static int bfin_lq035_fb_open(struct fb_info *info, int user)
{
unsigned long flags;
spin_lock_irqsave(&bfin_lq035_lock, flags);
lq035_open_cnt++;
spin_unlock_irqrestore(&bfin_lq035_lock, flags);
if (lq035_open_cnt <= 1) {
bfin_write_PPI_CONTROL(0);
SSYNC();
set_vcomm();
config_dma();
config_ppi();
/* start dma */
enable_dma(CH_PPI);
SSYNC();
bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() | PORT_EN);
SSYNC();
if (!t_conf_done) {
config_timers();
start_timers();
}
/* gpio_set_value(MOD,1); */
}
return 0;
}
static int __init ppi_adc_init(void) {
int ret;
ret = dma_init();
if(ret) {
return ret;
}
ret = ppi_init();
if(ret) {
dma_close();
return ret;
}
ret = device_init();
if(ret) {
ppi_close();
dma_close();
return ret;
}
/* Disable everything */
disable_dma(CH_PPI);
bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() & (~PORT_EN));
SSYNC();
return 0;
}
static int ppi_chr_release(struct inode* i, struct file* filp) {
/* Disable PPI */
bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() & (~PORT_EN));
/* Disable DMA */
disable_dma(CH_PPI);
return 0;
}
static int ppi_chr_open(struct inode* i, struct file* filp) {
/* Reset global values */
current_buffer_index = 0;
current_buffer_pointer = 0;
/* Enable DMA */
enable_dma(CH_PPI);
/* Enable PPI */
bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() | PORT_EN);
return 0;
}
/*
* FUNCTION NAME: ppi_read
*
* INPUTS/OUTPUTS:
* in_filp - Description of openned file.
* in_count - how many bytes user wants to get.
* out_buf - data would be write to this address.
*
* RETURN
* positive number: bytes read back
* -EINVIL When word size is set to 16, reading odd bytes.
* -EAGAIN When reading mode is set to non block and there is no rx data.
*
* FUNCTION(S) CALLED:
*
* GLOBAL VARIABLES REFERENCED: ppiinfo
*
* GLOBAL VARIABLES MODIFIED: NIL
*
* DESCRIPTION: It is invoked when user call 'read' system call
* to read from system.
*
* CAUTION:
*/
static ssize_t ppi_read(struct file *filp, char *buf, size_t count,
loff_t * pos)
{
int ierr;
ppi_device_t *pdev = filp->private_data;
pr_debug("ppi_read:\n");
if (count <= 0)
return 0;
pdev->done = 0;
/* Invalidate allocated memory in Data Cache */
blackfin_dcache_invalidate_range((u_long) buf, (u_long) (buf + count));
pr_debug("ppi_read: blackfin_dcache_invalidate_range : DONE\n");
/* configure ppi port for DMA RX */
set_dma_config(CH_PPI, pdev->dma_config);
set_dma_start_addr(CH_PPI, (u_long) buf);
set_dma_x_count(CH_PPI, pdev->pixel_per_line / 2); // Div 2 because of 16-bit packing
set_dma_y_count(CH_PPI, pdev->lines_per_frame);
set_dma_y_modify(CH_PPI, 2);
if (pdev->bpp > 8 || pdev->dma_config & WDSIZE_16)
set_dma_x_modify(CH_PPI, 2);
else
set_dma_x_modify(CH_PPI, 1);
pr_debug("ppi_read: SETUP DMA : DONE\n");
enable_dma(CH_PPI);
/* Enable PPI */
bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() | PORT_EN);
SSYNC();
if (pdev->ppi_trigger_gpio > NO_TRIGGER) {
gpio_set_value(pdev->ppi_trigger_gpio, 1);
udelay(1);
gpio_set_value(pdev->ppi_trigger_gpio, 0);
}
pr_debug("ppi_read: PPI ENABLED : DONE\n");
/* Wait for data available */
if (1) {
if (pdev->nonblock)
return -EAGAIN;
else {
pr_debug("PPI wait_event_interruptible\n");
ierr =
wait_event_interruptible(*(pdev->rx_avail),
pdev->done);
if (ierr) {
/* waiting is broken by a signal */
pr_debug("PPI wait_event_interruptible ierr\n");
return ierr;
}
}
}
pr_debug("PPI wait_event_interruptible done\n");
disable_dma(CH_PPI);
pr_debug("ppi_read: return\n");
return count;
}
