+++ /dev/null
-/*
- * AD7150 capacitive sensor driver supporting AD7150/1/6
- *
- * Copyright 2010-2011 Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
-
-#include <linux/interrupt.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/i2c.h>
-#include <linux/module.h>
-
-#include "../iio.h"
-#include "../sysfs.h"
-
-/*
- * AD7150 registers definition
- */
-
-#define AD7150_STATUS 0
-#define AD7150_STATUS_OUT1 (1 << 3)
-#define AD7150_STATUS_OUT2 (1 << 5)
-#define AD7150_CH1_DATA_HIGH 1
-#define AD7150_CH2_DATA_HIGH 3
-#define AD7150_CH1_AVG_HIGH 5
-#define AD7150_CH2_AVG_HIGH 7
-#define AD7150_CH1_SENSITIVITY 9
-#define AD7150_CH1_THR_HOLD_H 9
-#define AD7150_CH1_TIMEOUT 10
-#define AD7150_CH1_SETUP 11
-#define AD7150_CH2_SENSITIVITY 12
-#define AD7150_CH2_THR_HOLD_H 12
-#define AD7150_CH2_TIMEOUT 13
-#define AD7150_CH2_SETUP 14
-#define AD7150_CFG 15
-#define AD7150_CFG_FIX (1 << 7)
-#define AD7150_PD_TIMER 16
-#define AD7150_CH1_CAPDAC 17
-#define AD7150_CH2_CAPDAC 18
-#define AD7150_SN3 19
-#define AD7150_SN2 20
-#define AD7150_SN1 21
-#define AD7150_SN0 22
-#define AD7150_ID 23
-
-/**
- * struct ad7150_chip_info - instance specific chip data
- * @client: i2c client for this device
- * @current_event: device always has one type of event enabled.
- * This element stores the event code of the current one.
- * @threshold: thresholds for simple capacitance value events
- * @thresh_sensitivity: threshold for simple capacitance offset
- * from 'average' value.
- * @mag_sensitity: threshold for magnitude of capacitance offset from
- * from 'average' value.
- * @thresh_timeout: a timeout, in samples from the moment an
- * adaptive threshold event occurs to when the average
- * value jumps to current value.
- * @mag_timeout: a timeout, in sample from the moment an
- * adaptive magnitude event occurs to when the average
- * value jumps to the current value.
- * @old_state: store state from previous event, allowing confirmation
- * of new condition.
- * @conversion_mode: the current conversion mode.
- * @state_lock: ensure consistent state of this structure wrt the
- * hardware.
- */
-struct ad7150_chip_info {
- struct i2c_client *client;
- u64 current_event;
- u16 threshold[2][2];
- u8 thresh_sensitivity[2][2];
- u8 mag_sensitivity[2][2];
- u8 thresh_timeout[2][2];
- u8 mag_timeout[2][2];
- int old_state;
- char *conversion_mode;
- struct mutex state_lock;
-};
-
-/*
- * sysfs nodes
- */
-
-static const u8 ad7150_addresses[][6] = {
- { AD7150_CH1_DATA_HIGH, AD7150_CH1_AVG_HIGH,
- AD7150_CH1_SETUP, AD7150_CH1_THR_HOLD_H,
- AD7150_CH1_SENSITIVITY, AD7150_CH1_TIMEOUT },
- { AD7150_CH2_DATA_HIGH, AD7150_CH2_AVG_HIGH,
- AD7150_CH2_SETUP, AD7150_CH2_THR_HOLD_H,
- AD7150_CH2_SENSITIVITY, AD7150_CH2_TIMEOUT },
-};
-
-static int ad7150_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val,
- int *val2,
- long mask)
-{
- int ret;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
-
- switch (mask) {
- case 0:
- ret = i2c_smbus_read_word_data(chip->client,
- ad7150_addresses[chan->channel][0]);
- if (ret < 0)
- return ret;
- *val = swab16(ret);
- return IIO_VAL_INT;
- case (1 << IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE):
- ret = i2c_smbus_read_word_data(chip->client,
- ad7150_addresses[chan->channel][1]);
- if (ret < 0)
- return ret;
- *val = swab16(ret);
- return IIO_VAL_INT;
- default:
- return -EINVAL;
- }
-}
-
-static int ad7150_read_event_config(struct iio_dev *indio_dev, u64 event_code)
-{
- int ret;
