This makes use of the new devm_regulator_get_enable_read_voltage() helper function to reduce boilerplate code in the MCP3564 ADC driver. The error message is slightly changed since there are fewer error return paths. Setting adc->vref_mv is consolidated into a single place to make the logic easier to follow. A use_internal_vref_attr local variable is added to make it more obvious what the difference between the two iio info structures is. The return value of the "Unknown Vref" dev_err_probe() is hard-coded to -ENODEV instead of ret since it was getting a bit far from where ret was set and logically that is the only value it could have. Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx> --- v2 changes: * Rename use_auto_zeroing_ref_attr to use_internal_vref_attr * Link to v1: https://lore.kernel.org/r/20240712-iio-regulator-refactor-round-3-v1-0-835017bae43d@xxxxxxxxxxxx (other patches from v1 were already applied, so not included in v2) --- drivers/iio/adc/mcp3564.c | 54 ++++++++++++++--------------------------------- 1 file changed, 16 insertions(+), 38 deletions(-) diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c index d83bed0e63d2..a68f1cd6883e 100644 --- a/drivers/iio/adc/mcp3564.c +++ b/drivers/iio/adc/mcp3564.c @@ -349,8 +349,6 @@ struct mcp3564_chip_info { * struct mcp3564_state - working data for a ADC device * @chip_info: chip specific data * @spi: SPI device structure - * @vref: the regulator device used as a voltage reference in case - * external voltage reference is used * @vref_mv: voltage reference value in miliVolts * @lock: synchronize access to driver's state members * @dev_addr: hardware device address @@ -369,7 +367,6 @@ struct mcp3564_chip_info { struct mcp3564_state { const struct mcp3564_chip_info *chip_info; struct spi_device *spi; - struct regulator *vref; unsigned short vref_mv; struct mutex lock; /* Synchronize access to driver's state members */ u8 dev_addr; @@ -1085,11 +1082,6 @@ static int mcp3564_parse_fw_children(struct iio_dev *indio_dev) return 0; } -static void mcp3564_disable_reg(void *reg) -{ - regulator_disable(reg); -} - static void mcp3564_fill_scale_tbls(struct mcp3564_state *adc) { unsigned int pow = adc->chip_info->resolution - 1; @@ -1110,7 +1102,7 @@ static void mcp3564_fill_scale_tbls(struct mcp3564_state *adc) } } -static int mcp3564_config(struct iio_dev *indio_dev) +static int mcp3564_config(struct iio_dev *indio_dev, bool *use_internal_vref_attr) { struct mcp3564_state *adc = iio_priv(indio_dev); struct device *dev = &adc->spi->dev; @@ -1119,6 +1111,7 @@ static int mcp3564_config(struct iio_dev *indio_dev) enum mcp3564_ids ids; int ret = 0; unsigned int tmp = 0x01; + bool internal_vref; bool err = false; /* @@ -1218,36 +1211,22 @@ static int mcp3564_config(struct iio_dev *indio_dev) dev_dbg(dev, "Found %s chip\n", adc->chip_info->name); - adc->vref = devm_regulator_get_optional(dev, "vref"); - if (IS_ERR(adc->vref)) { - if (PTR_ERR(adc->vref) != -ENODEV) - return dev_err_probe(dev, PTR_ERR(adc->vref), - "failed to get regulator\n"); + ret = devm_regulator_get_enable_read_voltage(dev, "vref"); + if (ret < 0 && ret != -ENODEV) + return dev_err_probe(dev, ret, "Failed to get vref voltage\n"); + + internal_vref = ret == -ENODEV; + adc->vref_mv = internal_vref ? MCP3564R_INT_VREF_MV : ret / MILLI; + *use_internal_vref_attr = internal_vref; + if (internal_vref) { /* Check if chip has internal vref */ if (!adc->have_vref) - return dev_err_probe(dev, PTR_ERR(adc->vref), - "Unknown Vref\n"); - adc->vref = NULL; + return dev_err_probe(dev, -ENODEV, "Unknown Vref\n"); + dev_dbg(dev, "%s: Using internal Vref\n", __func__); } else { - ret = regulator_enable(adc->vref); - if (ret) - return ret; - - ret = devm_add_action_or_reset(dev, mcp3564_disable_reg, - adc->vref); - if (ret) - return ret; - dev_dbg(dev, "%s: Using External Vref\n", __func__); - - ret = regulator_get_voltage(adc->vref); - if (ret < 0) - return dev_err_probe(dev, ret, - "Failed to read vref regulator\n"); - - adc->vref_mv = ret / MILLI; } ret = mcp3564_parse_fw_children(indio_dev); @@ -1350,10 +1329,8 @@ static int mcp3564_config(struct iio_dev *indio_dev) tmp_reg |= FIELD_PREP(MCP3564_CONFIG0_CLK_SEL_MASK, MCP3564_CONFIG0_USE_INT_CLK); tmp_reg |= MCP3456_CONFIG0_BIT6_DEFAULT; - if (!adc->vref) { + if (internal_vref) tmp_reg |= FIELD_PREP(MCP3456_CONFIG0_VREF_MASK, 1); - adc->vref_mv = MCP3564R_INT_VREF_MV; - } ret = mcp3564_write_8bits(adc, MCP3564_CONFIG0_REG, tmp_reg); @@ -1412,6 +1389,7 @@ static int mcp3564_probe(struct spi_device *spi) int ret; struct iio_dev *indio_dev; struct mcp3564_state *adc; + bool use_internal_vref_attr; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); if (!indio_dev) @@ -1428,7 +1406,7 @@ static int mcp3564_probe(struct spi_device *spi) * enable/disable certain channels * change the sampling rate to the requested value */ - ret = mcp3564_config(indio_dev); + ret = mcp3564_config(indio_dev, &use_internal_vref_attr); if (ret) return dev_err_probe(&spi->dev, ret, "Can't configure MCP356X device\n"); @@ -1440,7 +1418,7 @@ static int mcp3564_probe(struct spi_device *spi) indio_dev->name = adc->chip_info->name; indio_dev->modes = INDIO_DIRECT_MODE; - if (!adc->vref) + if (use_internal_vref_attr) indio_dev->info = &mcp3564r_info; else indio_dev->info = &mcp3564_info; --- base-commit: 472438c7e0e2261c6737a8321f46ef176eef1c8f change-id: 20240712-iio-regulator-refactor-round-3-17f2a82d2181
