[PATCH] iio: adc: mt6360: Add ADC driver for MT6360

From: Gene Chen
Date: Wed Jun 03 2020 - 23:00:42 EST

From: Gene Chen <gene_chen@xxxxxxxxxxx>

Add MT6360 ADC driver include Charger Current, Voltage, and
Temperature.

Signed-off-by: Gene Chen <gene_chen@xxxxxxxxxxx>
base-commit: 098c4adf249c198519a4abebe482b1e6b8c50e47
---
drivers/iio/adc/Kconfig | 11 ++
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/mt6360-adc.c | 419 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 431 insertions(+)
create mode 100644 drivers/iio/adc/mt6360-adc.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 12bb8b7..a9736ec 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -657,6 +657,17 @@ config MCP3911
This driver can also be built as a module. If so, the module will be
called mcp3911.

+config MEDIATEK_MT6360_ADC
+ tristate "Mediatek MT6360 ADC Part"
+ depends on MFD_MT6360
+ select IIO_BUFFER
+ select IIO_KFIFO_BUF
+ help
+ Say Y here to enable MT6360 ADC Part.
+ Integrated for System Monitoring include
+ Charger and Battery Current, Voltage and
+ Terperature
+
config MEDIATEK_MT6577_AUXADC
tristate "MediaTek AUXADC driver"
depends on ARCH_MEDIATEK || COMPILE_TEST
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 6378078..4209776 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_MAX9611) += max9611.o
obj-$(CONFIG_MCP320X) += mcp320x.o
obj-$(CONFIG_MCP3422) += mcp3422.o
obj-$(CONFIG_MCP3911) += mcp3911.o
+obj-$(CONFIG_MEDIATEK_MT6360_ADC) += mt6360-adc.o
obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) += mt6577_auxadc.o
obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
obj-$(CONFIG_MESON_SARADC) += meson_saradc.o
diff --git a/drivers/iio/adc/mt6360-adc.c b/drivers/iio/adc/mt6360-adc.c
new file mode 100644
index 0000000..bc9c488
--- /dev/null
+++ b/drivers/iio/adc/mt6360-adc.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020 MediaTek Inc.
+ *
+ * Author: Gene Chen <gene_chen@xxxxxxxxxxx>
+ */
+
+#include <linux/completion.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/mt6360.h>
+
+/* CHG_CTRL3 0x13 */
+#define MT6360_AICR_MASK (0xFC)
+#define MT6360_AICR_SHFT (2)
+#define MT6360_AICR_400MA (0x6)
+/* ADC_CONFIG 0x56 */
+#define MT6360_ADCEN_SHFT (7)
+/* ADC_RPT_1 0x5A */
+#define MT6360_PREFERCH_MASK (0xF0)
+#define MT6360_PREFERCH_SHFT (4)
+#define MT6360_RPTCH_MASK (0x0F)
+
+enum {
+ MT6360_CHAN_USBID = 0,
+ MT6360_CHAN_VBUSDIV5,
+ MT6360_CHAN_VBUSDIV2,
+ MT6360_CHAN_VSYS,
+ MT6360_CHAN_VBAT,
+ MT6360_CHAN_IBUS,
+ MT6360_CHAN_IBAT,
+ MT6360_CHAN_CHG_VDDP,
+ MT6360_CHAN_TEMP_JC,
+ MT6360_CHAN_VREF_TS,
+ MT6360_CHAN_TS,
+ MT6360_CHAN_MAX,
+};
+
+struct mt6360_adc_data {
+ struct device *dev;
+ struct regmap *regmap;
+ struct task_struct *scan_task;
+ struct completion adc_complete;
+ struct mutex adc_lock;
+ ktime_t last_off_timestamps[MT6360_CHAN_MAX];
+ int irq;
+};
+
+static inline int mt6360_adc_val_converte(int val, int multiplier,
+ int offset, int divisor)
+{
+ return ((val * multiplier) + offset) / divisor;
+}
+
+static int mt6360_adc_get_process_val(struct mt6360_adc_data *info,
+ int chan_idx, int *val)
+{
+ unsigned int regval = 0;
+ int ret;
+ const struct converter {
+ int multiplier;
+ int offset;
+ int divisor;
+ } adc_converter[MT6360_CHAN_MAX] = {
+ { 1250, 0, 1}, /* USBID */
