The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3d87b613d6a3c6f0980e877ab0895785a2dde581 Mon Sep 17 00:00:00 2001

From: Krzysztof Kozlowski krzk@kernel.org Date: Mon, 22 Jun 2020 13:05:42 +0200 Subject: [PATCH] spi: spi-fsl-dspi: Fix external abort on interrupt in resume or exit paths

If shared interrupt comes late, during probe error path or device remove (could be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler dspi_interrupt() will access registers with the clock being disabled. This leads to external abort on non-linefetch on Toradex Colibri VF50 module (with Vybrid VF5xx):

$ echo 4002d000.spi > /sys/devices/platform/soc/40000000.bus/4002d000.spi/driver/unbind

Unhandled fault: external abort on non-linefetch (0x1008) at 0x8887f02c Internal error: : 1008 [#1] ARM Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) Backtrace: (regmap_mmio_read32le) (regmap_mmio_read) (_regmap_bus_reg_read) (_regmap_read) (regmap_read) (dspi_interrupt) (free_irq) (devm_irq_release) (release_nodes) (devres_release_all) (device_release_driver_internal)

The resource-managed framework should not be used for shared interrupt handling, because the interrupt handler might be called after releasing other resources and disabling clocks.

Similar bug could happen during suspend - the shared interrupt handler could be invoked after suspending the device. Each device sharing this interrupt line should disable the IRQ during suspend so handler will be invoked only in following cases: 1. None suspended, 2. All devices resumed.

Fixes: 349ad66c0ab0 ("spi:Add Freescale DSPI driver for Vybrid VF610 platform") Signed-off-by: Krzysztof Kozlowski krzk@kernel.org Tested-by: Vladimir Oltean vladimir.oltean@nxp.com Reviewed-by: Vladimir Oltean vladimir.oltean@nxp.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200622110543.5035-3-krzk@kernel.org Signed-off-by: Mark Brown broonie@kernel.org

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index ec7919d9c0d9..e0b30e4b1b69 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -1109,6 +1109,8 @@ static int dspi_suspend(struct device *dev) struct spi_controller *ctlr = dev_get_drvdata(dev); struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);

+ if (dspi->irq) + disable_irq(dspi->irq); spi_controller_suspend(ctlr); clk_disable_unprepare(dspi->clk);

@@ -1129,6 +1131,8 @@ static int dspi_resume(struct device *dev) if (ret) return ret; spi_controller_resume(ctlr); + if (dspi->irq) + enable_irq(dspi->irq);

return 0; } @@ -1385,8 +1389,8 @@ static int dspi_probe(struct platform_device *pdev) goto poll_mode; }

- ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, - IRQF_SHARED, pdev->name, dspi); + ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL, + IRQF_SHARED, pdev->name, dspi); if (ret < 0) { dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n"); goto out_clk_put; @@ -1400,7 +1404,7 @@ poll_mode: ret = dspi_request_dma(dspi, res->start); if (ret < 0) { dev_err(&pdev->dev, "can't get dma channels\n"); - goto out_clk_put; + goto out_free_irq; } }

@@ -1415,11 +1419,14 @@ poll_mode: ret = spi_register_controller(ctlr); if (ret != 0) { dev_err(&pdev->dev, "Problem registering DSPI ctlr\n"); - goto out_clk_put; + goto out_free_irq; }

return ret;

+out_free_irq: + if (dspi->irq) + free_irq(dspi->irq, dspi); out_clk_put: clk_disable_unprepare(dspi->clk); out_ctlr_put: @@ -1445,6 +1452,8 @@ static int dspi_remove(struct platform_device *pdev) regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);

dspi_release_dma(dspi); + if (dspi->irq) + free_irq(dspi->irq, dspi); clk_disable_unprepare(dspi->clk);

return 0;