Merge tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of serial and tty driver updates for 6.15-rc1.
  Include in here are the following:

   - more great tty layer cleanups from Jiri. Someday this will be done,
     but that's not going to be any year soon...

   - kdb debug driver reverts to fix a reported issue

   - lots of .dts binding updates for different devices with serial
     devices

   - lots of tiny updates and tweaks and a few bugfixes for different
     serial drivers.

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

* tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
  tty: serial: fsl_lpuart: Fix unused variable 'sport' build warning
  serial: stm32: do not deassert RS485 RTS GPIO prematurely
  serial: 8250: add driver for NI UARTs
  dt-bindings: serial: snps-dw-apb-uart: document RZ/N1 binding without DMA
  serial: icom: fix code format problems
  serial: sh-sci: Save and restore more registers
  tty: serial: pl011: remove incorrect of_match_ptr annotation
  dt-bindings: serial: snps-dw-apb-uart: Add support for rk3562
  tty: serial: lpuart: only disable CTS instead of overwriting the whole UARTMODIR register
  tty: caif: removed unused function debugfs_tx()
  serial: 8250_dma: terminate correct DMA in tx_dma_flush()
  tty: serial: fsl_lpuart: rename register variables more specifically
  tty: serial: fsl_lpuart: use port struct directly to simply code
  tty: serial: fsl_lpuart: Use u32 and u8 for register variables
  tty: serial: fsl_lpuart: disable transmitter before changing RS485 related registers
  tty: serial: 8250: Add Brainboxes XC devices
  dt-bindings: serial: fsl-lpuart: support i.MX94
  tty: serial: 8250: Add some more device IDs
  dt-bindings: serial: samsung: add exynos7870-uart compatible
  serial: 8250_dw: Comment possible corner cases in serial_out() implementation
  ...

kernel/debug/debug_core.c

@@ -837,10 +837,6 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
 {
 	struct kgdb_state kgdb_var;
 	struct kgdb_state *ks = &kgdb_var;
-	int ret = 0;
-
-	if (arch_kgdb_ops.enable_nmi)
-		arch_kgdb_ops.enable_nmi(0);
 	/*
 	 * Avoid entering the debugger if we were triggered due to an oops
 	 * but panic_timeout indicates the system should automatically
@@ -858,15 +854,11 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
 	ks->linux_regs		= regs;
 
 	if (kgdb_reenter_check(ks))
-		goto out; /* Ouch, double exception ! */
+		return 0; /* Ouch, double exception ! */
 	if (kgdb_info[ks->cpu].enter_kgdb != 0)
-		goto out;
+		return 0;
 
-	ret = kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
-out:
-	if (arch_kgdb_ops.enable_nmi)
-		arch_kgdb_ops.enable_nmi(1);
-	return ret;
+	return kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
 }
 NOKPROBE_SYMBOL(kgdb_handle_exception);
 

kernel/debug/kdb/kdb_main.c

@@ -25,7 +25,6 @@
 #include <linux/smp.h>
 #include <linux/utsname.h>
 #include <linux/vmalloc.h>
-#include <linux/atomic.h>
 #include <linux/moduleparam.h>
 #include <linux/mm.h>
 #include <linux/init.h>
@@ -2087,32 +2086,6 @@ static int kdb_dmesg(int argc, const char **argv)
 	return 0;
 }
 #endif /* CONFIG_PRINTK */
-
-/* Make sure we balance enable/disable calls, must disable first. */
-static atomic_t kdb_nmi_disabled;
-
-static int kdb_disable_nmi(int argc, const char *argv[])
-{
-	if (atomic_read(&kdb_nmi_disabled))
-		return 0;
-	atomic_set(&kdb_nmi_disabled, 1);
-	arch_kgdb_ops.enable_nmi(0);
-	return 0;
-}
-
-static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
-{
-	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
-		return -EINVAL;
-	arch_kgdb_ops.enable_nmi(1);
-	return 0;
-}
-
-static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
-	.set = kdb_param_enable_nmi,
-};
-module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
-
 /*
  * kdb_cpu - This function implements the 'cpu' command.
  *	cpu	[<cpunum>]
@@ -2804,20 +2777,10 @@ static kdbtab_t maintab[] = {
 	},
 };
 
-static kdbtab_t nmicmd = {
-	.name = "disable_nmi",
-	.func = kdb_disable_nmi,
-	.usage = "",
-	.help = "Disable NMI entry to KDB",
-	.flags = KDB_ENABLE_ALWAYS_SAFE,
-};
-
 /* Initialize the kdb command table. */
 static void __init kdb_inittab(void)
 {
 	kdb_register_table(maintab, ARRAY_SIZE(maintab));
-	if (arch_kgdb_ops.enable_nmi)
-		kdb_register_table(&nmicmd, 1);
 }
 
 /* Execute any commands defined in kdb_cmds.  */