Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Greg KH]

On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> Introduce new Mellanox platform driver to allow access to Mellanox
> programmable device register space trough sysfs interface.
> The driver purpose is to provide sysfs interface for user space for the
> registers essential for system control and monitoring.
> The sets of registers for sysfs access are supposed to be defined per
> system type bases and include the registers related to system resets
> operation, system reset causes monitoring and some kinds of mux selection.
> 
> Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> ---
> v1->v2:
>  Changed added by Vadim:
>  - Change ---help--- to help in Kconfig, according to new requirements;
> v2->v3:
>  Comments pointed out by Darren:
>  - Remove conditional assignment per attribute mode type, because mode
>    will guard against not permitted access.
>    Verified by Vadim.
> ---
>  drivers/platform/mellanox/Kconfig     |  11 ++
>  drivers/platform/mellanox/Makefile    |   1 +
>  drivers/platform/mellanox/mlxreg-io.c | 203 ++++++++++++++++++++++++++++++++++
>  3 files changed, 215 insertions(+)
>  create mode 100644 drivers/platform/mellanox/mlxreg-io.c
> 
> diff --git a/drivers/platform/mellanox/Kconfig b/drivers/platform/mellanox/Kconfig
> index 591bccd..ddfae9fc 100644
> --- a/drivers/platform/mellanox/Kconfig
> +++ b/drivers/platform/mellanox/Kconfig
> @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
>  	  This driver handles hot-plug events for the power suppliers, power
>  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
>  
> +config MLXREG_IO
> +	tristate "Mellanox platform register access driver support"
> +	depends on REGMAP
> +	depends on HWMON
> +	help
> +	  This driver allows access to Mellanox programmable device register
> +	  space trough sysfs interface. The sets of registers for sysfs access
> +	  are defined per system type bases and includes the registers related
> +	  to system resets operation, system reset causes monitoring and some
> +	  kinds of mux selection.

No Documentation/ABI/ entries for these new sysfs files?  Not good :(

greg k-h

RE: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Vadim Pasternak]

> -----Original Message-----
> From: Greg KH [mailto:gregkh@linuxfoundation.org]
> Sent: Sunday, May 27, 2018 6:14 PM
> To: Vadim Pasternak <vadimp@mellanox.com>
> Cc: dvhart@infradead.org; andy.shevchenko@gmail.com; linux-
> kernel@vger.kernel.org; platform-driver-x86@vger.kernel.org; jiri@resnulli.us;
> Michael Shych <michaelsh@mellanox.com>; ivecera@redhat.com
> Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox
> register access driver
> 
> On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> > Introduce new Mellanox platform driver to allow access to Mellanox
> > programmable device register space trough sysfs interface.
> > The driver purpose is to provide sysfs interface for user space for
> > the registers essential for system control and monitoring.
> > The sets of registers for sysfs access are supposed to be defined per
> > system type bases and include the registers related to system resets
> > operation, system reset causes monitoring and some kinds of mux selection.
> >
> > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> > ---
> > v1->v2:
> >  Changed added by Vadim:
> >  - Change ---help--- to help in Kconfig, according to new
> > requirements;
> > v2->v3:
> >  Comments pointed out by Darren:
> >  - Remove conditional assignment per attribute mode type, because mode
> >    will guard against not permitted access.
> >    Verified by Vadim.
> > ---
> >  drivers/platform/mellanox/Kconfig     |  11 ++
> >  drivers/platform/mellanox/Makefile    |   1 +
> >  drivers/platform/mellanox/mlxreg-io.c | 203
> > ++++++++++++++++++++++++++++++++++
> >  3 files changed, 215 insertions(+)
> >  create mode 100644 drivers/platform/mellanox/mlxreg-io.c
> >
> > diff --git a/drivers/platform/mellanox/Kconfig
> > b/drivers/platform/mellanox/Kconfig
> > index 591bccd..ddfae9fc 100644
> > --- a/drivers/platform/mellanox/Kconfig
> > +++ b/drivers/platform/mellanox/Kconfig
> > @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
> >  	  This driver handles hot-plug events for the power suppliers, power
> >  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
> >
> > +config MLXREG_IO
> > +	tristate "Mellanox platform register access driver support"
> > +	depends on REGMAP
> > +	depends on HWMON
> > +	help
> > +	  This driver allows access to Mellanox programmable device register
> > +	  space trough sysfs interface. The sets of registers for sysfs access
> > +	  are defined per system type bases and includes the registers related
> > +	  to system resets operation, system reset causes monitoring and some
> > +	  kinds of mux selection.
> 
> No Documentation/ABI/ entries for these new sysfs files?  Not good :(
> 

Thanks Greg for your comment.

Should I call doc file like:
Documentation/ABI/stable/sysfs-driver-mlxreg-io
?

