Merge tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the large set of char/misc/whatever driver subsystem updates
  for 5.12-rc1. Over time it seems like this tree is collecting more and
  more tiny driver subsystems in one place, making it easier for those
  maintainers, which is why this is getting larger.

  Included in here are:

   - coresight driver updates

   - habannalabs driver updates

   - virtual acrn driver addition (proper acks from the x86 maintainers)

   - broadcom misc driver addition

   - speakup driver updates

   - soundwire driver updates

   - fpga driver updates

   - amba driver updates

   - mei driver updates

   - vfio driver updates

   - greybus driver updates

   - nvmeem driver updates

   - phy driver updates

   - mhi driver updates

   - interconnect driver udpates

   - fsl-mc bus driver updates

   - random driver fix

   - some small misc driver updates (rtsx, pvpanic, etc.)

  All of these have been in linux-next for a while, with the only
  reported issue being a merge conflict due to the dfl_device_id
  addition from the fpga subsystem in here"

* tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits)
  spmi: spmi-pmic-arb: Fix hw_irq overflow
  Documentation: coresight: Add PID tracing description
  coresight: etm-perf: Support PID tracing for kernel at EL2
  coresight: etm-perf: Clarify comment on perf options
  ACRN: update MAINTAINERS: mailing list is subscribers-only
  regmap: sdw-mbq: use MODULE_LICENSE("GPL")
  regmap: sdw: use no_pm routines for SoundWire 1.2 MBQ
  regmap: sdw: use _no_pm functions in regmap_read/write
  soundwire: intel: fix possible crash when no device is detected
  MAINTAINERS: replace my with email with replacements
  mhi: Fix double dma free
  uapi: map_to_7segment: Update example in documentation
  uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED
  drivers/misc/vmw_vmci: restrict too big queue size in qp_host_alloc_queue
  firewire: replace tricky statement by two simple ones
  vme: make remove callback return void
  firmware: google: make coreboot driver's remove callback return void
  firmware: xilinx: Use explicit values for all enum values
  sample/acrn: Introduce a sample of HSM ioctl interface usage
  virt: acrn: Introduce an interface for Service VM to control vCPU
  ...

17 files changed, 140 insertions, 151 deletions

diff --git a/drivers/accessibility/speakup/serialio.c b/drivers/accessibility/speakup/serialio.c
index 403b01d66367..53580bdc5baa 100644
--- a/drivers/accessibility/speakup/serialio.c
+++ b/drivers/accessibility/speakup/serialio.c
@@ -27,11 +27,11 @@ static const struct old_serial_port *serstate;
 static int timeouts;
 
 static int spk_serial_out(struct spk_synth *in_synth, const char ch);
-static void spk_serial_send_xchar(char ch);
-static void spk_serial_tiocmset(unsigned int set, unsigned int clear);
-static unsigned char spk_serial_in(void);
-static unsigned char spk_serial_in_nowait(void);
-static void spk_serial_flush_buffer(void);
+static void spk_serial_send_xchar(struct spk_synth *in_synth, char ch);
+static void spk_serial_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear);
+static unsigned char spk_serial_in(struct spk_synth *in_synth);
+static unsigned char spk_serial_in_nowait(struct spk_synth *in_synth);
+static void spk_serial_flush_buffer(struct spk_synth *in_synth);
 static int spk_serial_wait_for_xmitr(struct spk_synth *in_synth);
 
 struct spk_io_ops spk_serial_io_ops = {
@@ -150,7 +150,7 @@ static void start_serial_interrupt(int irq)
 	outb(1, speakup_info.port_tts + UART_FCR);	/* Turn FIFO On */
 }
 
-static void spk_serial_send_xchar(char ch)
+static void spk_serial_send_xchar(struct spk_synth *synth, char ch)
 {
 	int timeout = SPK_XMITR_TIMEOUT;
 
@@ -162,7 +162,7 @@ static void spk_serial_send_xchar(char ch)
 	outb(ch, speakup_info.port_tts);
 }
 
-static void spk_serial_tiocmset(unsigned int set, unsigned int clear)
+static void spk_serial_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear)
 {
 	int old = inb(speakup_info.port_tts + UART_MCR);
 
@@ -251,7 +251,7 @@ static int spk_serial_wait_for_xmitr(struct spk_synth *in_synth)
 	return 1;
 }
 
-static unsigned char spk_serial_in(void)
+static unsigned char spk_serial_in(struct spk_synth *in_synth)
 {
 	int tmout = SPK_SERIAL_TIMEOUT;
 
@@ -265,7 +265,7 @@ static unsigned char spk_serial_in(void)
 	return inb_p(speakup_info.port_tts + UART_RX);
 }
 
