| Message ID | ZsPtCPwnXAyHG2Jq@google.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next] nfc: st95hf: switch to using sleeping variants of gpiod API | expand |
On 8/20/24 03:10, Dmitry Torokhov wrote: > The driver does not not use gpiod API calls in an atomic context. Switch please remove one "not" > to gpiod_set_value_cansleep() calls to allow using the driver with GPIO > controllers that might need process context to operate. > > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Code is fine, but why not as a fix? > --- > drivers/nfc/st95hf/core.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/nfc/st95hf/core.c b/drivers/nfc/st95hf/core.c > index ffe5b4eab457..5b3451fc4491 100644 > --- a/drivers/nfc/st95hf/core.c > +++ b/drivers/nfc/st95hf/core.c > @@ -450,19 +450,19 @@ static int st95hf_select_protocol(struct st95hf_context *stcontext, int type) > static void st95hf_send_st95enable_negativepulse(struct st95hf_context *st95con) > { > /* First make irq_in pin high */ > - gpiod_set_value(st95con->enable_gpiod, HIGH); > + gpiod_set_value_cansleep(st95con->enable_gpiod, HIGH); > > /* wait for 1 milisecond */ > usleep_range(1000, 2000); > > /* Make irq_in pin low */ > - gpiod_set_value(st95con->enable_gpiod, LOW); > + gpiod_set_value_cansleep(st95con->enable_gpiod, LOW); > > /* wait for minimum interrupt pulse to make st95 active */ > usleep_range(1000, 2000); > > /* At end make it high */ > - gpiod_set_value(st95con->enable_gpiod, HIGH); > + gpiod_set_value_cansleep(st95con->enable_gpiod, HIGH); > } > > /*
On Tue, Aug 20, 2024 at 10:10:37AM +0200, Przemek Kitszel wrote: > On 8/20/24 03:10, Dmitry Torokhov wrote: > > The driver does not not use gpiod API calls in an atomic context. Switch > > please remove one "not" > > > to gpiod_set_value_cansleep() calls to allow using the driver with GPIO > > controllers that might need process context to operate. > > > > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> > > Code is fine, but why not as a fix? Why would this be a fix? What is broken? Andrew
On Mon, 19 Aug 2024 18:10:32 -0700 Dmitry Torokhov wrote: > The driver does not not use gpiod API calls in an atomic context. Switch > to gpiod_set_value_cansleep() calls to allow using the driver with GPIO > controllers that might need process context to operate. Could you explain why? Are you using this device? Is it part of some larger effort to remove an API?
On Tue, Aug 20, 2024 at 08:26:14AM -0700, Jakub Kicinski wrote: > On Mon, 19 Aug 2024 18:10:32 -0700 Dmitry Torokhov wrote: > > The driver does not not use gpiod API calls in an atomic context. Switch > > to gpiod_set_value_cansleep() calls to allow using the driver with GPIO > > controllers that might need process context to operate. > > Could you explain why? Are you using this device? Is it part of some > larger effort to remove an API? Because it is better to use sleeping variants of gpiod API unless the call is in atomic context, so it is basic code hygiene. We do not want other drivers to copy the behavior. I was going through my WIP patches and decided to sent it out. Originally it was part of overall transition of the driver to gpiod API, but Andy Shevchenko beat me to it, so movement to gpiod_set_value_cansleep() is all that is left. Thanks.
On Tue, Aug 20, 2024 at 03:53:21PM +0200, Andrew Lunn wrote: > On Tue, Aug 20, 2024 at 10:10:37AM +0200, Przemek Kitszel wrote: > > On 8/20/24 03:10, Dmitry Torokhov wrote: > > > The driver does not not use gpiod API calls in an atomic context. Switch > > > > please remove one "not" > > > > > to gpiod_set_value_cansleep() calls to allow using the driver with GPIO > > > controllers that might need process context to operate. > > > > > > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> > > > > Code is fine, but why not as a fix? > > Why would this be a fix? What is broken? No, this is not a fix but a tiny enhancement. As far as I know no existing devices actually require it. Thanks.
diff --git a/drivers/nfc/st95hf/core.c b/drivers/nfc/st95hf/core.c index ffe5b4eab457..5b3451fc4491 100644 --- a/drivers/nfc/st95hf/core.c +++ b/drivers/nfc/st95hf/core.c @@ -450,19 +450,19 @@ static int st95hf_select_protocol(struct st95hf_context *stcontext, int type) static void st95hf_send_st95enable_negativepulse(struct st95hf_context *st95con) { /* First make irq_in pin high */ - gpiod_set_value(st95con->enable_gpiod, HIGH); + gpiod_set_value_cansleep(st95con->enable_gpiod, HIGH); /* wait for 1 milisecond */ usleep_range(1000, 2000); /* Make irq_in pin low */ - gpiod_set_value(st95con->enable_gpiod, LOW); + gpiod_set_value_cansleep(st95con->enable_gpiod, LOW); /* wait for minimum interrupt pulse to make st95 active */ usleep_range(1000, 2000); /* At end make it high */ - gpiod_set_value(st95con->enable_gpiod, HIGH); + gpiod_set_value_cansleep(st95con->enable_gpiod, HIGH); } /*
The driver does not not use gpiod API calls in an atomic context. Switch to gpiod_set_value_cansleep() calls to allow using the driver with GPIO controllers that might need process context to operate. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> --- drivers/nfc/st95hf/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)