[PATCH v5 2/6] mfd: Add Rockchip mfpwm driver

Nicolas Frattaroli
2026-04-20T13:53:58Z

With the Rockchip RK3576, the PWM IP used by Rockchip has changed
substantially. Looking at both the downstream pwm-rockchip driver as
well as the mainline pwm-rockchip driver made it clear that with all its
additional features and its differences from previous IP revisions, it
is best supported in a new driver.

This brings us to the question as to what such a new driver should be.
To me, it soon became clear that it should actually be several new
drivers, most prominently when Uwe Kleine-König let me know that I
should not implement the pwm subsystem's capture callback, but instead
write a counter driver for this functionality.

Combined with the other as-of-yet unimplemented functionality of this
new IP, it became apparent that it needs to be spread across several
subsystems.

For this reason, we add a new MFD core driver, called mfpwm (short for
"Multi-function PWM"). This "parent" driver makes sure that only one
device function driver is using the device at a time, and is in charge
of registering the MFD cell devices for the individual device functions
offered by the device.

An acquire/release pattern is used to guarantee that device function
drivers don't step on each other's toes.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
MAINTAINERS | 2 +
drivers/mfd/Kconfig | 16 ++
drivers/mfd/Makefile | 1 +
drivers/mfd/rockchip-mfpwm.c | 357 ++++++++++++++++++++++++++++
include/linux/mfd/rockchip-mfpwm.h | 470 +++++++++++++++++++++++++++++++++++++
5 files changed, 846 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 86f20cb563c6..d52731242a33 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -23178,6 +23178,8 @@ 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/mfd/rockchip-mfpwm.c
+F: include/linux/mfd/rockchip-mfpwm.h

ROCKCHIP RK3568 RANDOM NUMBER GENERATOR SUPPORT
M: Daniel Golle <daniel@makrotopia.org>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 7192c9d1d268..80b4e82c4937 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1378,6 +1378,22 @@ config MFD_RC5T583
Additional drivers must be enabled in order to use the
different functionality of the device.

