[PATCH (v2) 1/2] reset: Add brcm,bcm6345-reset device tree binding

[PATCH (v2) 1/2] reset: Add brcm,bcm6345-reset device tree binding

[Simon Arlott]

Add device tree binding for the BCM6345 soft reset controller.

The BCM6345 contains a soft-reset controller activated by setting
a bit (that must previously have cleared).

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
---
Renamed to bcm6345, removed "mask" property.

 .../bindings/reset/brcm,bcm6345-reset.txt          | 33 ++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt

diff --git a/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
new file mode 100644
index 0000000..bb9ca6e
--- /dev/null
+++ b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
@@ -0,0 +1,33 @@
+Broadcom BCM6345 reset controller
+
+The BCM6345 contains a basic soft reset controller in the perf register
+set which resets components using a bit in a register.
+
+Please also refer to reset.txt in this directory for common reset
+controller binding usage.
+
+Required properties:
+- compatible:	Should be "brcm,bcm<soc>-reset", "brcm,bcm6345-reset"
+- regmap:	The register map phandle
+- offset:	Offset in the register map for the reset register (in bytes)
+- #reset-cells:	Must be set to 1
+
+Example:
+
+periph_soft_rst: reset-controller {
+	compatible = "brcm,bcm63168-reset", "brcm,bcm6345-reset";
+	regmap = <&periph_cntl>;
+	offset = <0x10>;
+
+	#reset-cells = <1>;
+};
+
+usbh: usbphy@10002700 {
+	compatible = "brcm,bcm63168-usbh";
+	reg = <0x10002700 0x38>;
+	clocks = <&periph_clk 13>, <&timer_clk 18>;
+	resets = <&periph_soft_rst 6>;
+	power-supply = <&power_usbh>;
+	#phy-cells = <0>;
+};
+
-- 
2.1.4

-- 
Simon Arlott

[PATCH (v2) 2/2] reset: bcm6345: Add support for the BCM6345 soft-reset controller

[Simon Arlott]

The BCM6345 contains a soft-reset controller activated by setting
a bit (that must previously have cleared).

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
---
 MAINTAINERS                       |   1 +
 drivers/reset/Kconfig             |   1 +
 drivers/reset/Makefile            |  17 +++---
 drivers/reset/bcm/Kconfig         |  10 ++++
 drivers/reset/bcm/Makefile        |   1 +
 drivers/reset/bcm/reset-bcm6345.c | 109 ++++++++++++++++++++++++++++++++++++++
 6 files changed, 131 insertions(+), 8 deletions(-)
 create mode 100644 drivers/reset/bcm/Kconfig
 create mode 100644 drivers/reset/bcm/Makefile
 create mode 100644 drivers/reset/bcm/reset-bcm6345.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 07613dd..a20cecf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2378,6 +2378,7 @@ F:	drivers/irqchip/irq-bcm63*
 F:	drivers/irqchip/irq-bcm7*
 F:	drivers/irqchip/irq-brcmstb*
 F:	drivers/regulator/bcm63*
+F:	drivers/reset/bcm/reset-bcm6345*
 F:	include/linux/bcm63xx_wdt.h
 
 BROADCOM TG3 GIGABIT ETHERNET DRIVER
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 0615f50..ee73f5f 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -12,4 +12,5 @@ menuconfig RESET_CONTROLLER
 
 	  If unsure, say no.
 
