reset: amlogic: split the device core and platform probe

To prepare the addition of the auxiliary device support, split
out the device coomon functions from the probe of the platform device.

The device core function will be common to both the platform and auxiliary
driver.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20240910-meson-rst-aux-v5-8-60be62635d3e@baylibre.com
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

5 files changed, 167 insertions, 108 deletions

diff --git a/drivers/reset/amlogic/Kconfig b/drivers/reset/amlogic/Kconfig
index 532e6a4f7865..1d77987088f4 100644
--- a/drivers/reset/amlogic/Kconfig
+++ b/drivers/reset/amlogic/Kconfig
@@ -1,10 +1,15 @@
+config RESET_MESON_COMMON
+	tristate
+	select REGMAP
+
 config RESET_MESON
 	tristate "Meson Reset Driver"
 	depends on ARCH_MESON || COMPILE_TEST
 	default ARCH_MESON
 	select REGMAP_MMIO
+	select RESET_MESON_COMMON
 	help
-	  This enables the reset driver for Amlogic Meson SoCs.
+	  This enables the reset driver for Amlogic SoCs.
 
 config RESET_MESON_AUDIO_ARB
 	tristate "Meson Audio Memory Arbiter Reset Driver"
diff --git a/drivers/reset/amlogic/Makefile b/drivers/reset/amlogic/Makefile
index 55509fc78513..74aaa2fb5e13 100644
--- a/drivers/reset/amlogic/Makefile
+++ b/drivers/reset/amlogic/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_RESET_MESON) += reset-meson.o
+obj-$(CONFIG_RESET_MESON_COMMON) += reset-meson-common.o
 obj-$(CONFIG_RESET_MESON_AUDIO_ARB) += reset-meson-audio-arb.o
diff --git a/drivers/reset/amlogic/reset-meson-common.c b/drivers/reset/amlogic/reset-meson-common.c
new file mode 100644
index 000000000000..d57544801ae9
--- /dev/null
+++ b/drivers/reset/amlogic/reset-meson-common.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/*
+ * Amlogic Meson Reset core functions
+ *
+ * Copyright (c) 2016-2024 BayLibre, SAS.
+ * Authors: Neil Armstrong <narmstrong@baylibre.com>
+ *          Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#include "reset-meson.h"
+
+struct meson_reset {
+	const struct meson_reset_param *param;
+	struct reset_controller_dev rcdev;
+	struct regmap *map;
+};
+
+static void meson_reset_offset_and_bit(struct meson_reset *data,
+				       unsigned long id,
+				       unsigned int *offset,
+				       unsigned int *bit)
+{
+	unsigned int stride = regmap_get_reg_stride(data->map);
+
+	*offset = (id / (stride * BITS_PER_BYTE)) * stride;
+	*bit = id % (stride * BITS_PER_BYTE);
+}
+
+static int meson_reset_reset(struct reset_controller_dev *rcdev,
+			     unsigned long id)
+{
+	struct meson_reset *data =
+		container_of(rcdev, struct meson_reset, rcdev);
+	unsigned int offset, bit;
+
+	meson_reset_offset_and_bit(data, id, &offset, &bit);
+	offset += data->param->reset_offset;
+
+	return regmap_write(data->map, offset, BIT(bit));
+}
+
+static int meson_reset_level(struct reset_controller_dev *rcdev,
+			    unsigned long id, bool assert)
+{
+	struct meson_reset *data =
+		container_of(rcdev, struct meson_reset, rcdev);
+	unsigned int offset, bit;
+
+	meson_reset_offset_and_bit(data, id, &offset, &bit);
+	offset += data->param->level_offset;
+	assert ^= data->param->level_low_reset;
+
+	return regmap_update_bits(data->map, offset,
+				  BIT(bit), assert ? BIT(bit) : 0);
+}
+
+static int meson_reset_status(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	struct meson_reset *data =
+		container_of(rcdev, struct meson_reset, rcdev);
