clock, reset: microchip: move all mpfs reset code to the reset subsystem

Stephen and Philipp, while reviewing patches, said that all of the aux
device creation and the register read/write code could be moved to the
reset subsystem, leaving the clock driver with no implementations of
reset_* functions at all. Move them.

Suggested-by: Philipp Zabel <[email protected]>
Suggested-by: Stephen Boyd <[email protected]>
Signed-off-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/20240424-strangle-sharpener-34755c5e6e3e@spud
Signed-off-by: Stephen Boyd <[email protected]>

Author: ConchuOD

drivers/clk/microchip/clk-mpfs.c

@@ -4,12 +4,10 @@
  *
  * Copyright (C) 2020-2022 Microchip Technology Inc. All rights reserved.
  */
-#include <linux/auxiliary_bus.h>
 #include <linux/clk-provider.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
-#include <linux/slab.h>
 #include <dt-bindings/clock/microchip,mpfs-clock.h>
 #include <soc/microchip/mpfs.h>
 
@@ -361,93 +359,6 @@ static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_c
 	return 0;
 }
 
-/*
- * Peripheral clock resets
- */
-
-#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
-
-u32 mpfs_reset_read(struct device *dev)
-{
-	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
-
-	return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
-}
-EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);
-
-void mpfs_reset_write(struct device *dev, u32 val)
-{
-	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
-
-	writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
-}
-EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);
-
-static void mpfs_reset_unregister_adev(void *_adev)
-{
-	struct auxiliary_device *adev = _adev;
-
-	auxiliary_device_delete(adev);
-	auxiliary_device_uninit(adev);
-}
-
-static void mpfs_reset_adev_release(struct device *dev)
-{
-	struct auxiliary_device *adev = to_auxiliary_dev(dev);
-
-	kfree(adev);
-}
-
-static struct auxiliary_device *mpfs_reset_adev_alloc(struct mpfs_clock_data *clk_data)
-{
-	struct auxiliary_device *adev;
-	int ret;
-
-	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
-	if (!adev)
-		return ERR_PTR(-ENOMEM);
-
-	adev->name = "reset-mpfs";
-	adev->dev.parent = clk_data->dev;
-	adev->dev.release = mpfs_reset_adev_release;
-	adev->id = 666u;
-
-	ret = auxiliary_device_init(adev);
-	if (ret) {
-		kfree(adev);
-		return ERR_PTR(ret);
-	}
-
-	return adev;
-}
-
-static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
-{
-	struct auxiliary_device *adev;
-	int ret;
-
-	adev = mpfs_reset_adev_alloc(clk_data);
-	if (IS_ERR(adev))
-		return PTR_ERR(adev);
-
-	ret = auxiliary_device_add(adev);
-	if (ret) {
-		auxiliary_device_uninit(adev);
-		return ret;
-	}
-
-	return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
-}
-
-#else /* !CONFIG_RESET_CONTROLLER */
-
-static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
-{
-	return 0;
-}
-
-#endif /* !CONFIG_RESET_CONTROLLER */
-
 static int mpfs_clk_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -499,7 +410,7 @@ static int mpfs_clk_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	return mpfs_reset_controller_register(clk_data);
+	return mpfs_reset_controller_register(dev, clk_data->base + REG_SUBBLK_RESET_CR);
 }
 
 static const struct of_device_id mpfs_clk_of_match_table[] = {
@@ -532,3 +443,4 @@ MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
 MODULE_AUTHOR("Padmarao Begari <[email protected]>");
 MODULE_AUTHOR("Daire McNamara <[email protected]>");
 MODULE_AUTHOR("Conor Dooley <[email protected]>");
+MODULE_IMPORT_NS(MCHP_CLK_MPFS);

drivers/reset/reset-mpfs.c

@@ -8,9 +8,11 @@
  */
 #include <linux/auxiliary_bus.h>
 #include <linux/delay.h>
+#include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/slab.h>
 #include <linux/reset-controller.h>
 #include <dt-bindings/clock/microchip,mpfs-clock.h>
 #include <soc/microchip/mpfs.h>
@@ -28,20 +30,30 @@
 /* block concurrent access to the soft reset register */
 static DEFINE_SPINLOCK(mpfs_reset_lock);
 
+struct mpfs_reset {
+	void __iomem *base;
+	struct reset_controller_dev rcdev;
+};
+
+static inline struct mpfs_reset *to_mpfs_reset(struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct mpfs_reset, rcdev);
+}
+
 /*
  * Peripheral clock resets
  */
-
 static int mpfs_assert(struct reset_controller_dev *rcdev, unsigned long id)
 {
+	struct mpfs_reset *rst = to_mpfs_reset(rcdev);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&mpfs_reset_lock, flags);
 
