Re: [PATCH v2 2/2] mtd: rawnand: Add NAND controller support on Intel LGM SoC

From: Andy Shevchenko
Date: Sun Apr 19 2020 - 18:28:22 EST


On Fri, Apr 17, 2020 at 04:21:47PM +0800, Ramuthevar,Vadivel MuruganX wrote:
> From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
>
> This patch adds the new IP of Nand Flash Controller(NFC) support
> on Intel's Lightning Mountain(LGM) SoC.
>
> DMA is used for burst data transfer operation, also DMA HW supports
> aligned 32bit memory address and aligned data access by default.
> DMA burst of 8 supported. Data register used to support the read/write
> operation from/to device.
>
> NAND controller driver implements ->exec_op() to replace legacy hooks,
> these specific call-back method to execute NAND operations.

I guess untested version slipped into mailing list...
See below why.

...

> +#include <linux/clk.h>
> +#include <linux/completion.h>
> +#include <linux/dmaengine.h>
> +#include <linux/dma-direction.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/resource.h>
> +#include <linux/sched.h>
> +#include <linux/types.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/rawnand.h>
> +#include <linux/mtd/nand_ecc.h>
> +#include <linux/platform_device.h>

> +#include <linux/of.h>

Do you need this?

> +#include <linux/mtd/partitions.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <mtd/mtd-abi.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/mtd/nand.h>

Basically, do you need all of them?

And maybe keep them in order?

...

> +static int lgm_dma_init(struct device *dev, struct lgm_nand_host *lgm_host)
> +{
> + int ret;
> +
> + /* Prepare for TX DMA: */
> + lgm_host->dma_tx = dma_request_chan(dev, "tx");
> + if (IS_ERR(lgm_host->dma_tx)) {
> + ret = PTR_ERR(lgm_host->dma_tx);
> + dev_err(dev, "can't get the TX DMA channel, error %d!\n", ret);
> + goto err;
> + }
> +
> + /* Prepare for RX: */
> + lgm_host->dma_rx = dma_request_chan(dev, "rx");
> + if (IS_ERR(lgm_host->dma_rx)) {
> + ret = PTR_ERR(lgm_host->dma_rx);
> + dev_err(dev, "can't get the RX DMA channel, error %d\n", ret);

I suspect this error path hasn't been tested. I don't see where tx channel
freeing is happening.

> + goto err;
> + }
> +
> + return 0;

> +err:
> + return ret;

Redundant label.

> +}

...

> + res = devm_platform_ioremap_resource_byname(pdev, lgm_host->cs_name);
> + lgm_host->nandaddr_va = res;
> + nandaddr_pa = res->start;
> + if (IS_ERR(lgm_host->nandaddr_va))
> + return PTR_ERR(lgm_host->nandaddr_va);

I'm wondering what is this. How is it even compile?

--
With Best Regards,
Andy Shevchenko