[PATCH 7/8] reset: amlogic: add auxiliary reset driver support

[Jerome Brunet]

Add support for the reset controller present in the audio clock
controller of the g12 and sm1 SoC families, using the auxiliary bus.

This is expected to replace the driver currently present directly
within the related clock driver.

Signed-off-by: Jerome Brunet <jbrunet at baylibre.com>
---
 drivers/reset/Kconfig                       |   1 +
 drivers/reset/reset-meson.c                 | 121 +++++++++++++++++++-
 include/soc/amlogic/meson-auxiliary-reset.h |  23 ++++
 3 files changed, 144 insertions(+), 1 deletion(-)
 create mode 100644 include/soc/amlogic/meson-auxiliary-reset.h

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 7112f5932609..2a316c469bcc 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -134,6 +134,7 @@ config RESET_MCHP_SPARX5
 config RESET_MESON
 	tristate "Meson Reset Driver"
 	depends on ARCH_MESON || COMPILE_TEST
+	select AUXILIARY_BUS
 	default ARCH_MESON
 	help
 	  This enables the reset driver for Amlogic Meson SoCs.
diff --git a/drivers/reset/reset-meson.c b/drivers/reset/reset-meson.c
index e34a10b15593..5cc767d50e8f 100644
--- a/drivers/reset/reset-meson.c
+++ b/drivers/reset/reset-meson.c
@@ -5,6 +5,7 @@
  * Copyright (c) 2016 BayLibre, SAS.
  * Author: Neil Armstrong <narmstrong at baylibre.com>
  */
+#include <linux/auxiliary_bus.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
@@ -16,6 +17,10 @@
 #include <linux/slab.h>
 #include <linux/types.h>
 
+#include <soc/amlogic/meson-auxiliary-reset.h>
+
+static DEFINE_IDA(meson_rst_aux_ida);
+
 struct meson_reset_param {
 	const struct reset_control_ops *reset_ops;
 	unsigned int reset_num;
@@ -30,6 +35,14 @@ struct meson_reset {
 	struct regmap *map;
 };
 
+struct meson_reset_adev {
+	struct auxiliary_device adev;
+	struct regmap *map;
+};
+
+#define to_meson_reset_adev(_adev) \
+	container_of((_adev), struct meson_reset_adev, adev)
+
 static void meson_reset_offset_and_bit(struct meson_reset *data,
 				       unsigned long id,
 				       unsigned int *offset,
@@ -218,6 +231,112 @@ static struct platform_driver meson_reset_pltf_driver = {
 };
 module_platform_driver(meson_reset_pltf_driver);
 
-MODULE_DESCRIPTION("Amlogic Meson Reset Controller driver");
+static const struct meson_reset_param meson_g12a_audio_param = {
+	.reset_ops	= &meson_reset_toggle_ops,
+	.reset_num	= 26,
+	.level_offset	= 0x24,
+};
+
+static const struct meson_reset_param meson_sm1_audio_param = {
+	.reset_ops	= &meson_reset_toggle_ops,
+	.reset_num	= 39,
+	.level_offset	= 0x28,
+};
+
+static const struct auxiliary_device_id meson_reset_aux_ids[] = {
+	{
+		.name = "axg-audio-clkc.rst-g12a",
+		.driver_data = (kernel_ulong_t)&meson_g12a_audio_param,
+	}, {
+		.name = "axg-audio-clkc.rst-sm1",
+		.driver_data = (kernel_ulong_t)&meson_sm1_audio_param,
+	},
+};
+MODULE_DEVICE_TABLE(auxiliary, meson_reset_aux_ids);
+
+static int meson_reset_aux_probe(struct auxiliary_device *adev,
+				 const struct auxiliary_device_id *id)
+{
+	const struct meson_reset_param *param =
+		(const struct meson_reset_param *)(id->driver_data);
+	struct meson_reset_adev *raux =
+		to_meson_reset_adev(adev);
+
+	return meson_reset_probe(&adev->dev, raux->map, param);
+}
+
+static struct auxiliary_driver meson_reset_aux_driver = {
+	.probe		= meson_reset_aux_probe,
+	.id_table	= meson_reset_aux_ids,
+};
+module_auxiliary_driver(meson_reset_aux_driver);
+
+static void meson_rst_aux_release(struct device *dev)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+	struct meson_reset_adev *raux =
+		to_meson_reset_adev(adev);
+
+	ida_free(&meson_rst_aux_ida, adev->id);
+	kfree(raux);
+}
+
+static void meson_rst_aux_unregister_adev(void *_adev)
+{
+	struct auxiliary_device *adev = _adev;
+
+	auxiliary_device_delete(adev);
+	auxiliary_device_uninit(adev);
+}
+
+int devm_meson_rst_aux_register(struct device *dev,
+				struct regmap *map,
+				const char *adev_name)
+{
+	struct meson_reset_adev *raux;
+	struct auxiliary_device *adev;
+	int ret;
+
+	raux = kzalloc(sizeof(*raux), GFP_KERNEL);
+	if (!raux)
+		return -ENOMEM;
+
+	ret = ida_alloc(&meson_rst_aux_ida, GFP_KERNEL);
+	if (ret < 0)
+		goto raux_free;
+
+	raux->map = map;
+
+	adev = &raux->adev;
+	adev->id = ret;
+	adev->name = adev_name;
+	adev->dev.parent = dev;
+	adev->dev.release = meson_rst_aux_release;
+	device_set_of_node_from_dev(&adev->dev, dev);
+
+	ret = auxiliary_device_init(adev);
+	if (ret)
+		goto ida_free;
+
+	ret = __auxiliary_device_add(adev, dev->driver->name);
+	if (ret) {
+		auxiliary_device_uninit(adev);
+		return ret;
+	}
+
+	return devm_add_action_or_reset(dev, meson_rst_aux_unregister_adev,
+					adev);
+
+ida_free:
+	ida_free(&meson_rst_aux_ida, adev->id);
+raux_free:
+	kfree(raux);
+	return ret;
+
+}
+EXPORT_SYMBOL_GPL(devm_meson_rst_aux_register);
+
+MODULE_DESCRIPTION("Amlogic Meson Reset driver");
 MODULE_AUTHOR("Neil Armstrong <narmstrong at baylibre.com>");
+MODULE_AUTHOR("Jerome Brunet <jbrunet at baylibre.com>");
 MODULE_LICENSE("Dual BSD/GPL");
diff --git a/include/soc/amlogic/meson-auxiliary-reset.h b/include/soc/amlogic/meson-auxiliary-reset.h
new file mode 100644
index 000000000000..8fdb02b18d8c
--- /dev/null
+++ b/include/soc/amlogic/meson-auxiliary-reset.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __SOC_AMLOGIC_MESON_AUX_RESET_H
+#define __SOC_AMLOGIC_MESON_AUX_RESET_H
+
+#include <linux/err.h>
+
+struct device;
+struct regmap;
+
+#ifdef CONFIG_RESET_MESON
+int devm_meson_rst_aux_register(struct device *dev,
+				struct regmap *map,
+				const char *adev_name);
+#else
+static inline int devm_meson_rst_aux_register(struct device *dev,
+					      struct regmap *map,
+					      const char *adev_name)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#endif /* __SOC_AMLOGIC_MESON8B_AUX_RESET_H */
-- 
2.43.0