-static unsigned char spk_serial_in_nowait(void)
+static unsigned char spk_serial_in_nowait(struct spk_synth *in_synth)
 {
 	unsigned char lsr;
 
@@ -275,7 +275,7 @@ static unsigned char spk_serial_in_nowait(void)
 	return inb_p(speakup_info.port_tts + UART_RX);
 }
 
-static void spk_serial_flush_buffer(void)
+static void spk_serial_flush_buffer(struct spk_synth *in_synth)
 {
 	/* TODO: flush the UART 16550 buffer */
 }
@@ -307,7 +307,7 @@ const char *spk_serial_synth_immediate(struct spk_synth *synth,
 }
 EXPORT_SYMBOL_GPL(spk_serial_synth_immediate);
 
-void spk_serial_release(void)
+void spk_serial_release(struct spk_synth *synth)
 {
 	spk_stop_serial_interrupt();
 	if (speakup_info.port_tts == 0)
diff --git a/drivers/accessibility/speakup/speakup_acntpc.c b/drivers/accessibility/speakup/speakup_acntpc.c
index c94328a5bd4a..c1ec087dca13 100644
--- a/drivers/accessibility/speakup/speakup_acntpc.c
+++ b/drivers/accessibility/speakup/speakup_acntpc.c
@@ -25,7 +25,7 @@
 #define PROCSPEECH '\r'
 
 static int synth_probe(struct spk_synth *synth);
-static void accent_release(void);
+static void accent_release(struct spk_synth *synth);
 static const char *synth_immediate(struct spk_synth *synth, const char *buf);
 static void do_catch_up(struct spk_synth *synth);
 static void synth_flush(struct spk_synth *synth);
@@ -294,7 +294,7 @@ static int synth_probe(struct spk_synth *synth)
 	return 0;
 }
 
-static void accent_release(void)
+static void accent_release(struct spk_synth *synth)
 {
 	spk_stop_serial_interrupt();
 	if (speakup_info.port_tts)
diff --git a/drivers/accessibility/speakup/speakup_apollo.c b/drivers/accessibility/speakup/speakup_apollo.c
index 0877b4044c28..cd63581b2e99 100644
--- a/drivers/accessibility/speakup/speakup_apollo.c
+++ b/drivers/accessibility/speakup/speakup_apollo.c
@@ -163,8 +163,8 @@ static void do_catch_up(struct spk_synth *synth)
 		full_time_val = full_time->u.n.value;
 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
 		if (!synth->io_ops->synth_out(synth, ch)) {
-			synth->io_ops->tiocmset(0, UART_MCR_RTS);
-			synth->io_ops->tiocmset(UART_MCR_RTS, 0);
+			synth->io_ops->tiocmset(synth, 0, UART_MCR_RTS);
+			synth->io_ops->tiocmset(synth, UART_MCR_RTS, 0);
 			schedule_timeout(msecs_to_jiffies(full_time_val));
 			continue;
 		}
diff --git a/drivers/accessibility/speakup/speakup_audptr.c b/drivers/accessibility/speakup/speakup_audptr.c
index e6a6a9665d8f..e89fd72579e6 100644
--- a/drivers/accessibility/speakup/speakup_audptr.c
+++ b/drivers/accessibility/speakup/speakup_audptr.c
@@ -119,8 +119,8 @@ static struct spk_synth synth_audptr = {
 
 static void synth_flush(struct spk_synth *synth)
 {
-	synth->io_ops->flush_buffer();
-	synth->io_ops->send_xchar(SYNTH_CLEAR);
+	synth->io_ops->flush_buffer(synth);
+	synth->io_ops->send_xchar(synth, SYNTH_CLEAR);
 	synth->io_ops->synth_out(synth, PROCSPEECH);
 }
 
@@ -130,11 +130,11 @@ static void synth_version(struct spk_synth *synth)
 	char synth_id[40] = "";
 
 	synth->synth_immediate(synth, "\x05[Q]");
-	synth_id[test] = synth->io_ops->synth_in();
+	synth_id[test] = synth->io_ops->synth_in(synth);
 	if (synth_id[test] == 'A') {
 		do {
 			/* read version string from synth */
-			synth_id[++test] = synth->io_ops->synth_in();
+			synth_id[++test] = synth->io_ops->synth_in(synth);
 		} while (synth_id[test] != '\n' && test < 32);
 		synth_id[++test] = 0x00;
 	}
diff --git a/drivers/accessibility/speakup/speakup_decext.c b/drivers/accessibility/speakup/speakup_decext.c
index 7408eb29cf38..092cfd08a9e1 100644
--- a/drivers/accessibility/speakup/speakup_decext.c
+++ b/drivers/accessibility/speakup/speakup_decext.c
@@ -218,7 +218,7 @@ static void do_catch_up(struct spk_synth *synth)
 static void synth_flush(struct spk_synth *synth)
 {
 	in_escape = 0;
-	synth->io_ops->flush_buffer();
+	synth->io_ops->flush_buffer(synth);
 	synth->synth_immediate(synth, "\033P;10z\033\\");
 }
 
