[PATCH anybus v1 0/4] Support HMS Profinet Card over Anybus

[PATCH anybus v1 0/4] Support HMS Profinet Card over Anybus

[Sven Van Asbroeck]

This patch set adds support for the HMS Industrial Networks AB Profinet card.

Profinet is an industry technical standard for data communication over
Industrial Ethernet, designed for collecting data from, and controlling,
equipment in industrial systems, with a particular strength in delivering data
under tight time constraints (on the order of 1ms or less).

The profinet card itself is connected to the system via an industrial bus
called 'anybus'.

I have followed the bus driver/client driver pattern, and created an anybus
bus driver, plus a client driver for the profinet card.

In case this patch set gets (eventually) accepted, drivers for other anybus
client cards may follow: flnet, cc-link, ...

The anybus slot on the host is located on an 'anybus bridge', which is
custom h/w designed by Arcx. Its driver is modeled as an mfd, which
instantiates two anybus slots.

v1:
	first shot

Sven Van Asbroeck (4):
  mfd: support the Arcx anybus bridge.
  dt-bindings: anybus-bridge: document devicetree binding.
  bus: support HMS Anybus-S bus.
  misc: support HMS Profinet IRT industrial controller.

 .../bindings/mfd/arcx,anybus-bridge.txt       |   37 +
 .../devicetree/bindings/vendor-prefixes.txt   |    1 +
 drivers/bus/Kconfig                           |   11 +
 drivers/bus/Makefile                          |    1 +
 drivers/bus/anybuss-host.c                    | 1301 +++++++++++++++++
 drivers/mfd/Kconfig                           |   11 +
 drivers/mfd/Makefile                          |    1 +
 drivers/mfd/anybus-bridge.c                   |  441 ++++++
 drivers/misc/Kconfig                          |   11 +
 drivers/misc/Makefile                         |    1 +
 drivers/misc/hms-profinet.c                   |  747 ++++++++++
 include/linux/anybuss-client.h                |  100 ++
 include/linux/anybuss-host.h                  |   28 +
 include/uapi/linux/hms-common.h               |   14 +
 include/uapi/linux/hms-profinet.h             |  101 ++
 15 files changed, 2806 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
 create mode 100644 drivers/bus/anybuss-host.c
 create mode 100644 drivers/mfd/anybus-bridge.c
 create mode 100644 drivers/misc/hms-profinet.c
 create mode 100644 include/linux/anybuss-client.h
 create mode 100644 include/linux/anybuss-host.h
 create mode 100644 include/uapi/linux/hms-common.h
 create mode 100644 include/uapi/linux/hms-profinet.h

-- 
2.17.1

[PATCH anybus v1 1/4] mfd: support the Arcx anybus bridge.

[Sven Van Asbroeck]

Add a driver for the Arcx anybus bridge.

This chip embeds up to two Anybus-S application connectors
(slots), and connects to the SoC via the i.MX parallel WEIM bus.
There is also a CAN power readout, unrelated to the anybus.

Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
---
 drivers/mfd/Kconfig          |  11 +
 drivers/mfd/Makefile         |   1 +
 drivers/mfd/anybus-bridge.c  | 441 +++++++++++++++++++++++++++++++++++
 include/linux/anybuss-host.h |  28 +++
 4 files changed, 481 insertions(+)
 create mode 100644 drivers/mfd/anybus-bridge.c
 create mode 100644 include/linux/anybuss-host.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 11841f4b7b2b..49b9de71cb16 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -125,6 +125,17 @@ config MFD_ATMEL_SMC
 	bool
 	select MFD_SYSCON
 
+config MFD_ANYBUS_BRIDGE
+	tristate "Arcx Anybus-S Bridge"
+	select MFD_CORE
+	select REGMAP
+	depends on OF
+	help
+	  Select this to get support for the Arcx Anybus bridge.
+	  It is accessible via the i.MX parallel WEIM bus, and
+	  embeds up to two Anybus-S application connectors (slots).
+	  There is also a CAN power readout, unrelated to the anybus.
+
 config MFD_BCM590XX
 	tristate "Broadcom BCM590xx PMUs"
 	select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5856a9489cbd..c45075452d40 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -223,6 +223,7 @@ obj-$(CONFIG_MFD_HI655X_PMIC)   += hi655x-pmic.o
 obj-$(CONFIG_MFD_DLN2)		+= dln2.o
 obj-$(CONFIG_MFD_RT5033)	+= rt5033.o
 obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o
+obj-$(CONFIG_MFD_ANYBUS_BRIDGE) += anybus-bridge.o
 
 intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
 obj-$(CONFIG_INTEL_SOC_PMIC)	+= intel-soc-pmic.o
diff --git a/drivers/mfd/anybus-bridge.c b/drivers/mfd/anybus-bridge.c
new file mode 100644
index 000000000000..f6eda5b2b6e8
--- /dev/null
+++ b/drivers/mfd/anybus-bridge.c
@@ -0,0 +1,441 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Arcx Anybus Bridge driver
+ *
+ * Copyright (C) 2018 Arcx Inc
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/of_address.h>
+#include <linux/pwm.h>
+#include <linux/mfd/core.h>
+#include <linux/of_irq.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/idr.h>
+#include <linux/spinlock.h>
+
+#include <linux/anybuss-host.h>
+
+#define CPLD_STATUS1		0x80
+#define CPLD_CONTROL		0x80
+#define CPLD_CONTROL_CRST	0x40
+#define CPLD_CONTROL_RST1	0x04
+#define CPLD_CONTROL_RST2	0x80
+#define CPLD_STATUS1_AB		0x02
+#define CPLD_STATUS1_CAN_POWER	0x01
+#define CPLD_DESIGN_LO		0x81
+#define CPLD_DESIGN_HI		0x82
+#define CPLD_CAP		0x83
+#define CPLD_CAP_COMPAT		0x01
+#define CPLD_CAP_SEP_RESETS	0x02
+
+struct bridge_priv {
+	struct device *class_dev;
+	void __iomem *cpld_base;
+	spinlock_t regs_lock;
+	u8 control_reg;
+	char version[3];
+	u16 design_no;
+};
+
+/* the cpld supports single-byte accesses ONLY */
+
+static int read_reg_weim(void *context, unsigned int reg,
+				unsigned int *val)
+{
+	void __iomem *base = context;
+
+	*val = readb(base + reg);
+	return 0;
+}
+
+static int write_reg_weim(void *context, unsigned int reg,
+				unsigned int val)
+{
+	void __iomem *base = context;
+
+	writeb(val, base + reg);
+	return 0;
+}
+
+static struct regmap *create_weim_regmap(struct device *dev,
+			struct resource *res, int slot)
+{
+	struct regmap_config regmap_cfg = {
+		.reg_bits = 11,
+		.val_bits = 8,
+		/* bus accesses are simple weim byte accesses.
+		 * they don't require any synchronization.
+		 * also, the bus driver requirement is that regmap accesses
+		 * must never sleep.
+		 */
+		.disable_locking = true,
+		.reg_read = read_reg_weim,
+		.reg_write = write_reg_weim,
+	};
+	void __iomem *base;
+	char name[32];
+
+	if (resource_size(res) < (1<<regmap_cfg.reg_bits))
+		return ERR_PTR(-EINVAL);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return (struct regmap *)base;
+	/* give the regmap a name, so it shows up in debugfs */
+	snprintf(name, sizeof(name), "slot%d", slot);
+	regmap_cfg.name = devm_kmemdup(dev, name, sizeof(name), GFP_KERNEL);
+	if (regmap_cfg.name == NULL)
+		return ERR_PTR(-ENOMEM);
+	return devm_regmap_init(dev, NULL, base, &regmap_cfg);
+}
+
+static int add_anybus_slot(struct device *dev, anybuss_reset_t reset,
+				int slot)
+{
+	int err, irq;
+	struct resource mem_res, *irq_res;
+	struct mfd_cell *cell;
+	struct anybuss_host_pdata *pdata;
+	struct gpio_desc *gpio;
+	struct regmap *regmap;
+
+	/* get irq from devicetree */
+	gpio = devm_gpiod_get_index(dev, "irq", slot, GPIOD_IN);
+	if (IS_ERR(gpio))
+		return PTR_ERR(gpio);
+	irq = gpiod_to_irq(gpio);
+	if (irq < 0) {
+		dev_err(dev, "Anybus-S slot %d: no irq?", slot);
+		return -EINVAL;
+	}
+	/* get anybus mem resource from devicetree
+	 * note that the cpld registers sit at dt offset 0
+	 * anybus slot memory starts at offset 1
+	 */
+	err = of_address_to_resource(dev->of_node, slot+1, &mem_res);
+	if (err) {
+		dev_err(dev, "Anybus-S slot %d: no weim memory?", slot);
+		return err;
+	}
+	regmap = create_weim_regmap(dev, &mem_res, slot);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+	/* add slot as a mfd device */
+	irq_res = devm_kzalloc(dev, sizeof(*irq_res), GFP_KERNEL);
+	if (!irq_res)
+		return -ENOMEM;
+	irq_res->start = irq_res->end = irq;
+	irq_res->flags = IORESOURCE_IRQ;
+	irq_res->name = "anybus-irq";
+	cell = devm_kzalloc(dev, sizeof(*cell), GFP_KERNEL);
+	if (!cell)
+		return -ENOMEM;
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+	pdata->reset = reset;
+	pdata->regmap = regmap;
+	cell->name = "anybuss-host";
+	cell->num_resources = 1;
+	cell->resources = irq_res;
+	cell->platform_data = pdata;
+	cell->pdata_size = sizeof(*pdata);
+	dev_info(dev, "Anybus-S slot %d: [weim 0x%016x-0x%016x] [irq %d]",
+		slot, mem_res.start, mem_res.end, irq);
+	err = devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, cell, 1,
+						NULL, 0, NULL);
+	if (err)
+		dev_err(dev, "failed to add Anybus-S slot %d", slot);
+	return err;
+}
+
+static int add_anybus_slots(struct device *dev, struct device_node *np,
+				anybuss_reset_t *resets)
+{
+	int i, err;
+
+	/* bridge has two Anybus-S slots */
+	for (i = 0; i < 2; i++) {
+		err = add_anybus_slot(dev, resets[i], i);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static void do_reset(struct device *dev, u8 rst_bit, bool reset)
+{
+	unsigned long flags;
+	struct bridge_priv *cd = dev_get_drvdata(dev);
+
+	spin_lock_irqsave(&cd->regs_lock, flags);
+	/* CPLD_CONTROL is write-only, so cache its value in
+	 * cd->control_reg
+	 */
+	if (reset)
+		cd->control_reg &= ~rst_bit;
+	else
+		cd->control_reg |= rst_bit;
+	writeb(cd->control_reg, cd->cpld_base + CPLD_CONTROL);
+	/* h/w work-around:
+	 * EIM bus is 'too fast', so a reset followed by an immediate
+	 * not-reset will _not_ change the anybus reset line in any way,
+	 * losing the reset. to prevent this from happening, introduce
+	 * a minimum reset duration.
+	 * Verified minimum safe duration required using a scope
+	 * on 14-June-2018: 100 us.
+	 */
+	if (reset)
+		udelay(100);
+	spin_unlock_irqrestore(&cd->regs_lock, flags);
+}
+
+static void common_reset(struct device *dev, bool reset)
+{
+	do_reset(dev, CPLD_CONTROL_CRST, reset);
+}
+
+static void ab1_reset(struct device *dev, bool reset)
+{
+	do_reset(dev, CPLD_CONTROL_RST1, reset);
+}
+
+static void ab2_reset(struct device *dev, bool reset)
+{
+	do_reset(dev, CPLD_CONTROL_RST2, reset);
+}
+
+static void create_resets(struct device *dev, u8 cap,
+				anybuss_reset_t *resets)
+{
+	if (cap & CPLD_CAP_SEP_RESETS) {
+		dev_info(dev, "Bridge supports separate resets");
+		resets[0] = ab1_reset;
+		resets[1] = ab2_reset;
+	} else {
+		dev_info(dev, "Bridge supports a common reset");
+		resets[0] = resets[1] = common_reset;
+	}
+}
+
+static ssize_t version_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct bridge_priv *cd = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", cd->version);
+}
+static DEVICE_ATTR_RO(version);
+
+static ssize_t design_number_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct bridge_priv *cd = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", cd->design_no);
+}
+static DEVICE_ATTR_RO(design_number);
+
+static ssize_t can_power_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct bridge_priv *cd = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n",
+		!(readb(cd->cpld_base + CPLD_STATUS1) &
+					CPLD_STATUS1_CAN_POWER));
+}
+static DEVICE_ATTR_RO(can_power);
+
+static struct attribute *bridge_attributes[] = {
+	&dev_attr_version.attr,
+	&dev_attr_design_number.attr,
+	&dev_attr_can_power.attr,
+	NULL,
+};
+
+static struct attribute_group bridge_attribute_group = {
+	.attrs = bridge_attributes,
+};
+
+static const struct attribute_group *bridge_attribute_groups[] = {
+	&bridge_attribute_group,
+	NULL,
+};
+
+static void bridge_device_release(struct device *dev)
+{
+	kfree(dev);
+}
+
+static struct class *bridge_class;
+static DEFINE_IDA(bridge_index_ida);
+
+static int bridge_probe(struct platform_device *pdev)
+{
+	struct bridge_priv *cd;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	int enable_gpio, err, id;
+	struct pwm_device *pwm;
+	struct pwm_args pargs;
+	struct resource res;
+	unsigned int period;
+	u8 status1, cap;
+	anybuss_reset_t resets[2];
+
+	if (!np) {
+		dev_err(dev, "device node not found\n");
+		return -EINVAL;
+	}
+	cd = devm_kzalloc(dev, sizeof(*cd), GFP_KERNEL);
+	if (!cd)
+		return -ENOMEM;
+	dev_set_drvdata(dev, cd);
+	spin_lock_init(&cd->regs_lock);
+	enable_gpio = of_get_named_gpio(np, "enable-gpios", 0);
+	if (!gpio_is_valid(enable_gpio)) {
+		dev_err(dev, "enable-gpios not found\n");
+		return -EINVAL;
+	}
+	devm_gpio_request(dev, enable_gpio, NULL);
+	gpio_direction_output(enable_gpio, 0);
+
+	/* PWM */
+	pwm = devm_pwm_get(dev, NULL);
+	if (IS_ERR(pwm)) {
+		dev_err(dev, "pwm not found\n");
+		return -EINVAL;
+	}
+	pwm_get_args(pwm, &pargs);
+	period = pargs.period;
+	err = pwm_config(pwm, period/2, period);
+	if (err)
+		return err;
+	err = pwm_enable(pwm);
+	if (err)
+		return err;
+
+	/* CPLD control memory, sits at index 0 */
+	if (of_address_to_resource(np, 0, &res)) {
+		dev_err(dev, "cpld base address not found\n");
+		return -EINVAL;
+	}
+	cd->cpld_base = devm_ioremap_resource(dev, &res);
+	if (IS_ERR(cd->cpld_base)) {
+		dev_err(dev,
+			"failed to map cpld base address\n");
+		return PTR_ERR(cd->cpld_base);
+	}
+
+	/* identify cpld */
+	status1 = readb(cd->cpld_base + CPLD_STATUS1);
+	cd->design_no = (__raw_readb(cd->cpld_base + CPLD_DESIGN_HI) << 8) |
+				__raw_readb(cd->cpld_base + CPLD_DESIGN_LO);
+	snprintf(cd->version, sizeof(cd->version), "%c%d",
+			'A' + ((status1>>5) & 0x7),
+			(status1>>2) & 0x7);
+	dev_info(dev, "Bridge is design number %d, revision %s\n",
+		cd->design_no,
+		cd->version);
+	cap = readb(cd->cpld_base + CPLD_CAP);
+	if (!(cap & CPLD_CAP_COMPAT)) {
+		dev_err(dev, "unsupported bridge [cap=0x%02X]", cap);
+		return -ENODEV;
+	}
+
+	if (status1 & CPLD_STATUS1_AB) {
+		dev_info(dev, "Bridge has anybus-S slot(s)");
+		create_resets(dev, cap, resets);
+		err = add_anybus_slots(dev, np, resets);
+		if (err)
+			return err;
+	}
+
+	id = ida_simple_get(&bridge_index_ida, 0, 0, GFP_KERNEL);
+	if (id < 0)
+		return id;
+	/* make bridge info visible to userspace */
+	cd->class_dev = kzalloc(sizeof(*cd->class_dev), GFP_KERNEL);
+	if (!cd->class_dev) {
+		err = -ENOMEM;
+		goto out_ida;
+	}
+	cd->class_dev->class = bridge_class;
+	cd->class_dev->groups = bridge_attribute_groups;
+	cd->class_dev->parent = dev;
+	cd->class_dev->id = id;
+	cd->class_dev->release = bridge_device_release;
+	dev_set_name(cd->class_dev, "bridge%d", cd->class_dev->id);
+	dev_set_drvdata(cd->class_dev, cd);
+	err = device_register(cd->class_dev);
+	if (err)
+		goto out_dev;
+	return 0;
+out_dev:
+	put_device(cd->class_dev);
+out_ida:
+	ida_simple_remove(&bridge_index_ida, id);
+	return err;
+}
+
+static int bridge_remove(struct platform_device *pdev)
+{
+	struct bridge_priv *cd = platform_get_drvdata(pdev);
+	int id = cd->class_dev->id;
+
+	device_unregister(cd->class_dev);
+	ida_simple_remove(&bridge_index_ida, id);
+	return 0;
+}
+
+static const struct of_device_id bridge_of_match[] = {
+	{ .compatible = "arcx,anybus-bridge" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, bridge_of_match);
+
+static struct platform_driver bridge_driver = {
+	.probe = bridge_probe,
+	.remove = bridge_remove,
+	.driver		= {
+		.name   = "arcx-anybus-bridge",
+		.owner	= THIS_MODULE,
+		.of_match_table	= of_match_ptr(bridge_of_match),
+	},
+};
+
+static int __init bridge_init(void)
+{
+	int err;
+
+	bridge_class = class_create(THIS_MODULE, "arcx_anybus_bridge");
+	if (!IS_ERR(bridge_class)) {
+		err = platform_driver_register(&bridge_driver);
+		if (err)
+			class_destroy(bridge_class);
+	} else
+		err = PTR_ERR(bridge_class);
+	return err;
+}
+
+static void __exit bridge_exit(void)
+{
+	platform_driver_unregister(&bridge_driver);
+	class_destroy(bridge_class);
+}
+
+module_init(bridge_init);
+module_exit(bridge_exit);
+
+MODULE_DESCRIPTION("Arcx Anybus Bridge driver");
+MODULE_AUTHOR("Sven Van Asbroeck <svendev@arcx.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/anybuss-host.h b/include/linux/anybuss-host.h
new file mode 100644
index 000000000000..38037833acd4
--- /dev/null
+++ b/include/linux/anybuss-host.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Anybus-S host adapter definitions
+ *
+ * Copyright 2018 Arcx Inc
+ */
+
+#ifndef __LINUX_ANYBUSS_HOST_H__
+#define __LINUX_ANYBUSS_HOST_H__
+
+#include <linux/regmap.h>
+
+typedef void (*anybuss_reset_t)(struct device *dev, bool reset);
+
+/**
+ * Platform data of the Anybus-S host controller.
+ *
+ * @regmap: provides access to the card dpram.
+ *		MUST NOT use caching
+ *		MUST NOT sleep
+ * @reset:  controls the card reset line.
+ */
+struct anybuss_host_pdata {
+	struct regmap *regmap;
+	anybuss_reset_t reset;
+};
+
+#endif /* __LINUX_ANYBUS_S_HOST_H__ */
-- 
2.17.1

[PATCH anybus v1 1/4] mfd: support the Arcx anybus bridge.

