Searched hist:"1 e3057c68b5d8a32a394d3d0324601e3b8888d16" (Results 1 – 2 of 2) sorted by relevance
| /optee_os/core/include/drivers/ |
| H A D | stm32_i2c.h | 1e3057c68b5d8a32a394d3d0324601e3b8888d16 Wed Feb 26 13:32:16 UTC 2025 Etienne Carriere <etienne.carriere@foss.st.com> drivers: stm32_i2c: fallback to interrupt access when no bottom half
Change stm32_i2c driver to allow I2C transfers in interrupt context
before bottom half thread is initialized and after it's released.
This can be needed by PMIC driver to handle PMCI interrupt events
when bottom half thread is not supported by normal wold.
In that case, PMIC driver would need to register its interrupt to
stm32_i2c driver.
Thread accesses to the bus still start by locking the I2C bus mutex.
Before using the bus, the sequence now masks the PMIC interrupt and
polls (with timeout) on I2C bus access atomic lock. This lock
may be held by an I2C transfer currently executing in an interrupt
context. A 100ms timeout is short enough to also allow
debug console traces in the interrupt sequence. Masking the interrupt
before polling the lock ensures no new pending interrupt will interrupt
us (and execute a I2C transfer) while the thread context accesses the
I2C bus.
Interrupt accesses to the bus atomically set/clear the I2C bus access
lock while executing the interrupt sequence.
Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
Signed-off-by: Thomas Bourgoin <thomas.bourgoin@foss.st.com>
Reviewed-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
|
| /optee_os/core/drivers/ |
| H A D | stm32_i2c.c | 1e3057c68b5d8a32a394d3d0324601e3b8888d16 Wed Feb 26 13:32:16 UTC 2025 Etienne Carriere <etienne.carriere@foss.st.com> drivers: stm32_i2c: fallback to interrupt access when no bottom half
Change stm32_i2c driver to allow I2C transfers in interrupt context
before bottom half thread is initialized and after it's released.
This can be needed by PMIC driver to handle PMCI interrupt events
when bottom half thread is not supported by normal wold.
In that case, PMIC driver would need to register its interrupt to
stm32_i2c driver.
Thread accesses to the bus still start by locking the I2C bus mutex.
Before using the bus, the sequence now masks the PMIC interrupt and
polls (with timeout) on I2C bus access atomic lock. This lock
may be held by an I2C transfer currently executing in an interrupt
context. A 100ms timeout is short enough to also allow
debug console traces in the interrupt sequence. Masking the interrupt
before polling the lock ensures no new pending interrupt will interrupt
us (and execute a I2C transfer) while the thread context accesses the
I2C bus.
Interrupt accesses to the bus atomically set/clear the I2C bus access
lock while executing the interrupt sequence.
Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
Signed-off-by: Thomas Bourgoin <thomas.bourgoin@foss.st.com>
Reviewed-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
|