diff --git a/drivers/accessibility/speakup/speakup_decpc.c b/drivers/accessibility/speakup/speakup_decpc.c
index 96f24c848cc5..dec314dee214 100644
--- a/drivers/accessibility/speakup/speakup_decpc.c
+++ b/drivers/accessibility/speakup/speakup_decpc.c
@@ -125,7 +125,7 @@ enum {	PRIMARY_DIC	= 0, USER_DIC, COMMAND_DIC, ABBREV_DIC };
 #define SYNTH_IO_EXTENT 8
 
 static int synth_probe(struct spk_synth *synth);
-static void dtpc_release(void);
+static void dtpc_release(struct spk_synth *synth);
 static const char *synth_immediate(struct spk_synth *synth, const char *buf);
 static void do_catch_up(struct spk_synth *synth);
 static void synth_flush(struct spk_synth *synth);
@@ -474,7 +474,7 @@ static int synth_probe(struct spk_synth *synth)
 	return 0;
 }
 
-static void dtpc_release(void)
+static void dtpc_release(struct spk_synth *synth)
 {
 	spk_stop_serial_interrupt();
 	if (speakup_info.port_tts)
diff --git a/drivers/accessibility/speakup/speakup_dectlk.c b/drivers/accessibility/speakup/speakup_dectlk.c
index ab6d61e80b1c..580ec796816b 100644
--- a/drivers/accessibility/speakup/speakup_dectlk.c
+++ b/drivers/accessibility/speakup/speakup_dectlk.c
@@ -78,6 +78,8 @@ static struct kobj_attribute direct_attribute =
 	__ATTR(direct, 0644, spk_var_show, spk_var_store);
 static struct kobj_attribute full_time_attribute =
 	__ATTR(full_time, 0644, spk_var_show, spk_var_store);
+static struct kobj_attribute flush_time_attribute =
+	__ATTR(flush_time, 0644, spk_var_show, spk_var_store);
 static struct kobj_attribute jiffy_delta_attribute =
 	__ATTR(jiffy_delta, 0644, spk_var_show, spk_var_store);
 static struct kobj_attribute trigger_time_attribute =
@@ -99,6 +101,7 @@ static struct attribute *synth_attrs[] = {
 	&delay_time_attribute.attr,
 	&direct_attribute.attr,
 	&full_time_attribute.attr,
+	&flush_time_attribute.attr,
 	&jiffy_delta_attribute.attr,
 	&trigger_time_attribute.attr,
 	NULL,	/* need to NULL terminate the list of attributes */
@@ -118,6 +121,7 @@ static struct spk_synth synth_dectlk = {
 	.trigger = 50,
 	.jiffies = 50,
 	.full = 40000,
+	.flush_time = 4000,
 	.dev_name = SYNTH_DEFAULT_DEV,
 	.startup = SYNTH_START,
 	.checkval = SYNTH_CHECK,
@@ -200,18 +204,23 @@ static void do_catch_up(struct spk_synth *synth)
 	static u_char last = '\0';
 	unsigned long flags;
 	unsigned long jiff_max;
-	unsigned long timeout = msecs_to_jiffies(4000);
+	unsigned long timeout;
 	DEFINE_WAIT(wait);
 	struct var_t *jiffy_delta;
 	struct var_t *delay_time;
+	struct var_t *flush_time;
 	int jiffy_delta_val;
 	int delay_time_val;
+	int timeout_val;
 
 	jiffy_delta = spk_get_var(JIFFY);
 	delay_time = spk_get_var(DELAY);
+	flush_time = spk_get_var(FLUSH);
 	spin_lock_irqsave(&speakup_info.spinlock, flags);
 	jiffy_delta_val = jiffy_delta->u.n.value;
+	timeout_val = flush_time->u.n.value;
 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
+	timeout = msecs_to_jiffies(timeout_val);
 	jiff_max = jiffies + jiffy_delta_val;
 
 	while (!kthread_should_stop()) {
@@ -289,7 +298,7 @@ static void synth_flush(struct spk_synth *synth)
 		synth->io_ops->synth_out(synth, ']');
 	in_escape = 0;
 	is_flushing = 1;
-	synth->io_ops->flush_buffer();
+	synth->io_ops->flush_buffer(synth);
 	synth->io_ops->synth_out(synth, SYNTH_CLEAR);
 }
 