> greg k-h

Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Greg KH]

On Sun, May 27, 2018 at 03:22:06PM +0000, Vadim Pasternak wrote:
> 
> 
> > -----Original Message-----
> > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > Sent: Sunday, May 27, 2018 6:14 PM
> > To: Vadim Pasternak <vadimp@mellanox.com>
> > Cc: dvhart@infradead.org; andy.shevchenko@gmail.com; linux-
> > kernel@vger.kernel.org; platform-driver-x86@vger.kernel.org; jiri@resnulli.us;
> > Michael Shych <michaelsh@mellanox.com>; ivecera@redhat.com
> > Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox
> > register access driver
> > 
> > On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> > > Introduce new Mellanox platform driver to allow access to Mellanox
> > > programmable device register space trough sysfs interface.
> > > The driver purpose is to provide sysfs interface for user space for
> > > the registers essential for system control and monitoring.
> > > The sets of registers for sysfs access are supposed to be defined per
> > > system type bases and include the registers related to system resets
> > > operation, system reset causes monitoring and some kinds of mux selection.
> > >
> > > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> > > ---
> > > v1->v2:
> > >  Changed added by Vadim:
> > >  - Change ---help--- to help in Kconfig, according to new
> > > requirements;
> > > v2->v3:
> > >  Comments pointed out by Darren:
> > >  - Remove conditional assignment per attribute mode type, because mode
> > >    will guard against not permitted access.
> > >    Verified by Vadim.
> > > ---
> > >  drivers/platform/mellanox/Kconfig     |  11 ++
> > >  drivers/platform/mellanox/Makefile    |   1 +
> > >  drivers/platform/mellanox/mlxreg-io.c | 203
> > > ++++++++++++++++++++++++++++++++++
> > >  3 files changed, 215 insertions(+)
> > >  create mode 100644 drivers/platform/mellanox/mlxreg-io.c
> > >
> > > diff --git a/drivers/platform/mellanox/Kconfig
> > > b/drivers/platform/mellanox/Kconfig
> > > index 591bccd..ddfae9fc 100644
> > > --- a/drivers/platform/mellanox/Kconfig
> > > +++ b/drivers/platform/mellanox/Kconfig
> > > @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
> > >  	  This driver handles hot-plug events for the power suppliers, power
> > >  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
> > >
> > > +config MLXREG_IO
> > > +	tristate "Mellanox platform register access driver support"
> > > +	depends on REGMAP
> > > +	depends on HWMON
> > > +	help
> > > +	  This driver allows access to Mellanox programmable device register
> > > +	  space trough sysfs interface. The sets of registers for sysfs access
> > > +	  are defined per system type bases and includes the registers related
> > > +	  to system resets operation, system reset causes monitoring and some
> > > +	  kinds of mux selection.
> > 
> > No Documentation/ABI/ entries for these new sysfs files?  Not good :(
> > 
> 
> Thanks Greg for your comment.
> 
> Should I call doc file like:
> Documentation/ABI/stable/sysfs-driver-mlxreg-io
> ?

What ever matches the naming scheme for the driver, yes.

thanks,

greg k-h

[PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Vadim Pasternak]

Introduce new Mellanox platform driver to allow access to Mellanox
programmable device register space trough sysfs interface.
The driver purpose is to provide sysfs interface for user space for the
registers essential for system control and monitoring.
The sets of registers for sysfs access are supposed to be defined per
system type bases and include the registers related to system resets
operation, system reset causes monitoring and some kinds of mux selection.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
---
v1->v2:
 Changed added by Vadim:
 - Change ---help--- to help in Kconfig, according to new requirements;
v2->v3:
 Comments pointed out by Darren:
 - Remove conditional assignment per attribute mode type, because mode
   will guard against not permitted access.
   Verified by Vadim.
---
 drivers/platform/mellanox/Kconfig     |  11 ++
 drivers/platform/mellanox/Makefile    |   1 +
 drivers/platform/mellanox/mlxreg-io.c | 203 ++++++++++++++++++++++++++++++++++
 3 files changed, 215 insertions(+)
 create mode 100644 drivers/platform/mellanox/mlxreg-io.c

diff --git a/drivers/platform/mellanox/Kconfig b/drivers/platform/mellanox/Kconfig
index 591bccd..ddfae9fc 100644
--- a/drivers/platform/mellanox/Kconfig
+++ b/drivers/platform/mellanox/Kconfig
@@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
 	  This driver handles hot-plug events for the power suppliers, power
 	  cables and fans on the wide range Mellanox IB and Ethernet systems.
 