[Randy Dunlap]

Hi-

On 10/24/18 7:24 AM, Sven Van Asbroeck wrote:
> Add a driver for the Arcx anybus bridge.
> 
> This chip embeds up to two Anybus-S application connectors
> (slots), and connects to the SoC via the i.MX parallel WEIM bus.
> There is also a CAN power readout, unrelated to the anybus.
> 
> Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
> ---
>  drivers/mfd/Kconfig          |  11 +
>  drivers/mfd/Makefile         |   1 +
>  drivers/mfd/anybus-bridge.c  | 441 +++++++++++++++++++++++++++++++++++
>  include/linux/anybuss-host.h |  28 +++
>  4 files changed, 481 insertions(+)
>  create mode 100644 drivers/mfd/anybus-bridge.c
>  create mode 100644 include/linux/anybuss-host.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 11841f4b7b2b..49b9de71cb16 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -125,6 +125,17 @@ config MFD_ATMEL_SMC
>  	bool
>  	select MFD_SYSCON
>  
> +config MFD_ANYBUS_BRIDGE
> +	tristate "Arcx Anybus-S Bridge"
> +	select MFD_CORE
> +	select REGMAP
> +	depends on OF
> +	help
> +	  Select this to get support for the Arcx Anybus bridge.
> +	  It is accessible via the i.MX parallel WEIM bus, and
> +	  embeds up to two Anybus-S application connectors (slots).
> +	  There is also a CAN power readout, unrelated to the anybus.

	                                                      Anybus.

> +
>  config MFD_BCM590XX
>  	tristate "Broadcom BCM590xx PMUs"
>  	select MFD_CORE

> diff --git a/drivers/mfd/anybus-bridge.c b/drivers/mfd/anybus-bridge.c
> new file mode 100644
> index 000000000000..f6eda5b2b6e8
> --- /dev/null
> +++ b/drivers/mfd/anybus-bridge.c
> @@ -0,0 +1,441 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Arcx Anybus Bridge driver
> + *
> + * Copyright (C) 2018 Arcx Inc
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/platform_device.h>
> +#include <linux/gpio.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_address.h>
> +#include <linux/pwm.h>
> +#include <linux/mfd/core.h>
> +#include <linux/of_irq.h>
> +#include <linux/delay.h>
> +#include <linux/regmap.h>
> +#include <linux/idr.h>
> +#include <linux/spinlock.h>
> +
> +#include <linux/anybuss-host.h>
> +

[snip]

> +
> +static struct regmap *create_weim_regmap(struct device *dev,
> +			struct resource *res, int slot)
> +{
> +	struct regmap_config regmap_cfg = {
> +		.reg_bits = 11,
> +		.val_bits = 8,
> +		/* bus accesses are simple weim byte accesses.

		                           WEIM

> +		 * they don't require any synchronization.
> +		 * also, the bus driver requirement is that regmap accesses
> +		 * must never sleep.
> +		 */

Kernel multi-line comment style (except in networking code) is like:
		/*
		 * bus accesses are ...
		 * must never sleep.
		 */

> +		.disable_locking = true,
> +		.reg_read = read_reg_weim,
> +		.reg_write = write_reg_weim,
> +	};
> +	void __iomem *base;
> +	char name[32];
> +
> +	if (resource_size(res) < (1<<regmap_cfg.reg_bits))
> +		return ERR_PTR(-EINVAL);
> +	base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(base))
> +		return (struct regmap *)base;
> +	/* give the regmap a name, so it shows up in debugfs */
> +	snprintf(name, sizeof(name), "slot%d", slot);
> +	regmap_cfg.name = devm_kmemdup(dev, name, sizeof(name), GFP_KERNEL);
> +	if (regmap_cfg.name == NULL)
> +		return ERR_PTR(-ENOMEM);
> +	return devm_regmap_init(dev, NULL, base, &regmap_cfg);
> +}
> +
> +static int add_anybus_slot(struct device *dev, anybuss_reset_t reset,
> +				int slot)
> +{
> +	int err, irq;
> +	struct resource mem_res, *irq_res;
> +	struct mfd_cell *cell;
> +	struct anybuss_host_pdata *pdata;
> +	struct gpio_desc *gpio;
> +	struct regmap *regmap;
> +
> +	/* get irq from devicetree */
> +	gpio = devm_gpiod_get_index(dev, "irq", slot, GPIOD_IN);
> +	if (IS_ERR(gpio))
> +		return PTR_ERR(gpio);
> +	irq = gpiod_to_irq(gpio);
> +	if (irq < 0) {
> +		dev_err(dev, "Anybus-S slot %d: no irq?", slot);
> +		return -EINVAL;
> +	}
> +	/* get anybus mem resource from devicetree
> +	 * note that the cpld registers sit at dt offset 0
> +	 * anybus slot memory starts at offset 1
> +	 */

comment style.

> +	err = of_address_to_resource(dev->of_node, slot+1, &mem_res);
> +	if (err) {
> +		dev_err(dev, "Anybus-S slot %d: no weim memory?", slot);
> +		return err;
> +	}
> +	regmap = create_weim_regmap(dev, &mem_res, slot);
> +	if (IS_ERR(regmap))
> +		return PTR_ERR(regmap);
> +	/* add slot as a mfd device */
> +	irq_res = devm_kzalloc(dev, sizeof(*irq_res), GFP_KERNEL);
> +	if (!irq_res)
> +		return -ENOMEM;
> +	irq_res->start = irq_res->end = irq;
> +	irq_res->flags = IORESOURCE_IRQ;
> +	irq_res->name = "anybus-irq";
> +	cell = devm_kzalloc(dev, sizeof(*cell), GFP_KERNEL);
> +	if (!cell)
> +		return -ENOMEM;
> +	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata)
> +		return -ENOMEM;
> +	pdata->reset = reset;
> +	pdata->regmap = regmap;
> +	cell->name = "anybuss-host";
> +	cell->num_resources = 1;
> +	cell->resources = irq_res;
> +	cell->platform_data = pdata;
> +	cell->pdata_size = sizeof(*pdata);
> +	dev_info(dev, "Anybus-S slot %d: [weim 0x%016x-0x%016x] [irq %d]",
> +		slot, mem_res.start, mem_res.end, irq);
> +	err = devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, cell, 1,
> +						NULL, 0, NULL);
> +	if (err)
> +		dev_err(dev, "failed to add Anybus-S slot %d", slot);
> +	return err;
> +}
> +
> +static int add_anybus_slots(struct device *dev, struct device_node *np,
> +				anybuss_reset_t *resets)
> +{
> +	int i, err;
> +
> +	/* bridge has two Anybus-S slots */
> +	for (i = 0; i < 2; i++) {
> +		err = add_anybus_slot(dev, resets[i], i);
> +		if (err)
> +			return err;
> +	}
> +	return 0;
> +}
> +
> +static void do_reset(struct device *dev, u8 rst_bit, bool reset)
> +{
> +	unsigned long flags;
> +	struct bridge_priv *cd = dev_get_drvdata(dev);
> +
> +	spin_lock_irqsave(&cd->regs_lock, flags);
> +	/* CPLD_CONTROL is write-only, so cache its value in
> +	 * cd->control_reg
> +	 */

comment style.

> +	if (reset)
> +		cd->control_reg &= ~rst_bit;
> +	else
> +		cd->control_reg |= rst_bit;
> +	writeb(cd->control_reg, cd->cpld_base + CPLD_CONTROL);
> +	/* h/w work-around:
> +	 * EIM bus is 'too fast', so a reset followed by an immediate
> +	 * not-reset will _not_ change the anybus reset line in any way,
> +	 * losing the reset. to prevent this from happening, introduce
> +	 * a minimum reset duration.
> +	 * Verified minimum safe duration required using a scope
> +	 * on 14-June-2018: 100 us.
> +	 */

comment style.

> +	if (reset)
> +		udelay(100);
> +	spin_unlock_irqrestore(&cd->regs_lock, flags);
> +}
> +

> diff --git a/include/linux/anybuss-host.h b/include/linux/anybuss-host.h
> new file mode 100644
> index 000000000000..38037833acd4
> --- /dev/null
> +++ b/include/linux/anybuss-host.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Anybus-S host adapter definitions
> + *
> + * Copyright 2018 Arcx Inc
> + */
> +
> +#ifndef __LINUX_ANYBUSS_HOST_H__
> +#define __LINUX_ANYBUSS_HOST_H__
> +
> +#include <linux/regmap.h>
> +
> +typedef void (*anybuss_reset_t)(struct device *dev, bool reset);
> +
> +/**
> + * Platform data of the Anybus-S host controller.

    * struct anybuss_host_pdata - Platform data of the Anybus-S host controller.

to convert this comment block to kernel-doc notation.

> + *
> + * @regmap: provides access to the card dpram.
> + *		MUST NOT use caching
> + *		MUST NOT sleep
> + * @reset:  controls the card reset line.
> + */> +struct anybuss_host_pdata {
> +	struct regmap *regmap;
> +	anybuss_reset_t reset;
> +};
> +
> +#endif /* __LINUX_ANYBUS_S_HOST_H__ */
> 


-- 
~Randy

Re: [PATCH anybus v1 1/4] mfd: support the Arcx anybus bridge.

[Lee Jones]

On Wed, 24 Oct 2018, Sven Van Asbroeck wrote:

> Add a driver for the Arcx anybus bridge.
> 
> This chip embeds up to two Anybus-S application connectors
> (slots), and connects to the SoC via the i.MX parallel WEIM bus.
> There is also a CAN power readout, unrelated to the anybus.
> 
> Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
> ---
>  drivers/mfd/Kconfig          |  11 +
>  drivers/mfd/Makefile         |   1 +
>  drivers/mfd/anybus-bridge.c  | 441 +++++++++++++++++++++++++++++++++++
>  include/linux/anybuss-host.h |  28 +++
>  4 files changed, 481 insertions(+)
>  create mode 100644 drivers/mfd/anybus-bridge.c
>  create mode 100644 include/linux/anybuss-host.h

Wow, this driver is going to need a lot of work.

But before we get going, how many sub-devices does this have?

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH anybus v1 1/4] mfd: support the Arcx anybus bridge.

[Sven Van Asbroeck]

> Wow, this driver is going to need a lot of work.

I'm open to reworking this 5 times if need be :)

>
> But before we get going, how many sub-devices does this have?

This is a custom piece of h/w which exposes two anybus-S slots, plus a
power readout in sysfs, I wasn't quite sure if mfd is the right
abstraction for this.

[PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Sven Van Asbroeck]

This patch adds devicetree binding documentation for the
Arcx anybus bridge.

Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
---
 .../bindings/mfd/arcx,anybus-bridge.txt       | 37 +++++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.txt   |  1 +
 2 files changed, 38 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt

diff --git a/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
new file mode 100644
index 000000000000..3c0399c4ed45
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
@@ -0,0 +1,37 @@
+* Arcx anybus bridge
+
+This chip communicates with the SoC over the WEIM bus. It is
+expected that its Device Tree node is specified as the child of a node
+corresponding to the WEIM bus used for communication.
+
+Required properties:
+
+  - compatible : The following chip-specific string:
+        "arcx,anybus-bridge"
+
+  - reg :
+	weim memory area where the cpld registers are located,	followed by:
+	weim memory area of the first  anybus-s slot,		followed by:
+	weim memory area of the second anybus-s slot.
+
+  - enable-gpios : the gpio connected to the bridge's 'enable gpio'.
+
+  - pwms : the pwm connected to the bridge's 'pwm input'.
+
+  - irq-gpios : the gpios connected to the bridge's interrupt lines.
+	note that there is no need to provide the 'interrupts' property here.
+
+Example of usage:
+
+&weim {
+	bridge@0,0 {
+		compatible = "arcx,anybus-bridge";
+		reg = <0 0 0x100>, <0 0x400000 0x800>, <1 0x400000 0x800>;
+		fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
+				0x00000000 0xa0000240 0x00000000>;
+		enable-gpios = <&gpio5 2 GPIO_ACTIVE_HIGH>;
+		pwms = <&pwm3 0 571>;
+		irq-gpios = <&gpio1 1 GPIO_ACTIVE_HIGH>,
+					<&gpio1 5 GPIO_ACTIVE_HIGH>;
+	};
+};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 2c3fc512e746..1bf07b20a8af 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -35,6 +35,7 @@ aptina	Aptina Imaging
 arasan	Arasan Chip Systems
 archermind ArcherMind Technology (Nanjing) Co., Ltd.
 arctic	Arctic Sand
+arcx	Arcx/Archronix Inc.
 aries	Aries Embedded GmbH
 arm	ARM Ltd.
 armadeus	ARMadeus Systems SARL
-- 
2.17.1

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Rob Herring]

On Wed, Oct 24, 2018 at 10:24:54AM -0400, Sven Van Asbroeck wrote:
> This patch adds devicetree binding documentation for the
> Arcx anybus bridge.
> 
> Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
> ---
>  .../bindings/mfd/arcx,anybus-bridge.txt       | 37 +++++++++++++++++++
>  .../devicetree/bindings/vendor-prefixes.txt   |  1 +
>  2 files changed, 38 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> 
> diff --git a/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> new file mode 100644
> index 000000000000..3c0399c4ed45
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> @@ -0,0 +1,37 @@
> +* Arcx anybus bridge
> +
> +This chip communicates with the SoC over the WEIM bus. It is
> +expected that its Device Tree node is specified as the child of a node
> +corresponding to the WEIM bus used for communication.

By WEIM you are referring to i.MX external parallel bus? Presumably this 
can work on any parallel bus, not just i.MX.

> +
> +Required properties:
> +
> +  - compatible : The following chip-specific string:
> +        "arcx,anybus-bridge"

No version or part number?

> +
> +  - reg :
> +	weim memory area where the cpld registers are located,	followed by:
> +	weim memory area of the first  anybus-s slot,		followed by:
> +	weim memory area of the second anybus-s slot.
> +
> +  - enable-gpios : the gpio connected to the bridge's 'enable gpio'.
> +
> +  - pwms : the pwm connected to the bridge's 'pwm input'.
> +
> +  - irq-gpios : the gpios connected to the bridge's interrupt lines.
> +	note that there is no need to provide the 'interrupts' property here.

Why not? This should not be base on what the OS currently happens to 
support.

What are the functions of each line? The order must be defined.

