From:   Ulf Hansson <ulf.hansson@linaro.org>
To:     linux-mmc@vger.kernel.org, Ulf Hansson <ulf.hansson@linaro.org>
Cc:     Adrian Hunter <adrian.hunter@intel.com>,
        Avri Altman <avri.altman@wdc.com>,
        Christian Lohle <cloehle@hyperstone.com>,
        linux-kernel@vger.kernel.org
Subject: [PATCH] mmc: core: Align to common busy polling behaviour for mmc ioctls
Date:   Mon, 13 Feb 2023 14:37:07 +0100
Message-Id: <20230213133707.27857-1-ulf.hansson@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Let's align to the common busy polling behaviour for mmc ioctls, by
updating the below two corresponding parts, that comes into play when using
an R1B response for a command.

*) A command with an R1B response should be prepared by calling
mmc_prepare_busy_cmd(), which make us respects the host's busy timeout
constraints.
**) When an R1B response is being used and the host also supports HW busy
detection, we should skip to poll for busy completion.

Suggested-by: Christian Loehle <cloehle@hyperstone.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/mmc/core/block.c   | 25 +++++++++++++++++--------
 drivers/mmc/core/mmc_ops.c |  1 +
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 20da7ed43e6d..672ab90c4b2d 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -470,6 +470,8 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
 	struct mmc_data data = {};
 	struct mmc_request mrq = {};
 	struct scatterlist sg;
+	bool r1b_resp, use_r1b_resp = false;
+	unsigned int busy_timeout_ms;
 	int err;
 	unsigned int target_part;
 
@@ -545,6 +547,13 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
 	    (cmd.opcode == MMC_SWITCH))
 		return mmc_sanitize(card, idata->ic.cmd_timeout_ms);
 
+	/* If it's an R1B response we need some more preparations. */
+	busy_timeout_ms = idata->ic.cmd_timeout_ms ? : MMC_BLK_TIMEOUT_MS;
+	r1b_resp = (cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B;
+	if (r1b_resp)
+		use_r1b_resp = mmc_prepare_busy_cmd(card->host, &cmd,
+						    busy_timeout_ms);
+
 	mmc_wait_for_req(card->host, &mrq);
 	memcpy(&idata->ic.response, cmd.resp, sizeof(cmd.resp));
 
@@ -596,14 +605,14 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
 	if (idata->ic.postsleep_min_us)
 		usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us);
 
-	if (idata->rpmb || (cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) {
-		/*
-		 * Ensure RPMB/R1B command has completed by polling CMD13 "Send Status". Here we
-		 * allow to override the default timeout value if a custom timeout is specified.
-		 */
-		err = mmc_poll_for_busy(card, idata->ic.cmd_timeout_ms ? : MMC_BLK_TIMEOUT_MS,
-					false, MMC_BUSY_IO);
-	}
+	/* No need to poll when using HW busy detection. */
+	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)
+		return 0;
+
+	/* Ensure RPMB/R1B command has completed by polling with CMD13. */
+	if (idata->rpmb || r1b_resp)
+		err = mmc_poll_for_busy(card, busy_timeout_ms, false,
+					MMC_BUSY_IO);
 
 	return err;
 }
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 81c55bfd6e0c..3b3adbddf664 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -575,6 +575,7 @@ bool mmc_prepare_busy_cmd(struct mmc_host *host, struct mmc_command *cmd,
 	cmd->busy_timeout = timeout_ms;
 	return true;
 }
+EXPORT_SYMBOL_GPL(mmc_prepare_busy_cmd);
 
 /**
  *	__mmc_switch - modify EXT_CSD register
-- 
2.34.1