Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 975 insertions, 0 deletions

diff --git a/sound/soc/codecs/simple-amplifier.c b/sound/soc/codecs/simple-amplifier.c
new file mode 100644
index 000000000..ca53b08c0
--- /dev/null
+++ b/sound/soc/codecs/simple-amplifier.c
@@ -0,0 +1,975 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Support for gpio amplifier
+ *   Copyright 2026 CS GROUP France
+ *   Author: Herve Codina <herve.codina@bootlin.com>
+ *
+ * Basic simple amplifier driver
+ *   Copyright (c) 2017 BayLibre, SAS.
+ *   Author: Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/bits.h>
+#include <linux/gpio/consumer.h>
+#include <linux/math.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <sound/soc.h>
+#include <linux/sort.h>
+#include <sound/tlv.h>
+
+struct simple_amp_single {
+	struct gpio_desc *gpio;
+	bool is_inverted;
+	int kctrl_val;
+	const char *control_name;
+};
+
+struct simple_amp_point {
+	u32 gpio_val;
+	int gain_db;
+};
+
+struct simple_amp_range {
+	unsigned int nb_points;
+	struct simple_amp_point min;
+	struct simple_amp_point max;
+};
+
+struct simple_amp_ranges {
+	unsigned int nb_ranges;
+	struct simple_amp_range *tab_ranges;
+};
+
+struct simple_amp_labels {
+	unsigned int nb_labels;
+	const char **tab_labels;
+};
+
+enum simple_amp_mode {
+	SIMPLE_AMP_MODE_NONE,
+	SIMPLE_AMP_MODE_RANGES,
+	SIMPLE_AMP_MODE_LABELS,
+};
+
+struct simple_amp_multi {
+	struct gpio_descs *gpios;
+	u32 kctrl_val;
+	u32 kctrl_max;
+	const char *control_name;
+	unsigned int *tlv_array;
+	enum simple_amp_mode mode;
+	union {
+		struct simple_amp_ranges ranges;
+		struct simple_amp_labels labels;
+	};
+};
+
+struct simple_amp_data {
+	unsigned int supports;
+#define SIMPLE_AUDIO_SUPPORT_PGA		BIT(0)
+#define SIMPLE_AUDIO_SUPPORT_POWER_SUPPLIES	BIT(1)
+#define SIMPLE_AUDIO_SUPPORT_MUTE		BIT(2)
+#define SIMPLE_AUDIO_SUPPORT_BYPASS		BIT(3)
+
+	const struct snd_soc_dapm_widget *dapm_widgets;
+	unsigned int num_dapm_widgets;
+	const struct snd_soc_dapm_route *dapm_routes;
+	unsigned int num_dapm_routes;
+};
+
+struct simple_amp {
+	const struct simple_amp_data *data;
+	struct gpio_desc *gpiod_enable;
+	struct simple_amp_single mute;
+	struct simple_amp_single bypass;
+	struct simple_amp_multi gain;
+};
+
+static int simple_amp_power_event(struct snd_soc_dapm_widget *w,
+				  struct snd_kcontrol *control, int event)
+{
+	struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
+	struct simple_amp *simple_amp = snd_soc_component_get_drvdata(c);
+	int val;
+
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		val = 1;
+		break;
+	case SND_SOC_DAPM_PRE_PMD:
+		val = 0;
+		break;
+	default:
+		WARN(1, "Unexpected event");
+		return -EINVAL;
+	}
+
+	gpiod_set_value_cansleep(simple_amp->gpiod_enable, val);
+
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget simple_amp_dapm_widgets[] = {
+	SND_SOC_DAPM_INPUT("INL"),
+	SND_SOC_DAPM_INPUT("INR"),
+	SND_SOC_DAPM_OUT_DRV_E("DRV", SND_SOC_NOPM, 0, 0, NULL, 0, simple_amp_power_event,
+			       (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)),
+	SND_SOC_DAPM_OUTPUT("OUTL"),
+	SND_SOC_DAPM_OUTPUT("OUTR"),
+	SND_SOC_DAPM_REGULATOR_SUPPLY("VCC", 20, 0),
+};
+
+static const struct snd_soc_dapm_route simple_amp_dapm_routes[] = {
+	{ "DRV", NULL, "INL" },
+	{ "DRV", NULL, "INR" },
+	{ "OUTL", NULL, "VCC" },
+	{ "OUTR", NULL, "VCC" },
+	{ "OUTL", NULL, "DRV" },
+	{ "OUTR", NULL, "DRV" },
+};
+
