[PATCH] mfd: altera-sysmgr: Fix physical address storing more

[PATCH] mfd: altera-sysmgr: Fix physical address storing more

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

A recent fix improved the way the resource gets passed to
the low-level accessors, but left one warning that appears
in configurations with a resource_size_t that is wider than
a pointer:

In file included from drivers/mfd/altera-sysmgr.c:19:
drivers/mfd/altera-sysmgr.c: In function 'sysmgr_probe':
drivers/mfd/altera-sysmgr.c:148:40: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  148 |   regmap = devm_regmap_init(dev, NULL, (void *)res->start,
      |                                        ^
include/linux/regmap.h:646:6: note: in definition of macro '__regmap_lockdep_wrapper'
  646 |   fn(__VA_ARGS__, &_key,     \
      |      ^~~~~~~~~~~
drivers/mfd/altera-sysmgr.c:148:12: note: in expansion of macro 'devm_regmap_init'
  148 |   regmap = devm_regmap_init(dev, NULL, (void *)res->start,
      |            ^~~~~~~~~~~~~~~~

I had tried a different approach that would store the address
in the private data as a phys_addr_t, but the easiest solution
now seems to be to add a double cast to shut up the warning.

As the address is passed to an inline assembly, it is guaranteed
to not be wider than a register anyway.

Fixes: d9ca7801b6e5 ("mfd: altera-sysmgr: Fix physical address storing hacks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/mfd/altera-sysmgr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mfd/altera-sysmgr.c b/drivers/mfd/altera-sysmgr.c
index 41076d121dd5..591b300d9095 100644
--- a/drivers/mfd/altera-sysmgr.c
+++ b/drivers/mfd/altera-sysmgr.c
@@ -145,7 +145,8 @@ static int sysmgr_probe(struct platform_device *pdev)
 		sysmgr_config.reg_write = s10_protected_reg_write;
 
 		/* Need physical address for SMCC call */
-		regmap = devm_regmap_init(dev, NULL, (void *)res->start,
+		regmap = devm_regmap_init(dev, NULL,
+					  (void *)(uintptr_t)res->start,
 					  &sysmgr_config);
 	} else {
 		base = devm_ioremap(dev, res->start, resource_size(res));
-- 
2.27.0

Re: [PATCH] mfd: altera-sysmgr: Fix physical address storing more

[Lee Jones]

On Thu, 03 Dec 2020, Arnd Bergmann wrote:

> From: Arnd Bergmann <arnd@arndb.de>
> 
> A recent fix improved the way the resource gets passed to
> the low-level accessors, but left one warning that appears
> in configurations with a resource_size_t that is wider than
> a pointer:
> 
> In file included from drivers/mfd/altera-sysmgr.c:19:
> drivers/mfd/altera-sysmgr.c: In function 'sysmgr_probe':
> drivers/mfd/altera-sysmgr.c:148:40: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>   148 |   regmap = devm_regmap_init(dev, NULL, (void *)res->start,
>       |                                        ^
> include/linux/regmap.h:646:6: note: in definition of macro '__regmap_lockdep_wrapper'
>   646 |   fn(__VA_ARGS__, &_key,     \
>       |      ^~~~~~~~~~~
> drivers/mfd/altera-sysmgr.c:148:12: note: in expansion of macro 'devm_regmap_init'
>   148 |   regmap = devm_regmap_init(dev, NULL, (void *)res->start,
>       |            ^~~~~~~~~~~~~~~~
> 
> I had tried a different approach that would store the address
> in the private data as a phys_addr_t, but the easiest solution
> now seems to be to add a double cast to shut up the warning.
> 
> As the address is passed to an inline assembly, it is guaranteed
> to not be wider than a register anyway.
> 
> Fixes: d9ca7801b6e5 ("mfd: altera-sysmgr: Fix physical address storing hacks")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/mfd/altera-sysmgr.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Applied, thanks.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
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