+source "drivers/reset/bcm/Kconfig"
 source "drivers/reset/sti/Kconfig"
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 85d5904..a34f469 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -1,8 +1,9 @@
-obj-$(CONFIG_RESET_CONTROLLER) += core.o
-obj-$(CONFIG_ARCH_LPC18XX) += reset-lpc18xx.o
-obj-$(CONFIG_ARCH_SOCFPGA) += reset-socfpga.o
-obj-$(CONFIG_ARCH_BERLIN) += reset-berlin.o
-obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o
-obj-$(CONFIG_ARCH_STI) += sti/
-obj-$(CONFIG_ARCH_ZYNQ) += reset-zynq.o
-obj-$(CONFIG_ATH79) += reset-ath79.o
+obj-$(CONFIG_RESET_CONTROLLER)	+= core.o
+obj-$(CONFIG_ARCH_LPC18XX)	+= reset-lpc18xx.o
+obj-$(CONFIG_ARCH_SOCFPGA)	+= reset-socfpga.o
+obj-$(CONFIG_ARCH_BERLIN)	+= reset-berlin.o
+obj-$(CONFIG_ARCH_SUNXI)	+= reset-sunxi.o
+obj-$(CONFIG_ARCH_STI)		+= sti/
+obj-$(CONFIG_ARCH_ZYNQ)		+= reset-zynq.o
+obj-$(CONFIG_ATH79)		+= reset-ath79.o
+obj-y				+= bcm/
diff --git a/drivers/reset/bcm/Kconfig b/drivers/reset/bcm/Kconfig
new file mode 100644
index 0000000..85931c9
--- /dev/null
+++ b/drivers/reset/bcm/Kconfig
@@ -0,0 +1,10 @@
+if RESET_CONTROLLER
+
+config RESET_BCM6345
+	bool "BCM6345 Reset Controller"
+	depends on BMIPS_GENERIC
+	default BMIPS_GENERIC
+	help
+	  Support resetting of devices on BCM6345 boards.
+
+endif
diff --git a/drivers/reset/bcm/Makefile b/drivers/reset/bcm/Makefile
new file mode 100644
index 0000000..3d004bd
--- /dev/null
+++ b/drivers/reset/bcm/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_RESET_BCM6345)	+= reset-bcm6345.o
diff --git a/drivers/reset/bcm/reset-bcm6345.c b/drivers/reset/bcm/reset-bcm6345.c
new file mode 100644
index 0000000..a95433d
--- /dev/null
+++ b/drivers/reset/bcm/reset-bcm6345.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright 2015 Simon Arlott
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * Derived from reset-berlin.c:
+ * Copyright (C) 2014 Marvell Technology Group Ltd.
+ *
+ * Antoine Tenart <antoine.tenart@free-electrons.com>
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define to_bcm6345_reset_priv(p) \
+		container_of((p), struct bcm6345_reset_priv, rcdev)
+
+struct bcm6345_reset_priv {
+	struct regmap *map;
+	u32 offset;
+	struct reset_controller_dev rcdev;
+	struct mutex mutex;
+};
+
+static int bcm6345_reset_reset(struct reset_controller_dev *rcdev,
+	unsigned long id)
+{
+	struct bcm6345_reset_priv *priv = to_bcm6345_reset_priv(rcdev);
+
+	mutex_lock(&priv->mutex);
+	regmap_write_bits(priv->map, priv->offset, BIT(id), 0);
+	usleep_range(10000, 20000);
+	regmap_write_bits(priv->map, priv->offset, BIT(id), BIT(id));
+	usleep_range(10000, 20000);
+	mutex_unlock(&priv->mutex);
+
+	return 0;
+}
+
+static struct reset_control_ops bcm6345_reset_ops = {
+	.reset = bcm6345_reset_reset,
+};
+
+static int __init bcm6345_reset_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct bcm6345_reset_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mutex_init(&priv->mutex);
+
+	priv->map = syscon_regmap_lookup_by_phandle(np, "regmap");
+	if (IS_ERR(priv->map))
+		return PTR_ERR(priv->map);
+
+	if (of_property_read_u32(np, "offset", &priv->offset))
+		return -EINVAL;
+
+	priv->rcdev.owner = THIS_MODULE;
+	priv->rcdev.ops = &bcm6345_reset_ops;
+	priv->rcdev.nr_resets = 32;
+	priv->rcdev.of_node = pdev->dev.of_node;
+
+	ret = reset_controller_register(&priv->rcdev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"unable to register reset controller: %d\n", ret);
+		return ret;
+	}
+
+	dev_info(&pdev->dev, "registered reset controller\n");
+	return 0;
+}
+
+static const struct of_device_id bcm6345_reset_dt_match[] __initconst = {
+	{ .compatible = "brcm,bcm6345-reset" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, bcm6345_reset_dt_match);
+
+static struct platform_driver bcm6345_reset_driver __refdata = {
+	.probe	= bcm6345_reset_probe,
+	.driver	= {
+		.name = "bcm6345-reset",
+		.of_match_table = bcm6345_reset_dt_match,
+	},
+};
+module_platform_driver(bcm6345_reset_driver);
+
+MODULE_DESCRIPTION("BCM6345 reset driver");
+MODULE_AUTHOR("Simon Arlott");
+MODULE_LICENSE("GPL");
-- 
2.1.4

-- 
Simon Arlott

Re: [PATCH (v2) 1/2] reset: Add brcm,bcm6345-reset device tree binding

[Philipp Zabel]

Hi Simon,

Am Mittwoch, den 02.12.2015, 21:03 +0000 schrieb Simon Arlott:
> Add device tree binding for the BCM6345 soft reset controller.
> 
> The BCM6345 contains a soft-reset controller activated by setting
> a bit (that must previously have cleared).
> 
> Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
> ---
> Renamed to bcm6345, removed "mask" property.
> 
>  .../bindings/reset/brcm,bcm6345-reset.txt          | 33 ++++++++++++++++++++++
>  1 file changed, 33 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> 
> diff --git a/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> new file mode 100644
> index 0000000..bb9ca6e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> @@ -0,0 +1,33 @@
> +Broadcom BCM6345 reset controller
> +
> +The BCM6345 contains a basic soft reset controller in the perf register
> +set which resets components using a bit in a register.
> +
> +Please also refer to reset.txt in this directory for common reset
> +controller binding usage.
> +
> +Required properties:
> +- compatible:	Should be "brcm,bcm<soc>-reset", "brcm,bcm6345-reset"

> +- regmap:	The register map phandle
> +- offset:	Offset in the register map for the reset register (in bytes)

Is this something the device tree maintainers are happy with?
I see there are already some regmap properties in the device tree, but
in this case it looks to me like the reset controller node should be a
child of the periph_cntl node as that register space is the only means
of controlling it.