+static const struct snd_soc_dapm_widget simple_amp_mono_pga_dapm_widgets[] = {
+	SND_SOC_DAPM_INPUT("IN"),
+	SND_SOC_DAPM_OUTPUT("OUT"),
+	SND_SOC_DAPM_PGA_E("PGA", SND_SOC_NOPM, 0, 0, NULL, 0, simple_amp_power_event,
+			   (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)),
+	SND_SOC_DAPM_REGULATOR_SUPPLY("vdd", 0, 0),
+};
+
+static const struct snd_soc_dapm_route simple_amp_mono_pga_dapm_routes[] = {
+	{ "PGA", NULL, "IN" },
+	{ "PGA", NULL, "vdd" },
+	{ "OUT", NULL, "PGA" },
+};
+
+static const struct snd_soc_dapm_widget simple_amp_stereo_pga_dapm_widgets[] = {
+	SND_SOC_DAPM_INPUT("INL"),
+	SND_SOC_DAPM_INPUT("INR"),
+	SND_SOC_DAPM_OUTPUT("OUTL"),
+	SND_SOC_DAPM_OUTPUT("OUTR"),
+	SND_SOC_DAPM_PGA_E("PGA", SND_SOC_NOPM, 0, 0, NULL, 0, simple_amp_power_event,
+			   (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)),
+	SND_SOC_DAPM_REGULATOR_SUPPLY("vdd", 0, 0),
+};
+
+static const struct snd_soc_dapm_route simple_amp_stereo_pga_dapm_routes[] = {
+	{ "PGA", NULL, "INL" },
+	{ "PGA", NULL, "INR" },
+	{ "PGA", NULL, "vdd" },
+	{ "OUTL", NULL, "PGA" },
+	{ "OUTR", NULL, "PGA" },
+};
+
+static int simple_amp_single_kctrl_write_gpio(struct simple_amp_single *single,
+					      int kctrl_val)
+{
+	int gpio_val;
+
+	gpio_val = single->is_inverted ? !kctrl_val : kctrl_val;
+
+	return gpiod_set_value_cansleep(single->gpio, gpio_val);
+}
+
+static int simple_amp_single_kctrl_info(struct snd_kcontrol *kcontrol,
+					struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->count = 1;
+	uinfo->value.integer.min = 0;
+	uinfo->value.integer.max = 1;
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+	return 0;
+}
+
+static int simple_amp_single_kctrl_get(struct snd_kcontrol *kcontrol,
+				       struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_single *single = (struct simple_amp_single *)kcontrol->private_value;
+
+	ucontrol->value.integer.value[0] = single->kctrl_val;
+
+	return 0;
+}
+
+static int simple_amp_single_kctrl_put(struct snd_kcontrol *kcontrol,
+				       struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_single *single = (struct simple_amp_single *)kcontrol->private_value;
+	int kctrl_val;
+	int err;
+
+	kctrl_val = ucontrol->value.integer.value[0] ? 1 : 0;
+
+	if (kctrl_val == single->kctrl_val)
+		return 0;
+
+	err = simple_amp_single_kctrl_write_gpio(single, kctrl_val);
+	if (err)
+		return err;
+
+	single->kctrl_val = kctrl_val;
+
+	return 1; /* The value changed */
+}
+
+static int simple_amp_single_add_kcontrol(struct snd_soc_component *component,
+					  struct simple_amp_single *single)
+{
+	struct snd_kcontrol_new control = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = single->control_name,
+		.info = simple_amp_single_kctrl_info,
+		.get = simple_amp_single_kctrl_get,
+		.put = simple_amp_single_kctrl_put,
+		.private_value = (unsigned long)single,
+	};
+	int ret;
+
+	/* Be consistent between single->kctrl_val value and the GPIO value */
+	ret = simple_amp_single_kctrl_write_gpio(single, single->kctrl_val);
+	if (ret)
+		return ret;
+
+	return snd_soc_add_component_controls(component, &control, 1);
+}
+
+static u32 simple_amp_multi_ranges_kctrl_to_gpio(u32 kctrl_val,
+						 struct simple_amp_ranges *ranges)
+{
+	struct simple_amp_range *range;
+	u32 index = kctrl_val;
+	unsigned int i;
+
+	for (i = 0; i < ranges->nb_ranges; i++) {
+		range = &ranges->tab_ranges[i];
+
+		if (index < range->nb_points)
+			return (range->max.gpio_val >= range->min.gpio_val) ?
