diff options
Diffstat (limited to 'drivers/hwmon/mc13783-adc.c')
| -rw-r--r-- | drivers/hwmon/mc13783-adc.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/drivers/hwmon/mc13783-adc.c b/drivers/hwmon/mc13783-adc.c new file mode 100644 index 000000000..78fe8759d --- /dev/null +++ b/drivers/hwmon/mc13783-adc.c @@ -0,0 +1,340 @@ +/* + * Driver for the ADC on Freescale Semiconductor MC13783 and MC13892 PMICs. + * + * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright (C) 2009 Sascha Hauer, Pengutronix + * + * 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. + * 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., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <linux/mfd/mc13xxx.h> +#include <linux/platform_device.h> +#include <linux/hwmon-sysfs.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/hwmon.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/err.h> + +#define DRIVER_NAME "mc13783-adc" + +/* platform device id driver data */ +#define MC13783_ADC_16CHANS 1 +#define MC13783_ADC_BPDIV2 2 + +struct mc13783_adc_priv { + struct mc13xxx *mc13xxx; + struct device *hwmon_dev; + char name[PLATFORM_NAME_SIZE]; +}; + +static ssize_t name_show(struct device *dev, struct device_attribute *devattr, + char *buf) +{ + struct mc13783_adc_priv *priv = dev_get_drvdata(dev); + + return sprintf(buf, "%s\n", priv->name); +} + +static int mc13783_adc_read(struct device *dev, + struct device_attribute *devattr, unsigned int *val) +{ + struct mc13783_adc_priv *priv = dev_get_drvdata(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + unsigned int channel = attr->index; + unsigned int sample[4]; + int ret; + + ret = mc13xxx_adc_do_conversion(priv->mc13xxx, + MC13XXX_ADC_MODE_MULT_CHAN, + channel, 0, 0, sample); + if (ret) + return ret; + + /* ADIN7 subchannels */ + if (channel >= 16) + channel = 7; + + channel &= 0x7; + + *val = (sample[channel % 4] >> (channel > 3 ? 14 : 2)) & 0x3ff; + + return 0; +} + +static ssize_t mc13783_adc_read_bp(struct device *dev, + struct device_attribute *devattr, char *buf) +{ + unsigned val; + struct platform_device *pdev = to_platform_device(dev); + kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data; + int ret = mc13783_adc_read(dev, devattr, &val); + + if (ret) + return ret; + + if (driver_data & MC13783_ADC_BPDIV2) + val = DIV_ROUND_CLOSEST(val * 9, 2); + else + /* + * BP (channel 2) reports with offset 2.4V to the actual value + * to fit the input range of the ADC. unit = 2.25mV = 9/4 mV. + */ + val = DIV_ROUND_CLOSEST(val * 9, 4) + 2400; + + return sprintf(buf, "%u\n", val); +} + +static ssize_t mc13783_adc_read_gp(struct device *dev, + struct device_attribute *devattr, char *buf) +{ + unsigned val; + int ret = mc13783_adc_read(dev, devattr, &val); + + if (ret) + return ret; + + /* + * input range is [0, 2.3V], val has 10 bits, so each bit + * is worth 9/4 mV. + */ + val = DIV_ROUND_CLOSEST(val * 9, 4); + + return sprintf(buf, "%u\n", val); +} + +static ssize_t mc13783_adc_read_uid(struct device *dev, + struct device_attribute *devattr, char *buf) +{ + unsigned int val; + struct platform_device *pdev = to_platform_device(dev); + kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data; + int ret = mc13783_adc_read(dev, devattr, &val); + + if (ret) + return ret; + + if (driver_data & MC13783_ADC_BPDIV2) + /* MC13892 have 1/2 divider, input range is [0, 4.800V] */ + val = DIV_ROUND_CLOSEST(val * 4800, 1024); + else + /* MC13783 have 0.9 divider, input range is [0, 2.555V] */ + val = DIV_ROUND_CLOSEST(val * 2555, 1024); + + return sprintf(buf, "%u\n", val); +} + +static ssize_t mc13783_adc_read_temp(struct device *dev, + struct device_attribute *devattr, char *buf) +{ + unsigned int val; + struct platform_device *pdev = to_platform_device(dev); + kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data; + int ret = mc13783_adc_read(dev, devattr, &val); + + if (ret) + return ret; + + if (driver_data & MC13783_ADC_BPDIV2) { + /* + * MC13892: + * Die Temperature Read Out Code at 25C 680 + * Temperature change per LSB +0.4244C + */ + ret = DIV_ROUND_CLOSEST(-2635920 + val * 4244, 10); + } else { + /* + * MC13783: + * Die Temperature Read Out Code at 25C 282 + * Temperature change per LSB -1.14C + */ + ret = 346480 - 1140 * val; + } + + return sprintf(buf, "%d\n", ret); +} + +static DEVICE_ATTR_RO(name); +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, mc13783_adc_read_bp, NULL, 2); +static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, mc13783_adc_read_gp, NULL, 5); +static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, mc13783_adc_read_gp, NULL, 6); +static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, mc13783_adc_read_gp, NULL, 7); +static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, mc13783_adc_read_gp, NULL, 8); +static SENSOR_DEVICE_ATTR(in9_input, S_IRUGO, mc13783_adc_read_gp, NULL, 