> +- #reset-cells:	Must be set to 1
> +
> +Example:
> +
> +periph_soft_rst: reset-controller {
> +	compatible = "brcm,bcm63168-reset", "brcm,bcm6345-reset";
> +	regmap = <&periph_cntl>;
> +	offset = <0x10>;
> +
> +	#reset-cells = <1>;
> +};

I would have written it something like this:

periph_cntl: ... {
	compatible = "syscon", "simple-mfd";
	#address-cells = <1>;
	#size-cells = <1>;

	periph_soft_rst: reset-controller {
		compatible = "brcm,bcm6345-reset";
		reg = <0x10 0x4>;
		#reset-cells = <1>;
	};
};

for a device that is only controlled through a syscon.
The driver itself looks good to me.

best regards
Philipp

Re: [PATCH (v2) 1/2] reset: Add brcm,bcm6345-reset device tree binding

[Rob Herring]

On Wed, Dec 02, 2015 at 09:03:18PM +0000, Simon Arlott wrote:
> Add device tree binding for the BCM6345 soft reset controller.
> 
> The BCM6345 contains a soft-reset controller activated by setting
> a bit (that must previously have cleared).
> 
> Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
> ---
> Renamed to bcm6345, removed "mask" property.

Acked-by: Rob Herring <robh@kernel.org>

> 
>  .../bindings/reset/brcm,bcm6345-reset.txt          | 33 ++++++++++++++++++++++
>  1 file changed, 33 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> 
> diff --git a/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> new file mode 100644
> index 0000000..bb9ca6e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/brcm,bcm6345-reset.txt
> @@ -0,0 +1,33 @@
> +Broadcom BCM6345 reset controller
> +
> +The BCM6345 contains a basic soft reset controller in the perf register
> +set which resets components using a bit in a register.
> +
> +Please also refer to reset.txt in this directory for common reset
> +controller binding usage.
> +
> +Required properties:
> +- compatible:	Should be "brcm,bcm<soc>-reset", "brcm,bcm6345-reset"
> +- regmap:	The register map phandle
> +- offset:	Offset in the register map for the reset register (in bytes)
> +- #reset-cells:	Must be set to 1
> +
> +Example:
> +
> +periph_soft_rst: reset-controller {
> +	compatible = "brcm,bcm63168-reset", "brcm,bcm6345-reset";
> +	regmap = <&periph_cntl>;
> +	offset = <0x10>;
> +
> +	#reset-cells = <1>;
> +};
> +
> +usbh: usbphy@10002700 {
> +	compatible = "brcm,bcm63168-usbh";
> +	reg = <0x10002700 0x38>;
> +	clocks = <&periph_clk 13>, <&timer_clk 18>;
> +	resets = <&periph_soft_rst 6>;
> +	power-supply = <&power_usbh>;
> +	#phy-cells = <0>;
> +};
> +
> -- 
> 2.1.4
> 
> -- 
> Simon Arlott

Re: [PATCH (v2) 1/2] reset: Add brcm,bcm6345-reset device tree binding

[Simon Arlott]

On Thu, December 3, 2015 08:39, Philipp Zabel wrote:
> Am Mittwoch, den 02.12.2015, 21:03 +0000 schrieb Simon Arlott:
>> +periph_soft_rst: reset-controller {
>> +	compatible = "brcm,bcm63168-reset", "brcm,bcm6345-reset";
>> +	regmap = <&periph_cntl>;
>> +	offset = <0x10>;
>> +
>> +	#reset-cells = <1>;
>> +};
>
> I would have written it something like this:
>
> periph_cntl: ... {
> 	compatible = "syscon", "simple-mfd";
> 	#address-cells = <1>;
> 	#size-cells = <1>;
>
> 	periph_soft_rst: reset-controller {
> 		compatible = "brcm,bcm6345-reset";
> 		reg = <0x10 0x4>;
> 		#reset-cells = <1>;
> 	};
> };
>
> for a device that is only controlled through a syscon.

Rob, do you want me to change this or is my version ok?

> The driver itself looks good to me.
>
> best regards
> Philipp
>
>

-- 
Simon Arlott