| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * STMicroelectronics uvis25 sensor driver |
| * |
| * Copyright 2017 STMicroelectronics Inc. |
| * |
| * Lorenzo Bianconi <lorenzo.bianconi83@gmail.com> |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/device.h> |
| #include <linux/iio/sysfs.h> |
| #include <linux/delay.h> |
| #include <linux/pm.h> |
| #include <linux/interrupt.h> |
| #include <linux/irqreturn.h> |
| #include <linux/iio/trigger.h> |
| #include <linux/iio/trigger_consumer.h> |
| #include <linux/iio/triggered_buffer.h> |
| #include <linux/iio/buffer.h> |
| #include <linux/regmap.h> |
| |
| #include "st_uvis25.h" |
| |
| #define ST_UVIS25_REG_WHOAMI_ADDR 0x0f |
| #define ST_UVIS25_REG_WHOAMI_VAL 0xca |
| #define ST_UVIS25_REG_CTRL1_ADDR 0x20 |
| #define ST_UVIS25_REG_ODR_MASK BIT(0) |
| #define ST_UVIS25_REG_BDU_MASK BIT(1) |
| #define ST_UVIS25_REG_CTRL2_ADDR 0x21 |
| #define ST_UVIS25_REG_BOOT_MASK BIT(7) |
| #define ST_UVIS25_REG_CTRL3_ADDR 0x22 |
| #define ST_UVIS25_REG_HL_MASK BIT(7) |
| #define ST_UVIS25_REG_STATUS_ADDR 0x27 |
| #define ST_UVIS25_REG_UV_DA_MASK BIT(0) |
| #define ST_UVIS25_REG_OUT_ADDR 0x28 |
| |
| static const struct iio_chan_spec st_uvis25_channels[] = { |
| { |
| .type = IIO_UVINDEX, |
| .address = ST_UVIS25_REG_OUT_ADDR, |
| .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), |
| .scan_index = 0, |
| .scan_type = { |
| .sign = 'u', |
| .realbits = 8, |
| .storagebits = 8, |
| }, |
| }, |
| IIO_CHAN_SOFT_TIMESTAMP(1), |
| }; |
| |
| static int st_uvis25_check_whoami(struct st_uvis25_hw *hw) |
| { |
| int err, data; |
| |
| err = regmap_read(hw->regmap, ST_UVIS25_REG_WHOAMI_ADDR, &data); |
| if (err < 0) { |
| dev_err(regmap_get_device(hw->regmap), |
| "failed to read whoami register\n"); |
| return err; |
| } |
| |
| if (data != ST_UVIS25_REG_WHOAMI_VAL) { |
| dev_err(regmap_get_device(hw->regmap), |
| "wrong whoami {%02x vs %02x}\n", |
| data, ST_UVIS25_REG_WHOAMI_VAL); |
| return -ENODEV; |
| } |
| |
| return 0; |
| } |
| |
| static int st_uvis25_set_enable(struct st_uvis25_hw *hw, bool enable) |
| { |
| int err; |
| |
| err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR, |
| ST_UVIS25_REG_ODR_MASK, enable); |
| if (err < 0) |
| return err; |
| |
| hw->enabled = enable; |
| |
| return 0; |
| } |
| |
| static int st_uvis25_read_oneshot(struct st_uvis25_hw *hw, u8 addr, int *val) |
| { |
| int err; |
| |
| err = st_uvis25_set_enable(hw, true); |
| if (err < 0) |
| return err; |
| |
| msleep(1500); |
| |
| /* |
| * in order to avoid possible race conditions with interrupt |
| * generation, disable the sensor first and then poll output |
| * register. That sequence guarantees the interrupt will be reset |
| * when irq line is unmasked |
| */ |
| err = st_uvis25_set_enable(hw, false); |
| if (err < 0) |
| return err; |
| |
| err = regmap_read(hw->regmap, addr, val); |
| |
| return err < 0 ? err : IIO_VAL_INT; |
| } |
| |
| static int st_uvis25_read_raw(struct iio_dev *iio_dev, |
| struct iio_chan_spec const *ch, |
| int *val, int *val2, long mask) |
| { |
| int ret; |
| |
| ret = iio_device_claim_direct_mode(iio_dev); |
| if (ret) |