> +
> +Example of usage:
> +
> +&weim {
> +	bridge@0,0 {
> +		compatible = "arcx,anybus-bridge";
> +		reg = <0 0 0x100>, <0 0x400000 0x800>, <1 0x400000 0x800>;
> +		fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
> +				0x00000000 0xa0000240 0x00000000>;
> +		enable-gpios = <&gpio5 2 GPIO_ACTIVE_HIGH>;
> +		pwms = <&pwm3 0 571>;
> +		irq-gpios = <&gpio1 1 GPIO_ACTIVE_HIGH>,
> +					<&gpio1 5 GPIO_ACTIVE_HIGH>;
> +	};
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index 2c3fc512e746..1bf07b20a8af 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -35,6 +35,7 @@ aptina	Aptina Imaging
>  arasan	Arasan Chip Systems
>  archermind ArcherMind Technology (Nanjing) Co., Ltd.
>  arctic	Arctic Sand
> +arcx	Arcx/Archronix Inc.
>  aries	Aries Embedded GmbH
>  arm	ARM Ltd.
>  armadeus	ARMadeus Systems SARL
> -- 
> 2.17.1
> 

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Lee Jones]

On Wed, 24 Oct 2018, Sven Van Asbroeck wrote:

> This patch adds devicetree binding documentation for the
> Arcx anybus bridge.
> 
> Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
> ---
>  .../bindings/mfd/arcx,anybus-bridge.txt       | 37 +++++++++++++++++++
>  .../devicetree/bindings/vendor-prefixes.txt   |  1 +
>  2 files changed, 38 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> 
> diff --git a/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> new file mode 100644
> index 000000000000..3c0399c4ed45
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
> @@ -0,0 +1,37 @@
> +* Arcx anybus bridge
> +
> +This chip communicates with the SoC over the WEIM bus. It is
> +expected that its Device Tree node is specified as the child of a node
> +corresponding to the WEIM bus used for communication.
> +
> +Required properties:
> +
> +  - compatible : The following chip-specific string:
> +        "arcx,anybus-bridge"
> +
> +  - reg :
> +	weim memory area where the cpld registers are located,	followed by:
> +	weim memory area of the first  anybus-s slot,		followed by:
> +	weim memory area of the second anybus-s slot.
> +
> +  - enable-gpios : the gpio connected to the bridge's 'enable gpio'.
> +
> +  - pwms : the pwm connected to the bridge's 'pwm input'.
> +
> +  - irq-gpios : the gpios connected to the bridge's interrupt lines.
> +	note that there is no need to provide the 'interrupts' property here.
> +
> +Example of usage:
> +
> +&weim {
> +	bridge@0,0 {

I haven't seen this syntax before.

It doesn't mean it's wrong, but will needs Rob et. al to cast an eye.

> +		compatible = "arcx,anybus-bridge";
> +		reg = <0 0 0x100>, <0 0x400000 0x800>, <1 0x400000 0x800>;
> +		fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
> +				0x00000000 0xa0000240 0x00000000>;

This needs to be documented.

> +		enable-gpios = <&gpio5 2 GPIO_ACTIVE_HIGH>;
> +		pwms = <&pwm3 0 571>;
> +		irq-gpios = <&gpio1 1 GPIO_ACTIVE_HIGH>,
> +					<&gpio1 5 GPIO_ACTIVE_HIGH>;

Tabbing.

> +	};
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index 2c3fc512e746..1bf07b20a8af 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -35,6 +35,7 @@ aptina	Aptina Imaging
>  arasan	Arasan Chip Systems
>  archermind ArcherMind Technology (Nanjing) Co., Ltd.
>  arctic	Arctic Sand
> +arcx	Arcx/Archronix Inc.
>  aries	Aries Embedded GmbH
>  arm	ARM Ltd.
>  armadeus	ARMadeus Systems SARL

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Linus Walleij]

Hi Sven,

thanks for your patch!

On Wed, Oct 24, 2018 at 4:25 PM Sven Van Asbroeck <svendev@arcx.com> wrote:

> +  - pwms : the pwm connected to the bridge's 'pwm input'.

That is really unintuitive and needs a detailed explanation. What
is a bridge doing with a PWM? Is it 100% certain this is a PWM,
it's not just a .... clock? A pwm is a pule WIDTH modulator and
I can't for my life understand why a bus bridge needs a signal
with variable pulse width, but surprise me! :D

> +               fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
> +                               0x00000000 0xa0000240 0x00000000>;

Is it just a copy/paste from
Documentation/devicetree/bindings/bus/imx-weim.txt
leftover?

It was mentioned as undocumented but it is also pretty terse
with these opaque hex numbers. I would never let the
Freescale binding pass if I was reviewing it.

Look at my bindings for Qualcomm EBI in
Documentation/devicetree/bindings/bus/qcom,ebi2.txt
for example.

But maybe it's not even supposed to be there.

Yours,
Linus Walleij

[PATCH anybus v1 3/4] bus: support HMS Anybus-S bus.

[Sven Van Asbroeck]

The Anybus-S/Anybus-M is a series of interchangeable fieldbus communication
modules featuring on board memory and processing power. All software and
hardware functionality required to communicate on the fieldbus is
incorporated in the module itself, allowing the application to focus on
other tasks.

Typical applications are frequency inverters, HMI and visualization
devices, instruments, scales, robotics, PLC’s and intelligent measuring
devices.

Official documentation:
https://www.anybus.com/docs/librariesprovider7/default-document-library/
manuals-design-guides/hms-hmsi-27-275.pdf

This driver implementation is designed to be almost completely independent
from the way the Anybus-S hardware is accessed by the SoC. All it needs is:

- a regmap which accesses the underlying Anybus-S dpram by whatever means;
- an interrupt line, ultimately connected to the Anybus-S card;
- a reset function.

Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
---
 drivers/bus/Kconfig            |   11 +
 drivers/bus/Makefile           |    1 +
 drivers/bus/anybuss-host.c     | 1301 ++++++++++++++++++++++++++++++++
 include/linux/anybuss-client.h |  100 +++
 4 files changed, 1413 insertions(+)
 create mode 100644 drivers/bus/anybuss-host.c
 create mode 100644 include/linux/anybuss-client.h

diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 1851112ccc29..68869648b9ab 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -45,6 +45,17 @@ config IMX_WEIM
 	  The WEIM(Wireless External Interface Module) works like a bus.
 	  You can attach many different devices on it, such as NOR, onenand.
 
+config HMS_ANYBUSS_HOST
+	tristate "HMS Anybus-S Host/Bus Driver"
+	select REGMAP
+	depends on OF
+	default n
+	help
+	  Driver for the HMS Industrial Networks Anybus-S bus.
+	  You can attach Anybus-S compatible cards to it, which
+	  typically provide fieldbus and industrial ethernet
+	  functionality.
+
 config MIPS_CDMM
 	bool "MIPS Common Device Memory Map (CDMM) Driver"
 	depends on CPU_MIPSR2
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index ca300b1914ce..f67c6468126b 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_BRCMSTB_GISB_ARB)	+= brcmstb_gisb.o
 obj-$(CONFIG_FSL_MC_BUS)	+= fsl-mc/
 
 obj-$(CONFIG_IMX_WEIM)		+= imx-weim.o
+obj-$(CONFIG_HMS_ANYBUSS_HOST)	+= anybuss-host.o
 obj-$(CONFIG_MIPS_CDMM)		+= mips_cdmm.o
 obj-$(CONFIG_MVEBU_MBUS) 	+= mvebu-mbus.o
 
