From mboxrd@z Thu Jan 1 00:00:00 1970 From: ludovic.desroches@atmel.com (Ludovic Desroches) Date: Thu, 16 Apr 2015 17:04:00 +0200 Subject: [PATCH] dmaengine: at_xdmac: fix slave configuration issue Message-ID: <1429196640-8703-1-git-send-email-ludovic.desroches@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Cc: # 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