* [PATCH] MMCI: use _cansleep GPIO functions
@ 2010-09-09 20:31 Linus Walleij
2010-09-11 5:37 ` Rabin Vincent
0 siblings, 1 reply; 9+ messages in thread
From: Linus Walleij @ 2010-09-09 20:31 UTC (permalink / raw)
To: linux-arm-kernel
Currently the kernel is screaming about slowpath at me for the
wp/cd callbacks. Swicth to the _cansleep variants so as to silence
this. Also remove the double-negate in front of the cd GPIO read.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
---
drivers/mmc/host/mmci.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index f0c7313..082abad 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -614,7 +614,7 @@ static int mmci_get_ro(struct mmc_host *mmc)
if (host->gpio_wp == -ENOSYS)
return -ENOSYS;
- return gpio_get_value(host->gpio_wp);
+ return gpio_get_value_cansleep(host->gpio_wp);
}
static int mmci_get_cd(struct mmc_host *mmc)
@@ -629,7 +629,8 @@ static int mmci_get_cd(struct mmc_host *mmc)
status = plat->status(mmc_dev(host->mmc));
} else
- status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
+ status = gpio_get_value_cansleep(host->gpio_cd) ^
+ plat->cd_invert;
/*
* Use positive logic throughout - status is zero for no card,
--
1.6.3.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-09 20:31 [PATCH] MMCI: use _cansleep GPIO functions Linus Walleij
@ 2010-09-11 5:37 ` Rabin Vincent
2010-09-11 11:22 ` Linus Walleij
0 siblings, 1 reply; 9+ messages in thread
From: Rabin Vincent @ 2010-09-11 5:37 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Sep 10, 2010 at 2:01 AM, Linus Walleij
<linus.walleij@stericsson.com> wrote:
> - ? ? ? ? ? ? ? status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
> + ? ? ? ? ? ? ? status = gpio_get_value_cansleep(host->gpio_cd) ^
> + ? ? ? ? ? ? ? ? ? ? ? plat->cd_invert;
Why do you remove the double negation? gpio_get_value*()
can return non-zero values, and we need to make it 1 for the
inversion xor to work.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 5:37 ` Rabin Vincent
@ 2010-09-11 11:22 ` Linus Walleij
2010-09-11 11:31 ` Linus Walleij
2010-09-11 11:32 ` Russell King - ARM Linux
0 siblings, 2 replies; 9+ messages in thread
From: Linus Walleij @ 2010-09-11 11:22 UTC (permalink / raw)
To: linux-arm-kernel
2010/9/11 Rabin Vincent <rabin@rab.in>:
> On Fri, Sep 10, 2010 at 2:01 AM, Linus Walleij
> <linus.walleij@stericsson.com> wrote:
>> - ? ? ? ? ? ? ? status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
>> + ? ? ? ? ? ? ? status = gpio_get_value_cansleep(host->gpio_cd) ^
>> + ? ? ? ? ? ? ? ? ? ? ? plat->cd_invert;
>
> Why do you remove the double negation? ?gpio_get_value*()
> can return non-zero values, and we need to make it 1 for the
> inversion xor to work.
Aha I get it. But !! is a bit hard to parse in head is it not...
Cast a non-zero to C internal bool type, negate it and then
negate the negation so the end result is bool, not just
non-zero. I never saw that idiom before.
I don't know if I'm particularly dumb but it makes my reading
take time.
I'll slam in some intermediate bool or something so it's super
clear what's happening, OK?
Yours,
Linus Walleij
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 11:22 ` Linus Walleij
@ 2010-09-11 11:31 ` Linus Walleij
2010-09-11 11:32 ` Russell King - ARM Linux
1 sibling, 0 replies; 9+ messages in thread
From: Linus Walleij @ 2010-09-11 11:31 UTC (permalink / raw)
To: linux-arm-kernel
2010/9/11 Linus Walleij <linus.ml.walleij@gmail.com>:
> I'll slam in some intermediate bool or something so it's super
> clear what's happening, OK?
