diff options
author | Simon Xue <xxm@rock-chips.com> | 2020-06-24 01:30:11 +0200 |
---|---|---|
committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-06-27 13:09:15 +0100 |
commit | 4e130dc7b41348b13684f0758c26cc6cf72a3449 (patch) | |
tree | 782a0447c014a77ce7fc3eef1f7a83cdb821d9e9 | |
parent | 71eb7c855bd0cd168541305e3d6dab16bf0b0dfe (diff) | |
download | linux-4e130dc7b41348b13684f0758c26cc6cf72a3449.tar.bz2 |
iio: adc: rockchip_saradc: Add support iio buffers
Add the ability to also support access via (triggered) buffers
next to the existing direct mode.
Device in question is the Odroid Go Advance that connects a joystick
to two of the saradc channels for X and Y axis and the new (and still
pending) adc joystick driver of course wants to use triggered buffers
from the iio subsystem.
Signed-off-by: Simon Xue <xxm@rock-chips.com>
[some simplifications and added commit description]
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
-rw-r--r-- | drivers/iio/adc/rockchip_saradc.c | 145 |
1 files changed, 110 insertions, 35 deletions
diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c index 03ca471f5cb7..70af111e4046 100644 --- a/drivers/iio/adc/rockchip_saradc.c +++ b/drivers/iio/adc/rockchip_saradc.c @@ -15,7 +15,10 @@ #include <linux/delay.h> #include <linux/reset.h> #include <linux/regulator/consumer.h> +#include <linux/iio/buffer.h> #include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> #define SARADC_DATA 0x00 @@ -32,9 +35,9 @@ #define SARADC_DLY_PU_SOC_MASK 0x3f #define SARADC_TIMEOUT msecs_to_jiffies(100) +#define SARADC_MAX_CHANNELS 6 struct rockchip_saradc_data { - int num_bits; const struct iio_chan_spec *channels; int num_channels; unsigned long clk_rate; @@ -49,8 +52,37 @@ struct rockchip_saradc { struct reset_control *reset; const struct rockchip_saradc_data *data; u16 last_val; + const struct iio_chan_spec *last_chan; }; +static void rockchip_saradc_power_down(struct rockchip_saradc *info) +{ + /* Clear irq & power down adc */ + writel_relaxed(0, info->regs + SARADC_CTRL); +} + +static int rockchip_saradc_conversion(struct rockchip_saradc *info, + struct iio_chan_spec const *chan) +{ + reinit_completion(&info->completion); + + /* 8 clock periods as delay between power up and start cmd */ + writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC); + + info->last_chan = chan; + + /* Select the channel to be used and trigger conversion */ + writel(SARADC_CTRL_POWER_CTRL + | (chan->channel & SARADC_CTRL_CHN_MASK) + | SARADC_CTRL_IRQ_ENABLE, + info->regs + SARADC_CTRL); + + if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT)) + return -ETIMEDOUT; + + return 0; +} + static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) @@ -62,22 +94,11 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, case IIO_CHAN_INFO_RAW: mutex_lock(&indio_dev->mlock); - reinit_completion(&info->completion); - - /* 8 clock periods as delay between power up and start cmd */ - writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC); - - /* Select the channel to be used and trigger conversion */ - writel(SARADC_CTRL_POWER_CTRL - | (chan->channel & SARADC_CTRL_CHN_MASK) - | SARADC_CTRL_IRQ_ENABLE, - info->regs + SARADC_CTRL); - - if (!wait_for_completion_timeout(&info->completion, - SARADC_TIMEOUT)) { - writel_relaxed(0, info->regs + SARADC_CTRL); + ret = rockchip_saradc_conversion(info, chan); + if (ret) { + rockchip_saradc_power_down(info); mutex_unlock(&indio_dev->mlock); - return -ETIMEDOUT; + return ret; } *val = info->last_val; @@ -91,7 +112,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, } *val = ret / 1000; - *val2 = info->data->num_bits; + *val2 = chan->scan_type.realbits; return IIO_VAL_FRACTIONAL_LOG2; default: return -EINVAL; @@ -104,10 +125,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id) /* Read value */ info->last_val = readl_relaxed(info->regs + SARADC_DATA); - info->last_val &= GENMASK(info->data->num_bits - 1, 0); + info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0); - /* Clear