diff options
Diffstat (limited to 'drivers/platform/mellanox')
| -rw-r--r-- | drivers/platform/mellanox/Kconfig | 25 | ||||
| -rw-r--r-- | drivers/platform/mellanox/Makefile | 6 | ||||
| -rw-r--r-- | drivers/platform/mellanox/mlxreg-hotplug.c | 514 |
3 files changed, 545 insertions, 0 deletions
diff --git a/drivers/platform/mellanox/Kconfig b/drivers/platform/mellanox/Kconfig new file mode 100644 index 000000000000..d73529203327 --- /dev/null +++ b/drivers/platform/mellanox/Kconfig @@ -0,0 +1,25 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Platform support for Mellanox hardware +# + +menuconfig MELLANOX_PLATFORM + bool "Platform support for Mellanox hardware" + depends on X86 || COMPILE_TEST + ---help--- + Say Y here to get to see options for platform support for + Mellanox systems. This option alone does not add any kernel code. + + If you say N, all options in this submenu will be skipped and disabled. + +if MELLANOX_PLATFORM + +config MLXREG_HOTPLUG + tristate "Mellanox platform hotplug driver support" + depends on HWMON + depends on I2C + ---help--- + This driver handles hot-plug events for the power suppliers, power + cables and fans on the wide range Mellanox IB and Ethernet systems. + +endif # MELLANOX_PLATFORM diff --git a/drivers/platform/mellanox/Makefile b/drivers/platform/mellanox/Makefile new file mode 100644 index 000000000000..7c8385e497a8 --- /dev/null +++ b/drivers/platform/mellanox/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for linux/drivers/platform/mellanox +# Mellanox Platform-Specific Drivers +# +obj-$(CONFIG_MLXREG_HOTPLUG) += mlxreg-hotplug.o diff --git a/drivers/platform/mellanox/mlxreg-hotplug.c b/drivers/platform/mellanox/mlxreg-hotplug.c new file mode 100644 index 000000000000..5cfc82ba34be --- /dev/null +++ b/drivers/platform/mellanox/mlxreg-hotplug.c @@ -0,0 +1,514 @@ +/* + * Copyright (c) 2016-2018 Mellanox Technologies. All rights reserved. + * Copyright (c) 2016-2018 Vadim Pasternak <vadimp@mellanox.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <linux/bitops.h> +#include <linux/device.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_data/mlxreg.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/wait.h> +#include <linux/workqueue.h> + +/* Offset of event and mask registers from status register */ +#define MLXREG_HOTPLUG_EVENT_OFF 1 +#define MLXREG_HOTPLUG_MASK_OFF 2 +#define MLXREG_HOTPLUG_AGGR_MASK_OFF 1 + +#define MLXREG_HOTPLUG_ATTRS_NUM 8 + +/** + * enum mlxreg_hotplug_attr_type - sysfs attributes for hotplug events: + * @MLXREG_HOTPLUG_ATTR_TYPE_PSU: power supply unit attribute; + * @MLXREG_HOTPLUG_ATTR_TYPE_PWR: power cable attribute; + * @MLXREG_HOTPLUG_ATTR_TYPE_FAN: FAN drawer attribute; + */ +enum mlxreg_hotplug_attr_type { + MLXREG_HOTPLUG_ATTR_TYPE_PSU, + MLXREG_HOTPLUG_ATTR_TYPE_PWR, + MLXREG_HOTPLUG_ATTR_TYPE_FAN, +}; + +/** + * struct mlxreg_hotplug_priv_data - platform private data: + * @irq: platform interrupt number; + * @pdev: platform device; + * @plat: platform data; + * @hwmon: hwmon device; + * @mlxreg_hotplug_attr: sysfs attributes array; + * @mlxreg_hotplug_dev_attr: sysfs sensor device attribute array; + * @group: sysfs attribute group; + * @groups: list of sysfs attribute