+				range->min.gpio_val + index :
+				range->min.gpio_val - index;
+
+		index -= range->nb_points;
+	}
+
+	/*
+	 * Given index out of possible ranges. This is shouldn't happen.
+	 * Signal the issue and return the maximum value
+	 */
+	WARN(1, "kctrl_val %u out of ranges\n", kctrl_val);
+	return ranges->tab_ranges[ranges->nb_ranges - 1].max.gpio_val;
+}
+
+static int simple_amp_multi_kctrl_write_gpios(struct simple_amp_multi *multi,
+					      u32 kctrl_val)
+{
+	DECLARE_BITMAP(bm, 32);
+	u32 gpio_val;
+
+	if (kctrl_val > multi->kctrl_max)
+		return -EINVAL;
+
+	if (multi->mode == SIMPLE_AMP_MODE_RANGES)
+		gpio_val = simple_amp_multi_ranges_kctrl_to_gpio(kctrl_val,
+								 &multi->ranges);
+	else
+		gpio_val = kctrl_val;
+
+	bitmap_from_arr32(bm, &gpio_val, multi->gpios->ndescs);
+
+	return gpiod_multi_set_value_cansleep(multi->gpios, bm);
+}
+
+static int simple_amp_multi_kctrl_int_info(struct snd_kcontrol *kcontrol,
+					   struct snd_ctl_elem_info *uinfo)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+
+	uinfo->count = 1;
+	uinfo->value.integer.min = 0;
+	uinfo->value.integer.max = multi->kctrl_max;
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	return 0;
+}
+
+static int simple_amp_multi_kctrl_int_get(struct snd_kcontrol *kcontrol,
+					  struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+
+	ucontrol->value.integer.value[0] = multi->kctrl_val;
+	return 0;
+}
+
+static int simple_amp_multi_kctrl_int_put(struct snd_kcontrol *kcontrol,
+					  struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+	u32 kctrl_val;
+	int ret;
+
+	kctrl_val = ucontrol->value.integer.value[0];
+
+	if (kctrl_val == multi->kctrl_val)
+		return 0;
+
+	ret = simple_amp_multi_kctrl_write_gpios(multi, kctrl_val);
+	if (ret)
+		return ret;
+
+	multi->kctrl_val = kctrl_val;
+
+	return 1; /* The value changed */
+}
+
+static int simple_amp_multi_kctrl_enum_info(struct snd_kcontrol *kcontrol,
+					    struct snd_ctl_elem_info *uinfo)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+
+	return snd_ctl_enum_info(uinfo, 1, multi->labels.nb_labels,
+				 multi->labels.tab_labels);
+}
+
+static int simple_amp_multi_kctrl_enum_get(struct snd_kcontrol *kcontrol,
+					   struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+
+	ucontrol->value.enumerated.item[0] = multi->kctrl_val;
+	return 0;
+}
+
+static int simple_amp_multi_kctrl_enum_put(struct snd_kcontrol *kcontrol,
+					   struct snd_ctl_elem_value *ucontrol)
+{
+	struct simple_amp_multi *multi = (struct simple_amp_multi *)kcontrol->private_value;
+	u32 kctrl_val;
+	int ret;
+
+	kctrl_val = ucontrol->value.enumerated.item[0];
+
+	if (kctrl_val == multi->kctrl_val)
+		return 0;
+
+	ret = simple_amp_multi_kctrl_write_gpios(multi, kctrl_val);
+	if (ret)
+		return ret;
+
+	multi->kctrl_val = kctrl_val;
+
+	return 1; /* The value changed */
+}
+
+static unsigned int *simple_amp_alloc_tlv_ranges(const struct simple_amp_ranges *ranges)
+{
+	unsigned int index;
+	unsigned int *tlv;
+	unsigned int *t;
+	unsigned int i;
+
+	tlv = kzalloc_objs(*tlv, 2 + ranges->nb_ranges * 6, GFP_KERNEL);
+	if (!tlv)
+		return NULL;
+
+	t = tlv;
+
+	/* Fill first TLV */
+	*t++ = SNDRV_CTL_TLVT_DB_RANGE; /* Tag */
+	*t++ = ranges->nb_ranges * 6 * sizeof(*tlv); /* Len */
+	/* Ranges are sorted from lower to higher value */
+	index = 0;
+	for (i = 0; i < ranges->nb_ranges; i++) {
+		/* Fill range item i */
+		*t++ = index;  /* min */
+		index += ranges->tab_ranges[i].nb_points;
+		*t++ = index - 1;  /* max */
