diff options
Diffstat (limited to 'drivers/iio/adc')
| -rw-r--r-- | drivers/iio/adc/ingenic-adc.c | 54 | ||||
| -rw-r--r-- | drivers/iio/adc/max9611.c | 4 | ||||
| -rw-r--r-- | drivers/iio/adc/rcar-gyroadc.c | 4 |
3 files changed, 58 insertions, 4 deletions
diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c index 92b1d5037ac9..e234970b7150 100644 --- a/drivers/iio/adc/ingenic-adc.c +++ b/drivers/iio/adc/ingenic-adc.c @@ -11,6 +11,7 @@ #include <linux/iio/iio.h> #include <linux/io.h> #include <linux/iopoll.h> +#include <linux/kernel.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/platform_device.h> @@ -22,8 +23,11 @@ #define JZ_ADC_REG_ADTCH 0x18 #define JZ_ADC_REG_ADBDAT 0x1c #define JZ_ADC_REG_ADSDAT 0x20 +#define JZ_ADC_REG_ADCLK 0x28 #define JZ_ADC_REG_CFG_BAT_MD BIT(4) +#define JZ_ADC_REG_ADCLK_CLKDIV_LSB 0 +#define JZ_ADC_REG_ADCLK_CLKDIV10US_LSB 16 #define JZ_ADC_AUX_VREF 3300 #define JZ_ADC_AUX_VREF_BITS 12 @@ -34,6 +38,8 @@ #define JZ4740_ADC_BATTERY_HIGH_VREF (7500 * 0.986) #define JZ4740_ADC_BATTERY_HIGH_VREF_BITS 12 +struct ingenic_adc; + struct ingenic_adc_soc_data { unsigned int battery_high_vref; unsigned int battery_high_vref_bits; @@ -41,6 +47,7 @@ struct ingenic_adc_soc_data { size_t battery_raw_avail_size; const int *battery_scale_avail; size_t battery_scale_avail_size; + int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc); }; struct ingenic_adc { @@ -151,6 +158,42 @@ static const int jz4740_adc_battery_scale_avail[] = { JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS, }; +static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc) +{ + struct clk *parent_clk; + unsigned long parent_rate, rate; + unsigned int div_main, div_10us; + + parent_clk = clk_get_parent(adc->clk); + if (!parent_clk) { + dev_err(dev, "ADC clock has no parent\n"); + return -ENODEV; + } + parent_rate = clk_get_rate(parent_clk); + + /* + * The JZ4725B ADC works at 500 kHz to 8 MHz. + * We pick the highest rate possible. + * In practice we typically get 6 MHz, half of the 12 MHz EXT clock. + */ + div_main = DIV_ROUND_UP(parent_rate, 8000000); + div_main = clamp(div_main, 1u, 64u); + rate = parent_rate / div_main; + if (rate < 500000 || rate > 8000000) { + dev_err(dev, "No valid divider for ADC main clock\n"); + return -EINVAL; + } + + /* We also need a divider that produces a 10us clock. */ + div_10us = DIV_ROUND_UP(rate, 100000); + + writel(((div_10us - 1) << JZ_ADC_REG_ADCLK_CLKDIV10US_LSB) | + (div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB, + adc->base + JZ_ADC_REG_ADCLK); + + return 0; +} + static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = { .battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF, .battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS, @@ -158,6 +201,7 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = { .battery_raw_avail_size = ARRAY_SIZE(jz4725b_adc_battery_raw_avail), .battery_scale_avail = jz4725b_adc_battery_scale_avail, .battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail), + .init_clk_div = jz4725b_adc_init_clk_div, }; static const struct ingenic_adc_soc_data jz4740_adc_soc_data = { @@ -167,6 +211,7 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = { .battery_raw_avail_size = ARRAY_SIZE(jz4740_adc_battery_raw_avail), .battery_scale_avail = jz4740_adc_battery_scale_avail, .battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail), + .init_clk_div = NULL, /* no ADCLK register on JZ4740 */ }; static int ingenic_adc_read_avail(struct iio_dev *iio_dev, @@ -317,6 +362,15 @@ static int ingenic_adc_probe(struct platform_device *pdev) return ret; } + /* Set clock dividers. */ + if (soc_data->init_clk_div) { + ret = soc_data->init_clk_div(dev, adc); + if (ret) { + clk_disable_unprepare(adc->clk); + return ret; + } + } + /* Put hardware in a known passive state. */ writeb(0x00, adc->base + JZ_ADC_REG_ENABLE); writeb(0xff, adc->base + JZ_ADC_REG_CTRL); diff --git a/drivers/iio/adc/max9611.c b/drivers/iio/adc/max9611.c index 917223d5ff5b..da073d72f649 100644 --- a/drivers/iio/adc/max9611.c +++ b/drivers/iio/adc/max9611.c @@ -83,7 +83,7 @@ #define MAX9611_TEMP_MAX_POS 0x7f80 #define MAX9611_TEMP_MAX_NEG 0xff80 #define MAX9611_TEMP_MIN_NEG 0xd980 -#define MAX9611_TEMP_MASK GENMASK(7, 15) +#define MAX9611_TEMP_MASK GENMASK(15, 7) #define MAX9611_TEMP_SHIFT 0x07 #define MAX9611_TEMP_RAW(_r) ((_r) >> MAX9611_TEMP_SHIFT) #define MAX9611_TEMP_SCALE_NUM 1000000 @@ -480,7 +480,7 @@ static int max9611_init(struct max9611_dev *max9611) if (ret) return ret; - regval = ret & MAX9611_TEMP_MASK; + regval &= MAX9611_TEMP_MASK; if ((regval > MAX9611_TEMP_MAX_POS && regval < MAX9611_TEMP_MIN_NEG) || diff --git a/drivers/iio/adc/rcar-gyroadc.c b/drivers/iio/adc/rcar-gyroadc.c index 2d685730f867..c37f201294b2 100644 --- a/drivers/iio/adc/rcar-gyroadc.c +++ b/drivers/iio/adc/rcar-gyroadc.c @@ -382,7 +382,7 @@ static int rcar_gyroadc_parse_subdevs(struct iio_dev *indio_dev) dev_err(dev, "Only %i channels supported with %pOFn, but reg = <%i>.\n", num_channels, child, reg); - return ret; + return -EINVAL; } } @@ -391,7 +391,7 @@ static int rcar_gyroadc_parse_subdevs(struct iio_dev *indio_dev) dev_err(dev, "Channel %i uses different ADC mode than the rest.\n", reg); - return ret; + return -EINVAL; } /* Channel is valid, grab the regulator. */ |