diff options
Diffstat (limited to 'drivers/iio/adc/ad7192.c')
| -rw-r--r-- | drivers/iio/adc/ad7192.c | 189 |
1 files changed, 158 insertions, 31 deletions
diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c index 334ab90991d4..7042ddfdfc03 100644 --- a/drivers/iio/adc/ad7192.c +++ b/drivers/iio/adc/ad7192.c @@ -8,6 +8,7 @@ #include <linux/interrupt.h> #include <linux/bitfield.h> #include <linux/clk.h> +#include <linux/clk-provider.h> #include <linux/device.h> #include <linux/kernel.h> #include <linux/slab.h> @@ -201,6 +202,7 @@ struct ad7192_chip_info { struct ad7192_state { const struct ad7192_chip_info *chip_info; struct clk *mclk; + struct clk_hw int_clk_hw; u16 int_vref_mv; u32 aincom_mv; u32 fclk; @@ -284,7 +286,7 @@ static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = { &ad7192_syscalib_mode_enum), IIO_ENUM_AVAILABLE("sys_calibration_mode", IIO_SHARED_BY_TYPE, &ad7192_syscalib_mode_enum), - {} + { } }; static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd) @@ -396,25 +398,162 @@ static inline bool ad7192_valid_external_frequency(u32 freq) freq <= AD7192_EXT_FREQ_MHZ_MAX); } -static int ad7192_clock_select(struct ad7192_state *st) +/* + * Position 0 of ad7192_clock_names, xtal, corresponds to clock source + * configuration AD7192_CLK_EXT_MCLK1_2 and position 1, mclk, corresponds to + * AD7192_CLK_EXT_MCLK2 + */ +static const char *const ad7192_clock_names[] = { + "xtal", + "mclk" +}; + +static struct ad7192_state *clk_hw_to_ad7192(struct clk_hw *hw) +{ + return container_of(hw, struct ad7192_state, int_clk_hw); +} + +static unsigned long ad7192_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return AD7192_INT_FREQ_MHZ; +} + +static int ad7192_clk_output_is_enabled(struct clk_hw *hw) +{ + struct ad7192_state *st = clk_hw_to_ad7192(hw); + + return st->clock_sel == AD7192_CLK_INT_CO; +} + +static int ad7192_clk_prepare(struct clk_hw *hw) +{ + struct ad7192_state *st = clk_hw_to_ad7192(hw); + int ret; + + st->mode &= ~AD7192_MODE_CLKSRC_MASK; + st->mode |= AD7192_CLK_INT_CO; + + ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + if (ret) + return ret; + + st->clock_sel = AD7192_CLK_INT_CO; + + return 0; +} + +static void ad7192_clk_unprepare(struct clk_hw *hw) +{ + struct ad7192_state *st = clk_hw_to_ad7192(hw); + int ret; + + st->mode &= ~AD7192_MODE_CLKSRC_MASK; + st->mode |= AD7192_CLK_INT; + + ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + if (ret) + return; + + st->clock_sel = AD7192_CLK_INT; +} + +static const struct clk_ops ad7192_int_clk_ops = { + .recalc_rate = ad7192_clk_recalc_rate, + .is_enabled = ad7192_clk_output_is_enabled, + .prepare = ad7192_clk_prepare, + .unprepare = ad7192_clk_unprepare, +}; + +static int ad7192_register_clk_provider(struct ad7192_state *st) { struct device *dev = &st->sd.spi->dev; - unsigned int clock_sel; + struct clk_init_data init = {}; + int ret; - clock_sel = AD7192_CLK_INT; + if (!IS_ENABLED(CONFIG_COMMON_CLK)) + return 0; - /* use internal clock */ - if (!st->mclk) { - if (device_property_read_bool(dev, "adi,int-clock-output-enable")) - clock_sel = AD7192_CLK_INT_CO; - } else { - if (device_property_read_bool(dev, "adi,clock-xtal")) - clock_sel = AD7192_CLK_EXT_MCLK1_2; - else - clock_sel = AD7192_CLK_EXT_MCLK2; + if (!device_property_present(dev, "#clock-cells")) + return 0; + + init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk", + fwnode_get_name(dev_fwnode(dev))); + if (!init.name) + return -ENOMEM; + + init.ops = &ad7192_int_clk_ops; + + st->int_clk_hw.init = &init; + ret = devm_clk_hw_register(dev, &st->int_clk_hw); + if (ret) + return ret; + + return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, + &st->int_clk_hw); +} + +static int ad7192_clock_setup(struct ad7192_state *st) +{ + struct device *dev = &st->sd.spi->dev; + int ret; + + /* + * The following two if branches are kept for backward compatibility but + * the use of the two devicetree properties is highly discouraged. Clock + * configuration should be done according to the bindings. + */ + + if (device_property_read_bool(dev, "adi,int-clock-output-enable")) { + st->clock_sel = AD7192_CLK_INT_CO; + st->fclk = AD7192_INT_FREQ_MHZ; + dev_warn(dev, "Property adi,int-clock-output-enable is deprecated! Check bindings!\n"); + return 0; + } + + if (device_property_read_bool(dev, "adi,clock-xtal")) { + st->clock_sel = AD7192_CLK_EXT_MCLK1_2; + st->mclk = devm_clk_get_enabled(dev, "mclk"); + if (IS_ERR(st->mclk)) + return dev_err_probe(dev, PTR_ERR(st->mclk), + "Failed to get mclk\n"); + + st->fclk = clk_get_rate(st->mclk); + if (!ad7192_valid_external_frequency(st->fclk)) + return dev_err_probe(dev, -EINVAL, + "External clock frequency out of bounds\n"); + + dev_warn(dev, "Property adi,clock-xtal is deprecated! Check bindings!\n"); + return 0; + } + + ret = device_property_match_property_string(dev, "clock-names", + ad7192_clock_names, + ARRAY_SIZE(ad7192_clock_names)); + if (ret < 0) { + st->clock_sel = AD7192_CLK_INT; + st->fclk = AD7192_INT_FREQ_MHZ; + + ret = ad7192_register_clk_provider(st); + if (ret) + return dev_err_probe(dev, ret, + "Failed to register clock provider\n"); + return 0; } - return clock_sel; + st->clock_sel = AD7192_CLK_EXT_MCLK1_2 + ret; + + st->mclk = devm_clk_get_enabled(dev, ad7192_clock_names[ret]); + if (IS_ERR(st->mclk)) + return dev_err_probe(dev, PTR_ERR(st->mclk), + "Failed to get clock source\n"); + + st->fclk = clk_get_rate(st->mclk); + if (!ad7192_valid_external_frequency(st->fclk)) + return dev_err_probe(dev, -EINVAL, + "External clock frequency out of bounds\n"); + + return 0; } static int ad7192_setup(struct iio_dev *indio_dev, struct device *dev) @@ -1275,21 +1414,9 @@ static int ad7192_probe(struct spi_device *spi) if (ret) return ret; - st->fclk = AD7192_INT_FREQ_MHZ; - - st->mclk = devm_clk_get_optional_enabled(dev, "mclk"); - if (IS_ERR(st->mclk)) - return PTR_ERR(st->mclk); - - st->clock_sel = ad7192_clock_select(st); - - if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 || - st->clock_sel == AD7192_CLK_EXT_MCLK2) { - st->fclk = clk_get_rate(st->mclk); - if (!ad7192_valid_external_frequency(st->fclk)) - return dev_err_probe(dev, -EINVAL, - "External clock frequency out of bounds\n"); - } + ret = ad7192_clock_setup(st); + if (ret) + return ret; ret = ad7192_setup(indio_dev, dev); if (ret) @@ -1304,7 +1431,7 @@ static const struct of_device_id ad7192_of_match[] = { { .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] }, { .compatible = "adi,ad7194", .data = &ad7192_chip_info_tbl[ID_AD7194] }, { .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] }, - {} + { } }; MODULE_DEVICE_TABLE(of, ad7192_of_match); @@ -1314,7 +1441,7 @@ static const struct spi_device_id ad7192_ids[] = { { "ad7193", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7193] }, { "ad7194", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7194] }, { "ad7195", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7195] }, - {} + { } }; MODULE_DEVICE_TABLE(spi, ad7192_ids); |