- u8 threshtype;
- bool adaptive;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
- IIO_EV_DIR_RISING);
-
- ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
- if (ret < 0)
- return ret;
-
- threshtype = (ret >> 5) & 0x03;
- adaptive = !!(ret & 0x80);
-
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- if (rising)
- return adaptive && (threshtype == 0x1);
- else
- return adaptive && (threshtype == 0x0);
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- if (rising)
- return adaptive && (threshtype == 0x3);
- else
- return adaptive && (threshtype == 0x2);
-
- case IIO_EV_TYPE_THRESH:
- if (rising)
- return !adaptive && (threshtype == 0x1);
- else
- return !adaptive && (threshtype == 0x0);
- };
- return -EINVAL;
-}
-
-/* lock should be held */
-static int ad7150_write_event_params(struct iio_dev *indio_dev, u64 event_code)
-{
- int ret;
- u16 value;
- u8 sens, timeout;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- int chan = IIO_EVENT_CODE_EXTRACT_NUM(event_code);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
- IIO_EV_DIR_RISING);
-
- if (event_code != chip->current_event)
- return 0;
-
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
- /* Note completely different from the adaptive versions */
- case IIO_EV_TYPE_THRESH:
- value = chip->threshold[rising][chan];
- ret = i2c_smbus_write_word_data(chip->client,
- ad7150_addresses[chan][3],
- swab16(value));
- if (ret < 0)
- return ret;
- return 0;
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- sens = chip->mag_sensitivity[rising][chan];
- timeout = chip->mag_timeout[rising][chan];
- break;
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- sens = chip->thresh_sensitivity[rising][chan];
- timeout = chip->thresh_timeout[rising][chan];
- break;
- default:
- return -EINVAL;
- };
- ret = i2c_smbus_write_byte_data(chip->client,
- ad7150_addresses[chan][4],
- sens);
- if (ret < 0)
- return ret;
-
- ret = i2c_smbus_write_byte_data(chip->client,
- ad7150_addresses[chan][5],
- timeout);
- if (ret < 0)
- return ret;
-
- return 0;
-}
-
-static int ad7150_write_event_config(struct iio_dev *indio_dev,
- u64 event_code, int state)
-{
- u8 thresh_type, cfg, adaptive;
- int ret;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
- IIO_EV_DIR_RISING);
-
- /* Something must always be turned on */
- if (state == 0)
- return -EINVAL;
-
- if (event_code == chip->current_event)
- return 0;
- mutex_lock(&chip->state_lock);
- ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
- if (ret < 0)
- goto error_ret;
-
- cfg = ret & ~((0x03 << 5) | (0x1 << 7));
-
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- adaptive = 1;
- if (rising)
- thresh_type = 0x1;
- else
- thresh_type = 0x0;
- break;
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- adaptive = 1;
- if (rising)
- thresh_type = 0x3;
- else
- thresh_type = 0x2;
- break;
- case IIO_EV_TYPE_THRESH:
- adaptive = 0;
- if (rising)
- thresh_type = 0x1;
- else
- thresh_type = 0x0;
- break;
- default:
- ret = -EINVAL;
- goto error_ret;
- };
-
- cfg |= (!adaptive << 7) | (thresh_type << 5);
-
- ret = i2c_smbus_write_byte_data(chip->client, AD7150_CFG, cfg);
- if (ret < 0)
- goto error_ret;
-
- chip->current_event = event_code;
-
- /* update control attributes */
- ret = ad7150_write_event_params(indio_dev, event_code);
-error_ret:
- mutex_unlock(&chip->state_lock);
-
- return 0;
-}
-
-static int ad7150_read_event_value(struct iio_dev *indio_dev,
- u64 event_code,
- int *val)
-{