9); +static SENSOR_DEVICE_ATTR(in10_input, S_IRUGO, mc13783_adc_read_gp, NULL, 10); +static SENSOR_DEVICE_ATTR(in11_input, S_IRUGO, mc13783_adc_read_gp, NULL, 11); +static SENSOR_DEVICE_ATTR(in12_input, S_IRUGO, mc13783_adc_read_gp, NULL, 12); +static SENSOR_DEVICE_ATTR(in13_input, S_IRUGO, mc13783_adc_read_gp, NULL, 13); +static SENSOR_DEVICE_ATTR(in14_input, S_IRUGO, mc13783_adc_read_gp, NULL, 14); +static SENSOR_DEVICE_ATTR(in15_input, S_IRUGO, mc13783_adc_read_gp, NULL, 15); +static SENSOR_DEVICE_ATTR(in16_input, S_IRUGO, mc13783_adc_read_uid, NULL, 16); +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, + mc13783_adc_read_temp, NULL, 17); + +static struct attribute *mc13783_attr_base[] = { + &dev_attr_name.attr, + &sensor_dev_attr_in2_input.dev_attr.attr, + &sensor_dev_attr_in5_input.dev_attr.attr, + &sensor_dev_attr_in6_input.dev_attr.attr, + &sensor_dev_attr_in7_input.dev_attr.attr, + &sensor_dev_attr_in16_input.dev_attr.attr, + &sensor_dev_attr_temp1_input.dev_attr.attr, + NULL +}; + +static const struct attribute_group mc13783_group_base = { + .attrs = mc13783_attr_base, +}; + +/* these are only used if MC13783_ADC_16CHANS is provided in driver data */ +static struct attribute *mc13783_attr_16chans[] = { + &sensor_dev_attr_in8_input.dev_attr.attr, + &sensor_dev_attr_in9_input.dev_attr.attr, + &sensor_dev_attr_in10_input.dev_attr.attr, + &sensor_dev_attr_in11_input.dev_attr.attr, + NULL +}; + +static const struct attribute_group mc13783_group_16chans = { + .attrs = mc13783_attr_16chans, +}; + +/* last four channels may be occupied by the touchscreen */ +static struct attribute *mc13783_attr_ts[] = { + &sensor_dev_attr_in12_input.dev_attr.attr, + &sensor_dev_attr_in13_input.dev_attr.attr, + &sensor_dev_attr_in14_input.dev_attr.attr, + &sensor_dev_attr_in15_input.dev_attr.attr, + NULL +}; + +static const struct attribute_group mc13783_group_ts = { + .attrs = mc13783_attr_ts, +}; + +static int mc13783_adc_use_touchscreen(struct platform_device *pdev) +{ + struct mc13783_adc_priv *priv = platform_get_drvdata(pdev); + unsigned flags = mc13xxx_get_flags(priv->mc13xxx); + + return flags & MC13XXX_USE_TOUCHSCREEN; +} + +static int __init mc13783_adc_probe(struct platform_device *pdev) +{ + struct mc13783_adc_priv *priv; + int ret; + const struct platform_device_id *id = platform_get_device_id(pdev); + char *dash; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->mc13xxx = dev_get_drvdata(pdev->dev.parent); + snprintf(priv->name, ARRAY_SIZE(priv->name), "%s", id->name); + dash = strchr(priv->name, '-'); + if (dash) + *dash = '\0'; + + platform_set_drvdata(pdev, priv); + + /* Register sysfs hooks */ + ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_base); + if (ret) + return ret; + + if (id->driver_data & MC13783_ADC_16CHANS) { + ret = sysfs_create_group(&pdev->dev.kobj, + &mc13783_group_16chans); + if (ret) + goto out_err_create_16chans; + } + + if (!mc13783_adc_use_touchscreen(pdev)) { + ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_ts); + if (ret) + goto out_err_create_ts; + } + + priv->hwmon_dev = hwmon_device_register(&pdev->dev); + if (IS_ERR(priv->hwmon_dev)) { + ret = PTR_ERR(priv->hwmon_dev); + dev_err(&pdev->dev, + "hwmon_device_register failed with %d.\n", ret); + goto out_err_register; + } + + return 0; + +out_err_register: + + if (!mc13783_adc_use_touchscreen(pdev)) + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts); +out_err_create_ts: + + if (id->driver_data & MC13783_ADC_16CHANS) + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans); +out_err_create_16chans: + + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base); + return ret; +} + +static int mc13783_adc_remove(struct platform_device *pdev) +{ + struct mc13783_adc_priv *priv = platform_get_drvdata(pdev); + kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data; + + hwmon_device_unregister(priv->hwmon_dev); + + if (!mc13783_adc_use_touchscreen(pdev)) + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts); + + if (driver_data & MC13783_ADC_16CHANS) + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans); + + sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base); + + return 0; +} + +static const struct platform_device_id mc13783_adc_idtable[] = { + { + .name = "mc13783-adc", + .driver_data = MC13783_ADC_16CHANS, + }, { + .name = "mc13892-adc", + .driver_data = MC13783_ADC_BPDIV2, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(platform, mc13783_adc_idtable); + +static struct platform_driver mc13783_adc_driver = { + .remove = mc13783_adc_remove, + .driver = { + .name = DRIVER_NAME, + }, + .id_table = mc13783_adc_idtable, +}; + +module_platform_driver_probe(mc13783_adc_driver, mc13783_adc_probe); + +MODULE_DESCRIPTION("MC13783 ADC driver"); +MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>"); +MODULE_LICENSE("GPL"); |