Re: [PATCH v3 2/5] dmaengine: Add STM32 DMAMUX driver
From: Vinod Koul
Date: Wed Jul 26 2017 - 01:26:55 EST
On Mon, Jul 24, 2017 at 01:55:10PM +0000, Pierre Yves MORDRET wrote:
> >> +
> >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >> + if (!res)
> >> + return -ENODEV;
> >> +
> >> + iomem = devm_ioremap_resource(&pdev->dev, res);
> >> + if (!iomem)
> >> + return -ENOMEM;
> >> +
> >> + spin_lock_init(&stm32_dmamux->lock);
> >> +
> >> + stm32_dmamux->clk = devm_clk_get(&pdev->dev, NULL);
> >> + if (IS_ERR(stm32_dmamux->clk)) {
> >> + dev_info(&pdev->dev, "Missing controller clock\n");
> >
> > Can you check for EPROBE_DEFER and print only for if that is not the error
> > otherwise we end up sapmming with defered probe issues
> >
>
> This is what you meant ?
> if (IS_ERR(stm32_dmamux->clk) != EPROBE_DEFER) {
> dev_info(&pdev->dev, "Missing controller clock\n");
> return PTR_ERR(stm32_dmamux->clk);
> }
>
> OR
>
> if (IS_ERR(stm32_dmamux->clk)) {
> if (IS_ERR(stm32_dmamux->clk) != EPROBE_DEFER)
> dev_info(&pdev->dev, "Missing controller clock\n");
> return PTR_ERR(stm32_dmamux->clk);
> }
This one please
>
> >> +
> >> +#ifndef __DMA_STM32_DMAMUX_H
> >> +#define __DMA_STM32_DMAMUX_H
> >> +
> >> +#if defined(CONFIG_STM32_DMAMUX)
> >> +int stm32_dmamux_set_config(struct device *dev, void *route_data, u32 chan_id);
> >
> > Why do we need a custom API in this case?
> >
>
> This API is called by DMA when a slave is requested by client. DMA can work
> without DMAMUX this API has been put in place to configure DMAMUX whether client
> is requesting a DMAMUX Channel instead of a DMA one.
You mean the dmaengine driver right?
--
~Vinod