+	unsigned int val, offset, bit;
+
+	meson_reset_offset_and_bit(data, id, &offset, &bit);
+	offset += data->param->level_offset;
+
+	regmap_read(data->map, offset, &val);
+	val = !!(BIT(bit) & val);
+
+	return val ^ data->param->level_low_reset;
+}
+
+static int meson_reset_assert(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	return meson_reset_level(rcdev, id, true);
+}
+
+static int meson_reset_deassert(struct reset_controller_dev *rcdev,
+				unsigned long id)
+{
+	return meson_reset_level(rcdev, id, false);
+}
+
+static const struct reset_control_ops meson_reset_ops = {
+	.reset		= meson_reset_reset,
+	.assert		= meson_reset_assert,
+	.deassert	= meson_reset_deassert,
+	.status		= meson_reset_status,
+};
+
+int meson_reset_controller_register(struct device *dev, struct regmap *map,
+				    const struct meson_reset_param *param)
+{
+	struct meson_reset *data;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->param = param;
+	data->map = map;
+	data->rcdev.owner = dev->driver->owner;
+	data->rcdev.nr_resets = param->reset_num;
+	data->rcdev.ops = &meson_reset_ops;
+	data->rcdev.of_node = dev->of_node;
+
+	return devm_reset_controller_register(dev, &data->rcdev);
+}
+EXPORT_SYMBOL_NS_GPL(meson_reset_controller_register, MESON_RESET);
+
+MODULE_DESCRIPTION("Amlogic Meson Reset Core function");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_IMPORT_NS(MESON_RESET);
diff --git a/drivers/reset/amlogic/reset-meson.c b/drivers/reset/amlogic/reset-meson.c
index af690d3012ec..feb19bf6da77 100644
--- a/drivers/reset/amlogic/reset-meson.c
+++ b/drivers/reset/amlogic/reset-meson.c
@@ -2,106 +2,20 @@
 /*
  * Amlogic Meson Reset Controller driver
  *
- * Copyright (c) 2016 BayLibre, SAS.
- * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (c) 2016-2024 BayLibre, SAS.
+ * Authors: Neil Armstrong <narmstrong@baylibre.com>
+ *          Jerome Brunet <jbrunet@baylibre.com>
  */
+
 #include <linux/err.h>
-#include <linux/init.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/reset-controller.h>
-#include <linux/slab.h>
-#include <linux/types.h>
-
-struct meson_reset_param {
-	unsigned int reset_num;
-	unsigned int reset_offset;
-	unsigned int level_offset;
-	bool level_low_reset;
-};
-
-struct meson_reset {
-	const struct meson_reset_param *param;
-	struct reset_controller_dev rcdev;
-	struct regmap *map;
-};
-
-static void meson_reset_offset_and_bit(struct meson_reset *data,
-				       unsigned long id,
-				       unsigned int *offset,
-				       unsigned int *bit)
-{
-	unsigned int stride = regmap_get_reg_stride(data->map);
-
-	*offset = (id / (stride * BITS_PER_BYTE)) * stride;
-	*bit = id % (stride * BITS_PER_BYTE);
-}
-
-static int meson_reset_reset(struct reset_controller_dev *rcdev,
-			     unsigned long id)
-{
-	struct meson_reset *data =
-		container_of(rcdev, struct meson_reset, rcdev);
-	unsigned int offset, bit;
-
-	meson_reset_offset_and_bit(data, id, &offset, &bit);
-	offset += data->param->reset_offset;
-
-	return regmap_write(data->map, offset, BIT(bit));
-}
-
-static int meson_reset_level(struct reset_controller_dev *rcdev,
-			    unsigned long id, bool assert)
-{
-	struct meson_reset *data =
-		container_of(rcdev, struct meson_reset, rcdev);
-	unsigned int offset, bit;
-
-	meson_reset_offset_and_bit(data, id, &offset, &bit);
-	offset += data->param->level_offset;
-	assert ^= data->param->level_low_reset;
 