+		*t++ = SNDRV_CTL_TLVT_DB_MINMAX; /* Tag */
+		*t++ = 2 * sizeof(*tlv); /* Len */
+		*t++ = ranges->tab_ranges[i].min.gain_db; /* min_dB */
+		*t++ = ranges->tab_ranges[i].max.gain_db; /* max_dB */
+	}
+
+	return tlv;
+}
+
+static int simple_amp_multi_add_kcontrol(struct snd_soc_component *component,
+					 struct simple_amp_multi *multi)
+{
+	struct snd_kcontrol_new control = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = multi->control_name,
+		.info = simple_amp_multi_kctrl_int_info,
+		.get = simple_amp_multi_kctrl_int_get,
+		.put = simple_amp_multi_kctrl_int_put,
+		.private_value = (unsigned long)multi,
+	};
+	int ret;
+
+	switch (multi->mode) {
+	case SIMPLE_AMP_MODE_RANGES:
+		multi->tlv_array = simple_amp_alloc_tlv_ranges(&multi->ranges);
+		if (!multi->tlv_array)
+			return -ENOMEM;
+
+		control.access = SNDRV_CTL_ELEM_ACCESS_TLV_READ |
+				 SNDRV_CTL_ELEM_ACCESS_READWRITE;
+		control.tlv.p = multi->tlv_array;
+		break;
+
+	case SIMPLE_AMP_MODE_LABELS:
+		/* Use enumerated values */
+		control.info = simple_amp_multi_kctrl_enum_info;
+		control.get = simple_amp_multi_kctrl_enum_get;
+		control.put = simple_amp_multi_kctrl_enum_put;
+		break;
+
+	case SIMPLE_AMP_MODE_NONE:
+		/* Already set control configuration is enough */
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	/* Be consistent between multi->kctrl_val value and the GPIOs value */
+	ret = simple_amp_multi_kctrl_write_gpios(multi, multi->kctrl_val);
+	if (ret)
+		goto err_free_tlv_array;
+
+	ret = snd_soc_add_component_controls(component, &control, 1);
+	if (ret)
+		goto err_free_tlv_array;
+
+	return 0;
+
+err_free_tlv_array:
+	kfree(multi->tlv_array);
+	return ret;
+}
+
+static int simple_amp_add_basic_dapm(struct snd_soc_component *component)
+{
+	struct snd_soc_dapm_context *dapm = snd_soc_component_to_dapm(component);
+	struct simple_amp *simple_amp = snd_soc_component_get_drvdata(component);
+	struct device *dev = component->dev;
+	int ret;
+
+	/* Add basic dapm widgets and routes */
+	ret = snd_soc_dapm_new_controls(dapm, simple_amp->data->dapm_widgets,
+					simple_amp->data->num_dapm_widgets);
+	if (ret) {
+		dev_err(dev, "Failed to add basic dapm widgets (%d)\n", ret);
+		return ret;
+	}
+
+	ret = snd_soc_dapm_add_routes(dapm, simple_amp->data->dapm_routes,
+				      simple_amp->data->num_dapm_routes);
+	if (ret) {
+		dev_err(dev, "Failed to add basic dapm routes (%d)\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+struct simple_amp_supply {
+	const char *prop_name;
+	const struct snd_soc_dapm_widget dapm_widget;
+	const struct snd_soc_dapm_route dapm_route;
+};
+
+static const struct simple_amp_supply simple_amp_supplies[] = {
+	{
+		.prop_name = "vddio-supply",
+		.dapm_widget = SND_SOC_DAPM_REGULATOR_SUPPLY("vddio", 0, 0),
+		.dapm_route = { "PGA", NULL, "vddio" },
+	}, {
+		.prop_name = "vdda1-supply",
+		.dapm_widget = SND_SOC_DAPM_REGULATOR_SUPPLY("vdda1", 0, 0),
+		.dapm_route = { "PGA", NULL, "vdda1" },
+	}, {
+		.prop_name = "vdda2-supply",
+		.dapm_widget = SND_SOC_DAPM_REGULATOR_SUPPLY("vdda2", 0, 0),
+		.dapm_route = { "PGA", NULL, "vdda2" },
+	},
+	{ /* End of list */}
+};
+
+static int simple_amp_add_power_supplies(struct snd_soc_component *component)
+{
+	struct snd_soc_dapm_context *dapm = snd_soc_component_to_dapm(component);
+	struct simple_amp *simple_amp = snd_soc_component_get_drvdata(component);
+	const struct simple_amp_supply *supply;
+	struct device *dev = component->dev;
+	int ret;
+
+	/*
+	 * Those additional power supplies are attached to the PGA.
