[v2,4/7] soc: rockchip: add mfpwm driver

diff --git a/MAINTAINERS b/MAINTAINERS
index ed5cf56b3ebf9e3153cb9171908a1d36c246197d..39177b52be34d48967075b4f5983365725e9c055 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21424,6 +21424,8 @@  L:	linux-rockchip@lists.infradead.org
 L:	linux-pwm@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/pwm/rockchip,rk3576-pwm.yaml
+F:	drivers/soc/rockchip/mfpwm.c
+F:	include/soc/rockchip/mfpwm.h
 
 ROCKCHIP RK3568 RANDOM NUMBER GENERATOR SUPPORT
 M:	Daniel Golle <daniel@makrotopia.org>
diff --git a/drivers/soc/rockchip/Kconfig b/drivers/soc/rockchip/Kconfig
index 785f60c6f3ad1a09f517e69a69726a8178bed168..4e1e4926c514a5a2c4d4caf8cf9809a098badc7d 100644
--- a/drivers/soc/rockchip/Kconfig
+++ b/drivers/soc/rockchip/Kconfig
@@ -30,4 +30,17 @@  config ROCKCHIP_DTPM
 	  on this platform. That will create all the power capping capable
 	  devices.
 
+config ROCKCHIP_MFPWM
+	tristate "Rockchip multi-function PWM controller"
+	depends on OF
+	depends on HAS_IOMEM
+	help
+	  Some Rockchip SoCs, such as the RK3576, use a PWM controller that has
+	  several different functions, such as generating PWM waveforms but also
+	  counting waveforms.
+
+	  This driver manages the overall device, and selects between different
+	  functionalities at runtime as needed, with drivers for them
+	  implemented in their respective subsystems.
+
 endif
diff --git a/drivers/soc/rockchip/Makefile b/drivers/soc/rockchip/Makefile
index 23d414433c8c58557effc214337ec8e6ff17a461..ba12dbd01ac794910d9407c268e89071cd2b3139 100644
--- a/drivers/soc/rockchip/Makefile
+++ b/drivers/soc/rockchip/Makefile
@@ -5,3 +5,4 @@ 
 obj-$(CONFIG_ROCKCHIP_GRF) += grf.o
 obj-$(CONFIG_ROCKCHIP_IODOMAIN) += io-domain.o
 obj-$(CONFIG_ROCKCHIP_DTPM) += dtpm.o
+obj-$(CONFIG_ROCKCHIP_MFPWM) += mfpwm.o
diff --git a/drivers/soc/rockchip/mfpwm.c b/drivers/soc/rockchip/mfpwm.c
new file mode 100644
index 0000000000000000000000000000000000000000..e68d8e71cc590e7ced324cdde7ac79a4b01cae3d
--- /dev/null
+++ b/drivers/soc/rockchip/mfpwm.c
@@ -0,0 +1,398 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2025 Collabora Ltd.
+ *
+ * A driver to manage all the different functionalities exposed by Rockchip's
+ * PWMv4 hardware.
+ *
+ * This driver is chiefly focused on guaranteeing non-concurrent operation
+ * between the different device functions, as well as setting the clocks.
+ * It registers the device function platform devices, e.g. PWM output or
+ * PWM capture.
+ *
+ * Authors:
+ *     Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
+ */
+
+#include <linux/array_size.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <soc/rockchip/mfpwm.h>
+
+/**
+ * struct rockchip_mfpwm - private mfpwm driver instance state struct
+ * @pdev: pointer to this instance's &struct platform_device
+ * @base: pointer to the memory mapped registers of this device
+ * @pwm_clk: pointer to the PLL clock the PWM signal may be derived from
+ * @osc_clk: pointer to the fixed crystal the PWM signal may be derived from
+ * @rc_clk: pointer to the RC oscillator the PWM signal may be derived from
+ * @chosen_clk: a clk-mux of pwm_clk, osc_clk and rc_clk
+ * @pclk: pointer to the APB bus clock needed for mmio register access
+ * @pwm_dev: pointer to the &struct platform_device of the pwm output driver
+ * @counter_dev: pointer to the &struct platform_device of the counter driver
+ * @active_func: pointer to the currently active device function, or %NULL if no
+ *              device function is currently actively using any of the shared
+ *              resources. May only be checked/modified with @state_lock held.
+ * @acquire_cnt: number of times @active_func has currently mfpwm_acquire()'d
+ *               it. Must only be checked or modified while holding @state_lock.
+ * @state_lock: this lock is held while either the active device function, the
+ *              enable register, or the chosen clock is being changed.
