[PATCH 04/12] nvmem: qfprom: fix different address space warnings of sparse

From: srinivas . kandagatla
Date: Mon Oct 09 2017 - 09:29:46 EST


From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>

Fix the following sparse warnings:

drivers/nvmem/qfprom.c:23:30: warning: incorrect type in initializer (different address spaces)
drivers/nvmem/qfprom.c:23:30: expected void [noderef] <asn:2>*base
drivers/nvmem/qfprom.c:23:30: got void *context
drivers/nvmem/qfprom.c:36:30: warning: incorrect type in initializer (different address spaces)
drivers/nvmem/qfprom.c:36:30: expected void [noderef] <asn:2>*base
drivers/nvmem/qfprom.c:36:30: got void *context
drivers/nvmem/qfprom.c:76:22: warning: incorrect type in assignment (different address spaces)
drivers/nvmem/qfprom.c:76:22: expected void *static [toplevel] [assigned] priv
drivers/nvmem/qfprom.c:76:22: got void [noderef] <asn:2>*[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 <yamada.masahiro@xxxxxxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/nvmem/qfprom.c | 26 +++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index 2bdb6c389328..b96730e99580 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -17,15 +17,19 @@
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>

+struct qfprom_priv {
+ void __iomem *base;
+};
+
static int qfprom_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
- void __iomem *base = context;
+ struct qfprom_priv *priv = context;
u8 *val = _val;
int i = 0, words = bytes;

while (words--)
- *val++ = readb(base + reg + i++);
+ *val++ = readb(priv->base + reg + i++);

return 0;
}
@@ -33,12 +37,12 @@ static int qfprom_reg_read(void *context,
static int qfprom_reg_write(void *context,
unsigned int reg, void *_val, size_t bytes)
{
- void __iomem *base = context;
+ struct qfprom_priv *priv = context;
u8 *val = _val;
int i = 0, words = bytes;

while (words--)
- writeb(*val++, base + reg + i++);
+ writeb(*val++, priv->base + reg + i++);

return 0;
}
@@ -64,16 +68,20 @@ static int qfprom_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct resource *res;
struct nvmem_device *nvmem;
- void __iomem *base;
+ struct qfprom_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.size = resource_size(res);
econfig.dev = dev;
- econfig.priv = base;
+ econfig.priv = priv;

nvmem = nvmem_register(&econfig);
if (IS_ERR(nvmem))
--
2.11.0