Like this (untested):
From: Linus Walleij <linus.walleij@stericsson.com>
Date: Sat, 11 Sep 2010 13:29:04 +0200
Subject: [PATCH] MMCI: use _cansleep GPIO functions
Currently the kernel is screaming about slowpath at me for the
wp/cd callbacks. Swicth to the _cansleep variants so as to silence
this. Also rewrite the double-negate in front of the cd GPIO read
to make it more clear what is happening.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
---
drivers/mmc/host/mmci.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index f0c7313..603d4d5 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -614,7 +614,7 @@ static int mmci_get_ro(struct mmc_host *mmc)
if (host->gpio_wp == -ENOSYS)
return -ENOSYS;
- return gpio_get_value(host->gpio_wp);
+ return gpio_get_value_cansleep(host->gpio_wp);
}
static int mmci_get_cd(struct mmc_host *mmc)
@@ -629,7 +629,9 @@ static int mmci_get_cd(struct mmc_host *mmc)
status = plat->status(mmc_dev(host->mmc));
} else
- status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
+ /* Convert the status to boolean and optionally invert */
+ status = (gpio_get_value_cansleep(host->gpio_cd) ? 1 : 0)
+ ^ plat->cd_invert;
/*
* Use positive logic throughout - status is zero for no card,
--
1.7.2.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 11:22 ` Linus Walleij
2010-09-11 11:31 ` Linus Walleij
@ 2010-09-11 11:32 ` Russell King - ARM Linux
2010-09-11 11:39 ` Linus Walleij
1 sibling, 1 reply; 9+ messages in thread
From: Russell King - ARM Linux @ 2010-09-11 11:32 UTC (permalink / raw)
To: linux-arm-kernel
On Sat, Sep 11, 2010 at 01:22:04PM +0200, Linus Walleij wrote:
> I'll slam in some intermediate bool or something so it's super
> clear what's happening, OK?
No - once you've learnt that !! turns an int into a bool, there's
nothing more that needs to be done.
You'll find !! used throughout the kernel sources.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 11:32 ` Russell King - ARM Linux
@ 2010-09-11 11:39 ` Linus Walleij
2010-09-11 11:40 ` Russell King - ARM Linux
2010-09-11 14:08 ` Sergei Shtylyov
0 siblings, 2 replies; 9+ messages in thread
From: Linus Walleij @ 2010-09-11 11:39 UTC (permalink / raw)
To: linux-arm-kernel
2010/9/11 Russell King - ARM Linux <linux@arm.linux.org.uk>:
> You'll find !! used throughout the kernel sources.
Aha it's a kernel idiom, OK!!
I'll just test it on hardware and I'll put it in the patch tracker.
From: Linus Walleij <linus.walleij@stericsson.com>
Date: Sat, 11 Sep 2010 13:36:20 +0200
Subject: [PATCH] MMCI: use _cansleep GPIO functions
Currently the kernel is screaming about slowpath at me for the
wp/cd callbacks. Swicth to the _cansleep variants so as to silence
this.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
---
drivers/mmc/host/mmci.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index f0c7313..c5fbf19 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -614,7 +614,7 @@ static int mmci_get_ro(struct mmc_host *mmc)
if (host->gpio_wp == -ENOSYS)
return -ENOSYS;
- return gpio_get_value(host->gpio_wp);
+ return gpio_get_value_cansleep(host->gpio_wp);
}
static int mmci_get_cd(struct mmc_host *mmc)
@@ -629,7 +629,8 @@ static int mmci_get_cd(struct mmc_host *mmc)
status = plat->status(mmc_dev(host->mmc));
} else
- status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
+ status = !!gpio_get_value_cansleep(host->gpio_cd)
+ ^ plat->cd_invert;
/*
* Use positive logic throughout - status is zero for no card,
--
1.7.2.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 11:39 ` Linus Walleij
@ 2010-09-11 11:40 ` Russell King - ARM Linux
2010-09-11 14:08 ` Sergei Shtylyov
1 sibling, 0 replies; 9+ messages in thread
From: Russell King - ARM Linux @ 2010-09-11 11:40 UTC (permalink / raw)
To: linux-arm-kernel
On Sat, Sep 11, 2010 at 01:39:04PM +0200, Linus Walleij wrote:
> 2010/9/11 Russell King - ARM Linux <linux@arm.linux.org.uk>:
>
> > You'll find !! used throughout the kernel sources.
>
> Aha it's a kernel idiom, OK!!
>
> I'll just test it on hardware and I'll put it in the patch tracker.