+ * @irq: the IRQ number of this device
+ */
+struct rockchip_mfpwm {
+	struct platform_device *pdev;
+	void __iomem *base;
+	struct clk *pwm_clk;
+	struct clk *osc_clk;
+	struct clk *rc_clk;
+	struct clk *chosen_clk;
+	struct clk *pclk;
+	struct platform_device *pwm_dev;
+	struct platform_device *counter_dev;
+	struct rockchip_mfpwm_func *active_func;
+	unsigned int acquire_cnt;
+	spinlock_t state_lock;
+	int irq;
+};
+
+static atomic_t subdev_id = ATOMIC_INIT(0);
+
+static inline struct rockchip_mfpwm *to_rockchip_mfpwm(struct platform_device *pdev)
+{
+	return platform_get_drvdata(pdev);
+}
+
+static int mfpwm_check_pwmf(const struct rockchip_mfpwm_func *pwmf,
+			    const char *fname)
+{
+	struct device *dev = &pwmf->parent->pdev->dev;
+
+	if (IS_ERR_OR_NULL(pwmf)) {
+		dev_warn(dev, "called %s with an erroneous handle, no effect\n",
+			 fname);
+		return -EINVAL;
+	}
+
+	if (IS_ERR_OR_NULL(pwmf->parent)) {
+		dev_warn(dev, "called %s with an erroneous mfpwm_func parent, no effect\n",
+			 fname);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+__attribute__((nonnull))
+static bool mfpwm_pwmf_is_active_pwmf(const struct rockchip_mfpwm_func *pwmf)
+{
+	if (pwmf->parent->active_func) {
+		if (pwmf->parent->active_func->id == pwmf->id)
+			return true;
+	}
+
+	return false;
+}
+
+__attribute__((nonnull))
+static int mfpwm_do_acquire(struct rockchip_mfpwm_func *pwmf)
+{
+	struct rockchip_mfpwm *mfpwm = pwmf->parent;
+	unsigned int cnt;
+
+	if (mfpwm->active_func && pwmf->id != mfpwm->active_func->id)
+		return -EBUSY;
+
+	if (!mfpwm->active_func)
+		mfpwm->active_func = pwmf;
+
+	if (!check_add_overflow(mfpwm->acquire_cnt, 1, &cnt)) {
+		mfpwm->acquire_cnt = cnt;
+	} else {
+		dev_warn(&mfpwm->pdev->dev, "prevented acquire counter overflow in %s\n",
+			 __func__);
+		return -EOVERFLOW;
+	}
+
+	dev_dbg(&mfpwm->pdev->dev, "%d acquired mfpwm, acquires now at %u\n",
+		pwmf->id, mfpwm->acquire_cnt);
+
+	return clk_enable(mfpwm->pclk);
+}
+
+int mfpwm_acquire(struct rockchip_mfpwm_func *pwmf)
+{
+	struct rockchip_mfpwm *mfpwm;
+	unsigned long flags;
+	int ret = 0;
+
+	ret = mfpwm_check_pwmf(pwmf, "mfpwm_acquire");
+	if (ret)
+		return ret;
+
+	mfpwm = pwmf->parent;
+	dev_dbg(&mfpwm->pdev->dev, "%d is attempting to acquire\n", pwmf->id);
+
+	if (!spin_trylock_irqsave(&mfpwm->state_lock, flags))
+		return -EBUSY;
+
+	ret = mfpwm_do_acquire(pwmf);
+
+	spin_unlock_irqrestore(&mfpwm->state_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(mfpwm_acquire, "ROCKCHIP_MFPWM");
+
+__attribute__((nonnull))
+static void mfpwm_do_release(const struct rockchip_mfpwm_func *pwmf)
+{
+	struct rockchip_mfpwm *mfpwm = pwmf->parent;
+
+	if (!mfpwm->active_func)
+		return;
+
+	if (mfpwm->active_func->id != pwmf->id)
+		return;
+
+	/*
+	 * No need to check_sub_overflow here, !mfpwm->active_func above catches
+	 * this type of problem already.
+	 */
+	mfpwm->acquire_cnt--;
+
+	if (!mfpwm->acquire_cnt)
+		mfpwm->active_func = NULL;
+
+	clk_disable(mfpwm->pclk);
+}
+
+void mfpwm_release(const struct rockchip_mfpwm_func *pwmf)
+{
+	struct rockchip_mfpwm *mfpwm;
+	unsigned long flags;
+
+	if (mfpwm_check_pwmf(pwmf, "mfpwm_release"))
+		return;
+
+	mfpwm = pwmf->parent;
+
+	spin_lock_irqsave(&mfpwm->state_lock, flags);
+	mfpwm_do_release(pwmf);
+	dev_dbg(&mfpwm->pdev->dev, "%d released mfpwm, acquires now at %u\n",
+		pwmf->id, mfpwm->acquire_cnt);
+	spin_unlock_irqrestore(&mfpwm->state_lock, flags);
+}
+EXPORT_SYMBOL_NS_GPL(mfpwm_release, "ROCKCHIP_MFPWM");
+
+void mfpwm_remove_func(struct rockchip_mfpwm_func *pwmf)
+{
+	struct rockchip_mfpwm *mfpwm;
+	unsigned long flags;
+
+	if (mfpwm_check_pwmf(pwmf, "mfpwm_remove_func"))