diff --git a/drivers/accessibility/speakup/speakup_dtlk.c b/drivers/accessibility/speakup/speakup_dtlk.c
index dbebed0eeeec..92838d3ae9eb 100644
--- a/drivers/accessibility/speakup/speakup_dtlk.c
+++ b/drivers/accessibility/speakup/speakup_dtlk.c
@@ -24,7 +24,7 @@
 #define PROCSPEECH 0x00
 
 static int synth_probe(struct spk_synth *synth);
-static void dtlk_release(void);
+static void dtlk_release(struct spk_synth *synth);
 static const char *synth_immediate(struct spk_synth *synth, const char *buf);
 static void do_catch_up(struct spk_synth *synth);
 static void synth_flush(struct spk_synth *synth);
@@ -365,7 +365,7 @@ static int synth_probe(struct spk_synth *synth)
 	return 0;
 }
 
-static void dtlk_release(void)
+static void dtlk_release(struct spk_synth *synth)
 {
 	spk_stop_serial_interrupt();
 	if (speakup_info.port_tts)
diff --git a/drivers/accessibility/speakup/speakup_keypc.c b/drivers/accessibility/speakup/speakup_keypc.c
index 414827e888fc..311f4aa0be22 100644
--- a/drivers/accessibility/speakup/speakup_keypc.c
+++ b/drivers/accessibility/speakup/speakup_keypc.c
@@ -24,7 +24,7 @@
 #define SYNTH_CLEAR 0x03
 
 static int synth_probe(struct spk_synth *synth);
-static void keynote_release(void);
+static void keynote_release(struct spk_synth *synth);
 static const char *synth_immediate(struct spk_synth *synth, const char *buf);
 static void do_catch_up(struct spk_synth *synth);
 static void synth_flush(struct spk_synth *synth);
@@ -295,7 +295,7 @@ static int synth_probe(struct spk_synth *synth)
 	return 0;
 }
 
-static void keynote_release(void)
+static void keynote_release(struct spk_synth *synth)
 {
 	spk_stop_serial_interrupt();
 	if (synth_port)
diff --git a/drivers/accessibility/speakup/speakup_ltlk.c b/drivers/accessibility/speakup/speakup_ltlk.c
index 3c59519a871f..3e59b387d0c4 100644
--- a/drivers/accessibility/speakup/speakup_ltlk.c
+++ b/drivers/accessibility/speakup/speakup_ltlk.c
@@ -132,7 +132,7 @@ static void synth_interrogate(struct spk_synth *synth)
 
 	synth->synth_immediate(synth, "\x18\x01?");
 	for (i = 0; i < 50; i++) {
-		buf[i] = synth->io_ops->synth_in();
+		buf[i] = synth->io_ops->synth_in(synth);
 		if (i > 2 && buf[i] == 0x7f)
 			break;
 	}
diff --git a/drivers/accessibility/speakup/speakup_soft.c b/drivers/accessibility/speakup/speakup_soft.c
index 9a7029539f35..c3f97c572fb6 100644
--- a/drivers/accessibility/speakup/speakup_soft.c
+++ b/drivers/accessibility/speakup/speakup_soft.c
@@ -24,7 +24,7 @@
 #define CLEAR_SYNTH 0x18
 
 static int softsynth_probe(struct spk_synth *synth);
-static void softsynth_release(void);
+static void softsynth_release(struct spk_synth *synth);
 static int softsynth_is_alive(struct spk_synth *synth);
 static unsigned char get_index(struct spk_synth *synth);
 
@@ -402,7 +402,7 @@ static int softsynth_probe(struct spk_synth *synth)
 	return 0;
 }
 
-static void softsynth_release(void)
+static void softsynth_release(struct spk_synth *synth)
 {
 	misc_deregister(&synth_device);
 	misc_deregister(&synthu_device);
diff --git a/drivers/accessibility/speakup/speakup_spkout.c b/drivers/accessibility/speakup/speakup_spkout.c
index 6e933bf1de2e..bd3d8dc300ff 100644
--- a/drivers/accessibility/speakup/speakup_spkout.c
+++ b/drivers/accessibility/speakup/speakup_spkout.c
@@ -117,8 +117,8 @@ static struct spk_synth synth_spkout = {
 
 static void synth_flush(struct spk_synth *synth)
 {
-	synth->io_ops->flush_buffer();
-	synth->io_ops->send_xchar(SYNTH_CLEAR);
+	synth->io_ops->flush_buffer(synth);
+	synth->io_ops->send_xchar(synth, SYNTH_CLEAR);
 }
 
