/*
* Start transmitting data through a McBSP interface
* id : McBSP interface ID
* cbdata : User data to be returned with callback
* buf_start_addr : The source address [This should be physical address]
* buf_size : Buffer size
*/
int omap2_mcbsp_send_data(unsigned int id, void *cbdata,
dma_addr_t buf_start_addr, u32 buf_size)
{
struct omap_mcbsp *mcbsp;
void __iomem *io_base;
u8 enable_tx = 0;
int e_count = 0;
int f_count = 0;
if (!omap_mcbsp_check_valid_id(id)) {
printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
return -ENODEV;
}
mcbsp = id_to_mcbsp_ptr(id);
io_base = mcbsp->io_base;
mcbsp->tx_cb_arg = cbdata;
/* Auto RRST handling logic - disable the Reciever before 1st dma */
if ((mcbsp->auto_reset & OMAP_MCBSP_AUTO_XRST) &&
(omap_dma_chain_status(mcbsp->dma_tx_lch)
== OMAP_DMA_CHAIN_INACTIVE)) {
OMAP_MCBSP_WRITE(mcbsp, SPCR2,
OMAP_MCBSP_READ(mcbsp, SPCR2) & (~XRST));
enable_tx = 1;
}
/*
* for skip_first and second, we need to set e_count =2, and
* f_count = number of frames = number of elements/e_count
*/
e_count = (buf_size / mcbsp->tx_word_length);
if (mcbsp->txskip_alt != OMAP_MCBSP_SKIP_NONE) {
/*
* number of frames = total number of elements/element count,
* However, with double indexing for data transfers, double I
* the number of elements need to be transmitted
*/
f_count = e_count;
e_count = 2;
} else {
f_count = 1;
}
/*
* If the DMA is to be configured to skip the first byte, we need
* to jump backwards, so we need to move one chunk forward and ask
* dma if we dont want the client driver knowing abt this.
*/
if (mcbsp->txskip_alt == OMAP_MCBSP_SKIP_FIRST)
buf_start_addr += mcbsp->tx_word_length;
if (omap_dma_chain_a_transfer(mcbsp->dma_tx_lch,
buf_start_addr, mcbsp->phys_base + OMAP_MCBSP_REG_DXR,
e_count, f_count, mcbsp) < 0)
return -EINVAL;
if (mcbsp->tx_dma_chain_state == 0) {
if (mcbsp->interface_mode == OMAP_MCBSP_MASTER)
omap2_mcbsp_set_srg_fsg(id, OMAP_MCBSP_ENABLE_FSG_SRG);
if (omap_start_dma_chain_transfers(mcbsp->dma_tx_lch) < 0)
return -EINVAL;
mcbsp->tx_dma_chain_state = 1;
}
/* Auto XRST handling logic - Enable the Reciever after 1st dma */
if (enable_tx &&
(omap_dma_chain_status(mcbsp->dma_tx_lch)
== OMAP_DMA_CHAIN_ACTIVE))
OMAP_MCBSP_WRITE(mcbsp, SPCR2,
OMAP_MCBSP_READ(mcbsp, SPCR2) | XRST);
return 0;
}
int omap2_mcbsp_receive_data(unsigned int id, void *cbdata,
dma_addr_t buf_start_addr, u32 buf_size)
{
struct omap_mcbsp *mcbsp;
void __iomem *io_base;
int enable_rx = 0;
int e_count = 0;
int f_count = 0;
if (!omap_mcbsp_check_valid_id(id)) {
printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
return -ENODEV;
}
mcbsp = id_to_mcbsp_ptr(id);
io_base = mcbsp->io_base;
mcbsp->rx_cb_arg = cbdata;
/* Auto RRST handling logic - disable the Reciever before 1st dma */
if ((mcbsp->auto_reset & OMAP_MCBSP_AUTO_RRST) &&
(omap_dma_chain_status(mcbsp->dma_rx_lch)
== OMAP_DMA_CHAIN_INACTIVE)) {
OMAP_MCBSP_WRITE(io_base, SPCR1,
OMAP_MCBSP_READ(io_base, SPCR1) & (~RRST));
enable_rx = 1;
}
/*
* for skip_first and second, we need to set e_count =2,
* and f_count = number of frames = number of elements/e_count
*/
e_count = (buf_size / mcbsp->rx_word_length);
if (mcbsp->rxskip_alt != OMAP_MCBSP_SKIP_NONE) {
/*
* since the number of frames = total number of elements/element
* count, However, with double indexing for data transfers,
* double the number of elements need to be transmitted
*/
f_count = e_count;
e_count = 2;
} else {
f_count = 1;
}
/*
* If the DMA is to be configured to skip the first byte, we need
* to jump backwards, so we need to move one chunk forward and
* ask dma if we dont want the client driver knowing abt this.
*/
if (mcbsp->rxskip_alt == OMAP_MCBSP_SKIP_FIRST)
buf_start_addr += mcbsp->rx_word_length;
if (omap_dma_chain_a_transfer(mcbsp->dma_rx_lch,
mcbsp->phys_base + OMAP_MCBSP_REG_DRR, buf_start_addr,
e_count, f_count, mcbsp) < 0) {
printk(KERN_ERR " Buffer chaining failed \n");
return -EINVAL;
}
if (mcbsp->rx_dma_chain_state == 0) {
if (omap_start_dma_chain_transfers(mcbsp->dma_rx_lch) < 0)
return -EINVAL;
mcbsp->rx_dma_chain_state = 1;
}
/* Auto RRST handling logic - Enable the Reciever after 1st dma */
if (enable_rx &&
(omap_dma_chain_status(mcbsp->dma_rx_lch)
== OMAP_DMA_CHAIN_ACTIVE))
OMAP_MCBSP_WRITE(io_base, SPCR1,
OMAP_MCBSP_READ(io_base, SPCR1) | RRST);
return 0;
}