From fdf475fa40f1468cf43a72b270f74dc6a4a5c905 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 25 Jan 2013 11:48:00 +0200 Subject: [PATCH] dw_dmac: remove unnecessary tx_list field in dw_dma_chan The soft LLP mode is working for active descriptor only. So, we do not need to have a copy of its pointer. Signed-off-by: Andy Shevchenko Acked-by: Viresh Kumar Signed-off-by: Vinod Koul --- drivers/dma/dw_dmac.c | 20 +++++++++++++++----- drivers/dma/dw_dmac_regs.h | 1 - 2 files changed, 15 insertions(+), 6 deletions(-) diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index ddd3ad2a96a3..721beafe8f7a 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -282,9 +282,9 @@ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first) dwc_initialize(dwc); - dwc->tx_list = &first->tx_list; dwc->tx_node_active = &first->tx_list; + /* Submit first block */ dwc_do_single_block(dwc, first); return; @@ -402,15 +402,25 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) dma_writel(dw, CLEAR.XFER, dwc->mask); if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) { - if (dwc->tx_node_active != dwc->tx_list) { - desc = to_dw_desc(dwc->tx_node_active); + struct list_head *head, *active = dwc->tx_node_active; + + /* + * We are inside first active descriptor. + * Otherwise something is really wrong. + */ + desc = dwc_first_active(dwc); + + head = &desc->tx_list; + if (active != head) { + child = to_dw_desc(active); /* Submit next block */ - dwc_do_single_block(dwc, desc); - spin_unlock_irqrestore(&dwc->lock, flags); + dwc_do_single_block(dwc, child); + spin_unlock_irqrestore(&dwc->lock, flags); return; } + /* We are done here */ clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); } diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h index fef296de4af1..13000d2b3352 100644 --- a/drivers/dma/dw_dmac_regs.h +++ b/drivers/dma/dw_dmac_regs.h @@ -194,7 +194,6 @@ struct dw_dma_chan { bool initialized; /* software emulation of the LLP transfers */ - struct list_head *tx_list; struct list_head *tx_node_active; spinlock_t lock; -- 2.20.1