On 04/03/17 17:53, Jonathan Cameron wrote: > On 02/03/17 18:40, Manivannan Sadhasivam wrote: >> This patch adds support for STMicro VL6180 - ALS and proximity sensor. Sensor is capable of measuring the light >> intensity as well as object distance using TOF(Time of Flight) technology. >> >> Signed-off-by: Manivannan Sadhasivam <manivannanece23@xxxxxxxxx> > Few more comments from me. One more thing (from browsing datasheet). I would have expected to see some control of the gpios as it seems to have a very explicit start up sequence described. Is this something you are doing some other way? Jonathan > > Jonathan >> --- >> .../devicetree/bindings/iio/light/vl6180.txt | 16 + >> drivers/iio/light/Kconfig | 10 + >> drivers/iio/light/Makefile | 1 + >> drivers/iio/light/vl6180.c | 544 +++++++++++++++++++++ >> 4 files changed, 571 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/iio/light/vl6180.txt >> create mode 100644 drivers/iio/light/vl6180.c >> >> diff --git a/Documentation/devicetree/bindings/iio/light/vl6180.txt b/Documentation/devicetree/bindings/iio/light/vl6180.txt >> new file mode 100644 >> index 0000000..bc1820a >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/iio/light/vl6180.txt >> @@ -0,0 +1,16 @@ >> +STMicro VL6180 - ALS and proximity sensor >> + >> +Link to datasheet: http://www.st.com/resource/en/datasheet/vl6180x.pdf >> + >> +Required properties: >> + >> + -compatible: should be "st,vl6180" >> + -reg: the I2C address of the sensor >> + >> +Example: >> + >> +vl6180@29 { >> + compatible = "st,vl6180"; >> + reg = <0x29>; >> +}; >> + >> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig >> index 7c566f5..c26113a 100644 >> --- a/drivers/iio/light/Kconfig >> +++ b/drivers/iio/light/Kconfig >> @@ -352,4 +352,14 @@ config VEML6070 >> To compile this driver as a module, choose M here: the >> module will be called veml6070. >> >> +config VL6180 >> + tristate "VL6180 ALS and proximity sensor" >> + depends on I2C >> + help >> + Say Y here if you want to build a driver for the STMicroelectronics >> + VL6180 combined ambient light and proximity sensor. >> + >> + To compile this driver as a module, choose M here: the >> + module will be called vl6180. >> + >> endmenu >> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile >> index 6f2a3c6..24a8d72 100644 >> --- a/drivers/iio/light/Makefile >> +++ b/drivers/iio/light/Makefile >> @@ -33,3 +33,4 @@ obj-$(CONFIG_TSL4531) += tsl4531.o >> obj-$(CONFIG_US5182D) += us5182d.o >> obj-$(CONFIG_VCNL4000) += vcnl4000.o >> obj-$(CONFIG_VEML6070) += veml6070.o >> +obj-$(CONFIG_VL6180) += vl6180.o >> diff --git a/drivers/iio/light/vl6180.c b/drivers/iio/light/vl6180.c >> new file mode 100644 >> index 0000000..de80d96 >> --- /dev/null >> +++ b/drivers/iio/light/vl6180.c >> @@ -0,0 +1,544 @@ >> +/* >> + * vl6180.c - Support for STMicroelectronics VL6180 ALS and proximity sensor >> + * >> + * Copyright 2017 Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx> >> + * Copyright 2017 Manivannan Sadhasivam <manivannanece23@xxxxxxxxx> >> + * >> + * This file is subject to the terms and conditions of version 2 of >> + * the GNU General Public