+	 * If PGA is not supported, simply skipped them.
+	 */
+	if (!(simple_amp->data->supports & SIMPLE_AUDIO_SUPPORT_PGA)) {
+		dev_err(dev, "Extra power supplied need PGA\n");
+		return -EINVAL;
+	}
+
+	supply = simple_amp_supplies;
+	do {
+		if (!of_property_present(dev->of_node, supply->prop_name))
+			continue;
+
+		ret = snd_soc_dapm_new_controls(dapm, &supply->dapm_widget, 1);
+		if (ret) {
+			dev_err(dev, "Failed to add control for '%s' (%d)\n",
+				supply->prop_name, ret);
+			return ret;
+		}
+		ret = snd_soc_dapm_add_routes(dapm, &supply->dapm_route, 1);
+		if (ret) {
+			dev_err(dev, "Failed to add route for '%s' (%d)\n",
+				supply->prop_name, ret);
+			return ret;
+		}
+	} while ((++supply)->prop_name);
+
+	return 0;
+}
+
+static int simple_amp_component_probe(struct snd_soc_component *component)
+{
+	struct simple_amp *simple_amp = snd_soc_component_get_drvdata(component);
+	int ret;
+
+	/* Add basic dapm widgets and routes */
+	ret = simple_amp_add_basic_dapm(component);
+	if (ret)
+		return ret;
+
+	/* Add additional power supplies */
+	if (simple_amp->data->supports & SIMPLE_AUDIO_SUPPORT_POWER_SUPPLIES) {
+		ret = simple_amp_add_power_supplies(component);
+		if (ret)
+			return ret;
+	}
+
+	if (simple_amp->mute.gpio) {
+		/*
+		 * The name of the GPIO used is mute. According to this name, 1
+		 * means muted and 0 means un-muted.
+		 *
+		 * An inversion is expected by ALSA. Indeed from ALSA point of
+		 * view, 1 means 'on' (un-muted) and 0 means 'off' (muted).
+		 */
+		simple_amp->mute.is_inverted = true;
+		simple_amp->mute.kctrl_val = 1; /* Un-muted */
+		ret = simple_amp_single_add_kcontrol(component, &simple_amp->mute);
+		if (ret)
+			return ret;
+	}
+
+	if (simple_amp->bypass.gpio) {
+		ret = simple_amp_single_add_kcontrol(component, &simple_amp->bypass);
+		if (ret)
+			return ret;
+	}
+
+	if (simple_amp->gain.gpios) {
+		ret = simple_amp_multi_add_kcontrol(component, &simple_amp->gain);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void simple_amp_component_remove(struct snd_soc_component *component)
+{
+	struct simple_amp *simple_amp = snd_soc_component_get_drvdata(component);
+
+	kfree(simple_amp->gain.tlv_array);
+	simple_amp->gain.tlv_array = NULL;
+}
+
+static const struct snd_soc_component_driver simple_amp_component_driver = {
+	.probe = simple_amp_component_probe,
+	.remove = simple_amp_component_remove,
+};
+
+static int simple_amp_parse_single_gpio(struct device *dev,
+					struct simple_amp_single *single,
+					const char *gpio_property)
+{
+	/* Start with the inactive value */
+	single->is_inverted = false;
+	single->kctrl_val = 0;
+	single->gpio = devm_gpiod_get_optional(dev, gpio_property, GPIOD_OUT_LOW);
+	if (IS_ERR(single->gpio))
+		return dev_err_probe(dev, PTR_ERR(single->gpio),
+				     "Failed to get '%s' gpio\n",
+				     gpio_property);
+	return 0;
+}
+
+static int simple_amp_cmp_ranges(const void *a, const void *b)
+{
+	const struct simple_amp_range *a_range = a;
+	const struct simple_amp_range *b_range = b;
+
+	/* Ranges a and b don't overlap. This has been already checked */
+
+	return a_range->min.gain_db - b_range->max.gain_db;
+}
+
+static int simple_amp_check_new_range(const struct simple_amp_range *new_range,
+				      const struct simple_amp_range *tab_ranges,
+				      unsigned int nb_ranges)
