[PATCH -next] memory: Convert to DEFINE_SHOW_ATTRIBUTE

[PATCH -next] memory: Convert to DEFINE_SHOW_ATTRIBUTE

[Qinglang Miao]

From: Yongqiang Liu <liuyongqiang13@huawei.com>

Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>
---
 drivers/memory/emif.c               | 22 ++--------------------
 drivers/memory/tegra/tegra124-emc.c | 14 +-------------
 2 files changed, 3 insertions(+), 33 deletions(-)

diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index 58a82eea5..aab8ddad7 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -131,16 +131,7 @@ static int emif_regdump_show(struct seq_file *s, void *unused)
 	return 0;
 }
 
-static int emif_regdump_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, emif_regdump_show, inode->i_private);
-}
-
-static const struct file_operations emif_regdump_fops = {
-	.open			= emif_regdump_open,
-	.read_iter			= seq_read_iter,
-	.release		= single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(emif_regdump);
 
 static int emif_mr4_show(struct seq_file *s, void *unused)
 {
@@ -150,16 +141,7 @@ static int emif_mr4_show(struct seq_file *s, void *unused)
 	return 0;
 }
 
-static int emif_mr4_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, emif_mr4_show, inode->i_private);
-}
-
-static const struct file_operations emif_mr4_fops = {
-	.open			= emif_mr4_open,
-	.read_iter			= seq_read_iter,
-	.release		= single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(emif_mr4);
 
 static int __init_or_module emif_debugfs_init(struct emif_data *emif)
 {
diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c
index 23c44429e..16628df1b 100644
--- a/drivers/memory/tegra/tegra124-emc.c
+++ b/drivers/memory/tegra/tegra124-emc.c
@@ -1059,19 +1059,7 @@ static int tegra_emc_debug_available_rates_show(struct seq_file *s,
 	return 0;
 }
 
-static int tegra_emc_debug_available_rates_open(struct inode *inode,
-						struct file *file)
-{
-	return single_open(file, tegra_emc_debug_available_rates_show,
-			   inode->i_private);
-}
-
-static const struct file_operations tegra_emc_debug_available_rates_fops = {
-	.open = tegra_emc_debug_available_rates_open,
-	.read_iter = seq_read_iter,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(tegra_emc_debug_available_rates);
 
 static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
 {
-- 
2.17.1

Re: [PATCH -next] memory: Convert to DEFINE_SHOW_ATTRIBUTE

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1438 bytes --]

On Thu 2020-07-16 17:03:03, Qinglang Miao wrote:
> From: Yongqiang Liu <liuyongqiang13@huawei.com>
> 
> Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
> 
> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>
> ---
>  drivers/memory/emif.c               | 22 ++--------------------
>  drivers/memory/tegra/tegra124-emc.c | 14 +-------------
>  2 files changed, 3 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
> index 58a82eea5..aab8ddad7 100644
> --- a/drivers/memory/emif.c
> +++ b/drivers/memory/emif.c
> @@ -131,16 +131,7 @@ static int emif_regdump_show(struct seq_file *s, void *unused)
>  	return 0;
>  }
>  
> -static int emif_regdump_open(struct inode *inode, struct file *file)
> -{
> -	return single_open(file, emif_regdump_show, inode->i_private);
> -}
> -
> -static const struct file_operations emif_regdump_fops = {
> -	.open			= emif_regdump_open,
> -	.read_iter			= seq_read_iter,
> -	.release		= single_release,
> -};
> +DEFINE_SHOW_ATTRIBUTE(emif_regdump);

This is not equivalent (and I guess changelog should mention that).

Along with other changes, we get:

        .owner          = THIS_MODULE,
        .llseek         = seq_lseek,

. Is that okay thing to add?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]

Re: [PATCH -next] memory: Convert to DEFINE_SHOW_ATTRIBUTE

[miaoqinglang]

在 2020/7/18 5:14, Pavel Machek 写道:
> On Thu 2020-07-16 17:03:03, Qinglang Miao wrote:
>> From: Yongqiang Liu <liuyongqiang13@huawei.com>
>>
>> Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
>>
>> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>
>> ---
>>   drivers/memory/emif.c               | 22 ++--------------------
>>   drivers/memory/tegra/tegra124-emc.c | 14 +-------------
>>   2 files changed, 3 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
>> index 58a82eea5..aab8ddad7 100644
>> --- a/drivers/memory/emif.c
>> +++ b/drivers/memory/emif.c
>> @@ -131,16 +131,7 @@ static int emif_regdump_show(struct seq_file *s, void *unused)
>>   	return 0;
>>   }
>>   
>> -static int emif_regdump_open(struct inode *inode, struct file *file)
>> -{
>> -	return single_open(file, emif_regdump_show, inode->i_private);
>> -}
>> -
>> -static const struct file_operations emif_regdump_fops = {
>> -	.open			= emif_regdump_open,
>> -	.read_iter			= seq_read_iter,
>> -	.release		= single_release,
>> -};
>> +DEFINE_SHOW_ATTRIBUTE(emif_regdump);
> 
> This is not equivalent (and I guess changelog should mention that).
> 
> Along with other changes, we get:
> 
>          .owner          = THIS_MODULE,
>          .llseek         = seq_lseek,
> 
> . Is that okay thing to add?
> 									Pavel
> 
Hi Pavel,

​You're right, I should of mention it in changelog.

​There's no impact theoretically with these two changes. Here's my thoughs:

1. The llseek method is used to change the current read/write position 
in a file which can be ignored if you don't use it.
2. The owner is not even a method. Instead, it is a pointer to the 
module that “owns” this structure; it is used by the kernel to maintain 
the module's usage count which I believe can be ignored.

If you don't mind I can send a new patch with more specific changelog.

​Thanks.

Qinglang

.

Re: [PATCH -next] memory: Convert to DEFINE_SHOW_ATTRIBUTE

[miaoqinglang]

在 2020/7/18 5:14, Pavel Machek 写道:
> On Thu 2020-07-16 17:03:03, Qinglang Miao wrote:
>> From: Yongqiang Liu <liuyongqiang13@huawei.com>
>>
>> Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
>>
>> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>
>> ---
>>   drivers/memory/emif.c               | 22 ++--------------------
>>   drivers/memory/tegra/tegra124-emc.c | 14 +-------------
>>   2 files changed, 3 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
>> index 58a82eea5..aab8ddad7 100644
>> --- a/drivers/memory/emif.c
>> +++ b/drivers/memory/emif.c
>> @@ -131,16 +131,7 @@ static int emif_regdump_show(struct seq_file *s, void *unused)
>>   	return 0;
>>   }
>>   
>> -static int emif_regdump_open(struct inode *inode, struct file *file)
>> -{
>> -	return single_open(file, emif_regdump_show, inode->i_private);
>> -}
>> -
>> -static const struct file_operations emif_regdump_fops = {
>> -	.open			= emif_regdump_open,
>> -	.read_iter			= seq_read_iter,
>> -	.release		= single_release,
>> -};
>> +DEFINE_SHOW_ATTRIBUTE(emif_regdump);
> 
> This is not equivalent (and I guess changelog should mention that).
> 
> Along with other changes, we get:
> 
>          .owner          = THIS_MODULE,
>          .llseek         = seq_lseek,
> 
> . Is that okay thing to add?
> 									Pavel
> 
Hi Pavel,

I've sent a new patch against linux-next(20200917), and it can
be applied to mainline cleanly now.

And your concerns are explained in commit log.

Thanks.