On Tue, 10 Apr 2018 10:44:52 +0200 Sean Nyekjaer <sean.nyekjaer@xxxxxxxxx> wrote: > This patch adds support for the Texas Intruments DAC5755 Family. > > Signed-off-by: Sean Nyekjaer <sean.nyekjaer@xxxxxxxxx> First comment, please don't be tempted to reply to an earlier version of a patch with a new version. It just makes for confusing reading (particularly once we reach version 15 *evil laugh*) I nearly missed this entirely as it was many pages earlier in my email. A few oddities inline in handling of pwrdwn in particular. Thanks, Jonathan > --- > > Still not have hardware :-( Ready next week I hope. So still RFC. > > v2: > Addressed comments from Jonathan and Peter > - improved readability > - i2c return check fixed > - added structure pointer instead of copying elements > - splitted single and quad operations with function pointers > > drivers/iio/dac/Kconfig | 10 + > drivers/iio/dac/Makefile | 1 + > drivers/iio/dac/ti-dac5571.c | 430 +++++++++++++++++++++++++++++++++++ > 3 files changed, 441 insertions(+) > create mode 100644 drivers/iio/dac/ti-dac5571.c > > diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig > index 965d5c0d2468..b64fabbc74f8 100644 > --- a/drivers/iio/dac/Kconfig > +++ b/drivers/iio/dac/Kconfig > @@ -320,6 +320,16 @@ config TI_DAC082S085 > > If compiled as a module, it will be called ti-dac082s085. > > +config TI_DAC5571 > + tristate "Texas Instruments 8/10/12/16-bit 1/2/4-channel DAC driver" > + depends on I2C > + help > + Driver for the Texas Instruments > + DAC5571, DAC6571, DAC7571, DAC5574, DAC6574, DAC7574, DAC5573, > + DAC6573, DAC7573, DAC8571, DAC8574. > + > + If compiled as a module, it will be called ti-dac5571. > + > config VF610_DAC > tristate "Vybrid vf610 DAC driver" > depends on OF > diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile > index 81e710ed7491..1ab358d522ee 100644 > --- a/drivers/iio/dac/Makefile > +++ b/drivers/iio/dac/Makefile > @@ -35,4 +35,5 @@ obj-$(CONFIG_MCP4922) += mcp4922.o > obj-$(CONFIG_STM32_DAC_CORE) += stm32-dac-core.o > obj-$(CONFIG_STM32_DAC) += stm32-dac.o > obj-$(CONFIG_TI_DAC082S085) += ti-dac082s085.o > +obj-$(CONFIG_TI_DAC5571) += ti-dac5571.o > obj-$(CONFIG_VF610_DAC) += vf610_dac.o > diff --git a/drivers/iio/dac/ti-dac5571.c b/drivers/iio/dac/ti-dac5571.c > new file mode 100644 > index 000000000000..0ee5ca1ce6eb > --- /dev/null > +++ b/drivers/iio/dac/ti-dac5571.c > @@ -0,0 +1,430 @@ > +/* > + * ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver > + * > + * Copyright (C) 2018 Prevas A/S > + * > + * http://www.ti.com/lit/ds/symlink/dac5571.pdf > + * http://www.ti.com/lit/ds/symlink/dac6571.pdf > + * http://www.ti.com/lit/ds/symlink/dac7571.pdf > + * http://www.ti.com/lit/ds/symlink/dac5574.pdf > + * http://www.ti.com/lit/ds/symlink/dac6574.pdf > + * http://www.ti.com/lit/ds/symlink/dac7574.pdf > + * http://www.ti.com/lit/ds/symlink/dac5573.pdf > + * http://www.ti.com/lit/ds/symlink/dac6573.pdf > + * http://www.ti.com/lit/ds/symlink/dac7573.pdf > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License (version 2) as > + * published by the Free Software Foundation. > + */ > + > +#include <linux/iio/iio.h> > +#include <linux/i2c.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/of.h> > +#include <linux/regulator/consumer.h> > + > +enum chip_id { > + single_8bit, single_10bit, single_12bit, > + quad_8bit, quad_10bit, quad_12bit > +}; > + > +#define DAC5571_SINGLE_CHANNEL 1 > +#define DAC5571_QUAD_CHANNEL 4 > + > +struct dac5571_spec { > + u8 num_channels; > + u8 resolution; > +}; > + > +static const struct dac5571_spec dac5571_spec[] = { > + [single_8bit] = {.num_channels = 1, .resolution = 8}, > + [single_10bit] = {.num_channels = 1, .resolution = 10}, > + [single_12bit] = {.num_channels = 1, .resolution = 12}, > + [quad_8bit] = {.num_channels = 4, .resolution = 8}, > + [quad_10bit] = {.num_channels = 4, .resolution = 10}, > + [quad_12bit] = {.num_channels = 4, .resolution = 12}, > +}; > + > +struct dac5571_data { > + struct i2c_client *client; > + int id; > + struct mutex lock; > + struct regulator *vref; > + u16 val[4]; > + bool powerdown; > + u8 powerdown_mode; > + struct dac5571_spec const *spec; > + int (*dac5571_cmd) (struct dac5571_data *, int, u16); > + int (*dac5571_pwrdwn) (struct dac5571_data *, int, u8); > + u8 buf[3] ____cacheline_aligned; > +}; > + > +#define DAC5571_POWERDOWN(mode) ((mode) + 1) > +#define DAC5571_POWERDOWN_FLAG BIT(0) > +#define DAC5571_CHANNEL_SELECT BIT(1) > +#define DAC5571_LOADMODE_DIRECT BIT(4) > +#define DAC5571_SINGLE_PWRDWN_BITS 4 > +#define DAC5571_QUAD_PWRDWN_BITS 6 > + > +static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val) > +{ > + unsigned int shift; > + > + shift = 12 - data->spec->resolution; > + data->buf[0] = val << shift; > + data->buf[1] = val >> (8 - shift); > + return i2c_master_send(data->client, data->buf, 2); > +} > + > + > +static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val) > +{ > + unsigned int shift; > + > + shift = 16 - data->spec->resolution; > + data->buf[0] = val << shift; > + data->buf[1] = (val >> (8 - shift)); > + data->buf[2] = (channel << DAC5571_CHANNEL_SELECT) | > + DAC5571_LOADMODE_DIRECT; > + return i2c_master_send(data->client, data->buf, 3); > +} > + > +static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn) > +{ > + unsigned int shift; > + > + shift = 12 - data->spec->resolution; > + data->buf[0] = 0; > + data->buf[1] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS; > + return i2c_master_send(data->client, data->buf, 2); > +} > + > +static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn) > +{ > + unsigned int shift; > + > + shift = 16 - data->spec->resolution; > + data->buf[0] = 0; > + data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS; > + data->buf[2] = (channel << DAC5571_CHANNEL_SELECT) | > + DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG; > + return i2c_master_send(data->client, data->buf, 3); I would check the return == 3 and return an error if not. > +} > + > +static const char *const dac5571_powerdown_modes[] = { > + "1kohm_to_gnd", "100kohm_to_gnd", "three_state", > +}; > + > +static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev, > + const struct iio_chan_spec *chan) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + > + return data->powerdown_mode; > +} > + > +static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev, > + const struct iio_chan_spec *chan, > + unsigned int mode) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + int ret = 0; > + > + if (data->powerdown_mode == mode) > + return 0; > + > + mutex_lock(&data->lock); > + if (data->powerdown) { > + ret = data->dac5571_pwrdwn(data, chan->channel, > + DAC5571_POWERDOWN(mode)); > + if (ret <= 0) > + goto out; This is unusual. I would handle the 0 case inside the pwrdwn functions so we can assume 0 is good. > + } > + data->powerdown_mode = mode; > + > + out: > + mutex_unlock(&data->lock); blank line here would help readability a little. > + return ret; > +} > + > +static const struct iio_enum dac5571_powerdown_mode = { > + .items = dac5571_powerdown_modes, > + .num_items = ARRAY_SIZE(dac5571_powerdown_modes), > + .get = dac5571_get_powerdown_mode, > + .set = dac5571_set_powerdown_mode, > +}; > + > +static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev, > + uintptr_t private, > + const struct iio_chan_spec *chan, > + char *buf) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + > + return sprintf(buf, "%d\n", data->powerdown); > +} > + > +static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev, > + uintptr_t private, > + const struct iio_chan_spec *chan, > + const char *buf, size_t len) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + bool powerdown; > + int ret; > + > + ret = strtobool(buf, &powerdown); > + if (ret) > + return ret; > + > + if (data->powerdown == powerdown) > + return len; > + > + mutex_lock(&data->lock); > + if (powerdown) > + ret = data->dac5571_pwrdwn(data, chan->channel, > + DAC5571_POWERDOWN(data->powerdown_mode)); > + else > + ret = data->dac5571_cmd(data, chan->channel, data->val[0]); > + if (ret <= 0) > + data->powerdown = powerdown; Not sure I follow the logic here. I think we failed to power down but you are storing it anyway? I would indent the bad path and use a goto to jump statements in the good path. > + mutex_unlock(&data->lock); > + > + return ret ? ret : len; > +} > + > + > +static const struct iio_chan_spec_ext_info dac5571_ext_info[] = { > + { > + .name = "powerdown", > + .read = dac5571_read_powerdown, > + .write = dac5571_write_powerdown, > + .shared = IIO_SHARED_BY_TYPE, > + }, > + IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode), > + IIO_ENUM_AVAILABLE("powerdown_mode", &dac5571_powerdown_mode), > + {}, > +}; > + > +#define dac5571_CHANNEL(chan, name) { \ > + .type = IIO_VOLTAGE, \ > + .channel = (chan), \ > + .address = (chan), \ > + .indexed = true, \ > + .output = true, \ > + .datasheet_name = name, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > + .ext_info = dac5571_ext_info, \ > +} > + > +static const struct iio_chan_spec dac5571_channels[] = { > + dac5571_CHANNEL(0, "A"), > + dac5571_CHANNEL(1, "B"), > + dac5571_CHANNEL(2, "C"), > + dac5571_CHANNEL(3, "D"), > +}; > + > +static