-	return regmap_update_bits(data->map, offset,
-				  BIT(bit), assert ? BIT(bit) : 0);
-}
-
-static int meson_reset_status(struct reset_controller_dev *rcdev,
-			      unsigned long id)
-{
-	struct meson_reset *data =
-		container_of(rcdev, struct meson_reset, rcdev);
-	unsigned int val, offset, bit;
-
-	meson_reset_offset_and_bit(data, id, &offset, &bit);
-	offset += data->param->level_offset;
-
-	regmap_read(data->map, offset, &val);
-	val = !!(BIT(bit) & val);
-
-	return val ^ data->param->level_low_reset;
-}
-
-static int meson_reset_assert(struct reset_controller_dev *rcdev,
-			      unsigned long id)
-{
-	return meson_reset_level(rcdev, id, true);
-}
-
-static int meson_reset_deassert(struct reset_controller_dev *rcdev,
-				unsigned long id)
-{
-	return meson_reset_level(rcdev, id, false);
-}
-
-static const struct reset_control_ops meson_reset_ops = {
-	.reset		= meson_reset_reset,
-	.assert		= meson_reset_assert,
-	.deassert	= meson_reset_deassert,
-	.status		= meson_reset_status,
-};
+#include "reset-meson.h"
 
 static const struct meson_reset_param meson8b_param = {
 	.reset_num	= 256,
@@ -151,33 +65,25 @@ static const struct regmap_config regmap_config = {
 
 static int meson_reset_probe(struct platform_device *pdev)
 {
+	const struct meson_reset_param *param;
 	struct device *dev = &pdev->dev;
-	struct meson_reset *data;
+	struct regmap *map;
 	void __iomem *base;
 
-	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
 	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
-	data->param = device_get_match_data(dev);
-	if (!data->param)
+	param = device_get_match_data(dev);
+	if (!param)
 		return -ENODEV;
 
-	data->map = devm_regmap_init_mmio(dev, base, &regmap_config);
-	if (IS_ERR(data->map))
-		return dev_err_probe(dev, PTR_ERR(data->map),
+	map = devm_regmap_init_mmio(dev, base, &regmap_config);
+	if (IS_ERR(map))
+		return dev_err_probe(dev, PTR_ERR(map),
 				     "can't init regmap mmio region\n");
 
-	data->rcdev.owner = THIS_MODULE;
-	data->rcdev.nr_resets = data->param->reset_num;
-	data->rcdev.ops = &meson_reset_ops;
-	data->rcdev.of_node = dev->of_node;
-
-	return devm_reset_controller_register(dev, &data->rcdev);
+	return meson_reset_controller_register(dev, map, param);
 }
 
 static struct platform_driver meson_reset_driver = {
@@ -191,4 +97,6 @@ module_platform_driver(meson_reset_driver);
 
 MODULE_DESCRIPTION("Amlogic Meson Reset Controller driver");
 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
 MODULE_LICENSE("Dual BSD/GPL");
+MODULE_IMPORT_NS(MESON_RESET);
diff --git a/drivers/reset/amlogic/reset-meson.h b/drivers/reset/amlogic/reset-meson.h
new file mode 100644
index 000000000000..4e1dbd7569c5
--- /dev/null
+++ b/drivers/reset/amlogic/reset-meson.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
+/*
+ * Copyright (c) 2024 BayLibre, SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#ifndef __MESON_RESET_H
+#define __MESON_RESET_H
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+struct meson_reset_param {
+	unsigned int reset_num;
+	unsigned int reset_offset;
+	unsigned int level_offset;
+	bool level_low_reset;
+};
+
+int meson_reset_controller_register(struct device *dev, struct regmap *map,
+				    const struct meson_reset_param *param);
+
+#endif /* __MESON_RESET_H */