From: Ben Dooks Date: Sat, 18 Jul 2009 09:12:28 +0000 (+0100) Subject: ARM: HWMON: S3C24XX series ADC driver X-Git-Tag: v2.6.32-rc1~49^2~1^2~14^2~18^2 X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=bff78650a2b0ed42b8fb134b6a9b387e00027d67 ARM: HWMON: S3C24XX series ADC driver Add support for the ADC controller on the S3C series of processors to drivers/hwmon for use with hardware monitoring systems. Signed-off-by: Ben Dooks Acked-by: Jean Delvare Signed-off-by: Ben Dooks --- diff --git a/arch/arm/plat-s3c/include/plat/hwmon.h b/arch/arm/plat-s3c/include/plat/hwmon.h new file mode 100644 index 0000000..1ba88ea --- /dev/null +++ b/arch/arm/plat-s3c/include/plat/hwmon.h @@ -0,0 +1,41 @@ +/* linux/arch/arm/plat-s3c/include/plat/hwmon.h + * + * Copyright 2005 Simtec Electronics + * Ben Dooks + * http://armlinux.simtec.co.uk/ + * + * S3C - HWMon interface for ADC + * + * 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. +*/ + +#ifndef __ASM_ARCH_ADC_HWMON_H +#define __ASM_ARCH_ADC_HWMON_H __FILE__ + +/** + * s3c_hwmon_chcfg - channel configuration + * @name: The name to give this channel. + * @mult: Multiply the ADC value read by this. + * @div: Divide the value from the ADC by this. + * + * The value read from the ADC is converted to a value that + * hwmon expects (mV) by result = (value_read * @mult) / @div. + */ +struct s3c_hwmon_chcfg { + const char *name; + unsigned int mult; + unsigned int div; +}; + +/** + * s3c_hwmon_pdata - HWMON platform data + * @in: One configuration for each possible channel used. + */ +struct s3c_hwmon_pdata { + struct s3c_hwmon_chcfg *in[8]; +}; + +#endif /* __ASM_ARCH_ADC_HWMON_H */ + diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 2d50166..2e25b7a 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -702,6 +702,23 @@ config SENSORS_SHT15 This driver can also be built as a module. If so, the module will be called sht15. +config SENSORS_S3C + tristate "S3C24XX/S3C64XX Inbuilt ADC" + depends on ARCH_S3C2410 || ARCH_S3C64XX + help + If you say yes here you get support for the on-board ADCs of + the Samsung S3C24XX or S3C64XX series of SoC + + This driver can also be built as a module. If so, the module + will be called s3c-hwmo. + +config SENSORS_S3C_RAW + bool "Include raw channel attributes in sysfs" + depends on SENSORS_S3C + help + Say Y here if you want to include raw copies of all the ADC + channels in sysfs. + config SENSORS_SIS5595 tristate "Silicon Integrated Systems Corp. SiS5595" depends on PCI diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index b793dce..7f239a2 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_SENSORS_MAX6650) += max6650.o obj-$(CONFIG_SENSORS_PC87360) += pc87360.o obj-$(CONFIG_SENSORS_PC87427) += pc87427.o obj-$(CONFIG_SENSORS_PCF8591) += pcf8591.o +obj-$(CONFIG_SENSORS_S3C) += s3c-hwmon.o obj-$(CONFIG_SENSORS_SHT15) += sht15.o obj-$(CONFIG_SENSORS_SIS5595) += sis5595.o obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o diff --git a/drivers/hwmon/s3c-hwmon.c b/drivers/hwmon/s3c-hwmon.c new file mode 100644 index 0000000..3a524f2 --- /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 + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include + +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 "); +MODULE_DESCRIPTION("S3C ADC HWMon driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:s3c-hwmon");