Merge tag 'tty-4.11-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 tty/serial driver patchset for 4.11-rc1.

  Not much here, but a lot of little fixes and individual serial driver
  updates all over the subsystem. Majority are for the sh-sci driver and
  platform (the arch-specific changes have acks from the maintainer).

  The start of the "serial bus" code is here as well, but nothing is
  converted to use it yet. That work is still ongoing, hopefully will
  start to show up across different subsystems for 4.12 (bluetooth is
  one major place that will be used.)

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

* tag 'tty-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (109 commits)
  tty: pl011: Work around QDF2400 E44 stuck BUSY bit
  atmel_serial: Use the fractional divider when possible
  tty: Remove extra include in HVC console tty framework
  serial: exar: Enable MSI support
  serial: exar: Move register defines from uapi header to consumer site
  serial: pci: Remove unused pci_boards entries
  serial: exar: Move Commtech adapters to 8250_exar as well
  serial: exar: Fix feature control register constants
  serial: exar: Fix initialization of EXAR registers for ports > 0
  serial: exar: Fix mapping of port I/O resources
  serial: sh-sci: fix hardware RX trigger level setting
  tty/serial: atmel: ensure state is restored after suspending
  serial: 8250_dw: Avoid "too much work" from bogus rx timeout interrupt
  serdev: ttyport: check whether tty_init_dev() fails
  serial: 8250_pci: make pciserial_detach_ports() static
  ARM: dts: STiH410-b2260: Enable HW flow-control
  ARM: dts: STiH407-family: Use new Pinctrl groups
  ARM: dts: STiH407-pinctrl: Add Pinctrl group for HW flow-control
  ARM: dts: STiH410-b2260: Identify the UART RTS line
  dt-bindings: serial: Update 'uart-has-rtscts' description
  ...

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c
index b8019c4c1d38..2b5d0fac81f0 100644
--- a/drivers/acpi/spcr.c
+++ b/drivers/acpi/spcr.c
@@ -16,6 +16,26 @@
 #include <linux/kernel.h>
 #include <linux/serial_core.h>
 
+/*
+ * Some Qualcomm Datacenter Technologies SoCs have a defective UART BUSY bit.
+ * Detect them by examining the OEM fields in the SPCR header, similiar to PCI
+ * quirk detection in pci_mcfg.c.
+ */
+static bool qdf2400_erratum_44_present(struct acpi_table_header *h)
+{
+	if (memcmp(h->oem_id, "QCOM  ", ACPI_OEM_ID_SIZE))
+		return false;
+
+	if (!memcmp(h->oem_table_id, "QDF2432 ", ACPI_OEM_TABLE_ID_SIZE))
+		return true;
+
+	if (!memcmp(h->oem_table_id, "QDF2400 ", ACPI_OEM_TABLE_ID_SIZE) &&
+			h->oem_revision == 0)
+		return true;
+
+	return false;
+}
+
 /**
  * parse_spcr() - parse ACPI SPCR table and add preferred console
  *
@@ -93,6 +113,9 @@ int __init parse_spcr(bool earlycon)
 		goto done;
 	}
 
+	if (qdf2400_erratum_44_present(&table->header))
+		uart = "qdf2400_e44";
+
 	snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d", uart, iotype,
 		 table->serial_port.address, baud_rate);