diff options
Diffstat (limited to 'drivers/iio/adc/axp288_adc.c')
| -rw-r--r-- | drivers/iio/adc/axp288_adc.c | 108 |
1 files changed, 92 insertions, 16 deletions
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c index 462a99c13e7a..546bbe59c241 100644 --- a/drivers/iio/adc/axp288_adc.c +++ b/drivers/iio/adc/axp288_adc.c @@ -16,6 +16,7 @@ * */ +#include <linux/dmi.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/device.h> @@ -27,9 +28,23 @@ #include <linux/iio/machine.h> #include <linux/iio/driver.h> -#define AXP288_ADC_EN_MASK 0xF1 -#define AXP288_ADC_TS_PIN_GPADC 0xF2 -#define AXP288_ADC_TS_PIN_ON 0xF3 +/* + * This mask enables all ADCs except for the battery temp-sensor (TS), that is + * left as-is to avoid breaking charging on devices without a temp-sensor. + */ +#define AXP288_ADC_EN_MASK 0xF0 +#define AXP288_ADC_TS_ENABLE 0x01 + +#define AXP288_ADC_TS_BIAS_MASK GENMASK(5, 4) +#define AXP288_ADC_TS_BIAS_20UA (0 << 4) +#define AXP288_ADC_TS_BIAS_40UA (1 << 4) +#define AXP288_ADC_TS_BIAS_60UA (2 << 4) +#define AXP288_ADC_TS_BIAS_80UA (3 << 4) +#define AXP288_ADC_TS_CURRENT_ON_OFF_MASK GENMASK(1, 0) +#define AXP288_ADC_TS_CURRENT_OFF (0 << 0) +#define AXP288_ADC_TS_CURRENT_ON_WHEN_CHARGING (1 << 0) +#define AXP288_ADC_TS_CURRENT_ON_ONDEMAND (2 << 0) +#define AXP288_ADC_TS_CURRENT_ON (3 << 0) enum axp288_adc_id { AXP288_ADC_TS, @@ -44,6 +59,7 @@ enum axp288_adc_id { struct axp288_adc_info { int irq; struct regmap *regmap; + bool ts_enabled; }; static const struct iio_chan_spec axp288_adc_channels[] = { @@ -123,21 +139,33 @@ static int axp288_adc_read_channel(int *val, unsigned long address, return IIO_VAL_INT; } -static int axp288_adc_set_ts(struct regmap *regmap, unsigned int mode, - unsigned long address) +/* + * The current-source used for the battery temp-sensor (TS) is shared + * with the GPADC. For proper fuel-gauge and charger operation the TS + * current-source needs to be permanently on. But to read the GPADC we + * need to temporary switch the TS current-source to ondemand, so that + * the GPADC can use it, otherwise we will always read an all 0 value. + */ +static int axp288_adc_set_ts(struct axp288_adc_info *info, + unsigned int mode, unsigned long address) { int ret; - /* channels other than GPADC do not need to switch TS pin */ + /* No need to switch the current-source if the TS pin is disabled */ + if (!info->ts_enabled) + return 0; + + /* Channels other than GPADC do not need the current source */ if (address != AXP288_GP_ADC_H) return 0; - ret = regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, mode); + ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_CURRENT_ON_OFF_MASK, mode); if (ret) return ret; /* When switching to the GPADC pin give things some time to settle */ - if (mode == AXP288_ADC_TS_PIN_GPADC) + if (mode == AXP288_ADC_TS_CURRENT_ON_ONDEMAND) usleep_range(6000, 10000); return 0; @@ -153,14 +181,14 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev, mutex_lock(&indio_dev->mlock); switch (mask) { case IIO_CHAN_INFO_RAW: - if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_GPADC, + if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON_ONDEMAND, chan->address)) { dev_err(&indio_dev->dev, "GPADC mode\n"); ret = -EINVAL; break; } ret = axp288_adc_read_channel(val, chan->address, info->regmap); - if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_ON, + if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON, chan->address)) dev_err(&indio_dev->dev, "TS pin restore\n"); break; @@ -172,13 +200,61 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev, return ret; } -static int axp288_adc_set_state(struct regmap *regmap) +/* + * We rely on the machine's firmware to correctly setup the TS pin bias current + * at boot. This lists systems with broken fw where we need to set it ourselves. + */ +static const struct dmi_system_id axp288_adc_ts_bias_override[] = { + { + /* Lenovo Ideapad 100S (11 inch) */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo ideapad 100S-11IBY"), + }, + .driver_data = (void *)(uintptr_t)AXP288_ADC_TS_BIAS_80UA, + }, + {} +}; + +static int axp288_adc_initialize(struct axp288_adc_info *info) { - /* ADC should be always enabled for internal FG to function */ - if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON)) - return -EIO; + const struct dmi_system_id *bias_override; + int ret, adc_enable_val; + + bias_override = dmi_first_match(axp288_adc_ts_bias_override); + if (bias_override) { + ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_BIAS_MASK, + (uintptr_t)bias_override->driver_data); + if (ret) + return ret; + } + + /* + * Determine if the TS pin is enabled and set the TS current-source + * accordingly. + */ + ret = regmap_read(info->regmap, AXP20X_ADC_EN1, &adc_enable_val); + if (ret) + return ret; + + if (adc_enable_val & AXP288_ADC_TS_ENABLE) { + info->ts_enabled = true; + ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_CURRENT_ON_OFF_MASK, + AXP288_ADC_TS_CURRENT_ON); + } else { + info->ts_enabled = false; + ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL, + AXP288_ADC_TS_CURRENT_ON_OFF_MASK, + AXP288_ADC_TS_CURRENT_OFF); + } + if (ret) + return ret; - return regmap_write(regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK); + /* Turn on the ADC for all channels except TS, leave TS as is */ + return regmap_update_bits(info->regmap, AXP20X_ADC_EN1, + AXP288_ADC_EN_MASK, AXP288_ADC_EN_MASK); } static const struct iio_info axp288_adc_iio_info = { @@ -209,7 +285,7 @@ static int axp288_adc_probe(struct platform_device *pdev) * Set ADC to enabled state at all time, including system suspend. * otherwise internal fuel gauge functionality may be affected. */ - ret = axp288_adc_set_state(axp20x->regmap); + ret = axp288_adc_initialize(info); if (ret) { dev_err(&pdev->dev, "unable to enable ADC device\n"); return ret; |