| /* |
| * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de> |
| * JZ4740 SoC HWMON driver |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the |
| * Free Software Foundation; either version 2 of the License, or (at your |
| * option) any later version. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/interrupt.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include <linux/io.h> |
| |
| #include <linux/completion.h> |
| #include <linux/mfd/core.h> |
| |
| #include <linux/hwmon.h> |
| |
| struct jz4740_hwmon { |
| struct resource *mem; |
| void __iomem *base; |
| |
| int irq; |
| |
| const struct mfd_cell *cell; |
| struct device *hwmon; |
| |
| struct completion read_completion; |
| |
| struct mutex lock; |
| }; |
| |
| static ssize_t jz4740_hwmon_show_name(struct device *dev, |
| struct device_attribute *dev_attr, char *buf) |
| { |
| return sprintf(buf, "jz4740\n"); |
| } |
| |
| static irqreturn_t jz4740_hwmon_irq(int irq, void *data) |
| { |
| struct jz4740_hwmon *hwmon = data; |
| |
| complete(&hwmon->read_completion); |
| return IRQ_HANDLED; |
| } |
| |
| static ssize_t jz4740_hwmon_read_adcin(struct device *dev, |
| struct device_attribute *dev_attr, char *buf) |
| { |
| struct jz4740_hwmon *hwmon = dev_get_drvdata(dev); |
| struct completion *completion = &hwmon->read_completion; |
| long t; |
| unsigned long val; |
| int ret; |
| |
| mutex_lock(&hwmon->lock); |
| |
| INIT_COMPLETION(*completion); |
| |
| enable_irq(hwmon->irq); |
| hwmon->cell->enable(to_platform_device(dev)); |
| |
| t = wait_for_completion_interruptible_timeout(completion, HZ); |
| |
| if (t > 0) { |
| val = readw(hwmon->base) & 0xfff; |
| val = (val * 3300) >> 12; |
| ret = sprintf(buf, "%lu\n", val); |
| } else { |
| ret = t ? t : -ETIMEDOUT; |
| } |
| |
| hwmon->cell->disable(to_platform_device(dev)); |
| disable_irq(hwmon->irq); |
| |
| mutex_unlock(&hwmon->lock); |
| |
| return ret; |
| } |
| |
| static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL); |
| static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL); |
| |
| static struct attribute *jz4740_hwmon_attributes[] = { |
| &dev_attr_name.attr, |
| &dev_attr_in0_input.attr, |
| NULL |
| }; |
| |
| static const struct attribute_group jz4740_hwmon_attr_group = { |
| .attrs = jz4740_hwmon_attributes, |
| }; |
| |
| static int jz4740_hwmon_probe(struct platform_device *pdev) |
| { |
| int ret; |
| struct jz4740_hwmon *hwmon; |
| |
| hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL); |
| if (!hwmon) |
| return -ENOMEM; |
| |
| hwmon->cell = mfd_get_cell(pdev); |
| |
| hwmon->irq = platform_get_irq(pdev, 0); |
| if (hwmon->irq < 0) { |
| dev_err(&pdev->dev, "Failed to get platform irq: %d\n", |
| hwmon->irq); |
| return hwmon->irq; |
| } |
| |
| hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!hwmon->mem) { |
| dev_err(&pdev->dev, "Failed to get platform mmio resource\n"); |
| return -ENOENT; |
| } |
| |
| hwmon->mem = devm_request_mem_region(&pdev->dev, hwmon->mem->start, |
| resource_size(hwmon->mem), pdev->name); |
| if (!hwmon->mem) { |
| dev_err(&pdev->dev, "Failed to request mmio memory region\n"); |
| return -EBUSY; |
| } |
| |
| hwmon->base = devm_ioremap_nocache(&pdev->dev, hwmon->mem->start, |
| resource_size(hwmon->mem)); |
| if (!hwmon->base) { |
| dev_err(&pdev->dev, "Failed to ioremap mmio memory\n"); |
| return -EBUSY; |
| } |
| |
| init_completion(&hwmon->read_completion); |
| mutex_init(&hwmon->lock); |
| |
| platform_set_drvdata(pdev, hwmon); |
| |
| ret = devm_request_irq(&pdev->dev, hwmon->irq, jz4740_hwmon_irq, 0, |
| pdev->name, hwmon); |
| if (ret) { |
| dev_err(&pdev->dev, "Failed to request irq: %d\n", ret); |
| return ret; |
| } |
| disable_irq(hwmon->irq); |
| |
| ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
| if (ret) { |
| dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret); |
| return ret; |
| } |
| |
| hwmon->hwmon = hwmon_device_register(&pdev->dev); |
| if (IS_ERR(hwmon->hwmon)) { |
| ret = PTR_ERR(hwmon->hwmon); |
| goto err_remove_file; |
| } |
| |
| return 0; |
| |
| err_remove_file: |
| sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
| return ret; |
| } |
| |
| static int __devexit jz4740_hwmon_remove(struct platform_device *pdev) |
| { |
| struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev); |
| |
| hwmon_device_unregister(hwmon->hwmon); |
| sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group); |
| |
| return 0; |
| } |
| |
| static struct platform_driver jz4740_hwmon_driver = { |
| .probe = jz4740_hwmon_probe, |
| .remove = jz4740_hwmon_remove, |
| .driver = { |
| .name = "jz4740-hwmon", |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| module_platform_driver(jz4740_hwmon_driver); |
| |
| MODULE_DESCRIPTION("JZ4740 SoC HWMON driver"); |
| MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:jz4740-hwmon"); |