+		return;
+
+	mfpwm = pwmf->parent;
+	spin_lock_irqsave(&mfpwm->state_lock, flags);
+
+	if (mfpwm_pwmf_is_active_pwmf(pwmf)) {
+		dev_dbg(&mfpwm->pdev->dev, "removing active function %d\n",
+			pwmf->id);
+
+		while (mfpwm->acquire_cnt > 0)
+			mfpwm_do_release(pwmf);
+
+		mfpwm_reg_write(mfpwm->base, PWMV4_REG_ENABLE,
+				PWMV4_EN(false) | PWMV4_CLK_EN(false));
+	}
+
+	if (mfpwm->pwm_dev && mfpwm->pwm_dev->id == pwmf->id) {
+		dev_dbg(&mfpwm->pdev->dev, "clearing pwm_dev pointer\n");
+		mfpwm->pwm_dev = NULL;
+	} else if (mfpwm->counter_dev && mfpwm->counter_dev->id == pwmf->id) {
+		dev_dbg(&mfpwm->pdev->dev, "clearing counter_dev pointer\n");
+		mfpwm->counter_dev = NULL;
+	} else {
+		dev_warn(&mfpwm->pdev->dev, "trying to remove an unknown mfpwm device function");
+	}
+
+	spin_unlock_irqrestore(&mfpwm->state_lock, flags);
+}
+EXPORT_SYMBOL_NS_GPL(mfpwm_remove_func, "ROCKCHIP_MFPWM");
+
+/**
+ * mfpwm_register_subdev - register a single mfpwm_func
+ * @mfpwm: pointer to the parent &struct rockchip_mfpwm
+ * @target: pointer to where the &struct platform_device pointer should be
+ *          stored, usually a member of @mfpwm
+ * @name: sub-device name string
+ *
+ * Allocate a single &struct mfpwm_func, fill its members with appropriate data,
+ * and register a new platform device, saving its pointer to @target. The
+ * allocation is devres tracked, so will be automatically freed on mfpwm remove.
+ *
+ * Returns: 0 on success, negative errno on error
+ */
+static int mfpwm_register_subdev(struct rockchip_mfpwm *mfpwm,
+				 struct platform_device **target,
+				 const char *name)
+{
+	struct rockchip_mfpwm_func *func;
+	struct platform_device *child;
+
+	func = devm_kzalloc(&mfpwm->pdev->dev, sizeof(*func), GFP_KERNEL);
+	if (IS_ERR(func))
+		return PTR_ERR(func);
+	func->irq = mfpwm->irq;
+	func->parent = mfpwm;
+	func->id = atomic_inc_return(&subdev_id);
+	func->base = mfpwm->base;
+	func->core = mfpwm->chosen_clk;
+	child = platform_device_register_data(&mfpwm->pdev->dev, name, func->id,
+					      func, sizeof(*func));
+
+	if (IS_ERR(child))
+		return PTR_ERR(child);
+
+	*target = child;
+
+	return 0;
+}
+
+static int mfpwm_register_subdevs(struct rockchip_mfpwm *mfpwm)
+{
+	int ret;
+
+	ret = mfpwm_register_subdev(mfpwm, &mfpwm->pwm_dev, "pwm-rockchip-v4");
+	if (ret)
+		return ret;
+
+	ret = mfpwm_register_subdev(mfpwm, &mfpwm->counter_dev,
+				    "rockchip-pwm-capture");
+	if (ret)
+		goto err_unreg_pwm_dev;
+
+	return 0;
+
+err_unreg_pwm_dev:
+	platform_device_unregister(mfpwm->pwm_dev);
+
+	return ret;
+}
+
+static int rockchip_mfpwm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rockchip_mfpwm *mfpwm;
+	char *clk_mux_name;
+	const char *mux_p_names[3];
+	int ret = 0;
+
+	mfpwm = devm_kzalloc(&pdev->dev, sizeof(*mfpwm), GFP_KERNEL);
+	if (IS_ERR(mfpwm))
+		return PTR_ERR(mfpwm);
+
+	mfpwm->pdev = pdev;
+
+	spin_lock_init(&mfpwm->state_lock);
+
+	mfpwm->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(mfpwm->base))
+		return dev_err_probe(dev, PTR_ERR(mfpwm->base),
+				     "failed to ioremap address\n");
+
+	mfpwm->pclk = devm_clk_get_prepared(dev, "pclk");
+	if (IS_ERR(mfpwm->pclk))
+		return dev_err_probe(dev, PTR_ERR(mfpwm->pclk),
+				     "couldn't get and prepare 'pclk' clock\n");
+
+	mfpwm->irq = platform_get_irq(pdev, 0);
+	if (mfpwm->irq < 0)
+		return dev_err_probe(dev, mfpwm->irq, "couldn't get irq 0\n");
+
+	mfpwm->pwm_clk = devm_clk_get_prepared(dev, "pwm");
+	if (IS_ERR(mfpwm->pwm_clk))
+		return dev_err_probe(dev, PTR_ERR(mfpwm->pwm_clk),
+				     "couldn't get and prepare 'pwm' clock\n");
+
+	mfpwm->osc_clk = devm_clk_get_prepared(dev, "osc");