-	reg = mpfs_reset_read(rcdev->dev);
+	reg = readl(rst->base);
 	reg |= BIT(id);
-	mpfs_reset_write(rcdev->dev, reg);
+	writel(reg, rst->base);
 
 	spin_unlock_irqrestore(&mpfs_reset_lock, flags);
 
@@ -50,14 +62,15 @@ static int mpfs_assert(struct reset_controller_dev *rcdev, unsigned long id)
 
 static int mpfs_deassert(struct reset_controller_dev *rcdev, unsigned long id)
 {
+	struct mpfs_reset *rst = to_mpfs_reset(rcdev);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&mpfs_reset_lock, flags);
 
-	reg = mpfs_reset_read(rcdev->dev);
+	reg = readl(rst->base);
 	reg &= ~BIT(id);
-	mpfs_reset_write(rcdev->dev, reg);
+	writel(reg, rst->base);
 
 	spin_unlock_irqrestore(&mpfs_reset_lock, flags);
 
@@ -66,7 +79,8 @@ static int mpfs_deassert(struct reset_controller_dev *rcdev, unsigned long id)
 
 static int mpfs_status(struct reset_controller_dev *rcdev, unsigned long id)
 {
-	u32 reg = mpfs_reset_read(rcdev->dev);
+	struct mpfs_reset *rst = to_mpfs_reset(rcdev);
+	u32 reg = readl(rst->base);
 
 	/*
 	 * It is safe to return here as MPFS_NUM_RESETS makes sure the sign bit
@@ -121,11 +135,15 @@ static int mpfs_reset_probe(struct auxiliary_device *adev,
 {
 	struct device *dev = &adev->dev;
 	struct reset_controller_dev *rcdev;
+	struct mpfs_reset *rst;
 
-	rcdev = devm_kzalloc(dev, sizeof(*rcdev), GFP_KERNEL);
-	if (!rcdev)
+	rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL);
+	if (!rst)
 		return -ENOMEM;
 
+	rst->base = (void __iomem *)adev->dev.platform_data;
+
+	rcdev = &rst->rcdev;
 	rcdev->dev = dev;
 	rcdev->dev->parent = dev->parent;
 	rcdev->ops = &mpfs_reset_ops;
@@ -137,9 +155,68 @@ static int mpfs_reset_probe(struct auxiliary_device *adev,
 	return devm_reset_controller_register(dev, rcdev);
 }
 
+static void mpfs_reset_unregister_adev(void *_adev)
+{
+	struct auxiliary_device *adev = _adev;
+
+	auxiliary_device_delete(adev);
+	auxiliary_device_uninit(adev);
+}
+
+static void mpfs_reset_adev_release(struct device *dev)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+	kfree(adev);
+}
+
+static struct auxiliary_device *mpfs_reset_adev_alloc(struct device *clk_dev)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return ERR_PTR(-ENOMEM);
+
+	adev->name = "reset-mpfs";
+	adev->dev.parent = clk_dev;
+	adev->dev.release = mpfs_reset_adev_release;
+	adev->id = 666u;
+
+	ret = auxiliary_device_init(adev);
+	if (ret) {
+		kfree(adev);
+		return ERR_PTR(ret);
+	}
+
+	return adev;
+}
+
+int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = mpfs_reset_adev_alloc(clk_dev);
+	if (IS_ERR(adev))
+		return PTR_ERR(adev);
+
+	ret = auxiliary_device_add(adev);
+	if (ret) {
+		auxiliary_device_uninit(adev);
+		return ret;
+	}
+
+	adev->dev.platform_data = (__force void *)base;
+
+	return devm_add_action_or_reset(clk_dev, mpfs_reset_unregister_adev, adev);
+}
+EXPORT_SYMBOL_NS_GPL(mpfs_reset_controller_register, MCHP_CLK_MPFS);
+
 static const struct auxiliary_device_id mpfs_reset_ids[] = {
 	{
-		.name = "clk_mpfs.reset-mpfs",
+		.name = "reset_mpfs.reset-mpfs",
 	},
 	{ }
 };

include/soc/microchip/mpfs.h

@@ -43,11 +43,11 @@ struct mtd_info *mpfs_sys_controller_get_flash(struct mpfs_sys_controller *mpfs_
 #endif /* if IS_ENABLED(CONFIG_POLARFIRE_SOC_SYS_CTRL) */
 
 #if IS_ENABLED(CONFIG_MCHP_CLK_MPFS)
-
-u32 mpfs_reset_read(struct device *dev);
-
-void mpfs_reset_write(struct device *dev, u32 val);
-
+#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
+int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base);
+#else
+static inline int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base) { return 0; }
+#endif /* if IS_ENABLED(CONFIG_RESET_CONTROLLER) */
 #endif /* if IS_ENABLED(CONFIG_MCHP_CLK_MPFS) */
 
 #endif /* __SOC_MPFS_H__ */