diff options
Diffstat (limited to 'sound/firewire/fireface/ff-transaction.c')
| -rw-r--r-- | sound/firewire/fireface/ff-transaction.c | 295 |
1 files changed, 295 insertions, 0 deletions
diff --git a/sound/firewire/fireface/ff-transaction.c b/sound/firewire/fireface/ff-transaction.c new file mode 100644 index 000000000000..d1b098f8ae42 --- /dev/null +++ b/sound/firewire/fireface/ff-transaction.c @@ -0,0 +1,295 @@ +/* + * ff-transaction.c - a part of driver for RME Fireface series + * + * Copyright (c) 2015-2017 Takashi Sakamoto + * + * Licensed under the terms of the GNU General Public License, version 2. + */ + +#include "ff.h" + +static void finish_transmit_midi_msg(struct snd_ff *ff, unsigned int port, + int rcode) +{ + struct snd_rawmidi_substream *substream = + ACCESS_ONCE(ff->rx_midi_substreams[port]); + + if (rcode_is_permanent_error(rcode)) { + ff->rx_midi_error[port] = true; + return; + } + + if (rcode != RCODE_COMPLETE) { + /* Transfer the message again, immediately. */ + ff->next_ktime[port] = ktime_set(0, 0); + schedule_work(&ff->rx_midi_work[port]); + return; + } + + snd_rawmidi_transmit_ack(substream, ff->rx_bytes[port]); + ff->rx_bytes[port] = 0; + + if (!snd_rawmidi_transmit_empty(substream)) + schedule_work(&ff->rx_midi_work[port]); +} + +static void finish_transmit_midi0_msg(struct fw_card *card, int rcode, + void *data, size_t length, + void *callback_data) +{ + struct snd_ff *ff = + container_of(callback_data, struct snd_ff, transactions[0]); + finish_transmit_midi_msg(ff, 0, rcode); +} + +static void finish_transmit_midi1_msg(struct fw_card *card, int rcode, + void *data, size_t length, + void *callback_data) +{ + struct snd_ff *ff = + container_of(callback_data, struct snd_ff, transactions[1]); + finish_transmit_midi_msg(ff, 1, rcode); +} + +static inline void fill_midi_buf(struct snd_ff *ff, unsigned int port, + unsigned int index, u8 byte) +{ + ff->msg_buf[port][index] = cpu_to_le32(byte); +} + +static void transmit_midi_msg(struct snd_ff *ff, unsigned int port) +{ + struct snd_rawmidi_substream *substream = + ACCESS_ONCE(ff->rx_midi_substreams[port]); + u8 *buf = (u8 *)ff->msg_buf[port]; + int i, len; + + struct fw_device *fw_dev = fw_parent_device(ff->unit); + unsigned long long addr; + int generation; + fw_transaction_callback_t callback; + + if (substream == NULL || snd_rawmidi_transmit_empty(substream)) + return; + + if (ff->rx_bytes[port] > 0 || ff->rx_midi_error[port]) + return; + + /* Do it in next chance. */ + if (ktime_after(ff->next_ktime[port], ktime_get())) { + schedule_work(&ff->rx_midi_work[port]); + return; + } + + len = snd_rawmidi_transmit_peek(substream, buf, + SND_FF_MAXIMIM_MIDI_QUADS); + if (len <= 0) + return; + + for (i = len - 1; i >= 0; i--) + fill_midi_buf(ff, port, i, buf[i]); + + if (port == 0) { + addr = ff->spec->protocol->midi_rx_port_0_reg; + callback = finish_transmit_midi0_msg; + } else { + addr = ff->spec->protocol->midi_rx_port_1_reg; + callback = finish_transmit_midi1_msg; + } + + /* Set interval to next transaction. */ + ff->next_ktime[port] = ktime_add_ns(ktime_get(), + len * 8 * NSEC_PER_SEC / 31250); + ff->rx_bytes[port] = len; + + /* + * In Linux FireWire core, when generation is updated with memory + * barrier, node id has already been updated. In this module, After + * this smp_rmb(), load/store instructions to memory are completed. + * Thus, both of generation and node id are available with recent + * values. This is a light-serialization solution to handle bus reset + * events on IEEE 1394 bus. + */ + generation = fw_dev->generation; + smp_rmb(); + fw_send_request(fw_dev->card, &ff->transactions[port], + TCODE_WRITE_BLOCK_REQUEST, + fw_dev->node_id, generation, fw_dev->max_speed, + addr, &ff->msg_buf[port], len * 4, + callback, &ff->transactions[port]); +} + +static void transmit_midi0_msg(struct work_struct *work) +{ + struct snd_ff *ff = container_of(work, struct snd_ff, rx_midi_work[0]); + + transmit_midi_msg(ff, 0); +} + +static void transmit_midi1_msg(struct work_struct *work) +{ + struct snd_ff *ff = container_of(work, struct snd_ff, rx_midi_work[1]); + + transmit_midi_msg(ff, 1); +} + +static void handle_midi_msg(struct fw_card *card, struct fw_request *request, + int tcode, int destination, int source, + int generation, unsigned long long offset, + void *data, size_t length, void *callback_data) +{ + struct snd_ff *ff = callback_data; + __le32 *buf = data; + u32 quad; + u8 byte; + unsigned int index; + struct snd_rawmidi_substream *substream; + int