The ioctl helpers are well documented, except they are not plugged in
the Documentation. So fix up the minor issues in the kernel-doc and plug
it in.
The minor issues include:
* bad \t on every line (sphinx misinterprets the description otherwise)
* missing colon after Return
* superfluous \n after the comment
* make some struct members and constants a hyperlink
* and so on
Perhaps better to use --word-diff if one wants to see the "real"
changes.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
---
Documentation/driver-api/tty/index.rst | 1 +
Documentation/driver-api/tty/tty_ioctl.rst | 7 +
drivers/tty/tty_ioctl.c | 218 ++++++++++-----------
3 files changed, 115 insertions(+), 111 deletions(-)
create mode 100644 Documentation/driver-api/tty/tty_ioctl.rst
diff --git a/Documentation/driver-api/tty/index.rst b/Documentation/driver-api/tty/index.rst
index 2d32606a4278..b490da11f257 100644
--- a/Documentation/driver-api/tty/index.rst
+++ b/Documentation/driver-api/tty/index.rst
@@ -36,6 +36,7 @@ In-detail description of the named TTY structures is in separate documents:
tty_struct
tty_ldisc
tty_buffer
+ tty_ioctl
tty_internals
Writing TTY Driver
diff --git a/Documentation/driver-api/tty/tty_ioctl.rst b/Documentation/driver-api/tty/tty_ioctl.rst
new file mode 100644
index 000000000000..9b0be79fc15e
--- /dev/null
+++ b/Documentation/driver-api/tty/tty_ioctl.rst
@@ -0,0 +1,7 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=================
+TTY IOCTL Helpers
+=================
+
+.. kernel-doc:: drivers/tty/tty_ioctl.c
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index fb2f1ac5172f..42c793e9d131 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -38,16 +38,13 @@
#define TERMIOS_TERMIO BIT(2)
#define TERMIOS_OLD BIT(3)
-
/**
- * tty_chars_in_buffer - characters pending
- * @tty: terminal
+ * tty_chars_in_buffer - characters pending
+ * @tty: terminal
*
- * Return the number of bytes of data in the device private
- * output queue. If no private method is supplied there is assumed
- * to be no queue on the device.
+ * Returns: the number of bytes of data in the device private output queue. If
+ * no private method is supplied there is assumed to be no queue on the device.
*/
-
unsigned int tty_chars_in_buffer(struct tty_struct *tty)
{
if (tty->ops->chars_in_buffer)
@@ -57,16 +54,15 @@ unsigned int tty_chars_in_buffer(struct tty_struct *tty)
EXPORT_SYMBOL(tty_chars_in_buffer);
/**
- * tty_write_room - write queue space
- * @tty: terminal
+ * tty_write_room - write queue space
+ * @tty: terminal
*
- * Return the number of bytes that can be queued to this device
- * at the present time. The result should be treated as a guarantee
- * and the driver cannot offer a value it later shrinks by more than
- * the number of bytes written. If no method is provided 2K is always
- * returned and data may be lost as there will be no flow control.
+ * Returns: the number of bytes that can be queued to this device at the present
+ * time. The result should be treated as a guarantee and the driver cannot
+ * offer a value it later shrinks by more than the number of bytes written. If
+ * no method is provided, 2K is always returned and data may be lost as there
+ * will be no flow control.
*/
-
unsigned int tty_write_room(struct tty_struct *tty)
{
if (tty->ops->write_room)
@@ -76,12 +72,12 @@ unsigned int tty_write_room(struct tty_struct *tty)
EXPORT_SYMBOL(tty_write_room);
/**
- * tty_driver_flush_buffer - discard internal buffer
- * @tty: terminal
+ * tty_driver_flush_buffer - discard internal buffer
+ * @tty: terminal
*
- * Discard the internal output buffer for this device. If no method
- * is provided then either the buffer cannot be hardware flushed or
- * there is no buffer driver side.
+ * Discard the internal output buffer for this device. If no method is provided,
+ * then either the buffer cannot be hardware flushed or there is no buffer
+ * driver side.
*/
void tty_driver_flush_buffer(struct tty_struct *tty)
{
@@ -91,18 +87,17 @@ void tty_driver_flush_buffer(struct tty_struct *tty)
EXPORT_SYMBOL(tty_driver_flush_buffer);
/**
- * tty_unthrottle - flow control
- * @tty: terminal
+ * tty_unthrottle - flow control
+ * @tty: terminal
*
- * Indicate that a tty may continue transmitting data down the stack.
- * Takes the termios rwsem to protect against parallel throttle/unthrottle
- * and also to ensure the driver can consistently reference its own
- * termios data at this point when implementing software flow control.
+ * Indicate that a @tty may continue transmitting data down the stack. Takes
+ * the &tty_struct->termios_rwsem to protect against parallel
+ * throttle/unthrottle and also to ensure the driver can consistently reference
+ * its own termios data at this point when implementing software flow control.
*
- * Drivers should however remember that the stack can issue a throttle,
- * then change flow control method, then unthrottle.
