Re: [PATCH] kernel/drivers: Remove redundant driver match function

[Finn Thain <fthain@linux-m68k.org>]

On Thu, 5 May 2022, lizhe wrote:

> If there is no driver match function, the driver core assumes that each
> candidate pair (driver, device) matches, see driver_match_device().
> 
> Signed-off-by: lizhe <sensor1010@163.com>

Acked-by: Finn Thain <fthain@linux-m68k.org>
for the nubus changes.

> ---
>  drivers/mfd/mcp-core.c             |  6 ------
>  drivers/nubus/bus.c                |  6 ------
>  drivers/s390/crypto/vfio_ap_drv.c  |  6 ------
>  drivers/scsi/scsi_debug.c          |  7 -------
>  drivers/target/loopback/tcm_loop.c |  7 -------
>  drivers/w1/w1.c                    |  6 ------
>  sound/ac97_bus.c                   | 11 -----------
>  7 files changed, 49 deletions(-)
> 
> diff --git a/drivers/mfd/mcp-core.c b/drivers/mfd/mcp-core.c
> index 2fa592c37c6f..281a9369f2b3 100644
> --- a/drivers/mfd/mcp-core.c
> +++ b/drivers/mfd/mcp-core.c
> @@ -20,11 +20,6 @@
>  #define to_mcp(d)		container_of(d, struct mcp, attached_device)
>  #define to_mcp_driver(d)	container_of(d, struct mcp_driver, drv)
>  
> -static int mcp_bus_match(struct device *dev, struct device_driver *drv)
> -{
> -	return 1;
> -}
> -
>  static int mcp_bus_probe(struct device *dev)
>  {
>  	struct mcp *mcp = to_mcp(dev);
> @@ -43,7 +38,6 @@ static void mcp_bus_remove(struct device *dev)
>  
>  static struct bus_type mcp_bus_type = {
>  	.name		= "mcp",
> -	.match		= mcp_bus_match,
>  	.probe		= mcp_bus_probe,
>  	.remove		= mcp_bus_remove,
>  };
> diff --git a/drivers/nubus/bus.c b/drivers/nubus/bus.c
> index 17fad660032c..72921e4f35f6 100644
> --- a/drivers/nubus/bus.c
> +++ b/drivers/nubus/bus.c
> @@ -14,11 +14,6 @@
>  #define to_nubus_board(d)       container_of(d, struct nubus_board, dev)
>  #define to_nubus_driver(d)      container_of(d, struct nubus_driver, driver)
>  
> -static int nubus_bus_match(struct device *dev, struct device_driver *driver)
> -{
> -	return 1;
> -}
> -
>  static int nubus_device_probe(struct device *dev)
>  {
>  	struct nubus_driver *ndrv = to_nubus_driver(dev->driver);
> @@ -39,7 +34,6 @@ static void nubus_device_remove(struct device *dev)
>  
>  struct bus_type nubus_bus_type = {
>  	.name		= "nubus",
> -	.match		= nubus_bus_match,
>  	.probe		= nubus_device_probe,
>  	.remove		= nubus_device_remove,
>  };
> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
> index 29ebd54f8919..0a662c451f2a 100644
> --- a/drivers/s390/crypto/vfio_ap_drv.c
> +++ b/drivers/s390/crypto/vfio_ap_drv.c
> @@ -172,14 +172,8 @@ static void vfio_ap_matrix_dev_release(struct device *dev)
>  	kfree(matrix_dev);
>  }
>  
> -static int matrix_bus_match(struct device *dev, struct device_driver *drv)
> -{
> -	return 1;
> -}
> -
>  static struct bus_type matrix_bus = {
>  	.name = "matrix",
> -	.match = &matrix_bus_match,
>  };
>  
>  static struct device_driver matrix_driver = {
> diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
> index 592a290e6cfa..8107489b36e8 100644
> --- a/drivers/scsi/scsi_debug.c
> +++ b/drivers/scsi/scsi_debug.c
> @@ -7844,15 +7844,8 @@ static void sdebug_driver_remove(struct device *dev)
>  	scsi_host_put(sdbg_host->shost);
>  }
>  
> -static int pseudo_lld_bus_match(struct device *dev,
> -				struct device_driver *dev_driver)
> -{
> -	return 1;
> -}
> -
>  static struct bus_type pseudo_lld_bus = {
>  	.name = "pseudo",
> -	.match = pseudo_lld_bus_match,
>  	.probe = sdebug_driver_probe,
>  	.remove = sdebug_driver_remove,
>  	.drv_groups = sdebug_drv_groups,
> diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
> index 4407b56aa6d1..eeb63deff94f 100644
> --- a/drivers/target/loopback/tcm_loop.c
> +++ b/drivers/target/loopback/tcm_loop.c
> @@ -83,15 +83,8 @@ static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
>  static int tcm_loop_driver_probe(struct device *);
>  static void tcm_loop_driver_remove(struct device *);
>  
> -static int pseudo_lld_bus_match(struct device *dev,
> -				struct device_driver *dev_driver)
> -{
> -	return 1;
> -}
> -
>  static struct bus_type tcm_loop_lld_bus = {
>  	.name			= "tcm_loop_bus",
> -	.match			= pseudo_lld_bus_match,
>  	.probe			= tcm_loop_driver_probe,
>  	.remove			= tcm_loop_driver_remove,
>  };
> diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
> index f2ae2e563dc5..a6ecfa1b3417 100644
> --- a/drivers/w1/w1.c
> +++ b/drivers/w1/w1.c
> @@ -58,11 +58,6 @@ MODULE_PARM_DESC(slave_ttl,
>  DEFINE_MUTEX(w1_mlock);
>  LIST_HEAD(w1_masters);
>  
> -static int w1_master_match(struct device *dev, struct device_driver *drv)
> -{
> -	return 1;
> -}
> -
>  static int w1_master_probe(struct device *dev)
>  {
>  	return -ENODEV;
> @@ -174,7 +169,6 @@ static int w1_uevent(struct device *dev, struct kobj_uevent_env *env);
>  
>  static struct bus_type w1_bus_type = {
>  	.name = "w1",
> -	.match = w1_master_match,
>  	.uevent = w1_uevent,
>  };
>  
> diff --git a/sound/ac97_bus.c b/sound/ac97_bus.c
> index b4685c53ff11..c7aee8c42c55 100644
> --- a/sound/ac97_bus.c
> +++ b/sound/ac97_bus.c
> @@ -75,19 +75,8 @@ int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id,
>  }
>  EXPORT_SYMBOL_GPL(snd_ac97_reset);
>  
> -/*
> - * Let drivers decide whether they want to support given codec from their
> - * probe method. Drivers have direct access to the struct snd_ac97
> - * structure and may  decide based on the id field amongst other things.
> - */
> -static int ac97_bus_match(struct device *dev, struct device_driver *drv)
> -{
> -	return 1;
> -}
> -
>  struct bus_type ac97_bus_type = {
>  	.name		= "ac97",
> -	.match		= ac97_bus_match,
>  };
>  
>  static int __init ac97_bus_init(void)
>