i; + + fw_send_response(card, request, RCODE_COMPLETE); + + for (i = 0; i < length / 4; i++) { + quad = le32_to_cpu(buf[i]); + + /* Message in first port. */ + /* + * This value may represent the index of this unit when the same + * units are on the same IEEE 1394 bus. This driver doesn't use + * it. + */ + index = (quad >> 8) & 0xff; + if (index > 0) { + substream = ACCESS_ONCE(ff->tx_midi_substreams[0]); + if (substream != NULL) { + byte = quad & 0xff; + snd_rawmidi_receive(substream, &byte, 1); + } + } + + /* Message in second port. */ + index = (quad >> 24) & 0xff; + if (index > 0) { + substream = ACCESS_ONCE(ff->tx_midi_substreams[1]); + if (substream != NULL) { + byte = (quad >> 16) & 0xff; + snd_rawmidi_receive(substream, &byte, 1); + } + } + } +} + +static int allocate_own_address(struct snd_ff *ff, int i) +{ + struct fw_address_region midi_msg_region; + int err; + + ff->async_handler.length = SND_FF_MAXIMIM_MIDI_QUADS * 4; + ff->async_handler.address_callback = handle_midi_msg; + ff->async_handler.callback_data = ff; + + midi_msg_region.start = 0x000100000000ull * i; + midi_msg_region.end = midi_msg_region.start + ff->async_handler.length; + + err = fw_core_add_address_handler(&ff->async_handler, &midi_msg_region); + if (err >= 0) { + /* Controllers are allowed to register this region. */ + if (ff->async_handler.offset & 0x0000ffffffff) { + fw_core_remove_address_handler(&ff->async_handler); + err = -EAGAIN; + } + } + + return err; +} + +/* + * The configuration to start asynchronous transactions for MIDI messages is in + * 0x'0000'8010'051c. This register includes the other options, thus this driver + * doesn't touch it and leaves the decision to userspace. The userspace MUST add + * 0x04000000 to write transactions to the register to receive any MIDI + * messages. + * + * Here, I just describe MIDI-related offsets of the register, in little-endian + * order. + * + * Controllers are allowed to register higher 4 bytes of address to receive + * the transactions. The register is 0x'0000'8010'03f4. On the other hand, the + * controllers are not allowed to register lower 4 bytes of the address. They + * are forced to select from 4 options by writing corresponding bits to + * 0x'0000'8010'051c. + * + * The 3rd-6th bits in MSB of this register are used to indicate lower 4 bytes + * of address to which the device transferrs the transactions. + * - 6th: 0x'....'....'0000'0180 + * - 5th: 0x'....'....'0000'0100 + * - 4th: 0x'....'....'0000'0080 + * - 3rd: 0x'....'....'0000'0000 + * + * This driver configure 0x'....'....'0000'0000 for units to receive MIDI + * messages. 3rd bit of the register should be configured, however this driver + * deligates this task to user space applications due to a restriction that + * this register is write-only and the other bits have own effects. + * + * The 1st and 2nd bits in LSB of this register are used to cancel transferring + * asynchronous transactions. These two bits have the same effect. + * - 1st/2nd: cancel transferring + */ +int snd_ff_transaction_reregister(struct snd_ff *ff) +{ + struct fw_card *fw_card = fw_parent_device(ff->unit)->card; + u32 addr; + __le32 reg; + + /* + * Controllers are allowed to register its node ID and upper 2 byte of + * local address to listen asynchronous transactions. + */ + addr = (fw_card->node_id << 16) | (ff->async_handler.offset >> 32); + reg = cpu_to_le32(addr); + return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST, + ff->spec->protocol->midi_high_addr_reg, + ®, sizeof(reg), 0); +} + +int snd_ff_transaction_register(struct snd_ff *ff) +{ + int i, err; + + /* + * Allocate in Memory Space of IEC 13213, but lower 4 byte in LSB should + * be zero due to device specification. + */ + for (i = 0; i < 0xffff; i++) { + err = allocate_own_address(ff, i); + if (err != -EBUSY && err != -EAGAIN) + break; + } + if (err < 0) + return err; + + err = snd_ff_transaction_reregister(ff); + if (err < 0) + return err; + + INIT_WORK(&ff->rx_midi_work[0], transmit_midi0_msg); + INIT_WORK(&ff->rx_midi_work[1], transmit_midi1_msg); + + return 0; +} + +void snd_ff_transaction_unregister(struct snd_ff *ff) +{ + __le32 reg; + + if (ff->async_handler.callback_data == NULL) + return; + ff->async_handler.callback_data = NULL; + + /* Release higher 4 bytes of address. */ + reg = cpu_to_le32(0x00000000); + snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST, + ff->spec->protocol->midi_high_addr_reg, + ®, sizeof(reg), 0); + + fw_core_remove_address_handler(&ff->async_handler); +} |