- int chan = IIO_EVENT_CODE_EXTRACT_NUM(event_code);
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
- IIO_EV_DIR_RISING);
-
- /* Complex register sharing going on here */
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- *val = chip->mag_sensitivity[rising][chan];
- return 0;
-
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- *val = chip->thresh_sensitivity[rising][chan];
- return 0;
-
- case IIO_EV_TYPE_THRESH:
- *val = chip->threshold[rising][chan];
- return 0;
-
- default:
- return -EINVAL;
- };
-}
-
-static int ad7150_write_event_value(struct iio_dev *indio_dev,
- u64 event_code,
- int val)
-{
- int ret;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- int chan = IIO_EVENT_CODE_EXTRACT_NUM(event_code);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
- IIO_EV_DIR_RISING);
-
- mutex_lock(&chip->state_lock);
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- chip->mag_sensitivity[rising][chan] = val;
- break;
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- chip->thresh_sensitivity[rising][chan] = val;
- break;
- case IIO_EV_TYPE_THRESH:
- chip->threshold[rising][chan] = val;
- break;
- default:
- ret = -EINVAL;
- goto error_ret;
- };
-
- /* write back if active */
- ret = ad7150_write_event_params(indio_dev, event_code);
-
-error_ret:
- mutex_unlock(&chip->state_lock);
- return ret;
-}
-
-static ssize_t ad7150_show_timeout(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *indio_dev = dev_get_drvdata(dev);
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- u8 value;
-
- /* use the event code for consistency reasons */
- int chan = IIO_EVENT_CODE_EXTRACT_NUM(this_attr->address);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(this_attr->address)
- == IIO_EV_DIR_RISING);
-
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(this_attr->address)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- value = chip->mag_timeout[rising][chan];
- break;
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- value = chip->thresh_timeout[rising][chan];
- break;
- default:
- return -EINVAL;
- };
-
- return sprintf(buf, "%d\n", value);
-}
-
-static ssize_t ad7150_store_timeout(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *indio_dev = dev_get_drvdata(dev);
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- int chan = IIO_EVENT_CODE_EXTRACT_NUM(this_attr->address);
- int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(this_attr->address) ==
- IIO_EV_DIR_RISING);
- u8 data;
- int ret;
-
- ret = kstrtou8(buf, 10, &data);
- if (ret < 0)
- return ret;
-
- mutex_lock(&chip->state_lock);
- switch (IIO_EVENT_CODE_EXTRACT_TYPE(this_attr->address)) {
- case IIO_EV_TYPE_MAG_ADAPTIVE:
- chip->mag_timeout[rising][chan] = data;
- break;
- case IIO_EV_TYPE_THRESH_ADAPTIVE:
- chip->thresh_timeout[rising][chan] = data;
- break;
- default:
- ret = -EINVAL;
- goto error_ret;
- };
-
- ret = ad7150_write_event_params(indio_dev, this_attr->address);
-error_ret:
- mutex_unlock(&chip->state_lock);
-
- if (ret < 0)
- return ret;
-
- return len;
-}
-
-#define AD7150_TIMEOUT(chan, type, dir, ev_type, ev_dir) \
- IIO_DEVICE_ATTR(in_capacitance##chan##_##type##_##dir##_timeout, \
- S_IRUGO | S_IWUSR, \
- &ad7150_show_timeout, \
- &ad7150_store_timeout, \
- IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE, \
- chan, \
- IIO_EV_TYPE_##ev_type, \
- IIO_EV_DIR_##ev_dir))
-static AD7150_TIMEOUT(0, mag_adaptive, rising, MAG_ADAPTIVE, RISING);
-static AD7150_TIMEOUT(0, mag_adaptive, falling, MAG_ADAPTIVE, FALLING);
