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author | Julian Andres Klode <jak@jak-linux.org> | 2011-09-27 17:00:56 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-09-30 00:41:35 (GMT) |
commit | bdf034d98676d143cb88f7b999a71fff5775fcd4 (patch) | |
tree | 16cb97983cbf5d0095443c97b297977565feb825 /drivers/staging/nvec/nvec.c | |
parent | 1b9bf629ea42fdacd951b9190f86b028557bbe19 (diff) | |
download | linux-bdf034d98676d143cb88f7b999a71fff5775fcd4.tar.xz |
staging: nvec: Document public and private API
Add kernel-doc comments describing the functions
and structs we currently have.
Signed-off-by: Julian Andres Klode <jak@jak-linux.org>
Acked-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/staging/nvec/nvec.c')
-rw-r--r-- | drivers/staging/nvec/nvec.c | 109 |
1 files changed, 107 insertions, 2 deletions
diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c index dc3c0c6..057c888 100644 --- a/drivers/staging/nvec/nvec.c +++ b/drivers/staging/nvec/nvec.c @@ -71,6 +71,15 @@ static struct mfd_cell nvec_devices[] = { }, }; +/** + * nvec_register_notifier - Register a notifier with nvec + * @nvec: A &struct nvec_chip + * @nb: The notifier block to register + * + * Registers a notifier with @nvec. The notifier will be added to an atomic + * notifier chain that is called for all received messages except those that + * correspond to a request initiated by nvec_write_sync(). + */ int nvec_register_notifier(struct nvec_chip *nvec, struct notifier_block *nb, unsigned int events) { @@ -78,6 +87,12 @@ int nvec_register_notifier(struct nvec_chip *nvec, struct notifier_block *nb, } EXPORT_SYMBOL_GPL(nvec_register_notifier); +/** + * nvec_status_notifier - The final notifier + * + * Prints a message about control events not handled in the notifier + * chain. + */ static int nvec_status_notifier(struct notifier_block *nb, unsigned long event_type, void *data) { @@ -93,6 +108,14 @@ static int nvec_status_notifier(struct notifier_block *nb, return NOTIFY_OK; } +/** + * nvec_msg_alloc: + * @nvec: A &struct nvec_chip + * + * Allocate a single &struct nvec_msg object from the message pool of + * @nvec. The result shall be passed to nvec_msg_free() if no longer + * used. + */ static struct nvec_msg *nvec_msg_alloc(struct nvec_chip *nvec) { int i; @@ -109,6 +132,13 @@ static struct nvec_msg *nvec_msg_alloc(struct nvec_chip *nvec) return NULL; } +/** + * nvec_msg_free: + * @nvec: A &struct nvec_chip + * @msg: A message (must be allocated by nvec_msg_alloc() and belong to @nvec) + * + * Free the given message + */ static void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg) { if (msg != &nvec->tx_scratch) @@ -147,6 +177,13 @@ static size_t nvec_msg_size(struct nvec_msg *msg) return 0; } +/** + * nvec_gpio_set_value - Set the GPIO value + * @nvec: A &struct nvec_chip + * @value: The value to write (0 or 1) + * + * Like gpio_set_value(), but generating debugging information + */ static void nvec_gpio_set_value(struct nvec_chip *nvec, int value) { dev_dbg(nvec->dev, "GPIO changed from %u to %u\n", @@ -154,6 +191,18 @@ static void nvec_gpio_set_value(struct nvec_chip *nvec, int value) gpio_set_value(nvec->gpio, value); } +/** + * nvec_write_async - Asynchronously write a message to NVEC + * @nvec: An nvec_chip instance + * @data: The message data, starting with the request type + * @size: The size of @data + * + * Queue a single message to be transferred to the embedded controller + * and return immediately. + * + * Returns: 0 on success, a negative error code on failure. If a failure + * occured, the nvec driver may print an error. + */ int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data, short size) { @@ -178,6 +227,20 @@ int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data, } EXPORT_SYMBOL(nvec_write_async); +/** + * nvec_write_sync - Write a message to nvec and read the response + * @nvec: An &struct nvec_chip + * @data: The data to write + * @size: The size of @data + * + * This is similar to nvec_write_async(), but waits for the + * request to be answered before returning. This function + * uses a mutex and can thus not be called from e.g. + * interrupt handlers. + * + * Returns: A pointer to the response message on success, + * %NULL on failure. + */ struct nvec_msg *nvec_write_sync(struct nvec_chip *nvec, const unsigned char *data, short size) { @@ -209,7 +272,14 @@ struct nvec_msg *nvec_write_sync(struct nvec_chip *nvec, } EXPORT_SYMBOL(nvec_write_sync); -/* TX worker */ +/** + * nvec_request_master - Process outgoing messages + * @work: A &struct work_struct (the tx_worker member of &struct nvec_chip) + * + * Processes all outgoing requests by sending the request and awaiting the + * response, then continuing with the next request. Once a request has a + * matching response, it will be freed and removed from the list. + */ static void nvec_request_master(struct work_struct *work) { struct nvec_chip *nvec = container_of(work, struct nvec_chip, tx_work); @@ -241,6 +311,14 @@ static void nvec_request_master(struct work_struct *work) spin_unlock_irqrestore(&nvec->tx_lock, flags); } +/** + * parse_msg - Print some information and call the notifiers on an RX message + * @nvec: A &struct nvec_chip + * @msg: A message received by @nvec + * + * Paarse some pieces of the message and then call the chain of notifiers + * registered via nvec_register_notifier. + */ static int parse_msg(struct nvec_chip *nvec, struct nvec_msg *msg) { if ((msg->data[0] & 1 << 7) == 0 && msg->data[3]) { @@ -260,7 +338,13 @@ static int parse_msg(struct nvec_chip *nvec, struct nvec_msg *msg) return 0; } -/* RX worker */ +/** + * nvec_dispatch - Process messages received from the EC + * @work: A &struct work_struct (the tx_worker member of &struct nvec_chip) + * + * Process messages previously received from the EC and put into the RX + * queue of the &struct nvec_chip instance associated with @work. + */ static void nvec_dispatch(struct work_struct *work) { struct nvec_chip *nvec = container_of(work, struct nvec_chip, rx_work); @@ -288,6 +372,12 @@ static void nvec_dispatch(struct work_struct *work) spin_unlock_irqrestore(&nvec->rx_lock, flags); } +/** + * nvec_tx_completed - Complete the current transfer + * @nvec: A &struct nvec_chip + * + * This is called when we have received an END_TRANS on a TX transfer. + */ static void nvec_tx_completed(struct nvec_chip *nvec) { /* We got an END_TRANS, let's skip this, maybe there's an event */ @@ -300,6 +390,12 @@ static void nvec_tx_completed(struct nvec_chip *nvec) } } +/** + * nvec_rx_completed - Complete the current transfer + * @nvec: A &struct nvec_chip + * + * This is called when we have received an END_TRANS on a RX transfer. + */ static void nvec_rx_completed(struct nvec_chip *nvec) { if (nvec->rx->pos != nvec_msg_size(nvec->rx)) @@ -340,6 +436,11 @@ static void nvec_invalid_flags(struct nvec_chip *nvec, unsigned int status, /** * nvec_tx_set - Set the message to transfer (nvec->tx) + * @nvec: A &struct nvec_chip + * + * Gets the first entry from the tx_data list of @nvec and sets the + * tx member to it. If the tx_data list is empty, this uses the + * tx_scratch message to send a no operation message. */ static void nvec_tx_set(struct nvec_chip *nvec) { @@ -366,6 +467,10 @@ static void nvec_tx_set(struct nvec_chip *nvec) * nvec_interrupt - Interrupt handler * @irq: The IRQ * @dev: The nvec device + * + * Interrupt handler that fills our RX buffers and empties our TX + * buffers. This uses a finite state machine with ridiculous amounts + * of error checking, in order to be fairly reliable. */ static irqreturn_t nvec_interrupt(int irq, void *dev) { |