* [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION [not found] <cover.1572945757.git.matti.vaittinen@fi.rohmeurope.com> @ 2019-11-05 10:16 ` Matti Vaittinen 2019-11-06 5:34 ` Simon Guinot 0 siblings, 1 reply; 5+ messages in thread From: Matti Vaittinen @ 2019-11-05 10:16 UTC (permalink / raw) To: matti.vaittinen, mazziesaccount Cc: Linus Walleij, Bartosz Golaszewski, linux-gpio, linux-kernel It's hard for occasional GPIO code reader/writer to know if values 0/1 equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and GPIO_LINE_DIRECTION_OUT to help them out. Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> --- drivers/gpio/gpio-f7188x.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio-f7188x.c index fdc639f856f1..cadd02993539 100644 --- a/drivers/gpio/gpio-f7188x.c +++ b/drivers/gpio/gpio-f7188x.c @@ -250,7 +250,10 @@ static int f7188x_gpio_get_direction(struct gpio_chip *chip, unsigned offset) superio_exit(sio->addr); - return !(dir & 1 << offset); + if (dir & 1 << offset) + return GPIO_LINE_DIRECTION_OUT; + + return GPIO_LINE_DIRECTION_IN; } static int f7188x_gpio_direction_in(struct gpio_chip *chip, unsigned offset) -- 2.21.0 -- Matti Vaittinen, Linux device drivers ROHM Semiconductors, Finland SWDC Kiviharjunlenkki 1E 90220 OULU FINLAND ~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~ Simon says - in Latin please. ~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~ Thanks to Simon Glass for the translation =] ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION 2019-11-05 10:16 ` [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION Matti Vaittinen @ 2019-11-06 5:34 ` Simon Guinot 2019-11-06 6:44 ` Vaittinen, Matti 0 siblings, 1 reply; 5+ messages in thread From: Simon Guinot @ 2019-11-06 5:34 UTC (permalink / raw) To: Matti Vaittinen Cc: mazziesaccount, Linus Walleij, Bartosz Golaszewski, linux-gpio, linux-kernel [-- Attachment #1: Type: text/plain, Size: 1136 bytes --] On Tue, Nov 05, 2019 at 12:16:03PM +0200, Matti Vaittinen wrote: > It's hard for occasional GPIO code reader/writer to know if values 0/1 > equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and > GPIO_LINE_DIRECTION_OUT to help them out. > > Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> > --- > drivers/gpio/gpio-f7188x.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio-f7188x.c > index fdc639f856f1..cadd02993539 100644 > --- a/drivers/gpio/gpio-f7188x.c > +++ b/drivers/gpio/gpio-f7188x.c > @@ -250,7 +250,10 @@ static int f7188x_gpio_get_direction(struct gpio_chip *chip, unsigned offset) > > superio_exit(sio->addr); > > - return !(dir & 1 << offset); > + if (dir & 1 << offset) > + return GPIO_LINE_DIRECTION_OUT; > + > + return GPIO_LINE_DIRECTION_IN Hi Matti, I am probably missing something but I can't find GPIO_LINE_DIRECTION_IN and GPIO_LINE_DIRECTION_OUT defined anywhere. Besides I am an occasional code reader/writer and I find the original code easy to understand. Simon [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 833 bytes --] ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION 2019-11-06 5:34 ` Simon Guinot @ 2019-11-06 6:44 ` Vaittinen, Matti 2019-11-06 12:38 ` Geert Uytterhoeven 0 siblings, 1 reply; 5+ messages in thread From: Vaittinen, Matti @ 2019-11-06 6:44 UTC (permalink / raw) To: simon.guinot Cc: mazziesaccount, linux-gpio, bgolaszewski, linux-kernel, linus.walleij Morning Simon, On Wed, 2019-11-06 at 06:34 +0100, Simon Guinot wrote: > On Tue, Nov 05, 2019 at 12:16:03PM +0200, Matti Vaittinen wrote: > > It's hard for occasional GPIO code reader/writer to know if values > > 0/1 > > equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and > > GPIO_LINE_DIRECTION_OUT to help them out. > > > > Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> > > --- > > drivers/gpio/gpio-f7188x.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio- > > f7188x.c > > index fdc639f856f1..cadd02993539 100644 > > --- a/drivers/gpio/gpio-f7188x.c > > +++ b/drivers/gpio/gpio-f7188x.c > > @@ -250,7 +250,10 @@ static int f7188x_gpio_get_direction(struct > > gpio_chip *chip, unsigned offset) > > > > superio_exit(sio->addr); > > > > - return !