+ { 6250, 0, 1}, /* VBUSDIV5 */
+ { 2500, 0, 1}, /* VBUSDIV2 */
+ { 1250, 0, 1}, /* VSYS */
+ { 1250, 0, 1}, /* VBAT */
+ { 2500, 0, 1}, /* IBUS */
+ { 2500, 0, 1}, /* IBAT */
+ { 1250, 0, 1}, /* CHG_VDDP */
+ { 105, -8000, 100}, /* TEMP_JC */
+ { 1250, 0, 1}, /* VREF_TS */
+ { 1250, 0, 1}, /* TS */
+ }, sp_ibus_adc_converter = { 1900, 0, 1 }, *sel_converter;
+
+ if (chan_idx < 0 || chan_idx >= MT6360_CHAN_MAX)
+ return -EINVAL;
+ sel_converter = adc_converter + chan_idx;
+ if (chan_idx == MT6360_CHAN_IBUS) {
+ /* ibus chan will be affected by aicr config */
+ /* if aicr < 400, apply the special ibus converter */
+ ret = regmap_read(info->regmap, MT6360_PMU_CHG_CTRL3, &regval);
+ if (ret < 0)
+ return ret;
+ regval = (regval & MT6360_AICR_MASK) >> MT6360_AICR_SHFT;
+ if (regval < MT6360_AICR_400MA)
+ sel_converter = &sp_ibus_adc_converter;
+ }
+ *val = mt6360_adc_val_converte(*val, sel_converter->multiplier,
+ sel_converter->offset, sel_converter->divisor);
+ return 0;
+}
+
+static int mt6360_adc_read_raw(struct iio_dev *iio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long mask)
+{
+ struct mt6360_adc_data *mad = iio_priv(iio_dev);
+ long timeout;
+ u8 tmp[2], rpt[3];
+ ktime_t start_t, predict_end_t;
+ int ret;
+
+ mutex_lock(&mad->adc_lock);
+ /* select preferred channel that we want */
+ ret = regmap_update_bits(mad->regmap,
+ MT6360_PMU_ADC_RPT_1, MT6360_PREFERCH_MASK,
+ chan->channel << MT6360_PREFERCH_SHFT);
+ if (ret < 0)
+ goto err_adc_init;
+ /* enable adc channel we want and adc_en */
+ memset(tmp, 0, sizeof(tmp));
+ tmp[0] |= BIT(MT6360_ADCEN_SHFT);
+ tmp[(chan->channel / 8) ? 0 : 1] |= BIT(chan->channel % 8);
+ ret = regmap_bulk_write(mad->regmap,
+ MT6360_PMU_ADC_CONFIG, tmp, sizeof(tmp));
+ if (ret < 0)
+ goto err_adc_init;
+ start_t = ktime_get();
+ predict_end_t = ktime_add_ms(
+ mad->last_off_timestamps[chan->channel], 50);
+ if (ktime_after(start_t, predict_end_t))
+ predict_end_t = ktime_add_ms(start_t, 25);
+ else
+ predict_end_t = ktime_add_ms(start_t, 75);
+ enable_irq(mad->irq);
+retry:
+ reinit_completion(&mad->adc_complete);
+ /* wait for conversion to complete */
+ timeout = wait_for_completion_interruptible_timeout(
+ &mad->adc_complete, msecs_to_jiffies(200));
+ if (timeout == 0) {
+ ret = -ETIMEDOUT;
+ goto err_adc_conv;
+ } else if (timeout < 0) {
+ ret = -EINTR;
+ goto err_adc_conv;
+ }
+ memset(rpt, 0, sizeof(rpt));
+ ret = regmap_bulk_read(mad->regmap,
+ MT6360_PMU_ADC_RPT_1, rpt, sizeof(rpt));
+ if (ret < 0)
+ goto err_adc_conv;
+ /* get report channel */
+ if ((rpt[0] & MT6360_RPTCH_MASK) != chan->channel) {
+ dev_dbg(&iio_dev->dev,
+ "not wanted channel report [%02x]\n", rpt[0]);
+ goto retry;
+ }
+ if (!ktime_after(ktime_get(), predict_end_t)) {
+ dev_dbg(&iio_dev->dev, "time is not after 26ms chan_time\n");
+ goto retry;
+ }
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ *val = (rpt[1] << 8) | rpt[2];
+ break;
+ case IIO_CHAN_INFO_PROCESSED:
+ *val = (rpt[1] << 8) | rpt[2];
+ ret = mt6360_adc_get_process_val(mad, chan->channel, val);
+ if (ret < 0)
+ goto err_adc_conv;
+ break;
+ default:
+ break;
+ }
+ ret = IIO_VAL_INT;
+err_adc_conv:
+ disable_irq(mad->irq);
+ /* whatever disable all channel and keep adc_en*/
+ memset(tmp, 0, sizeof(tmp));
