Merge tag 'reset-for-4.8-3' of git://git.pengutronix.de/git/pza/linux into next/drivers

Merge "Reset controller changes for v4.8, part 3" from Philipp Zabel:

- change request API to be more explicit about the difference between
  exclusive and shared resets (the former guarantee the reset line is
  asserted immediately when reset_control_assert is called, the latter
  are refcounted and do not guarantee this).
- add Hisilicon hi6220 media subsystem reset controller support
- add TI SYSCON based reset controller support

* tag 'reset-for-4.8-3' of git://git.pengutronix.de/git/pza/linux:
  reset: add TI SYSCON based reset driver
  Documentation: dt: reset: Add TI syscon reset binding
  reset: hisilicon: Add hi6220 media subsystem reset support
  reset: hisilicon: Change to syscon register access
  arm64: dts: hi6220: Add media subsystem reset dts
  reset: hisilicon: Add media reset controller binding
  reset: TRIVIAL: Add line break at same place for similar APIs
  reset: Supply *_shared variant calls when using *_optional APIs
  reset: Supply *_shared variant calls when using of_* API
  reset: Ensure drivers are explicit when requesting reset lines
  reset: Reorder inline reset_control_get*() wrappers

Documentation/devicetree/bindings/reset/hisilicon,hi6220-reset.txt

@@ -8,7 +8,9 @@ The reset controller registers are part of the system-ctl block on
 hi6220 SoC.
 
 Required properties:
-- compatible: may be "hisilicon,hi6220-sysctrl"
+- compatible: should be one of the following:
+  - "hisilicon,hi6220-sysctrl", "syscon" : For peripheral reset controller.
+  - "hisilicon,hi6220-mediactrl", "syscon" : For media reset controller.
 - reg: should be register base and length as documented in the
   datasheet
 - #reset-cells: 1, see below

Documentation/devicetree/bindings/reset/ti-syscon-reset.txt

+TI SysCon Reset Controller
+=======================
+
+Almost all SoCs have hardware modules that require reset control in addition
+to clock and power control for their functionality. The reset control is
+typically provided by means of memory-mapped I/O registers. These registers are
+sometimes a part of a larger register space region implementing various
+functionalities. This register range is best represented as a syscon node to
+allow multiple entities to access their relevant registers in the common
+register space.
+
+A SysCon Reset Controller node defines a device that uses a syscon node
+and provides reset management functionality for various hardware modules
+present on the SoC.
+
+SysCon Reset Controller Node
+============================
+Each of the reset provider/controller nodes should be a child of a syscon
+node and have the following properties.
+
+Required properties:
+--------------------
+ - compatible		: Should be,
+			    "ti,k2e-pscrst"
+			    "ti,k2l-pscrst"
+			    "ti,k2hk-pscrst"
+			    "ti,syscon-reset"
+ - #reset-cells		: Should be 1. Please see the reset consumer node below
+			  for usage details
+ - ti,reset-bits	: Contains the reset control register information
+			  Should contain 7 cells for each reset exposed to
+			  consumers, defined as:
+			    Cell #1 : offset of the reset assert control
+			              register from the syscon register base
+			    Cell #2 : bit position of the reset in the reset
+			              assert control register
+			    Cell #3 : offset of the reset deassert control
+			              register from the syscon register base
+			    Cell #4 : bit position of the reset in the reset
+			              deassert control register
+			    Cell #5 : offset of the reset status register
+			              from the syscon register base
+			    Cell #6 : bit position of the reset in the
+			              reset status register
+			    Cell #7 : Flags used to control reset behavior,
+			              availible flags defined in the DT include
+			              file <dt-bindings/reset/ti-syscon.h>
+
+SysCon Reset Consumer Nodes
+===========================
+Each of the reset consumer nodes should have the following properties,
+in addition to their own properties.
+
+Required properties:
+--------------------
+ - resets	: A phandle to the reset controller node and an index number
+		  to a reset specifier as defined above.
+
+Please also refer to Documentation/devicetree/bindings/reset/reset.txt for
+common reset controller usage by consumers.
+
+Example:
+--------
+The following example demonstrates a syscon node, the reset controller node
+using the syscon node, and a consumer (a DSP device) on the TI Keystone 2
+Edison SoC.
+
+/ {
+	soc {
+		psc: power-sleep-controller@02350000 {
+			compatible = "syscon", "simple-mfd";
+			reg = <0x02350000 0x1000>;
+
+			pscrst: psc-reset {
+				compatible = "ti,k2e-pscrst", "ti,syscon-reset";
+				#reset-cells = <1>;
+
+				ti,reset-bits = <
+					0xa3c 8 0xa3c 8 0x83c 8 (ASSERT_SET|DEASSERT_CLEAR|STATUS_SET)   /* 0: pcrst-dsp0 */
+					0xa40 5 0xa44 3 0     0 (ASSERT_SET|DEASSERT_CLEAR|STATUS_NONE)  /* 1: pcrst-example */
+				>;
+			};
+		};
+
+		dsp0: dsp0 {
+			...
+			resets = <&pscrst 0>;
+			...
+		};
+	};
+};