+config MLXREG_IO
+	tristate "Mellanox platform register access driver support"
+	depends on REGMAP
+	depends on HWMON
+	help
+	  This driver allows access to Mellanox programmable device register
+	  space trough sysfs interface. The sets of registers for sysfs access
+	  are defined per system type bases and includes the registers related
+	  to system resets operation, system reset causes monitoring and some
+	  kinds of mux selection.
+
 endif # MELLANOX_PLATFORM
diff --git a/drivers/platform/mellanox/Makefile b/drivers/platform/mellanox/Makefile
index 7c8385e..57074d9c 100644
--- a/drivers/platform/mellanox/Makefile
+++ b/drivers/platform/mellanox/Makefile
@@ -4,3 +4,4 @@
 # Mellanox Platform-Specific Drivers
 #
 obj-$(CONFIG_MLXREG_HOTPLUG)	+= mlxreg-hotplug.o
+obj-$(CONFIG_MLXREG_IO) += mlxreg-io.o
diff --git a/drivers/platform/mellanox/mlxreg-io.c b/drivers/platform/mellanox/mlxreg-io.c
new file mode 100644
index 0000000..b85452f
--- /dev/null
+++ b/drivers/platform/mellanox/mlxreg-io.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Mellanox register access driver
+ *
+ * Copyright (C) 2018 Mellanox Technologies
+ * Copyright (C) 2018 Vadim Pasternak <vadimp@mellanox.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_data/mlxreg.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* Attribute parameters. */
+#define MLXREG_IO_ATT_SIZE	10
+#define MLXREG_IO_ATT_NUM	48
+
+/**
+ * struct mlxreg_io_priv_data - driver's private data:
+ *
+ * @pdev: platform device;
+ * @pdata: platform data;
+ * @hwmon: hwmon device;
+ * @mlxreg_io_attr: sysfs attributes array;
+ * @mlxreg_io_dev_attr: sysfs sensor device attribute array;
+ * @group: sysfs attribute group;
+ * @groups: list of sysfs attribute group for hwmon registration;
+ */
+struct mlxreg_io_priv_data {
+	struct platform_device *pdev;
+	struct mlxreg_core_platform_data *pdata;
+	struct device *hwmon;
+	struct attribute *mlxreg_io_attr[MLXREG_IO_ATT_NUM + 1];
+	struct sensor_device_attribute mlxreg_io_dev_attr[MLXREG_IO_ATT_NUM];
+	struct attribute_group group;
+	const struct attribute_group *groups[2];
+};
+
+static ssize_t
+mlxreg_io_attr_show(struct device *dev, struct device_attribute *attr,
+		    char *buf)
+{
+	struct mlxreg_io_priv_data *priv = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(attr)->index;
+	struct mlxreg_core_data *data = priv->pdata->data + index;
+	u32 regval = 0;
+	int ret;
+
+	ret = regmap_read(priv->pdata->regmap, data->reg, &regval);
+	if (ret)
+		goto access_error;
+
+	if (!data->bit)
+		regval = !!(regval & ~data->mask);
+
+	return sprintf(buf, "%u\n", regval);
+
+access_error:
+	return ret;
+}
+
+static ssize_t
+mlxreg_io_attr_store(struct device *dev, struct device_attribute *attr,
+		     const char *buf, size_t len)
+{
+	struct mlxreg_io_priv_data *priv = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(attr)->index;
+	struct mlxreg_core_data *data = priv->pdata->data + index;
+	u32 val, regval;
+	int ret;
+
+	ret = kstrtou32(buf, MLXREG_IO_ATT_SIZE, &val);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(priv->pdata->regmap, data->reg, &regval);
+	if (ret)
+		goto access_error;
+
+	regval &= data->mask;
+
+	val = !!val;
+	if (val)
+		regval |= ~data->mask;
+	else
+		regval &= data->mask;
+
+	ret = regmap_write(priv->pdata->regmap, data->reg, regval);
+	if (ret)
+		goto access_error;
+
+	return len;
+
+access_error:
+	dev_err(&priv->pdev->dev, "Bus access error\n");
+	return ret;
+}
+
+static struct device_attribute mlxreg_io_devattr_rw = {
+	.show	= mlxreg_io_attr_show,
+	.store	= mlxreg_io_attr_store,
+};
+
+static int mlxreg_io_attr_init(struct mlxreg_io_priv_data *priv)
+{
+	int i;
+
+	priv->group.attrs = devm_kzalloc(&priv->pdev->dev,
+					 priv->pdata->counter *
+					 sizeof(struct attribute *),
+					 GFP_KERNEL);
+	if (!priv->group.attrs)
+		return -ENOMEM;
+
+	for (i = 0; i < priv->pdata->counter; i++) {
+		priv->mlxreg_io_attr[i] =
+				&priv->mlxreg_io_dev_attr[i].dev_attr.attr;
+		memcpy(&priv->mlxreg_io_dev_attr[i].dev_attr,
+		       &mlxreg_io_devattr_rw, sizeof(struct device_attribute));
+
+		/* Set attribute name as a label. */
+		priv->mlxreg_io_attr[i]->name =
+				devm_kasprintf(&priv->pdev->dev, GFP_KERNEL,
+					       priv->pdata->data[i].label);
+
+		if (!priv->mlxreg_io_attr[i]->name) {
+			dev_err(&priv->pdev->dev, "Memory allocation failed for sysfs attribute %d.\n",
+				i + 1);
+			return -ENOMEM;
+		}
+
+		priv->mlxreg_io_dev_attr[i].dev_attr.attr.mode =
+						priv->pdata->data[i].mode;
+		priv->mlxreg_io_dev_attr[i].dev_attr.attr.name =
+					priv->mlxreg_io_attr[i]->name;
+		priv->mlxreg_io_dev_attr[i].index = i;
+		sysfs_attr_init(&priv->mlxreg_io_dev_attr[i].dev_attr.attr);
+	}
+
+	priv->group.attrs = priv->mlxreg_io_attr;
+	priv->groups[0] = &priv->group;
+	priv->groups[1] = NULL;
+
+	return 0;
+}
+
+static int mlxreg_io_probe(struct platform_device *pdev)
+{
+	struct mlxreg_io_priv_data *priv;
+	int err;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->pdata = dev_get_platdata(&pdev->dev);
+	if (!priv->pdata) {
+		dev_err(&pdev->dev, "Failed to get platform data.\n");
+		return -EINVAL;
+	}
+
+	priv->pdev = pdev;
+
+	err = mlxreg_io_attr_init(priv);
+	if (err) {
+		dev_err(&priv->pdev->dev, "Failed to allocate attributes: %d\n",
+			err);
+		return err;
+	}
+
+	priv->hwmon = devm_hwmon_device_register_with_groups(&pdev->dev,
+							     "mlxreg_io",
+							      priv,
+							      priv->groups);
+	if (IS_ERR(priv->hwmon)) {
+		dev_err(&pdev->dev, "Failed to register hwmon device %ld\n",
+			PTR_ERR(priv->hwmon));
+		return PTR_ERR(priv->hwmon);
+	}
+
+	dev_set_drvdata(&pdev->dev, priv);
+
+	return 0;
+}
+
+static struct platform_driver mlxreg_io_driver = {
+	.driver = {
+	    .name = "mlxreg-io",
+	},
+	.probe = mlxreg_io_probe,
+};
+
+module_platform_driver(mlxreg_io_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
+MODULE_DESCRIPTION("Mellanox regmap I/O access driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mlxreg-io");
-- 
2.1.4