 module_param_named(ser, synth_spkout.ser, int, 0444);
diff --git a/drivers/accessibility/speakup/spk_priv.h b/drivers/accessibility/speakup/spk_priv.h
index 0f4bcbe5ddb9..9da57ead17cb 100644
--- a/drivers/accessibility/speakup/spk_priv.h
+++ b/drivers/accessibility/speakup/spk_priv.h
@@ -34,8 +34,8 @@
 
 const struct old_serial_port *spk_serial_init(int index);
 void spk_stop_serial_interrupt(void);
-void spk_serial_release(void);
-void spk_ttyio_release(void);
+void spk_serial_release(struct spk_synth *synth);
+void spk_ttyio_release(struct spk_synth *synth);
 void spk_ttyio_register_ldisc(void);
 void spk_ttyio_unregister_ldisc(void);
 
diff --git a/drivers/accessibility/speakup/spk_ttyio.c b/drivers/accessibility/speakup/spk_ttyio.c
index 835d17455fcd..9af1d4c124d3 100644
--- a/drivers/accessibility/speakup/spk_ttyio.c
+++ b/drivers/accessibility/speakup/spk_ttyio.c
@@ -12,14 +12,15 @@ struct spk_ldisc_data {
 	char buf;
 	struct completion completion;
 	bool buf_free;
+	struct spk_synth *synth;
 };
 
-static struct spk_synth *spk_ttyio_synth;
-static struct tty_struct *speakup_tty;
-/* mutex to protect against speakup_tty disappearing from underneath us while
- * we are using it. this can happen when the device physically unplugged,
- * while in use. it also serialises access to speakup_tty.
+/*
+ * This allows to catch within spk_ttyio_ldisc_open whether it is getting set
+ * on for a speakup-driven device.
  */
+static struct tty_struct *speakup_tty;
+/* This mutex serializes the use of such global speakup_tty variable */
 static DEFINE_MUTEX(speakup_tty_mutex);
 
 static int ser_to_dev(int ser, dev_t *dev_no)
@@ -67,22 +68,20 @@ static int spk_ttyio_ldisc_open(struct tty_struct *tty)
 
 static void spk_ttyio_ldisc_close(struct tty_struct *tty)
 {
-	mutex_lock(&speakup_tty_mutex);
-	kfree(speakup_tty->disc_data);
-	speakup_tty = NULL;
-	mutex_unlock(&speakup_tty_mutex);
+	kfree(tty->disc_data);
 }
 
 static int spk_ttyio_receive_buf2(struct tty_struct *tty,
 				  const unsigned char *cp, char *fp, int count)
 {
 	struct spk_ldisc_data *ldisc_data = tty->disc_data;
+	struct spk_synth *synth = ldisc_data->synth;
 
-	if (spk_ttyio_synth->read_buff_add) {
+	if (synth->read_buff_add) {
 		int i;
 
 		for (i = 0; i < count; i++)
-			spk_ttyio_synth->read_buff_add(cp[i]);
+			synth->read_buff_add(cp[i]);
 
 		return count;
 	}
@@ -114,11 +113,11 @@ static struct tty_ldisc_ops spk_ttyio_ldisc_ops = {
 
 static int spk_ttyio_out(struct spk_synth *in_synth, const char ch);
 static int spk_ttyio_out_unicode(struct spk_synth *in_synth, u16 ch);
-static void spk_ttyio_send_xchar(char ch);
-static void spk_ttyio_tiocmset(unsigned int set, unsigned int clear);
-static unsigned char spk_ttyio_in(void);
-static unsigned char spk_ttyio_in_nowait(void);
-static void spk_ttyio_flush_buffer(void);
+static void spk_ttyio_send_xchar(struct spk_synth *in_synth, char ch);
+static void spk_ttyio_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear);
+static unsigned char spk_ttyio_in(struct spk_synth *in_synth);
+static unsigned char spk_ttyio_in_nowait(struct spk_synth *in_synth);
+static void spk_ttyio_flush_buffer(struct spk_synth *in_synth);
 static int spk_ttyio_wait_for_xmitr(struct spk_synth *in_synth);
 
 struct spk_io_ops spk_ttyio_ops = {
@@ -187,13 +186,17 @@ static int spk_ttyio_initialise_ldisc(struct spk_synth *synth)
 	mutex_lock(&speakup_tty_mutex);
 	speakup_tty = tty;
 	ret = tty_set_ldisc(tty, N_SPEAKUP);
-	if (ret)
-		speakup_tty = NULL;
+	speakup_tty = NULL;
 	mutex_unlock(&speakup_tty_mutex);
 
-	if (!ret)
+	if (!ret) {
 		/* Success */
+		struct spk_ldisc_data *ldisc_data = tty->disc_data;
+
+		ldisc_data->synth = synth;
+		synth->dev = tty;
 		return 0;
+	}
 
 	pr_err("speakup: Failed to set N_SPEAKUP on tty\n");
 
