diff mbox series

[v2,09/11] reset: eyeq: add platform driver

Message ID 20240503-mbly-olb-v2-9-95ce5a1e18fe@bootlin.com (mailing list archive)
State Superseded
Headers show
Series Add Mobileye EyeQ system controller support (clk, reset, pinctrl) | expand

Commit Message

Théo Lebrun May 3, 2024, 2:20 p.m. UTC
Add Mobileye EyeQ reset controller driver, for EyeQ5, EyeQ6L and EyeQ6H
SoCs. Instances belong to a shared register region called OLB.

There is one OLB instance for EyeQ5 and EyeQ6L. There are seven OLB
instances on EyeQ6H; three have a reset controller embedded:
 - West and east get handled by the same compatible.
 - Acc (accelerator) is another one.

Each instance vary in the number and types of reset domains.
Instances with single domain expect a single cell, others two.

Device is only used as MFD cell. Inherit parent OF node for property
fetching helpers to work. Also, don't register match table on platform
driver: rather fetch match-data manually using of_match_node(). Match
table therefore targets parent MFD compatible.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
 MAINTAINERS                |   1 +
 drivers/reset/Kconfig      |  13 ++
 drivers/reset/Makefile     |   1 +
 drivers/reset/reset-eyeq.c | 541 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 556 insertions(+)
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index f386e9da2cd0..36f4001c7f51 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14931,6 +14931,7 @@  F:	arch/mips/boot/dts/mobileye/
 F:	arch/mips/configs/eyeq5_defconfig
 F:	arch/mips/mobileye/board-epm5.its.S
 F:	drivers/clk/clk-eyeq5.c
+F:	drivers/reset/reset-eyeq5.c
 F:	include/dt-bindings/clock/mobileye,eyeq5-clk.h
 
 MODULE SUPPORT
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 85b27c42cf65..18ee99ed8ecc 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -66,6 +66,19 @@  config RESET_BRCMSTB_RESCAL
 	  This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1 on
 	  BCM7216.
 
+config RESET_EYEQ
+	bool "Mobileye EyeQ reset controller"
+	depends on MFD_SYSCON
+	depends on MACH_EYEQ5 || MACH_EYEQ6H || COMPILE_TEST
+	default MACH_EYEQ5 || MACH_EYEQ6H
+	help
+	  This enables the Mobileye EyeQ reset controller, used in EyeQ5, EyeQ6L
+	  and EyeQ6H SoCs.
+
+	  It has one or more domains, with a varying number of resets in each.
+	  Registers are located in a shared register region called OLB. EyeQ6H
+	  has multiple reset instances.
+
 config RESET_GPIO
 	tristate "GPIO reset controller"
 	help
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index fd8b49fa46fc..a4e6fea29800 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -11,6 +11,7 @@  obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
 obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
 obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
 obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
+obj-$(CONFIG_RESET_EYEQ) += reset-eyeq.o
 obj-$(CONFIG_RESET_GPIO) += reset-gpio.o
 obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
 obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
diff --git a/drivers/reset/reset-eyeq.c b/drivers/reset/reset-eyeq.c
new file mode 100644
index 000000000000..07e08b6231af
--- /dev/null
+++ b/drivers/reset/reset-eyeq.c
@@ -0,0 +1,541 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Reset driver for the Mobileye EyeQ5, EyeQ6L and EyeQ6H platforms.
+ *
+ * Controllers live in a shared register region called OLB. EyeQ5 and EyeQ6L
+ * have a single OLB instance for a single reset controller. EyeQ6H has seven
+ * OLB instances; three host reset controllers.
+ *
+ * Each reset controller has one or more domain. Domains are of a given type
+ * (see enum eqr_domain_type), with a valid offset mask (up to 32 resets per
+ * domain).
+ *
+ * Domain types define expected behavior: one-register-per-reset,
+ * one-bit-per-reset, status detection method, busywait duration, etc.
+ *
+ * We use eqr_ as prefix, as-in "EyeQ Reset", but way shorter.
