diff options
| -rw-r--r-- | drivers/dma/at_hdmac.c | 54 |
1 files changed, 30 insertions, 24 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index fbfb207104e9..e2c46f32b284 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -293,7 +293,7 @@ static struct at_desc *atc_get_desc_by_cookie(struct at_dma_chan *atchan, * @current_len: the number of bytes left before reading CTRLA * @ctrla: the value of CTRLA */ -static inline int atc_calc_bytes_left(int current_len, u32 ctrla) +static inline u32 atc_calc_bytes_left(u32 current_len, u32 ctrla) { u32 btsize = (ctrla & ATC_BTSIZE_MAX); u32 src_width = ATC_REG_TO_SRC_WIDTH(ctrla); @@ -308,17 +308,20 @@ static inline int atc_calc_bytes_left(int current_len, u32 ctrla) } /** - * atc_get_bytes_left - get the number of bytes residue for a cookie + * atc_get_bytes_left - get the number of bytes residue for a cookie. + * The residue is passed by address and updated on success. * @chan: DMA channel * @cookie: transaction identifier to check status of + * @residue: residue to be updated. + * Return 0 on success, -errono otherwise. */ -static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie) +static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie, + u32 *residue) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_desc *desc_first = atc_first_active(atchan); struct at_desc *desc; - int ret; - u32 ctrla, dscr; + u32 len, ctrla, dscr; unsigned int i; /* @@ -333,7 +336,7 @@ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie) return desc->total_len; /* cookie matches to the currently running transfer */ - ret = desc_first->total_len; + len = desc_first->total_len; if (desc_first->lli.dscr) { /* hardware linked list transfer */ @@ -419,29 +422,31 @@ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie) return -ETIMEDOUT; /* for the first descriptor we can be more accurate */ - if (desc_first->lli.dscr == dscr) - return atc_calc_bytes_left(ret, ctrla); + if (desc_first->lli.dscr == dscr) { + *residue = atc_calc_bytes_left(len, ctrla); + return 0; + } - ret -= desc_first->len; + len -= desc_first->len; list_for_each_entry(desc, &desc_first->tx_list, desc_node) { if (desc->lli.dscr == dscr) break; - ret -= desc->len; + len -= desc->len; } /* * For the current descriptor in the chain we can calculate * the remaining bytes using the channel's register. */ - ret = atc_calc_bytes_left(ret, ctrla); + *residue = atc_calc_bytes_left(len, ctrla); } else { /* single transfer */ ctrla = channel_readl(atchan, CTRLA); - ret = atc_calc_bytes_left(ret, ctrla); + *residue = atc_calc_bytes_left(len, ctrla); } - return ret; + return 0; } /** @@ -1457,31 +1462,32 @@ atc_tx_status(struct dma_chan *chan, { struct at_dma_chan *atchan = to_at_dma_chan(chan); unsigned long flags; - enum dma_status ret; - int bytes = 0; + enum dma_status dma_status; + u32 residue; + int ret; - ret = dma_cookie_status(chan, cookie, txstate); - if (ret == DMA_COMPLETE || !txstate) - return ret; + dma_status = dma_cookie_status(chan, cookie, txstate); + if (dma_status == DMA_COMPLETE || !txstate) + return dma_status; spin_lock_irqsave(&atchan->lock, flags); /* Get number of bytes left in the active transactions */ - bytes = atc_get_bytes_left(chan, cookie); + ret = atc_get_bytes_left(chan, cookie, &residue); spin_unlock_irqrestore(&atchan->lock, flags); - if (unlikely(bytes < 0)) { + if (unlikely(ret < 0)) { dev_vdbg(chan2dev(chan), "get residual bytes error\n"); return DMA_ERROR; } else { - dma_set_residue(txstate, bytes); + dma_set_residue(txstate, residue); } - dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d residue = %d\n", - ret, cookie, bytes); + dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d residue = %u\n", + dma_status, cookie, residue); - return ret; + return dma_status; } /** |