@@ -221,29 +224,30 @@ void spk_ttyio_unregister_ldisc(void)
 
 static int spk_ttyio_out(struct spk_synth *in_synth, const char ch)
 {
-	mutex_lock(&speakup_tty_mutex);
-	if (in_synth->alive && speakup_tty && speakup_tty->ops->write) {
-		int ret = speakup_tty->ops->write(speakup_tty, &ch, 1);
-
-		mutex_unlock(&speakup_tty_mutex);
-		if (ret == 0)
-			/* No room */
-			return 0;
-		if (ret < 0) {
-			pr_warn("%s: I/O error, deactivating speakup\n",
-				in_synth->long_name);
-			/* No synth any more, so nobody will restart TTYs,
-			 * and we thus need to do it ourselves.  Now that there
-			 * is no synth we can let application flood anyway
-			 */
-			in_synth->alive = 0;
-			speakup_start_ttys();
-			return 0;
-		}
+	struct tty_struct *tty = in_synth->dev;
+	int ret;
+
+	if (!in_synth->alive || !tty->ops->write)
+		return 0;
+
+	ret = tty->ops->write(tty, &ch, 1);
+
+	if (ret == 0)
+		/* No room */
+		return 0;
+
+	if (ret > 0)
+		/* Success */
 		return 1;
-	}
 
-	mutex_unlock(&speakup_tty_mutex);
+	pr_warn("%s: I/O error, deactivating speakup\n",
+		in_synth->long_name);
+	/* No synth any more, so nobody will restart TTYs,
+	 * and we thus need to do it ourselves.  Now that there
+	 * is no synth we can let application flood anyway
+	 */
+	in_synth->alive = 0;
+	speakup_start_ttys();
 	return 0;
 }
 
@@ -264,47 +268,20 @@ static int spk_ttyio_out_unicode(struct spk_synth *in_synth, u16 ch)
 	return ret;
 }
 
-static int check_tty(struct tty_struct *tty)
-{
-	if (!tty) {
-		pr_warn("%s: I/O error, deactivating speakup\n",
-			spk_ttyio_synth->long_name);
-		/* No synth any more, so nobody will restart TTYs, and we thus
-		 * need to do it ourselves.  Now that there is no synth we can
-		 * let application flood anyway
-		 */
-		spk_ttyio_synth->alive = 0;
-		speakup_start_ttys();
-		return 1;
-	}
-
-	return 0;
-}
-
-static void spk_ttyio_send_xchar(char ch)
+static void spk_ttyio_send_xchar(struct spk_synth *in_synth, char ch)
 {
-	mutex_lock(&speakup_tty_mutex);
-	if (check_tty(speakup_tty)) {
-		mutex_unlock(&speakup_tty_mutex);
-		return;
-	}
+	struct tty_struct *tty = in_synth->dev;
 
-	if (speakup_tty->ops->send_xchar)
-		speakup_tty->ops->send_xchar(speakup_tty, ch);
-	mutex_unlock(&speakup_tty_mutex);
+	if (tty->ops->send_xchar)
+		tty->ops->send_xchar(tty, ch);
 }
 
-static void spk_ttyio_tiocmset(unsigned int set, unsigned int clear)
+static void spk_ttyio_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear)
 {
-	mutex_lock(&speakup_tty_mutex);
-	if (check_tty(speakup_tty)) {
-		mutex_unlock(&speakup_tty_mutex);
-		return;
-	}
+	struct tty_struct *tty = in_synth->dev;
 
-	if (speakup_tty->ops->tiocmset)
-		speakup_tty->ops->tiocmset(speakup_tty, set, clear);
-	mutex_unlock(&speakup_tty_mutex);
+	if (tty->ops->tiocmset)
+		tty->ops->tiocmset(tty, set, clear);
 }
 
 static int spk_ttyio_wait_for_xmitr(struct spk_synth *in_synth)
@@ -312,9 +289,10 @@ static int spk_ttyio_wait_for_xmitr(struct spk_synth *in_synth)
 	return 1;
 }
 
-static unsigned char ttyio_in(int timeout)
+static unsigned char ttyio_in(struct spk_synth *in_synth, int timeout)
 {
-	struct spk_ldisc_data *ldisc_data = speakup_tty->disc_data;
+	struct tty_struct *tty = in_synth->dev;
+	struct spk_ldisc_data *ldisc_data = tty->disc_data;
 	char rv;
 
 	if (!timeout) {
@@ -334,35 +312,29 @@ static unsigned char ttyio_in(int timeout)
 	mb();
 	ldisc_data->buf_free = true;
 	/* Let TTY push more characters */
-	tty_schedule_flip(speakup_tty->port);
+	tty_schedule_flip(tty->port);
 
 	return rv;
 }
 
-static unsigned char spk_ttyio_in(void)
+static unsigned char spk_ttyio_in(struct spk_synth *in_synth)
 {
-	return ttyio_in(SPK_SYNTH_TIMEOUT);
+	return ttyio_in(in_synth, SPK_SYNTH_TIMEOUT);
 }
 