diff --git a/drivers/bus/anybuss-host.c b/drivers/bus/anybuss-host.c
new file mode 100644
index 000000000000..41d62937a5eb
--- /dev/null
+++ b/drivers/bus/anybuss-host.c
@@ -0,0 +1,1301 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HMS Anybus-S Host Driver
+ *
+ * Copyright (C) 2018 Arcx Inc
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/atomic.h>
+#include <linux/kthread.h>
+#include <linux/kfifo.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+
+#include <linux/anybuss-host.h>
+#include <linux/anybuss-client.h>
+
+#define DPRAM_SIZE		0x800
+#define MAX_MBOX_MSG_SZ		0x0FF
+#define TIMEOUT			(HZ*2)
+#define MAX_DATA_AREA_SZ	0x200
+#define MAX_FBCTRL_AREA_SZ	0x1BE
+
+#define REG_BOOTLOADER_V	0x7C0
+#define REG_API_V		0x7C2
+#define REG_FIELDBUS_V		0x7C4
+#define REG_SERIAL_NO		0x7C6
+#define REG_FIELDBUS_TYPE	0x7CC
+#define REG_MODULE_SW_V		0x7CE
+#define REG_IND_AB		0x7FF
+#define REG_IND_AP		0x7FE
+#define REG_EVENT_CAUSE		0x7ED
+#define MBOX_IN_AREA		0x400
+#define MBOX_OUT_AREA		0x520
+#define DATA_IN_AREA		0x000
+#define DATA_OUT_AREA		0x200
+#define FBCTRL_AREA		0x640
+
+#define EVENT_CAUSE_DC          0x01
+#define EVENT_CAUSE_FBOF        0x02
+#define EVENT_CAUSE_FBON        0x04
+
+#define IND_AB_UPDATED		0x08
+#define IND_AX_MIN		0x80
+#define IND_AX_MOUT		0x40
+#define IND_AX_IN		0x04
+#define IND_AX_OUT		0x02
+#define IND_AX_FBCTRL		0x01
+#define IND_AP_LOCK		0x08
+#define IND_AP_ACTION		0x10
+#define IND_AX_EVNT		0x20
+#define IND_AP_ABITS		(IND_AX_IN | IND_AX_OUT | \
+					IND_AX_FBCTRL | \
+					IND_AP_ACTION | IND_AP_LOCK)
+
+#define INFO_TYPE_FB		0x0002
+#define INFO_TYPE_APP		0x0001
+#define INFO_COMMAND		0x4000
+
+#define OP_MODE_FBFC		0x0002
+#define OP_MODE_FBS		0x0004
+#define OP_MODE_CD		0x0200
+
+#define CMD_START_INIT		0x0001
+#define CMD_ANYBUS_INIT		0x0002
+#define CMD_END_INIT		0x0003
+
+/* ------------- ref counted tasks ------------- */
+
+struct ab_task;
+typedef int (*ab_task_fn_t)(struct anybuss_host *cd,
+					struct ab_task *t);
+typedef void (*ab_done_fn_t)(struct anybuss_host *cd);
+
+struct area_priv {
+	bool is_write;
+	u16 flags;
+	u16 addr;
+	size_t count;
+	u8 buf[MAX_DATA_AREA_SZ];
+};
+
+struct anybus_mbox_hdr {
+	u16 id;
+	u16 info;
+	u16 cmd_num;
+	u16 data_size;
+	u16 frame_count;
+	u16 frame_num;
+	u16 offset_high;
+	u16 offset_low;
+	u16 extended[8];
+} __packed;
+
+struct mbox_priv {
+	struct anybus_mbox_hdr hdr;
+	size_t msg_out_sz;
+	size_t msg_in_sz;
+	u8 msg[MAX_MBOX_MSG_SZ];
+};
+
+struct ab_task {
+	struct kmem_cache	*cache;
+	atomic_t		refs;
+	ab_task_fn_t		task_fn;
+	ab_done_fn_t		done_fn;
+	int			result;
+	struct completion	done;
+	unsigned long		start_jiffies;
+	union {
+		struct area_priv area_pd;
+		struct mbox_priv mbox_pd;
+	};
+};
+
+static struct ab_task *ab_task_create_get(struct kmem_cache *cache,
+			ab_task_fn_t task_fn)
+{
+	struct ab_task *t;
+
+	t = kmem_cache_alloc(cache, GFP_KERNEL);
+	if (!t)
+		return NULL;
+	t->cache = cache;
+	atomic_set(&t->refs, 1);
+	t->task_fn = task_fn;
+	t->done_fn = NULL;
+	t->result = 0;
+	init_completion(&t->done);
+	return t;
+}
+
+static void ab_task_put(struct ab_task *t)
+{
+	struct kmem_cache *cache = t->cache;
+
+	if (atomic_dec_and_test(&t->refs))
+		kmem_cache_free(cache, t);
+}
+
+static struct ab_task *__ab_task_get(struct ab_task *t)
+{
+	atomic_inc(&t->refs);
+	return t;
+}
+
+static void
+__ab_task_finish(struct anybuss_host *cd, struct ab_task *t)
+{
+	if (t->done_fn)
+		t->done_fn(cd);
+	complete(&t->done);
+}
+
+static void
+ab_task_dequeue_finish_put(struct anybuss_host *cd, struct kfifo *q)
+{
+	int ret;
+	struct ab_task *t;
+
+	ret = kfifo_out(q, &t, sizeof(t));
+	WARN_ON(!ret);
+	__ab_task_finish(cd, t);
+	ab_task_put(t);
+}
+
+static int
+ab_task_enqueue(wait_queue_head_t *wq, struct kfifo *q,
+			struct ab_task *t, spinlock_t *slock)
+{
+	int ret;
+
+	t->start_jiffies = jiffies;
+	ret = kfifo_in_spinlocked(q, &t, sizeof(t), slock);
+	if (!ret)
+		return -ENOMEM;
+	__ab_task_get(t);
+	wake_up(wq);
+	return 0;
+}
+
+static int
+ab_task_enqueue_wait(wait_queue_head_t *wq, struct kfifo *q,
+			struct ab_task *t, spinlock_t *slock)
+{
+	int ret;
+
+	ret = ab_task_enqueue(wq, q, t, slock);
+	if (ret)
+		return ret;
+	ret = wait_for_completion_interruptible(&t->done);
+	if (ret)
+		return ret;
+	return t->result;
+}
+
+/* ------------------------ anybus hardware ------------------------ */
+
+struct anybuss_host {
+	struct device *dev;
+	struct device *parent;
+	struct anybuss_client *client;
+	anybuss_reset_t reset;
+	struct regmap *regmap;
+	int irq;
+	struct task_struct *qthread;
+	wait_queue_head_t wq;
+	struct completion card_boot;
+	atomic_t ind_ab;
+	spinlock_t qlock;
+	struct kmem_cache *qcache;
+	struct kfifo qs[3];
+	struct kfifo *powerq;
+	struct kfifo *mboxq;
+	struct kfifo *areaq;
+	bool power_on;
+	bool softint_pending;
+	atomic_t dc_event;
+	wait_queue_head_t dc_wq;
+	atomic_t fieldbus_online;
+	struct kernfs_node *fieldbus_online_sd;
+};
+
+static int test_dpram(struct regmap *regmap)
+{
+	int i;
+	unsigned int val;
+
+	for (i = 0; i < DPRAM_SIZE; i++)
+		regmap_write(regmap, i, (u8)i);
+	for (i = 0; i < DPRAM_SIZE; i++) {
+		regmap_read(regmap, i, &val);
+		if ((u8)val != (u8)i)
+			return -EIO;
+	}
+	return 0;
+}
+
+static void ab_reset(struct anybuss_host *cd, bool reset)
+{
+	cd->reset(cd->parent, reset);
+}
+
+static int read_ind_ab(struct regmap *regmap)
+{
+	unsigned long timeout = jiffies + HZ/2;
+	unsigned int a, b;
+
+	while (time_before_eq(jiffies, timeout)) {
+		regmap_read(regmap, REG_IND_AB, &a);
+		regmap_read(regmap, REG_IND_AB, &b);
+		if (likely(a == b))
+			return (int)a;
+		cpu_relax();
+	}
+	WARN(1, "IND_AB register not stable");
+	return -ETIMEDOUT;
+}
+
+static int write_ind_ap(struct regmap *regmap, unsigned int ind_ap)
+{
+	unsigned long timeout = jiffies + HZ/2;
+	unsigned int v;
+
+	while (time_before_eq(jiffies, timeout)) {
+		regmap_write(regmap, REG_IND_AP, ind_ap);
+		regmap_read(regmap, REG_IND_AP, &v);
+		if (likely(ind_ap == v))
+			return 0;
+		cpu_relax();
+	}
+	WARN(1, "IND_AP register not stable");
+	return -ETIMEDOUT;
+}
+
+static irqreturn_t irq_handler(int irq, void *data)
+{
+	struct anybuss_host *cd = data;
+	int ind_ab;
+
+	/* reading the anybus indicator register acks the interrupt */
+	ind_ab = read_ind_ab(cd->regmap);
+	if (ind_ab < 0)
+		return IRQ_NONE;
+	atomic_set(&cd->ind_ab, ind_ab);
+	complete(&cd->card_boot);
+	wake_up(&cd->wq);
+	return IRQ_HANDLED;
+}
+
+/* ------------------------ power on/off tasks --------------------- */
+
+static int task_fn_power_off(struct anybuss_host *cd,
+				struct ab_task *t)
+{
+	if (!cd->power_on)
+		return 0;
+	disable_irq(cd->irq);
+	ab_reset(cd, true);
+	atomic_set(&cd->ind_ab, IND_AB_UPDATED);
+	atomic_set(&cd->fieldbus_online, 0);
+	sysfs_notify_dirent(cd->fieldbus_online_sd);
+	cd->power_on = false;
+	return 0;
+}
+
+static int task_fn_power_on_2(struct anybuss_host *cd,
+				struct ab_task *t)
+{
+	if (completion_done(&cd->card_boot)) {
+		cd->power_on = true;
+		return 0;
+	}
+	if (time_after(jiffies, t->start_jiffies + TIMEOUT)) {
+		disable_irq(cd->irq);
+		ab_reset(cd, true);
+		dev_err(cd->dev, "power on timed out");
+		return -ETIMEDOUT;
+	}
+	return -EINPROGRESS;
+}
+
+static int task_fn_power_on(struct anybuss_host *cd,
+				struct ab_task *t)
+{
+	unsigned int dummy;
+
+	if (cd->power_on)
+		return 0;
+	/* anybus docs: prevent false 'init done' interrupt by
+	 * doing a dummy read of IND_AB register while in reset.
+	 */
+	regmap_read(cd->regmap, REG_IND_AB, &dummy);
+	reinit_completion(&cd->card_boot);
+	enable_irq(cd->irq);
+	ab_reset(cd, false);
+	t->task_fn = task_fn_power_on_2;
+	return -EINPROGRESS;
+}
+
+int anybuss_set_power(struct anybuss_client *client, bool power_on)
+{
+	struct anybuss_host *cd = client->host;
+	struct ab_task *t;
+	int err;
+
+	t = ab_task_create_get(cd->qcache, power_on ?
+				task_fn_power_on : task_fn_power_off);
+	if (!t)
+		return -ENOMEM;
+	err = ab_task_enqueue_wait(&cd->wq, cd->powerq, t, &cd->qlock);
+	ab_task_put(t);
+	return err;
+}
+EXPORT_SYMBOL_GPL(anybuss_set_power);
+
+/* ---------------------------- area tasks ------------------------ */
+
+static int task_fn_area_3(struct anybuss_host *cd, struct ab_task *t)
+{
+	struct area_priv *pd = &t->area_pd;
+
+	if (!cd->power_on)
+		return -EIO;
+	if (atomic_read(&cd->ind_ab) & pd->flags) {
+		/* area not released yet */
+		if (time_after(jiffies, t->start_jiffies + TIMEOUT))
+			return -ETIMEDOUT;
+		return -EINPROGRESS;
+	}
+	return 0;
+}
+
+static int task_fn_area_2(struct anybuss_host *cd, struct ab_task *t)
+{
+	struct area_priv *pd = &t->area_pd;
+	unsigned int ind_ap;
+	int ret;
+
+	if (!cd->power_on)
+		return -EIO;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	if (!(atomic_read(&cd->ind_ab) & pd->flags)) {
+		/* we don't own the area yet */
+		if (time_after(jiffies, t->start_jiffies + TIMEOUT)) {
+			dev_warn(cd->dev, "timeout waiting for area");
+			dump_stack();
+			return -ETIMEDOUT;
+		}
+		return -EINPROGRESS;
+	}
+	/* we own the area, do what we're here to do */
+	if (pd->is_write)
+		regmap_bulk_write(cd->regmap, pd->addr, pd->buf,
+							pd->count);
+	else
+		regmap_bulk_read(cd->regmap, pd->addr, pd->buf,
+							pd->count);
+	/* ask to release the area, must use unlocked release */
+	ind_ap &= ~IND_AP_ABITS;
+	ind_ap |= pd->flags;
+	ret = write_ind_ap(cd->regmap, ind_ap);
+	if (ret)
+		return ret;
+	t->task_fn = task_fn_area_3;
+	return -EINPROGRESS;
+}
+
+static int task_fn_area(struct anybuss_host *cd, struct ab_task *t)
+{
+	struct area_priv *pd = &t->area_pd;
+	unsigned int ind_ap;
+	int ret;
+
+	if (!cd->power_on)
+		return -EIO;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	/* ask to take the area */
+	ind_ap &= ~IND_AP_ABITS;
+	ind_ap |= pd->flags | IND_AP_ACTION | IND_AP_LOCK;
+	ret = write_ind_ap(cd->regmap, ind_ap);
+	if (ret)
+		return ret;
+	t->task_fn = task_fn_area_2;
+	return -EINPROGRESS;
+}
+
+static struct ab_task *
+create_area_reader(struct kmem_cache *qcache, u16 flags, u16 addr,
+				size_t count)
+{
+	struct ab_task *t;
+	struct area_priv *ap;
+
+	t = ab_task_create_get(qcache, task_fn_area);
+	if (!t)
+		return NULL;
+	ap = &t->area_pd;
+	ap->flags = flags;
+	ap->addr = addr;
+	ap->is_write = false;
+	ap->count = count;
+	return t;
+}
+
+static struct ab_task *
+create_area_writer(struct kmem_cache *qcache, u16 flags, u16 addr,
+				const void *buf, size_t count)
+{
+	struct ab_task *t;
+	struct area_priv *ap;
+
+	t = ab_task_create_get(qcache, task_fn_area);
+	if (!t)
+		return NULL;
+	ap = &t->area_pd;
+	ap->flags = flags;
+	ap->addr = addr;
+	ap->is_write = true;
+	ap->count = count;
+	memcpy(ap->buf, buf, count);
+	return t;
+}
+
+static struct ab_task *
+create_area_user_writer(struct kmem_cache *qcache, u16 flags, u16 addr,
+				const void __user *buf, size_t count)
+{
+	struct ab_task *t;
+	struct area_priv *ap;
+
+	t = ab_task_create_get(qcache, task_fn_area);
+	if (!t)
+		return ERR_PTR(-ENOMEM);
+	ap = &t->area_pd;
+	ap->flags = flags;
+	ap->addr = addr;
+	ap->is_write = true;
+	ap->count = count;
+	if (copy_from_user(ap->buf, buf, count)) {
+		ab_task_put(t);
+		return ERR_PTR(-EFAULT);
+	}
+	return t;
+}
+
+static bool area_range_ok(u16 addr, size_t count, u16 area_start,
+							size_t area_sz)
+{
+	u16 area_end_ex = area_start + area_sz;
+	u16 addr_end_ex;
+
+	if (addr < area_start)
+		return false;
+	if (addr >= area_end_ex)
+		return false;
+	addr_end_ex = addr + count;
+	if (addr_end_ex > area_end_ex)
+		return false;
+	return true;
+}
+
+/* -------------------------- mailbox tasks ----------------------- */
+
+struct msgAnybusInit {
+	u16 input_io_len;
+	u16 input_dpram_len;
+	u16 input_total_len;
+	u16 output_io_len;
+	u16 output_dpram_len;
+	u16 output_total_len;
+	u16 op_mode;
+	u16 notif_config;
+	u16 wd_val;
+} __packed;
+
+static int task_fn_mbox_2(struct anybuss_host *cd, struct ab_task *t)
+{
+	struct mbox_priv *pd = &t->mbox_pd;
+	unsigned int ind_ap;
+
+	if (!cd->power_on)
+		return -EIO;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	if (((atomic_read(&cd->ind_ab) ^ ind_ap) & IND_AX_MOUT) == 0) {
+		/* output message not here */
+		if (time_after(jiffies, t->start_jiffies + TIMEOUT))
+			return -ETIMEDOUT;
+		return -EINPROGRESS;
+	}
+	/* grab the returned header and msg */
+	regmap_bulk_read(cd->regmap, MBOX_OUT_AREA, &pd->hdr,
+		sizeof(pd->hdr));
+	regmap_bulk_read(cd->regmap, MBOX_OUT_AREA + sizeof(pd->hdr),
+		pd->msg, pd->msg_in_sz);
+	/* tell anybus we've consumed the message */
+	ind_ap ^= IND_AX_MOUT;
+	return write_ind_ap(cd->regmap, ind_ap);
+}
+
+static int task_fn_mbox(struct anybuss_host *cd, struct ab_task *t)
+{
+	struct mbox_priv *pd = &t->mbox_pd;
+	unsigned int ind_ap;
+	int ret;
+
+	if (!cd->power_on)
+		return -EIO;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	if ((atomic_read(&cd->ind_ab) ^ ind_ap) & IND_AX_MIN) {
+		/* mbox input area busy */
+		if (time_after(jiffies, t->start_jiffies + TIMEOUT))
+			return -ETIMEDOUT;
+		return -EINPROGRESS;
+	}
+	/* write the header and msg to input area */
+	regmap_bulk_write(cd->regmap, MBOX_IN_AREA, &pd->hdr,
+					sizeof(pd->hdr));
+	regmap_bulk_write(cd->regmap, MBOX_IN_AREA + sizeof(pd->hdr),
+					pd->msg, pd->msg_out_sz);
+	/* tell anybus we gave it a message */
+	ind_ap ^= IND_AX_MIN;
+	ret = write_ind_ap(cd->regmap, ind_ap);
+	if (ret)
+		return ret;
+	t->start_jiffies = jiffies;
+	t->task_fn = task_fn_mbox_2;
+	return -EINPROGRESS;
+}
+
+static const char * const O_MSGS[] = {
+	"Incorrect length of input I/O",		/* bit 0 */
+	"Incorrect length of DPRAM input",		/* bit 1 */
+	"Incorrect length of total input",		/* bit 2 */
+	"(reserved)",					/* bit 3 */
+	"Incorrect length of output I/O",		/* bit 4 */
+	"Incorrect length of DPRAM output",		/* bit 5 */
+	"Incorrect length of total output",		/* bit 6 */
+	"(reserved)",					/* bit 7 */
+	"Incorrect config of Module Status reg",	/* bit 8 */
+	"Incorrect config of Event Notification reg",	/* bit 9 */
+	"Incorrect Watchdog Counter difference value",	/* bit 10 */
+};
+
+static void log_invalid_other(struct device *dev,
+				struct anybus_mbox_hdr *hdr)
+{
+	int i;
+	size_t ext_offs = sizeof(hdr->extended) - 1;
+	u16 code = be16_to_cpu(hdr->extended[ext_offs]);
+
+	dev_err(dev, "   Invalid other: [0x%02X]", code);
+	for (i = 0; code != 0; code >>= 1, i++)
+		if ((code & 1) && (i < ARRAY_SIZE(O_MSGS)))
+			dev_err(dev, "\t%s", O_MSGS[i]);
+}
+
+static const char * const EMSGS[] = {
+	"Invalid Message ID",
+	"Invalid Message Type",
+	"Invalid Command",
+	"Invalid Data Size",
+	"Message Header Malformed (offset 008h)",
+	"Message Header Malformed (offset 00Ah)",
+	"Message Header Malformed (offset 00Ch - 00Dh)",
+	"Invalid Address",
+	"Invalid Response",
+	"Flash Config Error",
+};
+
+static int mbox_cmd_err(struct device *dev, struct mbox_priv *mpriv)
+{
+	int i;
+	u8 ecode;
+	struct anybus_mbox_hdr *hdr = &mpriv->hdr;
+	u16 info = be16_to_cpu(hdr->info);
+	u8 *phdr = (u8 *)hdr;
+	u8 *pmsg = mpriv->msg;
+
+	if (!(info & 0x8000))
+		return 0;
+	ecode = (info >> 8) & 0x0F;
+	dev_err(dev, "mailbox command failed:");
+	if (ecode == 0x0F)
+		log_invalid_other(dev, hdr);
+	else if (ecode < ARRAY_SIZE(EMSGS))
+		dev_err(dev, "   Error code: %s (0x%02X)",
+			EMSGS[ecode], ecode);
+	else
+		dev_err(dev, "   Error code: 0x%02X\n", ecode);
+	dev_err(dev, "Failed command:");
+	dev_err(dev, "Message Header:");
+	for (i = 0; i < sizeof(mpriv->hdr); i += 2)
+		dev_err(dev, "%02X%02X", phdr[i], phdr[i+1]);
+	dev_err(dev, "Message Data:");
+	for (i = 0; i < mpriv->msg_in_sz; i += 2)
+		dev_err(dev, "%02X%02X", pmsg[i], pmsg[i+1]);
+	dev_err(dev, "Stack dump:");
+	dump_stack();
+	return -EIO;
+}
+
+static int _anybus_mbox_cmd(struct anybuss_host *cd,
+				u16 cmd_num, bool is_fb_cmd,
+				const void *msg_out, size_t msg_out_sz,
+				void *msg_in, size_t msg_in_sz,
+				const void *ext, size_t ext_sz)
+{
+	struct ab_task *t;
+	struct mbox_priv *pd;
+	struct anybus_mbox_hdr *h;
+	size_t msg_sz = max(msg_in_sz, msg_out_sz);
+	u16 info;
+	int err;
+
+	if (msg_sz > MAX_MBOX_MSG_SZ)
+		return -EINVAL;
+	if (ext && (ext_sz > sizeof(h->extended)))
+		return -EINVAL;
+	t = ab_task_create_get(cd->qcache, task_fn_mbox);
+	if (!t)
+		return -ENOMEM;
+	pd = &t->mbox_pd;
+	h = &pd->hdr;
+	info = is_fb_cmd ? INFO_TYPE_FB : INFO_TYPE_APP;
+	/* prevent uninitialized memory in the header from being sent
+	 * across the anybus
+	 */
+	memset(h, 0, sizeof(*h));
+	h->info = cpu_to_be16(info | INFO_COMMAND);
+	h->cmd_num = cpu_to_be16(cmd_num);
+	h->data_size = cpu_to_be16(msg_out_sz);
+	h->frame_count = cpu_to_be16(1);
+	h->frame_num = cpu_to_be16(1);
+	h->offset_high = cpu_to_be16(0);
+	h->offset_low = cpu_to_be16(0);
+	if (ext)
+		memcpy(h->extended, ext, ext_sz);
+	memcpy(pd->msg, msg_out, msg_out_sz);
+	pd->msg_out_sz = msg_out_sz;
+	pd->msg_in_sz = msg_in_sz;
+	err = ab_task_enqueue_wait(&cd->wq, cd->mboxq, t, &cd->qlock);
+	if (err)
+		goto out;
+	/* mailbox mechanism worked ok, but maybe the mbox response
+	 * contains an error ?
+	 */
+	err = mbox_cmd_err(cd->dev, pd);
+	if (err)
+		goto out;
+	memcpy(msg_in, pd->msg, msg_in_sz);
+out:
+	ab_task_put(t);
+	return err;
+}
+
+/* ------------------------ anybus queues ------------------------ */
+
+static void process_q(struct anybuss_host *cd, struct kfifo *q)
+{
+	struct ab_task *t;
+	int ret;
+
+	ret = kfifo_out_peek(q, &t, sizeof(t));
+	if (!ret)
+		return;
+	t->result = t->task_fn(cd, t);
+	if (t->result != -EINPROGRESS)
+		ab_task_dequeue_finish_put(cd, q);
+}
+
+static bool qs_have_work(struct kfifo *qs, size_t num)
+{
+	size_t i;
+	struct ab_task *t;
+	int ret;
+
+	for (i = 0; i < num; i++, qs++) {
+		ret = kfifo_out_peek(qs, &t, sizeof(t));
+		if (ret && (t->result != -EINPROGRESS))
+			return true;
+	}
+	return false;
+}
+
+static void process_qs(struct anybuss_host *cd)
+{
+	size_t i;
