[PATCH master] mfd: syscon: don't register clocked syscon if geting clock fails

[PATCH master] mfd: syscon: don't register clocked syscon if geting clock fails

[Ahmad Fatoum]

When of_syscon_register is called with check_clk=true, it will attempt
to attach the clock. If that fails, the newly allocated syscon is freed,
but a dangling pointer remained in the syscon_list.

Fix this by only registering the syscon in the successful case.

Fixes: b36b7b727192 ("mfd: syscon: clock peripheral if specified in device tree")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 drivers/mfd/syscon.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 3e12123b572e..3c2e1241fdff 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -74,8 +74,6 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
 	syscon_config.val_bits = reg_io_width * 8;
 	syscon_config.max_register = resource_size(&res) - reg_io_width;
 
-	list_add_tail(&syscon->list, &syscon_list);
-
 	syscon->regmap = regmap_init_mmio_clk(NULL, NULL, syscon->base,
 					      &syscon_config);
 
@@ -93,6 +91,8 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
 		}
 	}
 
+	list_add_tail(&syscon->list, &syscon_list);
+
 	return syscon;
 
 err_map:
-- 
2.39.2

Re: [PATCH master] mfd: syscon: don't register clocked syscon if geting clock fails

[Sascha Hauer]

On Thu, Nov 09, 2023 at 12:55:22PM +0100, Ahmad Fatoum wrote:
> When of_syscon_register is called with check_clk=true, it will attempt
> to attach the clock. If that fails, the newly allocated syscon is freed,
> but a dangling pointer remained in the syscon_list.
> 
> Fix this by only registering the syscon in the successful case.
> 
> Fixes: b36b7b727192 ("mfd: syscon: clock peripheral if specified in device tree")
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  drivers/mfd/syscon.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied, thanks

Sascha

> 
> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
> index 3e12123b572e..3c2e1241fdff 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -74,8 +74,6 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
>  	syscon_config.val_bits = reg_io_width * 8;
>  	syscon_config.max_register = resource_size(&res) - reg_io_width;
>  
> -	list_add_tail(&syscon->list, &syscon_list);
> -
>  	syscon->regmap = regmap_init_mmio_clk(NULL, NULL, syscon->base,
>  					      &syscon_config);
>  
> @@ -93,6 +91,8 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
>  		}
>  	}
>  
> +	list_add_tail(&syscon->list, &syscon_list);
> +
>  	return syscon;
>  
>  err_map:
> -- 
> 2.39.2
> 
> 
> 

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |