@@ -1573,7 +1573,6 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
INIT_LIST_HEAD(&dw->dma.channels);
for (i = 0; i < nr_channels; i++) {
struct dw_dma_chan *dwc = &dw->chan[i];
- int r = nr_channels - i - 1;
dwc->chan.device = &dw->dma;
dma_cookie_init(&dwc->chan);
@@ -1585,7 +1584,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
/* 7 is highest priority & 0 is lowest. */
if (pdata->chan_priority == CHAN_PRIORITY_ASCENDING)
- dwc->priority = r;
+ dwc->priority = nr_channels - i - 1;
else
dwc->priority = i;
@@ -1605,6 +1604,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
/* Hardware configuration */
if (autocfg) {
unsigned int dwc_params;
+ unsigned int r = DW_DMA_MAX_NR_CHANNELS - i - 1;
void __iomem *addr = chip->regs + r * sizeof(u32);
dwc_params = dma_read_byaddr(addr, DWC_PARAMS);
This is a note to let you know that I have just added a patch titled dmaengine: dw: properly read DWC_PARAMS register to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt19. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 1bb698181e790b2a8e46b25b890481077a0de244 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Date: Mon, 28 Sep 2015 18:57:03 +0300 Subject: dmaengine: dw: properly read DWC_PARAMS register commit 6bea0f6d1c47b07be88dfd93f013ae05fcb3d8bf upstream. In case we have less than maximum allowed channels (8) and autoconfiguration is enabled the DWC_PARAMS read is wrong because it uses different arithmetic to what is needed for channel priority setup. Re-do the caclulations properly. This now works on AVR32 board well. Fixes: fed2574b3c9f (dw_dmac: introduce software emulation of LLP transfers) Cc: yitian.bu@tangramtek.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/dma/dw/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)