diff options
| -rw-r--r-- | drivers/mmc/core/core.c | 113 | ||||
| -rw-r--r-- | include/linux/mmc/core.h | 6 | ||||
| -rw-r--r-- | include/linux/mmc/host.h | 21 |
3 files changed, 129 insertions, 11 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index ac82865b8c2..ab36c7b491f 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -198,9 +198,109 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq) static void mmc_wait_done(struct mmc_request *mrq) { - complete(mrq->done_data); + complete(&mrq->completion); } +static void __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq) +{ + init_completion(&mrq->completion); + mrq->done = mmc_wait_done; + mmc_start_request(host, mrq); +} + +static void mmc_wait_for_req_done(struct mmc_host *host, + struct mmc_request *mrq) +{ + wait_for_completion(&mrq->completion); +} + +/** + * mmc_pre_req - Prepare for a new request + * @host: MMC host to prepare command + * @mrq: MMC request to prepare for + * @is_first_req: true if there is no previous started request + * that may run in parellel to this call, otherwise false + * + * mmc_pre_req() is called in prior to mmc_start_req() to let + * host prepare for the new request. Preparation of a request may be + * performed while another request is running on the host. + */ +static void mmc_pre_req(struct mmc_host *host, struct mmc_request *mrq, + bool is_first_req) +{ + if (host->ops->pre_req) + host->ops->pre_req(host, mrq, is_first_req); +} + +/** + * mmc_post_req - Post process a completed request + * @host: MMC host to post process command + * @mrq: MMC request to post process for + * @err: Error, if non zero, clean up any resources made in pre_req + * + * Let the host post process a completed request. Post processing of + * a request may be performed while another reuqest is running. + */ +static void mmc_post_req(struct mmc_host *host, struct mmc_request *mrq, + int err) +{ + if (host->ops->post_req) + host->ops->post_req(host, mrq, err); +} + +/** + * mmc_start_req - start a non-blocking request + * @host: MMC host to start command + * @areq: async request to start + * @error: out parameter returns 0 for success, otherwise non zero + * + * Start a new MMC custom command request for a host. + * If there is on ongoing async request wait for completion + * of that request and start the new one and return. + * Does not wait for the new request to complete. + * + * Returns the completed request, NULL in case of none completed. + * Wait for the an ongoing request (previoulsy started) to complete and + * return the completed request. If there is no ongoing request, NULL + * is returned without waiting. NULL is not an error condition. + */ +struct mmc_async_req *mmc_start_req(struct mmc_host *host, + struct mmc_async_req *areq, int *error) +{ + int err = 0; + struct mmc_async_req *data = host->areq; + + /* Prepare a new request */ + if (areq) + mmc_pre_req(host, areq->mrq, !host->areq); + + if (host->areq) { + mmc_wait_for_req_done(host, host->areq->mrq); + err = host->areq->err_check(host->card, host->areq); + if (err) { + mmc_post_req(host, host->areq->mrq, 0); + if (areq) + mmc_post_req(host, areq->mrq, -EINVAL); + + host->areq = NULL; + goto out; + } + } + + if (areq) + __mmc_start_req(host, areq->mrq); + + if (host->areq) + mmc_post_req(host, host->areq->mrq, 0); + + host->areq = areq; + out: + if (error) + *error = err; + return data; +} +EXPORT_SYMBOL(mmc_start_req); + /** * mmc_wait_for_req - start a request and wait for completion * @host: MMC host to start command @@ -212,16 +312,9 @@ static void mmc_wait_done(struct mmc_request *mrq) */ void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq) { - DECLARE_COMPLETION_ONSTACK(complete); - - mrq->done_data = &complete; - mrq->done = mmc_wait_done; - - mmc_start_request(host, mrq); - - wait_for_completion(&complete); + __mmc_start_req(host, mrq); + mmc_wait_for_req_done(host, mrq); } - EXPORT_SYMBOL(mmc_wait_for_req); /** diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index 86d81cf75b7..b8b1b7a311f 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -117,6 +117,7 @@ struct mmc_data { unsigned int sg_len; /* size of scatter list */ struct scatterlist *sg; /* I/O scatter list */ + s32 host_cookie; /* host private data */ }; struct mmc_request { @@ -125,13 +126,16 @@ struct mmc_request { struct mmc_data *data; struct mmc_command *stop; - void *done_data; /* completion data */ + struct completion completion; void (*done)(struct mmc_request *);/* completion function */ }; struct mmc_host; struct mmc_card; +struct mmc_async_req; +extern struct mmc_async_req *mmc_start_req(struct mmc_host *, + struct mmc_async_req *, int *); extern void mmc_wait_for_req(struct mmc_host *, struct mmc_request *); extern int mmc_wait_for_cmd(struct mmc_host *, struct mmc_command *, int); extern int mmc_app_cmd(struct mmc_host *, struct mmc_card *); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index c67d19b5542..9f9a4c64cde 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -106,6 +106,15 @@ struct mmc_host_ops { */ int (*enable)(struct mmc_host *host); int (*disable)(struct mmc_host *host, int lazy); + /* + * It is optional for the host to implement pre_req and post_req in + * order to support double buffering of requests (prepare one + * request while another request is active). + */ + void (*post_req)(struct mmc_host *host, struct mmc_request *req, + int err); + void (*pre_req)(struct mmc_host *host, struct mmc_request *req, + bool is_first_req); void (*request)(struct mmc_host *host, struct mmc_request *req); /* * Avoid calling these three functions too often or in a "fast path", @@ -144,6 +153,16 @@ struct mmc_host_ops { struct mmc_card; struct device; +struct mmc_async_req { + /* active mmc request */ + struct mmc_request *mrq; + /* + * Check error status of completed mmc request. + * Returns 0 if success otherwise non zero. + */ + int (*err_check) (struct mmc_card *, struct mmc_async_req *); +}; + struct mmc_host { struct device *parent; struct device class_dev; @@ -282,6 +301,8 @@ struct mmc_host { struct dentry *debugfs_root; + struct mmc_async_req *areq; /* active async req */ + unsigned long private[0] ____cacheline_aligned; }; |