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Diffstat (limited to 'drivers/fsi/fsi-master.h')
| -rw-r--r-- | drivers/fsi/fsi-master.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/fsi/fsi-master.h b/drivers/fsi/fsi-master.h new file mode 100644 index 000000000..040a7d4cf --- /dev/null +++ b/drivers/fsi/fsi-master.h @@ -0,0 +1,97 @@ +/* + * FSI master definitions. These comprise the core <--> master interface, + * to allow the core to interact with the (hardware-specific) masters. + * + * Copyright (C) IBM Corporation 2016 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef DRIVERS_FSI_MASTER_H +#define DRIVERS_FSI_MASTER_H + +#include <linux/device.h> +#include <linux/mutex.h> + +/* Various protocol delays */ +#define FSI_ECHO_DELAY_CLOCKS 16 /* Number clocks for echo delay */ +#define FSI_SEND_DELAY_CLOCKS 16 /* Number clocks for send delay */ +#define FSI_PRE_BREAK_CLOCKS 50 /* Number clocks to prep for break */ +#define FSI_BREAK_CLOCKS 256 /* Number of clocks to issue break */ +#define FSI_POST_BREAK_CLOCKS 16000 /* Number clocks to set up cfam */ +#define FSI_INIT_CLOCKS 5000 /* Clock out any old data */ +#define FSI_MASTER_DPOLL_CLOCKS 50 /* < 21 will cause slave to hang */ +#define FSI_MASTER_EPOLL_CLOCKS 50 /* Number of clocks for E_POLL retry */ + +/* Various retry maximums */ +#define FSI_CRC_ERR_RETRIES 10 +#define FSI_MASTER_MAX_BUSY 200 +#define FSI_MASTER_MTOE_COUNT 1000 + +/* Command encodings */ +#define FSI_CMD_DPOLL 0x2 +#define FSI_CMD_EPOLL 0x3 +#define FSI_CMD_TERM 0x3f +#define FSI_CMD_ABS_AR 0x4 +#define FSI_CMD_REL_AR 0x5 +#define FSI_CMD_SAME_AR 0x3 /* but only a 2-bit opcode... */ + +/* Slave responses */ +#define FSI_RESP_ACK 0 /* Success */ +#define FSI_RESP_BUSY 1 /* Slave busy */ +#define FSI_RESP_ERRA 2 /* Any (misc) Error */ +#define FSI_RESP_ERRC 3 /* Slave reports master CRC error */ + +/* Misc */ +#define FSI_CRC_SIZE 4 + +/* fsi-master definition and flags */ +#define FSI_MASTER_FLAG_SWCLOCK 0x1 + +struct fsi_master { + struct device dev; + int idx; + int n_links; + int flags; + struct mutex scan_lock; + int (*read)(struct fsi_master *, int link, uint8_t id, + uint32_t addr, void *val, size_t size); + int (*write)(struct fsi_master *, int link, uint8_t id, + uint32_t addr, const void *val, size_t size); + int (*term)(struct fsi_master *, int link, uint8_t id); + int (*send_break)(struct fsi_master *, int link); + int (*link_enable)(struct fsi_master *, int link); + int (*link_config)(struct fsi_master *, int link, + u8 t_send_delay, u8 t_echo_delay); +}; + +#define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev) + +/** + * fsi_master registration & lifetime: the fsi_master_register() and + * fsi_master_unregister() functions will take ownership of the master, and + * ->dev in particular. The registration path performs a get_device(), which + * takes the first reference on the device. Similarly, the unregistration path + * performs a put_device(), which may well drop the last reference. + * + * This means that master implementations *may* need to hold their own + * reference (via get_device()) on master->dev. In particular, if the device's + * ->release callback frees the fsi_master, then fsi_master_unregister will + * invoke this free if no other reference is held. + * + * The same applies for the error path of fsi_master_register; if the call + * fails, dev->release will have been invoked. + */ +extern int fsi_master_register(struct fsi_master *master); +extern void fsi_master_unregister(struct fsi_master *master); + +extern int fsi_master_rescan(struct fsi_master *master); + +#endif /* DRIVERS_FSI_MASTER_H */ |