diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-14 17:48:14 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-14 17:48:14 -0700 |
commit | 2ca7d674d7ab2220707b2ada0b690c0e7c95e7ac (patch) | |
tree | 9c0927ed1d540e5fd704c1f82689870786514655 /drivers/hwmon/s3c-hwmon.c | |
parent | 2195d2818c37bdf263865f1e9effccdd9fc5f9d4 (diff) | |
parent | 87d721ad7a37b7650dd710c88dd5c6a5bf9fe996 (diff) |
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (257 commits)
[ARM] Update mach-types
ARM: 5636/1: Move vendor enum to AMBA include
ARM: Fix pfn_valid() for sparse memory
[ARM] orion5x: Add LaCie NAS 2Big Network support
[ARM] pxa/sharpsl_pm: zaurus c3000 aka spitz: fix resume
ARM: 5686/1: at91: Correct AC97 reset line in at91sam9263ek board
ARM: 5640/1: This patch modifies the support of AC97 on the at91sam9263 ek board
ARM: 5689/1: Update default config of HP Jornada 700-series machines
ARM: 5691/1: fix cache aliasing issues between kmap() and kmap_atomic() with highmem
ARM: 5688/1: ks8695_serial: disable_irq() lockup
ARM: 5687/1: fix an oops with highmem
ARM: 5684/1: Add nuc960 platform to w90x900
ARM: 5683/1: Add nuc950 platform to w90x900
ARM: 5682/1: Add cpu.c and dev.c and modify some files of w90p910 platform
ARM: 5626/1: add suspend/resume functions to amba-pl011 serial driver
ARM: 5625/1: fix hard coded 4K resource size in amba bus detection
MMC: MMCI: convert realview MMC to use gpiolib
ARM: 5685/1: Make MMCI driver compile without gpiolib
ARM: implement highpte
ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ
...
Fix up trivial conflict in arch/arm/kernel/signal.c.
It was due to the TIF_NOTIFY_RESUME addition in commit d0420c83f ("KEYS:
Extend TIF_NOTIFY_RESUME to (almost) all architectures") and follow-ups.
Diffstat (limited to 'drivers/hwmon/s3c-hwmon.c')
-rw-r--r-- | drivers/hwmon/s3c-hwmon.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/drivers/hwmon/s3c-hwmon.c b/drivers/hwmon/s3c-hwmon.c new file mode 100644 index 00000000000..3a524f2fe49 --- /dev/null +++ b/drivers/hwmon/s3c-hwmon.c @@ -0,0 +1,405 @@ +/* linux/drivers/hwmon/s3c-hwmon.c + * + * Copyright (C) 2005, 2008, 2009 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX/S3C64XX ADC hwmon support + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> + +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +#include <plat/adc.h> +#include <plat/hwmon.h> + +struct s3c_hwmon_attr { + struct sensor_device_attribute in; + struct sensor_device_attribute label; + char in_name[12]; + char label_name[12]; +}; + +/** + * struct s3c_hwmon - ADC hwmon client information + * @lock: Access lock to serialise the conversions. + * @client: The client we registered with the S3C ADC core. + * @hwmon_dev: The hwmon device we created. + * @attr: The holders for the channel attributes. +*/ +struct s3c_hwmon { + struct semaphore lock; + struct s3c_adc_client *client; + struct device *hwmon_dev; + + struct s3c_hwmon_attr attrs[8]; +}; + +/** + * s3c_hwmon_read_ch - read a value from a given adc channel. + * @dev: The device. + * @hwmon: Our state. + * @channel: The channel we're reading from. + * + * Read a value from the @channel with the proper locking and sleep until + * either the read completes or we timeout awaiting the ADC core to get + * back to us. + */ +static int s3c_hwmon_read_ch(struct device *dev, + struct s3c_hwmon *hwmon, int channel) +{ + int ret; + + ret = down_interruptible(&hwmon->lock); + if (ret < 0) + return ret; + + dev_dbg(dev, "reading channel %d\n", channel); + + ret = s3c_adc_read(hwmon->client, channel); + up(&hwmon->lock); + + return ret; +} + +#ifdef CONFIG_SENSORS_S3C_RAW +/** + * s3c_hwmon_show_raw - show a conversion from the raw channel number. + * @dev: The device that the attribute belongs to. + * @attr: The attribute being read. + * @buf: The result buffer. + * + * This show deals with the raw attribute, registered for each possible + * ADC channel. This does a conversion and returns the raw (un-scaled) + * value returned from the hardware. + */ +static ssize_t s3c_hwmon_show_raw(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct s3c_hwmon *adc = platform_get_drvdata(to_platform_device(dev)); + struct sensor_device_attribute *sa = to_sensor_dev_attr(attr); + int ret; + + ret = s3c_hwmon_read_ch(dev, adc, sa->index); + + return (ret < 0) ? ret : snprintf(buf, PAGE_SIZE, "%d\n", ret); +} + +#define DEF_ADC_ATTR(x) \ + static SENSOR_DEVICE_ATTR(adc##x##_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, x) + +DEF_ADC_ATTR(0); +DEF_ADC_ATTR(1); +DEF_ADC_ATTR(2); +DEF_ADC_ATTR(3); +DEF_ADC_ATTR(4); +DEF_ADC_ATTR(5); +DEF_ADC_ATTR(6); +DEF_ADC_ATTR(7); + +static struct attribute *s3c_hwmon_attrs[9] = { + &sensor_dev_attr_adc0_raw.dev_attr.attr, + &sensor_dev_attr_adc1_raw.dev_attr.attr, + &sensor_dev_attr_adc2_raw.dev_attr.attr, + &sensor_dev_attr_adc3_raw.dev_attr.attr, + &sensor_dev_attr_adc4_raw.dev_attr.attr, + &sensor_dev_attr_adc5_raw.dev_attr.attr, + &sensor_dev_attr_adc6_raw.dev_attr.attr, + &sensor_dev_attr_adc7_raw.dev_attr.attr, + NULL, +}; + +static struct attribute_group s3c_hwmon_attrgroup = { + .attrs = s3c_hwmon_attrs, +}; + +static inline int s3c_hwmon_add_raw(struct device *dev) +{ + return sysfs_create_group(&dev->kobj, &s3c_hwmon_attrgroup); +} + +static inline void s3c_hwmon_remove_raw(struct device *dev) +{ + sysfs_remove_group(&dev->kobj, &s3c_hwmon_attrgroup); +} + +#else + +static inline int s3c_hwmon_add_raw(struct device *dev) { return 0; } +static inline void s3c_hwmon_remove_raw(struct device *dev) { } + +#endif /* CONFIG_SENSORS_S3C_RAW */ + +/** + * s3c_hwmon_ch_show - show value of a given channel + * @dev: The device that the attribute belongs to. + * @attr: The attribute being read. + * @buf: The result buffer. + * + * Read a value from the ADC and scale it before returning it to the + * caller. The scale factor is gained from the channel configuration + * passed via the platform data when the device was registered. + */ +static ssize_t s3c_hwmon_ch_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct sensor_device_attribute *sen_attr = to_sensor_dev_attr(attr); + struct s3c_hwmon *hwmon = platform_get_drvdata(to_platform_device(dev)); + struct s3c_hwmon_pdata *pdata = dev->platform_data; + struct s3c_hwmon_chcfg *cfg; + int ret; + + cfg = pdata->in[sen_attr->index]; + + ret = s3c_hwmon_read_ch(dev, hwmon, sen_attr->index); + if (ret < 0) + return ret; + + ret *= cfg->mult; + ret = DIV_ROUND_CLOSEST(ret, cfg->div); + + return snprintf(buf, PAGE_SIZE, "%d\n", ret); +} + +/** + * s3c_hwmon_label_show - show label name of the given channel. + * @dev: The device that the attribute belongs to. + * @attr: The attribute being read. + * @buf: The result buffer. + * + * Return the label name of a given channel + */ +static ssize_t s3c_hwmon_label_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct sensor_device_attribute *sen_attr = to_sensor_dev_attr(attr); + struct s3c_hwmon_pdata *pdata = dev->platform_data; + struct s3c_hwmon_chcfg *cfg; + + cfg = pdata->in[sen_attr->index]; + + return snprintf(buf, PAGE_SIZE, "%s\n", cfg->name); +} + +/** + * s3c_hwmon_create_attr - create hwmon attribute for given channel. + * @dev: The device to create the attribute on. + * @cfg: The channel configuration passed from the platform data. + * @channel: The ADC channel number to process. + * + * Create the scaled attribute for use with hwmon from the specified + * platform data in @pdata. The sysfs entry is handled by the routine + * s3c_hwmon_ch_show(). + * + * The attribute name is taken from the configuration data if present + * otherwise the name is taken by concatenating in_ with the channel + * number. + */ +static int s3c_hwmon_create_attr(struct device *dev, + struct s3c_hwmon_chcfg *cfg, + struct s3c_hwmon_attr *attrs, + int channel) +{ + struct sensor_device_attribute *attr; + int ret; + + snprintf(attrs->in_name, sizeof(attrs->in_name), "in%d_input", channel); + + attr = &attrs->in; + attr->index = channel; + attr->dev_attr.attr.name = attrs->in_name; + attr->dev_attr.attr.mode = S_IRUGO; + attr->dev_attr.attr.owner = THIS_MODULE; + attr->dev_attr.show = s3c_hwmon_ch_show; + + ret = device_create_file(dev, &attr->dev_attr); + if (ret < 0) { + dev_err(dev, "failed to create input attribute\n"); + return ret; + } + + /* if this has a name, add a label */ + if (cfg->name) { + snprintf(attrs->label_name, sizeof(attrs->label_name), + "in%d_label", channel); + + attr = &attrs->label; + attr->index = channel; + attr->dev_attr.attr.name = attrs->label_name; + attr->dev_attr.attr.mode = S_IRUGO; + attr->dev_attr.attr.owner = THIS_MODULE; + attr->dev_attr.show = s3c_hwmon_label_show; + + ret = device_create_file(dev, &attr->dev_attr); + if (ret < 0) { + device_remove_file(dev, &attrs->in.dev_attr); + dev_err(dev, "failed to create label attribute\n"); + } + } + + return ret; +} + +static void s3c_hwmon_remove_attr(struct device *dev, + struct s3c_hwmon_attr *attrs) +{ + device_remove_file(dev, &attrs->in.dev_attr); + device_remove_file(dev, &attrs->label.dev_attr); +} + +/** + * s3c_hwmon_probe - device probe entry. + * @dev: The device being probed. +*/ +static int __devinit s3c_hwmon_probe(struct platform_device *dev) +{ + struct s3c_hwmon_pdata *pdata = dev->dev.platform_data; + struct s3c_hwmon *hwmon; + int ret = 0; + int i; + + if (!pdata) { + dev_err(&dev->dev, "no platform data supplied\n"); + return -EINVAL; + } + + hwmon = kzalloc(sizeof(struct s3c_hwmon), GFP_KERNEL); + if (hwmon == NULL) { + dev_err(&dev->dev, "no memory\n"); + return -ENOMEM; + } + + platform_set_drvdata(dev, hwmon); + + init_MUTEX(&hwmon->lock); + + /* Register with the core ADC driver. */ + + hwmon->client = s3c_adc_register(dev, NULL, NULL, 0); + if (IS_ERR(hwmon->client)) { + dev_err(&dev->dev, "cannot register adc\n"); + ret = PTR_ERR(hwmon->client); + goto err_mem; + } + + /* add attributes for our adc devices. */ + + ret = s3c_hwmon_add_raw(&dev->dev); + if (ret) + goto err_registered; + + /* register with the hwmon core */ + + hwmon->hwmon_dev = hwmon_device_register(&dev->dev); + if (IS_ERR(hwmon->hwmon_dev)) { + dev_err(&dev->dev, "error registering with hwmon\n"); + ret = PTR_ERR(hwmon->hwmon_dev); + goto err_raw_attribute; + } + + for (i = 0; i < ARRAY_SIZE(pdata->in); i++) { + if (!pdata->in[i]) + continue; + + if (pdata->in[i]->mult >= 0x10000) + dev_warn(&dev->dev, + "channel %d multiplier too large\n", + i); + + ret = s3c_hwmon_create_attr(&dev->dev, pdata->in[i], + &hwmon->attrs[i], i); + if (ret) { + dev_err(&dev->dev, + "error creating channel %d\n", i); + + for (i--; i >= 0; i--) + s3c_hwmon_remove_attr(&dev->dev, + &hwmon->attrs[i]); + + goto err_hwmon_register; + } + } + + return 0; + + err_hwmon_register: + hwmon_device_unregister(hwmon->hwmon_dev); + + err_raw_attribute: + s3c_hwmon_remove_raw(&dev->dev); + + err_registered: + s3c_adc_release(hwmon->client); + + err_mem: + kfree(hwmon); + return ret; +} + +static int __devexit s3c_hwmon_remove(struct platform_device *dev) +{ + struct s3c_hwmon *hwmon = platform_get_drvdata(dev); + int i; + + s3c_hwmon_remove_raw(&dev->dev); + + for (i = 0; i < ARRAY_SIZE(hwmon->attrs); i++) + s3c_hwmon_remove_attr(&dev->dev, &hwmon->attrs[i]); + + hwmon_device_unregister(hwmon->hwmon_dev); + s3c_adc_release(hwmon->client); + + return 0; +} + +static struct platform_driver s3c_hwmon_driver = { + .driver = { + .name = "s3c-hwmon", + .owner = THIS_MODULE, + }, + .probe = s3c_hwmon_probe, + .remove = __devexit_p(s3c_hwmon_remove), +}; + +static int __init s3c_hwmon_init(void) +{ + return platform_driver_register(&s3c_hwmon_driver); +} + +static void __exit s3c_hwmon_exit(void) +{ + platform_driver_unregister(&s3c_hwmon_driver); +} + +module_init(s3c_hwmon_init); +module_exit(s3c_hwmon_exit); + +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_DESCRIPTION("S3C ADC HWMon driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:s3c-hwmon"); |