kerneldoc: Annotate drivers/serial/serial.c

Add kerneldoc annotations into serial core. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Tom Rini <trini@ti.com>

kerneldoc: Annotate drivers/serial/serial.c
Add kerneldoc annotations into serial core. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Tom Rini <trini@ti.com>
Marek Vasut · Tom Rini
1 parent dee1941604
Showing 1 changed file with 165 additions and 0 deletions Side-by-side Diff
drivers/serial/serial.c
@@ -33,10 +33,28 @@
 static struct serial_device *serial_devices;
 static struct serial_device *serial_current;
  
+/**
+ * serial_null() - Void registration routine of a serial driver
+ *
+ * This routine implements a void registration routine of a serial
+ * driver. The registration routine of a particular driver is aliased
+ * to this empty function in case the driver is not compiled into
+ * U-Boot.
+ */
 static void serial_null(void)
 {
 }
  
+/**
+ * serial_initfunc() - Forward declare of driver registration routine
+ * @name:	Name of the real driver registration routine.
+ *
+ * This macro expands onto forward declaration of a driver registration
+ * routine, which is then used below in serial_initialize() function.
+ * The declaration is made weak and aliases to serial_null() so in case
+ * the driver is not compiled in, the function is still declared and can
+ * be used, but aliases to serial_null() and thus is optimized away.
+ */
 #define serial_initfunc(name)					\
 	void name(void)						\
 		__attribute__((weak, alias("serial_null")));
@@ -95,6 +113,16 @@
 serial_initfunc(sa1100_serial_initialize);
 serial_initfunc(sh_serial_initialize);
  
+/**
+ * serial_register() - Register serial driver with serial driver core
+ * @dev:	Pointer to the serial driver structure
+ *
+ * This function registers the serial driver supplied via @dev with
+ * serial driver core, thus making U-Boot aware of it and making it
+ * available for U-Boot to use. On platforms that still require manual
+ * relocation of constant variables, relocation of the supplied structure
+ * is performed.
+ */
 void serial_register(struct serial_device *dev)
 {
 #ifdef CONFIG_NEEDS_MANUAL_RELOC
@@ -118,6 +146,15 @@
 	serial_devices = dev;
 }
  
+/**
+ * serial_initialize() - Register all compiled-in serial port drivers
+ *
+ * This function registers all serial port drivers that are compiled
+ * into the U-Boot binary with the serial core, thus making them
+ * available to U-Boot to use. Lastly, this function assigns a default
+ * serial port to the serial core. That serial port is then used as a
+ * default output.
+ */
 void serial_initialize(void)
 {
 	mpc8xx_serial_initialize();
@@ -177,6 +214,13 @@
 	serial_assign(default_serial_console()->name);
 }
  
+/**
+ * serial_stdio_init() - Register serial ports with STDIO core
+ *
+ * This function generates a proxy driver for each serial port driver.
+ * These proxy drivers then register with the STDIO core, making the
+ * serial drivers available as STDIO devices.
+ */
 void serial_stdio_init(void)
 {
 	struct stdio_dev dev;
@@ -201,6 +245,18 @@
 	}
 }
  
+/**
+ * serial_assign() - Select the serial output device by name
+ * @name:	Name of the serial driver to be used as default output
+ *
+ * This function configures the serial output multiplexing by
+ * selecting which serial device will be used as default. In case
+ * the STDIO "serial" device is selected as stdin/stdout/stderr,
+ * the serial device previously configured by this function will be
+ * used for the particular operation.
+ *
+ * Returns 0 on success, negative on error.
+ */
 int serial_assign(const char *name)
 {
 	struct serial_device *s;
@@ -215,6 +271,12 @@
 	return -EINVAL;
 }
  
+/**
+ * serial_reinit_all() - Reinitialize all compiled-in serial ports
+ *
+ * This function reinitializes all serial ports that are compiled
+ * into U-Boot by calling their serial_start() functions.
+ */
 void serial_reinit_all(void)
 {
 	struct serial_device *s;
@@ -223,6 +285,21 @@
 		s->start();
 }
  
+/**
+ * get_current() - Return pointer to currently selected serial port
+ *
+ * This function returns a pointer to currently selected serial port.
+ * The currently selected serial port is altered by serial_assign()
+ * function.
+ *
+ * In case this function is called before relocation or before any serial
+ * port is configured, this function calls default_serial_console() to
+ * determine the serial port. Otherwise, the configured serial port is
+ * returned.
+ *
+ * Returns pointer to the currently selected serial port on success,
+ * NULL on error.
+ */
 static struct serial_device *get_current(void)
 {
 	struct serial_device *dev;
  
  
  
  
  
  
@@ -247,36 +324,113 @@
 	return dev;
 }
  
+/**
+ * serial_init() - Initialize currently selected serial port
+ *
+ * This function initializes the currently selected serial port. This
+ * usually involves setting up the registers of that particular port,
+ * enabling clock and such. This function uses the get_current() call
+ * to determine which port is selected.
+ *
+ * Returns 0 on success, negative on error.
+ */
 int serial_init(void)
 {
 	return get_current()->start();
 }
  
+/**
+ * serial_setbrg() - Configure baud-rate of currently selected serial port
+ *
+ * This function configures the baud-rate of the currently selected
+ * serial port. The baud-rate is retrieved from global data within
+ * the serial port driver. This function uses the get_current() call
+ * to determine which port is selected.
+ *
+ * Returns 0 on success, negative on error.
+ */
 void serial_setbrg(void)
 {
 	get_current()->setbrg();
 }
  
+/**
+ * serial_getc() - Read character from currently selected serial port
+ *
+ * This function retrieves a character from currently selected serial
+ * port. In case there is no character waiting on the serial port,
+ * this function will block and wait for the character to appear. This
+ * function uses the get_current() call to determine which port is
+ * selected.
+ *
+ * Returns the character on success, negative on error.
+ */
 int serial_getc(void)
 {
 	return get_current()->getc();
 }
  
+/**
+ * serial_tstc() - Test if data is available on currently selected serial port
+ *
+ * This function tests if one or more characters are available on
+ * currently selected serial port. This function never blocks. This
+ * function uses the get_current() call to determine which port is
+ * selected.
+ *
+ * Returns positive if character is available, zero otherwise.
+ */
 int serial_tstc(void)
 {
 	return get_current()->tstc();
 }
  
+/**
+ * serial_putc() - Output character via currently selected serial port
+ * @c:	Single character to be output from the serial port.
+ *
+ * This function outputs a character via currently selected serial
+ * port. This character is passed to the serial port driver responsible
+ * for controlling the hardware. The hardware may still be in process
+ * of transmitting another character, therefore this function may block
+ * for a short amount of time. This function uses the get_current()
+ * call to determine which port is selected.
+ */
 void serial_putc(const char c)
 {
 	get_current()->putc(c);
 }
  
+/**
+ * serial_puts() - Output string via currently selected serial port
+ * @s:	Zero-terminated string to be output from the serial port.
+ *
+ * This function outputs a zero-terminated string via currently
+ * selected serial port. This function behaves as an accelerator
+ * in case the hardware can queue multiple characters for transfer.
+ * The whole string that is to be output is available to the function
+ * implementing the hardware manipulation. Transmitting the whole
+ * string may take some time, thus this function may block for some
+ * amount of time. This function uses the get_current() call to
+ * determine which port is selected.
+ */
 void serial_puts(const char *s)
 {
 	get_current()->puts(s);
 }
  
+/**
+ * default_serial_puts() - Output string by calling serial_putc() in loop
+ * @s:	Zero-terminated string to be output from the serial port.
+ *
+ * This function outputs a zero-terminated string by calling serial_putc()
+ * in a loop. Most drivers do not support queueing more than one byte for
+ * transfer, thus this function precisely implements their serial_puts().
+ *
+ * To optimize the number of get_current() calls, this function only
+ * calls get_current() once and then directly accesses the putc() call
+ * of the &struct serial_device .
+ */
 void default_serial_puts(const char *s)
 {
 	struct serial_device *dev = get_current();
@@ -287,6 +441,17 @@
 #if CONFIG_POST & CONFIG_SYS_POST_UART
 static const int bauds[] = CONFIG_SYS_BAUDRATE_TABLE;
  