+ *
+ * Known resets in EyeQ5 domain 0 (type EQR_EYEQ5_SARCR):
+ *  3. CAN0	 4. CAN1	 5. CAN2	 6. SPI0
+ *  7. SPI1	 8. SPI2	 9. SPI3	10. UART0
+ * 11. UART1	12. UART2	13. I2C0	14. I2C1
+ * 15. I2C2	16. I2C3	17. I2C4	18. TIMER0
+ * 19. TIMER1	20. TIMER2	21. TIMER3	22. TIMER4
+ * 23. WD0	24. EXT0	25. EXT1	26. GPIO
+ * 27. WD1
+ *
+ * Known resets in EyeQ5 domain 1 (type EQR_EYEQ5_ACRP):
+ *  0. VMP0	 1. VMP1	 2. VMP2	 3. VMP3
+ *  4. PMA0	 5. PMA1	 6. PMAC0	 7. PMAC1
+ *  8. MPC0	 9. MPC1	10. MPC2	11. MPC3
+ * 12. MPC4
+ *
+ * Known resets in EyeQ5 domain 2 (type EQR_EYEQ5_PCIE):
+ *  0. PCIE0_CORE	 1. PCIE0_APB		 2. PCIE0_LINK_AXI	 3. PCIE0_LINK_MGMT
+ *  4. PCIE0_LINK_HOT	 5. PCIE0_LINK_PIPE	 6. PCIE1_CORE		 7. PCIE1_APB
+ *  8. PCIE1_LINK_AXI	 9. PCIE1_LINK_MGMT	10. PCIE1_LINK_HOT	11. PCIE1_LINK_PIPE
+ * 12. MULTIPHY		13. MULTIPHY_APB	15. PCIE0_LINK_MGMT	16. PCIE1_LINK_MGMT
+ * 17. PCIE0_LINK_PM	18. PCIE1_LINK_PM
+ *
+ * Known resets in EyeQ6L domain 0 (type EQR_EYEQ5_SARCR):
+ *  0. SPI0	 1. SPI1	 2. UART0	 3. I2C0
+ *  4. I2C1	 5. TIMER0	 6. TIMER1	 7. TIMER2
+ *  8. TIMER3	 9. WD0		10. WD1		11. EXT0
+ * 12. EXT1	13. GPIO
+ *
+ * Known resets in EyeQ6L domain 1 (type EQR_EYEQ5_ACRP):
+ *  0. VMP0	 1. VMP1	 2. VMP2	 3. VMP3
+ *  4. PMA0	 5. PMA1	 6. PMAC0	 7. PMAC1
+ *  8. MPC0	 9. MPC1	10. MPC2	11. MPC3
+ * 12. MPC4
+ *
+ * Known resets in EyeQ6H west/east (type EQR_EYEQ6H_SARCR):
+ *  0. CAN	 1. SPI0	 2. SPI1	 3. UART0
+ *  4. UART1	 5. I2C0	 6. I2C1	 7. -hole-
+ *  8. TIMER0	 9. TIMER1	10. WD		11. EXT TIMER
+ * 12. GPIO
+ *
+ * Known resets in EyeQ6H acc (type EQR_EYEQ5_ACRP):
+ *  1. XNN0	 2. XNN1	 3. XNN2	 4. XNN3
+ *  5. VMP0	 6. VMP1	 7. VMP2	 8. VMP3
+ *  9. PMA0	10. PMA1	11. MPC0	12. MPC1
+ * 13. MPC2	14. MPC3	15. PERIPH
+ *
+ * Abbreviations:
+ *  - PMA: Programmable Macro Array
+ *  - MPC: Multi-threaded Processing Clusters
+ *  - VMP: Vector Microcode Processors
+ *
+ * Copyright (C) 2024 Mobileye Vision Technologies Ltd.
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/bug.h>
+#include <linux/cleanup.h>
+#include <linux/container_of.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/lockdep.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+/*
+ * A reset ID, as returned by eqr_of_xlate, is a (domain, offset) pair.
+ * Low byte is domain, rest is offset.
+ */
+#define ID_DOMAIN_MASK	GENMASK(7, 0)
+#define ID_OFFSET_MASK	GENMASK(31, 8)
+
+enum eqr_domain_type {
+	EQR_EYEQ5_SARCR,
+	EQR_EYEQ5_ACRP,
+	EQR_EYEQ5_PCIE,
+	EQR_EYEQ6H_SARCR,
+};
+
+/*
+ * Domain type EQR_EYEQ5_SARCR register offsets.