group for hwmon registration; + * @dwork: delayed work template; + * @lock: spin lock; + * @aggr_cache: last value of aggregation register status; + * @psu_cache: last value of PSU register status; + * @pwr_cache: last value of power register status; + * @fan_cache: last value of FAN register status; + */ +struct mlxreg_hotplug_priv_data { + int irq; + struct platform_device *pdev; + struct mlxreg_hotplug_platform_data *plat; + struct device *hwmon; + struct attribute *mlxreg_hotplug_attr[MLXREG_HOTPLUG_ATTRS_NUM + 1]; + struct sensor_device_attribute_2 + mlxreg_hotplug_dev_attr[MLXREG_HOTPLUG_ATTRS_NUM]; + struct attribute_group group; + const struct attribute_group *groups[2]; + struct delayed_work dwork; + spinlock_t lock; + u8 aggr_cache; + u8 psu_cache; + u8 pwr_cache; + u8 fan_cache; +}; + +static ssize_t mlxreg_hotplug_attr_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct mlxreg_hotplug_priv_data *priv = platform_get_drvdata(pdev); + int index = to_sensor_dev_attr_2(attr)->index; + int nr = to_sensor_dev_attr_2(attr)->nr; + u8 reg_val = 0; + + switch (nr) { + case MLXREG_HOTPLUG_ATTR_TYPE_PSU: + /* Bit = 0 : PSU is present. */ + reg_val = !!!(inb(priv->plat->psu_reg_offset) & BIT(index)); + break; + + case MLXREG_HOTPLUG_ATTR_TYPE_PWR: + /* Bit = 1 : power cable is attached. */ + reg_val = !!(inb(priv->plat->pwr_reg_offset) & BIT(index % + priv->plat->pwr_count)); + break; + + case MLXREG_HOTPLUG_ATTR_TYPE_FAN: + /* Bit = 0 : FAN is present. */ + reg_val = !!!(inb(priv->plat->fan_reg_offset) & BIT(index % + priv->plat->fan_count)); + break; + } + + return sprintf(buf, "%u\n", reg_val); +} + +#define PRIV_ATTR(i) priv->mlxreg_hotplug_attr[i] +#define PRIV_DEV_ATTR(i) priv->mlxreg_hotplug_dev_attr[i] +static int mlxreg_hotplug_attr_init(struct mlxreg_hotplug_priv_data *priv) +{ + int num_attrs = priv->plat->psu_count + priv->plat->pwr_count + + priv->plat->fan_count; + int i; + + priv->group.attrs = devm_kzalloc(&priv->pdev->dev, num_attrs * + sizeof(struct attribute *), + GFP_KERNEL); + if (!priv->group.attrs) + return -ENOMEM; + + for (i = 0; i < num_attrs; i++) { + PRIV_ATTR(i) = &PRIV_DEV_ATTR(i).dev_attr.attr; + + if (i < priv->plat->psu_count) { + PRIV_ATTR(i)->name = devm_kasprintf(&priv->pdev->dev, + GFP_KERNEL, "psu%u", i + 1); + PRIV_DEV_ATTR(i).nr = MLXREG_HOTPLUG_ATTR_TYPE_PSU; + } else if (i < priv->plat->psu_count + priv->plat->pwr_count) { + PRIV_ATTR(i)->name = devm_kasprintf(&priv->pdev->dev, + GFP_KERNEL, "pwr%u", i % + priv->plat->pwr_count + 1); + PRIV_DEV_ATTR(i).nr = MLXREG_HOTPLUG_ATTR_TYPE_PWR; + } else { + PRIV_ATTR(i)->name = devm_kasprintf(&priv->pdev->dev, + GFP_KERNEL, "fan%u", i % + priv->plat->fan_count + 1); + PRIV_DEV_ATTR(i).nr = MLXREG_HOTPLUG_ATTR_TYPE_FAN; + } + + if (!PRIV_ATTR(i)->name) { + dev_err(&priv->pdev->dev, "Memory allocation failed for sysfs attribute %d.