irq & power down adc */ - writel_relaxed(0, info->regs + SARADC_CTRL); + rockchip_saradc_power_down(info); complete(&info->completion); @@ -118,51 +138,55 @@ static const struct iio_info rockchip_saradc_iio_info = { .read_raw = rockchip_saradc_read_raw, }; -#define SARADC_CHANNEL(_index, _id) { \ +#define SARADC_CHANNEL(_index, _id, _res) { \ .type = IIO_VOLTAGE, \ .indexed = 1, \ .channel = _index, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .datasheet_name = _id, \ + .scan_index = _index, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = _res, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ } static const struct iio_chan_spec rockchip_saradc_iio_channels[] = { - SARADC_CHANNEL(0, "adc0"), - SARADC_CHANNEL(1, "adc1"), - SARADC_CHANNEL(2, "adc2"), + SARADC_CHANNEL(0, "adc0", 10), + SARADC_CHANNEL(1, "adc1", 10), + SARADC_CHANNEL(2, "adc2", 10), }; static const struct rockchip_saradc_data saradc_data = { - .num_bits = 10, .channels = rockchip_saradc_iio_channels, .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels), .clk_rate = 1000000, }; static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = { - SARADC_CHANNEL(0, "adc0"), - SARADC_CHANNEL(1, "adc1"), + SARADC_CHANNEL(0, "adc0", 12), + SARADC_CHANNEL(1, "adc1", 12), }; static const struct rockchip_saradc_data rk3066_tsadc_data = { - .num_bits = 12, .channels = rockchip_rk3066_tsadc_iio_channels, .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels), .clk_rate = 50000, }; static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = { - SARADC_CHANNEL(0, "adc0"), - SARADC_CHANNEL(1, "adc1"), - SARADC_CHANNEL(2, "adc2"), - SARADC_CHANNEL(3, "adc3"), - SARADC_CHANNEL(4, "adc4"), - SARADC_CHANNEL(5, "adc5"), + SARADC_CHANNEL(0, "adc0", 10), + SARADC_CHANNEL(1, "adc1", 10), + SARADC_CHANNEL(2, "adc2", 10), + SARADC_CHANNEL(3, "adc3", 10), + SARADC_CHANNEL(4, "adc4", 10), + SARADC_CHANNEL(5, "adc5", 10), }; static const struct rockchip_saradc_data rk3399_saradc_data = { - .num_bits = 10, .channels = rockchip_rk3399_saradc_iio_channels, .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels), .clk_rate = 1000000, @@ -214,6 +238,46 @@ static void rockchip_saradc_regulator_disable(void *data) regulator_disable(info->vref); } +static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *i_dev = pf->indio_dev; + struct rockchip_saradc *info = iio_priv(i_dev); + /* + * @values: each channel takes an u16 value + * @timestamp: will be 8-byte aligned automatically + */ + struct { + u16 values[SARADC_MAX_CHANNELS]; + int64_t timestamp; + } data; + int ret; + int i, j = 0; + + mutex_lock(&i_dev->mlock); + + for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) { + const struct iio_chan_spec *chan = &i_dev->channels[i]; + + ret = rockchip_saradc_conversion(info, chan); + if (ret) { + rockchip_saradc_power_down(info); + goto out; + } + + data.values[j] = info->last_val; + j++; + } + + iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev)); +out: + mutex_unlock(&i_dev->mlock); + + iio_trigger_notify_done(i_dev->trig); + + return IRQ_HANDLED; +} + static int rockchip_saradc_probe(struct platform_device *pdev) { struct rockchip_saradc *info = NULL; @@ -242,6 +306,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev) info->data = match->data; + /* Sanity check for possible later IP variants with more channels */ + if (info->data->num_channels > SARADC_MAX_CHANNELS) { + dev_err(&pdev->dev, "max channels exceeded"); + return -EINVAL; + } + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); info->regs = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(info->regs)) @@ -354,6 +424,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev) indio_dev->channels = info->data->channels; indio_dev->num_channels = info->data->num_channels; + ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL, + rockchip_saradc_trigger_handler, + NULL); + if (ret) + return ret; return devm_iio_device_register(&pdev->dev, indio_dev); } |