v4.19.13 snapshot.
diff --git a/drivers/media/dvb-frontends/au8522_common.c b/drivers/media/dvb-frontends/au8522_common.c
new file mode 100644
index 0000000..56605de
--- /dev/null
+++ b/drivers/media/dvb-frontends/au8522_common.c
@@ -0,0 +1,278 @@
+/*
+    Auvitek AU8522 QAM/8VSB demodulator driver
+
+    Copyright (C) 2008 Steven Toth <stoth@linuxtv.org>
+    Copyright (C) 2008 Devin Heitmueller <dheitmueller@linuxtv.org>
+    Copyright (C) 2005-2008 Auvitek International, Ltd.
+    Copyright (C) 2012 Michael Krufky <mkrufky@linuxtv.org>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include <linux/i2c.h>
+#include <media/dvb_frontend.h>
+#include "au8522_priv.h"
+
+static int debug;
+
+#define dprintk(arg...)\
+  do { if (debug)\
+	 printk(arg);\
+  } while (0)
+
+/* Despite the name "hybrid_tuner", the framework works just as well for
+   hybrid demodulators as well... */
+static LIST_HEAD(hybrid_tuner_instance_list);
+static DEFINE_MUTEX(au8522_list_mutex);
+
+/* 16 bit registers, 8 bit values */
+int au8522_writereg(struct au8522_state *state, u16 reg, u8 data)
+{
+	int ret;
+	u8 buf[] = { (reg >> 8) | 0x80, reg & 0xff, data };
+
+	struct i2c_msg msg = { .addr = state->config.demod_address,
+			       .flags = 0, .buf = buf, .len = 3 };
+
+	ret = i2c_transfer(state->i2c, &msg, 1);
+
+	if (ret != 1)
+		printk("%s: writereg error (reg == 0x%02x, val == 0x%04x, ret == %i)\n",
+		       __func__, reg, data, ret);
+
+	return (ret != 1) ? -1 : 0;
+}
+EXPORT_SYMBOL(au8522_writereg);
+
+u8 au8522_readreg(struct au8522_state *state, u16 reg)
+{
+	int ret;
+	u8 b0[] = { (reg >> 8) | 0x40, reg & 0xff };
+	u8 b1[] = { 0 };
+
+	struct i2c_msg msg[] = {
+		{ .addr = state->config.demod_address, .flags = 0,
+		  .buf = b0, .len = 2 },
+		{ .addr = state->config.demod_address, .flags = I2C_M_RD,
+		  .buf = b1, .len = 1 } };
+
+	ret = i2c_transfer(state->i2c, msg, 2);
+
+	if (ret != 2)
+		printk(KERN_ERR "%s: readreg error (ret == %i)\n",
+		       __func__, ret);
+	return b1[0];
+}
+EXPORT_SYMBOL(au8522_readreg);
+
+int au8522_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
+{
+	struct au8522_state *state = fe->demodulator_priv;
+
+	dprintk("%s(%d)\n", __func__, enable);
+
+	if (state->operational_mode == AU8522_ANALOG_MODE) {
+		/* We're being asked to manage the gate even though we're
+		   not in digital mode.  This can occur if we get switched
+		   over to analog mode before the dvb_frontend kernel thread
+		   has completely shutdown */
+		return 0;
+	}
+
+	if (enable)
+		return au8522_writereg(state, 0x106, 1);
+	else
+		return au8522_writereg(state, 0x106, 0);
+}
+EXPORT_SYMBOL(au8522_i2c_gate_ctrl);
+
+int au8522_analog_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
+{
+	struct au8522_state *state = fe->demodulator_priv;
+
+	dprintk("%s(%d)\n", __func__, enable);
+
+	if (enable)
+		return au8522_writereg(state, 0x106, 1);
+	else
+		return au8522_writereg(state, 0x106, 0);
+}
+EXPORT_SYMBOL(au8522_analog_i2c_gate_ctrl);
+
+/* Reset the demod hardware and reset all of the configuration registers
+   to a default state. */
+int au8522_get_state(struct au8522_state **state, struct i2c_adapter *i2c,
+		     u8 client_address)
+{
+	int ret;
+
+	mutex_lock(&au8522_list_mutex);
+	ret = hybrid_tuner_request_state(struct au8522_state, (*state),
+					 hybrid_tuner_instance_list,
+					 i2c, client_address, "au8522");
+	mutex_unlock(&au8522_list_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL(au8522_get_state);
+
+void au8522_release_state(struct au8522_state *state)
+{
+	mutex_lock(&au8522_list_mutex);
+	if (state != NULL)
+		hybrid_tuner_release_state(state);
+	mutex_unlock(&au8522_list_mutex);
+}
+EXPORT_SYMBOL(au8522_release_state);
+
