From da31d8c6af334b3d279e085491d7e2be9b6ed257 Mon Sep 17 00:00:00 2001 From: Lubomir Rintel Date: Tue, 13 Nov 2018 11:22:24 +0100 Subject: [PATCH] UPSTREAM: spi: Deal with slaves that return from transfer_one() unfinished 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. Change-Id: I166415911f30fc821fca73b0250f6350b835e8c0 Signed-off-by: Lubomir Rintel Acked-by: Pavel Machek Reviewed-by: Geert Uytterhoeven Signed-off-by: Mark Brown Signed-off-by: Jon Lin (cherry picked from commit 810923f3bf06c11022b7bb370dd3130a956a222e) --- drivers/spi/spi.c | 62 +++++++++++++++++++++++++++++------------------ 1 file changed, 39 insertions(+), 23 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 6fc5b3de85b9..da10ddd4b6c0 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1039,6 +1039,42 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *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() * @@ -1052,7 +1088,6 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, struct spi_transfer *xfer; bool keep_cs = false; int ret = 0; - unsigned long long ms = 1; struct spi_statistics *statm = &ctlr->statistics; struct spi_statistics *stats = &msg->spi->statistics; @@ -1081,28 +1116,9 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, goto out; } - if (ret > 0) { - ret = 0; - 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"); - msg->status = -ETIMEDOUT; - } + ret = spi_transfer_wait(ctlr, msg, xfer); + if (ret < 0) + msg->status = ret; } else { if (xfer->len) dev_err(&msg->spi->dev,