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-rw-r--r--drivers/iio/adc/axp288_adc.c319
1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
new file mode 100644
index 0000000000..49fff1cabd
--- /dev/null
+++ b/drivers/iio/adc/axp288_adc.c
@@ -0,0 +1,319 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
+ *
+ * Copyright (C) 2014 Intel Corporation
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/dmi.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/platform_device.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/machine.h>
+#include <linux/iio/driver.h>
+
+/*
+ * 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,
+ AXP288_ADC_PMIC,
+ AXP288_ADC_GP,
+ AXP288_ADC_BATT_CHRG_I,
+ AXP288_ADC_BATT_DISCHRG_I,
+ AXP288_ADC_BATT_V,
+ AXP288_ADC_NR_CHAN,
+};
+
+struct axp288_adc_info {
+ int irq;
+ struct regmap *regmap;
+ /* lock to protect against multiple access to the device */
+ struct mutex lock;
+ bool ts_enabled;
+};
+
+static const struct iio_chan_spec axp288_adc_channels[] = {
+ {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 0,
+ .address = AXP288_TS_ADC_H,
+ .datasheet_name = "TS_PIN",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 1,
+ .address = AXP288_PMIC_ADC_H,
+ .datasheet_name = "PMIC_TEMP",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 2,
+ .address = AXP288_GP_ADC_H,
+ .datasheet_name = "GPADC",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .indexed = 1,
+ .type = IIO_CURRENT,
+ .channel = 3,
+ .address = AXP20X_BATT_CHRG_I_H,
+ .datasheet_name = "BATT_CHG_I",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .indexed = 1,
+ .type = IIO_CURRENT,
+ .channel = 4,
+ .address = AXP20X_BATT_DISCHRG_I_H,
+ .datasheet_name = "BATT_DISCHRG_I",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }, {
+ .indexed = 1,
+ .type = IIO_VOLTAGE,
+ .channel = 5,
+ .address = AXP20X_BATT_V_H,
+ .datasheet_name = "BATT_V",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ },
+};
+
+/* for consumer drivers */
+static struct iio_map axp288_adc_default_maps[] = {
+ IIO_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
+ IIO_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
+ IIO_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
+ IIO_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
+ IIO_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
+ IIO_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
+ {},
+};
+
+static int axp288_adc_read_channel(int *val, unsigned long address,
+ struct regmap *regmap)
+{
+ u8 buf[2];
+
+ if (regmap_bulk_read(regmap, address, buf, 2))
+ return -EIO;
+ *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);
+
+ return IIO_VAL_INT;
+}
+
+/*
+ * 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;
+
+ /* 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_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_CURRENT_ON_ONDEMAND)
+ usleep_range(6000, 10000);
+
+ return 0;
+}
+
+static int axp288_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ struct axp288_adc_info *info = iio_priv(indio_dev);
+
+ mutex_lock(&info->lock);
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ 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, AXP288_ADC_TS_CURRENT_ON,
+ chan->address))
+ dev_err(&indio_dev->dev, "TS pin restore\n");
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ mutex_unlock(&info->lock);
+
+ return ret;
+}
+
+/*
+ * 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,
+ },
+ {
+ /* Nuvision Solo 10 Draw */
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TMAX"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "TM101W610L"),
+ },
+ .driver_data = (void *)(uintptr_t)AXP288_ADC_TS_BIAS_80UA,
+ },
+ {}
+};
+
+static int axp288_adc_initialize(struct axp288_adc_info *info)
+{
+ 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;
+
+ /* 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 = {
+ .read_raw = &axp288_adc_read_raw,
+};
+
+static int axp288_adc_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct axp288_adc_info *info;
+ struct iio_dev *indio_dev;
+ struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ info = iio_priv(indio_dev);
+ info->irq = platform_get_irq(pdev, 0);
+ if (info->irq < 0)
+ return info->irq;
+
+ info->regmap = axp20x->regmap;
+ /*
+ * Set ADC to enabled state at all time, including system suspend.
+ * otherwise internal fuel gauge functionality may be affected.
+ */
+ ret = axp288_adc_initialize(info);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to enable ADC device\n");
+ return ret;
+ }
+
+ indio_dev->name = pdev->name;
+ indio_dev->channels = axp288_adc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
+ indio_dev->info = &axp288_adc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = devm_iio_map_array_register(&pdev->dev, indio_dev, axp288_adc_default_maps);
+ if (ret < 0)
+ return ret;
+
+ mutex_init(&info->lock);
+
+ return devm_iio_device_register(&pdev->dev, indio_dev);
+}
+
+static const struct platform_device_id axp288_adc_id_table[] = {
+ { .name = "axp288_adc" },
+ {},
+};
+
+static struct platform_driver axp288_adc_driver = {
+ .probe = axp288_adc_probe,
+ .id_table = axp288_adc_id_table,
+ .driver = {
+ .name = "axp288_adc",
+ },
+};
+
+MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);
+
+module_platform_driver(axp288_adc_driver);
+
+MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
+MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
+MODULE_LICENSE("GPL");