Commit e7f3d222 authored Jan 10, 2014 by Ulf Hansson Committed by Chris Ball Feb 23, 2014

mmc: mmci: Handle CMD irq before DATA irq



In case of a read operation both MCI_CMDRESPEND and MCI_DATAEND can be
set in the status register when entering the interrupt handler. This is
due to that the card start sending data before the host has
acknowledged the command response.

To resolve the issue for this scenario, we must start by handling the
CMD irq instead of the DATA irq. The reason is beacuse the completion
of the DATA irq will not respect the current command and then causing
it to be garbled.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Johan Rudholm <jrudholm@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>

parent bb5cba40

drivers/mmc/host/mmci.c

+5 −4

Original line number	Diff line number	Diff line
		@@ -1144,16 +1144,17 @@ static irqreturn_t mmci_irq(int irq, void *dev_id)

		dev_dbg(mmc_dev(host->mmc), "irq0 (data+cmd) %08x\n", status);

		cmd = host->cmd;
		if (status & (MCI_CMDCRCFAIL\|MCI_CMDTIMEOUT\|MCI_CMDSENT\|
		MCI_CMDRESPEND) && cmd)
		mmci_cmd_irq(host, cmd, status);

		data = host->data;
		if (status & (MCI_DATACRCFAIL\|MCI_DATATIMEOUT\|MCI_STARTBITERR\|
		MCI_TXUNDERRUN\|MCI_RXOVERRUN\|MCI_DATAEND\|
		MCI_DATABLOCKEND) && data)
		mmci_data_irq(host, data, status);

		cmd = host->cmd;
		if (status & (MCI_CMDCRCFAIL\|MCI_CMDTIMEOUT\|MCI_CMDSENT\|MCI_CMDRESPEND) && cmd)
		mmci_cmd_irq(host, cmd, status);

		ret = 1;
		} while (status);

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