-static unsigned char spk_ttyio_in_nowait(void)
+static unsigned char spk_ttyio_in_nowait(struct spk_synth *in_synth)
 {
-	u8 rv = ttyio_in(0);
+	u8 rv = ttyio_in(in_synth, 0);
 
 	return (rv == 0xff) ? 0 : rv;
 }
 
-static void spk_ttyio_flush_buffer(void)
+static void spk_ttyio_flush_buffer(struct spk_synth *in_synth)
 {
-	mutex_lock(&speakup_tty_mutex);
-	if (check_tty(speakup_tty)) {
-		mutex_unlock(&speakup_tty_mutex);
-		return;
-	}
+	struct tty_struct *tty = in_synth->dev;
 
-	if (speakup_tty->ops->flush_buffer)
-		speakup_tty->ops->flush_buffer(speakup_tty);
-
-	mutex_unlock(&speakup_tty_mutex);
+	if (tty->ops->flush_buffer)
+		tty->ops->flush_buffer(tty);
 }
 
 int spk_ttyio_synth_probe(struct spk_synth *synth)
@@ -373,37 +345,38 @@ int spk_ttyio_synth_probe(struct spk_synth *synth)
 		return rv;
 
 	synth->alive = 1;
-	spk_ttyio_synth = synth;
 
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spk_ttyio_synth_probe);
 
-void spk_ttyio_release(void)
+void spk_ttyio_release(struct spk_synth *in_synth)
 {
-	if (!speakup_tty)
-		return;
+	struct tty_struct *tty = in_synth->dev;
 
-	tty_lock(speakup_tty);
+	tty_lock(tty);
 
-	if (speakup_tty->ops->close)
-		speakup_tty->ops->close(speakup_tty, NULL);
+	if (tty->ops->close)
+		tty->ops->close(tty, NULL);
+
+	tty_ldisc_flush(tty);
+	tty_unlock(tty);
+	tty_kclose(tty);
 
-	tty_ldisc_flush(speakup_tty);
-	tty_unlock(speakup_tty);
-	tty_kclose(speakup_tty);
+	in_synth->dev = NULL;
 }
 EXPORT_SYMBOL_GPL(spk_ttyio_release);
 
-const char *spk_ttyio_synth_immediate(struct spk_synth *synth, const char *buff)
+const char *spk_ttyio_synth_immediate(struct spk_synth *in_synth, const char *buff)
 {
+	struct tty_struct *tty = in_synth->dev;
 	u_char ch;
 
 	while ((ch = *buff)) {
 		if (ch == '\n')
-			ch = synth->procspeech;
-		if (tty_write_room(speakup_tty) < 1 ||
-		    !synth->io_ops->synth_out(synth, ch))
+			ch = in_synth->procspeech;
+		if (tty_write_room(tty) < 1 ||
+		    !in_synth->io_ops->synth_out(in_synth, ch))
 			return buff;
 		buff++;
 	}
diff --git a/drivers/accessibility/speakup/spk_types.h b/drivers/accessibility/speakup/spk_types.h
index 91fca3033a45..6a96ad94bc3f 100644
--- a/drivers/accessibility/speakup/spk_types.h
+++ b/drivers/accessibility/speakup/spk_types.h
@@ -48,7 +48,7 @@ enum var_id_t {
 	ATTRIB_BLEEP, BLEEPS,
 	RATE, PITCH, VOL, TONE, PUNCT, VOICE, FREQUENCY, LANG,
 	DIRECT, PAUSE,
-	CAPS_START, CAPS_STOP, CHARTAB, INFLECTION,
+	CAPS_START, CAPS_STOP, CHARTAB, INFLECTION, FLUSH,
 	MAXVARS
 };
 
@@ -157,11 +157,11 @@ struct spk_synth;
 struct spk_io_ops {
 	int (*synth_out)(struct spk_synth *synth, const char ch);
 	int (*synth_out_unicode)(struct spk_synth *synth, u16 ch);
-	void (*send_xchar)(char ch);
-	void (*tiocmset)(unsigned int set, unsigned int clear);
-	unsigned char (*synth_in)(void);
-	unsigned char (*synth_in_nowait)(void);
-	void (*flush_buffer)(void);
+	void (*send_xchar)(struct spk_synth *synth, char ch);
+	void (*tiocmset)(struct spk_synth *synth, unsigned int set, unsigned int clear);
+	unsigned char (*synth_in)(struct spk_synth *synth);
+	unsigned char (*synth_in_nowait)(struct spk_synth *synth);
+	void (*flush_buffer)(struct spk_synth *synth);
 	int (*wait_for_xmitr)(struct spk_synth *synth);
 };
 
