From patchwork Sat Jul 11 14:12:14 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Sakamoto X-Patchwork-Id: 6770391 Return-Path: X-Original-To: patchwork-alsa-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id BBBB3C05AC for ; Sat, 11 Jul 2015 14:13:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8FE632066A for ; Sat, 11 Jul 2015 14:13:58 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.kernel.org (Postfix) with ESMTP id 2CB602066C for ; Sat, 11 Jul 2015 14:13:57 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id 381802651ED; Sat, 11 Jul 2015 16:13:55 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,NO_DNS_FOR_FROM, UNPARSEABLE_RELAY autolearn=no version=3.3.1 Received: from alsa0.perex.cz (localhost [IPv6:::1]) by alsa0.perex.cz (Postfix) with ESMTP id 54755260558; Sat, 11 Jul 2015 16:13:12 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 107932605DC; Sat, 11 Jul 2015 16:13:10 +0200 (CEST) Received: from smtp301.phy.lolipop.jp (smtp301.phy.lolipop.jp [210.157.22.84]) by alsa0.perex.cz (Postfix) with ESMTP id 85443260558 for ; Sat, 11 Jul 2015 16:13:02 +0200 (CEST) Received: from smtp301.phy.lolipop.lan (HELO smtp301.phy.lolipop.jp) (172.17.1.84) (smtp-auth username m12129643-o-takashi, mechanism plain) by smtp301.phy.lolipop.jp (qpsmtpd/0.82) with ESMTPA; Sat, 11 Jul 2015 23:12:59 +0900 Received: from 127.0.0.1 (127.0.0.1) by smtp301.phy.lolipop.jp (LOLIPOP-Fsecure); Sat, 11 Jul 2015 23:12:49 +0900 (JST) X-Virus-Status: clean(LOLIPOP-Fsecure) From: Takashi Sakamoto To: clemens@ladisch.de Date: Sat, 11 Jul 2015 23:12:14 +0900 Message-Id: <1436623968-10780-4-git-send-email-o-takashi@sakamocchi.jp> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436623968-10780-1-git-send-email-o-takashi@sakamocchi.jp> References: <1436623968-10780-1-git-send-email-o-takashi@sakamocchi.jp> Cc: alsa-devel@alsa-project.org, ffado-devel@lists.sf.net Subject: [alsa-devel] [RFC][PATCH 03/37] ALSA: firewire-lib: add helper functions for asynchronous MIDI port X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP Some devices receive MIDI messages via IEEE 1394 asynchronous transactions with fixed length of payload data. It's nice for firewire-lib module to have common helper functions. This commit implements this idea. Each driver adds 'struct snd_fw_async_midi_port' in its data structure. In probing, it should call snd_fw_async_midi_port_init() to initialize the structure with some parameters such as target address, the length of data for a transaction and a pointer for callback function to fill the data buffer. When 'struct snd_rawmidi_ops.trigger()' callback, it should call 'snd_fw_async_midi_port_run()' to start transactions. Each driver should ensure that the lifetime of MIDI substream continues till calling 'snd_fw_async_midi_port_finish()'. These helper functions support retries to transferring MIDI messages when transmission errors occur. Therefore, these helper functions expect each driver to use 'snd_rawmidi_transmit_peek()'. When transmissions are successful, these helper functions call 'snd_rawmidi_transmit_ack()' to consume MIDI bytes in the buffer. Signed-off-by: Takashi Sakamoto --- sound/firewire/lib.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++ sound/firewire/lib.h | 46 +++++++++++++++++++++++++ 2 files changed, 141 insertions(+) diff --git a/sound/firewire/lib.c b/sound/firewire/lib.c index 7409edb..f5b5526 100644 --- a/sound/firewire/lib.c +++ b/sound/firewire/lib.c @@ -9,6 +9,7 @@ #include #include #include +#include #include "lib.h" #define ERROR_RETRY_DELAY_MS 20 @@ -66,6 +67,100 @@ int snd_fw_transaction(struct fw_unit *unit, int tcode, } EXPORT_SYMBOL(snd_fw_transaction); +static void async_midi_port_callback(struct fw_card *card, int rcode, + void *data, size_t length, + void *callback_data) +{ + struct snd_fw_async_midi_port *port = callback_data; + struct snd_rawmidi_substream *substream = ACCESS_ONCE(port->substream); + + if (rcode == RCODE_COMPLETE && substream != NULL) + snd_rawmidi_transmit_ack(substream, port->consume_bytes); +} + +static void midi_port_tasklet(unsigned long data) +{ + struct snd_fw_async_midi_port *port = + (struct snd_fw_async_midi_port *)data; + struct snd_rawmidi_substream *substream = ACCESS_ONCE(port->substream); + int generation; + int type; + + /* Nothing to do. */ + if (substream == NULL || snd_rawmidi_transmit_empty(substream)) + return; + + /* + * Fill the buffer. The callee must use snd_rawmidi_transmit_peek(). + * Later, snd_rawmidi_transmit_ack() may be called. + */ + memset(port->buf, 0, port->len); + port->consume_bytes = port->packetize(substream, port->buf); + if (port->consume_bytes <= 0) { + /* Do it in next chance, immediately. */ + if (port->consume_bytes == 0) + tasklet_schedule(&port->tasklet); + return; + } + + /* Calculate type of transaction. */ + if (port->len == 4) + type = TCODE_WRITE_QUADLET_REQUEST; + else + type = TCODE_WRITE_BLOCK_REQUEST; + + /* Start this transaction. */ + generation = port->parent->generation; + smp_rmb(); /* node_id vs. generation */ + fw_send_request(port->parent->card, &port->transaction, type, + port->parent->node_id, generation, + port->parent->max_speed, port->addr, + port->buf, port->len, async_midi_port_callback, + port); +} + +/** + * snd_fw_async_midi_port_init - initialize asynchronous MIDI port structure + * @port: the asynchronous MIDI port to initialize + * @unit: the target of the asynchronous transaction + * @addr: the address to which transactions are transferred + * @len: the length of transaction + * @packetize: the callback function to fill given buffer, and returns the + * number of consumed bytes for MIDI message. + * + */ +int snd_fw_async_midi_port_init(struct snd_fw_async_midi_port *port, + struct fw_unit *unit, __u64 addr, unsigned int len, + int (*packetize)(struct snd_rawmidi_substream *substream, + __u8 *buf)) +{ + port->len = DIV_ROUND_UP(len, 4) * 4; + port->buf = kzalloc(port->len, GFP_KERNEL); + if (port->buf == NULL) + return -ENOMEM; + + port->parent = fw_parent_device(unit); + port->addr = addr; + port->packetize = packetize; + + tasklet_init(&port->tasklet, midi_port_tasklet, (unsigned long)port); + + return 0; +} +EXPORT_SYMBOL(snd_fw_async_midi_port_init); + +/** + * snd_fw_async_midi_port_destroy - free asynchronous MIDI port structure + * @port: the asynchronous MIDI port structure + */ +void snd_fw_async_midi_port_destroy(struct snd_fw_async_midi_port *port) +{ + snd_fw_async_midi_port_finish(port); + tasklet_kill(&port->tasklet); + kfree(port->buf); +} +EXPORT_SYMBOL(snd_fw_async_midi_port_destroy); + MODULE_DESCRIPTION("FireWire audio helper functions"); MODULE_AUTHOR("Clemens Ladisch "); MODULE_LICENSE("GPL v2"); diff --git a/sound/firewire/lib.h b/sound/firewire/lib.h index 02cfabc..c662bf9 100644 --- a/sound/firewire/lib.h +++ b/sound/firewire/lib.h @@ -3,6 +3,8 @@ #include #include +#include +#include struct fw_unit; @@ -20,4 +22,48 @@ static inline bool rcode_is_permanent_error(int rcode) return rcode == RCODE_TYPE_ERROR || rcode == RCODE_ADDRESS_ERROR; } +struct snd_fw_async_midi_port { + struct fw_device *parent; + struct tasklet_struct tasklet; + + __u64 addr; + struct fw_transaction transaction; + + __u8 *buf; + unsigned int len; + + struct snd_rawmidi_substream *substream; + int (*packetize)(struct snd_rawmidi_substream *substream, __u8 *buf); + unsigned int consume_bytes; +}; + +int snd_fw_async_midi_port_init(struct snd_fw_async_midi_port *port, + struct fw_unit *unit, __u64 addr, unsigned int len, + int (*packetize)(struct snd_rawmidi_substream *substream, + __u8 *buf)); +void snd_fw_async_midi_port_destroy(struct snd_fw_async_midi_port *port); + +/** + * snd_fw_async_midi_port_run - run transactions for the async MIDI port + * @port: the asynchronous MIDI port + * @substream: the MIDI substream + */ +static inline void +snd_fw_async_midi_port_run(struct snd_fw_async_midi_port *port, + struct snd_rawmidi_substream *substream) +{ + port->substream = substream; + tasklet_schedule(&port->tasklet); +} + +/** + * snd_fw_async_midi_port_finish - finish the asynchronous MIDI port + * @port: the asynchronous MIDI port + */ +static inline void +snd_fw_async_midi_port_finish(struct snd_fw_async_midi_port *port) +{ + port->substream = NULL; +} + #endif