+ */
+#define EQR_EYEQ5_SARCR_REQUEST		(0x000)
+#define EQR_EYEQ5_SARCR_STATUS		(0x004)
+
+/*
+ * Domain type EQR_EYEQ5_ACRP register masks.
+ * Registers are: base + 4 * offset.
+ */
+#define EQR_EYEQ5_ACRP_PD_REQ		BIT(0)
+#define EQR_EYEQ5_ACRP_ST_POWER_DOWN	BIT(27)
+#define EQR_EYEQ5_ACRP_ST_ACTIVE	BIT(29)
+
+/*
+ * Domain type EQR_EYEQ6H_SARCR register offsets.
+ */
+#define EQR_EYEQ6H_SARCR_RST_REQUEST	(0x000)
+#define EQR_EYEQ6H_SARCR_CLK_STATUS	(0x004)
+#define EQR_EYEQ6H_SARCR_RST_STATUS	(0x008)
+#define EQR_EYEQ6H_SARCR_CLK_REQUEST	(0x00C)
+
+struct eqr_busy_wait_timings {
+	unsigned long sleep_us;
+	unsigned long timeout_us;
+};
+
+static const struct eqr_busy_wait_timings eqr_timings[] = {
+	[EQR_EYEQ5_SARCR]	= {1, 10},
+	[EQR_EYEQ5_ACRP]	= {1, 40 * USEC_PER_MSEC}, /* LBIST implies long timeout. */
+	/* EQR_EYEQ5_PCIE does no busy waiting. */
+	[EQR_EYEQ6H_SARCR]	= {1, 400},
+};
+
+#define EQR_MAX_DOMAIN_COUNT 3
+
+struct eqr_domain_descriptor {
+	enum eqr_domain_type	type;
+	u32			valid_mask;
+};
+
+struct eqr_match_data {
+	unsigned int				domain_count;
+	const struct eqr_domain_descriptor	*domains;
+};
+
+struct eqr_private {
+	struct mutex			mutexes[EQR_MAX_DOMAIN_COUNT];
+	void __iomem			*bases[EQR_MAX_DOMAIN_COUNT];
+	const struct eqr_match_data	*data;
+	struct reset_controller_dev	rcdev;
+};
+
+#define rcdev_to_priv(rcdev) container_of(rcdev, struct eqr_private, rcdev)
+
+static u32 eqr_double_readl(void __iomem *addr_a, void __iomem *addr_b,
+			    u32 *dest_a, u32 *dest_b)
+{
+	*dest_a = readl(addr_a);
+	*dest_b = readl(addr_b);
+	return 0; /* read_poll_timeout() op argument must return something. */
+}
+
+static int eqr_busy_wait_locked(struct eqr_private *priv, struct device *dev,
+				u32 domain, u32 offset, bool assert)
+{
+	enum eqr_domain_type domain_type = priv->data->domains[domain].type;
+	unsigned long sleep_us, timeout_us;
+	u32 val, mask, val0, val1;
+	void __iomem *base, *reg;
+	int ret;
+
+	lockdep_assert_held(&priv->mutexes[domain]);
+
+	base = priv->bases[domain];
+	sleep_us = eqr_timings[domain_type].sleep_us;
+	timeout_us = eqr_timings[domain_type].timeout_us;
+
+	switch (domain_type) {
+	case EQR_EYEQ5_SARCR:
+		reg = base + EQR_EYEQ5_SARCR_STATUS;
+		mask = BIT(offset);
+
+		ret = readl_poll_timeout(reg, val, !(val & mask) == assert,
+					 sleep_us, timeout_us);
+		break;
+
+	case EQR_EYEQ5_ACRP:
+		reg = base + 4 * offset;
+		if (assert)
+			mask = EQR_EYEQ5_ACRP_ST_POWER_DOWN;
+		else
+			mask = EQR_EYEQ5_ACRP_ST_ACTIVE;
+
+		ret = readl_poll_timeout(reg, val, !!(val & mask),
+					 sleep_us, timeout_us);
+		break;
+
+	case EQR_EYEQ5_PCIE:
+		ret = 0; /* No busy waiting. */
+		break;
+
+	case EQR_EYEQ6H_SARCR:
+		/*
+		 * Wait until both bits change:
+		 *	readl(base + EQR_EYEQ6H_SARCR_RST_STATUS) & BIT(offset)
+		 *	readl(base + EQR_EYEQ6H_SARCR_CLK_STATUS) & BIT(offset)
+		 */