+{
+	unsigned int i;
+
+	for (i = 0; i < nb_ranges; i++) {
+		/* Check for range overlaps */
+		if (new_range->min.gain_db >= tab_ranges[i].min.gain_db &&
+		    new_range->min.gain_db <= tab_ranges[i].max.gain_db)
+			return -EINVAL;
+
+		if (new_range->max.gain_db >= tab_ranges[i].min.gain_db &&
+		    new_range->max.gain_db <= tab_ranges[i].max.gain_db)
+			return -EINVAL;
+
+		if (new_range->min.gain_db <= tab_ranges[i].min.gain_db &&
+		    new_range->max.gain_db >= tab_ranges[i].max.gain_db)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+static int simple_amp_parse_ranges(struct device *dev,
+				   struct simple_amp_multi *multi,
+				   const char *ranges_property)
+{
+	struct simple_amp_ranges *ranges = &multi->ranges;
+	struct simple_amp_range *range;
+	struct device_node *np = dev->of_node;
+	struct simple_amp_point first_point;
+	unsigned int max_gpio_val;
+	unsigned int i;
+	int ret;
+	u32 u;
+	s32 s;
+
+	max_gpio_val = (1 << multi->gpios->ndescs) - 1;
+
+	ret = of_property_count_u32_elems(np, ranges_property);
+	if (ret < 0)
+		return ret;
+
+	/* The ranges array cannot be empty */
+	if (ret == 0)
+		return -EINVAL;
+	/*
+	 * One range item is composed of 2 points and each point is composed of
+	 * 2 values.
+	 */
+	if (ret % 4)
+		return -EINVAL;
+
+	ranges->nb_ranges = ret / 4;
+
+	/* The worst case is one range per possible gpio value */
+	if (ranges->nb_ranges > max_gpio_val + 1)
+		return -EINVAL;
+
+	ranges->tab_ranges = devm_kcalloc(dev, ranges->nb_ranges,
+					  sizeof(*ranges->tab_ranges),
+					  GFP_KERNEL);
+	if (!ranges->tab_ranges)
+		return -ENOMEM;
+
+	multi->kctrl_max = 0;
+	for (i = 0; i < ranges->nb_ranges; i++) {
+		range = &ranges->tab_ranges[i];
+
+		/* First gpios value */
+		ret = of_property_read_u32_index(np, ranges_property, i * 4, &u);
+		if (ret)
+			return ret;
+		if (u > max_gpio_val)
+			return -EINVAL;
+
+		range->min.gpio_val = u;
+
+		/* First Gain value */
+		ret = of_property_read_s32_index(np, ranges_property, i * 4 + 1, &s);
+		if (ret)
+			return ret;
+
+		range->min.gain_db = s;
+
+		/* Second gpios value */
+		ret = of_property_read_u32_index(np, ranges_property, i * 4 + 2, &u);
+		if (ret)
+			return ret;
+		if (u > max_gpio_val)
+			return -EINVAL;
+
+		range->max.gpio_val = u;
+
+		/* Second Gain value */
+		ret = of_property_read_s32_index(np, ranges_property, i * 4 + 3, &s);
+		if (ret)
+			return ret;
+
+		range->max.gain_db = s;
+
+		/* Save the first point for later usage */
+		if (i == 0)
+			first_point = range->min;
+
+		/* Fix min and max if needed */
+		if (range->min.gain_db > range->max.gain_db)
+			swap(range->min, range->max);
+
+		ret = simple_amp_check_new_range(range, ranges->tab_ranges, i);
+		if (ret)
+			return ret;
+
+		range->nb_points = abs_diff(range->min.gpio_val,
+					    range->max.gpio_val) + 1;
+
+		multi->kctrl_max += range->nb_points;
+	}
+
+	multi->kctrl_max -= 1;
+
+	/* Sort the tab_range array by gain_db value */
+	sort(ranges->tab_ranges, ranges->nb_ranges, sizeof(*ranges->tab_ranges),
+	     simple_amp_cmp_ranges, NULL);
+
+	/*
+	 * multi->kctrl_val is the index in tab_ranges.
+	 *
+	 * Choose to have the initial amplification value set to the first point
+	 * available in the first range available in the tab_ranges array before
+	 * sorting.