arch/arm64/boot/dts/hisilicon/hi6220.dtsi

@@ -5,6 +5,7 @@
  */
 
 #include <dt-bindings/interrupt-controller/arm-gic.h>
+#include <dt-bindings/reset/hisi,hi6220-resets.h>
 #include <dt-bindings/clock/hi6220-clock.h>
 #include <dt-bindings/pinctrl/hisi.h>
 #include <dt-bindings/thermal/thermal.h>
@@ -252,6 +253,7 @@ media_ctrl: media_ctrl@f4410000 {
 			compatible = "hisilicon,hi6220-mediactrl", "syscon";
 			reg = <0x0 0xf4410000 0x0 0x1000>;
 			#clock-cells = <1>;
+			#reset-cells = <1>;
 		};
 
 		pm_ctrl: pm_ctrl@f7032000 {

drivers/reset/Kconfig

@@ -17,6 +17,16 @@ if RESET_CONTROLLER
 config RESET_OXNAS
 	bool
 
+config TI_SYSCON_RESET
+	tristate "TI SYSCON Reset Driver"
+	depends on HAS_IOMEM
+	select MFD_SYSCON
+	help
+	  This enables the reset driver support for TI devices with
+	  memory-mapped reset registers as part of a syscon device node. If
+	  you wish to use the reset framework for such memory-mapped devices,
+	  say Y here. Otherwise, say N.
+
 source "drivers/reset/sti/Kconfig"
 source "drivers/reset/hisilicon/Kconfig"
 

drivers/reset/Makefile

@@ -10,3 +10,4 @@ obj-$(CONFIG_ARCH_HISI) += hisilicon/
 obj-$(CONFIG_ARCH_ZYNQ) += reset-zynq.o
 obj-$(CONFIG_ATH79) += reset-ath79.o
 obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o
+obj-$(CONFIG_TI_SYSCON_RESET) += reset-ti-syscon.o

drivers/reset/hisilicon/hi6220_reset.c

 /*
  * Hisilicon Hi6220 reset controller driver
  *
- * Copyright (c) 2015 Hisilicon Limited.
+ * Copyright (c) 2016 Linaro Limited.
+ * Copyright (c) 2015-2016 Hisilicon Limited.
  *
  * Author: Feng Chen <puck.chen@hisilicon.com>
  *
@@ -15,81 +16,130 @@
 #include <linux/module.h>
 #include <linux/bitops.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
 #include <linux/reset-controller.h>
 #include <linux/reset.h>
 #include <linux/platform_device.h>
 
-#define ASSERT_OFFSET            0x300
-#define DEASSERT_OFFSET          0x304
-#define MAX_INDEX                0x509
+#define PERIPH_ASSERT_OFFSET      0x300
+#define PERIPH_DEASSERT_OFFSET    0x304
+#define PERIPH_MAX_INDEX          0x509
+
+#define SC_MEDIA_RSTEN            0x052C
+#define SC_MEDIA_RSTDIS           0x0530
+#define MEDIA_MAX_INDEX           8
 
 #define to_reset_data(x) container_of(x, struct hi6220_reset_data, rc_dev)
 
+enum hi6220_reset_ctrl_type {
+	PERIPHERAL,
+	MEDIA,
+};
+
 struct hi6220_reset_data {
-	void __iomem			*assert_base;
-	void __iomem			*deassert_base;
-	struct reset_controller_dev	rc_dev;
+	struct reset_controller_dev rc_dev;
+	struct regmap *regmap;
 };
 
-static int hi6220_reset_assert(struct reset_controller_dev *rc_dev,
-			       unsigned long idx)
+static int hi6220_peripheral_assert(struct reset_controller_dev *rc_dev,
+				    unsigned long idx)
 {
 	struct hi6220_reset_data *data = to_reset_data(rc_dev);
+	struct regmap *regmap = data->regmap;
+	u32 bank = idx >> 8;
+	u32 offset = idx & 0xff;
+	u32 reg = PERIPH_ASSERT_OFFSET + bank * 0x10;
 
