From fdd50409c8b9ce4cdd757ce10bf2e39e9c172de6 Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Tue, 7 Jul 2015 17:34:49 +0300 Subject: [PATCH] gpio: pca953x: fix nested irqs rescheduling MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit pca953x interrupt controller functionality is implemented using nested threaded IRQs which require parent_irq to be configured properly otherwise below warning can be seen if IRQ core will try re-schedule nested IRQ: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 12 at kernel/irq/manage.c:696 irq_nested_primary_handler+0x30/0x38() Primary handler called for nested irq 301 Modules linked in: uinput ipv6 smsc95xx usbnet mii imx2_wdt etnaviv(C) matrix_keypad matrix_keymap ar1021_i2c CPU: 1 PID: 12 Comm: ksoftirqd/1 Tainted: G WC 4.1.1 #9 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) Backtrace: [] (dump_backtrace) from [] (show_stack+0x20/0x24) [] (show_stack) from [] (dump_stack+0x70/0xc0) [] (dump_stack) from [] (warn_slowpath_common+0x88/0xc0) [] (warn_slowpath_common) from [] (warn_slowpath_fmt+0x40/0x48) [] (warn_slowpath_fmt) from [] (irq_nested_primary_handler+0x30/0x38) [] (irq_nested_primary_handler) from [] (handle_irq_event_percpu+0x70/0x2d0) [] (handle_irq_event_percpu) from [] (handle_irq_event+0x4c/0x6c) [] (handle_irq_event) from [] (handle_simple_irq+0xa4/0xc8) [] (handle_simple_irq) from [] (resend_irqs+0x50/0x7c) [] (resend_irqs) from [] (tasklet_action+0x94/0x140) [] (tasklet_action) from [] (__do_softirq+0xa0/0x3c8) [] (__do_softirq) from [] (run_ksoftirqd+0x38/0x54) [] (run_ksoftirqd) from [] (smpboot_thread_fn+0x1f8/0x2f0) [] (smpboot_thread_fn) from [] (kthread+0xe8/0x104) [] (kthread) from [] (ret_from_fork+0x14/0x2c) ---[ end trace 96052cda48865769 ]--- The issue was reported and described in details by Lothar Waßmann and Christian Gmeiner in https://lkml.org/lkml/2014/9/9/123. Fix it by adding missed call of gpiochip_set_chained_irqchip() so GPIO IRQ chip helpers will set parent_irq for nested IRQs properly. Reported-by: Lothar Waßmann Tested-by: Christian Gmeiner Signed-off-by: Grygorii Strashko Signed-off-by: Linus Walleij --- drivers/gpio/gpio-pca953x.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index d233eb3b8132..50caeb1ee350 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -570,6 +570,10 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, "could not connect irqchip to gpiochip\n"); return ret; } + + gpiochip_set_chained_irqchip(&chip->gpio_chip, + &pca953x_irq_chip, + client->irq, NULL); } return 0; -- 2.30.2