1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef SOUND_FIREWIRE_CMP_H_INCLUDED 3 #define SOUND_FIREWIRE_CMP_H_INCLUDED 4 5 #include <linux/mutex.h> 6 #include <linux/types.h> 7 #include "iso-resources.h" 8 9 struct fw_unit; 10 11 enum cmp_direction { 12 CMP_INPUT = 0, 13 CMP_OUTPUT, 14 }; 15 16 /** 17 * struct cmp_connection - manages an isochronous connection to a device 18 * @speed: the connection's actual speed 19 * 20 * This structure manages (using CMP) an isochronous stream between the local 21 * computer and a device's input plug (iPCR) and output plug (oPCR). 22 * 23 * There is no corresponding oPCR created on the local computer, so it is not 24 * possible to overlay connections on top of this one. 25 */ 26 struct cmp_connection { 27 int speed; 28 /* private: */ 29 bool connected; 30 struct mutex mutex; 31 struct fw_iso_resources resources; 32 __be32 last_pcr_value; 33 unsigned int pcr_index; 34 unsigned int max_speed; 35 enum cmp_direction direction; 36 }; 37 38 int cmp_connection_init(struct cmp_connection *connection, 39 struct fw_unit *unit, 40 enum cmp_direction direction, 41 unsigned int pcr_index); 42 int cmp_connection_check_used(struct cmp_connection *connection, bool *used); 43 void cmp_connection_destroy(struct cmp_connection *connection); 44 45 int cmp_connection_reserve(struct cmp_connection *connection, 46 unsigned int max_payload); 47 void cmp_connection_release(struct cmp_connection *connection); 48 49 int cmp_connection_establish(struct cmp_connection *connection); 50 void cmp_connection_break(struct cmp_connection *connection); 51 52 #endif 53