+	struct kfifo *qs = cd->qs;
+	size_t nqs = ARRAY_SIZE(cd->qs);
+
+	for (i = 0; i < nqs; i++, qs++)
+		process_q(cd, qs);
+}
+
+static void softint_ack(struct anybuss_host *cd)
+{
+	unsigned int ind_ap;
+
+	cd->softint_pending = false;
+	if (!cd->power_on)
+		return;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	ind_ap &= ~IND_AX_EVNT;
+	ind_ap |= atomic_read(&cd->ind_ab) & IND_AX_EVNT;
+	write_ind_ap(cd->regmap, ind_ap);
+}
+
+static void process_softint(struct anybuss_host *cd)
+{
+	static const u8 zero;
+	int ret;
+	unsigned int ind_ap, ev;
+	struct ab_task *t;
+
+	if (!cd->power_on)
+		return;
+	if (cd->softint_pending)
+		return;
+	regmap_read(cd->regmap, REG_IND_AP, &ind_ap);
+	if (!((atomic_read(&cd->ind_ab) ^ ind_ap) & IND_AX_EVNT))
+		return;
+	/* process software interrupt */
+	regmap_read(cd->regmap, REG_EVENT_CAUSE, &ev);
+	if (ev & EVENT_CAUSE_FBON) {
+		atomic_set(&cd->fieldbus_online, 1);
+		sysfs_notify_dirent(cd->fieldbus_online_sd);
+		dev_dbg(cd->dev, "Fieldbus ON");
+	}
+	if (ev & EVENT_CAUSE_FBOF) {
+		atomic_set(&cd->fieldbus_online, 0);
+		sysfs_notify_dirent(cd->fieldbus_online_sd);
+		dev_dbg(cd->dev, "Fieldbus OFF");
+	}
+	if (ev & EVENT_CAUSE_DC) {
+		atomic_inc(&cd->dc_event);
+		wake_up_all(&cd->dc_wq);
+		dev_dbg(cd->dev, "Fieldbus data changed");
+	}
+	/* reset the event cause bits.
+	 * this must be done while owning the fbctrl area, so we'll
+	 * enqueue a task to do that.
+	 */
+	t = create_area_writer(cd->qcache, IND_AX_FBCTRL,
+		REG_EVENT_CAUSE, &zero, sizeof(zero));
+	if (!t) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	t->done_fn = softint_ack;
+	ret = ab_task_enqueue(&cd->wq, cd->areaq, t, &cd->qlock);
+	ab_task_put(t);
+	cd->softint_pending = true;
+out:
+	WARN_ON(ret);
+	if (ret)
+		softint_ack(cd);
+}
+
+static int qthread_fn(void *data)
+{
+	struct anybuss_host *cd = data;
+	struct kfifo *qs = cd->qs;
+	size_t nqs = ARRAY_SIZE(cd->qs);
+	unsigned int ind_ab;
+
+	while (!kthread_should_stop()) {
+		ind_ab = atomic_read(&cd->ind_ab);
+		process_qs(cd);
+		process_softint(cd);
+		wait_event_timeout(cd->wq,
+			(atomic_read(&cd->ind_ab) != ind_ab) ||
+				qs_have_work(qs, nqs) ||
+				kthread_should_stop(),
+			HZ);
+	}
+
+	return 0;
+}
+
+/* ------------------------ anybus exports ------------------------ */
+
+int anybuss_start_init(struct anybuss_client *client,
+			const struct anybuss_memcfg *cfg)
+{
+	int ret;
+	u16 op_mode;
+	struct anybuss_host *cd = client->host;
+	struct msgAnybusInit msg = {
+		.input_io_len = cpu_to_be16(cfg->input_io),
+		.input_dpram_len = cpu_to_be16(cfg->input_dpram),
+		.input_total_len = cpu_to_be16(cfg->input_total),
+		.output_io_len = cpu_to_be16(cfg->output_io),
+		.output_dpram_len = cpu_to_be16(cfg->output_dpram),
+		.output_total_len = cpu_to_be16(cfg->output_total),
+		.notif_config = cpu_to_be16(0x000F),
+		.wd_val = cpu_to_be16(0),
+	};
+
+	switch (cfg->offl_mode) {
+	case AB_OFFL_MODE_CLEAR:
+		op_mode = 0;
+		break;
+	case AB_OFFL_MODE_FREEZE:
+		op_mode = OP_MODE_FBFC;
+		break;
+	case AB_OFFL_MODE_SET:
+		op_mode = OP_MODE_FBS;
+		break;
+	default:
+		return -EINVAL;
+	}
+	msg.op_mode = cpu_to_be16(op_mode | OP_MODE_CD);
+	ret = _anybus_mbox_cmd(cd, CMD_START_INIT, false, NULL, 0,
+						NULL, 0, NULL, 0);
+	if (ret)
+		return ret;
+	return _anybus_mbox_cmd(cd, CMD_ANYBUS_INIT, false,
+			&msg, sizeof(msg), NULL, 0, NULL, 0);
+}
+EXPORT_SYMBOL_GPL(anybuss_start_init);
+
+int anybuss_finish_init(struct anybuss_client *client)
+{
+	struct anybuss_host *cd = client->host;
+
+	return _anybus_mbox_cmd(cd, CMD_END_INIT, false, NULL, 0,
+					NULL, 0, NULL, 0);
+}
+EXPORT_SYMBOL_GPL(anybuss_finish_init);
+
+int anybuss_read_fbctrl(struct anybuss_client *client, u16 addr,
+				void *buf, size_t count)
+{
+	struct anybuss_host *cd = client->host;
+	struct ab_task *t;
+	int ret;
+
+	if (count == 0)
+		return 0;
+	if (!area_range_ok(addr, count, FBCTRL_AREA,
+					MAX_FBCTRL_AREA_SZ))
+		return -EFAULT;
+	t = create_area_reader(cd->qcache, IND_AX_FBCTRL, addr, count);
+	if (!t)
+		return -ENOMEM;
+	ret = ab_task_enqueue_wait(&cd->wq, cd->areaq, t, &cd->qlock);
+	if (ret)
+		goto out;
+	memcpy(buf, t->area_pd.buf, count);
+out:
+	ab_task_put(t);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(anybuss_read_fbctrl);
+
+int anybuss_write_input(struct anybuss_client *client,
+				const char __user *buf, size_t size,
+				loff_t *offset)
+{
+	ssize_t len = min_t(loff_t, MAX_DATA_AREA_SZ - *offset, size);
+	struct anybuss_host *cd = client->host;
+	struct ab_task *t;
+	int ret;
+
+	if (len <= 0)
+		return 0;
+	t = create_area_user_writer(cd->qcache, IND_AX_IN,
+		DATA_IN_AREA + *offset, buf, len);
+	if (IS_ERR(t))
+		return PTR_ERR(t);
+	ret = ab_task_enqueue_wait(&cd->wq, cd->areaq, t, &cd->qlock);
+	ab_task_put(t);
+	if (ret)
+		return ret;
+	/* success */
+	*offset += len;
+	return len;
+}
+EXPORT_SYMBOL_GPL(anybuss_write_input);
+
+int anybuss_read_output(struct anybuss_client *client, int *dc_event,
+				char __user *buf, size_t size,
+				loff_t *offset)
+{
+	ssize_t len = min_t(loff_t, MAX_DATA_AREA_SZ - *offset, size);
+	struct anybuss_host *cd = client->host;
+	struct ab_task *t;
+	int ret;
+
+	if (len <= 0)
+		return 0;
+	t = create_area_reader(cd->qcache, IND_AX_OUT,
+		DATA_OUT_AREA + *offset, len);
+	if (!t)
+		return -ENOMEM;
+	*dc_event = atomic_read(&cd->dc_event);
+	ret = ab_task_enqueue_wait(&cd->wq, cd->areaq, t, &cd->qlock);
+	if (ret)
+		goto out;
+	if (copy_to_user(buf, t->area_pd.buf, len))
+		ret = -EFAULT;
+out:
+	ab_task_put(t);
+	if (ret)
+		return ret;
+	/* success */
+	*offset += len;
+	return len;
+}
+EXPORT_SYMBOL_GPL(anybuss_read_output);
+
+unsigned int anybuss_poll(struct anybuss_client *client, int dc_event,
+				struct file *filp, poll_table *wait)
+{
+	struct anybuss_host *cd = client->host;
+	unsigned int mask = POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM;
+
+	poll_wait(filp, &cd->dc_wq, wait);
+	/* data changed ? */
+	if (atomic_read(&cd->dc_event) != dc_event)
+		mask |= POLLPRI | POLLERR;
+	return mask;
+}
+EXPORT_SYMBOL_GPL(anybuss_poll);
+
+int anybuss_send_msg(struct anybuss_client *client, u16 cmd_num,
+				const void *buf, size_t count)
+{
+	struct anybuss_host *cd = client->host;
+
+	return _anybus_mbox_cmd(cd, cmd_num, true, buf, count, NULL, 0,
+					NULL, 0);
+}
+EXPORT_SYMBOL_GPL(anybuss_send_msg);
+
+int anybuss_send_ext(struct anybuss_client *client, u16 cmd_num,
+	const void *buf, size_t count)
+{
+	struct anybuss_host *cd = client->host;
+
+	return _anybus_mbox_cmd(cd, cmd_num, true, NULL, 0, NULL, 0,
+					buf, count);
+}
+EXPORT_SYMBOL_GPL(anybuss_send_ext);
+
+int anybuss_recv_msg(struct anybuss_client *client, u16 cmd_num,
+	void *buf, size_t count)
+{
+	struct anybuss_host *cd = client->host;
+
+	return _anybus_mbox_cmd(cd, cmd_num, true, NULL, 0, buf, count,
+					NULL, 0);
+}
+EXPORT_SYMBOL_GPL(anybuss_recv_msg);
+
+/* ------------------------ bus functions ------------------------ */
+
+static int anybus_bus_match(struct device *dev,
+				struct device_driver *drv)
+{
+	struct anybuss_client_driver *adrv =
+		to_anybuss_client_driver(drv);
+	struct anybuss_client *adev =
+		to_anybuss_client(dev);
+
+	return adrv->fieldbus_type == adev->fieldbus_type;
+}
+
+static int anybus_bus_probe(struct device *dev)
+{
+	struct anybuss_client_driver *adrv =
+		to_anybuss_client_driver(dev->driver);
+	struct anybuss_client *adev =
+		to_anybuss_client(dev);
+
+	if (!adrv->probe)
+		return -ENODEV;
+	return adrv->probe(adev);
+}
+
+static int anybus_bus_remove(struct device *dev)
+{
+	struct anybuss_client_driver *adrv =
+		to_anybuss_client_driver(dev->driver);
+
+	if (adrv->remove)
+		return adrv->remove(to_anybuss_client(dev));
+	return 0;
+}
+
+static struct bus_type anybus_bus = {
+	.name		= "anybuss",
+	.match		= anybus_bus_match,
+	.probe		= anybus_bus_probe,
+	.remove		= anybus_bus_remove,
+};
+
+int anybuss_client_driver_register(struct anybuss_client_driver *drv)
+{
+	drv->driver.bus = &anybus_bus;
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(anybuss_client_driver_register);
+
+void anybuss_client_driver_unregister(struct anybuss_client_driver *drv)
+{
+	return driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(anybuss_client_driver_unregister);
+
+/* ------------------------ attributes ------------------------ */
+
+static ssize_t state_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct anybuss_host *cd = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n",
+		atomic_read(&cd->fieldbus_online) ?
+			"online" : "offline");
+}
+
+static DEVICE_ATTR_RO(state);
+
+static struct attribute *ctrl_attrs[] = {
+	&dev_attr_state.attr,
+	NULL
+};
+
+static struct attribute_group ctrl_group = { .attrs = ctrl_attrs };
+
+static void client_device_release(struct device *dev)
+{
+	kfree(to_anybuss_client(dev));
+}
+
+static int taskq_alloc(struct device *dev, struct kfifo *q)
+{
+	void *buf;
+	size_t size = 64 * sizeof(struct ab_task *);
+
+	buf = devm_kzalloc(dev, size, GFP_KERNEL);
+	if (!buf)
+		return -EIO;
+	return kfifo_init(q, buf, size);
+}
+
+static int anybus_host_probe(struct platform_device *pdev)
+{
+	int ret, i;
+	u8 val[4];
+	u16 fieldbus_type;
+	struct anybuss_host *cd;
+	struct device *dev = &pdev->dev;
+	struct device *parent = dev->parent;
+	struct resource *res;
+	struct anybuss_host_pdata *pdata =
+				dev_get_platdata(&pdev->dev);
+
+	if (!pdata) {
+		dev_err(dev, "need platform data");
+		return -EINVAL;
+	}
+	if (!pdev->dev.parent) {
+		dev_err(dev, "need parent device");
+		return -EINVAL;
+	}
+	cd = devm_kzalloc(dev, sizeof(*cd), GFP_KERNEL);
+	if (!cd)
+		return -ENOMEM;
+	cd->dev = dev;
+	cd->parent = parent;
+	init_completion(&cd->card_boot);
+	init_waitqueue_head(&cd->wq);
+	init_waitqueue_head(&cd->dc_wq);
+	for (i = 0; i < ARRAY_SIZE(cd->qs); i++) {
+		ret = taskq_alloc(dev, &cd->qs[i]);
+		if (ret)
+			return ret;
+	}
+	if (WARN_ON(ARRAY_SIZE(cd->qs) < 3))
+		return -EINVAL;
+	cd->powerq = &cd->qs[0];
+	cd->mboxq = &cd->qs[1];
+	cd->areaq = &cd->qs[2];
+	cd->reset = pdata->reset;
+	cd->regmap = pdata->regmap;
+	spin_lock_init(&cd->qlock);
+	atomic_set(&cd->dc_event, 0);
+	atomic_set(&cd->fieldbus_online, 0);
+	cd->qcache = kmem_cache_create(dev_name(dev),
+		sizeof(struct ab_task), 0, 0, NULL);
+	if (!cd->qcache)
+		return -ENOMEM;
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res) {
+		dev_err(dev, "need irq resource");
+		ret = -ENOENT;
+		goto err_qcache;
+	}
+	cd->irq = res->start;
+	/* use a dpram test to check if a card is present, this is only
+	 * possible while in reset.
+	 */
+	cd->reset(parent, true);
+	if (test_dpram(cd->regmap)) {
+		dev_err(dev, "no Anybus-S card in slot");
+		ret = -ENODEV;
+		goto err_qcache;
+	}
+	ret = request_irq(cd->irq, irq_handler, IRQF_TRIGGER_LOW,
+			dev_name(dev), cd);
+	if (ret) {
+		dev_err(dev, "could not request irq");
+		goto err_qcache;
+	}
+	/* startup sequence:
+	 *   perform dummy IND_AB read to prevent false 'init done' irq
+	 *     (already done by test_dpram() above)
+	 *   release reset
+	 *   wait for first interrupt
+	 *   interrupt came in: ready to go !
+	 */
+	cd->reset(parent, false);
+	ret = wait_for_completion_timeout(&cd->card_boot, TIMEOUT);
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+	if (ret < 0)
+		goto err_irq;
+	/* according to the anybus docs, we're allowed to read these
+	 * without handshaking / reserving the area
+	 */
+	dev_info(dev, "Anybus-S card detected");
+	regmap_bulk_read(cd->regmap, REG_BOOTLOADER_V, val, 2);
+	dev_info(dev, "Bootloader version: %02X%02X",
+			val[0], val[1]);
+	regmap_bulk_read(cd->regmap, REG_API_V, val, 2);
+	dev_info(dev, "API version: %02X%02X", val[0], val[1]);
+	regmap_bulk_read(cd->regmap, REG_FIELDBUS_V, val, 2);
+	dev_info(dev, "Fieldbus version: %02X%02X", val[0], val[1]);
+	regmap_bulk_read(cd->regmap, REG_SERIAL_NO, val, 4);
+	dev_info(dev, "Serial number: %02X%02X%02X%02X",
+		val[0], val[1], val[2], val[3]);
+	regmap_bulk_read(cd->regmap, REG_FIELDBUS_TYPE, &fieldbus_type,
+				sizeof(fieldbus_type));
+	fieldbus_type = be16_to_cpu(fieldbus_type);
+	dev_info(dev, "Fieldbus type: %04X", fieldbus_type);
+	regmap_bulk_read(cd->regmap, REG_MODULE_SW_V, val, 2);
+	dev_info(dev, "Module SW version: %02X%02X",
+		val[0], val[1]);
+	/* put card back reset until a client driver releases it */
+	disable_irq(cd->irq);
+	cd->reset(parent, true);
+	atomic_set(&cd->ind_ab, IND_AB_UPDATED);
+	/* attributes */
+	ret = sysfs_create_group(&dev->kobj, &ctrl_group);
+	if (ret < 0)
+		goto err_irq;
+	cd->fieldbus_online_sd =
+		sysfs_get_dirent(dev->kobj.sd, "state");
+	if (!cd->fieldbus_online_sd) {
+		ret = -ENODEV;
+		goto err_sysfs;
+	}
+	/* fire up the queue thread */
+	cd->qthread = kthread_run(qthread_fn, cd, dev_name(dev));
+	if (IS_ERR(cd->qthread)) {
+		dev_err(dev, "could not create kthread");
+		ret = PTR_ERR(cd->qthread);
+		goto err_dirent;
+	}
+	/* now advertise that we've detected a client device (card).
+	 * the bus infrastructure will match it to a client driver.
+	 */
+	cd->client = kzalloc(sizeof(*cd->client), GFP_KERNEL);
+	if (!cd->client) {
+		ret = -ENOMEM;
+		goto err_kthread;
+	}
+	cd->client->fieldbus_type = fieldbus_type;
+	cd->client->host = cd;
+	cd->client->dev.bus = &anybus_bus;
+	cd->client->dev.parent = dev;
+	cd->client->dev.id = pdev->id;
+	cd->client->dev.release = client_device_release;
+	dev_set_name(&cd->client->dev, "%s.card0",
+				dev_name(&pdev->dev));
+	ret = device_register(&cd->client->dev);
+	if (ret)
+		goto err_client;
+	platform_set_drvdata(pdev, cd);
+	dev_set_drvdata(dev, cd);
+	return 0;
+err_client:
+	put_device(&cd->client->dev);
+err_kthread:
+	kthread_stop(cd->qthread);
+err_dirent:
+	sysfs_put(cd->fieldbus_online_sd);
+err_sysfs:
+	sysfs_remove_group(&dev->kobj, &ctrl_group);
+err_irq:
+	free_irq(cd->irq, cd);
+	cd->reset(parent, true);
+err_qcache:
+	kmem_cache_destroy(cd->qcache);
+	return ret;
+}
+
+static int anybus_host_remove(struct platform_device *pdev)
+{
+	struct anybuss_host *cd = platform_get_drvdata(pdev);
+
+	device_unregister(&cd->client->dev);
+	kthread_stop(cd->qthread);
+	sysfs_put(cd->fieldbus_online_sd);
+	sysfs_remove_group(&cd->dev->kobj, &ctrl_group);
+	free_irq(cd->irq, cd);
+	cd->reset(cd->parent, true);
+	kmem_cache_destroy(cd->qcache);
+	return 0;
+}
+
+static struct platform_driver anybus_host_driver = {
+	.probe = anybus_host_probe,
+	.remove = anybus_host_remove,
+	.driver	= {
+		.name = "anybuss-host",
+	},
+};
+
+static int __init anybus_init(void)
+{
+	int ret;
+
+	ret = bus_register(&anybus_bus);
+	if (ret) {
+		pr_err("could not register Anybus-S bus: %d\n", ret);
+		return ret;
+	}
+	return platform_driver_register(&anybus_host_driver);
+}
+module_init(anybus_init);
+
+static void __exit anybus_exit(void)
+{
+	platform_driver_unregister(&anybus_host_driver);
+	bus_unregister(&anybus_bus);
+}
+module_exit(anybus_exit);
+
+MODULE_DESCRIPTION("HMS Anybus-S Host Driver");
+MODULE_AUTHOR("Sven Van Asbroeck <svendev@arcx.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/anybuss-client.h b/include/linux/anybuss-client.h
new file mode 100644
index 000000000000..9d439d1a496f
--- /dev/null
+++ b/include/linux/anybuss-client.h
@@ -0,0 +1,100 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Anybus-S client adapter definitions
+ *
+ * Copyright 2018 Arcx Inc
+ */
+
+#ifndef __LINUX_ANYBUSS_CLIENT_H__
+#define __LINUX_ANYBUSS_CLIENT_H__
+
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/poll.h>
+
+struct anybuss_host;
+
+struct anybuss_client {
+	struct device dev;
+	struct anybuss_host *host;
+	u16 fieldbus_type;
+};
+
+struct anybuss_client_driver {
+	struct device_driver driver;
+	int (*probe)(struct anybuss_client *adev);
+	int (*remove)(struct anybuss_client *adev);
+	u16 fieldbus_type;
+};
+
+int anybuss_client_driver_register(struct anybuss_client_driver *drv);
+void anybuss_client_driver_unregister(
+				struct anybuss_client_driver *drv);
+
+static inline struct anybuss_client *to_anybuss_client(
+					struct device *dev)
+{
+	return container_of(dev, struct anybuss_client, dev);
+}
+
+static inline struct anybuss_client_driver *to_anybuss_client_driver(
+					struct device_driver *drv)
+{
+	return container_of(drv, struct anybuss_client_driver, driver);
+}
+
+static inline void *
+anybuss_get_drvdata(const struct anybuss_client *client)
+{
+	return dev_get_drvdata(&client->dev);
+}
+
+static inline void
+anybuss_set_drvdata(struct anybuss_client *client, void *data)
+{
+	dev_set_drvdata(&client->dev, data);
+}
+
+int anybuss_set_power(struct anybuss_client *client, bool power_on);
+
+enum anybuss_offl_mode {
+	AB_OFFL_MODE_CLEAR = 0,
+	AB_OFFL_MODE_FREEZE,
+	AB_OFFL_MODE_SET
+};
+
+struct anybuss_memcfg {
+	u16 input_io;
+	u16 input_dpram;
+	u16 input_total;
+
+	u16 output_io;
+	u16 output_dpram;
+	u16 output_total;
+
+	enum anybuss_offl_mode offl_mode;
+};
+
+int anybuss_start_init(struct anybuss_client *client,
+			const struct anybuss_memcfg *cfg);
+int anybuss_finish_init(struct anybuss_client *client);
+int anybuss_read_fbctrl(struct anybuss_client *client, u16 addr,
+				void *buf, size_t count);
+int anybuss_send_msg(struct anybuss_client *client, u16 cmd_num,
+	const void *buf, size_t count);
+int anybuss_send_ext(struct anybuss_client *client, u16 cmd_num,
+	const void *buf, size_t count);
+int anybuss_recv_msg(struct anybuss_client *client, u16 cmd_num,
+	void *buf, size_t count);
+
+/* these help clients make a struct file_operations */
+int anybuss_write_input(struct anybuss_client *client,
+				const char __user *buf, size_t size,
+				loff_t *offset);
+int anybuss_read_output(struct anybuss_client *client, int *dc_event,
+				char __user *buf, size_t size,
+				loff_t *offset);
+unsigned int anybuss_poll(struct anybuss_client *client,
+		int dc_event, struct file *filp, poll_table *wait);
+
+#endif /* __LINUX_ANYBUSS_CLIENT_H__ */
-- 
2.17.1