+		mask = BIT(offset);
+		ret = read_poll_timeout(eqr_double_readl, val,
+					(!(val0 & mask) == assert) &&
+						(!(val1 & mask) == assert),
+					sleep_us, timeout_us, false,
+					base + EQR_EYEQ6H_SARCR_RST_STATUS,
+					base + EQR_EYEQ6H_SARCR_CLK_STATUS,
+					&val0, &val1);
+		break;
+
+	default:
+		WARN_ON(1);
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret == -ETIMEDOUT)
+		dev_dbg(dev, "%u-%u: timeout\n", domain, offset);
+	return ret;
+}
+
+static void eqr_assert_locked(struct eqr_private *priv, u32 domain, u32 offset)
+{
+	enum eqr_domain_type domain_type = priv->data->domains[domain].type;
+	void __iomem *base, *reg;
+	u32 val;
+
+	lockdep_assert_held(&priv->mutexes[domain]);
+
+	base = priv->bases[domain];
+
+	switch (domain_type) {
+	case EQR_EYEQ5_SARCR:
+		reg = base + EQR_EYEQ5_SARCR_REQUEST;
+		writel(readl(reg) & ~BIT(offset), reg);
+		break;
+
+	case EQR_EYEQ5_ACRP:
+		reg = base + 4 * offset;
+		writel(readl(reg) | EQR_EYEQ5_ACRP_PD_REQ, reg);
+		break;
+
+	case EQR_EYEQ5_PCIE:
+		writel(readl(base) & ~BIT(offset), base);
+		break;
+
+	case EQR_EYEQ6H_SARCR:
+		val = readl(base + EQR_EYEQ6H_SARCR_RST_REQUEST);
+		val &= ~BIT(offset);
+		writel(val, base + EQR_EYEQ6H_SARCR_RST_REQUEST);
+		writel(val, base + EQR_EYEQ6H_SARCR_CLK_REQUEST);
+		break;
+
+	default:
+		WARN_ON(1);
+		break;
+	}
+}
+
+static int eqr_assert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct eqr_private *priv = rcdev_to_priv(rcdev);
+	u32 domain = FIELD_GET(ID_DOMAIN_MASK, id);
+	u32 offset = FIELD_GET(ID_OFFSET_MASK, id);
+
+	dev_dbg(rcdev->dev, "%u-%u: assert request\n", domain, offset);
+
+	guard(mutex)(&priv->mutexes[domain]);
+	eqr_assert_locked(priv, domain, offset);
+	return eqr_busy_wait_locked(priv, rcdev->dev, domain, offset, true);
+}
+
+static void eqr_deassert_locked(struct eqr_private *priv, u32 domain,
+				u32 offset)
+{
+	enum eqr_domain_type domain_type = priv->data->domains[domain].type;
+	void __iomem *base, *reg;
+	u32 val;
+
+	lockdep_assert_held(&priv->mutexes[domain]);
+
+	base = priv->bases[domain];
+
+	switch (domain_type) {
+	case EQR_EYEQ5_SARCR:
+		reg = base + EQR_EYEQ5_SARCR_REQUEST;
+		writel(readl(reg) | BIT(offset), reg);
+		break;
+
+	case EQR_EYEQ5_ACRP:
+		reg = base + 4 * offset;
+		writel(readl(reg) & ~EQR_EYEQ5_ACRP_PD_REQ, reg);
+		break;
+
+	case EQR_EYEQ5_PCIE:
+		writel(readl(base) | BIT(offset), base);
+		break;
+
+	case EQR_EYEQ6H_SARCR:
+		val = readl(base + EQR_EYEQ6H_SARCR_RST_REQUEST);
+		val |= BIT(offset);
+		writel(val, base + EQR_EYEQ6H_SARCR_RST_REQUEST);
+		writel(val, base + EQR_EYEQ6H_SARCR_CLK_REQUEST);
+		break;
+
+	default:
+		WARN_ON(1);
+		break;
+	}
+}
+
+static int eqr_deassert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct eqr_private *priv = rcdev_to_priv(rcdev);
+	u32 domain = FIELD_GET(ID_DOMAIN_MASK, id);
+	u32 offset = FIELD_GET(ID_OFFSET_MASK, id);