>
> From: Linus Walleij <linus.walleij@stericsson.com>
> Date: Sat, 11 Sep 2010 13:36:20 +0200
> Subject: [PATCH] MMCI: use _cansleep GPIO functions
>
> Currently the kernel is screaming about slowpath at me for the
> wp/cd callbacks. Swicth to the _cansleep variants so as to silence
> this.
You may wish to correct that spelling error.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 11:39 ` Linus Walleij
2010-09-11 11:40 ` Russell King - ARM Linux
@ 2010-09-11 14:08 ` Sergei Shtylyov
2010-09-11 14:11 ` Sergei Shtylyov
1 sibling, 1 reply; 9+ messages in thread
From: Sergei Shtylyov @ 2010-09-11 14:08 UTC (permalink / raw)
To: linux-arm-kernel
Hello.
Linus Walleij wrote:
> From: Linus Walleij <linus.walleij@stericsson.com>
> Date: Sat, 11 Sep 2010 13:36:20 +0200
> Subject: [PATCH] MMCI: use _cansleep GPIO functions
> Currently the kernel is screaming about slowpath at me for the
> wp/cd callbacks. Swicth to the _cansleep variants so as to silence
> this.
> Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
> ---
> drivers/mmc/host/mmci.c | 5 +++--
> 1 files changed, 3 insertions(+), 2 deletions(-)
> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
> index f0c7313..c5fbf19 100644
> --- a/drivers/mmc/host/mmci.c
> +++ b/drivers/mmc/host/mmci.c
[...]
> static int mmci_get_cd(struct mmc_host *mmc)
> @@ -629,7 +629,8 @@ static int mmci_get_cd(struct mmc_host *mmc)
>
> status = plat->status(mmc_dev(host->mmc));
> } else
> - status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
> + status = !!gpio_get_value_cansleep(host->gpio_cd)
> + ^ plat->cd_invert;
Should be no space between ^ and operand, no?
WBR, Sergei
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH] MMCI: use _cansleep GPIO functions
2010-09-11 14:08 ` Sergei Shtylyov
@ 2010-09-11 14:11 ` Sergei Shtylyov
0 siblings, 0 replies; 9+ messages in thread
From: Sergei Shtylyov @ 2010-09-11 14:11 UTC (permalink / raw)
To: linux-arm-kernel
I wrote:
>> From: Linus Walleij <linus.walleij@stericsson.com>
>> Date: Sat, 11 Sep 2010 13:36:20 +0200
>> Subject: [PATCH] MMCI: use _cansleep GPIO functions
>> Currently the kernel is screaming about slowpath at me for the
>> wp/cd callbacks. Swicth to the _cansleep variants so as to silence
>> this.
>> Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
>> ---
>> drivers/mmc/host/mmci.c | 5 +++--
>> 1 files changed, 3 insertions(+), 2 deletions(-)
>> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
>> index f0c7313..c5fbf19 100644
>> --- a/drivers/mmc/host/mmci.c
>> +++ b/drivers/mmc/host/mmci.c
> [...]
>> static int mmci_get_cd(struct mmc_host *mmc)
>> @@ -629,7 +629,8 @@ static int mmci_get_cd(struct mmc_host *mmc)
>>
>> status = plat->status(mmc_dev(host->mmc));
>> } else
>> - status = !!gpio_get_value(host->gpio_cd) ^ plat->cd_invert;
>> + status = !!gpio_get_value_cansleep(host->gpio_cd)
>> + ^ plat->cd_invert;
> Should be no space between ^ and operand, no?
Oops, I've mixed it with ~. Still, I'd have left ^ on the first line.
WBR, Sergei
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2010-09-11 14:11 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
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2010-09-09 20:31 [PATCH] MMCI: use _cansleep GPIO functions Linus Walleij
2010-09-11 5:37 ` Rabin Vincent
2010-09-11 11:22 ` Linus Walleij
2010-09-11 11:31 ` Linus Walleij
2010-09-11 11:32 ` Russell King - ARM Linux
2010-09-11 11:39 ` Linus Walleij
2010-09-11 11:40 ` Russell King - ARM Linux
2010-09-11 14:08 ` Sergei Shtylyov
2010-09-11 14:11 ` Sergei Shtylyov
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