From c18bbac353ffed50be134b0a2a059a2bd540c503 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Fri, 17 Mar 2023 09:42:30 +0100 Subject: [PATCH 1/3] spi: atmel-quadspi: Don't leak clk enable count in pm resume MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The pm resume call is supposed to enable two clocks. If the second enable fails the callback reports failure but doesn't undo the first enable. So call clk_disable() for the first clock when clk_enable() for the second one fails. Fixes: 4a2f83b7f780 ("spi: atmel-quadspi: add runtime pm support") Signed-off-by: Uwe Kleine-König Reviewed-by: Tudor Ambarus Link: https://lore.kernel.org/r/20230317084232.142257-2-u.kleine-koenig@pengutronix.de Signed-off-by: Mark Brown --- drivers/spi/atmel-quadspi.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index f4632cb07495..0c6f80ddea57 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -786,7 +786,11 @@ static int __maybe_unused atmel_qspi_runtime_resume(struct device *dev) if (ret) return ret; - return clk_enable(aq->qspick); + ret = clk_enable(aq->qspick); + if (ret) + clk_disable(aq->pclk); + + return ret; } static const struct dev_pm_ops __maybe_unused atmel_qspi_pm_ops = { From 9448bc1dee65f86c0fe64d9dea8b410af0586886 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Fri, 17 Mar 2023 09:42:31 +0100 Subject: [PATCH 2/3] spi: atmel-quadspi: Free resources even if runtime resume failed in .remove() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit An early error exit in atmel_qspi_remove() doesn't prevent the device unbind. So this results in an spi controller with an unbound parent and unmapped register space (because devm_ioremap_resource() is undone). So using the remaining spi controller probably results in an oops. Instead unregister the controller unconditionally and only skip hardware access and clk disable. Also add a warning about resume failing and return zero unconditionally. The latter has the only effect to suppress a less helpful error message by the spi core. Fixes: 4a2f83b7f780 ("spi: atmel-quadspi: add runtime pm support") Signed-off-by: Uwe Kleine-König Reviewed-by: Tudor Ambarus Link: https://lore.kernel.org/r/20230317084232.142257-3-u.kleine-koenig@pengutronix.de Signed-off-by: Mark Brown --- drivers/spi/atmel-quadspi.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index 0c6f80ddea57..713a4d6700fd 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -706,18 +706,28 @@ static int atmel_qspi_remove(struct platform_device *pdev) struct atmel_qspi *aq = spi_controller_get_devdata(ctrl); int ret; - ret = pm_runtime_resume_and_get(&pdev->dev); - if (ret < 0) - return ret; - spi_unregister_controller(ctrl); - atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR); + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret >= 0) { + atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR); + clk_disable(aq->qspick); + clk_disable(aq->pclk); + } else { + /* + * atmel_qspi_runtime_{suspend,resume} just disable and enable + * the two clks respectively. So after resume failed these are + * off, and we skip hardware access and disabling these clks again. + */ + dev_warn(&pdev->dev, "Failed to resume device on remove\n"); + } + + clk_unprepare(aq->qspick); + clk_unprepare(aq->pclk); pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); - clk_disable_unprepare(aq->qspick); - clk_disable_unprepare(aq->pclk); return 0; } From 4d70dd0a25081bc4e6378d0da4a7c367389df707 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Fri, 17 Mar 2023 09:42:32 +0100 Subject: [PATCH 3/3] spi: atmel-quadspi: Convert to platform remove callback returning void MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is (mostly) ignored and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König Reviewed-by: Tudor Ambarus Link: https://lore.kernel.org/r/20230317084232.142257-4-u.kleine-koenig@pengutronix.de Signed-off-by: Mark Brown --- drivers/spi/atmel-quadspi.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index 713a4d6700fd..3d1252566134 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -700,7 +700,7 @@ static int atmel_qspi_probe(struct platform_device *pdev) return err; } -static int atmel_qspi_remove(struct platform_device *pdev) +static void atmel_qspi_remove(struct platform_device *pdev) { struct spi_controller *ctrl = platform_get_drvdata(pdev); struct atmel_qspi *aq = spi_controller_get_devdata(ctrl); @@ -727,8 +727,6 @@ static int atmel_qspi_remove(struct platform_device *pdev) pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); - - return 0; } static int __maybe_unused atmel_qspi_suspend(struct device *dev) @@ -837,7 +835,7 @@ static struct platform_driver atmel_qspi_driver = { .pm = pm_ptr(&atmel_qspi_pm_ops), }, .probe = atmel_qspi_probe, - .remove = atmel_qspi_remove, + .remove_new = atmel_qspi_remove, }; module_platform_driver(atmel_qspi_driver);