+	if (IS_ERR(mfpwm->osc_clk))
+		return dev_err_probe(dev, PTR_ERR(mfpwm->osc_clk),
+				     "couldn't get and prepare 'osc' clock\n");
+
+	mfpwm->rc_clk = devm_clk_get_prepared(dev, "rc");
+	if (IS_ERR(mfpwm->rc_clk))
+		return dev_err_probe(dev, PTR_ERR(mfpwm->rc_clk),
+				     "couldn't get and prepare 'rc' clock\n");
+
+	clk_mux_name = devm_kasprintf(dev, GFP_KERNEL, "%s_chosen", dev_name(dev));
+	if (!clk_mux_name)
+		return -ENOMEM;
+
+	mux_p_names[0] = __clk_get_name(mfpwm->pwm_clk);
+	mux_p_names[1] = __clk_get_name(mfpwm->osc_clk);
+	mux_p_names[2] = __clk_get_name(mfpwm->rc_clk);
+	mfpwm->chosen_clk = clk_register_mux(dev, clk_mux_name, mux_p_names,
+					     ARRAY_SIZE(mux_p_names),
+					     CLK_SET_RATE_PARENT,
+					     mfpwm->base + PWMV4_REG_CLK_CTRL,
+					     PWMV4_CLK_SRC_SHIFT, PWMV4_CLK_SRC_WIDTH,
+					     CLK_MUX_HIWORD_MASK, NULL);
+	ret = clk_prepare(mfpwm->chosen_clk);
+	if (ret) {
+		dev_err(dev, "failed to prepare PWM clock mux: %pe\n",
+			ERR_PTR(ret));
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, mfpwm);
+
+	ret = mfpwm_register_subdevs(mfpwm);
+	if (ret) {
+		dev_err(dev, "failed to register sub-devices: %pe\n",
+			ERR_PTR(ret));
+		return ret;
+	}
+
+	return ret;
+}
+
+static void rockchip_mfpwm_remove(struct platform_device *pdev)
+{
+	struct rockchip_mfpwm *mfpwm = to_rockchip_mfpwm(pdev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&mfpwm->state_lock, flags);
+
+	if (mfpwm->chosen_clk)
+		clk_unregister_mux(mfpwm->chosen_clk);
+
+	spin_unlock_irqrestore(&mfpwm->state_lock, flags);
+}
+
+static const struct of_device_id rockchip_mfpwm_of_match[] = {
+	{
+		.compatible = "rockchip,rk3576-pwm",
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rockchip_mfpwm_of_match);
+
+static struct platform_driver rockchip_mfpwm_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = rockchip_mfpwm_of_match,
+	},
+	.probe = rockchip_mfpwm_probe,
+	.remove = rockchip_mfpwm_remove,
+};
+module_platform_driver(rockchip_mfpwm_driver);
+
+MODULE_AUTHOR("Nicolas Frattaroli <nicolas.frattaroli@collabora.com>");
+MODULE_DESCRIPTION("Rockchip MFPWM Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/soc/rockchip/mfpwm.h b/include/soc/rockchip/mfpwm.h
new file mode 100644
index 0000000000000000000000000000000000000000..05fc63ffb2f3155e13b254fc1492de77d03ff087
--- /dev/null
+++ b/include/soc/rockchip/mfpwm.h
@@ -0,0 +1,484 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2025 Collabora Ltd.
+ *
+ * Common header file for all the Rockchip Multi-function PWM controller
+ * drivers that are spread across subsystems.
+ *
+ * Authors:
+ *     Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
+ */
+
+#ifndef __SOC_ROCKCHIP_MFPWM_H__
+#define __SOC_ROCKCHIP_MFPWM_H__
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+
+struct rockchip_mfpwm;
+
+/**
+ * struct rockchip_mfpwm_func - struct representing a single function driver
+ *
+ * @id: unique id for this function driver instance
+ * @base: pointer to start of MMIO registers
+ * @parent: a pointer to the parent mfpwm struct
+ * @irq: the shared IRQ gotten from the parent mfpwm device
+ * @core: a pointer to the clk mux that drives this channel's PWM
+ */
+struct rockchip_mfpwm_func {
+	int id;
+	void __iomem *base;
+	struct rockchip_mfpwm *parent;
+	int irq;
+	struct clk *core;
+};
+
+/*
+ * PWMV4 Register Definitions
+ * --------------------------
+ *
+ * Attributes:
+ *  RW  - Read-Write
+ *  RO  - Read-Only
+ *  WO  - Write-Only
+ *  W1T - Write high, Self-clearing
+ *  W1C - Write high to clear interrupt
+ *
+ * Bit ranges to be understood with Verilog-like semantics,
+ * e.g. [03:00] is 4 bits: 0, 1, 2 and 3.