+
+	dev_dbg(rcdev->dev, "%u-%u: deassert request\n", domain, offset);
+
+	guard(mutex)(&priv->mutexes[domain]);
+	eqr_deassert_locked(priv, domain, offset);
+	return eqr_busy_wait_locked(priv, rcdev->dev, domain, offset, false);
+}
+
+static int eqr_status(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	u32 domain = FIELD_GET(ID_DOMAIN_MASK, id);
+	struct eqr_private *priv = rcdev_to_priv(rcdev);
+	enum eqr_domain_type domain_type = priv->data->domains[domain].type;
+	u32 offset = FIELD_GET(ID_OFFSET_MASK, id);
+	void __iomem *base, *reg;
+
+	dev_dbg(rcdev->dev, "%u-%u: status request\n", domain, offset);
+
+	guard(mutex)(&priv->mutexes[domain]);
+
+	base = priv->bases[domain];
+
+	switch (domain_type) {
+	case EQR_EYEQ5_SARCR:
+		reg = base + EQR_EYEQ5_SARCR_STATUS;
+		return !(readl(reg) & BIT(offset));
+	case EQR_EYEQ5_ACRP:
+		reg = base + 4 * offset;
+		return !(readl(reg) & EQR_EYEQ5_ACRP_ST_ACTIVE);
+	case EQR_EYEQ5_PCIE:
+		return !(readl(base) & BIT(offset));
+	case EQR_EYEQ6H_SARCR:
+		reg = base + EQR_EYEQ6H_SARCR_RST_STATUS;
+		return !(readl(reg) & BIT(offset));
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct reset_control_ops eqr_ops = {
+	.assert	  = eqr_assert,
+	.deassert = eqr_deassert,
+	.status	  = eqr_status,
+};
+
+static int eqr_of_xlate_internal(struct reset_controller_dev *rcdev,
+				 u32 domain, u32 offset)
+{
+	struct eqr_private *priv = rcdev_to_priv(rcdev);
+
+	if (domain >= priv->data->domain_count || offset > 31 ||
+	    !(priv->data->domains[domain].valid_mask & BIT(offset))) {
+		dev_err(rcdev->dev, "%u-%u: invalid reset\n", domain, offset);
+		return -EINVAL;
+	}
+
+	return FIELD_PREP(ID_DOMAIN_MASK, domain) | FIELD_PREP(ID_OFFSET_MASK, offset);
+}
+
+static int eqr_of_xlate_onecell(struct reset_controller_dev *rcdev,
+				const struct of_phandle_args *reset_spec)
+{
+	return eqr_of_xlate_internal(rcdev, 0, reset_spec->args[0]);
+}
+
+static int eqr_of_xlate_twocells(struct reset_controller_dev *rcdev,
+				 const struct of_phandle_args *reset_spec)
+{
+	return eqr_of_xlate_internal(rcdev, reset_spec->args[0], reset_spec->args[1]);
+}
+
+static const struct eqr_domain_descriptor eqr_eyeq5_domains[] = {
+	{
+		.type = EQR_EYEQ5_SARCR,
+		.valid_mask = 0xFFFFFF8,
+	},
+	{
+		.type = EQR_EYEQ5_ACRP,
+		.valid_mask = 0x0001FFF,
+	},
+	{
+		.type = EQR_EYEQ5_PCIE,
+		.valid_mask = 0x007BFFF,
+	},
+};
+
+static const struct eqr_match_data eqr_eyeq5_data = {
+	.domain_count	= ARRAY_SIZE(eqr_eyeq5_domains),
+	.domains	= eqr_eyeq5_domains,
+};
+
+static const struct eqr_domain_descriptor eqr_eyeq6l_domains[] = {
+	{
+		.type = EQR_EYEQ5_SARCR,
+		.valid_mask = 0x3FFF,
+	},
+	{
+		.type = EQR_EYEQ5_ACRP,
+		.valid_mask = 0x00FF,
+	},
+};
+
+static const struct eqr_match_data eqr_eyeq6l_data = {
+	.domain_count	= ARRAY_SIZE(eqr_eyeq6l_domains),
+	.domains	= eqr_eyeq6l_domains,