+config MFD_ROCKCHIP_MFPWM
+ tristate "Rockchip multi-function PWM controller"
+ depends on ARCH_ROCKCHIP || COMPILE_TEST
+ depends on OF
+ depends on HAS_IOMEM
+ depends on COMMON_CLK
+ select MFD_CORE
+ 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. Drivers for them are implemented
+ in their respective subsystems.
+
config MFD_RK8XX
tristate
select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index e75e8045c28a..ebadbaea9e4a 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -231,6 +231,7 @@ obj-$(CONFIG_MFD_PALMAS) += palmas.o
obj-$(CONFIG_MFD_VIPERBOARD) += viperboard.o
obj-$(CONFIG_MFD_NTXEC) += ntxec.o
obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
+obj-$(CONFIG_MFD_ROCKCHIP_MFPWM) += rockchip-mfpwm.o
obj-$(CONFIG_MFD_RK8XX) += rk8xx-core.o
obj-$(CONFIG_MFD_RK8XX_I2C) += rk8xx-i2c.o
obj-$(CONFIG_MFD_RK8XX_SPI) += rk8xx-spi.o
diff --git a/drivers/mfd/rockchip-mfpwm.c b/drivers/mfd/rockchip-mfpwm.c
new file mode 100644
index 000000000000..72d04982b961
--- /dev/null
+++ b/drivers/mfd/rockchip-mfpwm.c
@@ -0,0 +1,357 @@
+// 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/mfd/core.h>
+#include <linux/mfd/rockchip-mfpwm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.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
+ * @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 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 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");
+
+int mfpwm_get_mode(const struct rockchip_mfpwm_func *pwmf)
+{
+ struct rockchip_mfpwm *mfpwm;
+ int ret;
+
+ ret = mfpwm_check_pwmf(pwmf, "mfpwm_acquire");
+ if (ret)
+ return ret;
+
+ mfpwm = pwmf->parent;
+
+ guard(spinlock_irqsave)(&mfpwm->state_lock);
+
+ if (!rockchip_pwm_v4_is_enabled(mfpwm_reg_read(mfpwm->base, PWMV4_REG_ENABLE)))
+ return -1;
+
+ return mfpwm_reg_read(mfpwm->base, PWMV4_REG_CTRL) & PWMV4_MODE_MASK;
+}
+EXPORT_SYMBOL_NS_GPL(mfpwm_get_mode, "ROCKCHIP_MFPWM");
+
+/**
+ * mfpwm_register_subdev - register a single mfpwm_func
+ * @mfpwm: pointer to the parent &struct rockchip_mfpwm
+ * @name: sub-device name string
+ *
+ * Allocate a single &struct mfpwm_func, fill its members with appropriate data,
+ * and register a new mfd cell.
+ *
+ * Returns: 0 on success, negative errno on error
+ */
+static int mfpwm_register_subdev(struct rockchip_mfpwm *mfpwm,
+ const char *name)
+{
+ struct rockchip_mfpwm_func *func;
+ struct mfd_cell cell = {};
+
+ 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;
+ cell.name = name;
+ cell.platform_data = func;
+ cell.pdata_size = sizeof(*func);
+
+ return devm_mfd_add_devices(&mfpwm->pdev->dev, func->id, &cell, 1, NULL,
+ 0, NULL);
+}
+
+static int mfpwm_register_subdevs(struct rockchip_mfpwm *mfpwm)
+{
+ int ret;
+
+ ret = mfpwm_register_subdev(mfpwm, "rockchip-pwm-v4");
+ if (ret)
+ return ret;
+
+ ret = mfpwm_register_subdev(mfpwm, "rockchip-pwm-capture");
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+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_unprepare(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/linux/mfd/rockchip-mfpwm.h b/include/linux/mfd/rockchip-mfpwm.h
new file mode 100644
index 000000000000..dbf1588a4382
--- /dev/null
+++ b/include/linux/mfd/rockchip-mfpwm.h
@@ -0,0 +1,470 @@
+/* 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/bits.h>
+#include <linux/clk.h>
+#include <linux/hw_bitfield.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
+ * [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
+ */
+
+#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_WM16(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_WM16(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_WM16(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_WM16_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_WM16(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_WM16(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_WM16(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_WM16(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_WM16(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_WM16(GENMASK(8, 6), (v))
+/* [05:05] RW | Aligned Mode, 0 = Valid, 1 = Invalid */
+#define PWMV4_CTRL_UNALIGNED(v) FIELD_PREP_WM16(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_WM16(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_WM16(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_WM16(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_WM16(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_WM16(PWMV4_INT_LPC, \
+ ((v) ? 1 : 0))
+#define PWMV4_INT_HPC_W(v) FIELD_PREP_WM16(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
+ */
+extern 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.
+ */
+extern void mfpwm_release(const struct rockchip_mfpwm_func *pwmf);
+
+/**
+ * mfpwm_get_mode - get the current mode the hardware is in
+ * @pwmf: pointer to a &struct rockchip_mfpwm_func
+ *
+ * Check the hardware registers of the PWM hardware to determine which mode it
+ * is currently operating in, if any.
+ *
+ * Returns:
+ * - %-EINVAL if @pwmf is %NULL or an error pointer
+ * - %-1 if the PWM hardware is off, regardless of operating mode
+ * - %PWMV4_MODE_ONESHOT if PWM hardware is in one-shot output mode
+ * - %PWMV4_MODE_CONT if PWM hardware is in continuous output mode
+ * - %PWMV4_MODE_CAPTURE if PWM hardware is in capture mode
+ */
+extern int mfpwm_get_mode(const struct rockchip_mfpwm_func *pwmf);
+
+#endif /* __SOC_ROCKCHIP_MFPWM_H__ */

--
2.53.0