+ *
+ * All registers must be accessed with 32-bit width accesses only
+ */
+
+#define PWMV4_REG_VERSION		0x000
+/*
+ * VERSION Register Description
+ * [31:24] RO  | Hardware Major Version
+ * [23:16] RO  | Hardware Minor Version			docArrive
+ * [15:15] RO  | Reserved
+ * [14:14] RO  | Hardware supports biphasic counters
+ * [13:13] RO  | Hardware supports filters
+ * [12:12] RO  | Hardware supports waveform generation
+ * [11:11] RO  | Hardware supports counter
+ * [10:10] RO  | Hardware supports frequency metering
+ * [09:09] RO  | Hardware supports power key functionality
+ * [08:08] RO  | Hardware supports infrared transmissions
+ * [07:04] RO  | Channel index of this instance
+ * [03:00] RO  | Number of channels the base instance supports
+ */
+static inline __pure u32 rockchip_pwm_v4_ver_chn_num(u32 val)
+{
+	return (val & GENMASK(3, 0));
+}
+
+static inline __pure u32 rockchip_pwm_v4_ver_chn_idx(u32 val)
+{
+	return (val & GENMASK(7, 4)) >> 4;
+}
+
+static inline __pure u32 rockchip_pwm_v4_ver_major(u32 val)
+{
+	return (val & GENMASK(31, 24)) >> 24;
+}
+
+static inline __pure u32 rockchip_pwm_v4_ver_minor(u32 val)
+{
+	return (val & GENMASK(23, 16)) >> 16;
+}
+
+#define PWMV4_REG_ENABLE		0x004
+/*
+ * ENABLE Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:06] RO  | Reserved
+ * [05:05] RW  | PWM Channel Counter Read Enable, 1 = enabled
+ */
+#define PWMV4_CHN_CNT_RD_EN(v)		FIELD_PREP_HI16_WE(BIT(5), (v))
+/*
+ * [04:04] W1T | PWM Globally Joined Control Enable
+ *               1 = this PWM channel will be enabled by a global pwm enable
+ *               bit instead of the PWM Enable bit.
+ */
+#define PWMV4_GLOBAL_CTRL_EN(v)		FIELD_PREP_HI16_WE(BIT(4), (v))
+/*
+ * [03:03] RW  | Force Clock Enable
+ *               0 = disabled, if the PWM channel is inactive then so is the
+ *               clock prescale module
+ */
+#define PWMV4_FORCE_CLK_EN(v)		FIELD_PREP_HI16_WE(BIT(3), (v))
+/*
+ * [02:02] W1T | PWM Control Update Enable
+ *               1 = enabled, commits modifications of _CTRL, _PERIOD, _DUTY and
+ *               _OFFSET registers once 1 is written to it
+ */
+#define PWMV4_CTRL_UPDATE_EN		FIELD_PREP_HI16_WE_CONST(BIT(2), 1)
+/*
+ * [01:01] RW  | PWM Enable, 1 = enabled
+ *               If in one-shot mode, clears after end of operation
+ */
+#define PWMV4_EN_MASK			BIT(1)
+#define PWMV4_EN(v)			FIELD_PREP_HI16_WE(PWMV4_EN_MASK, \
+							   ((v) ? 1 : 0))
+/*
+ * [00:00] RW  | PWM Clock Enable, 1 = enabled
+ *               If in one-shot mode, clears after end of operation
+ */
+#define PWMV4_CLK_EN_MASK		BIT(0)
+#define PWMV4_CLK_EN(v)			FIELD_PREP_HI16_WE(PWMV4_CLK_EN_MASK, \
+							   ((v) ? 1 : 0))
+#define PWMV4_EN_BOTH_MASK		(PWMV4_EN_MASK | PWMV4_CLK_EN_MASK)
+static inline __pure bool rockchip_pwm_v4_is_enabled(unsigned int val)
+{
+	return (val & PWMV4_EN_BOTH_MASK);
+}
+
+#define PWMV4_REG_CLK_CTRL		0x008
+/*
+ * CLK_CTRL Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:15] RW  | Clock Global Selection
+ *               0 = current channel scale clock
+ *               1 = global channel scale clock
+ */
+#define PWMV4_CLK_GLOBAL(v)		FIELD_PREP_HI16_WE(BIT(15), (v))
+/*
+ * [14:13] RW  | Clock Source Selection
+ *               0 = Clock from PLL, frequency can be configured
+ *               1 = Clock from crystal oscillator, frequency is fixed
+ *               2 = Clock from RC oscillator, frequency is fixed
+ *               3 = Reserved
+ *               NOTE: The purpose for this clock-mux-outside-CRU construct is
+ *                     to let the SoC go into a sleep state with the PWM
+ *                     hardware still having a clock signal for IR input, which
+ *                     can then wake up the SoC.
+ */
+#define PWMV4_CLK_SRC_PLL		0x0U
+#define PWMV4_CLK_SRC_CRYSTAL		0x1U
+#define PWMV4_CLK_SRC_RC		0x2U
+#define PWMV4_CLK_SRC_SHIFT		13
+#define PWMV4_CLK_SRC_WIDTH		2
+/*
+ * [12:04] RW  | Scale Factor to apply to pre-scaled clock
+ *               1 <= v <= 256, v means clock divided by 2*v
+ */
+#define PWMV4_CLK_SCALE_F(v)		FIELD_PREP_HI16_WE(GENMASK(12, 4), (v))
+/*
+ * [03:03] RO  | Reserved
+ * [02:00] RW  | Prescale Factor
+ *               v here means the input clock is divided by pow(2, v)
+ */
+#define PWMV4_CLK_PRESCALE_F(v)		FIELD_PREP_HI16_WE(GENMASK(2, 0), (v))
+
+#define PWMV4_REG_CTRL			0x00C
+/*
+ * CTRL Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:09] RO  | Reserved
+ * [08:06] RW  | PWM Input Channel Selection
+ *               By default, the channel selects its own input, but writing v
+ *               here selects PWM input from channel v instead.
