From 6d5f37f166bb07b04b4d42e9d1f5427b7931cd3c Mon Sep 17 00:00:00 2001 From: Abhishek Sahu Date: Mon, 12 Mar 2018 18:44:53 +0530 Subject: [PATCH 04/13] i2c: qup: remove redundant variables for BAM SG count The rx_nents and tx_nents are redundant. rx_buf and tx_buf can be used for total number of SG entries. Since rx_buf and tx_buf give the impression that it is buffer instead of count so rename it to tx_cnt and rx_cnt for giving it more meaningful variable name. Signed-off-by: Abhishek Sahu Reviewed-by: Austin Christ Reviewed-by: Andy Gross Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-qup.c | 42 ++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 24 deletions(-) --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -683,8 +683,8 @@ static int qup_i2c_bam_do_xfer(struct qu struct dma_async_tx_descriptor *txd, *rxd = NULL; int ret = 0, idx = 0, limit = QUP_READ_LIMIT; dma_cookie_t cookie_rx, cookie_tx; - u32 rx_nents = 0, tx_nents = 0, len, blocks, rem; - u32 i, tlen, tx_len, tx_buf = 0, rx_buf = 0, off = 0; + u32 len, blocks, rem; + u32 i, tlen, tx_len, tx_cnt = 0, rx_cnt = 0, off = 0; u8 *tags; while (idx < num) { @@ -698,9 +698,6 @@ static int qup_i2c_bam_do_xfer(struct qu rem = msg->len - (blocks - 1) * limit; if (msg->flags & I2C_M_RD) { - rx_nents += (blocks * 2) + 1; - tx_nents += 1; - while (qup->blk.pos < blocks) { tlen = (i == (blocks - 1)) ? rem : limit; tags = &qup->start_tag.start[off + len]; @@ -708,14 +705,14 @@ static int qup_i2c_bam_do_xfer(struct qu qup->blk.data_len -= tlen; /* scratch buf to read the start and len tags */ - ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], + ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++], &qup->brx.tag.start[0], 2, qup, DMA_FROM_DEVICE); if (ret) return ret; - ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], + ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++], &msg->buf[limit * i], tlen, qup, DMA_FROM_DEVICE); @@ -725,7 +722,7 @@ static int qup_i2c_bam_do_xfer(struct qu i++; qup->blk.pos = i; } - ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], + ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->start_tag.start[off], len, qup, DMA_TO_DEVICE); if (ret) @@ -733,28 +730,26 @@ static int qup_i2c_bam_do_xfer(struct qu off += len; /* scratch buf to read the BAM EOT and FLUSH tags */ - ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], + ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++], &qup->brx.tag.start[0], 2, qup, DMA_FROM_DEVICE); if (ret) return ret; } else { - tx_nents += (blocks * 2); - while (qup->blk.pos < blocks) { tlen = (i == (blocks - 1)) ? rem : limit; tags = &qup->start_tag.start[off + tx_len]; len = qup_i2c_set_tags(tags, qup, msg, 1); qup->blk.data_len -= tlen; - ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], + ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], tags, len, qup, DMA_TO_DEVICE); if (ret) return ret; tx_len += len; - ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], + ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &msg->buf[limit * i], tlen, qup, DMA_TO_DEVICE); if (ret) @@ -766,26 +761,25 @@ static int qup_i2c_bam_do_xfer(struct qu if (idx == (num - 1)) { len = 1; - if (rx_nents) { + if (rx_cnt) { qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT; len++; } qup->btx.tag.start[len - 1] = QUP_BAM_FLUSH_STOP; - ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], + ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->btx.tag.start[0], len, qup, DMA_TO_DEVICE); if (ret) return ret; - tx_nents += 1; } } idx++; msg++; } - txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_nents, + txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_PREP_FENCE); if (!txd) { @@ -794,7 +788,7 @@ static int qup_i2c_bam_do_xfer(struct qu goto desc_err; } - if (!rx_nents) { + if (!rx_cnt) { txd->callback = qup_i2c_bam_cb; txd->callback_param = qup; } @@ -807,9 +801,9 @@ static int qup_i2c_bam_do_xfer(struct qu dma_async_issue_pending(qup->btx.dma); - if (rx_nents) { + if (rx_cnt) { rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg, - rx_nents, DMA_DEV_TO_MEM, + rx_cnt, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT); if (!rxd) { dev_err(qup->dev, "failed to get rx desc\n"); @@ -844,7 +838,7 @@ static int qup_i2c_bam_do_xfer(struct qu goto desc_err; } - if (rx_nents) + if (rx_cnt) writel(QUP_BAM_INPUT_EOT, qup->base + QUP_OUT_FIFO_BASE); @@ -862,10 +856,10 @@ static int qup_i2c_bam_do_xfer(struct qu } desc_err: - dma_unmap_sg(qup->dev, qup->btx.sg, tx_nents, DMA_TO_DEVICE); + dma_unmap_sg(qup->dev, qup->btx.sg, tx_cnt, DMA_TO_DEVICE); - if (rx_nents) - dma_unmap_sg(qup->dev, qup->brx.sg, rx_nents, + if (rx_cnt) + dma_unmap_sg(qup->dev, qup->brx.sg, rx_cnt, DMA_FROM_DEVICE); return ret;