video: sh_mobile_lcdcfb suspend/resume support

This patch adds suspend/resume support to the LCDC
driver for SuperH Mobile - sh_mobile_lcdcfb.

We simply stop hardware on suspend and start it again
on resume. For RGB panels this is trivial, but for SYS
panels in deferred io mode this becomes a bit more
difficult - we need to wait for a frame end interrupt
to make sure the clocks are balanced before stopping
the actual hardware.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Magnus Damm 2009-03-13 15:36:55 +00:00 committed by Paul Mundt
parent 93356d0747
commit 2feb075a33

View file

@ -33,6 +33,8 @@ struct sh_mobile_lcdc_chan {
struct fb_info info;
dma_addr_t dma_handle;
struct fb_deferred_io defio;
unsigned long frame_end;
wait_queue_head_t frame_end_wait;
};
struct sh_mobile_lcdc_priv {
@ -226,7 +228,10 @@ static void sh_mobile_lcdc_deferred_io_touch(struct fb_info *info)
static irqreturn_t sh_mobile_lcdc_irq(int irq, void *data)
{
struct sh_mobile_lcdc_priv *priv = data;
struct sh_mobile_lcdc_chan *ch;
unsigned long tmp;
int is_sub;
int k;
/* acknowledge interrupt */
tmp = lcdc_read(priv, _LDINTR);
@ -234,8 +239,24 @@ static irqreturn_t sh_mobile_lcdc_irq(int irq, void *data)
tmp |= 0x000000ff ^ LDINTR_FS; /* status in low 8 */
lcdc_write(priv, _LDINTR, tmp);
/* disable clocks */
sh_mobile_lcdc_clk_off(priv);
/* figure out if this interrupt is for main or sub lcd */
is_sub = (lcdc_read(priv, _LDSR) & (1 << 10)) ? 1 : 0;
/* wake up channel and disable clocks*/
for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
ch = &priv->ch[k];
if (!ch->enabled)
continue;
if (is_sub == lcdc_chan_is_sublcd(ch)) {
ch->frame_end = 1;
wake_up(&ch->frame_end_wait);
sh_mobile_lcdc_clk_off(priv);
}
}
return IRQ_HANDLED;
}
@ -448,18 +469,27 @@ static void sh_mobile_lcdc_stop(struct sh_mobile_lcdc_priv *priv)
struct sh_mobile_lcdc_board_cfg *board_cfg;
int k;
/* tell the board code to disable the panel */
/* clean up deferred io and ask board code to disable panel */
for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
ch = &priv->ch[k];
/* deferred io mode:
* flush frame, and wait for frame end interrupt
* clean up deferred io and enable clock
*/
if (ch->info.fbdefio) {
ch->frame_end = 0;
schedule_delayed_work(&ch->info.deferred_work, 0);
wait_event(ch->frame_end_wait, ch->frame_end);
fb_deferred_io_cleanup(&ch->info);
ch->info.fbdefio = NULL;
sh_mobile_lcdc_clk_on(priv);
}
board_cfg = &ch->cfg.board_cfg;
if (board_cfg->display_off)
board_cfg->display_off(board_cfg->board_data);
/* cleanup deferred io if enabled */
if (ch->info.fbdefio) {
fb_deferred_io_cleanup(&ch->info);
ch->info.fbdefio = NULL;
}
}
/* stop the lcdc */
@ -652,6 +682,26 @@ static int sh_mobile_lcdc_set_bpp(struct fb_var_screeninfo *var, int bpp)
return 0;
}
static int sh_mobile_lcdc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
sh_mobile_lcdc_stop(platform_get_drvdata(pdev));
return 0;
}
static int sh_mobile_lcdc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
return sh_mobile_lcdc_start(platform_get_drvdata(pdev));
}
static struct dev_pm_ops sh_mobile_lcdc_dev_pm_ops = {
.suspend = sh_mobile_lcdc_suspend,
.resume = sh_mobile_lcdc_resume,
};
static int sh_mobile_lcdc_remove(struct platform_device *pdev);
static int __init sh_mobile_lcdc_probe(struct platform_device *pdev)
@ -707,6 +757,7 @@ static int __init sh_mobile_lcdc_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "unsupported interface type\n");
goto err1;
}
init_waitqueue_head(&priv->ch[i].frame_end_wait);
switch (pdata->ch[i].chan) {
case LCDC_CHAN_MAINLCD:
@ -860,6 +911,7 @@ static struct platform_driver sh_mobile_lcdc_driver = {
.driver = {
.name = "sh_mobile_lcdc_fb",
.owner = THIS_MODULE,
.pm = &sh_mobile_lcdc_dev_pm_ops,
},
.probe = sh_mobile_lcdc_probe,
.remove = sh_mobile_lcdc_remove,