From mboxrd@z Thu Jan 1 00:00:00 1970 From: gregkh@linuxfoundation.org (gregkh at linuxfoundation.org) Date: Sun, 17 Jun 2018 13:23:51 +0200 Subject: Patch "spi: bcm2835aux: ensure interrupts are enabled for shared handler" has been added to the 4.16-stable tree Message-ID: <152923463112765@kroah.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This is a note to let you know that I've just added the patch titled spi: bcm2835aux: ensure interrupts are enabled for shared handler to the 4.16-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-bcm2835aux-ensure-interrupts-are-enabled-for-shared-handler.patch and it can be found in the queue-4.16 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo at baz Sun Jun 17 12:07:34 CEST 2018 From: Rob Herring Date: Thu, 3 May 2018 13:09:44 -0500 Subject: spi: bcm2835aux: ensure interrupts are enabled for shared handler From: Rob Herring [ Upstream commit bc519d9574618e47a0c788000fb78da95e18d953 ] The BCM2835 AUX SPI has a shared interrupt line (with AUX UART). Downstream fixes this with an AUX irqchip to demux the IRQ sources and a DT change which breaks compatibility with older kernels. The AUX irqchip was already rejected for upstream[1] and the DT change would break working systems if the DTB is updated to a newer one. The latter issue was brought to my attention by Alex Graf. The root cause however is a bug in the shared handler. Shared handlers must check that interrupts are actually enabled before servicing the interrupt. Add a check that the TXEMPTY or IDLE interrupts are enabled. [1] https://patchwork.kernel.org/patch/9781221/ Cc: Alexander Graf Cc: Marc Zyngier Cc: Mark Brown Cc: Eric Anholt Cc: Stefan Wahren Cc: Florian Fainelli Cc: Ray Jui Cc: Scott Branden Cc: bcm-kernel-feedback-list at broadcom.com Cc: linux-spi at vger.kernel.org Cc: linux-rpi-kernel at lists.infradead.org Cc: linux-arm-kernel at lists.infradead.org Signed-off-by: Rob Herring Reviewed-by: Eric Anholt Signed-off-by: Mark Brown Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-bcm2835aux.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -184,6 +184,11 @@ static irqreturn_t bcm2835aux_spi_interr struct bcm2835aux_spi *bs = spi_master_get_devdata(master); irqreturn_t ret = IRQ_NONE; + /* IRQ may be shared, so return if our interrupts are disabled */ + if (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_CNTL1) & + (BCM2835_AUX_SPI_CNTL1_TXEMPTY | BCM2835_AUX_SPI_CNTL1_IDLE))) + return ret; + /* check if we have data to read */ while (bs->rx_len && (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & Patches currently in stable-queue which might be from robh at kernel.org are queue-4.16/sh-switch-to-no_bootmem.patch queue-4.16/spi-bcm2835aux-ensure-interrupts-are-enabled-for-shared-handler.patch queue-4.16/dt-bindings-panel-lvds-fix-path-to-display-timing-bindings.patch queue-4.16/dt-bindings-net-ravb-add-support-for-r8a77965-soc.patch queue-4.16/dt-bindings-pinctrl-sunxi-fix-reference-to-driver.patch queue-4.16/dt-bindings-serial-sh-sci-add-support-for-r8a77965-h-scif.patch queue-4.16/doc-add-vendor-prefix-for-kieback-peter-gmbh.patch queue-4.16/dt-bindings-dmaengine-rcar-dmac-document-r8a77965-support.patch