diff options
Diffstat (limited to 'drivers/dma/imx-sdma.c')
| -rw-r--r-- | drivers/dma/imx-sdma.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 75ec0754d4ad..70c0aa931ddf 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -701,6 +701,11 @@ static int sdma_config_ownership(struct sdma_channel *sdmac, return 0; } +static int is_sdma_channel_enabled(struct sdma_engine *sdma, int channel) +{ + return !!(readl(sdma->regs + SDMA_H_STATSTOP) & BIT(channel)); +} + static void sdma_enable_channel(struct sdma_engine *sdma, int channel) { writel(BIT(channel), sdma->regs + SDMA_H_START); @@ -842,7 +847,6 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac) */ desc->chn_real_count = bd->mode.count; - bd->mode.status |= BD_DONE; bd->mode.count = desc->period_len; desc->buf_ptail = desc->buf_tail; desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd; @@ -857,9 +861,21 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac) dmaengine_desc_get_callback_invoke(&desc->vd.tx, NULL); spin_lock(&sdmac->vc.lock); + /* Assign buffer ownership to SDMA */ + bd->mode.status |= BD_DONE; + if (error) sdmac->status = old_status; } + + /* + * SDMA stops cyclic channel when DMA request triggers a channel and no SDMA + * owned buffer is available (i.e. BD_DONE was set too late). + */ + if (!is_sdma_channel_enabled(sdmac->sdma, sdmac->channel)) { + dev_warn(sdmac->sdma->dev, "restart cyclic channel %d\n", sdmac->channel); + sdma_enable_channel(sdmac->sdma, sdmac->channel); + } } static void mxc_sdma_handle_channel_normal(struct sdma_channel *data) @@ -876,9 +892,9 @@ static void mxc_sdma_handle_channel_normal(struct sdma_channel *data) for (i = 0; i < sdmac->desc->num_bd; i++) { bd = &sdmac->desc->bd[i]; - if (bd->mode.status & (BD_DONE | BD_RROR)) + if (bd->mode.status & (BD_DONE | BD_RROR)) error = -EIO; - sdmac->desc->chn_real_count += bd->mode.count; + sdmac->desc->chn_real_count += bd->mode.count; } if (error) |