diff options
Diffstat (limited to 'drivers/iio/adc/mcp3911.c')
| -rw-r--r-- | drivers/iio/adc/mcp3911.c | 62 |
1 files changed, 55 insertions, 7 deletions
diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c index 6748b44d568d..a6f21791c685 100644 --- a/drivers/iio/adc/mcp3911.c +++ b/drivers/iio/adc/mcp3911.c @@ -6,11 +6,13 @@ * Copyright (C) 2018 Kent Gustavsson <kent@minoris.se> */ #include <linux/bitfield.h> -#include <linux/bits.h> +#include <linux/bitops.h> #include <linux/cleanup.h> #include <linux/clk.h> #include <linux/delay.h> +#include <linux/dev_printk.h> #include <linux/err.h> +#include <linux/gpio/consumer.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/property.h> @@ -79,6 +81,8 @@ #define MCP3910_CONFIG1_CLKEXT BIT(6) #define MCP3910_CONFIG1_VREFEXT BIT(7) +#define MCP3910_CHANNEL(ch) (MCP3911_REG_CHANNEL0 + (ch)) + #define MCP3910_REG_OFFCAL_CH0 0x0f #define MCP3910_OFFCAL(ch) (MCP3910_REG_OFFCAL_CH0 + (ch) * 6) @@ -110,6 +114,7 @@ struct mcp3911_chip_info { int (*get_offset)(struct mcp3911 *adc, int channel, int *val); int (*set_offset)(struct mcp3911 *adc, int channel, int val); int (*set_scale)(struct mcp3911 *adc, int channel, u32 val); + int (*get_raw)(struct mcp3911 *adc, int channel, int *val); }; struct mcp3911 { @@ -170,6 +175,18 @@ static int mcp3911_update(struct mcp3911 *adc, u8 reg, u32 mask, u32 val, u8 len return mcp3911_write(adc, reg, val, len); } +static int mcp3911_read_s24(struct mcp3911 *const adc, u8 const reg, s32 *const val) +{ + u32 uval; + int const ret = mcp3911_read(adc, reg, &uval, 3); + + if (ret) + return ret; + + *val = sign_extend32(uval, 23); + return ret; +} + static int mcp3910_enable_offset(struct mcp3911 *adc, bool enable) { unsigned int mask = MCP3910_CONFIG0_EN_OFFCAL; @@ -194,6 +211,11 @@ static int mcp3910_set_offset(struct mcp3911 *adc, int channel, int val) return adc->chip->enable_offset(adc, 1); } +static int mcp3910_get_raw(struct mcp3911 *adc, int channel, s32 *val) +{ + return mcp3911_read_s24(adc, MCP3910_CHANNEL(channel), val); +} + static int mcp3911_enable_offset(struct mcp3911 *adc, bool enable) { unsigned int mask = MCP3911_STATUSCOM_EN_OFFCAL; @@ -218,6 +240,11 @@ static int mcp3911_set_offset(struct mcp3911 *adc, int channel, int val) return adc->chip->enable_offset(adc, 1); } +static int mcp3911_get_raw(struct mcp3911 *adc, int channel, s32 *val) +{ + return mcp3911_read_s24(adc, MCP3911_CHANNEL(channel), val); +} + static int mcp3910_get_osr(struct mcp3911 *adc, u32 *val) { int ret; @@ -321,12 +348,9 @@ static int mcp3911_read_raw(struct iio_dev *indio_dev, guard(mutex)(&adc->lock); switch (mask) { case IIO_CHAN_INFO_RAW: - ret = mcp3911_read(adc, - MCP3911_CHANNEL(channel->channel), val, 3); + ret = adc->chip->get_raw(adc, channel->channel, val); if (ret) return ret; - - *val = sign_extend32(*val, 23); return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: ret = adc->chip->get_offset(adc, channel->channel, val); @@ -516,8 +540,8 @@ static irqreturn_t mcp3911_trigger_handler(int irq, void *p) adc->scan.channels[i] = get_unaligned_be24(&adc->rx_buf[scan_chan->channel * 3]); i++; } - iio_push_to_buffers_with_timestamp(indio_dev, &adc->scan, - iio_get_time_ns(indio_dev)); + iio_push_to_buffers_with_ts(indio_dev, &adc->scan, sizeof(adc->scan), + iio_get_time_ns(indio_dev)); out: iio_trigger_notify_done(indio_dev->trig); @@ -684,6 +708,7 @@ static const struct iio_trigger_ops mcp3911_trigger_ops = { static int mcp3911_probe(struct spi_device *spi) { struct device *dev = &spi->dev; + struct gpio_desc *gpio_reset; struct iio_dev *indio_dev; struct mcp3911 *adc; bool external_vref; @@ -728,6 +753,22 @@ static int mcp3911_probe(struct spi_device *spi) } dev_dbg(dev, "use device address %i\n", adc->dev_addr); + gpio_reset = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(gpio_reset)) + return dev_err_probe(dev, PTR_ERR(gpio_reset), + "Cannot get reset GPIO\n"); + + if (gpio_reset) { + gpiod_set_value_cansleep(gpio_reset, 0); + + /* + * Settling time after Hard Reset Mode (determined experimentally): + * 330 micro-seconds are too few; 470 micro-seconds are sufficient. + * Just in case, we add some safety factor... + */ + fsleep(600); + } + ret = adc->chip->config(adc, external_vref); if (ret) return ret; @@ -799,6 +840,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, [MCP3911] = { .channels = mcp3911_channels, @@ -810,6 +852,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3911_get_offset, .set_offset = mcp3911_set_offset, .set_scale = mcp3911_set_scale, + .get_raw = mcp3911_get_raw, }, [MCP3912] = { .channels = mcp3912_channels, @@ -821,6 +864,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, [MCP3913] = { .channels = mcp3913_channels, @@ -832,6 +876,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, [MCP3914] = { .channels = mcp3914_channels, @@ -843,6 +888,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, [MCP3918] = { .channels = mcp3918_channels, @@ -854,6 +900,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, [MCP3919] = { .channels = mcp3919_channels, @@ -865,6 +912,7 @@ static const struct mcp3911_chip_info mcp3911_chip_info[] = { .get_offset = mcp3910_get_offset, .set_offset = mcp3910_set_offset, .set_scale = mcp3910_set_scale, + .get_raw = mcp3910_get_raw, }, }; static const struct of_device_id mcp3911_dt_ids[] = { |