From: Lukas Wunner lukas@wunner.de
commit 236924ee531d6251c8d10e9177b7742a60534ed5 upstream.
If the call to devm_spi_register_controller() fails on probe of the Qualcomm Atheros AR934x/QCA95xx SPI driver, the spi_controller struct is erroneously not freed. Fix by switching over to the new devm_spi_alloc_master() helper.
Moreover, the controller's clock is enabled on probe but not disabled if any of the subsequent probe steps fail.
Finally, there's an ordering issue in ar934x_spi_remove() wherein the clock is disabled even though the controller is not yet unregistered. It is unregistered after ar934x_spi_remove() by the devres framework. As long as it is not unregistered, SPI transfers may still be ongoing and disabling the clock may break them. It is not possible to use devm_spi_register_controller() in this case, so move to the non-devm variant.
All of these bugs have existed since the driver was first introduced, so it seems fair to fix them together in a single commit.
Fixes: 047980c582af ("spi: add driver for ar934x spi controller") Signed-off-by: Lukas Wunner lukas@wunner.de Cc: stable@vger.kernel.org # v5.7+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: stable@vger.kernel.org # v5.7+ Cc: Chuanhong Guo gch981213@gmail.com Link: https://lore.kernel.org/r/1d58367d74d55741e0c2730a51a2b65012c8ab33.160728688... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/spi/spi-ar934x.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
--- a/drivers/spi/spi-ar934x.c +++ b/drivers/spi/spi-ar934x.c @@ -176,10 +176,11 @@ static int ar934x_spi_probe(struct platf if (ret) return ret;
- ctlr = spi_alloc_master(&pdev->dev, sizeof(*sp)); + ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*sp)); if (!ctlr) { dev_info(&pdev->dev, "failed to allocate spi controller\n"); - return -ENOMEM; + ret = -ENOMEM; + goto err_clk_disable; }
/* disable flash mapping and expose spi controller registers */ @@ -202,7 +203,13 @@ static int ar934x_spi_probe(struct platf sp->clk_freq = clk_get_rate(clk); sp->ctlr = ctlr;
- return devm_spi_register_controller(&pdev->dev, ctlr); + ret = spi_register_controller(ctlr); + if (!ret) + return 0; + +err_clk_disable: + clk_disable_unprepare(clk); + return ret; }
static int ar934x_spi_remove(struct platform_device *pdev) @@ -213,6 +220,7 @@ static int ar934x_spi_remove(struct plat ctlr = dev_get_drvdata(&pdev->dev); sp = spi_controller_get_devdata(ctlr);
+ spi_unregister_controller(ctlr); clk_disable_unprepare(sp->clk);
return 0;