(dir & 1 << offset); > > + if (dir & 1 << offset) > > + return GPIO_LINE_DIRECTION_OUT; > > + > > + return GPIO_LINE_DIRECTION_IN > > Hi Matti, > > I am probably missing something but I can't find > GPIO_LINE_DIRECTION_IN > and GPIO_LINE_DIRECTION_OUT defined anywhere. Sorry. I accidentally sent the patch 01/62 to limited audience - and also messed up the message-ID from the series so threading messages is probably not working :( I did resend the patch adding defines to all reviewers yesterday - title should be "[RESEND PATCH 01/62] gpio: Add definition for GPIO direction". > Besides I am an occasional code reader/writer and I find the original > code easy to understand. Glad to hear that. When I read code: return !(dir & 1 << offset); It's impossible for me to tell if dir having bit at offset 'offset' set means IN or OUT - I know the meaning of code, it checks this bit for in/out - but which dir value is IN and which is OUT? When this is written as: if (dir & 1 << offset) return GPIO_LINE_DIRECTION_OUT; return GPIO_LINE_DIRECTION_IN it get's quite obvious even for me that having the matching bit set means direction to be OUT. Best Regards Matti Vaittinen ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION 2019-11-06 6:44 ` Vaittinen, Matti @ 2019-11-06 12:38 ` Geert Uytterhoeven 2019-11-06 17:26 ` Vaittinen, Matti 0 siblings, 1 reply; 5+ messages in thread From: Geert Uytterhoeven @ 2019-11-06 12:38 UTC (permalink / raw) To: Vaittinen, Matti Cc: simon.guinot, mazziesaccount, linux-gpio, bgolaszewski, linux-kernel, linus.walleij Hi Matti, On Wed, Nov 6, 2019 at 7:45 AM Vaittinen, Matti <Matti.Vaittinen@fi.rohmeurope.com> wrote: > On Wed, 2019-11-06 at 06:34 +0100, Simon Guinot wrote: > > On Tue, Nov 05, 2019 at 12:16:03PM +0200, Matti Vaittinen wrote: > > > It's hard for occasional GPIO code reader/writer to know if values > > > 0/1 > > > equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and > > > GPIO_LINE_DIRECTION_OUT to help them out. > > > > > > Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> > > > --- > > > drivers/gpio/gpio-f7188x.c | 5 ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio- > > > f7188x.c > > > index fdc639f856f1..cadd02993539 100644 > > > --- a/drivers/gpio/gpio-f7188x.c > > > +++ b/drivers/gpio/gpio-f7188x.c > > > @@ -250,7 +250,10 @@ static int f7188x_gpio_get_direction(struct > > > gpio_chip *chip, unsigned offset) > > > > > > superio_exit(sio->addr); > > > > > > - return !(dir & 1 << offset); > > > + if (dir & 1 << offset) > > > + return GPIO_LINE_DIRECTION_OUT; > > > + > > > + return GPIO_LINE_DIRECTION_IN > > > > Hi Matti, > > > > I am probably missing something but I can't find > > GPIO_LINE_DIRECTION_IN > > and GPIO_LINE_DIRECTION_OUT defined anywhere. > > Sorry. I accidentally sent the patch 01/62 to limited audience - and > also messed up the message-ID from the series so threading messages is > probably not working :( I did resend the patch adding defines to all > reviewers yesterday - title should be "[RESEND PATCH 01/62] gpio: Add > definition for GPIO direction". > > > Besides I am an occasional code reader/writer and I find the original > > code easy to understand. > > Glad to hear that. When I read code: > > return !(dir & 1 << offset); > > It's impossible for me to tell if dir having bit at offset 'offset' set > means IN or OUT - I know the meaning of code, it checks this bit for > in/out - but which dir value is IN and which is OUT? > > When this is written as: > > if (dir & 1 << offset) > return GPIO_LINE_DIRECTION_OUT; > > return GPIO_LINE_DIRECTION_IN > > it get's quite obvious even for me that having the matching bit set > means direction to be OUT. "suggest parentheses around... " warning? if (dir & BIT(offset)) ... Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION 2019-11-06 12:38 ` Geert Uytterhoeven @ 2019-11-06 17:26 ` Vaittinen, Matti 0 siblings, 0 replies; 5+ messages in thread From: Vaittinen, Matti @ 2019-11-06 17:26 UTC (permalink / raw) To: geert Cc: mazziesaccount, linux-gpio, simon.guinot, bgolaszewski, linux-kernel, linus.walleij Hello Geert, On Wed, 2019-11-06 at 13:38 +0100, Geert Uytterhoeven wrote: > Hi Matti, > > On Wed, Nov 6, 2019 at 7:45 AM Vaittinen, Matti > <Matti.Vaittinen@fi.rohmeurope.com> wrote: > > On Wed, 2019-11-06 at 06:34 +0100, Simon Guinot wrote: > > > On Tue, Nov 05, 2019 at 12:16:03PM +0200, Matti Vaittinen wrote: > > > > It's hard for occasional GPIO code reader/writer to know if > > > > values > > > > 0/1 > > > > equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and > > > > GPIO_LINE_DIRECTION_OUT to help them out. > > > > > > > > Signed-off-by: Matti Vaittinen < > > > > matti.vaittinen@fi.rohmeurope.com> > > > > --- > > > > drivers/gpio/gpio-f7188x.c | 5 ++++- > > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/gpio/gpio-f7188x.c b/drivers/gpio/gpio- > > > > f7188x.c > > > > index fdc639f856f1..cadd02993539 100644 > > > > --- a/drivers/gpio/gpio-f7188x.c > > > > +++ b/drivers/gpio/gpio-f7188x.c > > > > @@ -250,7 +250,10 @@ static int > > > > f7188x_gpio_get_direction(struct > > > > gpio_chip *chip, unsigned offset) > > > > > > > > superio_exit(sio->addr); > > > > > > > > - return !(dir & 1 << offset); > > > > + if (dir & 1 << offset) > > > > + return GPIO_LINE_DIRECTION_OUT; > > > > + > > > > + return GPIO_LINE_DIRECTION_IN > > > > > > Hi Matti, > > > > > > I am probably missing something but I can't find > > > GPIO_LINE_DIRECTION_IN > > > and GPIO_LINE_DIRECTION_OUT defined anywhere. > > > > Sorry. I accidentally sent the patch 01/62 to limited audience - > > and > > also messed up the message-ID from the series so threading messages > > is > > probably not working :( I did resend the patch adding defines to > > all > > reviewers yesterday - title should be "[RESEND PATCH 01/62] gpio: > > Add > > definition for GPIO direction". > > > > > Besides I am an occasional code reader/writer and I find the > > > original > > > code easy to understand. > > > > Glad to hear that. When I read code: > > > > return !(dir & 1 << offset); > > > > It's impossible for me to tell if dir having bit at offset 'offset' > > set > > means IN or OUT - I know the meaning of code, it checks this bit > > for > > in/out - but which dir value is IN and which is OUT? > > > > When this is written as: > > > > if (dir & 1 << offset) > > return GPIO_LINE_DIRECTION_OUT; > > > > return GPIO_LINE_DIRECTION_IN > > > > it get's quite obvious even for me that having the matching bit set > > means direction to be OUT. > > "suggest parentheses around... " warning? I don't think I saw that. Also, simple test: #include <stdio.h> int main(int argc, char *argv[]) { int offset = argc; if (4 & 1 << offset) printf("foo\n"); printf("%d", !(4 & 1 << offset)); return !(4 & 1 << offset); } and building with gcc -Wall does not show any warnings. nor did compilation for the driver: [mvaittin@localhost linux]$ make ARCH=arm CROSS_COMPILE=${CC} LOADADDR=0x80008000 CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh CHK include/generated/compile.h CC [M] drivers/gpio/gpio-f7188x.o Kernel: arch/arm/boot/Image is ready Kernel: arch/arm/boot/zImage is ready Building modules, stage 2. MODPOST 1282 modules LD [M] drivers/gpio/gpio-f7188x.ko [mvaittin@localhost linux]$ In any case, my intention was to keep the logic exactly same - except for the documented change for cases where I changed bit-position specific return value to 1. Br, Matti Vaittinen ^ permalink raw reply [flat|nested] 5+ messages in thread
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[not found] <cover.1572945757.git.matti.vaittinen@fi.rohmeurope.com>
2019-11-05 10:16 ` [PATCH 13/62] gpio: gpio-f7188x: Use new GPIO_LINE_DIRECTION Matti Vaittinen
2019-11-06 5:34 ` Simon Guinot
2019-11-06 6:44 ` Vaittinen, Matti
2019-11-06 12:38 ` Geert Uytterhoeven
2019-11-06 17:26 ` Vaittinen, Matti
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