[PATCH v3 7/7] platform/x86: mlx-platform: Add mlxreg-io platform driver activation

[Vadim Pasternak]

Add mlxreg-io platform driver activation. Access driver uses the same
regmap infrastructure as others Mellanox platform drivers.
Specific registers description for default platform data configuration are
added to mlx-platform. There are the registers for resets control, reset
causes monitoring, programmable devices version reading and mux select
control. This platform data is passed to mlxreg-io driver. Also some
default values for the register are set at initialization time through
the regmap infrastructure, which are necessary for moving write protection
from the general purpose registers, which are used by mlxreg-io for
write access.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
---
 drivers/platform/x86/mlx-platform.c | 159 +++++++++++++++++++++++++++++++++++-
 1 file changed, 157 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/mlx-platform.c b/drivers/platform/x86/mlx-platform.c
index a0fd9aa..87ddd3a 100644
--- a/drivers/platform/x86/mlx-platform.c
+++ b/drivers/platform/x86/mlx-platform.c
@@ -47,11 +47,18 @@
 /* LPC bus IO offsets */
 #define MLXPLAT_CPLD_LPC_I2C_BASE_ADRR		0x2000
 #define MLXPLAT_CPLD_LPC_REG_BASE_ADRR		0x2500
+#define MLXPLAT_CPLD_LPC_REG_CPLD1_VER_OFFSET	0x00
+#define MLXPLAT_CPLD_LPC_REG_CPLD2_VER_OFFSET	0x01
+#define MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET	0x1d
 #define MLXPLAT_CPLD_LPC_REG_LED1_OFFSET	0x20
 #define MLXPLAT_CPLD_LPC_REG_LED2_OFFSET	0x21
 #define MLXPLAT_CPLD_LPC_REG_LED3_OFFSET	0x22
 #define MLXPLAT_CPLD_LPC_REG_LED4_OFFSET	0x23
 #define MLXPLAT_CPLD_LPC_REG_LED5_OFFSET	0x24
+#define MLXPLAT_CPLD_LPC_REG_GP1_OFFSET		0x30
+#define MLXPLAT_CPLD_LPC_REG_WP1_OFFSET		0x31
+#define MLXPLAT_CPLD_LPC_REG_GP2_OFFSET		0x32
+#define MLXPLAT_CPLD_LPC_REG_WP2_OFFSET		0x33
 #define MLXPLAT_CPLD_LPC_REG_AGGR_OFFSET	0x3a
 #define MLXPLAT_CPLD_LPC_REG_AGGR_MASK_OFFSET	0x3b
 #define MLXPLAT_CPLD_LPC_REG_AGGRLO_OFFSET	0x40
@@ -122,12 +129,14 @@
  * @pdev_mux - array of mux platform devices
  * @pdev_hotplug - hotplug platform devices
  * @pdev_led - led platform devices
+ * @pdev_io_regs - register access platform devices
  */
 struct mlxplat_priv {
 	struct platform_device *pdev_i2c;
 	struct platform_device *pdev_mux[MLXPLAT_CPLD_LPC_MUX_DEVS];
 	struct platform_device *pdev_hotplug;
 	struct platform_device *pdev_led;
+	struct platform_device *pdev_io_regs;
 };
 
