53 lines
1.9 KiB
Diff
53 lines
1.9 KiB
Diff
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From: John Ogness <john.ogness@linutronix.de>
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Date: Tue, 20 Aug 2024 08:35:36 +0206
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Subject: [PATCH 10/54] serial: core: Provide low-level functions to lock port
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.11/older/patches-6.11-rt7.tar.xz
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It will be necessary at times for the uart nbcon console
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drivers to acquire the port lock directly (without the
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additional nbcon functionality of the port lock wrappers).
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These are special cases such as the implementation of the
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device_lock()/device_unlock() callbacks or for internal
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port lock wrapper synchronization.
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Provide low-level variants __uart_port_lock_irqsave() and
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__uart_port_unlock_irqrestore() for this purpose.
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Signed-off-by: John Ogness <john.ogness@linutronix.de>
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Reviewed-by: Petr Mladek <pmladek@suse.com>
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Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Link: https://lore.kernel.org/r/20240820063001.36405-11-john.ogness@linutronix.de
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Signed-off-by: Petr Mladek <pmladek@suse.com>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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include/linux/serial_core.h | 18 ++++++++++++++++++
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1 file changed, 18 insertions(+)
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--- a/include/linux/serial_core.h
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+++ b/include/linux/serial_core.h
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@@ -590,6 +590,24 @@ struct uart_port {
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void *private_data; /* generic platform data pointer */
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};
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+/*
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+ * Only for console->device_lock()/_unlock() callbacks and internal
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+ * port lock wrapper synchronization.
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+ */
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+static inline void __uart_port_lock_irqsave(struct uart_port *up, unsigned long *flags)
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+{
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+ spin_lock_irqsave(&up->lock, *flags);
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+}
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+
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+/*
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+ * Only for console->device_lock()/_unlock() callbacks and internal
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+ * port lock wrapper synchronization.
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+ */
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+static inline void __uart_port_unlock_irqrestore(struct uart_port *up, unsigned long flags)
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+{
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+ spin_unlock_irqrestore(&up->lock, flags);
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+}
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+
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/**
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* uart_port_lock - Lock the UART port
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* @up: Pointer to UART port structure
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