+ */
+#define PWMV4_CTRL_IN_SEL(v)		FIELD_PREP_HI16_WE(GENMASK(8, 6), (v))
+/* [05:05] RW  | Aligned Mode, 0 = Valid, 1 = Invalid */
+#define PWMV4_CTRL_UNALIGNED(v)		FIELD_PREP_HI16_WE(BIT(5), (v))
+/* [04:04] RW  | Output Mode, 0 = Left Aligned, 1 = Centre Aligned */
+#define PWMV4_LEFT_ALIGNED		0x0U
+#define PWMV4_CENTRE_ALIGNED		0x1U
+#define PWMV4_CTRL_OUT_MODE(v)		FIELD_PREP_HI16_WE(BIT(4), (v))
+/*
+ * [03:03] RW  | Inactive Polarity for when the channel is either disabled or
+ *               has completed outputting the entire waveform in one-shot mode.
+ *               0 = Negative, 1 = Positive
+ */
+#define PWMV4_POLARITY_N		0x0U
+#define PWMV4_POLARITY_P		0x1U
+#define PWMV4_INACTIVE_POL(v)		FIELD_PREP_HI16_WE(BIT(3), (v))
+/*
+ * [02:02] RW  | Duty Cycle Polarity to use at the start of the waveform.
+ *               0 = Negative, 1 = Positive
+ */
+#define PWMV4_DUTY_POL_SHIFT		2
+#define PWMV4_DUTY_POL_MASK		BIT(PWMV4_DUTY_POL_SHIFT)
+#define PWMV4_DUTY_POL(v)		FIELD_PREP_HI16_WE(PWMV4_DUTY_POL_MASK, \
+							   (v))
+/*
+ * [01:00] RW  | PWM Mode
+ *               0 = One-shot mode, PWM generates waveform RPT times
+ *               1 = Continuous mode
+ *               2 = Capture mode, PWM measures cycles of input waveform
+ *               3 = Reserved
+ */
+#define PWMV4_MODE_ONESHOT		0x0U
+#define PWMV4_MODE_CONT			0x1U
+#define PWMV4_MODE_CAPTURE		0x2U
+#define PWMV4_MODE_MASK			GENMASK(1, 0)
+#define PWMV4_MODE(v)			FIELD_PREP_HI16_WE(PWMV4_MODE_MASK, (v))
+#define PWMV4_CTRL_COM_FLAGS	(PWMV4_INACTIVE_POL(PWMV4_POLARITY_N) | \
+				 PWMV4_DUTY_POL(PWMV4_POLARITY_P) | \
+				 PWMV4_CTRL_OUT_MODE(PWMV4_LEFT_ALIGNED) | \
+				 PWMV4_CTRL_UNALIGNED(true))
+#define PWMV4_CTRL_CONT_FLAGS	(PWMV4_MODE(PWMV4_MODE_CONT) | \
+				 PWMV4_CTRL_COM_FLAGS)
+#define PWMV4_CTRL_CAP_FLAGS	(PWMV4_MODE(PWMV4_MODE_CAPTURE) | \
+				 PWMV4_CTRL_COM_FLAGS)
+
+#define PWMV4_REG_PERIOD		0x010
+/*
+ * PERIOD Register Description
+ * [31:00] RW  | Period of the output waveform
+ *               Constraints: should be even if CTRL_OUT_MODE is CENTRE_ALIGNED
+ */
+
+#define PWMV4_REG_DUTY			0x014
+/*
+ * DUTY Register Description
+ * [31:00] RW  | Duty cycle of the output waveform
+ *               Constraints: should be even if CTRL_OUT_MODE is CENTRE_ALIGNED
+ */
+
+#define PWMV4_REG_OFFSET		0x018
+/*
+ * OFFSET Register Description
+ * [31:00] RW  | Offset of the output waveform, based on the PWM clock
+ *               Constraints: 0 <= v <= (PERIOD - DUTY)
+ */
+
+#define PWMV4_REG_RPT			0x01C
+/*
+ * RPT Register Description
+ * [31:16] RW  | Second dimensional of the effective number of waveform
+ *               repetitions. Increases by one every first dimensional times.
+ *               Value `n` means `n + 1` repetitions. The final number of
+ *               repetitions of the waveform in one-shot mode is:
+ *               `(first_dimensional + 1) * (second_dimensional + 1)`
+ * [15:00] RW  | First dimensional of the effective number of waveform
+ *               repetitions. Value `n` means `n + 1` repetitions.
