On 2/18/20 7:13 PM, Marek Vasut wrote:
On 2/18/20 7:10 PM, Alexandre Torgue wrote:
Hi Marek
Hi,
On 2/18/20 5:25 PM, Marek Vasut wrote:
On 2/18/20 2:12 PM, Alexandre Torgue wrote:
This series adds the possibility to handle gpio interrupts on level.
GPIO hardware block is directly linked to EXTI block but EXTI handles
external interrupts only on edge. To be able to handle GPIO interrupt on
level a "hack" is done in gpio irq chip: parent interrupt (exti irq
chip)
is retriggered following interrupt type and gpio line value.
In exti irq chip, retrigger ops function is added.
btw. this might be unrelated, but is it possible to have e.g. gpioC2 set
as trigger-level-low and gpioD2 set as trigger-edge-falling ? It seems
8eb2dfee9fb1 ("pinctrl: stm32: add lock mechanism for irqmux selection")
prevents that.
No it's not possible. Each gpio line doesn't have a dedicated Exti line
Each Exti line is muxing between gpio banks.
OK, that confirms my assumption.
Mapping is done as following:
EXTI0 = A0 or B0 or C0 .... or Z0 : selected by Mux
EXTI1 = A1 or B1 or C1 ....or Z1 : selected by Mux
EXTI2 = A2 or B2 or C2 ....or Z2 : selected by Mux
...
Is it at least possible to have IRQs of the same type on the same exti
line? E.g. gpioA2 of trigger-edge-falling and gpioB2 trigger-edge-falling ?
Sorry I don't catch your point. If you already succeed to get gpioA2,
then you will failed to get gpioB2 but looking at function call stack we
could get an other issue.
Lets take example where you succeed to get gpioa2 as interrupt (using
interrupt bindings) and now you try to do the same for gpiob2, you will
have (roughly):
stm32_gpio_irq_request_resources (for gpiob2) --> succeed
stm32_gpio_set_type
|
|--> stm32_exti_set_type type -> change exti line 2 trigger registers
with gpiob2 binding.
stm32_gpio_domain_activate --> failed as exti line2 is already used
by gpioa2.
So as stm32_gpio_set_type is called before checking than exti line is
available, type could be changed and behavior of gpioa2 interrupt broken.
Solution would be to move the exti line mux check from
stm32_gpio_domain_activate to stm32_gpio_irq_request_resources callback.
Regards
Alex