int dac5571_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + *val = data->val[chan->channel]; > + return IIO_VAL_INT; break after a return is pointless, get rid of them. > + break; > + > + case IIO_CHAN_INFO_SCALE: > + ret = regulator_get_voltage(data->vref); > + if (ret < 0) > + return ret; > + > + *val = ret / 1000; > + *val2 = data->spec->resolution; > + return IIO_VAL_FRACTIONAL_LOG2; > + break; > + > + default: > + ret = -EINVAL; return -EINVAL; > + } > + > + return ret; Not needed if we return from the default: case. > +} > + > +static int dac5571_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct dac5571_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + if (data->val[chan->channel] == val) > + return 0; > + > + if (val >= (1 << data->spec->resolution) || val < 0) > + return -EINVAL; > + > + if (data->powerdown) > + return -EBUSY; > + > + mutex_lock(&data->lock); > + ret = data->dac5571_cmd(data, chan->channel, val); > + if (ret <= 0) > + data->val[chan->channel] = val; > + mutex_unlock(&data->lock); > + return ret; > + break; > + > + default: > + return -EINVAL; > + } > + > + return ret; > +} > + > +static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + long mask) > +{ > + return IIO_VAL_INT; > +} > + > +static const struct iio_info dac5571_info = { > + .read_raw = dac5571_read_raw, > + .write_raw = dac5571_write_raw, > + .write_raw_get_fmt = dac5571_write_raw_get_fmt, > +}; > + > +static int dac5571_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + const struct dac5571_spec *spec; > + struct dac5571_data *data; > + struct iio_dev *indio_dev; > + int ret, i; > + > + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); > + if (!indio_dev) > + return -ENOMEM; > + > + data = iio_priv(indio_dev); > + i2c_set_clientdata(client, indio_dev); > + data->client = client; > + > + indio_dev->dev.parent = dev; > + indio_dev->dev.of_node = client->dev.of_node; > + indio_dev->info = &dac5571_info; > + indio_dev->name = id->name; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = dac5571_channels; > + > + spec = &dac5571_spec[id->driver_data]; > + indio_dev->num_channels = spec->num_channels; > + data->spec = spec; > + > + data->vref = devm_regulator_get(dev, "vref"); > + if (IS_ERR(data->vref)) > + return PTR_ERR(data->vref); > + > + ret = regulator_enable(data->vref); > + if (ret < 0) > + return ret; > + > + mutex_init(&data->lock); > + > + switch (spec->num_channels) { > + case DAC5571_SINGLE_CHANNEL: > + data->dac5571_cmd = dac5571_cmd_single; > + data->dac5571_pwrdwn = dac5571_pwrdwn_single; > + break; > + case DAC5571_QUAD_CHANNEL: > + data->dac5571_cmd = dac5571_cmd_quad; > + data->dac5571_pwrdwn = dac5571_pwrdwn_quad; > + break; > + default: > + goto err; > + break; > + } > + > + for (i = 0; i < spec->num_channels; i++) { > + ret = data->dac5571_cmd(data, i, 0); > + if (ret <= 0) { > + dev_err(dev, "failed to initialize channel %d to 0\n", i); > + goto err; > + } > + } > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err; > + > + return 0; > + > + err: > + regulator_disable(data->vref); > + return ret; > +} > + > +static int dac5571_remove(struct i2c_client *i2c) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(i2c); > + struct dac5571_data *data = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + regulator_disable(data->vref); > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id dac5571_of_id[] = { > + {.compatible = "ti,dac5571"}, > + {.compatible = "ti,dac6571"}, > + {.compatible = "ti,dac7571"}, > + {.compatible = "ti,dac5574"}, > + {.compatible = "ti,dac6574"}, > + {.compatible = "ti,dac7574"}, > + {.compatible = "ti,dac5573"}, > + {.compatible = "ti,dac6573"}, > + {.compatible = "ti,dac7573"}, > + {} > +}; > +MODULE_DEVICE_TABLE(of, dac5571_of_id); > +#endif > + > +static const struct i2c_device_id dac5571_id[] = { > + {"dac5571", single_8bit}, > + {"dac6571", single_10bit}, > + {"dac7571", single_12bit}, > + {"dac5574", quad_8bit}, > + {"dac6574", quad_10bit}, > + {"dac7574", quad_12bit}, > + {"dac5573", quad_8bit}, > + {"dac6573", quad_10bit}, > + {"dac7573", quad_12bit}, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, dac5571_id); > + > +static struct i2c_driver dac5571_driver = { > + .driver = { > + .name = "ti-dac5571", > + }, > + .probe = dac5571_probe, > + .remove = dac5571_remove, > + .id_table = dac5571_id, > +}; > +module_i2c_driver(dac5571_driver); > + > +MODULE_AUTHOR("Sean Nyekjaer <sean.nyekjaer@xxxxxxxxx>"); > +MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver"); > +MODULE_LICENSE("GPL v2"); -- 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