License. See the file COPYING in the main >> + * directory of this archive for more details. >> + * >> + * IIO driver for VL6180 (7-bit I2C slave addresses 0x29) >> + * >> + * Range: 0 to 100mm >> + * ALS: < 1 Lux up to 100 kLux >> + * IR: 850nm >> + * >> + * TODO: irq, threshold events, continuous mode, hardware buffer >> + */ >> + >> +#include <linux/module.h> >> +#include <linux/i2c.h> >> +#include <linux/mutex.h> >> +#include <linux/err.h> >> +#include <linux/of.h> >> +#include <linux/delay.h> >> + >> +#include <linux/iio/iio.h> >> +#include <linux/iio/sysfs.h> >> + >> +#define VL6180_DRV_NAME "vl6180" >> + >> +/* Device identification register and value */ >> +#define VL6180_MODEL_ID 0x000 >> +#define VL6180_MODEL_ID_VAL 0xb4 >> + >> +/* Configuration registers */ >> +#define VL6180_INTR_CONFIG 0x014 >> +#define VL6180_INTR_CLEAR 0x015 >> +#define VL6180_OUT_OF_RESET 0x016 >> +#define VL6180_HOLD 0x017 >> +#define VL6180_RANGE_START 0x018 >> +#define VL6180_ALS_START 0x038 >> +#define VL6180_ALS_GAIN 0x03f >> +#define VL6180_ALS_IT 0x040 >> + >> +/* Status registers */ >> +#define VL6180_RANGE_STATUS 0x04d >> +#define VL6180_ALS_STATUS 0x04e >> +#define VL6180_INTR_STATUS 0x04f >> + >> +/* Result value registers */ >> +#define VL6180_ALS_VALUE 0x050 >> +#define VL6180_RANGE_VALUE 0x062 >> +#define VL6180_RANGE_RATE 0x066 >> + >> +/* bits of the RANGE_START and ALS_START register */ >> +#define VL6180_MODE_CONT BIT(1) /* continuous mode */ >> +#define VL6180_STARTSTOP BIT(0) /* start measurement, auto-reset */ >> + >> +/* bits of the INTR_STATUS and INTR_CONFIG register */ >> +#define VL6180_ALS_READY BIT(5) >> +#define VL6180_RANGE_READY BIT(2) >> + >> +/* bits of the INTR_CLEAR register */ >> +#define VL6180_CLEAR_ERROR BIT(2) >> +#define VL6180_CLEAR_ALS BIT(1) >> +#define VL6180_CLEAR_RANGE BIT(0) >> + >> +/* bits of the HOLD register */ >> +#define VL6180_HOLD_ON BIT(0) >> + >> +/* default value for the ALS_IT register */ >> +#define VL6180_ALS_IT_100 0x063 /* 100 ms */ >> + >> +/* values for the ALS_GAIN register */ >> +#define VL6180_ALS_GAIN_1 0x46 >> +#define VL6180_ALS_GAIN_1_25 0x45 >> +#define VL6180_ALS_GAIN_1_67 0x44 >> +#define VL6180_ALS_GAIN_2_5 0x43 >> +#define VL6180_ALS_GAIN_5 0x42 >> +#define VL6180_ALS_GAIN_10 0x41 >> +#define VL6180_ALS_GAIN_20 0x40 >> +#define VL6180_ALS_GAIN_40 0x47 >> + >> +struct vl6180_data { >> + struct i2c_client *client; >> + struct mutex lock; >> +}; >> + >> +enum { VL6180_ALS, VL6180_RANGE, VL6180_PROX }; >> + >> +/** >> + * struct vl6180_chan_regs - Registers for accessing channels >> + * @drdy_mask: Data ready bits in status register >> + * @start_reg: Conversion start registeir >> + * @value_reg: Result value register >> + */ >> +struct vl6180_chan_regs { >> + u8 drdy_mask; >> + u16 start_reg, value_reg; >> + bool word; >> +}; >> + >> +static const struct vl6180_chan_regs vl6180_chan_regs_table[] = { >> + [VL6180_ALS] = { >> + .drdy_mask = VL6180_ALS_READY, >> + .start_reg = VL6180_ALS_START, >> + .value_reg = VL6180_ALS_VALUE, >> + .word = true, >> + }, >> + [VL6180_RANGE] = { >> + .drdy_mask = VL6180_RANGE_READY, >> + .start_reg = VL6180_RANGE_START, >> + .value_reg = VL6180_RANGE_VALUE, >> + .word = false, >> + }, >> + [VL6180_PROX] = { >> + .drdy_mask = VL6180_RANGE_READY, >> + .start_reg = VL6180_RANGE_START, >> + .value_reg = VL6180_RANGE_RATE, >> + .word = true, >> + }, >> +}; >> + >> +static int vl6180_read(struct i2c_client *client, u16 cmd, void *databuf, >> + u8 len) >> +{ >> + u16 cmdbuf = cpu_to_be16(cmd); >> + struct i2c_msg msgs[2] = { >> + { .addr = client->addr, .len = 2, .buf = (u8 *) &cmdbuf }, >> + { .addr = client->addr, .len = len, .buf = databuf, >> + .flags = I2C_M_RD } }; >> + int ret; > Hmm. could wrap this up in regmap rather neatly I think, but fair enough > to keep it all obvious here if you prefer. >> + >> + ret = i2c_transfer(client->adapter, msgs, 2); >> + if (ret < 0) >> + dev_err(&client->dev, "failed reading register 0x%04x\n", cmd); >> + >> + return ret; >> +} >> + >> +static int vl6180_read_byte(struct i2c_client *client, u16 cmd) >> +{ >> + u8 data; >> + int ret; >> + >> + ret = vl6180_read(client, cmd, &data, sizeof(data)); >> + if (ret < 0) >> + return ret; >> + >> + return data; >> +} >> + >> +static int vl6180_read_word(struct i2c_client *client, u16 cmd) >> +{ >> + __be16 data; >> + int ret; >> + >> + ret = vl6180_read(client, cmd, &data, sizeof(data)); >> + if (ret < 0) >> + return ret; >> + >> + return be16_to_cpu(data); >> +} >> + >> +static int vl6180_write_byte(struct i2c_client *client, u16 cmd, u8 val) >> +{ >> + u8 buf[3]; >> + struct i2c_msg msgs[1] = { >> + { .addr = client->addr, .len = 3, .buf = buf } }; >> + int ret; >> + >> + buf[0] = cmd >> 8; >> + buf[1] = cmd & 0xff; > Here you end up with a mix that makes it harder to force the endianness than > below, but it can still be done by using cpu_to_be16p and again makes > that conversion explicit. >> + buf[2] = val; >> + >> + ret = i2c_transfer(client->adapter, msgs, 1); >> + if (ret < 0) { >> + dev_err(&client->dev, "failed writing register 0x%04x\n", cmd); >> + return ret; >> + } >> + >> + return 0; >> +} >> + >> +static int vl6180_write_word(struct i2c_client *client, u16 cmd, u16 val) >> +{ >> + u8 buf[4]; >> + struct i2c_msg msgs[1] = { >> + { .addr = client->addr, .len = 4, .buf = buf } }; >> + int ret; >> + >> + buf[0] = cmd >> 8; >> + buf[1] = cmd & 0xff; > Could be done 'slightly' more efficiently by using the fact these are clearly > u16s. Then in the case where the system is of the same endianness these > become simple copies. cpu_to_be16 should do the trick (assuming I've got > the write one;) > > Make buf __be16 and this becomes explicit in the code which is always a > nice bonus. >> + buf[2] = val >> 8; >> + buf[3] = val & 0xff; >> + >> + ret = i2c_transfer(client->adapter, msgs, 1); >> + if (ret < 0) { >> + dev_err(&client->dev, "failed writing register 0x%04x\n", cmd); >> + return ret; >> + } >> + >> + return 0; >> +} >> + >> +static int vl6180_measure(struct vl6180_data *data, int addr) >> +{ >> + struct i2c_client *client = data->client; >> + int tries = 20, ret; >> + u16 value; >> + >> + mutex_lock(&data->lock); >> + /* Start single shot measurement */ >> + ret = vl6180_write_byte(client, >> + vl6180_chan_regs_table[addr].start_reg, VL6180_STARTSTOP); >> + if (ret < 0) >> + goto fail; >> + >> + while (tries--) { >> + ret = vl6180_read_byte(client, VL6180_INTR_STATUS); >> + if (ret < 0) >> + goto fail; >> + >> + if (ret & vl6180_chan_regs_table[addr].drdy_mask) >> + break; >> + msleep(20); > Presumably we can know approximately how long this is going to take depending > on state and perhaps reduce the bus traffic by guessing 'about' right. >> + } >> + >> + if (tries < 0) { >> + ret = -EIO; >> + goto fail; >> + } >> + >> + /* Read result value from appropriate registers */ >> + ret = vl6180_chan_regs_table[addr].word ? >> + vl6180_read_word(client, vl6180_chan_regs_table[addr].value_reg) : >> + vl6180_read_byte(client, vl6180_chan_regs_table[addr].value_reg); >> + if (ret < 0) >> + goto fail; >> + value = ret; >> + >> + /* Clear the interrupt flag after data read */ >> + ret = vl6180_write_byte(client, VL6180_INTR_CLEAR, >> + VL6180_CLEAR_ERROR | VL6180_CLEAR_ALS | VL6180_CLEAR_RANGE); >> + if (ret < 0) >> + goto fail; >> + >> + ret = value; >> + >> +fail: >> + mutex_unlock(&data->lock); >> + >> + return ret; >> +} >> + >> +static const struct iio_chan_spec vl6180_channels[] = { >> + { >> + .type = IIO_LIGHT, >> + .address = VL6180_ALS, >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | >> + BIT(IIO_CHAN_INFO_INT_TIME) | >> + BIT(IIO_CHAN_INFO_SCALE) | >> + BIT(IIO_CHAN_INFO_HARDWAREGAIN), >> + }, { >> + .type = IIO_DISTANCE, >> + .address = VL6180_RANGE, >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | >> + BIT(IIO_CHAN_INFO_SCALE), >> + }, { >> + .type = IIO_PROXIMITY, >> + .address = VL6180_PROX, >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), >> + } >> +}; >> + > As Peter raised, not that obvious what these are. Please add a comment > explaining. >> +static const int vl6180_als_gain[8][4] = { >> + { 1, 0, 70, VL6180_ALS_GAIN_1 }, >> + { 1, 250000, 69, VL6180_ALS_GAIN_1_25 }, >> + { 1, 670000, 68, VL6180_ALS_GAIN_1_67 }, >> + { 2, 500000, 67, VL6180_ALS_GAIN_2_5 }, >> + { 5, 0, 66, VL6180_ALS_GAIN_5 }, >> + { 10, 0, 65, VL6180_ALS_GAIN_10 }, >> + { 20, 0, 64, VL6180_ALS_GAIN_20 }, >> + { 40, 0, 71, VL6180_ALS_GAIN_40 } >> +}; >> + >> + >> +static int vl6180_read_raw(struct iio_dev *indio_dev, >> + struct iio_chan_spec const *chan, >> + int *val, int *val2, long mask) >> +{ >> + struct vl6180_data *data = iio_priv(indio_dev); >> + int ret, i; >> + >> + switch (mask) { >> + case IIO_CHAN_INFO_RAW: >> + ret = vl6180_measure(data, chan->address); >> + if (ret < 0) >> + return ret; >> + *val = ret; >> + >> + return IIO_VAL_INT; >> + case IIO_CHAN_INFO_INT_TIME: >> + ret = vl6180_read_word(data->client, VL6180_ALS_IT); >> + if (ret < 0) >> + return ret; >> + *val = 0; /* 1 count = 1ms (0 = 1ms) */ >> + *val2 = (ret + 1) * 1000; /* convert to seconds */ >> + >> + return IIO_VAL_INT_PLUS_MICRO; >> + case IIO_CHAN_INFO_SCALE: >> + switch (chan->type) { >> + case IIO_LIGHT: >> + *val = 0; /* one ALS count is 0.32 Lux */ >> + *val2 = 320000; >> + break; >> + case IIO_DISTANCE: >> + *val = 0; /* sensor reports mm, scale to meter */ >> + *val2 = 1000; >> + break; >> + default: >> + return -EINVAL; >> + } >> + >> + return IIO_VAL_INT_PLUS_MICRO; >> + case IIO_CHAN_INFO_HARDWAREGAIN: >> + ret = vl6180_read_byte(data->client, VL6180_ALS_GAIN); >> + if (ret < 0) >> + return -EINVAL; >> + for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) { >> + if (ret == vl6180_als_gain[i][2]) { >> + *val = vl6180_als_gain[i][0]; >> + *val2 = vl6180_als_gain[i][1]; >> + } >> + } >> + >> + return IIO_VAL_INT_PLUS_MICRO; >> + default: >> + return -EINVAL; >> + } >> +} >> + >> +static IIO_CONST_ATTR(als_gain_available, "1 1.25 1.67 2.5 5 10 20 40"); >> + >> +static struct attribute *vl6180_attributes[] = { >> + &iio_const_attr_als_gain_available.dev_attr.attr, >> + NULL >> +}; >> + >> +static const struct attribute_group vl6180_attribute_group = { >> + .attrs = vl6180_attributes, >> +}; >> + >> +/* HOLD is needed before updading any config registers */ >> +static int vl6180_hold(struct vl6180_data *data, bool hold) >> +{ >> + return vl6180_write_byte(data->client, VL6180_HOLD, >> + hold ? VL6180_HOLD_ON : 0); >> +} >> + >> +static int vl6180_set_als_gain(struct vl6180_data *data, int val, int val2) >> +{ >> + int i, ret; >> + >> + for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) { >> + if (val == vl6180_als_gain[i][0] && >> + val2 == vl6180_als_gain[i][1]) { >> + mutex_lock(&data->lock); >> + ret = vl6180_hold(data, true); >> + if (ret < 0) >> + goto fail; >> + ret = vl6180_write_byte(data->client, VL6180_ALS_GAIN, >> + vl6180_als_gain[i][3]); >> +fail: >> + vl6180_hold(data, false); >> + mutex_unlock(&data->lock); >> + return ret; >> + } >> + } >> + >> + return -EINVAL; >> +} >> + >> +static int vl6180_set_it(struct vl6180_data *data, int val2) >> +{ >> + int ret; >> + >> + mutex_lock(&data->lock); >> + ret = vl6180_hold(data, true); >> + if (ret < 0) >> + goto fail; >> + ret = vl6180_write_word(data->client, VL6180_ALS_IT, >> + (val2 - 500) / 1000); /* write value in ms */ >> +fail: >> + vl6180_hold(data, false); >> + mutex_unlock(&data->lock); >> + >> + return ret; >> +} >> + >> +static int vl6180_write_raw(struct iio_dev *indio_dev, >> + struct iio_chan_spec const *chan, >> + int val, int val2, long mask) >> +{ >> + struct vl6180_data *data = iio_priv(indio_dev); >> + >> + switch (mask) { >> + case IIO_CHAN_INFO_INT_TIME: >> + if (val != 0 || val2 < 500 || val2 >= 512500) >> + return -EINVAL; >> + >> + return vl6180_set_it(data, val2); >> + case IIO_CHAN_INFO_HARDWAREGAIN: >> + if (chan->type != IIO_LIGHT) >> + return -EINVAL; >> + >> + return vl6180_set_als_gain(data, val, val2); >> + default: >> + return -EINVAL; >> + } >> +} >> + >> +static const struct iio_info vl6180_info = { >> + .read_raw = vl6180_read_raw, >> + .write_raw = vl6180_write_raw, >> + .attrs = &vl6180_attribute_group, >> + .driver_module = THIS_MODULE, >> +}; >> + >> +/** >> + * Following settings are enabled: >> + * 1. ALS and Range ready interrupts > I'd prefer to see these comments next to the place they are implemented. > Much less likely to end up out of date there. >> + * 2. ALS integration time: 100ms >> + * 3. ALS gain: 1 >> + */ >> +static int vl6180_init(struct vl6180_data *data) >> +{ >> + struct i2c_client *client = data->client; >> + int ret; >> + >> + ret = vl6180_read_byte(client, VL6180_MODEL_ID); >> + if (ret < 0) >> + return ret; >> + >> + if (ret != VL6180_MODEL_ID_VAL) { >> + dev_err(&client->dev, "invalid model ID %02x\n", ret); >> + return -ENODEV; >> + } >> + >> + ret = vl6180_hold(data, true); >> + if (ret < 0) >> + return ret; >> + >> + ret = vl6180_read_byte(client, VL6180_OUT_OF_RESET); >> + if (ret < 0) >> + return ret; >> + >> + if (ret != 0x01) { >> + dev_err(&client->dev, "device is not fresh out of reset\n"); >> + return -EINVAL; >> + } > Why would it necessarily be fresh out of reset? If it is in some fashion > supposed to be guaranteed here, please add a comment explaining why. >> + >> + ret = vl6180_write_byte(client, VL6180_INTR_CONFIG, >> + VL6180_ALS_READY | VL6180_RANGE_READY); >> + if (ret < 0) >> + return ret; >> + >> + ret = vl6180_write_word(client, VL6180_ALS_IT, VL6180_ALS_IT_100); >> + if (ret < 0) >> + return ret; >> + >> + ret = vl6180_write_byte(client, VL6180_ALS_GAIN, VL6180_ALS_GAIN_1); >> + if (ret < 0) >> + return ret; >> + >> + ret = vl6180_write_byte(client, VL6180_OUT_OF_RESET, 0x00); >> + if (ret < 0) >> + return ret; >> + >> + return vl6180_hold(data, false); >> +} >> + >> +static int vl6180_probe(struct i2c_client *client, >> + const struct i2c_device_id *id) >> +{ >> + struct vl6180_data *data; >> + struct iio_dev *indio_dev; >> + int ret; >> + >> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); >> + if (!indio_dev) >> + return -ENOMEM; >> + >> + data = iio_priv(indio_dev); >> + i2c_set_clientdata(client, indio_dev); >> + data->client = client; >> + mutex_init(&data->lock); >> + >> + indio_dev->dev.parent = &client->dev; >> + indio_dev->info = &vl6180_info; >> + indio_dev->channels = vl6180_channels; >> + indio_dev->num_channels = ARRAY_SIZE(vl6180_channels); >> + indio_dev->name = VL6180_DRV_NAME; >> + indio_dev->modes = INDIO_DIRECT_MODE; >> + >> + ret = vl6180_init(data); >> + if (ret < 0) >> + return ret; >> + >> + ret = devm_iio_device_register(&client->dev, indio_dev); >> + if (ret < 0) >> + return ret; > return devm_iio_device_register directly. > > The static checkers will fire on this anyway, but best to fix > it now. >> + >> + return ret; >> +} >> + >> +static const struct of_device_id vl6180_of_match[] = { >> + { .compatible = "st,vl6180", }, >> + { }, >> +}; >> +MODULE_DEVICE_TABLE(of, vl6180_of_match); >> + >> +static const struct i2c_device_id vl6180_id[] = { >> + { "vl6180", 0 }, >> + { } >> +}; >> +MODULE_DEVICE_TABLE(i2c, vl6180_id); >> + >> +static struct i2c_driver vl6180_driver = { >> + .driver = { >> + .name = VL6180_DRV_NAME, >> + .of_match_table = of_match_ptr(vl6180_of_match), >> + }, >> + .probe = vl6180_probe, >> + .id_table = vl6180_id, >> +}; >> + >> +module_i2c_driver(vl6180_driver); >> + >> +MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx>"); >> +MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@xxxxxxxxx>"); >> +MODULE_DESCRIPTION("STMicro VL6180 ALS and proximity sensor driver"); >> +MODULE_LICENSE("GPL"); >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
