41 lines
1.5 KiB
Diff
41 lines
1.5 KiB
Diff
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From b68b4448dc37e5fd510f1bb9bbd62722ad497f41 Mon Sep 17 00:00:00 2001
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From: Daniel Santos <daniel.santos@pobox.com>
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Date: Sun, 5 Jan 2014 17:39:26 -0600
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Subject: [PATCH 168/174] spidev: fix hang when transfer_one_message fails
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commit e120cc0dcf2880a4c5c0a6cb27b655600a1cfa1d upstream.
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This corrects a problem in spi_pump_messages() that leads to an spi
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message hanging forever when a call to transfer_one_message() fails.
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This failure occurs in my MCP2210 driver when the cs_change bit is set
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on the last transfer in a message, an operation which the hardware does
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not support.
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Rationale
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Since the transfer_one_message() returns an int, we must presume that it
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may fail. If transfer_one_message() should never fail, it should return
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void. Thus, calls to transfer_one_message() should properly manage a
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failure.
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Fixes: ffbbdd21329f3 (spi: create a message queueing infrastructure)
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Signed-off-by: Daniel Santos <daniel.santos@pobox.com>
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Signed-off-by: Mark Brown <broonie@linaro.org>
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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---
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drivers/spi/spi.c | 4 +++-
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1 file changed, 3 insertions(+), 1 deletion(-)
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--- a/drivers/spi/spi.c
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+++ b/drivers/spi/spi.c
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@@ -584,7 +584,9 @@ static void spi_pump_messages(struct kth
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ret = master->transfer_one_message(master, master->cur_msg);
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if (ret) {
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dev_err(&master->dev,
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- "failed to transfer one message from queue\n");
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+ "failed to transfer one message from queue: %d\n", ret);
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+ master->cur_msg->status = ret;
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+ spi_finalize_current_message(master);
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return;
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}
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}
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