[PATCH anybus v1 3/4] bus: support HMS Anybus-S bus.

[Randy Dunlap]

On 10/24/18 7:24 AM, Sven Van Asbroeck wrote:
> diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
> index 1851112ccc29..68869648b9ab 100644
> --- a/drivers/bus/Kconfig
> +++ b/drivers/bus/Kconfig
> @@ -45,6 +45,17 @@ config IMX_WEIM
>  	  The WEIM(Wireless External Interface Module) works like a bus.
>  	  You can attach many different devices on it, such as NOR, onenand.
>  
> +config HMS_ANYBUSS_HOST
> +	tristate "HMS Anybus-S Host/Bus Driver"
> +	select REGMAP
> +	depends on OF
> +	default n

Please drop the "default n".  That is already the default in Kconfig files.

> +	help
> +	  Driver for the HMS Industrial Networks Anybus-S bus.
> +	  You can attach Anybus-S compatible cards to it, which
> +	  typically provide fieldbus and industrial ethernet
> +	  functionality.
> +
>  config MIPS_CDMM
>  	bool "MIPS Common Device Memory Map (CDMM) Driver"
>  	depends on CPU_MIPSR2


Also please check the multi-line comments for kernel comment style.

thanks,
-- 
~Randy

Re: [PATCH anybus v1 3/4] bus: support HMS Anybus-S bus.

[Linus Walleij]

Hi Sven,

thanks for your patch!

On Wed, Oct 24, 2018 at 4:25 PM Sven Van Asbroeck <svendev@arcx.com> wrote:

> This driver implementation is designed to be almost completely independent
> from the way the Anybus-S hardware is accessed by the SoC. All it needs is:
>
> - a regmap which accesses the underlying Anybus-S dpram by whatever means;
> - an interrupt line, ultimately connected to the Anybus-S card;
> - a reset function.

Overall this commit message is a good start! You explain what this thing is
and what it does.

What you need to add is a bit of how the driver is architected. That can also
be added as comment in the header of the driver file, maybe that is even
better, i.e. here:

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HMS Anybus-S Host Driver

<architecture description goes here>

This is really needed because the driver is starting threads and
running completions and tasks and whatnot to the left and
right, and when random people come in to maintain this code they
will be puzzled. You need an overarching description of how the
driver is constructed here.

Please add proper kerneldoc to the struct anybus_host
also "buss" is a germanism isn't it?  It should be just "anybus"?

> +struct anybuss_host {
> +       struct device *dev;
> +       struct device *parent;
> +       struct anybuss_client *client;

There as well?

Just search/replace "s/buss/bus/g" everywhere I suspect.

> +static irqreturn_t irq_handler(int irq, void *data)
> +{
> +       struct anybuss_host *cd = data;
> +       int ind_ab;
> +
> +       /* reading the anybus indicator register acks the interrupt */
> +       ind_ab = read_ind_ab(cd->regmap);
> +       if (ind_ab < 0)
> +               return IRQ_NONE;
> +       atomic_set(&cd->ind_ab, ind_ab);
> +       complete(&cd->card_boot);
> +       wake_up(&cd->wq);
> +       return IRQ_HANDLED;
> +}

It looks a bit like you reinvent threaded interrupts but enlighten me
on the architecture and I might be able to get it.

> +static int task_fn_power_on_2(struct anybuss_host *cd,
> +                               struct ab_task *t)
> +{
> +       if (completion_done(&cd->card_boot)) {
> +               cd->power_on = true;
> +               return 0;
> +       }
> +       if (time_after(jiffies, t->start_jiffies + TIMEOUT)) {
> +               disable_irq(cd->irq);
> +               ab_reset(cd, true);
> +               dev_err(cd->dev, "power on timed out");
> +               return -ETIMEDOUT;
> +       }
> +       return -EINPROGRESS;
> +}
> +
> +static int task_fn_power_on(struct anybuss_host *cd,
> +                               struct ab_task *t)
> +{
> +       unsigned int dummy;
> +
> +       if (cd->power_on)
> +               return 0;
> +       /* anybus docs: prevent false 'init done' interrupt by
> +        * doing a dummy read of IND_AB register while in reset.
> +        */
> +       regmap_read(cd->regmap, REG_IND_AB, &dummy);
> +       reinit_completion(&cd->card_boot);
> +       enable_irq(cd->irq);
> +       ab_reset(cd, false);
> +       t->task_fn = task_fn_power_on_2;
> +       return -EINPROGRESS;
> +}

This looks complex. Why can't you just sleep() and then
retry this instead of shuffleing around different "tasks"?
Are you actually modeling a state machine? In that case
I can kind of understand it, then you just need one
thread/work and assign it an enum of states or
something, maybe name that "state" rather than task
so we see what is going on.

> +static int task_fn_area_3(struct anybuss_host *cd, struct ab_task *t)
> +static int task_fn_area_2(struct anybuss_host *cd, struct ab_task *t)
> +static int task_fn_area(struct anybuss_host *cd, struct ab_task *t)
> +static struct ab_task *
> +create_area_reader(struct kmem_cache *qcache, u16 flags, u16 addr,
> +                               size_t count)
> +static struct ab_task *
> +create_area_writer(struct kmem_cache *qcache, u16 flags, u16 addr,
> +                               const void *buf, size_t count)
> +static struct ab_task *
> +create_area_user_writer(struct kmem_cache *qcache, u16 flags, u16 addr,
> +                               const void __user *buf, size_t count)

So there are many different tasks going on.

Are they just created to get something going in process context?

> +static void softint_ack(struct anybuss_host *cd)
> +static void process_softint(struct anybuss_host *cd)

This looks like MSI (message signalled interrupt) and makes me think
that you should probably involve the irqchip maintainers. Interrupts
shall be represented in the irqchip abstraction.

> +int anybuss_client_driver_register(struct anybuss_client_driver *drv)
> +{
> +       drv->driver.bus = &anybus_bus;
> +       return driver_register(&drv->driver);
> +}

There is nice use of the bus abstractions here.

> +       cd->reset = pdata->reset;

This callback thing to handle reset doesn't seem right.

The kernel has a reset for assert/deassert och just assert()
reset handling that you can find in
drivers/reset/*

Maybe that is what you should be using instead of
rolling your own reset handling?

> +       cd->reset(parent, true);

So this would just be something like
#include <linux/reset.h>

r = devm_reset_control_get_exclusive(dev, id);
ret = reset_control_assert(r);

> +       regmap_bulk_read(cd->regmap, REG_SERIAL_NO, val, 4);
> +       dev_info(dev, "Serial number: %02X%02X%02X%02X",
> +               val[0], val[1], val[2], val[3]);

This looks like device-unique data so please do this:

#include <linux/random.h>

add_device_randomness(val, 4);

I guess I can provide better review once you add some
information on this task state machine business and how
it is engineered, looking forward to the next iteration!

Yours,
Linus Walleij

[PATCH anybus v1 4/4] misc: support HMS Profinet IRT industrial controller.

[Sven Van Asbroeck]

The Anybus-S PROFINET IRT communication module provides instant integration
to any Ethernet based LAN via SMTP, FTP, HTTP as well as PROFINET and
Modbus-TCP. Additional protocols can be implemented on top of TCP/IP
or UDP using the transparent socket interface.

Official documentation:
https://www.anybus.com/docs/librariesprovider7/default-document-library
/manuals-design-guides/hms-hmsi-168-52.pdf

This implementation is an Anybus-S client driver, designed to be
instantiated by the Anybus-S bus driver when it discovers the Profinet
card.

If loaded successfully, the driver creates a /dev/profinet%d devnode,
and a /sys/class/misc/profinet%d sysfs subdir:
- the card can be configured with a single, atomic ioctl on the devnode;
- the card's internal dpram is accessed by calling read/write/seek
    on the devnode.
- the card's "fieldbus specific area" properties can be accessed via
    the sysfs dir.

Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
---
 drivers/misc/Kconfig              |  11 +
 drivers/misc/Makefile             |   1 +
 drivers/misc/hms-profinet.c       | 747 ++++++++++++++++++++++++++++++
 include/uapi/linux/hms-common.h   |  14 +
 include/uapi/linux/hms-profinet.h | 101 ++++
 5 files changed, 874 insertions(+)
 create mode 100644 drivers/misc/hms-profinet.c
 create mode 100644 include/uapi/linux/hms-common.h
 create mode 100644 include/uapi/linux/hms-profinet.h

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 3726eacdf65d..377fea2e3003 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -406,6 +406,17 @@ config SPEAR13XX_PCIE_GADGET
 	 entry will be created for that controller. User can use these
 	 sysfs node to configure PCIe EP as per his requirements.
 
