diff mbox series

[v2] misc: aspeed-lpc-ctrl: make parameter optional

Message ID 20190116220154.1026171-1-vijaykhemka@fb.com
State Accepted, archived
Headers show
Series [v2] misc: aspeed-lpc-ctrl: make parameter optional | expand

Commit Message

Vijay Khemka Jan. 16, 2019, 10:01 p.m. UTC 
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>
---
 drivers/misc/aspeed-lpc-ctrl.c | 58 +++++++++++++++++++++-------------
 1 file changed, 36 insertions(+), 22 deletions(-)

Comments

Joel Stanley Jan. 17, 2019, 6:17 a.m. UTC | #1 
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
>
Vijay Khemka Jan. 17, 2019, 6:53 p.m. UTC | #2 
On 1/16/19, 10:17 PM, "Joel Stanley" <joel@jms.id.au> wrote:

    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).

Sure I will do this.
    
    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
    >
Andrew Jeffery Jan. 18, 2019, 4:58 a.m. UTC | #3 
Hi Vijay,

Thanks for doing the work to fix the driver. Some minor queries/points
below.

On Thu, 17 Jan 2019, at 08:31, Vijay Khemka 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>
> ---
>  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;

I feel like EINVAL isn't quite right - it's pretty generic, and the parameter
value changes its validity with the devicetree context. My gut instinct
would be to use EINVAL for parameter values that violate assumptions
of the driver rather than violate configuration of the driver. Maybe ENXIO
("No such device or address") is an improvement: "I can't map that device
because there's no such device or address"?

> +		}
> +
>  		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;

See the error code discussion above. Also, this is userspace's error not 
the kernel's, so I think dev_err() is a bit harsh. Probably best to just let
userspace log the error if it thinks the it is concerning.

> +			}
>  			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;

as above.

> +			}
>  			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;

Wow, I think this is an abuse of ENOMEM. Its description is "Out of memory"
which doesn't really reflect the problem here.

Not really your fault though, maybe we'll fix that with some follow-up patches.

Cheers,

Andrew

> +		}
>  
> -	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
>
Vijay Khemka Jan. 18, 2019, 8:12 p.m. UTC | #4 
Hi Andrew,
Thanks for this review, I will have a follow up patch for this return values.

Regards
-Vijay

On 1/17/19, 8:58 PM, "Andrew Jeffery" <andrew@aj.id.au> wrote:

    Hi Vijay,
    
    Thanks for doing the work to fix the driver. Some minor queries/points
    below.
    
    On Thu, 17 Jan 2019, at 08:31, Vijay Khemka 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>
    > ---
    >  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;
    
    I feel like EINVAL isn't quite right - it's pretty generic, and the parameter
    value changes its validity with the devicetree context. My gut instinct
    would be to use EINVAL for parameter values that violate assumptions
    of the driver rather than violate configuration of the driver. Maybe ENXIO
    ("No such device or address") is an improvement: "I can't map that device
    because there's no such device or address"?
    
    > +		}
    > +
    >  		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;
    
    See the error code discussion above. Also, this is userspace's error not 
    the kernel's, so I think dev_err() is a bit harsh. Probably best to just let
    userspace log the error if it thinks the it is concerning.
    
    > +			}
    >  			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;
    
    as above.
    
    > +			}
    >  			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;
    
    Wow, I think this is an abuse of ENOMEM. Its description is "Out of memory"
    which doesn't really reflect the problem here.
    
    Not really your fault though, maybe we'll fix that with some follow-up patches.
    
    Cheers,
    
    Andrew
    
    > +		}
    >  
    > -	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
    >
Joel Stanley May 1, 2019, 5:55 a.m. UTC | #5 
On Fri, 18 Jan 2019 at 20:12, Vijay Khemka <vijaykhemka@fb.com> wrote:
>
> Hi Andrew,
> Thanks for this review, I will have a follow up patch for this return values.

Did you send a follow up patch to fix the return values?

Greg, is there any reason why you did not merge this one? 5.2 will
have device trees that depend on this patch's behavior.

Cheers,

Joel

> On 1/17/19, 8:58 PM, "Andrew Jeffery" <andrew@aj.id.au> wrote:
>
>     Hi Vijay,
>
>     Thanks for doing the work to fix the driver. Some minor queries/points
>     below.
>
>     On Thu, 17 Jan 2019, at 08:31, Vijay Khemka 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>
>     > ---
>     >  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;
>
>     I feel like EINVAL isn't quite right - it's pretty generic, and the parameter
>     value changes its validity with the devicetree context. My gut instinct
>     would be to use EINVAL for parameter values that violate assumptions
>     of the driver rather than violate configuration of the driver. Maybe ENXIO
>     ("No such device or address") is an improvement: "I can't map that device
>     because there's no such device or address"?
>
>     > +         }
>     > +
>     >           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;
>
>     See the error code discussion above. Also, this is userspace's error not
>     the kernel's, so I think dev_err() is a bit harsh. Probably best to just let
>     userspace log the error if it thinks the it is concerning.
>
>     > +                 }
>     >                   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;
>
>     as above.
>
>     > +                 }
>     >                   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;
>
>     Wow, I think this is an abuse of ENOMEM. Its description is "Out of memory"
>     which doesn't really reflect the problem here.
>
>     Not really your fault though, maybe we'll fix that with some follow-up patches.
>
>     Cheers,
>
>     Andrew
>
>     > +         }
>     >
>     > - 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
>     >
>
>
Greg Kroah-Hartman May 1, 2019, 6:45 a.m. UTC | #6 
On Wed, May 01, 2019 at 05:55:07AM +0000, Joel Stanley wrote:
> On Fri, 18 Jan 2019 at 20:12, Vijay Khemka <vijaykhemka@fb.com> wrote:
> >
> > Hi Andrew,
> > Thanks for this review, I will have a follow up patch for this return values.
> 
> Did you send a follow up patch to fix the return values?
> 
> Greg, is there any reason why you did not merge this one? 5.2 will
> have device trees that depend on this patch's behavior.

No idea, if it needs to be applied, please resend.

thanks,

greg k-h
Vijay Khemka May 1, 2019, 10:22 p.m. UTC | #7 
Let me send both patches.

On 4/30/19, 11:45 PM, "Greg Kroah-Hartman" <gregkh@linuxfoundation.org> wrote:

    On Wed, May 01, 2019 at 05:55:07AM +0000, Joel Stanley wrote:
    > On Fri, 18 Jan 2019 at 20:12, Vijay Khemka <vijaykhemka@fb.com> wrote:
    > >
    > > Hi Andrew,
    > > Thanks for this review, I will have a follow up patch for this return values.
    > 
    > Did you send a follow up patch to fix the return values?
    > 
    > Greg, is there any reason why you did not merge this one? 5.2 will
    > have device trees that depend on this patch's behavior.
    
    No idea, if it needs to be applied, please resend.
    
    thanks,
    
    greg k-h
diff mbox series

Patch

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: