OMAP clockdomain/powerdomain: improve documentation

This patch only affects documentation; no functional changes are
included.

Clean up comments in the current clockdomain, powerdomain code and
header files.  This mostly involves conversion to kerneldoc format,
although some clarifications are also included.
Signed-off-by: Paul Walmsley <paul@pwsan.com>

arch/arm/mach-omap2/clockdomain.c

@@ -351,10 +351,10 @@ static void _init_sleepdep_usecount(struct clockdomain *clkdm)
  * @init_autodeps: optional pointer to an array of autodeps to register
  *
  * Set up internal state.  If a pointer to an array of clockdomains
- * was supplied, loop through the list of clockdomains, register all
- * that are available on the current platform. Similarly, if a pointer
- * to an array of clockdomain autodependencies was provided, register
- * those.  No return value.
+ * @clkdms was supplied, loop through the list of clockdomains,
+ * register all that are available on the current platform. Similarly,
+ * if a pointer to an array of clockdomain autodependencies
+ * @init_autodeps was provided, register those.  No return value.
  */
 void clkdm_init(struct clockdomain **clkdms,
 		struct clkdm_autodep *init_autodeps)
@@ -386,8 +386,8 @@ void clkdm_init(struct clockdomain **clkdms,
  * clkdm_lookup - look up a clockdomain by name, return a pointer
  * @name: name of clockdomain
  *
- * Find a registered clockdomain by its name.  Returns a pointer to the
- * struct clockdomain if found, or NULL otherwise.
+ * Find a registered clockdomain by its name @name.  Returns a pointer
+ * to the struct clockdomain if found, or NULL otherwise.
  */
 struct clockdomain *clkdm_lookup(const char *name)
 {
@@ -412,8 +412,8 @@ struct clockdomain *clkdm_lookup(const char *name)
  * clkdm_for_each - call function on each registered clockdomain
  * @fn: callback function *
  *
- * Call the supplied function for each registered clockdomain.
- * The callback function can return anything but 0 to bail
+ * Call the supplied function @fn for each registered clockdomain.
+ * The callback function @fn can return anything but 0 to bail
  * out early from the iterator.  The callback function is called with
  * the clkdm_mutex held, so no clockdomain structure manipulation
  * functions should be called from the callback, although hardware
@@ -446,7 +446,7 @@ int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user),
  * @clkdm: struct clockdomain *
  *
  * Return a pointer to the struct powerdomain that the specified clockdomain
- * 'clkdm' exists in, or returns NULL if clkdm argument is NULL.
+ * @clkdm exists in, or returns NULL if @clkdm is NULL.
  */
 struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm)
 {
@@ -759,10 +759,10 @@ int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm)
 
 /**
  * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode
- * @clk: struct clk * of a clockdomain
+ * @clkdm: struct clkdm * of a clockdomain
  *
- * Return the clockdomain's current state transition mode from the
- * corresponding domain OMAP2_CM_CLKSTCTRL register.	Returns -EINVAL if clk
+ * Return the clockdomain @clkdm current state transition mode from the
+ * corresponding domain CM_CLKSTCTRL register.	Returns -EINVAL if @clkdm
  * is NULL or the current mode upon success.
  */
 static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
@@ -784,7 +784,7 @@ static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
  * @clkdm: struct clockdomain *
  *
  * Instruct the CM to force a sleep transition on the specified
- * clockdomain 'clkdm'.  Returns -EINVAL if clk is NULL or if
+ * clockdomain @clkdm.  Returns -EINVAL if @clkdm is NULL or if
  * clockdomain does not support software-initiated sleep; 0 upon
  * success.
  */
@@ -828,7 +828,7 @@ int omap2_clkdm_sleep(struct clockdomain *clkdm)
  * @clkdm: struct clockdomain *
  *
  * Instruct the CM to force a wakeup transition on the specified
- * clockdomain 'clkdm'.  Returns -EINVAL if clkdm is NULL or if the
+ * clockdomain @clkdm.  Returns -EINVAL if @clkdm is NULL or if the
  * clockdomain does not support software-controlled wakeup; 0 upon
  * success.
  */
@@ -871,7 +871,7 @@ int omap2_clkdm_wakeup(struct clockdomain *clkdm)
  * omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm
  * @clkdm: struct clockdomain *
  *
- * Allow the hardware to automatically switch the clockdomain into
+ * Allow the hardware to automatically switch the clockdomain @clkdm into
  * active or idle states, as needed by downstream clocks.  If the
  * clockdomain has any downstream clocks enabled in the clock
  * framework, wkdep/sleepdep autodependencies are added; this is so
@@ -904,8 +904,8 @@ void omap2_clkdm_allow_idle(struct clockdomain *clkdm)
  * @clkdm: struct clockdomain *
  *
  * Prevent the hardware from automatically switching the clockdomain
- * into inactive or idle states.  If the clockdomain has downstream
- * clocks enabled in the clock framework, wkdep/sleepdep
+ * @clkdm into inactive or idle states.  If the clockdomain has
+ * downstream clocks enabled in the clock framework, wkdep/sleepdep
  * autodependencies are removed.  No return value.
  */
 void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
@@ -936,14 +936,14 @@ void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
  * @clkdm: struct clockdomain *
  * @clk: struct clk * of the enabled downstream clock
  *
- * Increment the usecount of this clockdomain 'clkdm' and ensure that
- * it is awake.  Intended to be called by clk_enable() code.  If the
- * clockdomain is in software-supervised idle mode, force the
- * clockdomain to wake.  If the clockdomain is in hardware-supervised
- * idle mode, add clkdm-pwrdm autodependencies, to ensure that devices
- * in the clockdomain can be read from/written to by on-chip processors.
- * Returns -EINVAL if passed null pointers; returns 0 upon success or
- * if the clockdomain is in hwsup idle mode.
+ * Increment the usecount of the clockdomain @clkdm and ensure that it
+ * is awake before @clk is enabled.  Intended to be called by
+ * clk_enable() code.  If the clockdomain is in software-supervised
+ * idle mode, force the clockdomain to wake.  If the clockdomain is in
+ * hardware-supervised idle mode, add clkdm-pwrdm autodependencies, to
+ * ensure that devices in the clockdomain can be read from/written to
+ * by on-chip processors.  Returns -EINVAL if passed null pointers;
+ * returns 0 upon success or if the clockdomain is in hwsup idle mode.
  */
 int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk)
 {
@@ -988,13 +988,14 @@ int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk)
  * @clkdm: struct clockdomain *
  * @clk: struct clk * of the disabled downstream clock
  *
- * Decrement the usecount of this clockdomain 'clkdm'. Intended to be
- * called by clk_disable() code.  If the usecount goes to 0, put the
- * clockdomain to sleep (software-supervised mode) or remove the
- * clkdm-pwrdm autodependencies (hardware-supervised mode).  Returns
- * -EINVAL if passed null pointers; -ERANGE if the clkdm usecount
- * underflows and debugging is enabled; or returns 0 upon success or
- * if the clockdomain is in hwsup idle mode.
+ * Decrement the usecount of this clockdomain @clkdm when @clk is
+ * disabled.  Intended to be called by clk_disable() code.  If the
+ * clockdomain usecount goes to 0, put the clockdomain to sleep
+ * (software-supervised mode) or remove the clkdm autodependencies
+ * (hardware-supervised mode).  Returns -EINVAL if passed null
+ * pointers; -ERANGE if the @clkdm usecount underflows and debugging
+ * is enabled; or returns 0 upon success or if the clockdomain is in
+ * hwsup idle mode.
  */
 int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk)
 {

arch/arm/plat-omap/include/plat/clockdomain.h

@@ -40,86 +40,77 @@
 #define OMAP34XX_CLKSTCTRL_FORCE_WAKEUP		0x2
 #define OMAP34XX_CLKSTCTRL_ENABLE_AUTO		0x3
 
-/*
- * struct clkdm_autodep - a clockdomain that should have wkdeps
- * and sleepdeps added when a clockdomain should stay active in hwsup mode;
- * and conversely, removed when the clockdomain should be allowed to go
- * inactive in hwsup mode.
+/**
+ * struct clkdm_autodep - clkdm deps to add when entering/exiting hwsup mode
+ * @clkdm: clockdomain to add wkdep+sleepdep on - set name member only
+ * @omap_chip: OMAP chip types that this autodep is valid on
+ *
+ * A clockdomain that should have wkdeps and sleepdeps added when a
+ * clockdomain should stay active in hwsup mode; and conversely,
+ * removed when the clockdomain should be allowed to go inactive in
+ * hwsup mode.
+ *
+ * Autodeps are deprecated and should be removed after
+ * omap_hwmod-based fine-grained module idle control is added.
  */
 struct clkdm_autodep {
-
 	union {
-		/* Name of the clockdomain to add a wkdep/sleepdep on */
 		const char *name;
-
-		/* Clockdomain pointer (looked up at clkdm_init() time) */
 		struct clockdomain *ptr;
 	} clkdm;
-
-	/* OMAP chip types that this clockdomain dep is valid on */
 	const struct omap_chip_id omap_chip;
-
 };
 
-/* Encodes dependencies between clockdomains - statically defined */
+/**
+ * struct clkdm_dep - encode dependencies between clockdomains
+ * @clkdm_name: clockdomain name
+ * @clkdm: pointer to the struct clockdomain of @clkdm_name
+ * @omap_chip: OMAP chip types that this dependency is valid on
+ * @wkdep_usecount: Number of wakeup dependencies causing this clkdm to wake
+ * @sleepdep_usecount: Number of sleep deps that could prevent clkdm from idle
+ *
+ * Statically defined.  @clkdm is resolved from @clkdm_name at runtime and
+ * should not be pre-initialized.
+ *
+ * XXX Should also include hardware (fixed) dependencies.
+ */
 struct clkdm_dep {
-
-	/* Clockdomain name */
 	const char *clkdm_name;
-
-	/* Clockdomain pointer - resolved by the clockdomain code */
 	struct clockdomain *clkdm;
-
-	/* Number of wakeup dependencies causing this clkdm to wake  */
 	atomic_t wkdep_usecount;
-
-	/* Number of sleep dependencies that could prevent clkdm from idle */
 	atomic_t sleepdep_usecount;
-
-	/* Flags to mark OMAP chip restrictions, etc. */
 	const struct omap_chip_id omap_chip;
-
 };
 
+/**
+ * struct clockdomain - OMAP clockdomain
+ * @name: clockdomain name
+ * @pwrdm: powerdomain containing this clockdomain
+ * @clktrctrl_reg: CLKSTCTRL reg for the given clock domain
+ * @clktrctrl_mask: CLKTRCTRL/AUTOSTATE field mask in CM_CLKSTCTRL reg
+ * @flags: Clockdomain capability flags
+ * @dep_bit: Bit shift of this clockdomain's PM_WKDEP/CM_SLEEPDEP bit
+ * @wkdep_srcs: Clockdomains that can be told to wake this powerdomain up
+ * @sleepdep_srcs: Clockdomains that can be told to keep this clkdm from inact
+ * @omap_chip: OMAP chip types that this clockdomain is valid on
+ * @usecount: Usecount tracking
+ * @node: list_head to link all clockdomains together
+ */
 struct clockdomain {
-
-	/* Clockdomain name */
 	const char *name;
-
 	union {
-		/* Powerdomain enclosing this clockdomain */
 		const char *name;
-
-		/* Powerdomain pointer assigned at clkdm_register() */
 		struct powerdomain *ptr;
 	} pwrdm;
-
-	/* CLKSTCTRL reg for the given clock domain*/
 	void __iomem *clkstctrl_reg;
-
-	/* CLKTRCTRL/AUTOSTATE field mask in CM_CLKSTCTRL reg */
 	const u16 clktrctrl_mask;
-
-	/* Clockdomain capability flags */
 	const u8 flags;
-
-	/* Bit shift of this clockdomain's PM_WKDEP/CM_SLEEPDEP bit */
 	const u8 dep_bit;
-
-	/* Clockdomains that can be told to wake this powerdomain up */
 	struct clkdm_dep *wkdep_srcs;
-
-	/* Clockdomains that can be told to keep this clkdm from inactivity */
 	struct clkdm_dep *sleepdep_srcs;
-
-	/* OMAP chip types that this clockdomain is valid on */
 	const struct omap_chip_id omap_chip;
-
-	/* Usecount tracking */
 	atomic_t usecount;
-
 	struct list_head node;
-
 };
 
 void clkdm_init(struct clockdomain **clkdms, struct clkdm_autodep *autodeps);

arch/arm/plat-omap/include/plat/powerdomain.h

@@ -68,40 +68,36 @@
 struct clockdomain;
 struct powerdomain;
 
+/**
+ * struct powerdomain - OMAP powerdomain
+ * @name: Powerdomain name
+ * @omap_chip: represents the OMAP chip types containing this pwrdm
+ * @prcm_offs: the address offset from CM_BASE/PRM_BASE
+ * @pwrsts: Possible powerdomain power states
+ * @pwrsts_logic_ret: Possible logic power states when pwrdm in RETENTION
+ * @flags: Powerdomain flags
+ * @banks: Number of software-controllable memory banks in this powerdomain
+ * @pwrsts_mem_ret: Possible memory bank pwrstates when pwrdm in RETENTION
+ * @pwrsts_mem_on: Possible memory bank pwrstates when pwrdm in ON
+ * @pwrdm_clkdms: Clockdomains in this powerdomain
+ * @node: list_head linking all powerdomains
+ * @state:
+ * @state_counter:
+ * @timer:
+ * @state_timer:
+ */
 struct powerdomain {
-
-	/* Powerdomain name */
 	const char *name;
-
-	/* Used to represent the OMAP chip types containing this pwrdm */
 	const struct omap_chip_id omap_chip;
-
-	/* the address offset from CM_BASE/PRM_BASE */
 	const s16 prcm_offs;
-
-	/* Possible powerdomain power states */
 	const u8 pwrsts;
-
-	/* Possible logic power states when pwrdm in RETENTION */
 	const u8 pwrsts_logic_ret;
-
-	/* Powerdomain flags */
 	const u8 flags;
-
-	/* Number of software-controllable memory banks in this powerdomain */
 	const u8 banks;
-
-	/* Possible memory bank pwrstates when pwrdm in RETENTION */
 	const u8 pwrsts_mem_ret[PWRDM_MAX_MEM_BANKS];
-
-	/* Possible memory bank pwrstates when pwrdm is ON */
 	const u8 pwrsts_mem_on[PWRDM_MAX_MEM_BANKS];
-
-	/* Clockdomains in this powerdomain */
 	struct clockdomain *pwrdm_clkdms[PWRDM_MAX_CLKDMS];
-
 	struct list_head node;
-
 	int state;
 	unsigned state_counter[PWRDM_MAX_PWRSTS];