+	 *
+	 * This first point has been identified before sorting. Search for it in
+	 * the sorted array in order to set the multi->kctrl_val initial value.
+	 */
+	multi->kctrl_val = 0;
+	for (i = 0; i < ranges->nb_ranges; i++) {
+		range = &ranges->tab_ranges[i];
+
+		if (range->min.gpio_val == first_point.gpio_val &&
+		    range->min.gain_db == first_point.gain_db)
+			break;
+
+		multi->kctrl_val += range->nb_points;
+
+		if (range->max.gpio_val == first_point.gpio_val &&
+		    range->max.gain_db == first_point.gain_db) {
+			multi->kctrl_val--;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static int simple_amp_parse_labels(struct device *dev,
+				   struct simple_amp_multi *multi,
+				   const char *labels_property)
+{
+	struct simple_amp_labels *labels = &multi->labels;
+	struct device_node *np = dev->of_node;
+	int ret;
+
+	ret = of_property_count_strings(np, labels_property);
+	if (ret < 0)
+		return ret;
+
+	/* The labels array cannot be empty */
+	if (ret == 0)
+		return -EINVAL;
+
+	labels->nb_labels = ret;
+	if (labels->nb_labels > (1 << multi->gpios->ndescs))
+		return -EINVAL;
+
+	labels->tab_labels = devm_kcalloc(dev, labels->nb_labels,
+					  sizeof(*labels->tab_labels),
+					  GFP_KERNEL);
+	if (!labels->tab_labels)
+		return -ENOMEM;
+
+	multi->kctrl_max = labels->nb_labels - 1;
+	multi->kctrl_val = 0;
+
+	return of_property_read_string_array(np, labels_property, labels->tab_labels,
+					     labels->nb_labels);
+}
+
+static int simple_amp_parse_multi_gpio(struct device *dev,
+				       struct simple_amp_multi *multi,
+				       const char *gpios_property,
+				       const char *ranges_property,
+				       const char *labels_property)
+{
+	struct device_node *np = dev->of_node;
+	int ret;
+
+	/* Start with the value 0 (GPIO inactive). Can be changed later */
+	multi->kctrl_val = 0;
+	multi->gpios = devm_gpiod_get_array_optional(dev, gpios_property, GPIOD_OUT_LOW);
+	if (IS_ERR(multi->gpios))
+		return dev_err_probe(dev, PTR_ERR(multi->gpios),
+				     "Failed to get '%s' gpios\n",
+				     gpios_property);
+	if (!multi->gpios)
+		return 0;
+
+	if (multi->gpios->ndescs > 16)
+		return dev_err_probe(dev, -EINVAL,
+				     "Number of '%s' gpios limited to 16\n",
+				     gpios_property);
+
+	/* Set default value for the kctrl_max. Can be changed later */
+	multi->kctrl_max = (1 << multi->gpios->ndescs) - 1;
+
+	multi->mode = SIMPLE_AMP_MODE_NONE;
+	if (of_property_present(np, ranges_property)) {
+		ret = simple_amp_parse_ranges(dev, multi, ranges_property);
+		if (ret < 0)
+			return dev_err_probe(dev, ret, "Failed to parse '%s'\n",
+					     ranges_property);
+		multi->mode = SIMPLE_AMP_MODE_RANGES;
+	} else if (of_property_present(np, labels_property)) {
+		ret = simple_amp_parse_labels(dev, multi, labels_property);
+		if (ret < 0)
+			return dev_err_probe(dev, ret, "Failed to parse '%s'\n",
+					     labels_property);
+
+		multi->mode = SIMPLE_AMP_MODE_LABELS;
+	}
+
+	return 0;
+}
+
+static int simple_amp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct simple_amp *simple_amp;
+	int ret;
+
+	simple_amp = devm_kzalloc(dev, sizeof(*simple_amp), GFP_KERNEL);
+	if (!simple_amp)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, simple_amp);
+
+	simple_amp->data = of_device_get_match_data(dev);
+	if (!simple_amp->data)
+		return -EINVAL;
+
+	simple_amp->gpiod_enable = devm_gpiod_get_optional(dev, "enable",
+							   GPIOD_OUT_LOW);
+	if (IS_ERR(simple_amp->gpiod_enable))
+		return dev_err_probe(dev, PTR_ERR(simple_amp->gpiod_enable),
+				     "Failed to get 'enable' gpio");
+
+	if (simple_amp->data->supports & SIMPLE_AUDIO_SUPPORT_MUTE) {
+		ret = simple_amp_parse_single_gpio(dev, &simple_amp->mute, "mute");
+		if (ret)
+			return ret;
+	}
+
+	if (simple_amp->data->supports & SIMPLE_AUDIO_SUPPORT_BYPASS) {
+		ret = simple_amp_parse_single_gpio(dev, &simple_amp->bypass, "bypass");
+		if (ret)
+			return ret;
+	}
+
+	if (simple_amp->data->supports & SIMPLE_AUDIO_SUPPORT_PGA) {
+		ret = simple_amp_parse_multi_gpio(dev, &simple_amp->gain, "gain",
+						  "gain-ranges", "gain-labels");
+		if (ret)
+			return ret;
+	}
+
+	/* Set controls name */
+	simple_amp->gain.control_name = "Volume";
+	simple_amp->mute.control_name = "Switch";
+	simple_amp->bypass.control_name = "Bypass Switch";
+
+	if (simple_amp->gain.mode == SIMPLE_AMP_MODE_LABELS) {
+		/*
+		 * The gain widget control will use enumerated values.
