void lcd_init_device(void)
{
semaphore_init(&g_wait_sema, 1, 0);
/* I'm not really sure this pin is related to power, it does not seem to do anything */
imx233_pinctrl_acquire(1, 8, "lcd_power");
imx233_pinctrl_acquire(1, 9, "lcd_spi_sdo");
imx233_pinctrl_acquire(1, 10, "lcd_spi_scl");
imx233_pinctrl_acquire(1, 11, "lcd_spi_cs");
imx233_pinctrl_set_function(1, 9, PINCTRL_FUNCTION_GPIO);
imx233_pinctrl_set_function(1, 10, PINCTRL_FUNCTION_GPIO);
imx233_pinctrl_set_function(1, 11, PINCTRL_FUNCTION_GPIO);
imx233_pinctrl_set_function(1, 8, PINCTRL_FUNCTION_GPIO);
imx233_pinctrl_enable_gpio(1, 8, true);
/** lcd is 320x240, data bus is 8-bit, depth is 24-bit so we need 3clk/pix
* by running PIX clock at 24MHz we can sustain ~100 fps */
imx233_clkctrl_enable(CLK_PIX, false);
imx233_clkctrl_set_div(CLK_PIX, 2);
imx233_clkctrl_set_bypass(CLK_PIX, true); /* use XTAL */
imx233_clkctrl_enable(CLK_PIX, true);
imx233_lcdif_init();
imx233_lcdif_setup_dotclk_pins(8, false);
imx233_lcdif_set_word_length(8);
imx233_lcdif_set_underflow_cb(&lcd_underflow);
imx233_lcdif_enable_underflow_irq(true);
imx233_dma_clkgate_channel(APB_LCDIF, true);
imx233_dma_reset_channel(APB_LCDIF);
/** Datasheet states:
* 257H >= VBP >= 3H, VBP > VLW, VFP >= 1H
* 1533clk >= HBP >= 24clk, HBP > HLW, HFP >= 4clk
*
* Take VLW=1H, VBP=3H, VFP=1H, HLW=8, HBP=24, HFP=4
* Take 3clk/pix because we send 24-bit/pix with 8-bit data bus
* Keep consistent with register setting in lcd_init_seq
*/
imx233_lcdif_setup_dotclk_ex(/*v_pulse_width*/1, /*v_back_porch*/3,
/*v_front_porch*/1, /*h_pulse_width*/8, /*h_back_porch*/24,
/*h_front_porch*/4, LCD_WIDTH, LCD_HEIGHT, /*clk_per_pix*/3,
/*enable_present*/false);
imx233_lcdif_set_byte_packing_format(0xf);
imx233_lcdif_enable_sync_signals(true); // we need frame signals during init
// setup dma
unsigned size = IMX233_FRAMEBUFFER_SIZE;
uint8_t *frame_p = FRAME;
for(int i = 0; i < NR_CMDS; i++)
{
unsigned xfer = MIN(IMX233_MAX_SINGLE_DMA_XFER_SIZE, size);
lcdif_dma[i].dma.next = &lcdif_dma[(i + 1) % NR_CMDS].dma;
lcdif_dma[i].dma.cmd = BF_OR3(APB_CHx_CMD, CHAIN(1),
COMMAND(BV_APB_CHx_CMD_COMMAND__READ), XFER_COUNT(xfer));
lcdif_dma[i].dma.buffer = frame_p;
size -= xfer;
frame_p += xfer;
}
// first transfer: enable run, dotclk and so on
lcdif_dma[0].dma.cmd |= BF_OR1(APB_CHx_CMD, CMDWORDS(1));
lcdif_dma[0].ctrl = BF_OR4(LCDIF_CTRL, BYPASS_COUNT(1), DOTCLK_MODE(1),
RUN(1), WORD_LENGTH(1));
// enable
lcd_enable(true);
}
void lcd_enable(bool enable)
{
if(lcd_on == enable)
return;
lcd_on = enable;
if(lcd_on)
{
// enable spi
spi_enable(true);
// reset
imx233_lcdif_reset_lcd(true);
imx233_lcdif_reset_lcd(false);
mdelay(1);
imx233_lcdif_reset_lcd(true);
mdelay(1);
// "power" on
lcd_power(true);
// setup registers
imx233_lcdif_enable_sync_signals(true); // we need frame signals during init
lcd_power_seq();
lcd_init_seq();
lcd_display_on_seq();
imx233_dma_reset_channel(APB_LCDIF);
imx233_dma_start_command(APB_LCDIF, &lcdif_dma[0].dma);
BF_SET(LCDIF_CTRL, DOTCLK_MODE);
BF_SET(LCDIF_CTRL, RUN);
}
else
{
// power down
lcd_display_off_seq();
lcd_power(false);
// stop lcdif
BF_CLR(LCDIF_CTRL, DOTCLK_MODE);
// disable spi
spi_enable(false);
}
}
