diff options
author | Marc Zyngier <marc.zyngier@arm.com> | 2015-03-18 14:01:22 +0300 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2015-04-09 00:28:28 +0300 |
commit | 1b7047edfcfb257f69e306c9afbab150cb987717 (patch) | |
tree | 68b2383acee6ce6a58900507e797e9c6178e4a5b /include/linux/irq.h | |
parent | fe0c52fc003bc046380e52fe6799c96d770770cc (diff) | |
download | linux-1b7047edfcfb257f69e306c9afbab150cb987717.tar.xz |
genirq: Allow the irqchip state of an IRQ to be save/restored
There is a number of cases where a kernel subsystem may want to
introspect the state of an interrupt at the irqchip level:
- When a peripheral is shared between virtual machines,
its interrupt state becomes part of the guest's state,
and must be switched accordingly. KVM on arm/arm64 requires
this for its guest-visible timer
- Some GPIO controllers seem to require peeking into the
interrupt controller they are connected to to report
their internal state
This seem to be a pattern that is common enough for the core code
to try and support this without too many horrible hacks. Introduce
a pair of accessors (irq_get_irqchip_state/irq_set_irqchip_state)
to retrieve the bits that can be of interest to another subsystem:
pending, active, and masked.
- irq_get_irqchip_state returns the state of the interrupt according
to a parameter set to IRQCHIP_STATE_PENDING, IRQCHIP_STATE_ACTIVE,
IRQCHIP_STATE_MASKED or IRQCHIP_STATE_LINE_LEVEL.
- irq_set_irqchip_state similarly sets the state of the interrupt.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Tested-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Phong Vo <pvo@apm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Tin Huynh <tnhuynh@apm.com>
Cc: Y Vo <yvo@apm.com>
Cc: Toan Le <toanle@apm.com>
Cc: Bjorn Andersson <bjorn@kryo.se>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/1426676484-21812-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/linux/irq.h')
-rw-r--r-- | include/linux/irq.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h index d09ec7a1243e..77dd2e7f93f4 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -30,6 +30,7 @@ struct seq_file; struct module; struct msi_msg; +enum irqchip_irq_state; /* * IRQ line status. @@ -324,6 +325,8 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) * irq_request_resources * @irq_compose_msi_msg: optional to compose message content for MSI * @irq_write_msi_msg: optional to write message content for MSI + * @irq_get_irqchip_state: return the internal state of an interrupt + * @irq_set_irqchip_state: set the internal state of a interrupt * @flags: chip specific flags */ struct irq_chip { @@ -363,6 +366,9 @@ struct irq_chip { void (*irq_compose_msi_msg)(struct irq_data *data, struct msi_msg *msg); void (*irq_write_msi_msg)(struct irq_data *data, struct msi_msg *msg); + int (*irq_get_irqchip_state)(struct irq_data *data, enum irqchip_irq_state which, bool *state); + int (*irq_set_irqchip_state)(struct irq_data *data, enum irqchip_irq_state which, bool state); + unsigned long flags; }; |