+		 *
+		 * Having just "Voltage" and "Switch" widget names with
+		 * enumerated values and boolean value can confuse ALSA in terms
+		 * of possible values (strings).
+		 *
+		 * Make things clear and avoid the just "Switch" name in that
+		 * case.
+		 */
+		simple_amp->mute.control_name = "Out Switch";
+	}
+
+	return devm_snd_soc_register_component(dev,
+					       &simple_amp_component_driver,
+					       NULL, 0);
+}
+
+static const struct simple_amp_data simple_audio_amplifier_data = {
+	.dapm_widgets		= simple_amp_dapm_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(simple_amp_dapm_widgets),
+	.dapm_routes		= simple_amp_dapm_routes,
+	.num_dapm_routes	= ARRAY_SIZE(simple_amp_dapm_routes),
+};
+
+static const struct simple_amp_data simple_audio_mono_pga_data = {
+	.supports		= SIMPLE_AUDIO_SUPPORT_PGA |
+				  SIMPLE_AUDIO_SUPPORT_POWER_SUPPLIES |
+				  SIMPLE_AUDIO_SUPPORT_MUTE |
+				  SIMPLE_AUDIO_SUPPORT_BYPASS,
+	.dapm_widgets		= simple_amp_mono_pga_dapm_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(simple_amp_mono_pga_dapm_widgets),
+	.dapm_routes		= simple_amp_mono_pga_dapm_routes,
+	.num_dapm_routes	= ARRAY_SIZE(simple_amp_mono_pga_dapm_routes),
+};
+
+static const struct simple_amp_data simple_audio_stereo_pga_data = {
+	.supports		= SIMPLE_AUDIO_SUPPORT_PGA |
+				  SIMPLE_AUDIO_SUPPORT_POWER_SUPPLIES |
+				  SIMPLE_AUDIO_SUPPORT_MUTE |
+				  SIMPLE_AUDIO_SUPPORT_BYPASS,
+	.dapm_widgets		= simple_amp_stereo_pga_dapm_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(simple_amp_stereo_pga_dapm_widgets),
+	.dapm_routes		= simple_amp_stereo_pga_dapm_routes,
+	.num_dapm_routes	= ARRAY_SIZE(simple_amp_stereo_pga_dapm_routes),
+};
+
+static const struct of_device_id simple_amp_ids[] = {
+	{ .compatible = "dioo,dio2125",		  .data = &simple_audio_amplifier_data},
+	{ .compatible = "simple-audio-amplifier", .data = &simple_audio_amplifier_data},
+	{ .compatible = "gpio-audio-amp-mono",	  .data = &simple_audio_mono_pga_data},
+	{ .compatible = "gpio-audio-amp-stereo",  .data = &simple_audio_stereo_pga_data},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, simple_amp_ids);
+
+static struct platform_driver simple_amp_driver = {
+	.driver = {
+		.name = "simple-amplifier",
+		.of_match_table = simple_amp_ids,
+	},
+	.probe = simple_amp_probe,
+};
+
+module_platform_driver(simple_amp_driver);
+
+MODULE_DESCRIPTION("ASoC Simple Audio Amplifier driver");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
+MODULE_LICENSE("GPL");