 /* Regions for LPC I2C controller and LPC base register space */
@@ -813,6 +822,98 @@ static struct mlxreg_core_platform_data mlxplat_default_ng_led_data = {
 		.counter = ARRAY_SIZE(mlxplat_mlxcpld_default_ng_led_data),
 };
 
+/* Platform register access default */
+static struct mlxreg_core_data mlxplat_mlxcpld_default_regs_io_data[] = {
+	{
+		.label = "cpld1_version",
+		.reg = MLXPLAT_CPLD_LPC_REG_CPLD1_VER_OFFSET,
+		.bit = GENMASK(7, 0),
+		.mode = 0444,
+	},
+	{
+		.label = "cpld2_version",
+		.reg = MLXPLAT_CPLD_LPC_REG_CPLD2_VER_OFFSET,
+		.bit = GENMASK(7, 0),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_long_pb",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(0),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_short_pb",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(1),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_aux_pwr_or_ref",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(2),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_main_pwr_fail",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(3),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_sw_reset",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(4),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_fw_reset",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(5),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_hotswap_or_wd",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(6),
+		.mode = 0444,
+	},
+	{
+		.label = "cause_asic_thermal",
+		.reg = MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(7),
+		.mode = 0444,
+	},
+	{
+		.label = "psu1_on",
+		.reg = MLXPLAT_CPLD_LPC_REG_GP1_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(0),
+		.mode = 0200,
+	},
+	{
+		.label = "psu2_on",
+		.reg = MLXPLAT_CPLD_LPC_REG_GP1_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(1),
+		.mode = 0200,
+	},
+	{
+		.label = "pwr_cycle",
+		.reg = MLXPLAT_CPLD_LPC_REG_GP1_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(2),
+		.mode = 0200,
+	},
+	{
+		.label = "select_iio",
+		.reg = MLXPLAT_CPLD_LPC_REG_GP2_OFFSET,
+		.mask = GENMASK(7, 0) & ~BIT(6),
+		.mode = 0644,
+	},
+};
+
+static struct mlxreg_core_platform_data mlxplat_default_regs_io_data = {
+		.data = mlxplat_mlxcpld_default_regs_io_data,
+		.counter = ARRAY_SIZE(mlxplat_mlxcpld_default_regs_io_data),
+};
 
 static bool mlxplat_mlxcpld_writeable_reg(struct device *dev, unsigned int reg)
 {
@@ -822,6 +923,10 @@ static bool mlxplat_mlxcpld_writeable_reg(struct device *dev, unsigned int reg)
 	case MLXPLAT_CPLD_LPC_REG_LED3_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED4_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED5_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP1_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_WP1_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP2_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_WP2_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGR_MASK_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGRLO_MASK_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_PSU_EVENT_OFFSET:
@@ -838,11 +943,18 @@ static bool mlxplat_mlxcpld_writeable_reg(struct device *dev, unsigned int reg)
 static bool mlxplat_mlxcpld_readable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
+	case MLXPLAT_CPLD_LPC_REG_CPLD1_VER_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_CPLD2_VER_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED1_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED2_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED3_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED4_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED5_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP1_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_WP1_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP2_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_WP2_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGR_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGR_MASK_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGRLO_OFFSET:
@@ -864,11 +976,16 @@ static bool mlxplat_mlxcpld_readable_reg(struct device *dev, unsigned int reg)
 static bool mlxplat_mlxcpld_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
+	case MLXPLAT_CPLD_LPC_REG_CPLD1_VER_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_CPLD2_VER_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_RESET_CAUSE_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED1_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED2_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED3_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED4_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_LED5_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP1_OFFSET:
+	case MLXPLAT_CPLD_LPC_REG_GP2_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGR_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGR_MASK_OFFSET:
 	case MLXPLAT_CPLD_LPC_REG_AGGRLO_OFFSET:
@@ -887,6 +1004,11 @@ static bool mlxplat_mlxcpld_volatile_reg(struct device *dev, unsigned int reg)
 	return false;
 }
 
