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-rw-r--r--Documentation/driver-api/cxl/memory-devices.rst8
-rw-r--r--Documentation/driver-api/gpio/consumer.rst10
-rw-r--r--Documentation/driver-api/gpio/driver.rst11
-rw-r--r--Documentation/driver-api/vfio.rst4
4 files changed, 23 insertions, 10 deletions
diff --git a/Documentation/driver-api/cxl/memory-devices.rst b/Documentation/driver-api/cxl/memory-devices.rst
index 487ce4f41d77..50ebcda17ad0 100644
--- a/Documentation/driver-api/cxl/memory-devices.rst
+++ b/Documentation/driver-api/cxl/memory-devices.rst
@@ -36,9 +36,15 @@ CXL Core
.. kernel-doc:: drivers/cxl/cxl.h
:internal:
-.. kernel-doc:: drivers/cxl/core.c
+.. kernel-doc:: drivers/cxl/core/bus.c
:doc: cxl core
+.. kernel-doc:: drivers/cxl/core/pmem.c
+ :doc: cxl pmem
+
+.. kernel-doc:: drivers/cxl/core/regs.c
+ :doc: cxl registers
+
External Interfaces
===================
diff --git a/Documentation/driver-api/gpio/consumer.rst b/Documentation/driver-api/gpio/consumer.rst
index 3366a991b4aa..47869ca8ccf0 100644
--- a/Documentation/driver-api/gpio/consumer.rst
+++ b/Documentation/driver-api/gpio/consumer.rst
@@ -72,6 +72,10 @@ for the GPIO. Values can be:
* GPIOD_OUT_HIGH_OPEN_DRAIN same as GPIOD_OUT_HIGH but also enforce the line
to be electrically used with open drain.
+Note that the initial value is *logical* and the physical line level depends on
+whether the line is configured active high or active low (see
+:ref:`active_low_semantics`).
+
The two last flags are used for use cases where open drain is mandatory, such
as I2C: if the line is not already configured as open drain in the mappings
(see board.txt), then open drain will be enforced anyway and a warning will be
@@ -252,6 +256,8 @@ that can't be accessed from hardIRQ handlers, these calls act the same as the
spinlock-safe calls.
+.. _active_low_semantics:
+
The active low and open drain semantics
---------------------------------------
As a consumer should not have to care about the physical line level, all of the
@@ -309,9 +315,11 @@ work on the raw line value::
void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
-The active low state of a GPIO can also be queried using the following call::
+The active low state of a GPIO can also be queried and toggled using the
+following calls::
int gpiod_is_active_low(const struct gpio_desc *desc)
+ void gpiod_toggle_active_low(struct gpio_desc *desc)
Note that these functions should only be used with great moderation; a driver
should not have to care about the physical line level or open drain semantics.
diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst
index d6b0d779859b..bbc53920d4dd 100644
--- a/Documentation/driver-api/gpio/driver.rst
+++ b/Documentation/driver-api/gpio/driver.rst
@@ -547,13 +547,10 @@ To use the helpers please keep the following in mind:
the irqchip can initialize. E.g. .dev and .can_sleep shall be set up
properly.
-- Nominally set all handlers to handle_bad_irq() in the setup call and pass
- handle_bad_irq() as flow handler parameter in gpiochip_irqchip_add() if it is
- expected for GPIO driver that irqchip .set_type() callback will be called
- before using/enabling each GPIO IRQ. Then set the handler to
- handle_level_irq() and/or handle_edge_irq() in the irqchip .set_type()
- callback depending on what your controller supports and what is requested
- by the consumer.
+- Nominally set gpio_irq_chip.handler to handle_bad_irq. Then, if your irqchip
+ is cascaded, set the handler to handle_level_irq() and/or handle_edge_irq()
+ in the irqchip .set_type() callback depending on what your controller
+ supports and what is requested by the consumer.
Locking IRQ usage
diff --git a/Documentation/driver-api/vfio.rst b/Documentation/driver-api/vfio.rst
index 606eed8823ce..c663b6f97825 100644
--- a/Documentation/driver-api/vfio.rst
+++ b/Documentation/driver-api/vfio.rst
@@ -255,11 +255,13 @@ vfio_unregister_group_dev() respectively::
void vfio_init_group_dev(struct vfio_device *device,
struct device *dev,
const struct vfio_device_ops *ops);
+ void vfio_uninit_group_dev(struct vfio_device *device);
int vfio_register_group_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);
The driver should embed the vfio_device in its own structure and call
-vfio_init_group_dev() to pre-configure it before going to registration.
+vfio_init_group_dev() to pre-configure it before going to registration
+and call vfio_uninit_group_dev() after completing the un-registration.
vfio_register_group_dev() indicates to the core to begin tracking the
iommu_group of the specified dev and register the dev as owned by a VFIO bus
driver. Once vfio_register_group_dev() returns it is possible for userspace to