linux/drivers/mmc/host/mmc_hsq.h
Baolin Wang 6db96e5810 mmc: host: Introduce the request_atomic() for the host
The SD host controller can process one request in the atomic context if
the card is nonremovable, which means we can submit next request in the
irq hard handler when using the MMC host software queue to reduce the
latency. Thus this patch adds a new API request_atomic() for the host
controller, as well as adding support for host software queue to submit
a request by the new request_atomic() API.

Moreover there is an unusual case that the card is busy when trying to
send a command, and we can not polling the card status in interrupt
context by using request_atomic() to dispatch requests. Thus we should
queue a work to try again in the non-atomic context in case the host
releases the busy signal later.

Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/a344e27e506cb2329073cbd5cf65e15cc3cbeba9.1586744073.git.baolin.wang7@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-05-28 11:20:59 +02:00

32 lines
648 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef LINUX_MMC_HSQ_H
#define LINUX_MMC_HSQ_H
struct hsq_slot {
struct mmc_request *mrq;
};
struct mmc_hsq {
struct mmc_host *mmc;
struct mmc_request *mrq;
wait_queue_head_t wait_queue;
struct hsq_slot *slot;
spinlock_t lock;
struct work_struct retry_work;
int next_tag;
int num_slots;
int qcnt;
bool enabled;
bool waiting_for_idle;
bool recovery_halt;
};
int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc);
void mmc_hsq_suspend(struct mmc_host *mmc);
int mmc_hsq_resume(struct mmc_host *mmc);
bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq);
#endif