+ */
+
+#define PWMV4_REG_FILTER_CTRL		0x020
+/*
+ * FILTER_CTRL Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:10] RO  | Reserved
+ * [09:04] RW  | Filter window number
+ * [03:01] RO  | Reserved
+ * [00:00] RW  | Filter Enable, 0 = disabled, 1 = enabled
+ */
+
+#define PWMV4_REG_CNT			0x024
+/*
+ * CNT Register Description
+ * [31:00] RO  | Current value of the PWM Channel 0 counter in pwm clock cycles,
+ *               0 <= v <= 2^32-1
+ */
+
+#define PWMV4_REG_ENABLE_DELAY		0x028
+/*
+ * ENABLE_DELAY Register Description
+ * [31:16] RO  | Reserved
+ * [15:00] RW  | PWM enable delay, in an unknown unit but probably cycles
+ */
+
+#define PWMV4_REG_HPC			0x02C
+/*
+ * HPC Register Description
+ * [31:00] RW  | Number of effective high polarity cycles of the input waveform
+ *               in capture mode. Based on the PWM clock. 0 <= v <= 2^32-1
+ */
+
+#define PWMV4_REG_LPC			0x030
+/*
+ * LPC Register Description
+ * [31:00] RW  | Number of effective low polarity cycles of the input waveform
+ *               in capture mode. Based on the PWM clock. 0 <= v <= 2^32-1
+ */
+
+#define PWMV4_REG_BIPHASIC_CNT_CTRL0	0x040
+/*
+ * BIPHASIC_CNT_CTRL0 Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:10] RO  | Reserved
+ * [09:09] RW  | Biphasic Counter Phase Edge Selection for mode 0,
+ *               0 = rising edge (posedge), 1 = falling edge (negedge)
+ * [08:08] RW  | Biphasic Counter Clock force enable, 1 = force enable
+ * [07:07] W1T | Synchronous Enable
+ * [06:06] W1T | Mode Switch
+ *               0 = Normal Mode, 1 = Switch timer clock and measured clock
+ *               Constraints: "Biphasic Counter Mode" must be 0 if this is 1
+ * [05:03] RW  | Biphasic Counter Mode
+ *               0x0 = Mode 0, 0x1 = Mode 1, 0x2 = Mode 2, 0x3 = Mode 3,
+ *               0x4 = Mode 4, 0x5 = Reserved
+ * [02:02] RW  | Biphasic Counter Clock Selection
+ *               0 = clock is from PLL and frequency can be configured
+ *               1 = clock is from crystal oscillator and frequency is fixed
+ * [01:01] RW  | Biphasic Counter Continuous Mode
+ * [00:00] W1T | Biphasic Counter Enable
+ */
+
+#define PWMV4_REG_BIPHASIC_CNT_CTRL1	0x044
+/*
+ * BIPHASIC_CNT_CTRL1 Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:11] RO  | Reserved
+ * [10:04] RW  | Biphasic Counter Filter Window Number
+ * [03:01] RO  | Reserved
+ * [00:00] RW  | Biphasic Counter Filter Enable
+ */
+
+#define PWMV4_REG_BIPHASIC_CNT_TIMER	0x048
+/*
+ * BIPHASIC_CNT_TIMER Register Description
+ * [31:00] RW  | Biphasic Counter Timer Value, in number of biphasic counter
+ *               timer clock cycles
+ */
+
+#define PWMV4_REG_BIPHASIC_CNT_RES	0x04C
+/*
+ * BIPHASIC_CNT_RES Register Description
+ * [31:00] RO  | Biphasic Counter Result Value
+ *               Constraints: Can only be read after INTSTS[9] is asserted
+ */
+
+#define PWMV4_REG_BIPHASIC_CNT_RES_S	0x050
+/*
+ * BIPHASIC_CNT_RES_S Register Description
+ * [31:00] RO  | Biphasic Counter Result Value with synchronised processing
+ *               Can be read in real-time if BIPHASIC_CNT_CTRL0[7] was set to 1
+ */
+
+#define PWMV4_REG_INTSTS		0x070
+/*
+ * INTSTS Register Description
+ * [31:10] RO  | Reserved
+ * [09:09] W1C | Biphasic Counter Interrupt Status, 1 = interrupt asserted
+ * [08:08] W1C | Waveform Middle Interrupt Status, 1 = interrupt asserted
+ * [07:07] W1C | Waveform Max Interrupt Status, 1 = interrupt asserted
+ * [06:06] W1C | IR Transmission End Interrupt Status, 1 = interrupt asserted
+ * [05:05] W1C | Power Key Match Interrupt Status, 1 = interrupt asserted
+ * [04:04] W1C | Frequency Meter Interrupt Status, 1 = interrupt asserted
+ * [03:03] W1C | Reload Interrupt Status, 1 = interrupt asserted
+ * [02:02] W1C | Oneshot End Interrupt Status, 1 = interrupt asserted
+ * [01:01] W1C | HPC Capture Interrupt Status, 1 = interrupt asserted
+ * [00:00] W1C | LPC Capture Interrupt Status, 1 = interrupt asserted
+ */
+#define PWMV4_INT_LPC			BIT(0)
+#define PWMV4_INT_HPC			BIT(1)
+#define PWMV4_INT_LPC_W(v)		FIELD_PREP_HI16_WE(PWMV4_INT_LPC, \
+							   ((v) ? 1 : 0))
+#define PWMV4_INT_HPC_W(v)		FIELD_PREP_HI16_WE(PWMV4_INT_HPC, \