+static int au8522_led_gpio_enable(struct au8522_state *state, int onoff)
+{
+	struct au8522_led_config *led_config = state->config.led_cfg;
+	u8 val;
+
+	/* bail out if we can't control an LED */
+	if (!led_config || !led_config->gpio_output ||
+	    !led_config->gpio_output_enable || !led_config->gpio_output_disable)
+		return 0;
+
+	val = au8522_readreg(state, 0x4000 |
+			     (led_config->gpio_output & ~0xc000));
+	if (onoff) {
+		/* enable GPIO output */
+		val &= ~((led_config->gpio_output_enable >> 8) & 0xff);
+		val |=  (led_config->gpio_output_enable & 0xff);
+	} else {
+		/* disable GPIO output */
+		val &= ~((led_config->gpio_output_disable >> 8) & 0xff);
+		val |=  (led_config->gpio_output_disable & 0xff);
+	}
+	return au8522_writereg(state, 0x8000 |
+			       (led_config->gpio_output & ~0xc000), val);
+}
+
+/* led = 0 | off
+ * led = 1 | signal ok
+ * led = 2 | signal strong
+ * led < 0 | only light led if leds are currently off
+ */
+int au8522_led_ctrl(struct au8522_state *state, int led)
+{
+	struct au8522_led_config *led_config = state->config.led_cfg;
+	int i, ret = 0;
+
+	/* bail out if we can't control an LED */
+	if (!led_config || !led_config->gpio_leds ||
+	    !led_config->num_led_states || !led_config->led_states)
+		return 0;
+
+	if (led < 0) {
+		/* if LED is already lit, then leave it as-is */
+		if (state->led_state)
+			return 0;
+		else
+			led *= -1;
+	}
+
+	/* toggle LED if changing state */
+	if (state->led_state != led) {
+		u8 val;
+
+		dprintk("%s: %d\n", __func__, led);
+
+		au8522_led_gpio_enable(state, 1);
+
+		val = au8522_readreg(state, 0x4000 |
+				     (led_config->gpio_leds & ~0xc000));
+
+		/* start with all leds off */
+		for (i = 0; i < led_config->num_led_states; i++)
+			val &= ~led_config->led_states[i];
+
+		/* set selected LED state */
+		if (led < led_config->num_led_states)
+			val |= led_config->led_states[led];
+		else if (led_config->num_led_states)
+			val |=
+			led_config->led_states[led_config->num_led_states - 1];
+
+		ret = au8522_writereg(state, 0x8000 |
+				      (led_config->gpio_leds & ~0xc000), val);
+		if (ret < 0)
+			return ret;
+
+		state->led_state = led;
+
+		if (led == 0)
+			au8522_led_gpio_enable(state, 0);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(au8522_led_ctrl);
+
+int au8522_init(struct dvb_frontend *fe)
+{
+	struct au8522_state *state = fe->demodulator_priv;
+	dprintk("%s()\n", __func__);
+
+	state->operational_mode = AU8522_DIGITAL_MODE;
+
+	/* Clear out any state associated with the digital side of the
+	   chip, so that when it gets powered back up it won't think
+	   that it is already tuned */
+	state->current_frequency = 0;
+	state->current_modulation = VSB_8;
+
+	au8522_writereg(state, 0xa4, 1 << 5);
+
+	au8522_i2c_gate_ctrl(fe, 1);
+
+	return 0;
+}
+EXPORT_SYMBOL(au8522_init);
+
+int au8522_sleep(struct dvb_frontend *fe)
+{
+	struct au8522_state *state = fe->demodulator_priv;
+	dprintk("%s()\n", __func__);
+
+	/* Only power down if the digital side is currently using the chip */
+	if (state->operational_mode == AU8522_ANALOG_MODE) {
+		/* We're not in one of the expected power modes, which means
+		   that the DVB thread is probably telling us to go to sleep
+		   even though the analog frontend has already started using
+		   the chip.  So ignore the request */
+		return 0;
+	}
+
+	/* turn off led */
+	au8522_led_ctrl(state, 0);
+
+	/* Power down the chip */
+	au8522_writereg(state, 0xa4, 1 << 5);
+
+	state->current_frequency = 0;
+
+	return 0;
+}
+EXPORT_SYMBOL(au8522_sleep);
+
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "Enable verbose debug messages");
+
+MODULE_DESCRIPTION("Auvitek AU8522 QAM-B/ATSC Demodulator driver");
+MODULE_AUTHOR("Steven Toth");
+MODULE_LICENSE("GPL");