The patch spi: Deal with slaves that return from transfer_one() unfinished has been applied to the spi tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 810923f3bf06c11022b7bb370dd3130a956a222e Mon Sep 17 00:00:00 2001 From: Lubomir Rintel <lkundrak@xxxxx> Date: Tue, 13 Nov 2018 11:22:24 +0100 Subject: [PATCH] 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. Signed-off-by: Lubomir Rintel <lkundrak@xxxxx> Acked-by: Pavel Machek <pavel@xxxxxx> Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- 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 6ca59406b0b7..498d3b9bf3ae 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1037,6 +1037,42 @@ 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() * @@ -1050,7 +1086,6 @@ 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; @@ -1079,28 +1114,9 @@ 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, -- 2.19.1
