2020-02-27 12:38:46

by Peter Ujfalusi

[permalink] [raw]
Subject: [PATCH 4/7] mtd: rawnand: sunxi: Use dma_request_chan() instead dma_request_slave_channel()

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <[email protected]>
---
drivers/mtd/nand/raw/sunxi_nand.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
index 37a4ac0dd85b..3a24c4512af7 100644
--- a/drivers/mtd/nand/raw/sunxi_nand.c
+++ b/drivers/mtd/nand/raw/sunxi_nand.c
@@ -2123,8 +2123,16 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
if (ret)
goto out_ahb_reset_reassert;

- nfc->dmac = dma_request_slave_channel(dev, "rxtx");
- if (nfc->dmac) {
+ nfc->dmac = dma_request_chan(dev, "rxtx");
+ if (IS_ERR(nfc->dmac)) {
+ ret = PTR_ERR(nfc->dmac);
+ if (ret == -EPROBE_DEFER)
+ goto out_ahb_reset_reassert;
+
+ /* Ignore errors to fall back to PIO mode */
+ dev_warn(dev, "failed to request rxtx DMA channel: %d\n", ret);
+ nfc->dmac = NULL;
+ } else {
struct dma_slave_config dmac_cfg = { };

dmac_cfg.src_addr = r->start + nfc->caps->reg_io_data;
@@ -2138,9 +2146,6 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
if (nfc->caps->extra_mbus_conf)
writel(readl(nfc->regs + NFC_REG_CTL) |
NFC_DMA_TYPE_NORMAL, nfc->regs + NFC_REG_CTL);
-
- } else {
- dev_warn(dev, "failed to request rxtx DMA channel\n");
}

platform_set_drvdata(pdev, nfc);
--
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki


2020-03-09 09:59:10

by Maxime Ripard

[permalink] [raw]
Subject: Re: [PATCH 4/7] mtd: rawnand: sunxi: Use dma_request_chan() instead dma_request_slave_channel()

On Thu, Feb 27, 2020 at 02:37:46PM +0200, Peter Ujfalusi wrote:
> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
>
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
>
> Signed-off-by: Peter Ujfalusi <[email protected]>

Acked-by: Maxime Ripard <[email protected]>

Thanks!
Maxime

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2020-03-10 18:31:58

by Miquel Raynal

[permalink] [raw]
Subject: Re: [PATCH 4/7] mtd: rawnand: sunxi: Use dma_request_chan() instead dma_request_slave_channel()

On Thu, 2020-02-27 at 12:37:46 UTC, Peter Ujfalusi wrote:
> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
>
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
>
> Signed-off-by: Peter Ujfalusi <[email protected]>
> Acked-by: Maxime Ripard <[email protected]>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next, thanks.

Miquel