Re: [PATCH v1 1/3] i2c: mux: gpio: Replace custom acpi_get_local_address()

From: Peter Rosin <peda@axentia.se>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Evan Green <evgreen@chromium.org>,
	linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Subject: Re: [PATCH v1 1/3] i2c: mux: gpio: Replace custom acpi_get_local_address()
Date: Thu, 18 Nov 2021 10:36:00 +0100	[thread overview]
Message-ID: <304efdfe-db6e-051e-b61d-e73a8dfa1c53@axentia.se> (raw)
In-Reply-To: <20211115154201.46579-1-andriy.shevchenko@linux.intel.com>

Hi!

On 2021-11-15 16:41, Andy Shevchenko wrote:
> Recently ACPI gained the acpi_get_local_address() API which may be used
> instead of home grown i2c_mux_gpio_get_acpi_adr().
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/i2c/muxes/i2c-mux-gpio.c | 43 ++------------------------------
>  1 file changed, 2 insertions(+), 41 deletions(-)
> 
> diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
> index bac415a52b78..31e6eb1591bb 100644
> --- a/drivers/i2c/muxes/i2c-mux-gpio.c
> +++ b/drivers/i2c/muxes/i2c-mux-gpio.c
> @@ -49,45 +49,6 @@ static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan)
>  	return 0;
>  }
>  
> -#ifdef CONFIG_ACPI
> -
> -static int i2c_mux_gpio_get_acpi_adr(struct device *dev,
> -				     struct fwnode_handle *fwdev,
> -				     unsigned int *adr)
> -
> -{
> -	unsigned long long adr64;
> -	acpi_status status;
> -
> -	status = acpi_evaluate_integer(ACPI_HANDLE_FWNODE(fwdev),
> -				       METHOD_NAME__ADR,
> -				       NULL, &adr64);
> -
> -	if (!ACPI_SUCCESS(status)) {
> -		dev_err(dev, "Cannot get address\n");
> -		return -EINVAL;
> -	}
> -
> -	*adr = adr64;
> -	if (*adr != adr64) {
> -		dev_err(dev, "Address out of range\n");
> -		return -ERANGE;
> -	}

In the conversion, I read it as if we lose this overflow check. Why is that
not a problem?

Cheers,
Peter

> -
> -	return 0;
> -}
> -
> -#else
> -
> -static int i2c_mux_gpio_get_acpi_adr(struct device *dev,
> -				     struct fwnode_handle *fwdev,
> -				     unsigned int *adr)
> -{
> -	return -EINVAL;
> -}
> -
> -#endif
> -
>  static int i2c_mux_gpio_probe_fw(struct gpiomux *mux,
>  				 struct platform_device *pdev)
>  {
> @@ -141,9 +102,9 @@ static int i2c_mux_gpio_probe_fw(struct gpiomux *mux,
>  			fwnode_property_read_u32(child, "reg", values + i);
>  
>  		} else if (is_acpi_node(child)) {
> -			rc = i2c_mux_gpio_get_acpi_adr(dev, child, values + i);
> +			rc = acpi_get_local_address(ACPI_HANDLE_FWNODE(child), values + i);
>  			if (rc)
> -				return rc;
> +				return dev_err_probe(dev, rc, "Cannot get address\n");
>  		}
>  
>  		i++;
> 