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spi: Deal with slaves that return from transfer_one() unfinished

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Some drivers, such as spi-pxa2xx return from the transfer_one callback
immediately, idicating that the transfer will be finished asynchronously.

Normally, spi_transfer_one_message() synchronously waits for the
transfer to finish with wait_for_completion_timeout(). For slaves, we
don't want the transaction to time out as it can complete in a long time
in future. Use wait_for_completion_interruptible() instead.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Lubomir Rintel 2018-11-13 11:22:24 +01:00 committed by Mark Brown
parent aa66478aa5
commit 810923f3bf
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GPG key ID: 24D68B725D5487D0
1 changed files with 39 additions and 23 deletions
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62
drivers/spi/spi.c
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@ -1037,6 +1037,42 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
return __spi_map_msg(ctlr, msg); return __spi_map_msg(ctlr, msg);
} }
static int spi_transfer_wait(struct spi_controller *ctlr,
struct spi_message *msg,
struct spi_transfer *xfer)
{
struct spi_statistics *statm = &ctlr->statistics;
struct spi_statistics *stats = &msg->spi->statistics;
unsigned long long ms = 1;
if (spi_controller_is_slave(ctlr)) {
if (wait_for_completion_interruptible(&ctlr->xfer_completion)) {
dev_dbg(&msg->spi->dev, "SPI transfer interrupted\n");
return -EINTR;
}
} else {
ms = 8LL * 1000LL * xfer->len;
do_div(ms, xfer->speed_hz);
ms += ms + 200; /* some tolerance */
if (ms > UINT_MAX)
ms = UINT_MAX;
ms = wait_for_completion_timeout(&ctlr->xfer_completion,
msecs_to_jiffies(ms));
if (ms == 0) {
SPI_STATISTICS_INCREMENT_FIELD(statm, timedout);
SPI_STATISTICS_INCREMENT_FIELD(stats, timedout);
dev_err(&msg->spi->dev,
"SPI transfer timed out\n");
return -ETIMEDOUT;
}
}
return 0;
}
/* /*
* spi_transfer_one_message - Default implementation of transfer_one_message() * spi_transfer_one_message - Default implementation of transfer_one_message()
* *
@ -1050,7 +1086,6 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
struct spi_transfer *xfer; struct spi_transfer *xfer;
bool keep_cs = false; bool keep_cs = false;
int ret = 0; int ret = 0;
unsigned long long ms = 1;
struct spi_statistics *statm = &ctlr->statistics; struct spi_statistics *statm = &ctlr->statistics;
struct spi_statistics *stats = &msg->spi->statistics; struct spi_statistics *stats = &msg->spi->statistics;
@ -1079,28 +1114,9 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
goto out; goto out;
} }
if (ret > 0) { ret = spi_transfer_wait(ctlr, msg, xfer);
ret = 0; if (ret < 0)
ms = 8LL * 1000LL * xfer->len; msg->status = ret;
do_div(ms, xfer->speed_hz);
ms += ms + 200; /* some tolerance */
if (ms > UINT_MAX)
ms = UINT_MAX;
ms = wait_for_completion_timeout(&ctlr->xfer_completion,
msecs_to_jiffies(ms));
}
if (ms == 0) {
SPI_STATISTICS_INCREMENT_FIELD(statm,
timedout);
SPI_STATISTICS_INCREMENT_FIELD(stats,
timedout);
dev_err(&msg->spi->dev,
"SPI transfer timed out\n");
msg->status = -ETIMEDOUT;
}
} else { } else {
if (xfer->len) if (xfer->len)
dev_err(&msg->spi->dev, dev_err(&msg->spi->dev,