+							   ((v) ? 1 : 0))
+
+#define PWMV4_REG_INT_EN		0x074
+/*
+ * INT_EN Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:10] RO  | Reserved
+ * [09:09] RW  | Biphasic Counter Interrupt Enable, 1 = enabled
+ * [08:08] W1C | Waveform Middle Interrupt Enable, 1 = enabled
+ * [07:07] W1C | Waveform Max Interrupt Enable, 1 = enabled
+ * [06:06] W1C | IR Transmission End Interrupt Enable, 1 = enabled
+ * [05:05] W1C | Power Key Match Interrupt Enable, 1 = enabled
+ * [04:04] W1C | Frequency Meter Interrupt Enable, 1 = enabled
+ * [03:03] W1C | Reload Interrupt Enable, 1 = enabled
+ * [02:02] W1C | Oneshot End Interrupt Enable, 1 = enabled
+ * [01:01] W1C | HPC Capture Interrupt Enable, 1 = enabled
+ * [00:00] W1C | LPC Capture Interrupt Enable, 1 = enabled
+ */
+
+#define PWMV4_REG_INT_MASK		0x078
+/*
+ * INT_MASK Register Description
+ * [31:16] WO  | Write Enable Mask for the lower half of the register
+ *               Set bit `n` here to 1 if you wish to modify bit `n >> 16` in
+ *               the same write operation
+ * [15:10] RO  | Reserved
+ * [09:09] RW  | Biphasic Counter Interrupt Masked, 1 = masked
+ * [08:08] W1C | Waveform Middle Interrupt Masked, 1 = masked
+ * [07:07] W1C | Waveform Max Interrupt Masked, 1 = masked
+ * [06:06] W1C | IR Transmission End Interrupt Masked, 1 = masked
+ * [05:05] W1C | Power Key Match Interrupt Masked, 1 = masked
+ * [04:04] W1C | Frequency Meter Interrupt Masked, 1 = masked
+ * [03:03] W1C | Reload Interrupt Masked, 1 = masked
+ * [02:02] W1C | Oneshot End Interrupt Masked, 1 = masked
+ * [01:01] W1C | HPC Capture Interrupt Masked, 1 = masked
+ * [00:00] W1C | LPC Capture Interrupt Masked, 1 = masked
+ */
+
+static inline u32 mfpwm_reg_read(void __iomem *base, u32 reg)
+{
+	return readl(base + reg);
+}
+
+static inline void mfpwm_reg_write(void __iomem *base, u32 reg, u32 val)
+{
+	writel(val, base + reg);
+}
+
+/**
+ * mfpwm_acquire - try becoming the active mfpwm function device
+ * @pwmf: pointer to the calling driver instance's &struct rockchip_mfpwm_func
+ *
+ * mfpwm device "function" drivers must call this function before doing anything
+ * that either modifies or relies on the parent device's state, such as clocks,
+ * enabling/disabling outputs, modifying shared regs etc.
+ *
+ * The return statues should always be checked.
+ *
+ * All mfpwm_acquire() calls must be balanced with corresponding mfpwm_release()
+ * calls once the device is no longer making changes that affect other devices,
+ * or stops producing user-visible effects that depend on the current device
+ * state being kept as-is. (e.g. after the PWM output signal is stopped)
+ *
+ * The same device function may mfpwm_acquire() multiple times while it already
+ * is active, i.e. it is re-entrant, though it needs to balance this with the
+ * same number of mfpwm_release() calls.
+ *
+ * Context: This function does not sleep.
+ *
+ * Return:
+ * * %0                 - success
+ * * %-EBUSY            - a different device function is active
+ * * %-EOVERFLOW        - the acquire counter is at its maximum
+ */
+int __must_check mfpwm_acquire(struct rockchip_mfpwm_func *pwmf);
+
+/**
+ * mfpwm_release - drop usage of active mfpwm device function by 1
+ * @pwmf: pointer to the calling driver instance's &struct rockchip_mfpwm_func
+ *
+ * This is the balancing call to mfpwm_acquire(). If no users of the device
+ * function remain, set the mfpwm device to have no active device function,
+ * allowing other device functions to claim it.
+ */
+void mfpwm_release(const struct rockchip_mfpwm_func *pwmf);
+
+/**
+ * mfpwm_remove_func - remove a device function driver from the mfpwm
+ * @pwmf: pointer to the calling driver instance's &struct rockchip_mfpwm_func
+ *
+ * If the device function driver described by @pwmf is the currently active
+ * device function, then it'll have its mfpwm_acquires balanced and be removed
+ * as the active device function driver. Should only be called once all the
+ * clock enables have been balanced, as the function cannot balance this.
+ */
+void mfpwm_remove_func(struct rockchip_mfpwm_func *pwmf);
+
+#endif /* __SOC_ROCKCHIP_MFPWM_H__ */