Re: [PATCH 3/5] nvmem: mtk-efuse: fix different address space warnings of sparse

[Sean Wang]

On Mon, 2017-09-11 at 22:01 +0900, Masahiro Yamada wrote:
> Fix the following sparse warnings:
> 
> drivers/nvmem/mtk-efuse.c:24:30: warning: incorrect type in initializer 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:24:30:expected void [noderef] *base
> drivers/nvmem/mtk-efuse.c:24:30:got void *context
> drivers/nvmem/mtk-efuse.c:37:30: warning: incorrect type in initializer 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:37:30:expected void [noderef] *base
> drivers/nvmem/mtk-efuse.c:37:30:got void *context
> drivers/nvmem/mtk-efuse.c:69:23: warning: incorrect type in assignment 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:69:23:expected void *priv
> drivers/nvmem/mtk-efuse.c:69:23:got void [noderef] *[assigned] base
> 
> The type of nvmem_config->priv is (void *), so sparse complains
> about assignment of the base address with (void __iomem *) type.
> 
> Even if we cast it out, sparse still warns:
> warning: cast removes address space of expression
> 
> Of course, we can shut up the sparse by marking __force, but a more
> correct way is to put the base address into driver private data.
> 
> Signed-off-by: Masahiro Yamada 

Acked-by: Sean Wang 

> ---
> 
>  drivers/nvmem/mtk-efuse.c | 26 +-
>  1 file changed, 17 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
> index fa7a0f6..c4058b5 100644
> --- a/drivers/nvmem/mtk-efuse.c
> +++ b/drivers/nvmem/mtk-efuse.c
> @@ -18,15 +18,19 @@
>  #include 
>  #include 
>  
> +struct mtk_efuse_priv {
> + void __iomem *base;
> +};
> +
>  static int mtk_reg_read(void *context,
>   unsigned int reg, void *_val, size_t bytes)
>  {
> - void __iomem *base = context;
> + struct mtk_efuse_priv *priv = context;
>   u32 *val = _val;
>   int i = 0, words = bytes / 4;
>  
>   while (words--)
> - *val++ = readl(base + reg + (i++ * 4));
> + *val++ = readl(priv->base + reg + (i++ * 4));
>  
>   return 0;
>  }
> @@ -34,12 +38,12 @@ static int mtk_reg_read(void *context,
>  static int mtk_reg_write(void *context,
>unsigned int reg, void *_val, size_t bytes)
>  {
> - void __iomem *base = context;
> + struct mtk_efuse_priv *priv = context;
>   u32 *val = _val;
>   int i = 0, words = bytes / 4;
>  
>   while (words--)
> - writel(*val++, base + reg + (i++ * 4));
> + writel(*val++, priv->base + reg + (i++ * 4));
>  
>   return 0;
>  }
> @@ -50,19 +54,23 @@ static int mtk_efuse_probe(struct platform_device *pdev)
>   struct resource *res;
>   struct nvmem_device *nvmem;
>   struct nvmem_config econfig = {};
> - void __iomem *base;
> + struct mtk_efuse_priv *priv;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
>  
>   res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - base = devm_ioremap_resource(dev, res);
> - if (IS_ERR(base))
> - return PTR_ERR(base);
> + priv->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(priv->base))
> + return PTR_ERR(priv->base);
>  
>   econfig.stride = 4;
>   econfig.word_size = 4;
>   econfig.reg_read = mtk_reg_read;
>   econfig.reg_write = mtk_reg_write;
>   econfig.size = resource_size(res);
> - econfig.priv = base;
> + econfig.priv = priv;
>   econfig.dev = dev;
>   econfig.owner = THIS_MODULE;
>   nvmem = nvmem_register();

Re: [PATCH 3/5] nvmem: mtk-efuse: fix different address space warnings of sparse

[Sean Wang]

On Mon, 2017-09-11 at 22:01 +0900, Masahiro Yamada wrote:
> Fix the following sparse warnings:
> 
> drivers/nvmem/mtk-efuse.c:24:30: warning: incorrect type in initializer 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:24:30:expected void [noderef] *base
> drivers/nvmem/mtk-efuse.c:24:30:got void *context
> drivers/nvmem/mtk-efuse.c:37:30: warning: incorrect type in initializer 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:37:30:expected void [noderef] *base
> drivers/nvmem/mtk-efuse.c:37:30:got void *context
> drivers/nvmem/mtk-efuse.c:69:23: warning: incorrect type in assignment 
> (different address spaces)
> drivers/nvmem/mtk-efuse.c:69:23:expected void *priv
> drivers/nvmem/mtk-efuse.c:69:23:got void [noderef] *[assigned] base
> 
> The type of nvmem_config->priv is (void *), so sparse complains
> about assignment of the base address with (void __iomem *) type.
> 
> Even if we cast it out, sparse still warns:
> warning: cast removes address space of expression
> 
> Of course, we can shut up the sparse by marking __force, but a more
> correct way is to put the base address into driver private data.
> 
> Signed-off-by: Masahiro Yamada 

Acked-by: Sean Wang 

> ---
> 
>  drivers/nvmem/mtk-efuse.c | 26 +-
>  1 file changed, 17 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
> index fa7a0f6..c4058b5 100644
> --- a/drivers/nvmem/mtk-efuse.c
> +++ b/drivers/nvmem/mtk-efuse.c
> @@ -18,15 +18,19 @@
>  #include 
>  #include 
>  
> +struct mtk_efuse_priv {
> + void __iomem *base;
> +};
> +
>  static int mtk_reg_read(void *context,
>   unsigned int reg, void *_val, size_t bytes)
>  {
> - void __iomem *base = context;
> + struct mtk_efuse_priv *priv = context;
>   u32 *val = _val;
>   int i = 0, words = bytes / 4;
>  
>   while (words--)
> - *val++ = readl(base + reg + (i++ * 4));
> + *val++ = readl(priv->base + reg + (i++ * 4));
>  
>   return 0;
>  }
> @@ -34,12 +38,12 @@ static int mtk_reg_read(void *context,
>  static int mtk_reg_write(void *context,
>unsigned int reg, void *_val, size_t bytes)
>  {
> - void __iomem *base = context;
> + struct mtk_efuse_priv *priv = context;
>   u32 *val = _val;
>   int i = 0, words = bytes / 4;
>  
>   while (words--)
> - writel(*val++, base + reg + (i++ * 4));
> + writel(*val++, priv->base + reg + (i++ * 4));
>  
>   return 0;
>  }
> @@ -50,19 +54,23 @@ static int mtk_efuse_probe(struct platform_device *pdev)
>   struct resource *res;
>   struct nvmem_device *nvmem;
>   struct nvmem_config econfig = {};
> - void __iomem *base;
> + struct mtk_efuse_priv *priv;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
>  
>   res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - base = devm_ioremap_resource(dev, res);
> - if (IS_ERR(base))
> - return PTR_ERR(base);
> + priv->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(priv->base))
> + return PTR_ERR(priv->base);
>  
>   econfig.stride = 4;
>   econfig.word_size = 4;
>   econfig.reg_read = mtk_reg_read;
>   econfig.reg_write = mtk_reg_write;
>   econfig.size = resource_size(res);
> - econfig.priv = base;
> + econfig.priv = priv;
>   econfig.dev = dev;
>   econfig.owner = THIS_MODULE;
>   nvmem = nvmem_register();