+/**
+ * uart_post_test() - Test the currently selected serial port using POST
+ * @flags:	POST framework flags
+ *
+ * Do a loopback test of the currently selected serial port. This
+ * function is only useful in the context of the POST testing framwork.
+ * The serial port is firstly configured into loopback mode and then
+ * characters are sent through it.
+ *
+ * Returns 0 on success, value otherwise.
+ */
 /* Mark weak until post/cpu/.../uart.c migrate over */
 __weak
 int uart_post_test(int flags)
...	...	@@ -33,10 +33,28 @@
33	33	static struct serial_device *serial_devices;
34	34	static struct serial_device *serial_current;
35	35
	36	+/**
	37	+ * serial_null() - Void registration routine of a serial driver
	38	+ *
	39	+ * This routine implements a void registration routine of a serial
	40	+ * driver. The registration routine of a particular driver is aliased
	41	+ * to this empty function in case the driver is not compiled into
	42	+ * U-Boot.
	43	+ */
36	44	static void serial_null(void)
37	45	{
38	46	}
39	47
	48	+/**
	49	+ * serial_initfunc() - Forward declare of driver registration routine
	50	+ * @name: Name of the real driver registration routine.
	51	+ *
	52	+ * This macro expands onto forward declaration of a driver registration
	53	+ * routine, which is then used below in serial_initialize() function.
	54	+ * The declaration is made weak and aliases to serial_null() so in case
	55	+ * the driver is not compiled in, the function is still declared and can
	56	+ * be used, but aliases to serial_null() and thus is optimized away.
	57	+ */
40	58	#define serial_initfunc(name) \
41	59	void name(void) \
42	60	__attribute__((weak, alias("serial_null")));
...	...	@@ -95,6 +113,16 @@
95	113	serial_initfunc(sa1100_serial_initialize);
96	114	serial_initfunc(sh_serial_initialize);
97	115
	116	+/**
	117	+ * serial_register() - Register serial driver with serial driver core
	118	+ * @dev: Pointer to the serial driver structure
	119	+ *
	120	+ * This function registers the serial driver supplied via @dev with
	121	+ * serial driver core, thus making U-Boot aware of it and making it
	122	+ * available for U-Boot to use. On platforms that still require manual
	123	+ * relocation of constant variables, relocation of the supplied structure
	124	+ * is performed.
	125	+ */
98	126	void serial_register(struct serial_device *dev)
99	127	{
100	128	#ifdef CONFIG_NEEDS_MANUAL_RELOC
...	...	@@ -118,6 +146,15 @@
118	146	serial_devices = dev;
119	147	}
120	148
	149	+/**
	150	+ * serial_initialize() - Register all compiled-in serial port drivers
	151	+ *
	152	+ * This function registers all serial port drivers that are compiled
	153	+ * into the U-Boot binary with the serial core, thus making them
	154	+ * available to U-Boot to use. Lastly, this function assigns a default
	155	+ * serial port to the serial core. That serial port is then used as a
	156	+ * default output.
	157	+ */
121	158	void serial_initialize(void)
122	159	{
123	160	mpc8xx_serial_initialize();
...	...	@@ -177,6 +214,13 @@
177	214	serial_assign(default_serial_console()->name);
178	215	}
179	216
	217	+/**
	218	+ * serial_stdio_init() - Register serial ports with STDIO core
	219	+ *
	220	+ * This function generates a proxy driver for each serial port driver.
	221	+ * These proxy drivers then register with the STDIO core, making the
	222	+ * serial drivers available as STDIO devices.
	223	+ */
180	224	void serial_stdio_init(void)
181	225	{
182	226	struct stdio_dev dev;
...	...	@@ -201,6 +245,18 @@
201	245	}
202	246	}
203	247
	248	+/**
	249	+ * serial_assign() - Select the serial output device by name
	250	+ * @name: Name of the serial driver to be used as default output
	251	+ *
	252	+ * This function configures the serial output multiplexing by
	253	+ * selecting which serial device will be used as default. In case
	254	+ * the STDIO "serial" device is selected as stdin/stdout/stderr,
	255	+ * the serial device previously configured by this function will be
	256	+ * used for the particular operation.
	257	+ *
	258	+ * Returns 0 on success, negative on error.
	259	+ */
204	260	int serial_assign(const char *name)
205	261	{
206	262	struct serial_device *s;
...	...	@@ -215,6 +271,12 @@
215	271	return -EINVAL;
216	272	}
217	273
	274	+/**
	275	+ * serial_reinit_all() - Reinitialize all compiled-in serial ports
	276	+ *
	277	+ * This function reinitializes all serial ports that are compiled
	278	+ * into U-Boot by calling their serial_start() functions.
	279	+ */
218	280	void serial_reinit_all(void)
219	281	{
220	282	struct serial_device *s;
...	...	@@ -223,6 +285,21 @@
223	285	s->start();
224	286	}
225	287
	288	+/**
	289	+ * get_current() - Return pointer to currently selected serial port
	290	+ *
	291	+ * This function returns a pointer to currently selected serial port.
	292	+ * The currently selected serial port is altered by serial_assign()
	293	+ * function.
	294	+ *
	295	+ * In case this function is called before relocation or before any serial
	296	+ * port is configured, this function calls default_serial_console() to
	297	+ * determine the serial port. Otherwise, the configured serial port is
	298	+ * returned.
	299	+ *
	300	+ * Returns pointer to the currently selected serial port on success,
	301	+ * NULL on error.
	302	+ */
226	303	static struct serial_device *get_current(void)
