1 files changed, 89 insertions, 6 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index d083d2e57abd..f0ed0afe033d 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -120,6 +120,24 @@ static inline void mmc_should_fail_request(struct mmc_host *host,
 
 #endif /* CONFIG_FAIL_MMC_REQUEST */
 
+static inline void mmc_complete_cmd(struct mmc_request *mrq)
+{
+	if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
+		complete_all(&mrq->cmd_completion);
+}
+
+void mmc_command_done(struct mmc_host *host, struct mmc_request *mrq)
+{
+	if (!mrq->cap_cmd_during_tfr)
+		return;
+
+	mmc_complete_cmd(mrq);
+
+	pr_debug("%s: cmd done, tfr ongoing (CMD%u)\n",
+		 mmc_hostname(host), mrq->cmd->opcode);
+}
+EXPORT_SYMBOL(mmc_command_done);
+
 /**
  *	mmc_request_done - finish processing an MMC request
  *	@host: MMC host which completed request
@@ -146,6 +164,11 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
 			cmd->retries = 0;
 	}
 
+	if (host->ongoing_mrq == mrq)
+		host->ongoing_mrq = NULL;
+
+	mmc_complete_cmd(mrq);
+
 	trace_mmc_request_done(host, mrq);
 
 	if (err && cmd->retries && !mmc_card_removed(host->card)) {
@@ -158,7 +181,8 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
 	} else {
 		mmc_should_fail_request(host, mrq);
 
-		led_trigger_event(host->led, LED_OFF);
+		if (!host->ongoing_mrq)
+			led_trigger_event(host->led, LED_OFF);
 
 		if (mrq->sbc) {
 			pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
@@ -223,6 +247,15 @@ static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
 		}
 	}
 
+	if (mrq->cap_cmd_during_tfr) {
+		host->ongoing_mrq = mrq;
+		/*
+		 * Retry path could come through here without having waiting on
+		 * cmd_completion, so ensure it is reinitialised.
+		 */
+		reinit_completion(&mrq->cmd_completion);
+	}
+
 	trace_mmc_request_start(host, mrq);
 
 	host->ops->request(host, mrq);
@@ -389,6 +422,18 @@ static void mmc_wait_done(struct mmc_request *mrq)
 	complete(&mrq->completion);
 }
 
+static inline void mmc_wait_ongoing_tfr_cmd(struct mmc_host *host)
+{
+	struct mmc_request *ongoing_mrq = READ_ONCE(host->ongoing_mrq);
+
+	/*
+	 * If there is an ongoing transfer, wait for the command line to become
+	 * available.
+	 */
+	if (ongoing_mrq && !completion_done(&ongoing_mrq->cmd_completion))
+		wait_for_completion(&ongoing_mrq->cmd_completion);
+}
+
 /*
  *__mmc_start_data_req() - starts data request
  * @host: MMC host to start the request
@@ -396,17 +441,24 @@ static void mmc_wait_done(struct mmc_request *mrq)
  *
  * Sets the done callback to be called when request is completed by the card.
  * Starts data mmc request execution
+ * If an ongoing transfer is already in progress, wait for the command line
+ * to become available before sending another command.
  */
 static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
 {
 	int err;
 
+	mmc_wait_ongoing_tfr_cmd(host);
+
 	mrq->done = mmc_wait_data_done;
 	mrq->host = host;
 
+	init_completion(&mrq->cmd_completion);
+
 	err = mmc_start_request(host, mrq);
 	if (err) {
 		mrq->cmd->error = err;
+		mmc_complete_cmd(mrq);
 		mmc_wait_data_done(mrq);
 	}
 
@@ -417,12 +469,17 @@ static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
 {
 	int err;
 
+	mmc_wait_ongoing_tfr_cmd(host);
+
 	init_completion(&mrq->completion);
 	mrq->done = mmc_wait_done;
 
+	init_completion(&mrq->cmd_completion);
+
 	err = mmc_start_request(host, mrq);
 	if (err) {
 		mrq->cmd->error = err;
+		mmc_complete_cmd(mrq);
 		complete(&mrq->completion);
 	}
 
@@ -486,8 +543,7 @@ static int mmc_wait_for_data_req_done(struct mmc_host *host,
 	return err;
 }
 
-static void mmc_wait_for_req_done(struct mmc_host *host,
-				  struct mmc_request *mrq)
+void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq)
 {
 	struct mmc_command *cmd;
 
@@ -528,6 +584,28 @@ static void mmc_wait_for_req_done(struct mmc_host *host,
 
 	mmc_retune_release(host);
 }
+EXPORT_SYMBOL(mmc_wait_for_req_done);
+
+/**
+ *	mmc_is_req_done - Determine if a 'cap_cmd_during_tfr' request is done
+ *	@host: MMC host
+ *	@mrq: MMC request
+ *
+ *	mmc_is_req_done() is used with requests that have
+ *	mrq->cap_cmd_during_tfr = true. mmc_is_req_done() must be called after
+ *	starting a request and before waiting for it to complete. That is,
+ *	either in between calls to mmc_start_req(), or after mmc_wait_for_req()
+ *	and before mmc_wait_for_req_done(). If it is called at other times the
+ *	result is not meaningful.
+ */
+bool mmc_is_req_done(struct mmc_host *host, struct mmc_request *mrq)
+{
+	if (host->areq)
+		return host->context_info.is_done_rcv;
+	else
+		return completion_done(&mrq->completion);
+}
+EXPORT_SYMBOL(mmc_is_req_done);
 
 /**
  *	mmc_pre_req - Prepare for a new request
@@ -648,13 +726,18 @@ EXPORT_SYMBOL(mmc_start_req);
  *	@mrq: MMC request to start
  *
  *	Start a new MMC custom command request for a host, and wait
- *	for the command to complete. Does not attempt to parse the
- *	response.
+ *	for the command to complete. In the case of 'cap_cmd_during_tfr'
+ *	requests, the transfer is ongoing and the caller can issue further
+ *	commands that do not use the data lines, and then wait by calling
+ *	mmc_wait_for_req_done().
+ *	Does not attempt to parse the response.
  */
 void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
 {
 	__mmc_start_req(host, mrq);
-	mmc_wait_for_req_done(host, mrq);
+
+	if (!mrq->cap_cmd_during_tfr)
+		mmc_wait_for_req_done(host, mrq);
 }
 EXPORT_SYMBOL(mmc_wait_for_req);