-	int bank = idx >> 8;
-	int offset = idx & 0xff;
+	return regmap_write(regmap, reg, BIT(offset));
+}
 
-	writel(BIT(offset), data->assert_base + (bank * 0x10));
+static int hi6220_peripheral_deassert(struct reset_controller_dev *rc_dev,
+				      unsigned long idx)
+{
+	struct hi6220_reset_data *data = to_reset_data(rc_dev);
+	struct regmap *regmap = data->regmap;
+	u32 bank = idx >> 8;
+	u32 offset = idx & 0xff;
+	u32 reg = PERIPH_DEASSERT_OFFSET + bank * 0x10;
 
-	return 0;
+	return regmap_write(regmap, reg, BIT(offset));
 }
 
-static int hi6220_reset_deassert(struct reset_controller_dev *rc_dev,
-				 unsigned long idx)
+static const struct reset_control_ops hi6220_peripheral_reset_ops = {
+	.assert = hi6220_peripheral_assert,
+	.deassert = hi6220_peripheral_deassert,
+};
+
+static int hi6220_media_assert(struct reset_controller_dev *rc_dev,
+			       unsigned long idx)
 {
 	struct hi6220_reset_data *data = to_reset_data(rc_dev);
+	struct regmap *regmap = data->regmap;
 
-	int bank = idx >> 8;
-	int offset = idx & 0xff;
+	return regmap_write(regmap, SC_MEDIA_RSTEN, BIT(idx));
+}
 
-	writel(BIT(offset), data->deassert_base + (bank * 0x10));
+static int hi6220_media_deassert(struct reset_controller_dev *rc_dev,
+				 unsigned long idx)
+{
+	struct hi6220_reset_data *data = to_reset_data(rc_dev);
+	struct regmap *regmap = data->regmap;
 
-	return 0;
+	return regmap_write(regmap, SC_MEDIA_RSTDIS, BIT(idx));
 }
 
-static const struct reset_control_ops hi6220_reset_ops = {
-	.assert = hi6220_reset_assert,
-	.deassert = hi6220_reset_deassert,
+static const struct reset_control_ops hi6220_media_reset_ops = {
+	.assert = hi6220_media_assert,
+	.deassert = hi6220_media_deassert,
 };
 
 static int hi6220_reset_probe(struct platform_device *pdev)
 {
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	enum hi6220_reset_ctrl_type type;
 	struct hi6220_reset_data *data;
-	struct resource *res;
-	void __iomem *src_base;
+	struct regmap *regmap;
 
-	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	src_base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(src_base))
-		return PTR_ERR(src_base);
+	type = (enum hi6220_reset_ctrl_type)of_device_get_match_data(dev);
+
+	regmap = syscon_node_to_regmap(np);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "failed to get reset controller regmap\n");
+		return PTR_ERR(regmap);
+	}
 
-	data->assert_base = src_base + ASSERT_OFFSET;
-	data->deassert_base = src_base + DEASSERT_OFFSET;
-	data->rc_dev.nr_resets = MAX_INDEX;
-	data->rc_dev.ops = &hi6220_reset_ops;
-	data->rc_dev.of_node = pdev->dev.of_node;
+	data->regmap = regmap;
+	data->rc_dev.of_node = np;
+	if (type == MEDIA) {
+		data->rc_dev.ops = &hi6220_media_reset_ops;
+		data->rc_dev.nr_resets = MEDIA_MAX_INDEX;
+	} else {
+		data->rc_dev.ops = &hi6220_peripheral_reset_ops;
+		data->rc_dev.nr_resets = PERIPH_MAX_INDEX;
+	}
 
 	return reset_controller_register(&data->rc_dev);
 }
 
 static const struct of_device_id hi6220_reset_match[] = {
-	{ .compatible = "hisilicon,hi6220-sysctrl" },
-	{ },
+	{
+		.compatible = "hisilicon,hi6220-sysctrl",
+		.data = (void *)PERIPHERAL,
+	},
+	{
+		.compatible = "hisilicon,hi6220-mediactrl",
+		.data = (void *)MEDIA,
+	},
+	{ /* sentinel */ },
 };
+MODULE_DEVICE_TABLE(of, hi6220_reset_match);
 
 static struct platform_driver hi6220_reset_driver = {
 	.probe = hi6220_reset_probe,