+static const struct reg_default mlxplat_mlxcpld_regmap_default[] = {
+	{ MLXPLAT_CPLD_LPC_REG_WP1_OFFSET, 0x00 },
+	{ MLXPLAT_CPLD_LPC_REG_WP2_OFFSET, 0x00 },
+};
+
 struct mlxplat_mlxcpld_regmap_context {
 	void __iomem *base;
 };
@@ -919,6 +1041,8 @@ static const struct regmap_config mlxplat_mlxcpld_regmap_config = {
 	.writeable_reg = mlxplat_mlxcpld_writeable_reg,
 	.readable_reg = mlxplat_mlxcpld_readable_reg,
 	.volatile_reg = mlxplat_mlxcpld_volatile_reg,
+	.reg_defaults = mlxplat_mlxcpld_regmap_default,
+	.num_reg_defaults = ARRAY_SIZE(mlxplat_mlxcpld_regmap_default),
 	.reg_read = mlxplat_mlxcpld_reg_read,
 	.reg_write = mlxplat_mlxcpld_reg_write,
 };
@@ -930,6 +1054,7 @@ static struct resource mlxplat_mlxcpld_resources[] = {
 static struct platform_device *mlxplat_dev;
 static struct mlxreg_core_hotplug_platform_data *mlxplat_hotplug;
 static struct mlxreg_core_platform_data *mlxplat_led;
+static struct mlxreg_core_platform_data *mlxplat_regs_io;
 
 static int __init mlxplat_dmi_default_matched(const struct dmi_system_id *dmi)
 {
@@ -944,6 +1069,7 @@ static int __init mlxplat_dmi_default_matched(const struct dmi_system_id *dmi)
 	mlxplat_hotplug->deferred_nr =
 		mlxplat_default_channels[i - 1][MLXPLAT_CPLD_GRP_CHNL_NUM - 1];
 	mlxplat_led = &mlxplat_default_led_data;
+	mlxplat_regs_io = &mlxplat_default_regs_io_data;
 
 	return 1;
 };
@@ -978,6 +1104,7 @@ static int __init mlxplat_dmi_msn274x_matched(const struct dmi_system_id *dmi)
 	mlxplat_hotplug->deferred_nr =
 		mlxplat_msn21xx_channels[MLXPLAT_CPLD_GRP_CHNL_NUM - 1];
 	mlxplat_led = &mlxplat_default_led_data;
+	mlxplat_regs_io = &mlxplat_default_regs_io_data;
 
 	return 1;
 };
@@ -1163,7 +1290,7 @@ static int mlxplat_mlxcpld_verify_bus_topology(int *nr)
 static int __init mlxplat_init(void)
 {
 	struct mlxplat_priv *priv;
-	int i, nr, err;
+	int i, j, nr, err;
 
 	if (!dmi_check_system(mlxplat_dmi_table))
 		return -ENODEV;
@@ -1233,6 +1360,15 @@ static int __init mlxplat_init(void)
 		goto fail_platform_mux_register;
 	}
 
+	/* Set default registers. */
+	for (j = 0; j <  mlxplat_mlxcpld_regmap_config.num_reg_defaults; j++) {
+		err = regmap_write(mlxplat_hotplug->regmap,
+				   mlxplat_mlxcpld_regmap_default[j].reg,
+				   mlxplat_mlxcpld_regmap_default[j].def);
+		if (err)
+			goto fail_platform_mux_register;
+	}
+
 	/* Add LED driver. */
 	mlxplat_led->regmap = mlxplat_hotplug->regmap;
 	priv->pdev_led = platform_device_register_resndata(
@@ -1244,14 +1380,31 @@ static int __init mlxplat_init(void)
 		goto fail_platform_hotplug_register;
 	}
 
+	/* Add registers io access driver. */
+	if (mlxplat_regs_io) {
+		mlxplat_regs_io->regmap = mlxplat_hotplug->regmap;
+		priv->pdev_io_regs = platform_device_register_resndata(
+					&mlxplat_dev->dev, "mlxreg-io",
+					PLATFORM_DEVID_NONE, NULL, 0,
+					mlxplat_regs_io,
+					sizeof(*mlxplat_regs_io));
+		if (IS_ERR(priv->pdev_io_regs)) {
+			err = PTR_ERR(priv->pdev_io_regs);
+			goto fail_platform_led_register;
+		}
+	}
+
 	/* Sync registers with hardware. */
 	regcache_mark_dirty(mlxplat_hotplug->regmap);
 	err = regcache_sync(mlxplat_hotplug->regmap);
 	if (err)
-		goto fail_platform_led_register;
+		goto fail_platform_io_regs_register;
 
 	return 0;
 