@@ -178,6 +178,7 @@ struct spk_synth {
 	int trigger;
 	int jiffies;
 	int full;
+	int flush_time;
 	int ser;
 	char *dev_name;
 	short flags;
@@ -188,7 +189,7 @@ struct spk_synth {
 	int *default_vol;
 	struct spk_io_ops *io_ops;
 	int (*probe)(struct spk_synth *synth);
-	void (*release)(void);
+	void (*release)(struct spk_synth *synth);
 	const char *(*synth_immediate)(struct spk_synth *synth,
 				       const char *buff);
 	void (*catch_up)(struct spk_synth *synth);
@@ -200,6 +201,8 @@ struct spk_synth {
 	struct synth_indexing indexing;
 	int alive;
 	struct attribute_group attributes;
+
+	void *dev;
 };
 
 /*
diff --git a/drivers/accessibility/speakup/synth.c b/drivers/accessibility/speakup/synth.c
index ac47dbac7207..2b8699673bac 100644
--- a/drivers/accessibility/speakup/synth.c
+++ b/drivers/accessibility/speakup/synth.c
@@ -137,14 +137,14 @@ EXPORT_SYMBOL_GPL(spk_do_catch_up_unicode);
 
 void spk_synth_flush(struct spk_synth *synth)
 {
-	synth->io_ops->flush_buffer();
+	synth->io_ops->flush_buffer(synth);
 	synth->io_ops->synth_out(synth, synth->clear);
 }
 EXPORT_SYMBOL_GPL(spk_synth_flush);
 
 unsigned char spk_synth_get_index(struct spk_synth *synth)
 {
-	return synth->io_ops->synth_in_nowait();
+	return synth->io_ops->synth_in_nowait(synth);
 }
 EXPORT_SYMBOL_GPL(spk_synth_get_index);
 
@@ -348,6 +348,7 @@ struct var_t synth_time_vars[] = {
 	{ TRIGGER, .u.n = {NULL, 20, 10, 2000, 0, 0, NULL } },
 	{ JIFFY, .u.n = {NULL, 50, 20, 200, 0, 0, NULL } },
 	{ FULL, .u.n = {NULL, 400, 200, 60000, 0, 0, NULL } },
+	{ FLUSH, .u.n = {NULL, 4000, 100, 4000, 0, 0, NULL } },
 	V_LAST_VAR
 };
 
@@ -408,6 +409,8 @@ static int do_synth_init(struct spk_synth *in_synth)
 		synth_time_vars[2].u.n.default_val = synth->jiffies;
 	synth_time_vars[3].u.n.value =
 		synth_time_vars[3].u.n.default_val = synth->full;
+	synth_time_vars[4].u.n.value =
+		synth_time_vars[4].u.n.default_val = synth->flush_time;
 	synth_printf("%s", synth->init);
 	for (var = synth->vars;
 		(var->var_id >= 0) && (var->var_id < MAXVARS); var++)
@@ -440,7 +443,7 @@ void synth_release(void)
 		sysfs_remove_group(speakup_kobj, &synth->attributes);
 	for (var = synth->vars; var->var_id != MAXVARS; var++)
 		speakup_unregister_var(var->var_id);
-	synth->release();
+	synth->release(synth);
 	synth = NULL;
 }
 
diff --git a/drivers/accessibility/speakup/varhandlers.c b/drivers/accessibility/speakup/varhandlers.c
index d7f6bec7ff06..067c0da97dcb 100644
--- a/drivers/accessibility/speakup/varhandlers.c
+++ b/drivers/accessibility/speakup/varhandlers.c
@@ -23,6 +23,7 @@ static struct st_var_header var_headers[] = {
 	{ "trigger_time", TRIGGER, VAR_TIME, NULL, NULL },
 	{ "jiffy_delta", JIFFY, VAR_TIME, NULL, NULL },
 	{ "full_time", FULL, VAR_TIME, NULL, NULL },
+	{ "flush_time", FLUSH, VAR_TIME, NULL, NULL },
 	{ "spell_delay", SPELL_DELAY, VAR_NUM, &spk_spell_delay, NULL },
 	{ "bleeps", BLEEPS, VAR_NUM, &spk_bleeps, NULL },
 	{ "attrib_bleep", ATTRIB_BLEEP, VAR_NUM, &spk_attrib_bleep, NULL },