diff options
| author | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2011-07-13 14:13:47 +0400 |
|---|---|---|
| committer | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2011-08-19 10:22:38 +0400 |
| commit | dc48665fae5aa360e80dfdb2d6cab4fa58b27ee4 (patch) | |
| tree | ea56c195386fc5b997961b033d7868e0c0c8a1bc /drivers/video/sh_mobile_lcdcfb.c | |
| parent | ce1c0b0873bf4e970970a49612105cf6c36d81e3 (diff) | |
| download | linux-dc48665fae5aa360e80dfdb2d6cab4fa58b27ee4.tar.xz | |
fbdev: sh_mobile_lcdc: Don't acknowlege interrupts unintentionally
The LDINTR register caries both interrupt enable and interrupt status
bits. When setting or clearing interrupt enable bits, write all status
bits to 1 to avoid acknowledging interrupts by mistake.
When acknowledging interrupts, write 1 to all non-triggered interrupt
bits to avoid losing interrupts.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Diffstat (limited to 'drivers/video/sh_mobile_lcdcfb.c')
| -rw-r--r-- | drivers/video/sh_mobile_lcdcfb.c | 20 |
1 files changed, 8 insertions, 12 deletions
diff --git a/drivers/video/sh_mobile_lcdcfb.c b/drivers/video/sh_mobile_lcdcfb.c index 84504d574986..99656f593de4 100644 --- a/drivers/video/sh_mobile_lcdcfb.c +++ b/drivers/video/sh_mobile_lcdcfb.c @@ -318,19 +318,13 @@ 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; unsigned long ldintr; int is_sub; int k; - /* acknowledge interrupt */ - ldintr = tmp = lcdc_read(priv, _LDINTR); - /* - * disable further VSYNC End IRQs, preserve all other enabled IRQs, - * write 0 to bits 0-6 to ack all triggered IRQs. - */ - tmp &= ~LDINTR_STATUS_MASK & ~LDINTR_VEE; - lcdc_write(priv, _LDINTR, tmp); + /* Acknowledge interrupts and disable further VSYNC End IRQs. */ + ldintr = lcdc_read(priv, _LDINTR); + lcdc_write(priv, _LDINTR, (ldintr ^ LDINTR_STATUS_MASK) & ~LDINTR_VEE); /* figure out if this interrupt is for main or sub lcd */ is_sub = (lcdc_read(priv, _LDSR) & LDSR_MSS) ? 1 : 0; @@ -342,7 +336,7 @@ static irqreturn_t sh_mobile_lcdc_irq(int irq, void *data) if (!ch->enabled) continue; - /* Frame Start */ + /* Frame End */ if (ldintr & LDINTR_FS) { if (is_sub == lcdc_chan_is_sublcd(ch)) { ch->frame_end = 1; @@ -971,9 +965,11 @@ static int sh_mobile_wait_for_vsync(struct fb_info *info) unsigned long ldintr; int ret; - /* Enable VSync End interrupt */ + /* Enable VSync End interrupt and be careful not to acknowledge any + * pending interrupt. + */ ldintr = lcdc_read(ch->lcdc, _LDINTR); - ldintr |= LDINTR_VEE; + ldintr |= LDINTR_VEE | LDINTR_STATUS_MASK; lcdc_write(ch->lcdc, _LDINTR, ldintr); ret = wait_for_completion_interruptible_timeout(&ch->vsync_completion, |