-static AD7150_TIMEOUT(1, mag_adaptive, rising, MAG_ADAPTIVE, RISING);
-static AD7150_TIMEOUT(1, mag_adaptive, falling, MAG_ADAPTIVE, FALLING);
-static AD7150_TIMEOUT(0, thresh_adaptive, rising, THRESH_ADAPTIVE, RISING);
-static AD7150_TIMEOUT(0, thresh_adaptive, falling, THRESH_ADAPTIVE, FALLING);
-static AD7150_TIMEOUT(1, thresh_adaptive, rising, THRESH_ADAPTIVE, RISING);
-static AD7150_TIMEOUT(1, thresh_adaptive, falling, THRESH_ADAPTIVE, FALLING);
-
-static const struct iio_chan_spec ad7150_channels[] = {
- {
- .type = IIO_CAPACITANCE,
- .indexed = 1,
- .channel = 0,
- .info_mask = (1 << IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE),
- .event_mask =
- IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH_ADAPTIVE, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH_ADAPTIVE, IIO_EV_DIR_FALLING) |
- IIO_EV_BIT(IIO_EV_TYPE_MAG_ADAPTIVE, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_MAG_ADAPTIVE, IIO_EV_DIR_FALLING)
- }, {
- .type = IIO_CAPACITANCE,
- .indexed = 1,
- .channel = 1,
- .info_mask = (1 << IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE),
- .event_mask =
- IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH_ADAPTIVE, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_THRESH_ADAPTIVE, IIO_EV_DIR_FALLING) |
- IIO_EV_BIT(IIO_EV_TYPE_MAG_ADAPTIVE, IIO_EV_DIR_RISING) |
- IIO_EV_BIT(IIO_EV_TYPE_MAG_ADAPTIVE, IIO_EV_DIR_FALLING)
- },
-};
-
-/*
- * threshold events
- */
-
-static irqreturn_t ad7150_event_handler(int irq, void *private)
-{
- struct iio_dev *indio_dev = private;
- struct ad7150_chip_info *chip = iio_priv(indio_dev);
- u8 int_status;
- s64 timestamp = iio_get_time_ns();
- int ret;
-
- ret = i2c_smbus_read_byte_data(chip->client, AD7150_STATUS);
- if (ret < 0)
- return IRQ_HANDLED;
-
- int_status = ret;
-
- if ((int_status & AD7150_STATUS_OUT1) &&
- !(chip->old_state & AD7150_STATUS_OUT1))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
- 0,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_RISING),
- timestamp);
- else if ((!(int_status & AD7150_STATUS_OUT1)) &&
- (chip->old_state & AD7150_STATUS_OUT1))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
- 0,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_FALLING),
- timestamp);
-
- if ((int_status & AD7150_STATUS_OUT2) &&
- !(chip->old_state & AD7150_STATUS_OUT2))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
- 1,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_RISING),
- timestamp);
- else if ((!(int_status & AD7150_STATUS_OUT2)) &&
- (chip->old_state & AD7150_STATUS_OUT2))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
- 1,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_FALLING),
- timestamp);
- /* store the status to avoid repushing same events */
- chip->old_state = int_status;
-
- return IRQ_HANDLED;
-}
-
-/* Timeouts not currently handled by core */
-static struct attribute *ad7150_event_attributes[] = {
- &iio_dev_attr_in_capacitance0_mag_adaptive_rising_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance0_mag_adaptive_falling_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance1_mag_adaptive_rising_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance1_mag_adaptive_falling_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance0_thresh_adaptive_rising_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance0_thresh_adaptive_falling_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance1_thresh_adaptive_rising_timeout
- .dev_attr.attr,