+config HMS_PROFINET
+	tristate "HMS Profinet IRT Controller (Anybus-S)"
+	select HMS_ANYBUSS_HOST
+	default n
+	help
+	 If you say yes here you get support for the HMS Industrial
+	 Networks Profinet IRT Controller.
+	 This driver can also be built as a module. If so, the module
+	 will be called hms-profinet.
+	 If unsure, say N.
+
 config VMWARE_BALLOON
 	tristate "VMware Balloon Driver"
 	depends on VMWARE_VMCI && X86 && HYPERVISOR_GUEST
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index af22bbc3d00c..dcf0468187b6 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_SENSORS_TSL2550)	+= tsl2550.o
 obj-$(CONFIG_DS1682)		+= ds1682.o
 obj-$(CONFIG_C2PORT)		+= c2port/
 obj-$(CONFIG_HMC6352)		+= hmc6352.o
+obj-$(CONFIG_HMS_PROFINET)	+= hms-profinet.o
 obj-y				+= eeprom/
 obj-y				+= cb710/
 obj-$(CONFIG_SPEAR13XX_PCIE_GADGET)	+= spear13xx_pcie_gadget.o
diff --git a/drivers/misc/hms-profinet.c b/drivers/misc/hms-profinet.c
new file mode 100644
index 000000000000..7338a49cbddd
--- /dev/null
+++ b/drivers/misc/hms-profinet.c
@@ -0,0 +1,747 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HMS Profinet Client Driver
+ *
+ * Copyright (C) 2018 Arcx Inc
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <linux/miscdevice.h>
+
+#include <linux/anybuss-client.h>
+#include <uapi/linux/hms-profinet.h>
+
+#define PROFI_DPRAM_SIZE	512
+
+/* --------------------------------------------------------------
+ * Anybus Profinet mailbox messages - definitions
+ * --------------------------------------------------------------
+ */
+
+/* note that we're depending on the layout of these structures being
+ * exactly as advertised - which means they need to be packed.
+ */
+
+struct msgEthConfig {
+	u32 ip_addr, subnet_msk, gateway_addr;
+} __packed;
+
+struct msgMacAddr {
+	u8 addr[6];
+} __packed;
+
+struct msgStr {
+	char	s[128];
+} __packed;
+
+struct msgShortStr {
+	char	s[64];
+} __packed;
+
+struct msgHicp {
+	char	enable;
+} __packed;
+
+/* --------------------------------------------------------------
+ * Fieldbus Specific Area - memory locations
+ * --------------------------------------------------------------
+ */
+#define FSA_NETWORK_STATUS	0x700
+#define FSA_LAYER_STATUS	0x7B2
+#define FSA_IO_CTRL_STATUS	0x7B0
+#define FSA_LAYER_FAULT_CODE	0x7B4
+
+struct profi_priv {
+	struct anybuss_client *client;
+	int id;
+	atomic_t refcount;
+	char node_name[16];
+	struct miscdevice misc;
+	struct device *dev;	/* just a link to the misc device */
+	struct mutex enable_lock;
+};
+
+static int profinet_configure(struct anybuss_client *ab,
+				struct ProfinetConfig *cfg)
+{
+	int ret;
+
+	if (cfg->eth.is_valid) {
+		struct msgEthConfig msg = {
+			.ip_addr = cfg->eth.ip_addr,
+			.subnet_msk = cfg->eth.subnet_msk,
+			.gateway_addr = cfg->eth.gateway_addr,
+		};
+		ret = anybuss_send_msg(ab, 0x0001, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->dev_id.is_valid) {
+		u16 ext[2] = {
+			cpu_to_be16(cfg->dev_id.vendorid),
+			cpu_to_be16(cfg->dev_id.deviceid)
+		};
+		ret = anybuss_send_ext(ab, 0x0102, ext, sizeof(ext));
+		if (ret)
+			return ret;
+	}
+	if (cfg->station_name.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->station_name.name, sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0103, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->station_type.is_valid) {
+		struct msgShortStr msg = { 0 };
+
+		strncpy(msg.s, cfg->station_type.name, sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0104, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->mac_addr.is_valid) {
+		struct msgMacAddr msg = { 0 };
+
+		memcpy(msg.addr, cfg->mac_addr.addr, sizeof(msg.addr));
+		ret = anybuss_send_msg(ab, 0x0019, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->host_domain.is_valid) {
+		size_t len;
+		struct msgStr msg = { 0 };
+		/* check if host and domain names fit in msg structure
+		 */
+		len =	strnlen(cfg->host_domain.hostname,
+				sizeof(cfg->host_domain.hostname))
+					+ 1 +
+			strnlen(cfg->host_domain.domainname,
+				sizeof(cfg->host_domain.domainname))
+					+ 1;
+		if (len > sizeof(msg.s))
+			return -ENAMETOOLONG;
+		strncpy(msg.s, cfg->host_domain.hostname,
+			sizeof(msg.s));
+		len = strnlen(msg.s, sizeof(msg.s)) + 1; /* NULL term */
+		strncpy(msg.s + len, cfg->host_domain.domainname,
+				sizeof(msg.s) - len);
+		ret = anybuss_send_msg(ab, 0x0032, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->hicp.is_valid) {
+		struct msgHicp msg = {
+			.enable = cfg->hicp.enable ? 1 : 0,
+		};
+		ret = anybuss_send_msg(ab, 0x0013, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->web_server.is_valid) {
+		ret = anybuss_send_msg(ab,
+			cfg->web_server.enable ? 0x0005 : 0x0004,
+			NULL, 0);
+		if (ret)
+			return ret;
+	}
+	if (cfg->ftp_server.disable) {
+		ret = anybuss_send_msg(ab, 0x0006, NULL, 0);
+		if (ret)
+			return ret;
+	}
+	if (cfg->global_admin_mode.enable) {
+		ret = anybuss_send_msg(ab, 0x000B, NULL, 0);
+		if (ret)
+			return ret;
+	}
+	if (cfg->vfs.disable) {
+		ret = anybuss_send_msg(ab, 0x0011, NULL, 0);
+		if (ret)
+			return ret;
+	}
+	if (cfg->stop_mode.is_valid) {
+		u16 action;
+
+		switch (cfg->stop_mode.action) {
+		case HMS_SMA_CLEAR:
+			action = 0;
+			break;
+		case HMS_SMA_FREEZE:
+			action = 1;
+			break;
+		case HMS_SMA_SET:
+			action = 2;
+			break;
+		default:
+			return -EINVAL;
+		}
+		action = cpu_to_be16(action);
+		ret = anybuss_send_ext(ab, 0x0101, &action,
+						sizeof(action));
+		if (ret)
+			return ret;
+	}
+	if (cfg->snmp_system_descr.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->snmp_system_descr.description,
+					sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0120, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->snmp_iface_descr.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->snmp_iface_descr.description,
+					sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0121, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->mib2_system_descr.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->mib2_system_descr.description,
+					sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0124, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->mib2_system_contact.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->mib2_system_contact.contact,
+					sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0125, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	if (cfg->mib2_system_location.is_valid) {
+		struct msgStr msg = { 0 };
+
+		strncpy(msg.s, cfg->mib2_system_location.location,
+					sizeof(msg.s));
+		ret = anybuss_send_msg(ab, 0x0126, &msg, sizeof(msg));
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int profinet_enable(struct profi_priv *priv,
+				struct ProfinetConfig *cfg)
+{
+	int ret;
+	struct anybuss_client *client = priv->client;
+
+	/* Initialization Sequence, Generic Anybus Mode */
+	const struct anybuss_memcfg mem_cfg = {
+		.input_io = 220,
+		.input_dpram = PROFI_DPRAM_SIZE,
+		.input_total = PROFI_DPRAM_SIZE,
+		.output_io = 220,
+		.output_dpram = PROFI_DPRAM_SIZE,
+		.output_total = PROFI_DPRAM_SIZE,
+		.offl_mode = AB_OFFL_MODE_CLEAR,
+	};
+	if (mutex_lock_interruptible(&priv->enable_lock))
+		return -ERESTARTSYS;
+	/* switch anybus off then on, this ensures we can do a complete
+	 * configuration cycle in case anybus was already on.
+	 */
+	anybuss_set_power(client, false);
+	ret = anybuss_set_power(client, true);
+	if (ret)
+		goto err_init;
+	ret = anybuss_start_init(client, &mem_cfg);
+	if (ret)
+		goto err_init;
+	if (cfg)
+		ret = profinet_configure(client, cfg);
+	if (ret)
+		goto err_init;
+	ret = anybuss_finish_init(client);
+	if (ret)
+		goto err_init;
+	mutex_unlock(&priv->enable_lock);
+	return 0;
+err_init:
+	anybuss_set_power(client, false);
+	mutex_unlock(&priv->enable_lock);
+	return ret;
+}
+
+static int profinet_disable(struct profi_priv *priv)
+{
+	int ret;
+
+	if (mutex_lock_interruptible(&priv->enable_lock))
+		return -ERESTARTSYS;
+	ret = anybuss_set_power(priv->client, false);
+	mutex_unlock(&priv->enable_lock);
+	return ret;
+}
+
+static int fbctrl_readw(struct anybuss_client *client, u16 addr)
+{
+	int ret;
+	u16 val;
+
+	ret = anybuss_read_fbctrl(client, addr, &val, sizeof(val));
+	if (ret < 0)
+		return ret;
+	return (int)be16_to_cpu(val);
+}
+
+static ssize_t mac_addr_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgMacAddr response;
+	int ret;
+
+	ret = anybuss_recv_msg(priv->client, 0x0010, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	return snprintf(buf, PAGE_SIZE, "%02X:%02X:%02X:%02X:%02X:%02X\n",
+		response.addr[0], response.addr[1],
+		response.addr[2], response.addr[3],
+		response.addr[4], response.addr[5]);
+}
+
+static DEVICE_ATTR_RO(mac_addr);
+
+static ssize_t start_defaults_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	unsigned long num;
+
+	if (kstrtoul(buf, 0, &num))
+		return -EINVAL;
+	if (num)
+		profinet_enable(priv, NULL);
+	return count;
+}
+
+static DEVICE_ATTR_WO(start_defaults);
+
+static ssize_t ip_addr_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgEthConfig response;
+	int ret;
+
+	ret = anybuss_recv_msg(priv->client, 0x0002, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
+		response.ip_addr & 0xFF,
+		(response.ip_addr >>  8) & 0xFF,
+		(response.ip_addr >> 16) & 0xFF,
+		(response.ip_addr >> 24) & 0xFF);
+}
+
+static DEVICE_ATTR_RO(ip_addr);
+
+static ssize_t subnet_mask_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgEthConfig response;
+	int ret;
+
+	ret = anybuss_recv_msg(priv->client, 0x0002, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
+		response.subnet_msk & 0xFF,
+		(response.subnet_msk >>  8) & 0xFF,
+		(response.subnet_msk >> 16) & 0xFF,
+		(response.subnet_msk >> 24) & 0xFF);
+}
+
+static DEVICE_ATTR_RO(subnet_mask);
+
+static ssize_t gateway_addr_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgEthConfig response;
+	int ret;
+
+	ret = anybuss_recv_msg(priv->client, 0x0002, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
+		response.gateway_addr & 0xFF,
+		(response.gateway_addr >>  8) & 0xFF,
+		(response.gateway_addr >> 16) & 0xFF,
+		(response.gateway_addr >> 24) & 0xFF);
+}
+
+static DEVICE_ATTR_RO(gateway_addr);
+
+static ssize_t hostname_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgStr response;
+	int ret;
+
+	ret = anybuss_recv_msg(priv->client, 0x0034, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	return snprintf(buf, PAGE_SIZE, "%s\n", response.s);
+}
+
+static DEVICE_ATTR_RO(hostname);
+
+static ssize_t domainname_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	struct msgStr response;
+	int ret, pos;
+
+	ret = anybuss_recv_msg(priv->client, 0x0034, &response,
+						sizeof(response));
+	if (ret)
+		return ret;
+	/* domain name string located right behind null-terminated
+	 * host name string.
+	 */
+	pos = strnlen(response.s, sizeof(response.s)) + 1;
+	if (pos >= sizeof(response.s))
+		return -ENAMETOOLONG;
+	return snprintf(buf, PAGE_SIZE, "%s\n", response.s + pos);
+}
+
+static DEVICE_ATTR_RO(domainname);
+
+static ssize_t network_link_on_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	int ns;
+
+	ns = fbctrl_readw(priv->client, FSA_NETWORK_STATUS);
+	if (ns < 0)
+		return ns;
+	return snprintf(buf, PAGE_SIZE, "%d\n", ns & 1);
+}
+
+static DEVICE_ATTR_RO(network_link_on);
+
+static ssize_t network_ip_in_use_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	int ns;
+
+	ns = fbctrl_readw(priv->client, FSA_NETWORK_STATUS);
+	if (ns < 0)
+		return ns;
+	return snprintf(buf, PAGE_SIZE, "%d\n", (ns>>1) & 1);
+}
+
+static DEVICE_ATTR_RO(network_ip_in_use);
+
+static ssize_t layer_status_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	const char *s;
+	int ls;
+
+	ls = fbctrl_readw(priv->client, FSA_LAYER_STATUS);
+	if (ls < 0)
+		return ls;
+	switch (ls) {
+	case 0x0000:
+		s = "not yet initialized";
+		break;
+	case 0x0001:
+		s = "successfully initialized";
+		break;
+	case 0x0002:
+		s = "failed to initialize";
+		break;
+	default:
+		return -EINVAL;
+	}
+	return snprintf(buf, PAGE_SIZE, "%s\n", s);
+}
+
+static DEVICE_ATTR_RO(layer_status);
+
+static ssize_t io_controller_status_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct profi_priv *priv = dev_get_drvdata(dev);
+	const char *s;
+	int w;
+
+	w = fbctrl_readw(priv->client, FSA_IO_CTRL_STATUS);
+	if (w < 0)
+		return w;
+	switch (w) {
+	case 0x0000:
+		s = "No connection made";
+		break;
+	case 0x0001:
+		s = "STOP";
+		break;
+	case 0x0002:
+		s = "RUN";
+		break;
+	case 0x0004:
+		s = "STATION OK";
+		break;
+	case 0x0008:
+		s = "STATION PROBLEM";
+		break;
+	case 0x0010:
+		s = "PRIMARY";
+		break;
+	case 0x0020:
+		s = "BACKUP";
+		break;
+	default:
+		return -EINVAL;
+	}
+	return snprintf(buf, PAGE_SIZE, "%s\n", s);
+}
+
+static DEVICE_ATTR_RO(io_controller_status);
+
+static ssize_t layer_fault_code_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	int fc;
+	struct profi_priv *priv = dev_get_drvdata(dev);
+
+	fc = fbctrl_readw(priv->client, FSA_LAYER_FAULT_CODE);
+	if (fc < 0)
+		return fc;
+	return snprintf(buf, PAGE_SIZE, "%d\n", fc);
+}
+
+static DEVICE_ATTR_RO(layer_fault_code);
+
+static struct attribute *ctrl_attrs[] = {
+	&dev_attr_mac_addr.attr,
+	&dev_attr_start_defaults.attr,
+	&dev_attr_ip_addr.attr,
+	&dev_attr_subnet_mask.attr,
+	&dev_attr_gateway_addr.attr,
+	&dev_attr_hostname.attr,
+	&dev_attr_domainname.attr,
+	&dev_attr_network_link_on.attr,
+	&dev_attr_network_ip_in_use.attr,
+	&dev_attr_io_controller_status.attr,
+	&dev_attr_layer_status.attr,
+	&dev_attr_layer_fault_code.attr,
+	NULL
+};
+
+static struct attribute_group ctrl_group = { .attrs = ctrl_attrs };
+
+struct profi_open_file {
+	struct profi_priv *priv;
+	int event;
+};
+
+static int profi_open(struct inode *node, struct file *filp)
+{
+	struct profi_open_file *of;
+	struct profi_priv *priv = container_of(filp->private_data,
+					struct profi_priv, misc);
+
+	of = kzalloc(sizeof(*of), GFP_KERNEL);
+	if (!of)
+		return -ENOMEM;
+	of->priv = priv;
+	filp->private_data = of;
+	atomic_inc(&priv->refcount);
+	return 0;
+}
+
+static int profi_release(struct inode *node, struct file *filp)
+{
+	struct profi_open_file *of = filp->private_data;
+	struct profi_priv *priv = of->priv;
+
+	kfree(of);
+	if (!atomic_dec_and_test(&priv->refcount))
+		return 0;
+	return profinet_disable(priv);
+}
+
+static long profi_ioctl(struct file *filp, unsigned int cmd,
+						unsigned long arg)
+{
+	struct profi_open_file *of = filp->private_data;
+	struct profi_priv *priv = of->priv;
+	void __user *argp = (void __user *)arg;
+	struct ProfinetConfig config;
+
+	if (_IOC_TYPE(cmd) != PROFINET_IOC_MAGIC)
+		return -EINVAL;
+	if (!(_IOC_DIR(cmd) & _IOC_WRITE))
+		return -EINVAL;
+	switch (cmd) {
+	case PROFINET_IOCSETCONFIG:
+		if (copy_from_user(&config, argp, sizeof(config)))
+			return -EFAULT;
+		return profinet_enable(priv, &config);
+	default:
+		break;
+	}
+	return -ENOTTY;
+}
+
+static ssize_t
+profi_read(struct file *filp, char __user *buf, size_t size,
+							loff_t *offset)
+{
+	struct profi_open_file *of = filp->private_data;
+	struct profi_priv *priv = of->priv;
+
+	return anybuss_read_output(priv->client, &of->event, buf, size,
+							offset);
+}
+
+static ssize_t
+profi_write(struct file *filp, const char __user *buf, size_t size,
+							loff_t *offset)
+{
+	struct profi_open_file *of = filp->private_data;
+	struct profi_priv *priv = of->priv;
+
+	return anybuss_write_input(priv->client, buf, size, offset);
+}
+
+static unsigned int profi_poll(struct file *filp, poll_table *wait)
+{
+	struct profi_open_file *of = filp->private_data;
+	struct profi_priv *priv = of->priv;
+
+	return anybuss_poll(priv->client, of->event, filp, wait);
+}
+
+static const struct file_operations fops = {
+	.open = profi_open,
+	.release = profi_release,
+	.read = profi_read,
+	.write = profi_write,
+	.unlocked_ioctl = profi_ioctl,
+	.poll = profi_poll,
+	.llseek = generic_file_llseek,
+	.owner = THIS_MODULE,
+};
+
+static DEFINE_IDA(profi_index_ida);
+
+static int profinet_probe(struct anybuss_client *client)
+{
+	struct profi_priv *priv;
+	struct device *dev = &client->dev;
+	int err;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+	atomic_set(&priv->refcount, 0);
+	mutex_init(&priv->enable_lock);
+	priv->client = client;
+	priv->misc.minor = MISC_DYNAMIC_MINOR;
+	priv->id = ida_simple_get(&profi_index_ida, 0, 0, GFP_KERNEL);
+	if (priv->id < 0)
+		return priv->id;
+	snprintf(priv->node_name, sizeof(priv->node_name), "profinet%d",
+				priv->id);
+	priv->misc.name = priv->node_name;
+	priv->misc.fops = &fops;
+	priv->misc.parent = client->dev.parent;
+	err = misc_register(&priv->misc);
+	if (err < 0) {
+		dev_err(dev, "could not register device (%d)", err);
+		goto err_ida;
+	}
+	priv->dev = priv->misc.this_device;
+	dev_set_drvdata(priv->dev, priv);
+	err = sysfs_create_group(&priv->dev->kobj, &ctrl_group);
+	if (err < 0) {
+		dev_err(dev, "could not create sysfs group (%d)", err);
+		goto err_register;
+	}
+	dev_info(priv->dev, "detected on %s", dev_name(&client->dev));
+	anybuss_set_drvdata(client, priv);
+	return 0;
+err_register:
+	misc_deregister(&priv->misc);
+err_ida:
+	ida_simple_remove(&profi_index_ida, priv->id);
+	return err;
+}
+
+static int profinet_remove(struct anybuss_client *client)
+{
+	struct profi_priv *priv = anybuss_get_drvdata(client);
+
+	sysfs_remove_group(&priv->dev->kobj, &ctrl_group);
+	misc_deregister(&priv->misc);
+	ida_simple_remove(&profi_index_ida, priv->id);
+	return 0;
+}
+
+static struct anybuss_client_driver profinet_driver = {
+	.probe = profinet_probe,
+	.remove = profinet_remove,
+	.driver		= {
+		.name   = "hms-profinet",
+		.owner	= THIS_MODULE,
+	},
+	.fieldbus_type = 0x0089,
+};
+
+static int __init profinet_init(void)
+{
+	return anybuss_client_driver_register(&profinet_driver);
+}
+module_init(profinet_init);
+
+static void __exit profinet_exit(void)
+{
+	return anybuss_client_driver_unregister(&profinet_driver);
+}
+module_exit(profinet_exit);
+
+MODULE_AUTHOR("Sven Van Asbroeck <svendev@arcx.com>");
+MODULE_DESCRIPTION("HMS Profinet IRT Driver (Anybus-S)");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/hms-common.h b/include/uapi/linux/hms-common.h
new file mode 100644
index 000000000000..4b69963a3863
--- /dev/null
+++ b/include/uapi/linux/hms-common.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018 Archronix Corp. All Rights Reserved.
+ *
+ */
+
+#ifndef _UAPILINUX_HMSCOMMON_H_
+#define _UAPILINUX_HMSCOMMON_H_
+
+#define HMS_SMA_CLEAR		0
+#define HMS_SMA_FREEZE		1
+#define HMS_SMA_SET		2
+
+#endif /* _UAPILINUX_HMSCOMMON_H_ */
diff --git a/include/uapi/linux/hms-profinet.h b/include/uapi/linux/hms-profinet.h
new file mode 100644
index 000000000000..4ae5eab8ab43
--- /dev/null
+++ b/include/uapi/linux/hms-profinet.h
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018 Archronix Corp. All Rights Reserved.
+ *
+ */
+
+#ifndef _UAPILINUX_PROFINET_H_
+#define _UAPILINUX_PROFINET_H_
+
+#include <asm/types.h>
+#include <linux/hms-common.h>
+
+#define PROFI_CFG_STRLEN	64
+
+struct ProfinetConfig {
+	struct {
+		/* addresses IN NETWORK ORDER! */
+		__u32 ip_addr;
+		__u32 subnet_msk;
+		__u32 gateway_addr;
+		__u8  is_valid:1;
+	} eth;
+	struct {
+		__u16 vendorid, deviceid;
+		__u8  is_valid:1;
+	} dev_id;
+	struct {
+		char name[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} station_name;
+	struct {
+		char name[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} station_type;
+	struct {
+		__u8 addr[6];
+		__u8 is_valid:1;
+	} mac_addr;
+	struct {
+		char hostname[PROFI_CFG_STRLEN];
+		char domainname[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} host_domain;
+	struct {
+		__u8 enable:1;
+		__u8 is_valid:1;
+	} hicp;
+	struct {
+		__u8 enable:1;
+		__u8 is_valid:1;
+	} web_server;
+	struct {
+		__u8 disable:1;
+	} ftp_server;
+	struct {
+		__u8 enable:1;
+	} global_admin_mode;
+	struct {
+		__u8 disable:1;
+	} vfs;
+	struct {
+		/* one of HMS_SMA_CLEAR/FREEZE/SET */
+		int action;
+		__u8 is_valid:1;
+	} stop_mode;
+	struct {
+		char description[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} snmp_system_descr;
+	struct {
+		char description[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} snmp_iface_descr;
+	struct {
+		char description[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} mib2_system_descr;
+	struct {
+		char contact[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} mib2_system_contact;
+	struct {
+		char location[PROFI_CFG_STRLEN];
+		__u8 is_valid:1;
+	} mib2_system_location;
+	/* use non-volatile defaults for any properties not specified.
+	 * when in doubt, keep this OFF.
+	 */
+	__u8 use_nv_defaults:1;
+};
+
+#define PROFINET_IOC_MAGIC 'l'
+
+/*
+ * Configures profinet according to the ProfinetConfig structure, and
+ * switches the card on if it was previously off.
+ */
+#define PROFINET_IOCSETCONFIG   _IOW(PROFINET_IOC_MAGIC, 1,\
+						struct ProfinetConfig)
+
+#endif /* _UAPILINUX_PROFINET_H_ */
-- 
2.17.1

Re: [PATCH anybus v1 4/4] misc: support HMS Profinet IRT industrial controller.

