The recently submitted fix-commit revealed a problem in the iDMA 32-bit platform code. Even though the controller supported only a single master the dw_dma_acpi_filter() method hard-coded two master interfaces with IDs 0 and 1. As a result the sanity check implemented in the commit b336268dde75 ("dmaengine: dw: Add peripheral bus width verification") got incorrect interface data width and thus prevented the client drivers from configuring the DMA-channel with the EINVAL error returned. E.g., the next error was printed for the PXA2xx SPI controller driver trying to configure the requested channels:

[ 164.525604] pxa2xx_spi_pci 0000:00:07.1: DMA slave config failed [ 164.536105] pxa2xx_spi_pci 0000:00:07.1: failed to get DMA TX descriptor [ 164.543213] spidev spi-SPT0001:00: SPI transfer failed: -16

The problem would have been spotted much earlier if the iDMA 32-bit controller supported more than one master interfaces. But since it supports just a single master and the iDMA 32-bit specific code just ignores the master IDs in the CTLLO preparation method, the issue has been gone unnoticed so far.

Fix the problem by specifying the default master ID for both memory and peripheral devices in the driver data. Thus the issue noticed for the iDMA 32-bit controllers will be eliminated and the ACPI-probed DW DMA controllers will be configured with the correct master ID by default.

Cc: stable@vger.kernel.org Fixes: b336268dde75 ("dmaengine: dw: Add peripheral bus width verification") Fixes: 199244d69458 ("dmaengine: dw: add support of iDMA 32-bit hardware") Reported-by: Ferry Toth fntoth@gmail.com Closes: https://lore.kernel.org/dmaengine/ZuXbCKUs1iOqFu51@black.fi.intel.com/ Reported-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Closes: https://lore.kernel.org/dmaengine/ZuXgI-VcHpMgbZ91@black.fi.intel.com/ Tested-by: Ferry Toth fntoth@gmail.com Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com --- v5: rebranded to follow the compliances

Vinod, please apply this for v6.12-rcX as we have a problem to fix.

drivers/dma/dw/acpi.c | 6 ++++-- drivers/dma/dw/internal.h | 8 ++++++++ drivers/dma/dw/pci.c | 4 ++-- 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/dw/acpi.c b/drivers/dma/dw/acpi.c index c510c109d2c3..b6452fffa657 100644 --- a/drivers/dma/dw/acpi.c +++ b/drivers/dma/dw/acpi.c @@ -8,13 +8,15 @@

static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param) { + struct dw_dma *dw = to_dw_dma(chan->device); + struct dw_dma_chip_pdata *data = dev_get_drvdata(dw->dma.dev); struct acpi_dma_spec *dma_spec = param; struct dw_dma_slave slave = { .dma_dev = dma_spec->dev, .src_id = dma_spec->slave_id, .dst_id = dma_spec->slave_id, - .m_master = 0, - .p_master = 1, + .m_master = data->m_master, + .p_master = data->p_master, };

return dw_dma_filter(chan, &slave); diff --git a/drivers/dma/dw/internal.h b/drivers/dma/dw/internal.h index 563ce73488db..f1bd06a20cd6 100644 --- a/drivers/dma/dw/internal.h +++ b/drivers/dma/dw/internal.h @@ -51,11 +51,15 @@ struct dw_dma_chip_pdata { int (*probe)(struct dw_dma_chip *chip); int (*remove)(struct dw_dma_chip *chip); struct dw_dma_chip *chip; + u8 m_master; + u8 p_master; };

static __maybe_unused const struct dw_dma_chip_pdata dw_dma_chip_pdata = { .probe = dw_dma_probe, .remove = dw_dma_remove, + .m_master = 0, + .p_master = 1, };

static const struct dw_dma_platform_data idma32_pdata = { @@ -72,6 +76,8 @@ static __maybe_unused const struct dw_dma_chip_pdata idma32_chip_pdata = { .pdata = &idma32_pdata, .probe = idma32_dma_probe, .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, };

static const struct dw_dma_platform_data xbar_pdata = { @@ -88,6 +94,8 @@ static __maybe_unused const struct dw_dma_chip_pdata xbar_chip_pdata = { .pdata = &xbar_pdata, .probe = idma32_dma_probe, .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, };

#endif /* _DMA_DW_INTERNAL_H */ diff --git a/drivers/dma/dw/pci.c b/drivers/dma/dw/pci.c index ad2d4d012cf7..e8a0eb81726a 100644 --- a/drivers/dma/dw/pci.c +++ b/drivers/dma/dw/pci.c @@ -56,10 +56,10 @@ static int dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *pid) if (ret) return ret;

- dw_dma_acpi_controller_register(chip->dw); - pci_set_drvdata(pdev, data);

+ dw_dma_acpi_controller_register(chip->dw); + return 0; }