\n", + i + 1); + return -ENOMEM; + } + + PRIV_DEV_ATTR(i).dev_attr.attr.name = PRIV_ATTR(i)->name; + PRIV_DEV_ATTR(i).dev_attr.attr.mode = S_IRUGO; + PRIV_DEV_ATTR(i).dev_attr.show = mlxreg_hotplug_attr_show; + PRIV_DEV_ATTR(i).index = i; + sysfs_attr_init(&PRIV_DEV_ATTR(i).dev_attr.attr); + } + + priv->group.attrs = priv->mlxreg_hotplug_attr; + priv->groups[0] = &priv->group; + priv->groups[1] = NULL; + + return 0; +} + +static int mlxreg_hotplug_device_create(struct device *dev, + struct mlxreg_hotplug_device *item) +{ + item->adapter = i2c_get_adapter(item->bus); + if (!item->adapter) { + dev_err(dev, "Failed to get adapter for bus %d\n", + item->bus); + return -EFAULT; + } + + item->client = i2c_new_device(item->adapter, &item->brdinfo); + if (!item->client) { + dev_err(dev, "Failed to create client %s at bus %d at addr 0x%02x\n", + item->brdinfo.type, item->bus, item->brdinfo.addr); + i2c_put_adapter(item->adapter); + item->adapter = NULL; + return -EFAULT; + } + + return 0; +} + +static void mlxreg_hotplug_device_destroy(struct mlxreg_hotplug_device *item) +{ + if (item->client) { + i2c_unregister_device(item->client); + item->client = NULL; + } + + if (item->adapter) { + i2c_put_adapter(item->adapter); + item->adapter = NULL; + } +} + +static inline void +mlxreg_hotplug_work_helper(struct device *dev, + struct mlxreg_hotplug_device *item, u8 is_inverse, + u16 offset, u8 mask, u8 *cache) +{ + u8 val, asserted; + int bit; + + /* Mask event. */ + outb(0, offset + MLXREG_HOTPLUG_MASK_OFF); + /* Read status. */ + val = inb(offset) & mask; + asserted = *cache ^ val; + *cache = val; + + /* + * Validate if item related to received signal type is valid. + * It should never happen, excepted the situation when some + * piece of hardware is broken. In such situation just produce + * error message and return. Caller must continue to handle the + * signals from other devices if any. + */ + if (unlikely(!item)) { + dev_err(dev, "False signal is received: register at offset 0x%02x, mask 0x%02x.\n", + offset, mask); + return; + } + + for_each_set_bit(bit, (unsigned long *)&asserted, 8) { + if (val & BIT(bit)) { + if (is_inverse) + mlxreg_hotplug_device_destroy(item + bit); + else + mlxreg_hotplug_device_create(dev, item + bit); + } else { + if (is_inverse) + mlxreg_hotplug_device_create(dev, item + bit); + else + mlxreg_hotplug_device_destroy(item + bit); + } + } + + /* Acknowledge event. */ + outb(0, offset + MLXREG_HOTPLUG_EVENT_OFF); + /* Unmask event. */ + outb(mask, offset + MLXREG_HOTPLUG_MASK_OFF); +} + +/* + * mlxreg_hotplug_work_handler - performs traversing of CPLD interrupt + * registers according to the below hierarchy schema: + * + * Aggregation registers (status/mask) + * PSU registers: *---* + * *-----------------* | | + * |status/event/mask|----->| * | + * *-----------------* | | + * Power registers: | | + * *-----------------* | | + * |status/event/mask|----->| * |---> CPU + * *-----------------* | | + * FAN registers: + * *-----------------* | | + * |status/event/mask|----->| * | + * *-----------------* | | + * *---* + * In case some system changed are detected: FAN in/out, PSU in/out, power + * cable attached/detached, relevant device is created or destroyed. + */ +static void mlxreg_hotplug_work_handler(struct work_struct *work) +{ + struct mlxreg_hotplug_priv_data *priv = container_of(work, + struct mlxreg_hotplug_priv_data, dwork.work); + u8 val, aggr_asserted; + unsigned long flags; + + /* Mask aggregation event. */ + outb(0, priv->plat->top_aggr_offset + MLXREG_HOTPLUG_AGGR_MASK_OFF); + /* Read