+ * Drivers should however remember that the stack can issue a throttle, then
+ * change flow control method, then unthrottle.
*/
-
void tty_unthrottle(struct tty_struct *tty)
{
down_write(&tty->termios_rwsem);
@@ -115,16 +110,15 @@ void tty_unthrottle(struct tty_struct *tty)
EXPORT_SYMBOL(tty_unthrottle);
/**
- * tty_throttle_safe - flow control
- * @tty: terminal
+ * tty_throttle_safe - flow control
+ * @tty: terminal
*
- * Indicate that a tty should stop transmitting data down the stack.
- * tty_throttle_safe will only attempt throttle if tty->flow_change is
- * TTY_THROTTLE_SAFE. Prevents an accidental throttle due to race
- * conditions when throttling is conditional on factors evaluated prior to
- * throttling.
+ * Indicate that a @tty should stop transmitting data down the stack.
+ * tty_throttle_safe() will only attempt throttle if @tty->flow_change is
+ * %TTY_THROTTLE_SAFE. Prevents an accidental throttle due to race conditions
+ * when throttling is conditional on factors evaluated prior to throttling.
*
- * Returns true if tty is throttled (or was already throttled)
+ * Returns: %true if @tty is throttled (or was already throttled)
*/
bool tty_throttle_safe(struct tty_struct *tty)
{
@@ -146,15 +140,15 @@ bool tty_throttle_safe(struct tty_struct *tty)
}
/**
- * tty_unthrottle_safe - flow control
- * @tty: terminal
+ * tty_unthrottle_safe - flow control
+ * @tty: terminal
*
- * Similar to tty_unthrottle() but will only attempt unthrottle
- * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental
- * unthrottle due to race conditions when unthrottling is conditional
- * on factors evaluated prior to unthrottling.
+ * Similar to tty_unthrottle() but will only attempt unthrottle if
+ * @tty->flow_change is %TTY_UNTHROTTLE_SAFE. Prevents an accidental unthrottle
+ * due to race conditions when unthrottling is conditional on factors evaluated
+ * prior to unthrottling.
*
- * Returns true if tty is unthrottled (or was already unthrottled)
+ * Returns: %true if @tty is unthrottled (or was already unthrottled)
*/
bool tty_unthrottle_safe(struct tty_struct *tty)
{
@@ -176,14 +170,14 @@ bool tty_unthrottle_safe(struct tty_struct *tty)
}
/**
- * tty_wait_until_sent - wait for I/O to finish
- * @tty: tty we are waiting for
- * @timeout: how long we will wait
+ * tty_wait_until_sent - wait for I/O to finish
+ * @tty: tty we are waiting for
+ * @timeout: how long we will wait
*
- * Wait for characters pending in a tty driver to hit the wire, or
- * for a timeout to occur (eg due to flow control)
+ * Wait for characters pending in a tty driver to hit the wire, or for a
+ * timeout to occur (eg due to flow control).
*
- * Locking: none
+ * Locking: none
*/
void tty_wait_until_sent(struct tty_struct *tty, long timeout)
@@ -229,16 +223,15 @@ static void unset_locked_termios(struct tty_struct *tty, const struct ktermios *
}
/**
- * tty_termios_copy_hw - copy hardware settings
- * @new: New termios
- * @old: Old termios
+ * tty_termios_copy_hw - copy hardware settings
+ * @new: new termios
+ * @old: old termios
*
- * Propagate the hardware specific terminal setting bits from
- * the old termios structure to the new one. This is used in cases
- * where the hardware does not support reconfiguration or as a helper
- * in some cases where only minimal reconfiguration is supported
+ * Propagate the hardware specific terminal setting bits from the @old termios
+ * structure to the @new one. This is used in cases where the hardware does not
+ * support reconfiguration or as a helper in some cases where only minimal
+ * reconfiguration is supported.
*/
-
void tty_termios_copy_hw(struct ktermios *new, const struct ktermios *old)
{
/* The bits a dumb device handles in software. Smart devices need
@@ -251,14 +244,15 @@ void tty_termios_copy_hw(struct ktermios *new, const struct ktermios *old)
EXPORT_SYMBOL(tty_termios_copy_hw);
/**
- * tty_termios_hw_change - check for setting change
- * @a: termios
- * @b: termios to compare
+ * tty_termios_hw_change - check for setting change
+ * @a: termios
+ * @b: termios to compare
*
- * Check if any of the bits that affect a dumb device have changed
- * between the two termios structures, or a speed change is needed.
+ * Check if any of the bits that affect a dumb device have changed between the
+ * two termios structures, or a speed change is needed.
+ *
+ * Returns: %true if change is needed
*/
-
bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b)
{
if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed)
@@ -270,11 +264,10 @@ bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b)
EXPORT_SYMBOL(tty_termios_hw_change);
/**
- * tty_get_char_size - get size of a character
- * @cflag: termios cflag value
+ * tty_get_char_size - get size of a character
+ * @cflag: termios cflag value
*
- * Get the size (in bits) of a character depending on @cflag's %CSIZE
- * setting.
