When doing the slave configuration, an error is returned if the maxburst value is not supported. The bug comes from the fact that we always check the maxburst for both directions but in the case of an unidirectional channel, only one is set.
Signed-off-by: Ludovic Desroches <[email protected]> Cc: <[email protected]> # 3.19 and later --- drivers/dma/at_xdmac.c | 97 +++++++++++++++++++++++++++----------------------- 1 file changed, 52 insertions(+), 45 deletions(-) diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index d9891d3..30e161b 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -501,54 +501,61 @@ static int at_xdmac_set_slave_config(struct dma_chan *chan, u8 dwidth; int csize; - atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] = - AT91_XDMAC_DT_PERID(atchan->perid) - | AT_XDMAC_CC_DAM_INCREMENTED_AM - | AT_XDMAC_CC_SAM_FIXED_AM - | AT_XDMAC_CC_DIF(atchan->memif) - | AT_XDMAC_CC_SIF(atchan->perif) - | AT_XDMAC_CC_SWREQ_HWR_CONNECTED - | AT_XDMAC_CC_DSYNC_PER2MEM - | AT_XDMAC_CC_MBSIZE_SIXTEEN - | AT_XDMAC_CC_TYPE_PER_TRAN; - csize = at_xdmac_csize(sconfig->src_maxburst); - if (csize < 0) { - dev_err(chan2dev(chan), "invalid src maxburst value\n"); - return -EINVAL; - } - atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_CSIZE(csize); - dwidth = ffs(sconfig->src_addr_width) - 1; - atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); - - - atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] = - AT91_XDMAC_DT_PERID(atchan->perid) - | AT_XDMAC_CC_DAM_FIXED_AM - | AT_XDMAC_CC_SAM_INCREMENTED_AM - | AT_XDMAC_CC_DIF(atchan->perif) - | AT_XDMAC_CC_SIF(atchan->memif) - | AT_XDMAC_CC_SWREQ_HWR_CONNECTED - | AT_XDMAC_CC_DSYNC_MEM2PER - | AT_XDMAC_CC_MBSIZE_SIXTEEN - | AT_XDMAC_CC_TYPE_PER_TRAN; - csize = at_xdmac_csize(sconfig->dst_maxburst); - if (csize < 0) { - dev_err(chan2dev(chan), "invalid src maxburst value\n"); - return -EINVAL; + if (sconfig->src_addr) { + atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] = + AT91_XDMAC_DT_PERID(atchan->perid) + | AT_XDMAC_CC_DAM_INCREMENTED_AM + | AT_XDMAC_CC_SAM_FIXED_AM + | AT_XDMAC_CC_DIF(atchan->memif) + | AT_XDMAC_CC_SIF(atchan->perif) + | AT_XDMAC_CC_SWREQ_HWR_CONNECTED + | AT_XDMAC_CC_DSYNC_PER2MEM + | AT_XDMAC_CC_MBSIZE_SIXTEEN + | AT_XDMAC_CC_TYPE_PER_TRAN; + csize = at_xdmac_csize(sconfig->src_maxburst); + if (csize < 0) { + dev_err(chan2dev(chan), "invalid src maxburst value\n"); + return -EINVAL; + } + atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_CSIZE(csize); + dwidth = ffs(sconfig->src_addr_width) - 1; + atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); + /* Src addr is needed to configure the link list descriptor. */ + atchan->per_src_addr = sconfig->src_addr; + + dev_dbg(chan2dev(chan), + "%s: cfg[dev2mem]=0x%08x, per_src_addr=0x%08x\n", + __func__, atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG], + atchan->per_src_addr); } - atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_CSIZE(csize); - dwidth = ffs(sconfig->dst_addr_width) - 1; - atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); - /* Src and dst addr are needed to configure the link list descriptor. */ - atchan->per_src_addr = sconfig->src_addr; - atchan->per_dst_addr = sconfig->dst_addr; + if (sconfig->dst_addr) { + atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] = + AT91_XDMAC_DT_PERID(atchan->perid) + | AT_XDMAC_CC_DAM_FIXED_AM + | AT_XDMAC_CC_SAM_INCREMENTED_AM + | AT_XDMAC_CC_DIF(atchan->perif) + | AT_XDMAC_CC_SIF(atchan->memif) + | AT_XDMAC_CC_SWREQ_HWR_CONNECTED + | AT_XDMAC_CC_DSYNC_MEM2PER + | AT_XDMAC_CC_MBSIZE_SIXTEEN + | AT_XDMAC_CC_TYPE_PER_TRAN; + csize = at_xdmac_csize(sconfig->dst_maxburst); + if (csize < 0) { + dev_err(chan2dev(chan), "invalid src maxburst value\n"); + return -EINVAL; + } + atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_CSIZE(csize); + dwidth = ffs(sconfig->dst_addr_width) - 1; + atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); + /* Dst addr is needed to configure the link list descriptor. */ + atchan->per_dst_addr = sconfig->dst_addr; - dev_dbg(chan2dev(chan), - "%s: cfg[dev2mem]=0x%08x, cfg[mem2dev]=0x%08x, per_src_addr=0x%08x, per_dst_addr=0x%08x\n", - __func__, atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG], - atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG], - atchan->per_src_addr, atchan->per_dst_addr); + dev_dbg(chan2dev(chan), + "%s: cfg[mem2dev]=0x%08x, per_dst_addr=0x%08x\n", + __func__, atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG], + atchan->per_dst_addr); + } return 0; } -- 2.2.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