[Randy Dunlap]

Hi,

On 10/24/18 7:24 AM, Sven Van Asbroeck wrote:
> The Anybus-S PROFINET IRT communication module provides instant integration
> to any Ethernet based LAN via SMTP, FTP, HTTP as well as PROFINET and
> Modbus-TCP. Additional protocols can be implemented on top of TCP/IP
> or UDP using the transparent socket interface.
> 
> Official documentation:
> https://www.anybus.com/docs/librariesprovider7/default-document-library
> /manuals-design-guides/hms-hmsi-168-52.pdf
> 
> This implementation is an Anybus-S client driver, designed to be
> instantiated by the Anybus-S bus driver when it discovers the Profinet
> card.
> 
> If loaded successfully, the driver creates a /dev/profinet%d devnode,
> and a /sys/class/misc/profinet%d sysfs subdir:
> - the card can be configured with a single, atomic ioctl on the devnode;
> - the card's internal dpram is accessed by calling read/write/seek
>     on the devnode.
> - the card's "fieldbus specific area" properties can be accessed via
>     the sysfs dir.
> 
> Signed-off-by: Sven Van Asbroeck <svendev@arcx.com>
> ---
>  drivers/misc/Kconfig              |  11 +
>  drivers/misc/Makefile             |   1 +
>  drivers/misc/hms-profinet.c       | 747 ++++++++++++++++++++++++++++++
>  include/uapi/linux/hms-common.h   |  14 +
>  include/uapi/linux/hms-profinet.h | 101 ++++
>  5 files changed, 874 insertions(+)
>  create mode 100644 drivers/misc/hms-profinet.c
>  create mode 100644 include/uapi/linux/hms-common.h
>  create mode 100644 include/uapi/linux/hms-profinet.h
> 
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index 3726eacdf65d..377fea2e3003 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -406,6 +406,17 @@ config SPEAR13XX_PCIE_GADGET
>  	 entry will be created for that controller. User can use these
>  	 sysfs node to configure PCIe EP as per his requirements.
>  
> +config HMS_PROFINET
> +	tristate "HMS Profinet IRT Controller (Anybus-S)"
> +	select HMS_ANYBUSS_HOST
> +	default n

Please drop the "default n".

> +	help
> +	 If you say yes here you get support for the HMS Industrial
> +	 Networks Profinet IRT Controller.
> +	 This driver can also be built as a module. If so, the module
> +	 will be called hms-profinet.
> +	 If unsure, say N.
> +
>  config VMWARE_BALLOON
>  	tristate "VMware Balloon Driver"
>  	depends on VMWARE_VMCI && X86 && HYPERVISOR_GUEST

> diff --git a/drivers/misc/hms-profinet.c b/drivers/misc/hms-profinet.c
> new file mode 100644
> index 000000000000..7338a49cbddd
> --- /dev/null
> +++ b/drivers/misc/hms-profinet.c

Please check multi-line comment style in this source file.



> diff --git a/include/uapi/linux/hms-profinet.h b/include/uapi/linux/hms-profinet.h
> new file mode 100644
> index 000000000000..4ae5eab8ab43
> --- /dev/null
> +++ b/include/uapi/linux/hms-profinet.h
> @@ -0,0 +1,101 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright 2018 Archronix Corp. All Rights Reserved.
> + *
> + */
> +
> +#ifndef _UAPILINUX_PROFINET_H_
> +#define _UAPILINUX_PROFINET_H_
> +
> +#include <asm/types.h>
> +#include <linux/hms-common.h>
> +
> +#define PROFI_CFG_STRLEN	64
> +
> +struct ProfinetConfig {
> +	struct {
> +		/* addresses IN NETWORK ORDER! */
> +		__u32 ip_addr;
> +		__u32 subnet_msk;
> +		__u32 gateway_addr;
> +		__u8  is_valid:1;
> +	} eth;
> +	struct {
> +		__u16 vendorid, deviceid;
> +		__u8  is_valid:1;
> +	} dev_id;
> +	struct {
> +		char name[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} station_name;
> +	struct {
> +		char name[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} station_type;
> +	struct {
> +		__u8 addr[6];
> +		__u8 is_valid:1;
> +	} mac_addr;
> +	struct {
> +		char hostname[PROFI_CFG_STRLEN];
> +		char domainname[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} host_domain;
> +	struct {
> +		__u8 enable:1;
> +		__u8 is_valid:1;
> +	} hicp;
> +	struct {
> +		__u8 enable:1;
> +		__u8 is_valid:1;
> +	} web_server;
> +	struct {
> +		__u8 disable:1;
> +	} ftp_server;
> +	struct {
> +		__u8 enable:1;
> +	} global_admin_mode;
> +	struct {
> +		__u8 disable:1;
> +	} vfs;
> +	struct {
> +		/* one of HMS_SMA_CLEAR/FREEZE/SET */
> +		int action;
> +		__u8 is_valid:1;
> +	} stop_mode;
> +	struct {
> +		char description[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} snmp_system_descr;
> +	struct {
> +		char description[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} snmp_iface_descr;
> +	struct {
> +		char description[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} mib2_system_descr;
> +	struct {
> +		char contact[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} mib2_system_contact;
> +	struct {
> +		char location[PROFI_CFG_STRLEN];
> +		__u8 is_valid:1;
> +	} mib2_system_location;
> +	/* use non-volatile defaults for any properties not specified.
> +	 * when in doubt, keep this OFF.
> +	 */
> +	__u8 use_nv_defaults:1;
> +};
> +
> +#define PROFINET_IOC_MAGIC 'l'
> +
> +/*
> + * Configures profinet according to the ProfinetConfig structure, and
> + * switches the card on if it was previously off.
> + */
> +#define PROFINET_IOCSETCONFIG   _IOW(PROFINET_IOC_MAGIC, 1,\
> +						struct ProfinetConfig)

ioctl magic numbers should be added to
Documentation/ioctl/ioctl-number.txt, please.

> +
> +#endif /* _UAPILINUX_PROFINET_H_ */
> 


-- 
~Randy

Re: [PATCH anybus v1 0/4] Support HMS Profinet Card over Anybus

[Andy Shevchenko]

On Wed, Oct 24, 2018 at 10:24:52AM -0400, Sven Van Asbroeck wrote:
> This patch set adds support for the HMS Industrial Networks AB Profinet card.
> 
> Profinet is an industry technical standard for data communication over
> Industrial Ethernet, designed for collecting data from, and controlling,
> equipment in industrial systems, with a particular strength in delivering data
> under tight time constraints (on the order of 1ms or less).
> 
> The profinet card itself is connected to the system via an industrial bus
> called 'anybus'.
> 
> I have followed the bus driver/client driver pattern, and created an anybus
> bus driver, plus a client driver for the profinet card.
> 
> In case this patch set gets (eventually) accepted, drivers for other anybus
> client cards may follow: flnet, cc-link, ...
> 
> The anybus slot on the host is located on an 'anybus bridge', which is
> custom h/w designed by Arcx. Its driver is modeled as an mfd, which
> instantiates two anybus slots.

I highly recommend to look at my recent (for few month?) reviews -- they are
almost repeating each other.

Also check what we have under lib/ (hint: read linux/kernel.h for inline and
exported function helpers).

I might look at the patches later on if I would have some spare time (I
actually don't know why I'm in Cc list here).

> 
> v1:
> 	first shot
> 
> Sven Van Asbroeck (4):
>   mfd: support the Arcx anybus bridge.
>   dt-bindings: anybus-bridge: document devicetree binding.
>   bus: support HMS Anybus-S bus.
>   misc: support HMS Profinet IRT industrial controller.
> 
>  .../bindings/mfd/arcx,anybus-bridge.txt       |   37 +
>  .../devicetree/bindings/vendor-prefixes.txt   |    1 +
>  drivers/bus/Kconfig                           |   11 +
>  drivers/bus/Makefile                          |    1 +
>  drivers/bus/anybuss-host.c                    | 1301 +++++++++++++++++
>  drivers/mfd/Kconfig                           |   11 +
>  drivers/mfd/Makefile                          |    1 +
>  drivers/mfd/anybus-bridge.c                   |  441 ++++++
>  drivers/misc/Kconfig                          |   11 +
>  drivers/misc/Makefile                         |    1 +
>  drivers/misc/hms-profinet.c                   |  747 ++++++++++
>  include/linux/anybuss-client.h                |  100 ++
>  include/linux/anybuss-host.h                  |   28 +
>  include/uapi/linux/hms-common.h               |   14 +
>  include/uapi/linux/hms-profinet.h             |  101 ++
>  15 files changed, 2806 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/arcx,anybus-bridge.txt
>  create mode 100644 drivers/bus/anybuss-host.c
>  create mode 100644 drivers/mfd/anybus-bridge.c
>  create mode 100644 drivers/misc/hms-profinet.c
>  create mode 100644 include/linux/anybuss-client.h
>  create mode 100644 include/linux/anybuss-host.h
>  create mode 100644 include/uapi/linux/hms-common.h
>  create mode 100644 include/uapi/linux/hms-profinet.h
> 
> -- 
> 2.17.1
> 

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH anybus v1 0/4] Support HMS Profinet Card over Anybus

[Sven Van Asbroeck]

Thanks for your feedback, I appreciate it !

On Thu, Oct 25, 2018 at 5:19 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:

>
> I highly recommend to look at my recent (for few month?) reviews -- they are
> almost repeating each other.
>
> Also check what we have under lib/ (hint: read linux/kernel.h for inline and
> exported function helpers).

Would you be able, in a few words, to describe which of your reviews I
should concentrate on? Or which /lib files are of interest?
I've looked through your reviews and in the /lib directory, but other
than refcount_t, nothing jumped out at me.

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[thesven73]

Hi Rob, thank you so much for taking a look at this patch !

>> +This chip communicates with the SoC over the WEIM bus. It is
>> +expected that its Device Tree node is specified as the child of a node
>> +corresponding to the WEIM bus used for communication.
>
>By WEIM you are referring to i.MX external parallel bus? Presumably this 
>can work on any parallel bus, not just i.MX.

That's right, in theory this hardware could work with any parallel bus, if
timed correctly. The driver also has no code dependencies on the WEIM driver.
You'll only find it in the field on top of the i.MX's WEIM bus, however.

Do you think it would be 'nicer' to drop references to i.MX and WEIM? Can do.

>> +  - compatible : The following chip-specific string:
>> +        "arcx,anybus-bridge"
>
>No version or part number?

We have id and capability registers in the chip for that. This driver is
generic, both forwards and backwards compatible. Is it ok to leave out
version/part number in this case?

The rest of your feedback will go into v2. Thanks :)

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[thesven73]

Hi Linus, thank you for the patch review !!

>> +  - pwms : the pwm connected to the bridge's 'pwm input'.
>
> That is really unintuitive and needs a detailed explanation. What
> is a bridge doing with a PWM? Is it 100% certain this is a PWM,
> it's not just a .... clock? A pwm is a pule WIDTH modulator and
> I can't for my life understand why a bus bridge needs a signal
> with variable pulse width, but surprise me! :D

You are 100% correct, this is a clock !
The hardware designers attached the bridge's clock input to an iMX pwm output,
and instructed us to provide a clock with 50% duty cycle and a certain freq.

The only way I know to activate a pwm is to connect it to a driver in the fdt,
then inside the driver enable the pwm, like so:

+       /* PWM */
+       pwm = devm_pwm_get(dev, NULL);
+       if (IS_ERR(pwm)) {
+               dev_err(dev, "pwm not found\n");
+               return -EINVAL;
+       }
+       pwm_get_args(pwm, &pargs);
+       period = pargs.period;
+       err = pwm_config(pwm, period/2, period);
+       if (err)
+               return err;
+       err = pwm_enable(pwm);
+       if (err)
+               return err;

This is why the bridge driver has a dependency on a pwm.
If the pwm could be enabled individually, I could drop this dependency.
Can you think of a way?

>> +               fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
>> +                               0x00000000 0xa0000240 0x00000000>;
>
> Is it just a copy/paste from
> Documentation/devicetree/bindings/bus/imx-weim.txt
> leftover?

No. We attach the bridge to the i.MX WEIM bus. Every fdt WEIM child node
requires a fsl,weim-cs-timing property, which provides the bus timing for
that particular chip select. It's the weim driver that requires this,
I'm only following its instructions.

Should I just leave this out in the example? In theory, the bridge can be
connected to any parallel bus, so fsl,weim-cs-timing is Too Much Information
for the example?

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[David Lechner]

On 10/25/2018 08:55 AM, thesven73@gmail.com wrote:
> Hi Linus, thank you for the patch review !!
> 
>>> +  - pwms : the pwm connected to the bridge's 'pwm input'.
>>
>> That is really unintuitive and needs a detailed explanation. What
>> is a bridge doing with a PWM? Is it 100% certain this is a PWM,
>> it's not just a .... clock? A pwm is a pule WIDTH modulator and
>> I can't for my life understand why a bus bridge needs a signal
>> with variable pulse width, but surprise me! :D
> 
> You are 100% correct, this is a clock !
> The hardware designers attached the bridge's clock input to an iMX pwm output,
> and instructed us to provide a clock with 50% duty cycle and a certain freq.
> 
> The only way I know to activate a pwm is to connect it to a driver in the fdt,
> then inside the driver enable the pwm, like so:
> 
> +       /* PWM */
> +       pwm = devm_pwm_get(dev, NULL);
> +       if (IS_ERR(pwm)) {
> +               dev_err(dev, "pwm not found\n");
> +               return -EINVAL;
> +       }
> +       pwm_get_args(pwm, &pargs);
> +       period = pargs.period;
> +       err = pwm_config(pwm, period/2, period);
> +       if (err)
> +               return err;
> +       err = pwm_enable(pwm);
> +       if (err)
> +               return err;
> 
> This is why the bridge driver has a dependency on a pwm.
> If the pwm could be enabled individually, I could drop this dependency.
> Can you think of a way?


How about using the pwm-clock device tree binding to turn the PWM into
a clock?

Documentation/devicetree/bindings/clock/pwm-clock.txt

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Linus Walleij]

On Thu, Oct 25, 2018 at 3:55 PM <thesven73@gmail.com> wrote:

> >> +               fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
> >> +                               0x00000000 0xa0000240 0x00000000>;
> >
> > Is it just a copy/paste from
> > Documentation/devicetree/bindings/bus/imx-weim.txt
> > leftover?
>
> No. We attach the bridge to the i.MX WEIM bus. Every fdt WEIM child node
> requires a fsl,weim-cs-timing property, which provides the bus timing for
> that particular chip select. It's the weim driver that requires this,
> I'm only following its instructions.
>
> Should I just leave this out in the example? In theory, the bridge can be
> connected to any parallel bus, so fsl,weim-cs-timing is Too Much Information
> for the example?

No it's fine, I understand it now.

Whay you can do is write before the example that this example node
is using the WEIM bindings and reference that binding document.

Yours,
Linus Walleij

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[thesven73]

>> This is why the bridge driver has a dependency on a pwm.
>> If the pwm could be enabled individually, I could drop this dependency.
>> Can you think of a way?
>
> How about using the pwm-clock device tree binding to turn the PWM into
> a clock?
> Documentation/devicetree/bindings/clock/pwm-clock.txt

Looks like a winner. Thanks !!

Re: [PATCH anybus v1 2/4] dt-bindings: anybus-bridge: document devicetree binding.

[Lee Jones]

On Thu, 25 Oct 2018, thesven73@gmail.com wrote:

> >> This is why the bridge driver has a dependency on a pwm.
> >> If the pwm could be enabled individually, I could drop this dependency.
> >> Can you think of a way?
> >
> > How about using the pwm-clock device tree binding to turn the PWM into
> > a clock?
> > Documentation/devicetree/bindings/clock/pwm-clock.txt
> 
> Looks like a winner. Thanks !!

Could you fix your mailed to reply to mails 'threaded' please?

Your mails are now spread far and wide across my Inbox.

Thanks.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
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