| return ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_PROCESSED: { |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| |
| /* |
| * mask irq line during oneshot read since the sensor |
| * does not export the capability to disable data-ready line |
| * in the register map and it is enabled by default. |
| * If the line is unmasked during read_raw() it will be set |
| * active and never reset since the trigger is disabled |
| */ |
| if (hw->irq > 0) |
| disable_irq(hw->irq); |
| ret = st_uvis25_read_oneshot(hw, ch->address, val); |
| if (hw->irq > 0) |
| enable_irq(hw->irq); |
| break; |
| } |
| default: |
| ret = -EINVAL; |
| break; |
| } |
| |
| iio_device_release_direct_mode(iio_dev); |
| |
| return ret; |
| } |
| |
| static irqreturn_t st_uvis25_trigger_handler_thread(int irq, void *private) |
| { |
| struct st_uvis25_hw *hw = private; |
| int err, status; |
| |
| err = regmap_read(hw->regmap, ST_UVIS25_REG_STATUS_ADDR, &status); |
| if (err < 0) |
| return IRQ_HANDLED; |
| |
| if (!(status & ST_UVIS25_REG_UV_DA_MASK)) |
| return IRQ_NONE; |
| |
| iio_trigger_poll_chained(hw->trig); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int st_uvis25_allocate_trigger(struct iio_dev *iio_dev) |
| { |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| struct device *dev = regmap_get_device(hw->regmap); |
| bool irq_active_low = false; |
| unsigned long irq_type; |
| int err; |
| |
| irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq)); |
| |
| switch (irq_type) { |
| case IRQF_TRIGGER_HIGH: |
| case IRQF_TRIGGER_RISING: |
| break; |
| case IRQF_TRIGGER_LOW: |
| case IRQF_TRIGGER_FALLING: |
| irq_active_low = true; |
| break; |
| default: |
| dev_info(dev, "mode %lx unsupported\n", irq_type); |
| return -EINVAL; |
| } |
| |
| err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL3_ADDR, |
| ST_UVIS25_REG_HL_MASK, irq_active_low); |
| if (err < 0) |
| return err; |
| |
| err = devm_request_threaded_irq(dev, hw->irq, NULL, |
| st_uvis25_trigger_handler_thread, |
| irq_type | IRQF_ONESHOT, |
| iio_dev->name, hw); |
| if (err) { |
| dev_err(dev, "failed to request trigger irq %d\n", |
| hw->irq); |
| return err; |
| } |
| |
| hw->trig = devm_iio_trigger_alloc(dev, "%s-trigger", |
| iio_dev->name); |
| if (!hw->trig) |
| return -ENOMEM; |
| |
| iio_trigger_set_drvdata(hw->trig, iio_dev); |
| hw->trig->dev.parent = dev; |
| |
| return devm_iio_trigger_register(dev, hw->trig); |
| } |
| |
| static int st_uvis25_buffer_preenable(struct iio_dev *iio_dev) |
| { |
| return st_uvis25_set_enable(iio_priv(iio_dev), true); |
| } |
| |
| static int st_uvis25_buffer_postdisable(struct iio_dev *iio_dev) |
| { |
| return st_uvis25_set_enable(iio_priv(iio_dev), false); |
| } |
| |
| static const struct iio_buffer_setup_ops st_uvis25_buffer_ops = { |
| .preenable = st_uvis25_buffer_preenable, |
| .postenable = iio_triggered_buffer_postenable, |
| .predisable = iio_triggered_buffer_predisable, |
| .postdisable = st_uvis25_buffer_postdisable, |
| }; |
| |
| static irqreturn_t st_uvis25_buffer_handler_thread(int irq, void *p) |
| { |
| struct iio_poll_func *pf = p; |