- &iio_dev_attr_in_capacitance1_thresh_adaptive_falling_timeout
- .dev_attr.attr,
- NULL,
-};
-
-static struct attribute_group ad7150_event_attribute_group = {
- .attrs = ad7150_event_attributes,
- .name = "events",
-};
-
-static const struct iio_info ad7150_info = {
- .event_attrs = &ad7150_event_attribute_group,
- .driver_module = THIS_MODULE,
- .read_raw = &ad7150_read_raw,
- .read_event_config = &ad7150_read_event_config,
- .write_event_config = &ad7150_write_event_config,
- .read_event_value = &ad7150_read_event_value,
- .write_event_value = &ad7150_write_event_value,
-};
-
-/*
- * device probe and remove
- */
-
-static int __devinit ad7150_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
-{
- int ret;
- struct ad7150_chip_info *chip;
- struct iio_dev *indio_dev;
-
- indio_dev = iio_allocate_device(sizeof(*chip));
- if (indio_dev == NULL) {
- ret = -ENOMEM;
- goto error_ret;
- }
- chip = iio_priv(indio_dev);
- mutex_init(&chip->state_lock);
- /* this is only used for device removal purposes */
- i2c_set_clientdata(client, indio_dev);
-
- chip->client = client;
-
- indio_dev->name = id->name;
- indio_dev->channels = ad7150_channels;
- indio_dev->num_channels = ARRAY_SIZE(ad7150_channels);
- /* Establish that the iio_dev is a child of the i2c device */
- indio_dev->dev.parent = &client->dev;
-
- indio_dev->info = &ad7150_info;
-
- indio_dev->modes = INDIO_DIRECT_MODE;
-
- if (client->irq) {
- ret = request_threaded_irq(client->irq,
- NULL,
- &ad7150_event_handler,
- IRQF_TRIGGER_RISING |
- IRQF_TRIGGER_FALLING,
- "ad7150_irq1",
- indio_dev);
- if (ret)
- goto error_free_dev;
- }
-
- if (client->dev.platform_data) {
- ret = request_threaded_irq(*(unsigned int *)
- client->dev.platform_data,
- NULL,
- &ad7150_event_handler,
- IRQF_TRIGGER_RISING |
- IRQF_TRIGGER_FALLING,
- "ad7150_irq2",
- indio_dev);
- if (ret)
- goto error_free_irq;
- }
-
- ret = iio_device_register(indio_dev);
- if (ret)
- goto error_free_irq2;
-
- dev_info(&client->dev, "%s capacitive sensor registered,irq: %d\n",
- id->name, client->irq);
-
- return 0;
-error_free_irq2:
- if (client->dev.platform_data)
- free_irq(*(unsigned int *)client->dev.platform_data,
- indio_dev);
-error_free_irq:
- if (client->irq)
- free_irq(client->irq, indio_dev);
-error_free_dev:
- iio_free_device(indio_dev);
-error_ret:
- return ret;
-}
-
-static int __devexit ad7150_remove(struct i2c_client *client)
-{
- struct iio_dev *indio_dev = i2c_get_clientdata(client);
-
- iio_device_unregister(indio_dev);
- if (client->irq)
- free_irq(client->irq, indio_dev);
-
- if (client->dev.platform_data)
- free_irq(*(unsigned int *)client->dev.platform_data, indio_dev);
-
- iio_free_device(indio_dev);
-
- return 0;
-}
-
-static const struct i2c_device_id ad7150_id[] = {
- { "ad7150", 0 },
- { "ad7151", 0 },
- { "ad7156", 0 },
- {}
-};
-
-MODULE_DEVICE_TABLE(i2c, ad7150_id);
-
-static struct i2c_driver ad7150_driver = {
- .driver = {
- .name = "ad7150",
- },
- .probe = ad7150_probe,
- .remove = __devexit_p(ad7150_remove),
- .id_table = ad7150_id,
-};
-
-static __init int ad7150_init(void)
-{
- return i2c_add_driver(&ad7150_driver);
-}
-
-static __exit void ad7150_exit(void)
-{
- i2c_del_driver(&ad7150_driver);
-}
-
-MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
-MODULE_DESCRIPTION("Analog Devices AD7150/1/6 capacitive sensor driver");
-MODULE_LICENSE("GPL v2");
-
-module_init(ad7150_init);
-module_exit(ad7150_exit);
git.openpandora.org / pandora-kernel.git / blobdiff