diff options
| author | David Lechner <dlechner@baylibre.com> | 2023-12-04 18:33:35 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2023-12-06 15:19:36 +0100 |
| commit | 07d33c2810bb5fe67747d11f76980ed68602e287 (patch) | |
| tree | a6f75bb44fde74a6bc428538e6e78ca28f5b8d63 /drivers/spi/spi-axi-spi-engine.c | |
| parent | spi: axi-spi-engine: remove delay from CS assertion (diff) | |
| download | linux-07d33c2810bb5fe67747d11f76980ed68602e287.tar.xz linux-07d33c2810bb5fe67747d11f76980ed68602e287.zip | |
spi: axi-spi-engine: add watchdog timer
If there is an issue with the AXI SPI Engine hardware a scheduled
transfer might never be completed and spi_sync() will block forever.
This due to the uninterruptible wait for completion waiting for the
spi_finalize_current_message() that never comes.
Add a watchdog timer that will abort a transfer 5 seconds after it has
been started. This will potentially leave the hardware in a broken state
but it allows software to recover and allow to better diagnose the
underlying issue.
Co-developed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-9-063672323fce@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-axi-spi-engine.c')
| -rw-r--r-- | drivers/spi/spi-axi-spi-engine.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c index 78221715ba81..58280dd1c901 100644 --- a/drivers/spi/spi-axi-spi-engine.c +++ b/drivers/spi/spi-axi-spi-engine.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/platform_device.h> #include <linux/spi/spi.h> +#include <linux/timer.h> #define SPI_ENGINE_VERSION_MAJOR(x) ((x >> 16) & 0xff) #define SPI_ENGINE_VERSION_MINOR(x) ((x >> 8) & 0xff) @@ -114,6 +115,8 @@ struct spi_engine { void __iomem *base; struct ida sync_ida; + struct timer_list watchdog_timer; + struct spi_controller *controller; unsigned int int_enable; }; @@ -488,9 +491,11 @@ static irqreturn_t spi_engine_irq(int irq, void *devid) struct spi_engine_message_state *st = msg->state; if (completed_id == st->sync_id) { - msg->status = 0; - msg->actual_length = msg->frame_length; - spi_finalize_current_message(host); + if (timer_delete_sync(&spi_engine->watchdog_timer)) { + msg->status = 0; + msg->actual_length = msg->frame_length; + spi_finalize_current_message(host); + } disable_int |= SPI_ENGINE_INT_SYNC; } } @@ -573,6 +578,8 @@ static int spi_engine_transfer_one_message(struct spi_controller *host, unsigned int int_enable = 0; unsigned long flags; + mod_timer(&spi_engine->watchdog_timer, jiffies + msecs_to_jiffies(5000)); + spin_lock_irqsave(&spi_engine->lock, flags); if (spi_engine_write_cmd_fifo(spi_engine, msg)) @@ -596,6 +603,20 @@ static int spi_engine_transfer_one_message(struct spi_controller *host, return 0; } +static void spi_engine_timeout(struct timer_list *timer) +{ + struct spi_engine *spi_engine = from_timer(spi_engine, timer, watchdog_timer); + struct spi_controller *host = spi_engine->controller; + + if (WARN_ON(!host->cur_msg)) + return; + + dev_err(&host->dev, + "Timeout occurred while waiting for transfer to complete. Hardware is probably broken.\n"); + host->cur_msg->status = -ETIMEDOUT; + spi_finalize_current_message(host); +} + static void spi_engine_release_hw(void *p) { struct spi_engine *spi_engine = p; @@ -625,6 +646,8 @@ static int spi_engine_probe(struct platform_device *pdev) spin_lock_init(&spi_engine->lock); ida_init(&spi_engine->sync_ida); + timer_setup(&spi_engine->watchdog_timer, spi_engine_timeout, TIMER_IRQSAFE); + spi_engine->controller = host; spi_engine->clk = devm_clk_get_enabled(&pdev->dev, "s_axi_aclk"); if (IS_ERR(spi_engine->clk)) |