+};
+
+/* West and east OLBs each have an instance. */
+static const struct eqr_domain_descriptor eqr_eyeq6h_we_domains[] = {
+	{
+		.type = EQR_EYEQ6H_SARCR,
+		.valid_mask = 0x1F7F,
+	},
+};
+
+static const struct eqr_match_data eqr_eyeq6h_we_data = {
+	.domain_count	= ARRAY_SIZE(eqr_eyeq6h_we_domains),
+	.domains	= eqr_eyeq6h_we_domains,
+};
+
+static const struct eqr_domain_descriptor eqr_eyeq6h_acc_domains[] = {
+	{
+		.type = EQR_EYEQ5_ACRP,
+		.valid_mask = 0x7FFF,
+	},
+};
+
+static const struct eqr_match_data eqr_eyeq6h_acc_data = {
+	.domain_count	= ARRAY_SIZE(eqr_eyeq6h_acc_domains),
+	.domains	= eqr_eyeq6h_acc_domains,
+};
+
+/*
+ * Table describes OLB system-controller compatibles and is NOT registered on
+ * platform driver. It gets matched against MFD parent OF node.
+ */
+static const struct of_device_id eqr_match_table[] = {
+	{ .compatible = "mobileye,eyeq5-olb", .data = &eqr_eyeq5_data },
+	{ .compatible = "mobileye,eyeq6l-olb", .data = &eqr_eyeq6l_data },
+	{ .compatible = "mobileye,eyeq6h-west-olb", .data = &eqr_eyeq6h_we_data },
+	{ .compatible = "mobileye,eyeq6h-east-olb", .data = &eqr_eyeq6h_we_data },
+	{ .compatible = "mobileye,eyeq6h-acc-olb", .data = &eqr_eyeq6h_acc_data },
+	{}
+};
+MODULE_DEVICE_TABLE(of, eqr_match_table);
+
+static int eqr_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	struct eqr_private *priv;
+	unsigned int i;
+	int ret;
+
+	/* Spawned as MFD sub-device, use parent's OF node. */
+	if (!dev->of_node) {
+		device_set_of_node_from_dev(dev, dev->parent);
+		if (!dev->of_node)
+			return -ENODEV;
+	}
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	match = of_match_node(eqr_match_table, dev->of_node);
+	if (!match || !match->data)
+		return -ENODEV;
+
+	priv->data = match->data;
+
+	priv->rcdev.ops = &eqr_ops;
+	priv->rcdev.owner = THIS_MODULE;
+	priv->rcdev.dev = dev;
+	priv->rcdev.of_node = dev->of_node;
+
+	if (priv->data->domain_count == 1) {
+		priv->rcdev.of_reset_n_cells = 1;
+		priv->rcdev.of_xlate = eqr_of_xlate_onecell;
+	} else {
+		priv->rcdev.of_reset_n_cells = 2;
+		priv->rcdev.of_xlate = eqr_of_xlate_twocells;
+	}
+
+	for (i = 0; i < priv->data->domain_count; i++) {
+		priv->bases[i] = devm_platform_ioremap_resource(pdev, i);
+		if (IS_ERR(priv->bases[i]))
+			return PTR_ERR(priv->bases[i]);
+	}
+
+	for (i = 0; i < priv->data->domain_count; i++)
+		mutex_init(&priv->mutexes[i]);
+
+	priv->rcdev.nr_resets = 0;
+	for (i = 0; i < priv->data->domain_count; i++)
+		priv->rcdev.nr_resets += hweight32(priv->data->domains[i].valid_mask);
+
+	ret = devm_reset_controller_register(dev, &priv->rcdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed registering reset controller\n");
+
+	return 0;
+}
+
+static struct platform_driver eqr_driver = {
+	.probe = eqr_probe,
+	.driver = {
+		.name = "reset-eyeq",
+	},
+};
+builtin_platform_driver(eqr_driver);