Commit 490ff95f authored by Ulf Hansson's avatar Ulf Hansson
Browse files

mmc: core: Convert to mmc_poll_for_busy() for HPI commands 



Rather than open coding the polling loop in mmc_interrupt_hpi(), let's
convert to use mmc_poll_for_busy().

Note that, moving to mmc_poll_for_busy() for HPI also improves the
behaviour according to below.

- Adds support for polling via the optional ->card_busy() host ops.
- Require R1_READY_FOR_DATA to be set in the CMD13 response before exiting
  the polling loop.
- Adds a throttling mechanism to avoid CPU hogging when polling.

Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Tested-by: default avatarBaolin Wang <baolin.wang7@gmail.com>
Tested-by: default avatarLudovic Barre <ludovic.barre@st.com>
Reviewed-by: default avatarLudovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200204085449.32585-11-ulf.hansson@linaro.org
parent 9f94d047

drivers/mmc/core/mmc_ops.c

+5 −15
Original line number Diff line number Diff line
@@ -471,6 +471,8 @@ static int mmc_busy_status(struct mmc_card *card, bool retry_crc_err, 
	case MMC_BUSY_ERASE:

		err = R1_STATUS(status) ? -EIO : 0;

		break;

	case MMC_BUSY_HPI:

		break;

	default:

		err = -EINVAL;

	}
@@ -831,6 +833,7 @@ int mmc_bus_test(struct mmc_card *card, u8 bus_width) 


static int mmc_send_hpi_cmd(struct mmc_card *card)

{

	unsigned int busy_timeout_ms = card->ext_csd.out_of_int_time;

	struct mmc_command cmd = {};

	unsigned int opcode;

	int err;
@@ -852,7 +855,8 @@ static int mmc_send_hpi_cmd(struct mmc_card *card) 
		return err;

	}



	return 0;

	/* Let's poll to find out when the HPI request completes. */

	return mmc_poll_for_busy(card, busy_timeout_ms, MMC_BUSY_HPI);

}



/**
@@ -866,7 +870,6 @@ int mmc_interrupt_hpi(struct mmc_card *card) 
{

	int err;

	u32 status;

	unsigned long prg_wait;



	if (!card->ext_csd.hpi_en) {

		pr_info("%s: HPI enable bit unset\n", mmc_hostname(card->host));
@@ -900,19 +903,6 @@ int mmc_interrupt_hpi(struct mmc_card *card) 
	}



	err = mmc_send_hpi_cmd(card);

	if (err)

		goto out;



	prg_wait = jiffies + msecs_to_jiffies(card->ext_csd.out_of_int_time);

	do {

		err = mmc_send_status(card, &status);



		if (!err && R1_CURRENT_STATE(status) == R1_STATE_TRAN)

			break;

		if (time_after(jiffies, prg_wait))

			err = -ETIMEDOUT;

	} while (!err);



out:

	return err;

}

drivers/mmc/core/mmc_ops.h

+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
enum mmc_busy_cmd {

	MMC_BUSY_CMD6,

	MMC_BUSY_ERASE,

	MMC_BUSY_HPI,

};



struct mmc_host;

CRA Git | Maintained and supported by SUSTech CRA and CCSE