+ * Returns: size (in bits) of a character depending on @cflag's %CSIZE setting
*/
unsigned char tty_get_char_size(unsigned int cflag)
{
@@ -293,13 +286,14 @@ unsigned char tty_get_char_size(unsigned int cflag)
EXPORT_SYMBOL_GPL(tty_get_char_size);
/**
- * tty_get_frame_size - get size of a frame
- * @cflag: termios cflag value
+ * tty_get_frame_size - get size of a frame
+ * @cflag: termios cflag value
*
- * Get the size (in bits) of a frame depending on @cflag's %CSIZE, %CSTOPB,
- * and %PARENB setting. The result is a sum of character size, start and
- * stop bits -- one bit each -- second stop bit (if set), and parity bit
- * (if set).
+ * Get the size (in bits) of a frame depending on @cflag's %CSIZE, %CSTOPB, and
+ * %PARENB setting. The result is a sum of character size, start and stop bits
+ * -- one bit each -- second stop bit (if set), and parity bit (if set).
+ *
+ * Returns: size (in bits) of a frame depending on @cflag's setting.
*/
unsigned char tty_get_frame_size(unsigned int cflag)
{
@@ -317,16 +311,15 @@ unsigned char tty_get_frame_size(unsigned int cflag)
EXPORT_SYMBOL_GPL(tty_get_frame_size);
/**
- * tty_set_termios - update termios values
- * @tty: tty to update
- * @new_termios: desired new value
+ * tty_set_termios - update termios values
+ * @tty: tty to update
+ * @new_termios: desired new value
*
- * Perform updates to the termios values set on this terminal.
- * A master pty's termios should never be set.
+ * Perform updates to the termios values set on this @tty. A master pty's
+ * termios should never be set.
*
- * Locking: termios_rwsem
+ * Locking: &tty_struct->termios_rwsem
*/
-
int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
{
struct ktermios old_termios;
@@ -439,18 +432,19 @@ __weak int kernel_termios_to_user_termios(struct termios __user *u,
#endif /* TCGETS2 */
/**
- * set_termios - set termios values for a tty
- * @tty: terminal device
- * @arg: user data
- * @opt: option information
+ * set_termios - set termios values for a tty
+ * @tty: terminal device
+ * @arg: user data
+ * @opt: option information
*
- * Helper function to prepare termios data and run necessary other
- * functions before using tty_set_termios to do the actual changes.
+ * Helper function to prepare termios data and run necessary other functions
+ * before using tty_set_termios() to do the actual changes.
*
- * Locking:
- * Called functions take ldisc and termios_rwsem locks
+ * Locking: called functions take &tty_struct->ldisc_sem and
+ * &tty_struct->termios_rwsem locks
+ *
+ * Returns: 0 on success, an error otherwise
*/
-
static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
{
struct ktermios tmp_termios;
@@ -622,16 +616,16 @@ static void set_sgflags(struct ktermios *termios, int flags)
}
/**
- * set_sgttyb - set legacy terminal values
- * @tty: tty structure
- * @sgttyb: pointer to old style terminal structure
+ * set_sgttyb - set legacy terminal values
+ * @tty: tty structure
+ * @sgttyb: pointer to old style terminal structure
*
- * Updates a terminal from the legacy BSD style terminal information
- * structure.
+ * Updates a terminal from the legacy BSD style terminal information structure.
*
- * Locking: termios_rwsem
+ * Locking: &tty_struct->termios_rwsem
+ *
+ * Returns: 0 on success, an error otherwise
*/
-
static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
{
int retval;
@@ -733,14 +727,17 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
#endif
/**
- * tty_change_softcar - carrier change ioctl helper
- * @tty: tty to update
- * @enable: enable/disable CLOCAL
+ * tty_change_softcar - carrier change ioctl helper
+ * @tty: tty to update
+ * @enable: enable/disable %CLOCAL
*
- * Perform a change to the CLOCAL state and call into the driver
- * layer to make it visible. All done with the termios rwsem
+ * Perform a change to the %CLOCAL state and call into the driver layer to make
+ * it visible.
+ *
+ * Locking: &tty_struct->termios_rwsem.
+ *
+ * Returns: 0 on success, an error otherwise
*/
-
static int tty_change_softcar(struct tty_struct *tty, bool enable)
{
int ret = 0;
@@ -760,16 +757,15 @@ static int tty_change_softcar(struct tty_struct *tty, bool enable)
}
/**
- * tty_mode_ioctl - mode related ioctls
- * @tty: tty for the ioctl
- * @cmd: command
- * @arg: ioctl argument
+ * tty_mode_ioctl - mode related ioctls
+ * @tty: tty for the ioctl
+ * @cmd: command
+ * @arg: ioctl argument
*
- * Perform non line discipline specific mode control ioctls. This
- * is designed to be called by line disciplines to ensure they provide
- * consistent mode setting.
+ * Perform non-line discipline specific mode control ioctls. This is designed
+ * to be called by line disciplines to ensure they provide consistent mode
+ * setting.
*/
-
int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
{
struct tty_struct *real_tty;
--
2.42.0