+fail_platform_io_regs_register:
+	if (mlxplat_regs_io)
+		platform_device_unregister(priv->pdev_io_regs);
 fail_platform_led_register:
 	platform_device_unregister(priv->pdev_led);
 fail_platform_hotplug_register:
@@ -1272,6 +1425,8 @@ static void __exit mlxplat_exit(void)
 	struct mlxplat_priv *priv = platform_get_drvdata(mlxplat_dev);
 	int i;
 
+	if (priv->pdev_io_regs)
+		platform_device_unregister(priv->pdev_io_regs);
 	platform_device_unregister(priv->pdev_led);
 	platform_device_unregister(priv->pdev_hotplug);
 
-- 
2.1.4

Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Darren Hart]

On Sun, May 27, 2018 at 05:34:45PM +0200, Greg Kroah-Hartman wrote:
> On Sun, May 27, 2018 at 03:22:06PM +0000, Vadim Pasternak wrote:
> > 
> > 
> > > -----Original Message-----
> > > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > > Sent: Sunday, May 27, 2018 6:14 PM
> > > To: Vadim Pasternak <vadimp@mellanox.com>
> > > Cc: dvhart@infradead.org; andy.shevchenko@gmail.com; linux-
> > > kernel@vger.kernel.org; platform-driver-x86@vger.kernel.org; jiri@resnulli.us;
> > > Michael Shych <michaelsh@mellanox.com>; ivecera@redhat.com
> > > Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox
> > > register access driver
> > > 
> > > On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> > > > Introduce new Mellanox platform driver to allow access to Mellanox
> > > > programmable device register space trough sysfs interface.
> > > > The driver purpose is to provide sysfs interface for user space for
> > > > the registers essential for system control and monitoring.
> > > > The sets of registers for sysfs access are supposed to be defined per
> > > > system type bases and include the registers related to system resets
> > > > operation, system reset causes monitoring and some kinds of mux selection.
> > > >
> > > > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> > > > ---
> > > > v1->v2:
> > > >  Changed added by Vadim:
> > > >  - Change ---help--- to help in Kconfig, according to new
> > > > requirements;
> > > > v2->v3:
> > > >  Comments pointed out by Darren:
> > > >  - Remove conditional assignment per attribute mode type, because mode
> > > >    will guard against not permitted access.
> > > >    Verified by Vadim.
> > > > ---
> > > >  drivers/platform/mellanox/Kconfig     |  11 ++
> > > >  drivers/platform/mellanox/Makefile    |   1 +
> > > >  drivers/platform/mellanox/mlxreg-io.c | 203
> > > > ++++++++++++++++++++++++++++++++++
> > > >  3 files changed, 215 insertions(+)
> > > >  create mode 100644 drivers/platform/mellanox/mlxreg-io.c
> > > >
> > > > diff --git a/drivers/platform/mellanox/Kconfig
> > > > b/drivers/platform/mellanox/Kconfig
> > > > index 591bccd..ddfae9fc 100644
> > > > --- a/drivers/platform/mellanox/Kconfig
> > > > +++ b/drivers/platform/mellanox/Kconfig
> > > > @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
> > > >  	  This driver handles hot-plug events for the power suppliers, power
> > > >  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
> > > >
> > > > +config MLXREG_IO
> > > > +	tristate "Mellanox platform register access driver support"
> > > > +	depends on REGMAP
> > > > +	depends on HWMON
> > > > +	help
> > > > +	  This driver allows access to Mellanox programmable device register
> > > > +	  space trough sysfs interface. The sets of registers for sysfs access
> > > > +	  are defined per system type bases and includes the registers related
> > > > +	  to system resets operation, system reset causes monitoring and some
> > > > +	  kinds of mux selection.
> > > 
> > > No Documentation/ABI/ entries for these new sysfs files?  Not good :(
> > > 
> > 
> > Thanks Greg for your comment.
> > 
> > Should I call doc file like:
> > Documentation/ABI/stable/sysfs-driver-mlxreg-io
> > ?
> 
> What ever matches the naming scheme for the driver, yes.

Vadim, I'm happy to help out with the docs if you like.

Will you be able to document this in a static way, or is this likely to change
significantly from platform to platform? I ask because of the automated
attribute creation in the code.


