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References: <20190116220154.1026171-1-vijaykhemka@fb.com>
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From:   Joel Stanley <joel@jms.id.au>
Date:   Thu, 17 Jan 2019 17:17:16 +1100
Message-ID: <CACPK8XdCVvUaCFsMXdEkc9KG0TQCGpYV55u-X7pY7vBLLHuQtw@mail.gmail.com>
Subject: Re: [PATCH v2] misc: aspeed-lpc-ctrl: make parameter optional
To:     Vijay Khemka <vijaykhemka@fb.com>, Andrew Jeffery <andrew@aj.id.au>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        linux-aspeed@lists.ozlabs.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "openbmc @ lists . ozlabs . org" <openbmc@lists.ozlabs.org>
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Sender: linux-kernel-owner@vger.kernel.org
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On Thu, 17 Jan 2019 at 09:02, Vijay Khemka <vijaykhemka@fb.com> wrote:
>
> Makiing memory-region and flash as optional parameter in device
> tree if user needs to use these parameter through ioctl then
> need to define in devicetree.
>
> Signed-off-by: Vijay Khemka <vijaykhemka@fb.com>

Thanks! This looks okay to me. I tested it on one of our systems which
uses both flash and reserved memory and it was fine.

Reviewed-by: Joel Stanley <joel@jms.id.au>

Can you also send a patch to update the bindings at
Documentation/devicetree/bindings/mfd/aspeed-lpc.txt ? I think the
only change you need to make is to move the memory region and flash
properties to optional (instead of required).

Cheers,

Joel

> ---
>  drivers/misc/aspeed-lpc-ctrl.c | 58 +++++++++++++++++++++-------------
>  1 file changed, 36 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c
> index a024f8042259..332210e06e98 100644
> --- a/drivers/misc/aspeed-lpc-ctrl.c
> +++ b/drivers/misc/aspeed-lpc-ctrl.c
> @@ -68,6 +68,7 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
>                 unsigned long param)
>  {
>         struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
> +       struct device *dev = file->private_data;
>         void __user *p = (void __user *)param;
>         struct aspeed_lpc_ctrl_mapping map;
>         u32 addr;
> @@ -90,6 +91,12 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
>                 if (map.window_id != 0)
>                         return -EINVAL;
>
> +               /* If memory-region is not described in device tree */
> +               if (!lpc_ctrl->mem_size) {
> +                       dev_err(dev, "Didn't find reserved memory\n");
> +                       return -EINVAL;
> +               }
> +
>                 map.size = lpc_ctrl->mem_size;
>
>                 return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0;
> @@ -126,9 +133,18 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
>                         return -EINVAL;
>
>                 if (map.window_type == ASPEED_LPC_CTRL_WINDOW_FLASH) {
> +                       if (!lpc_ctrl->pnor_size) {
> +                               dev_err(dev, "Didn't find host pnor flash\n");
> +                               return -EINVAL;
> +                       }
>                         addr = lpc_ctrl->pnor_base;
>                         size = lpc_ctrl->pnor_size;
>                 } else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) {
> +                       /* If memory-region is not described in device tree */
> +                       if (!lpc_ctrl->mem_size) {
> +                               dev_err(dev, "Didn't find reserved memory\n");
> +                               return -EINVAL;
> +                       }
>                         addr = lpc_ctrl->mem_base;
>                         size = lpc_ctrl->mem_size;
>                 } else {
> @@ -196,17 +212,17 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
>         if (!lpc_ctrl)
>                 return -ENOMEM;
>
> +       /* If flash is described in device tree then store */
>         node = of_parse_phandle(dev->of_node, "flash", 0);
>         if (!node) {
> -               dev_err(dev, "Didn't find host pnor flash node\n");
> -               return -ENODEV;
> -       }
> -
> -       rc = of_address_to_resource(node, 1, &resm);
> -       of_node_put(node);
> -       if (rc) {
> -               dev_err(dev, "Couldn't address to resource for flash\n");
> -               return rc;
> +               dev_dbg(dev, "Didn't find host pnor flash node\n");
> +       } else {
> +               rc = of_address_to_resource(node, 1, &resm);
> +               of_node_put(node);
> +               if (rc) {
> +                       dev_err(dev, "Couldn't address to resource for flash\n");
> +                       return rc;
> +               }
>         }
>
>         lpc_ctrl->pnor_size = resource_size(&resm);
> @@ -214,22 +230,22 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
>
>         dev_set_drvdata(&pdev->dev, lpc_ctrl);
>
> +       /* If memory-region is described in device tree then store */
>         node = of_parse_phandle(dev->of_node, "memory-region", 0);
>         if (!node) {
> -               dev_err(dev, "Didn't find reserved memory\n");
> -               return -EINVAL;
> -       }
> +               dev_dbg(dev, "Didn't find reserved memory\n");
> +       } else {
> +               rc = of_address_to_resource(node, 0, &resm);
> +               of_node_put(node);
> +               if (rc) {
> +                       dev_err(dev, "Couldn't address to resource for reserved memory\n");
> +                       return -ENOMEM;
> +               }
>
> -       rc = of_address_to_resource(node, 0, &resm);
> -       of_node_put(node);
> -       if (rc) {
> -               dev_err(dev, "Couldn't address to resource for reserved memory\n");
> -               return -ENOMEM;
> +               lpc_ctrl->mem_size = resource_size(&resm);
> +               lpc_ctrl->mem_base = resm.start;
>         }
>
> -       lpc_ctrl->mem_size = resource_size(&resm);
> -       lpc_ctrl->mem_base = resm.start;
> -
>         lpc_ctrl->regmap = syscon_node_to_regmap(
>                         pdev->dev.parent->of_node);
>         if (IS_ERR(lpc_ctrl->regmap)) {
> @@ -258,8 +274,6 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
>                 goto err;
>         }
>
> -       dev_info(dev, "Loaded at %pr\n", &resm);
> -
>         return 0;
>
>  err:
> --
> 2.17.1
>