On Thu, 7 Dec 2023 15:42:56 -0300
Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> wrote:
> Add support for Analog Devices AD7091R-2, AD7091R-4, and AD7091R-8
> low power 12-Bit SAR ADCs with SPI interface.
> Extend ad7091r-base driver so it can be used by the AD7091R-8 driver.
>
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
A few trivial things inline.
Otherwise looks pretty good to me.
Jonathan
> diff --git a/drivers/iio/adc/ad7091r8.c b/drivers/iio/adc/ad7091r8.c
> new file mode 100644
> index 000000000000..8dc0f784913b
> --- /dev/null
> +++ b/drivers/iio/adc/ad7091r8.c
> @@ -0,0 +1,261 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Analog Devices AD7091R8 12-bit SAR ADC driver
> + *
> + * Copyright 2023 Analog Devices Inc.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/iio/iio.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/spi/spi.h>
> +
> +#include "ad7091r-base.h"
> +
> +#define AD7091R8_REG_ADDR_MSK GENMASK(15, 11)
> +#define AD7091R8_RD_WR_FLAG_MSK BIT(10)
> +#define AD7091R8_REG_DATA_MSK GENMASK(9, 0)
> +
> +#define AD7091R2_DEV_NAME "ad7091r-2"
> +#define AD7091R4_DEV_NAME "ad7091r-4"
> +#define AD7091R8_DEV_NAME "ad7091r-8"
Not seeing any advantage in these macros. It will be more readable to just
have the strings inline where the macros are currently used.
> +static int ad7091r8_gpio_setup(struct ad7091r_state *st)
> +{
> + st->convst_gpio = devm_gpiod_get(st->dev, "adi,conversion-start",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(st->convst_gpio))
> + return dev_err_probe(st->dev, PTR_ERR(st->convst_gpio),
> + "Error getting convst GPIO\n");
> +
> + st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(st->reset_gpio))
> + return PTR_ERR(st->reset_gpio);
Maybe a dev_err_probe() here as well both for consistency and for the
debug info that gets stashed if it's EPROBE_DEFER
> +
> + if (st->reset_gpio) {
> + fsleep(20);
> + gpiod_set_value_cansleep(st->reset_gpio, 0);
> + }
> +
> + return 0;
> +}
> +
> +static struct ad7091r_init_info ad7091r2_init_info = {
> + .info_no_irq = AD7091R_SPI_CHIP_INFO(2),
> + .regmap_config = &ad7091r2_reg_conf,
> + .ad7091r_regmap_init = &ad7091r8_regmap_init,
> + .ad7091r_setup = &ad7091r8_gpio_setup
> +};
> +
> +static struct ad7091r_init_info ad7091r4_init_info = {
> + .irq_info = AD7091R_SPI_CHIP_INFO_IRQ(4),
> + .info_no_irq = AD7091R_SPI_CHIP_INFO(4),
> + .regmap_config = &ad7091r4_reg_conf,
> + .ad7091r_regmap_init = &ad7091r8_regmap_init,
> + .ad7091r_setup = &ad7091r8_gpio_setup
> +};
> +
> +static struct ad7091r_init_info ad7091r8_init_info = {
> + .irq_info = AD7091R_SPI_CHIP_INFO_IRQ(8),
> + .info_no_irq = AD7091R_SPI_CHIP_INFO(8),
> + .regmap_config = &ad7091r8_reg_conf,
> + .ad7091r_regmap_init = &ad7091r8_regmap_init,
> + .ad7091r_setup = &ad7091r8_gpio_setup
> +};
> +
> +static int ad7091r8_spi_probe(struct spi_device *spi)
> +{
> + const struct spi_device_id *id = spi_get_device_id(spi);
> + const struct ad7091r_init_info *init_info;
> +
> + init_info = spi_get_device_match_data(spi);
> + if (!init_info)
> + return -EINVAL;
> +
> + return ad7091r_probe(&spi->dev, id->name, init_info, NULL, spi->irq);
id->name isn't generally a good idea because we end up with lots of odd corner
cases if the of_device_id and spi_device_id tables get out of sync - which
can happen if fallback compatibles get used.
Normal way round this is just put the naming of the device in the
info structure. Costs a little storage, but makes the code simpler
and less probe to odd corner cases. Also, I think you already have it
in there!
> +}
> +
> +static const struct of_device_id ad7091r8_of_match[] = {
> + { .compatible = "adi,ad7091r2", .data = &ad7091r2_init_info },
> + { .compatible = "adi,ad7091r4", .data = &ad7091r4_init_info },
> + { .compatible = "adi,ad7091r8", .data = &ad7091r8_init_info },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, ad7091r8_of_match);
> +
> +static const struct spi_device_id ad7091r8_spi_id[] = {
> + { "ad7091r2", (kernel_ulong_t)&ad7091r2_init_info },
> + { "ad7091r4", (kernel_ulong_t)&ad7091r4_init_info },
> + { "ad7091r8", (kernel_ulong_t)&ad7091r8_init_info },
> + {}
Trivial but be consistent on spacing for these terminators. I like a space, so
{ } but I don't mind if an author prefers {} as long as they are consistent!
> +};
> +MODULE_DEVICE_TABLE(spi, ad7091r8_spi_id);
