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Diffstat (limited to 'include/linux/fsl/bestcomm/bestcomm.h')
| -rw-r--r-- | include/linux/fsl/bestcomm/bestcomm.h | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/include/linux/fsl/bestcomm/bestcomm.h b/include/linux/fsl/bestcomm/bestcomm.h new file mode 100644 index 000000000..a0e2e6b19 --- /dev/null +++ b/include/linux/fsl/bestcomm/bestcomm.h @@ -0,0 +1,213 @@ +/* + * Public header for the MPC52xx processor BestComm driver + * + * + * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com> + * Copyright (C) 2005 Varma Electronics Oy, + * ( by Andrey Volkov <avolkov@varma-el.com> ) + * Copyright (C) 2003-2004 MontaVista, Software, Inc. + * ( by Dale Farnsworth <dfarnsworth@mvista.com> ) + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +#ifndef __BESTCOMM_H__ +#define __BESTCOMM_H__ + +/** + * struct bcom_bd - Structure describing a generic BestComm buffer descriptor + * @status: The current status of this buffer. Exact meaning depends on the + * task type + * @data: An array of u32 extra data. Size of array is task dependent. + * + * Note: Don't dereference a bcom_bd pointer as an array. The size of the + * bcom_bd is variable. Use bcom_get_bd() instead. + */ +struct bcom_bd { + u32 status; + u32 data[0]; /* variable payload size */ +}; + +/* ======================================================================== */ +/* Generic task management */ +/* ======================================================================== */ + +/** + * struct bcom_task - Structure describing a loaded BestComm task + * + * This structure is never built by the driver it self. It's built and + * filled the intermediate layer of the BestComm API, the task dependent + * support code. + * + * Most likely you don't need to poke around inside this structure. The + * fields are exposed in the header just for the sake of inline functions + */ +struct bcom_task { + unsigned int tasknum; + unsigned int flags; + int irq; + + struct bcom_bd *bd; + phys_addr_t bd_pa; + void **cookie; + unsigned short index; + unsigned short outdex; + unsigned int num_bd; + unsigned int bd_size; + + void* priv; +}; + +#define BCOM_FLAGS_NONE 0x00000000ul +#define BCOM_FLAGS_ENABLE_TASK (1ul << 0) + +/** + * bcom_enable - Enable a BestComm task + * @tsk: The BestComm task structure + * + * This function makes sure the given task is enabled and can be run + * by the BestComm engine as needed + */ +extern void bcom_enable(struct bcom_task *tsk); + +/** + * bcom_disable - Disable a BestComm task + * @tsk: The BestComm task structure + * + * This function disable a given task, making sure it's not executed + * by the BestComm engine. + */ +extern void bcom_disable(struct bcom_task *tsk); + + +/** + * bcom_get_task_irq - Returns the irq number of a BestComm task + * @tsk: The BestComm task structure + */ +static inline int +bcom_get_task_irq(struct bcom_task *tsk) { + return tsk->irq; +} + +/* ======================================================================== */ +/* BD based tasks helpers */ +/* ======================================================================== */ + +#define BCOM_BD_READY 0x40000000ul + +/** _bcom_next_index - Get next input index. + * @tsk: pointer to task structure + * + * Support function; Device drivers should not call this + */ +static inline int +_bcom_next_index(struct bcom_task *tsk) +{ + return ((tsk->index + 1) == tsk->num_bd) ? 0 : tsk->index + 1; +} + +/** _bcom_next_outdex - Get next output index. + * @tsk: pointer to task structure + * + * Support function; Device drivers should not call this + */ +static inline int +_bcom_next_outdex(struct bcom_task *tsk) +{ + return ((tsk->outdex + 1) == tsk->num_bd) ? 0 : tsk->outdex + 1; +} + +/** + * bcom_queue_empty - Checks if a BestComm task BD queue is empty + * @tsk: The BestComm task structure + */ +static inline int +bcom_queue_empty(struct bcom_task *tsk) +{ + return tsk->index == tsk->outdex; +} + +/** + * bcom_queue_full - Checks if a BestComm task BD queue is full + * @tsk: The BestComm task structure + */ +static inline int +bcom_queue_full(struct bcom_task *tsk) +{ + return tsk->outdex == _bcom_next_index(tsk); +} + +/** + * bcom_get_bd - Get a BD from the queue + * @tsk: The BestComm task structure + * index: Index of the BD to fetch + */ +static inline struct bcom_bd +*bcom_get_bd(struct bcom_task *tsk, unsigned int index) +{ + /* A cast to (void*) so the address can be incremented by the + * real size instead of by sizeof(struct bcom_bd) */ + return ((void *)tsk->bd) + (index * tsk->bd_size); +} + +/** + * bcom_buffer_done - Checks if a BestComm + * @tsk: The BestComm task structure + */ +static inline int +bcom_buffer_done(struct bcom_task *tsk) +{ + struct bcom_bd *bd; + if (bcom_queue_empty(tsk)) + return 0; + + bd = bcom_get_bd(tsk, tsk->outdex); + return !(bd->status & BCOM_BD_READY); +} + +/** + * bcom_prepare_next_buffer - clear status of next available buffer. + * @tsk: The BestComm task structure + * + * Returns pointer to next buffer descriptor + */ +static inline struct bcom_bd * +bcom_prepare_next_buffer(struct bcom_task *tsk) +{ + struct bcom_bd *bd; + + bd = bcom_get_bd(tsk, tsk->index); + bd->status = 0; /* cleanup last status */ + return bd; +} + +static inline void +bcom_submit_next_buffer(struct bcom_task *tsk, void *cookie) +{ + struct bcom_bd *bd = bcom_get_bd(tsk, tsk->index); + + tsk->cookie[tsk->index] = cookie; + mb(); /* ensure the bd is really up-to-date */ + bd->status |= BCOM_BD_READY; + tsk->index = _bcom_next_index(tsk); + if (tsk->flags & BCOM_FLAGS_ENABLE_TASK) + bcom_enable(tsk); +} + +static inline void * +bcom_retrieve_buffer(struct bcom_task *tsk, u32 *p_status, struct bcom_bd **p_bd) +{ + void *cookie = tsk->cookie[tsk->outdex]; + struct bcom_bd *bd = bcom_get_bd(tsk, tsk->outdex); + + if (p_status) + *p_status = bd->status; + if (p_bd) + *p_bd = bd; + tsk->outdex = _bcom_next_outdex(tsk); + return cookie; +} + +#endif /* __BESTCOMM_H__ */ |