drivers/reset/reset-ti-syscon.c

+/*
+ * TI SYSCON regmap reset driver
+ *
+ * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
+ *	Andrew F. Davis <afd@ti.com>
+ *	Suman Anna <afd@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#include <dt-bindings/reset/ti-syscon.h>
+
+/**
+ * struct ti_syscon_reset_control - reset control structure
+ * @assert_offset: reset assert control register offset from syscon base
+ * @assert_bit: reset assert bit in the reset assert control register
+ * @deassert_offset: reset deassert control register offset from syscon base
+ * @deassert_bit: reset deassert bit in the reset deassert control register
+ * @status_offset: reset status register offset from syscon base
+ * @status_bit: reset status bit in the reset status register
+ * @flags: reset flag indicating how the (de)assert and status are handled
+ */
+struct ti_syscon_reset_control {
+	unsigned int assert_offset;
+	unsigned int assert_bit;
+	unsigned int deassert_offset;
+	unsigned int deassert_bit;
+	unsigned int status_offset;
+	unsigned int status_bit;
+	u32 flags;
+};
+
+/**
+ * struct ti_syscon_reset_data - reset controller information structure
+ * @rcdev: reset controller entity
+ * @regmap: regmap handle containing the memory-mapped reset registers
+ * @controls: array of reset controls
+ * @nr_controls: number of controls in control array
+ */
+struct ti_syscon_reset_data {
+	struct reset_controller_dev rcdev;
+	struct regmap *regmap;
+	struct ti_syscon_reset_control *controls;
+	unsigned int nr_controls;
+};
+
+#define to_ti_syscon_reset_data(rcdev)	\
+	container_of(rcdev, struct ti_syscon_reset_data, rcdev)
+
+/**
+ * ti_syscon_reset_assert() - assert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to be asserted
+ *
+ * This function implements the reset driver op to assert a device's reset.
+ * This asserts the reset in a manner prescribed by the reset flags.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_syscon_reset_assert(struct reset_controller_dev *rcdev,
+				  unsigned long id)
+{
+	struct ti_syscon_reset_data *data = to_ti_syscon_reset_data(rcdev);
+	struct ti_syscon_reset_control *control;
+	unsigned int mask, value;
+
+	if (id >= data->nr_controls)
+		return -EINVAL;
+
+	control = &data->controls[id];
+
+	if (control->flags & ASSERT_NONE)
+		return -ENOTSUPP; /* assert not supported for this reset */
+
+	mask = BIT(control->assert_bit);
+	value = (control->flags & ASSERT_SET) ? mask : 0x0;
+
+	return regmap_update_bits(data->regmap, control->assert_offset, mask, value);
+}
+
+/**
+ * ti_syscon_reset_deassert() - deassert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of reset to be deasserted
+ *
+ * This function implements the reset driver op to deassert a device's reset.
+ * This deasserts the reset in a manner prescribed by the reset flags.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_syscon_reset_deassert(struct reset_controller_dev *rcdev,
+				    unsigned long id)
+{
+	struct ti_syscon_reset_data *data = to_ti_syscon_reset_data(rcdev);
+	struct ti_syscon_reset_control *control;
+	unsigned int mask, value;
+
+	if (id >= data->nr_controls)
+		return -EINVAL;
+
+	control = &data->controls[id];
+
+	if (control->flags & DEASSERT_NONE)
+		return -ENOTSUPP; /* deassert not supported for this reset */
+
+	mask = BIT(control->deassert_bit);
+	value = (control->flags & DEASSERT_SET) ? mask : 0x0;
+
+	return regmap_update_bits(data->regmap, control->deassert_offset, mask, value);
+}
+
+/**
+ * ti_syscon_reset_status() - check device reset status
+ * @rcdev: reset controller entity
+ * @id: ID of the reset for which the status is being requested
+ *
+ * This function implements the reset driver op to return the status of a
+ * device's reset.
+ *
+ * Return: 0 if reset is deasserted, true if reset is asserted, else a
+ * corresponding error value
+ */
+static int ti_syscon_reset_status(struct reset_controller_dev *rcdev,
+				  unsigned long id)
+{
+	struct ti_syscon_reset_data *data = to_ti_syscon_reset_data(rcdev);
+	struct ti_syscon_reset_control *control;
+	unsigned int reset_state;
+	int ret;
+
+	if (id >= data->nr_controls)
+		return -EINVAL;
+
+	control = &data->controls[id];
+
+	if (control->flags & STATUS_NONE)
+		return -ENOTSUPP; /* status not supported for this reset */
+
+	ret = regmap_read(data->regmap, control->status_offset, &reset_state);
+	if (ret)
+		return ret;
+
+	return (reset_state & BIT(control->status_bit)) &&
+			(control->flags & STATUS_SET);
+}
+
+static struct reset_control_ops ti_syscon_reset_ops = {
+	.assert		= ti_syscon_reset_assert,
+	.deassert	= ti_syscon_reset_deassert,
+	.status		= ti_syscon_reset_status,
+};
+
+static int ti_syscon_reset_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct ti_syscon_reset_data *data;
+	struct regmap *regmap;
+	const __be32 *list;
+	struct ti_syscon_reset_control *controls;
+	int size, nr_controls, i;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	regmap = syscon_node_to_regmap(np->parent);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	list = of_get_property(np, "ti,reset-bits", &size);
+	if (!list || (size / sizeof(*list)) % 7 != 0) {
+		dev_err(dev, "invalid DT reset description\n");
+		return -EINVAL;
+	}
+
+	nr_controls = (size / sizeof(*list)) / 7;
+	controls = devm_kzalloc(dev, nr_controls * sizeof(*controls), GFP_KERNEL);
+	if (!controls)
+		return -ENOMEM;
+
+	for (i = 0; i < nr_controls; i++) {
+		controls[i].assert_offset = be32_to_cpup(list++);
+		controls[i].assert_bit = be32_to_cpup(list++);
+		controls[i].deassert_offset = be32_to_cpup(list++);
+		controls[i].deassert_bit = be32_to_cpup(list++);
+		controls[i].status_offset = be32_to_cpup(list++);
+		controls[i].status_bit = be32_to_cpup(list++);
+		controls[i].flags = be32_to_cpup(list++);
+	}
+
+	data->rcdev.ops = &ti_syscon_reset_ops;
+	data->rcdev.owner = THIS_MODULE;
+	data->rcdev.of_node = np;
+	data->rcdev.nr_resets = nr_controls;
+	data->regmap = regmap;
+	data->controls = controls;
+	data->nr_controls = nr_controls;
+
+	platform_set_drvdata(pdev, data);
+
+	return devm_reset_controller_register(dev, &data->rcdev);
+}
+
+static const struct of_device_id ti_syscon_reset_of_match[] = {
+	{ .compatible = "ti,syscon-reset", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_syscon_reset_of_match);
+
+static struct platform_driver ti_syscon_reset_driver = {
+	.probe = ti_syscon_reset_probe,
+	.driver = {
+		.name = "ti-syscon-reset",
+		.of_match_table = ti_syscon_reset_of_match,
+	},
+};
+module_platform_driver(ti_syscon_reset_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
+MODULE_DESCRIPTION("TI SYSCON Regmap Reset Driver");
+MODULE_LICENSE("GPL v2");