| struct iio_dev *iio_dev = pf->indio_dev; |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| unsigned int val; |
| int err; |
| |
| err = regmap_read(hw->regmap, ST_UVIS25_REG_OUT_ADDR, &val); |
| if (err < 0) |
| goto out; |
| |
| hw->scan.chan = val; |
| |
| iio_push_to_buffers_with_timestamp(iio_dev, &hw->scan, |
| iio_get_time_ns(iio_dev)); |
| |
| out: |
| iio_trigger_notify_done(hw->trig); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int st_uvis25_allocate_buffer(struct iio_dev *iio_dev) |
| { |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| |
| return devm_iio_triggered_buffer_setup(regmap_get_device(hw->regmap), |
| iio_dev, NULL, |
| st_uvis25_buffer_handler_thread, |
| &st_uvis25_buffer_ops); |
| } |
| |
| static const struct iio_info st_uvis25_info = { |
| .read_raw = st_uvis25_read_raw, |
| }; |
| |
| static int st_uvis25_init_sensor(struct st_uvis25_hw *hw) |
| { |
| int err; |
| |
| err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL2_ADDR, |
| ST_UVIS25_REG_BOOT_MASK, 1); |
| if (err < 0) |
| return err; |
| |
| msleep(2000); |
| |
| return regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR, |
| ST_UVIS25_REG_BDU_MASK, 1); |
| } |
| |
| int st_uvis25_probe(struct device *dev, int irq, struct regmap *regmap) |
| { |
| struct st_uvis25_hw *hw; |
| struct iio_dev *iio_dev; |
| int err; |
| |
| iio_dev = devm_iio_device_alloc(dev, sizeof(*hw)); |
| if (!iio_dev) |
| return -ENOMEM; |
| |
| dev_set_drvdata(dev, (void *)iio_dev); |
| |
| hw = iio_priv(iio_dev); |
| hw->irq = irq; |
| hw->regmap = regmap; |
| |
| err = st_uvis25_check_whoami(hw); |
| if (err < 0) |
| return err; |
| |
| iio_dev->modes = INDIO_DIRECT_MODE; |
| iio_dev->dev.parent = dev; |
| iio_dev->channels = st_uvis25_channels; |
| iio_dev->num_channels = ARRAY_SIZE(st_uvis25_channels); |
| iio_dev->name = ST_UVIS25_DEV_NAME; |
| iio_dev->info = &st_uvis25_info; |
| |
| err = st_uvis25_init_sensor(hw); |
| if (err < 0) |
| return err; |
| |
| if (hw->irq > 0) { |
| err = st_uvis25_allocate_buffer(iio_dev); |
| if (err < 0) |
| return err; |
| |
| err = st_uvis25_allocate_trigger(iio_dev); |
| if (err) |
| return err; |
| } |
| |
| return devm_iio_device_register(dev, iio_dev); |
| } |
| EXPORT_SYMBOL(st_uvis25_probe); |
| |
| static int __maybe_unused st_uvis25_suspend(struct device *dev) |
| { |
| struct iio_dev *iio_dev = dev_get_drvdata(dev); |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| |
| return regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR, |
| ST_UVIS25_REG_ODR_MASK, 0); |
| } |
| |
| static int __maybe_unused st_uvis25_resume(struct device *dev) |
| { |
| struct iio_dev *iio_dev = dev_get_drvdata(dev); |
| struct st_uvis25_hw *hw = iio_priv(iio_dev); |
| |
| if (hw->enabled) |
| return regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR, |
| ST_UVIS25_REG_ODR_MASK, 1); |
| |
| return 0; |
| } |
| |
| const struct dev_pm_ops st_uvis25_pm_ops = { |
| SET_SYSTEM_SLEEP_PM_OPS(st_uvis25_suspend, st_uvis25_resume) |
| }; |
| EXPORT_SYMBOL(st_uvis25_pm_ops); |
| |
| MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>"); |
| MODULE_DESCRIPTION("STMicroelectronics uvis25 sensor driver"); |
| MODULE_LICENSE("GPL v2"); |