Merge tag 'tty-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver fixes from Greg KH:
 "Here are some small serial driver fixes for 7.1-rc6. Included in here
  are:

   - mips serial driver fixes to resolve some long-standing issues with
     how they interacted with the console. That's the "majority" of the
     changes in this merge request

   - sh-sci driver regression fix

   - 8250 driver regression fixes

   - other small serial driver fixes for reported problems.

  All of these have been in linux-next for over a week with no reported
  issues"

* tag 'tty-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: dz: Enable modular build
  serial: zs: Convert to use a platform device
  serial: dz: Convert to use a platform device
  serial: zs: Switch to using channel reset
  serial: zs: Fix bootconsole handover lockup
  serial: dz: Fix bootconsole handover lockup
  serial: dz: Fix bootconsole message clobbering at chip reset
  serial: 8250_dw: dispatch SysRq character in dw8250_handle_irq()
  serial: 8250: dispatch SysRq character in serial8250_handle_irq()
  serial: core: introduce guard(uart_port_lock_check_sysrq_irqsave)
  tty: serial: samsung: Remove redundant port lock acquisition in rx helpers
  serial: altera_jtaguart: handle uart_add_one_port() failures
  serial: qcom_geni: fix kfifo underflow when flush precedes DMA completion IRQ
  serial: fsl_lpuart: fix rx buffer and DMA map leaks in start_rx_dma
  tty: add missing tty_driver include to tty_port.h
  serial: qcom-geni: fix UART_RX_PAR_EN bit position
  serial: sh-sci: fix memory region release in error path
  tty: serial: pch_uart: add check for dma_alloc_coherent()
  serial: zs: Fix swapped RI/DSR modem line transition counting

2 files changed, 13 insertions, 1 deletions

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 666430b47899..110ad4e2aef9 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -1275,6 +1275,18 @@ static inline void uart_unlock_and_check_sysrq_irqrestore(struct uart_port *port
 #endif	/* CONFIG_MAGIC_SYSRQ_SERIAL */
 
 /*
+ * Variant of guard(uart_port_lock_irqsave) for IRQ handlers that may capture
+ * a SysRq character via uart_prepare_sysrq_char(). The destructor uses the
+ * sysrq-aware unlock helper so that a captured port->sysrq_ch is dispatched
+ * to handle_sysrq() on scope exit. The plain guard variant silently drops
+ * sysrq_ch and must not be used by callers that process RX.
+ */
+DEFINE_LOCK_GUARD_1(uart_port_lock_check_sysrq_irqsave, struct uart_port,
+                    uart_port_lock_irqsave(_T->lock, &_T->flags),
+                    uart_unlock_and_check_sysrq_irqrestore(_T->lock, _T->flags),
+                    unsigned long flags);
+
+/*
  * We do the SysRQ and SAK checking like this...
  */
 static inline int uart_handle_break(struct uart_port *port)
diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
index d2a7882c0b58..23cad403bb8f 100644
--- a/include/linux/tty_port.h
+++ b/include/linux/tty_port.h
@@ -6,10 +6,10 @@
 #include <linux/kref.h>
 #include <linux/mutex.h>
 #include <linux/tty_buffer.h>
+#include <linux/tty_driver.h>
 #include <linux/wait.h>
 
 struct attribute_group;
-struct tty_driver;
 struct tty_port;
 struct tty_struct;