aggregation status. */ + val = inb(priv->plat->top_aggr_offset) & priv->plat->top_aggr_mask; + aggr_asserted = priv->aggr_cache ^ val; + priv->aggr_cache = val; + + /* Handle PSU configuration changes. */ + if (aggr_asserted & priv->plat->top_aggr_psu_mask) + mlxreg_hotplug_work_helper(&priv->pdev->dev, priv->plat->psu, + 1, priv->plat->psu_reg_offset, + priv->plat->psu_mask, + &priv->psu_cache); + + /* Handle power cable configuration changes. */ + if (aggr_asserted & priv->plat->top_aggr_pwr_mask) + mlxreg_hotplug_work_helper(&priv->pdev->dev, priv->plat->pwr, + 0, priv->plat->pwr_reg_offset, + priv->plat->pwr_mask, + &priv->pwr_cache); + + /* Handle FAN configuration changes. */ + if (aggr_asserted & priv->plat->top_aggr_fan_mask) + mlxreg_hotplug_work_helper(&priv->pdev->dev, priv->plat->fan, + 1, priv->plat->fan_reg_offset, + priv->plat->fan_mask, + &priv->fan_cache); + + if (aggr_asserted) { + spin_lock_irqsave(&priv->lock, flags); + + /* + * It is possible, that some signals have been inserted, while + * interrupt has been masked by mlxreg_hotplug_work_handler. + * In this case such signals will be missed. In order to handle + * these signals delayed work is canceled and work task + * re-scheduled for immediate execution. It allows to handle + * missed signals, if any. In other case work handler just + * validates that no new signals have been received during + * masking. + */ + cancel_delayed_work(&priv->dwork); + schedule_delayed_work(&priv->dwork, 0); + + spin_unlock_irqrestore(&priv->lock, flags); + + return; + } + + /* Unmask aggregation event (no need acknowledge). */ + outb(priv->plat->top_aggr_mask, priv->plat->top_aggr_offset + + MLXREG_HOTPLUG_AGGR_MASK_OFF); +} + +static void mlxreg_hotplug_set_irq(struct mlxreg_hotplug_priv_data *priv) +{ + /* Clear psu presense event. */ + outb(0, priv->plat->psu_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + /* Set psu initial status as mask and unmask psu event. */ + priv->psu_cache = priv->plat->psu_mask; + outb(priv->plat->psu_mask, priv->plat->psu_reg_offset + + MLXREG_HOTPLUG_MASK_OFF); + + /* Clear power cable event. */ + outb(0, priv->plat->pwr_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + /* Keep power initial status as zero and unmask power event. */ + outb(priv->plat->pwr_mask, priv->plat->pwr_reg_offset + + MLXREG_HOTPLUG_MASK_OFF); + + /* Clear fan presense event. */ + outb(0, priv->plat->fan_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + /* Set fan initial status as mask and unmask fan event. */ + priv->fan_cache = priv->plat->fan_mask; + outb(priv->plat->fan_mask, priv->plat->fan_reg_offset + + MLXREG_HOTPLUG_MASK_OFF); + + /* Keep aggregation initial status as zero and unmask events. */ + outb(priv->plat->top_aggr_mask, priv->plat->top_aggr_offset + + MLXREG_HOTPLUG_AGGR_MASK_OFF); + + /* Invoke work handler for initializing hot plug devices setting. */ + mlxreg_hotplug_work_handler(&priv->dwork.work); + + enable_irq(priv->irq); +} + +static void mlxreg_hotplug_unset_irq(struct mlxreg_hotplug_priv_data *priv) +{ + int i; + + disable_irq(priv->irq); + cancel_delayed_work_sync(&priv->dwork); + + /* Mask aggregation event. */ + outb(0, priv->plat->top_aggr_offset + MLXREG_HOTPLUG_AGGR_MASK_OFF); + + /* Mask psu presense event. */ + outb(0, priv->plat->psu_reg_offset + MLXREG_HOTPLUG_MASK_OFF); + /* Clear psu presense event. */ + outb(0, priv->plat->psu_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + + /* Mask power cable event. */ + outb(0, priv->plat->pwr_reg_offset + MLXREG_HOTPLUG_MASK_OFF); + /* Clear power cable event. */ + outb(0, priv->plat->pwr_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + + /* Mask fan presense event. */ + outb(0, priv->plat->fan_reg_offset + MLXREG_HOTPLUG_MASK_OFF); + /* Clear fan presense event. */ + outb(0, priv->plat->fan_reg_offset + MLXREG_HOTPLUG_EVENT_OFF); + + /* Remove all the attached devices. */ + for (i = 0; i < priv->plat->psu_count; i++) + mlxreg_hotplug_device_destroy(priv->plat->psu + i); + + for (i = 0; i < priv->plat->pwr_count; i++) + mlxreg_hotplug_device_destroy(priv->plat->pwr + i); + + for (i = 0; i < priv->plat->fan_count; i++) + mlxreg_hotplug_device_destroy(priv->plat->fan + i); +} + +static irqreturn_t mlxreg_hotplug_irq_handler(int irq, void *dev) +{ + struct mlxreg_hotplug_priv_data *priv = + (struct mlxreg_hotplug_priv_data *)dev; + + /* Schedule work task for immediate execution.*/ + schedule_delayed_work(&priv->dwork, 0); + + return IRQ_HANDLED; +} + +static int mlxreg_hotplug_probe(struct platform_device *pdev) +{ + struct mlxreg_hotplug_platform_data *pdata; + struct mlxreg_hotplug_priv_data *priv; + int err; + + pdata = dev_get_platdata(&pdev->dev); + if (!pdata) { + dev_err(&pdev->dev, "Failed to get platform data.\n"); + return -EINVAL; + } + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->pdev = pdev; + priv->plat = pdata; + + priv->irq = platform_get_irq(pdev, 0); + if (priv->irq < 0) { + dev_err(&pdev->dev, "Failed to get platform irq: %d\n", + priv->irq); + return priv->irq; + } + + err = devm_request_irq(&pdev->dev, priv->irq, + mlxreg_hotplug_irq_handler, 0, pdev->name, + priv); + if (err) { + dev_err(&pdev->dev, "Failed to request irq: %d\n", err); + return err; + } + disable_irq(priv->irq); + + INIT_DELAYED_WORK(&priv->dwork, mlxreg_hotplug_work_handler); + spin_lock_init(&priv->lock); + + err = mlxreg_hotplug_attr_init(priv); + if (err) { + dev_err(&pdev->dev, "Failed to allocate attributes: %d\n", err); + return err; + } + + priv->hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, + "mlxreg_hotplug", 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); + } + + platform_set_drvdata(pdev, priv); + + /* Perform initial interrupts setup. */ + mlxreg_hotplug_set_irq(priv); + + return 0; +} + +static int mlxreg_hotplug_remove(struct platform_device *pdev) +{ + struct mlxreg_hotplug_priv_data *priv = platform_get_drvdata(pdev); + + /* Clean interrupts setup. */ + mlxreg_hotplug_unset_irq(priv); + + return 0; +} + +static struct platform_driver mlxreg_hotplug_driver = { + .driver = { + .name = "mlxreg-hotplug", + }, + .probe = mlxreg_hotplug_probe, + .remove = mlxreg_hotplug_remove, +}; + +module_platform_driver(mlxreg_hotplug_driver); + +MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>"); +MODULE_DESCRIPTION("Mellanox regmap hotplug platform driver"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("platform:mlxreg-hotplug"); |