-- 
Darren Hart
VMware Open Source Technology Center

RE: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Vadim Pasternak]

> -----Original Message-----
> From: Darren Hart [mailto:dvhart@infradead.org]
> Sent: Friday, June 01, 2018 7:53 PM
> To: Greg KH <gregkh@linuxfoundation.org>
> Cc: Vadim Pasternak <vadimp@mellanox.com>; andy.shevchenko@gmail.com;
> linux-kernel@vger.kernel.org; platform-driver-x86@vger.kernel.org;
> jiri@resnulli.us; Michael Shych <michaelsh@mellanox.com>;
> ivecera@redhat.com
> Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox
> register access driver
> 
> On Sun, May 27, 2018 at 05:34:45PM +0200, Greg Kroah-Hartman wrote:
> > On Sun, May 27, 2018 at 03:22:06PM +0000, Vadim Pasternak wrote:
> > >
> > >
> > > > -----Original Message-----
> > > > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > > > Sent: Sunday, May 27, 2018 6:14 PM
> > > > To: Vadim Pasternak <vadimp@mellanox.com>
> > > > Cc: dvhart@infradead.org; andy.shevchenko@gmail.com; linux-
> > > > kernel@vger.kernel.org; platform-driver-x86@vger.kernel.org;
> > > > jiri@resnulli.us; Michael Shych <michaelsh@mellanox.com>;
> > > > ivecera@redhat.com
> > > > Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support
> > > > for Mellanox register access driver
> > > >
> > > > On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> > > > > Introduce new Mellanox platform driver to allow access to
> > > > > Mellanox programmable device register space trough sysfs interface.
> > > > > The driver purpose is to provide sysfs interface for user space
> > > > > for the registers essential for system control and monitoring.
> > > > > The sets of registers for sysfs access are supposed to be
> > > > > defined per system type bases and include the registers related
> > > > > to system resets operation, system reset causes monitoring and some
> kinds of mux selection.
> > > > >
> > > > > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> > > > > ---
> > > > > v1->v2:
> > > > >  Changed added by Vadim:
> > > > >  - Change ---help--- to help in Kconfig, according to new
> > > > > requirements;
> > > > > v2->v3:
> > > > >  Comments pointed out by Darren:
> > > > >  - Remove conditional assignment per attribute mode type, because
> mode
> > > > >    will guard against not permitted access.
> > > > >    Verified by Vadim.
> > > > > ---
> > > > >  drivers/platform/mellanox/Kconfig     |  11 ++
> > > > >  drivers/platform/mellanox/Makefile    |   1 +
> > > > >  drivers/platform/mellanox/mlxreg-io.c | 203
> > > > > ++++++++++++++++++++++++++++++++++
> > > > >  3 files changed, 215 insertions(+)  create mode 100644
> > > > > drivers/platform/mellanox/mlxreg-io.c
> > > > >
> > > > > diff --git a/drivers/platform/mellanox/Kconfig
> > > > > b/drivers/platform/mellanox/Kconfig
> > > > > index 591bccd..ddfae9fc 100644
> > > > > --- a/drivers/platform/mellanox/Kconfig
> > > > > +++ b/drivers/platform/mellanox/Kconfig
> > > > > @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
> > > > >  	  This driver handles hot-plug events for the power suppliers, power
> > > > >  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
> > > > >
> > > > > +config MLXREG_IO
> > > > > +	tristate "Mellanox platform register access driver support"
> > > > > +	depends on REGMAP
> > > > > +	depends on HWMON
> > > > > +	help
> > > > > +	  This driver allows access to Mellanox programmable device
> register
> > > > > +	  space trough sysfs interface. The sets of registers for sysfs
> access
> > > > > +	  are defined per system type bases and includes the registers
> related
> > > > > +	  to system resets operation, system reset causes monitoring
> and some
> > > > > +	  kinds of mux selection.
> > > >
> > > > No Documentation/ABI/ entries for these new sysfs files?  Not good
> > > > :(
> > > >
> > >
> > > Thanks Greg for your comment.
> > >
> > > Should I call doc file like:
> > > Documentation/ABI/stable/sysfs-driver-mlxreg-io
> > > ?
> >
> > What ever matches the naming scheme for the driver, yes.
> 
> Vadim, I'm happy to help out with the docs if you like.
> 
> Will you be able to document this in a static way, or is this likely to change
> significantly from platform to platform? I ask because of the automated
> attribute creation in the code.
> 
> 
Hi Darren,

Will be great if you can help.
I actually already sent next version of patch with this file.
It'll be not have significant differences  between the different
platforms. However it'll be not the same.
I didn't mention I my file the systems for which the particular
attributes are relevant.

Thanks,
Vadim.

> --
> Darren Hart
> VMware Open Source Technology Center