= (RWDLEN1(spi_cfg->word_length) | RFRLEN1(0));
      mcbsp_cfg.xcr1 |= (XWDLEN1(spi_cfg->word_length) | XFRLEN1(0));

      /* Clock stop mode */
      if (spi_cfg->clk_stp_mode == OMAP_MCBSP_CLK_STP_MODE_NO_DELAY)
            mcbsp_cfg.spcr1 |= (1 << 12);
      else
            mcbsp_cfg.spcr1 |= (3 << 11);

      /* Set clock parities */
      if (spi_cfg->rx_clock_polarity == OMAP_MCBSP_CLK_RISING)
            mcbsp_cfg.pcr0 |= CLKRP;
      else
            mcbsp_cfg.pcr0 &= ~CLKRP;

      if (spi_cfg->tx_clock_polarity == OMAP_MCBSP_CLK_RISING)
            mcbsp_cfg.pcr0 &= ~CLKXP;
      else
            mcbsp_cfg.pcr0 |= CLKXP;

      /* Set SCLKME to 0 and CLKSM to 1 */
      mcbsp_cfg.pcr0 &= ~SCLKME;
      mcbsp_cfg.srgr2 |= CLKSM;

      /* Set FSXP */
      if (spi_cfg->fsx_polarity == OMAP_MCBSP_FS_ACTIVE_HIGH)
            mcbsp_cfg.pcr0 &= ~FSXP;
      else
            mcbsp_cfg.pcr0 |= FSXP;

      if (spi_cfg->spi_mode == OMAP_MCBSP_SPI_MASTER) {
            mcbsp_cfg.pcr0 |= CLKXM;
            mcbsp_cfg.srgr1 |= CLKGDV(spi_cfg->clk_div - 1);
            mcbsp_cfg.pcr0 |= FSXM;
            mcbsp_cfg.srgr2 &= ~FSGM;
            mcbsp_cfg.xcr2 |= XDATDLY(1);
            mcbsp_cfg.rcr2 |= RDATDLY(1);
      } else {
            mcbsp_cfg.pcr0 &= ~CLKXM;
            mcbsp_cfg.srgr1 |= CLKGDV(1);
            mcbsp_cfg.pcr0 &= ~FSXM;
            mcbsp_cfg.xcr2 &= ~XDATDLY(3);
            mcbsp_cfg.rcr2 &= ~RDATDLY(3);
      }

      mcbsp_cfg.xcr2 &= ~XPHASE;
      mcbsp_cfg.rcr2 &= ~RPHASE;

      omap_mcbsp_config(id, &mcbsp_cfg);
}
EXPORT_SYMBOL(omap_mcbsp_set_spi_mode);

/*
 * McBSP1 and McBSP3 are directly mapped on 1610 and 1510.
 * 730 has only 2 McBSP, and both of them are MPU peripherals.
 */
static int __init omap_mcbsp_probe(struct platform_device *pdev)
{
      struct omap_mcbsp_platform_data *pdata = pdev->dev.platform_data;
      int id = pdev->id - 1;
      int ret = 0;

      if (!pdata) {
            dev_err(&pdev->dev, "McBSP device initialized without"
                        "platform data\n");
            ret = -EINVAL;
            goto exit;
      }

      dev_dbg(&pdev->dev, "Initializing OMAP McBSP (%d).\n", pdev->id);

      if (id >= OMAP_MAX_MCBSP_COUNT) {
            dev_err(&pdev->dev, "Invalid McBSP device id (%d)\n", id);
            ret = -EINVAL;
            goto exit;
      }

      spin_lock_init(&mcbsp[id].lock);
      mcbsp[id].id = id + 1;
      mcbsp[id].free = 1;
      mcbsp[id].dma_tx_lch = -1;
      mcbsp[id].dma_rx_lch = -1;

      mcbsp[id].phys_base = pdata->phys_base;
      mcbsp[id].io_base = pdata->virt_base;
      /* Default I/O is IRQ based */
      mcbsp[id].io_type = OMAP_MCBSP_IRQ_IO;
      mcbsp[id].tx_irq = pdata->tx_irq;
      mcbsp[id].rx_irq = pdata->rx_irq;
      mcbsp[id].dma_rx_sync = pdata->dma_rx_sync;
      mcbsp[id].dma_tx_sync = pdata->dma_tx_sync;

      if (pdata->clk_name)
            mcbsp[id].clk = clk_get(&pdev->dev, pdata->clk_name);
      if (IS_ERR(mcbsp[id].clk)) {
            mcbsp[id].free = 0;
            dev_err(&pdev->dev,
                  "Invalid clock configuration for McBSP%d.\n",
                  mcbsp[id].id);
            ret = -EINVAL;
            goto exit;
      }

      mcbsp[id].pdata = pdata;
      mcbsp[id].dev = &pdev->dev;
      platform_set_drvdata(pdev, &mcbsp[id]);

exit:
      return ret;
}

static int omap_mcbsp_remove(struct platform_device *pdev)
{
      struct omap_mcbsp *mcbsp = platform_get_drvdata(pdev);

      platform_set_drvdata(pdev, NULL);
      if (mcbsp) {

            if (mcbsp->pdata && mcbsp->pdata->ops &&
                        mcbsp->pdata->ops->free)
                  mcbsp->pdata->ops->free(mcbsp->id);

            clk_disable(mcbsp->clk);
            clk_put(mcbsp->clk);

            mcbsp->clk = NULL;
            mcbsp->free = 0;
            mcbsp->dev = NULL;
      }

      return 0;
}

static struct platform_driver omap_mcbsp_driver = {
      .probe            = omap_mcbsp_probe,
      .remove           = omap_mcbsp_remove,
      .driver           = {
            .name = "omap-mcbsp",
      },
};

int __init omap_mcbsp_init(void)
{
      /* Register the McBSP driver */
      return platform_driver_register(&omap_mcbsp_driver);
}


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