forked from Minki/linux
109fdf1572
When running -rt kernel and an interrupt happens on a GPIO line controlled by Intel Cherryview/Braswell pinctrl driver we get: BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 Preemption disabled at:[<ffffffff81092e9f>] cpu_startup_entry+0x17f/0x480 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.5-rt5 #16 ... Call Trace: <IRQ> [<ffffffff816283c6>] dump_stack+0x4a/0x61 [<ffffffff81077e17>] ___might_sleep+0xe7/0x170 [<ffffffff8162d6cf>] rt_spin_lock+0x1f/0x50 [<ffffffff812e52ed>] chv_gpio_irq_ack+0x3d/0xa0 [<ffffffff810a72f5>] handle_edge_irq+0x75/0x180 [<ffffffff810a3457>] generic_handle_irq+0x27/0x40 [<ffffffff812e57de>] chv_gpio_irq_handler+0x7e/0x110 [<ffffffff810050aa>] handle_irq+0xaa/0x190 ... This is because desc->lock is raw_spinlock and is held when chv_gpio_irq_ack() is called by the genirq core. chv_gpio_irq_ack() in turn takes pctrl->lock which in -rt is an rt-mutex causing might_sleep() rightfully to complain about sleeping function called from invalid context. In order to keep -rt happy but at the same time make sure that register accesses get serialized, convert the driver to use raw_spinlock instead. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| pinctrl-baytrail.c | ||
| pinctrl-cherryview.c | ||
| pinctrl-intel.c | ||
| pinctrl-intel.h | ||
| pinctrl-sunrisepoint.c | ||