include/dt-bindings/reset/hisi,hi6220-resets.h

@@ -64,4 +64,12 @@
 #define PERIPH_RSDIST9_CARM_SOCDBG      0x507
 #define PERIPH_RSDIST9_CARM_ETM         0x508
 
+#define MEDIA_G3D                       0
+#define MEDIA_CODEC_VPU                 2
+#define MEDIA_CODEC_JPEG                3
+#define MEDIA_ISP                       4
+#define MEDIA_ADE                       5
+#define MEDIA_MMU                       6
+#define MEDIA_XG2RAM1                   7
+
 #endif /*_DT_BINDINGS_RESET_CONTROLLER_HI6220*/

include/dt-bindings/reset/ti-syscon.h

+/*
+ * TI Syscon Reset definitions
+ *
+ * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __DT_BINDINGS_RESET_TI_SYSCON_H__
+#define __DT_BINDINGS_RESET_TI_SYSCON_H__
+
+/*
+ * The reset does not support the feature and corresponding
+ * values are not valid
+ */
+#define ASSERT_NONE	(1 << 0)
+#define DEASSERT_NONE	(1 << 1)
+#define STATUS_NONE	(1 << 2)
+
+/* When set this function is activated by setting(vs clearing) this bit */
+#define ASSERT_SET	(1 << 3)
+#define DEASSERT_SET	(1 << 4)
+#define STATUS_SET	(1 << 5)
+
+/* The following are the inverse of the above and are added for consistency */
+#define ASSERT_CLEAR	(0 << 3)
+#define DEASSERT_CLEAR	(0 << 4)
+#define STATUS_CLEAR	(0 << 5)
+
+#endif