Merge tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty and serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver updates for 5.19-rc1.

  Lots of tiny cleanups in here, the major stuff is:

   - termbit cleanups and unification by Ilpo. A much needed change that
     goes a long way to making things simpler for all of the different
     arches

   - tty documentation cleanups and movements to their own place in the
     documentation tree

   - old tty driver cleanups and fixes from Jiri to bring some existing
     drivers into the modern world

   - RS485 cleanups and unifications to make it easier for individual
     drivers to support this mode instead of having to duplicate logic
     in each driver

   - Lots of 8250 driver updates and additions

   - new device id additions

   - n_gsm continued fixes and cleanups

   - other minor serial driver updates and cleanups

  All of these have been in linux-next for weeks with no reported issues"

* tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (166 commits)
  tty: Rework receive flow control char logic
  pcmcia: synclink_cs: Don't allow CS5-6
  serial: stm32-usart: Correct CSIZE, bits, and parity
  serial: st-asc: Sanitize CSIZE and correct PARENB for CS7
  serial: sifive: Sanitize CSIZE and c_iflag
  serial: sh-sci: Don't allow CS5-6
  serial: txx9: Don't allow CS5-6
  serial: rda-uart: Don't allow CS5-6
  serial: digicolor-usart: Don't allow CS5-6
  serial: uartlite: Fix BRKINT clearing
  serial: cpm_uart: Fix build error without CONFIG_SERIAL_CPM_CONSOLE
  serial: core: Do stop_rx in suspend path for console if console_suspend is disabled
  tty: serial: qcom-geni-serial: Remove uart frequency table. Instead, find suitable frequency with call to clk_round_rate.
  dt-bindings: serial: renesas,em-uart: Add RZ/V2M clock to access the registers
  serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485
  Revert "serial: 8250_mtk: Make sure to select the right FEATURE_SEL"
  serial: msm_serial: disable interrupts in __msm_console_write()
  serial: meson: acquire port->lock in startup()
  serial: 8250_dw: Use dev_err_probe()
  serial: 8250_dw: Use devm_add_action_or_reset()
  ...

1 files changed, 15 insertions, 12 deletions

diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 2884cd638d64..18e623325887 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -232,8 +232,10 @@ static void showacpu(void *dummy)
 	unsigned long flags;
 
 	/* Idle CPUs have no interesting backtrace. */
-	if (idle_cpu(smp_processor_id()))
+	if (idle_cpu(smp_processor_id())) {
+		pr_info("CPU%d: backtrace skipped as idling\n", smp_processor_id());
 		return;
+	}
 
 	raw_spin_lock_irqsave(&show_lock, flags);
 	pr_info("CPU%d:\n", smp_processor_id());
@@ -260,10 +262,13 @@ static void sysrq_handle_showallcpus(int key)
 
 		if (in_hardirq())
 			regs = get_irq_regs();
-		if (regs) {
-			pr_info("CPU%d:\n", smp_processor_id());
+
+		pr_info("CPU%d:\n", smp_processor_id());
+		if (regs)
 			show_regs(regs);
-		}
+		else
+			show_stack(NULL, NULL, KERN_INFO);
+
 		schedule_work(&sysrq_showallcpus);
 	}
 }
@@ -274,6 +279,8 @@ static const struct sysrq_key_op sysrq_showallcpus_op = {
 	.action_msg	= "Show backtrace of all active CPUs",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
+#else
+#define sysrq_showallcpus_op (*(const struct sysrq_key_op *)NULL)
 #endif
 
 static void sysrq_handle_showregs(int key)
@@ -405,6 +412,7 @@ static const struct sysrq_key_op sysrq_moom_op = {
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
 
+#ifdef CONFIG_BLOCK
 static void sysrq_handle_thaw(int key)
 {
 	emergency_thaw_all();
@@ -415,6 +423,9 @@ static const struct sysrq_key_op sysrq_thaw_op = {
 	.action_msg	= "Emergency Thaw of all frozen filesystems",
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
+#else
+#define sysrq_thaw_op (*(const struct sysrq_key_op *)NULL)
+#endif
 
 static void sysrq_handle_kill(int key)
 {
@@ -468,17 +479,9 @@ static const struct sysrq_key_op *sysrq_key_table[62] = {
 	NULL,				/* g */
 	NULL,				/* h - reserved for help */
 	&sysrq_kill_op,			/* i */
-#ifdef CONFIG_BLOCK
 	&sysrq_thaw_op,			/* j */
-#else
-	NULL,				/* j */
-#endif
 	&sysrq_SAK_op,			/* k */
-#ifdef CONFIG_SMP
 	&sysrq_showallcpus_op,		/* l */
-#else
-	NULL,				/* l */
-#endif
 	&sysrq_showmem_op,		/* m */
 	&sysrq_unrt_op,			/* n */
 	/* o: This will often be registered as 'Off' at init time */