227	304	{
228	305	struct serial_device *dev;
229	306
230	307
231	308
232	309
233	310
234	311
...	...	@@ -247,36 +324,113 @@
247	324	return dev;
248	325	}
249	326
	327	+/**
	328	+ * serial_init() - Initialize currently selected serial port
	329	+ *
	330	+ * This function initializes the currently selected serial port. This
	331	+ * usually involves setting up the registers of that particular port,
	332	+ * enabling clock and such. This function uses the get_current() call
	333	+ * to determine which port is selected.
	334	+ *
	335	+ * Returns 0 on success, negative on error.
	336	+ */
250	337	int serial_init(void)
251	338	{
252	339	return get_current()->start();
253	340	}
254	341
	342	+/**
	343	+ * serial_setbrg() - Configure baud-rate of currently selected serial port
	344	+ *
	345	+ * This function configures the baud-rate of the currently selected
	346	+ * serial port. The baud-rate is retrieved from global data within
	347	+ * the serial port driver. This function uses the get_current() call
	348	+ * to determine which port is selected.
	349	+ *
	350	+ * Returns 0 on success, negative on error.
	351	+ */
255	352	void serial_setbrg(void)
256	353	{
257	354	get_current()->setbrg();
258	355	}
259	356
	357	+/**
	358	+ * serial_getc() - Read character from currently selected serial port
	359	+ *
	360	+ * This function retrieves a character from currently selected serial
	361	+ * port. In case there is no character waiting on the serial port,
	362	+ * this function will block and wait for the character to appear. This
	363	+ * function uses the get_current() call to determine which port is
	364	+ * selected.
	365	+ *
	366	+ * Returns the character on success, negative on error.
	367	+ */
260	368	int serial_getc(void)
261	369	{
262	370	return get_current()->getc();
263	371	}
264	372
	373	+/**
	374	+ * serial_tstc() - Test if data is available on currently selected serial port
	375	+ *
	376	+ * This function tests if one or more characters are available on
	377	+ * currently selected serial port. This function never blocks. This
	378	+ * function uses the get_current() call to determine which port is
	379	+ * selected.
	380	+ *
	381	+ * Returns positive if character is available, zero otherwise.
	382	+ */
265	383	int serial_tstc(void)
266	384	{
267	385	return get_current()->tstc();
268	386	}
269	387
	388	+/**
	389	+ * serial_putc() - Output character via currently selected serial port
	390	+ * @c: Single character to be output from the serial port.
	391	+ *
	392	+ * This function outputs a character via currently selected serial
	393	+ * port. This character is passed to the serial port driver responsible
	394	+ * for controlling the hardware. The hardware may still be in process
	395	+ * of transmitting another character, therefore this function may block
	396	+ * for a short amount of time. This function uses the get_current()
	397	+ * call to determine which port is selected.
	398	+ */
270	399	void serial_putc(const char c)
271	400	{
272	401	get_current()->putc(c);
273	402	}
274	403
	404	+/**
	405	+ * serial_puts() - Output string via currently selected serial port
	406	+ * @s: Zero-terminated string to be output from the serial port.
	407	+ *
	408	+ * This function outputs a zero-terminated string via currently
	409	+ * selected serial port. This function behaves as an accelerator
	410	+ * in case the hardware can queue multiple characters for transfer.
	411	+ * The whole string that is to be output is available to the function
	412	+ * implementing the hardware manipulation. Transmitting the whole
	413	+ * string may take some time, thus this function may block for some
	414	+ * amount of time. This function uses the get_current() call to
	415	+ * determine which port is selected.
	416	+ */
275	417	void serial_puts(const char *s)
276	418	{
277	419	get_current()->puts(s);
278	420	}
279	421
	422	+/**
	423	+ * default_serial_puts() - Output string by calling serial_putc() in loop
	424	+ * @s: Zero-terminated string to be output from the serial port.
	425	+ *
	426	+ * This function outputs a zero-terminated string by calling serial_putc()
	427	+ * in a loop. Most drivers do not support queueing more than one byte for
	428	+ * transfer, thus this function precisely implements their serial_puts().
	429	+ *
	430	+ * To optimize the number of get_current() calls, this function only
	431	+ * calls get_current() once and then directly accesses the putc() call
	432	+ * of the &struct serial_device .
	433	+ */
280	434	void default_serial_puts(const char *s)
281	435	{
282	436	struct serial_device *dev = get_current();
...	...	@@ -287,6 +441,17 @@
287	441	#if CONFIG_POST & CONFIG_SYS_POST_UART
288	442	static const int bauds[] = CONFIG_SYS_BAUDRATE_TABLE;
289	443
	444	+/**
	445	+ * uart_post_test() - Test the currently selected serial port using POST
	446	+ * @flags: POST framework flags
	447	+ *
	448	+ * Do a loopback test of the currently selected serial port. This
	449	+ * function is only useful in the context of the POST testing framwork.
	450	+ * The serial port is firstly configured into loopback mode and then
	451	+ * characters are sent through it.
	452	+ *
	453	+ * Returns 0 on success, value otherwise.
	454	+ */
290	455	/* Mark weak until post/cpu/.../uart.c migrate over */
291	456	__weak
292	457	int uart_post_test(int flags)