Re: [PATCH v2 2/2] ASoC: Intel: Atom: add quirk for CHT w/ RT5645

[Takashi Iwai <tiwai@suse.de>]

On Mon, 04 Jul 2016 18:53:48 +0200,
Stephen Just wrote:
> 
> The Surface 3 uses an RT5645 audio codec, but the ACPI
> identifier used is that for the RT5640. Use a DMI match
> to override the driver_data provided by ACPI to workaround
> ID conflict.
> 
> Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Cc: Mark Brown <broonie@kernel.org>
> Cc: Vinod Koul <vinod.koul@intel.com>
> Signed-off-by: Stephen Just <stephenjust@gmail.com>
> ---
>  sound/soc/intel/atom/sst/sst_acpi.c     | 29 ++++++++++++++++++++++++++++-
>  sound/soc/intel/boards/cht_bsw_rt5645.c |  1 +
>  2 files changed, 29 insertions(+), 1 deletion(-)
> 
> v1 -> v2: No change
> 
> diff --git a/sound/soc/intel/atom/sst/sst_acpi.c b/sound/soc/intel/atom/sst/sst_acpi.c
> index 3bc4b63..ef40608 100644
> --- a/sound/soc/intel/atom/sst/sst_acpi.c
> +++ b/sound/soc/intel/atom/sst/sst_acpi.c
> @@ -19,6 +19,7 @@
>   */
>  
>  #include <linux/module.h>
> +#include <linux/dmi.h>
>  #include <linux/fs.h>
>  #include <linux/interrupt.h>
>  #include <linux/slab.h>
> @@ -131,6 +132,8 @@ static struct sst_platform_info chv_platform_data = {
>  	.platform = "sst-mfld-platform",
>  };
>  
> +static const struct dmi_system_id dmi_platform_quirk_table[];
> +
>  static int sst_platform_get_resources(struct intel_sst_drv *ctx)
>  {
>  	struct resource *rsrc;
> @@ -224,6 +227,7 @@ static int sst_acpi_probe(struct platform_device *pdev)
>  	struct platform_device *mdev;
>  	struct platform_device *plat_dev;
>  	struct sst_platform_info *pdata;
> +	const struct dmi_system_id *dmi_match;
>  	unsigned int dev_id;
>  
>  	id = acpi_match_device(dev->driver->acpi_match_table, dev);
> @@ -231,7 +235,13 @@ static int sst_acpi_probe(struct platform_device *pdev)
>  		return -ENODEV;
>  	dev_dbg(dev, "for %s", id->id);
>  
> -	mach = (struct sst_acpi_mach *)id->driver_data;
> +	/* check for quirk when getting driver_data */
> +	dmi_match = dmi_first_match(dmi_platform_quirk_table);
> +	if (dmi_match)
> +		mach = (struct sst_acpi_mach *)dmi_match->driver_data;

dmi_system_id.driver_data is void*, so you need no cast here (unlike
acpi_device_id below).


> +	else
> +		mach = (struct sst_acpi_mach *)id->driver_data;
> +
>  	mach = sst_acpi_find_machine(mach);
>  	if (mach == NULL) {
>  		dev_err(dev, "No matching machine driver found\n");
> @@ -345,7 +355,24 @@ static struct sst_acpi_mach sst_acpi_chv[] = {
>  	/* some CHT-T platforms rely on RT5640, use Baytrail machine driver */
>  	{"10EC5640", "bytcr_rt5640", "intel/fw_sst_22a8.bin", "bytcr_rt5640", NULL,
>  						&chv_platform_data },
> +	{},
> +};
>  
> +static struct sst_acpi_mach sst_acpi_chv_quirk[] = {
> +	/* some CHT-T platforms rely on RT5645 but use the ID from RT5640 */
> +	{"10EC5640", "cht-bsw-rt5645", "intel/fw_sst_22a8.bin", "cht-bsw", NULL,
> +						&chv_platform_data },
> +	{},
> +};
> +
> +static const struct dmi_system_id dmi_platform_quirk_table[] = {
> +	{
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "Surface 3"),
> +		},
> +		.driver_data = (unsigned long *) &sst_acpi_chv_quirk,

Why cast to unsigned long pointer...?


Takashi