+ tmp[0] |= BIT(MT6360_ADCEN_SHFT);
+ regmap_bulk_write(mad->regmap, MT6360_PMU_ADC_CONFIG, tmp, sizeof(tmp));
+ mad->last_off_timestamps[chan->channel] = ktime_get();
+ /* set prefer channel to 0xf */
+ regmap_update_bits(mad->regmap, MT6360_PMU_ADC_RPT_1,
+ MT6360_PREFERCH_MASK, 0xF << MT6360_PREFERCH_SHFT);
+err_adc_init:
+ mutex_unlock(&mad->adc_lock);
+ return ret;
+}
+
+static const struct iio_info mt6360_adc_iio_info = {
+ .read_raw = mt6360_adc_read_raw,
+};
+
+#define MT6360_ADC_CHAN(_idx, _type) { \
+ .type = _type, \
+ .channel = MT6360_CHAN_##_idx, \
+ .scan_index = MT6360_CHAN_##_idx, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 32, \
+ .storagebits = 32, \
+ .shift = 0, \
+ .endianness = IIO_CPU, \
+ }, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_PROCESSED), \
+ .datasheet_name = #_idx, \
+ .indexed = 1, \
+}
+
+static const struct iio_chan_spec mt6360_adc_channels[] = {
+ MT6360_ADC_CHAN(USBID, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(VBUSDIV5, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(VBUSDIV2, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(VSYS, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(VBAT, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(IBUS, IIO_CURRENT),
+ MT6360_ADC_CHAN(IBAT, IIO_CURRENT),
+ MT6360_ADC_CHAN(CHG_VDDP, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(TEMP_JC, IIO_TEMP),
+ MT6360_ADC_CHAN(VREF_TS, IIO_VOLTAGE),
+ MT6360_ADC_CHAN(TS, IIO_VOLTAGE),
+ IIO_CHAN_SOFT_TIMESTAMP(MT6360_CHAN_MAX),
+};
+
+static irqreturn_t mt6360_pmu_adc_donei_handler(int irq, void *data)
+{
+ struct mt6360_adc_data *mad = iio_priv(data);
+
+ complete(&mad->adc_complete);
+ return IRQ_HANDLED;
+}
+
+static int mt6360_adc_scan_task_threadfn(void *data)
+{
+ struct mt6360_adc_data *mad = data;
+ struct iio_dev *indio_dev = iio_priv_to_dev(mad);
+ int channel_vals[MT6360_CHAN_MAX];
+ int i, bit, var = 0;
+ int ret;
+
+ while (!kthread_should_stop()) {
+ memset(channel_vals, 0, sizeof(channel_vals));
+ i = 0;
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ ret = mt6360_adc_read_raw(indio_dev,
+ mt6360_adc_channels + bit,
+ &var, NULL,
+ IIO_CHAN_INFO_PROCESSED);
+ if (ret < 0)
+ dev_err(mad->dev, "get adc[%d] fail\n", bit);
+ channel_vals[i++] = var;
+ if (kthread_should_stop())
+ goto out;
+ }
+ iio_push_to_buffers_with_timestamp(indio_dev, channel_vals,
+ iio_get_time_ns(indio_dev));
+ }
+out:
+ do_exit(0);
+ return 0;
+}
+
+static int mt6360_adc_iio_post_enable(struct iio_dev *iio_dev)
+{
+ struct mt6360_adc_data *mad = iio_priv(iio_dev);
+
+ mad->scan_task = kthread_run(mt6360_adc_scan_task_threadfn, mad,
+ "scan_thread.%s", dev_name(&iio_dev->dev));
+ return PTR_ERR_OR_ZERO(mad->scan_task);
+}
+
+static int mt6360_adc_iio_pre_disable(struct iio_dev *iio_dev)
+{
+ struct mt6360_adc_data *mad = iio_priv(iio_dev);
+
+ if (mad->scan_task) {
+ kthread_stop(mad->scan_task);
+ mad->scan_task = NULL;
+ }
+ return 0;
+}
+
+static const struct iio_buffer_setup_ops mt6360_adc_iio_setup_ops = {
+ .postenable = mt6360_adc_iio_post_enable,
+ .predisable = mt6360_adc_iio_pre_disable,
+};
+
+static int mt6360_adc_iio_device_register(struct iio_dev *indio_dev)
+{
+ struct mt6360_adc_data *mad = iio_priv(indio_dev);
+ struct iio_buffer *buffer;
+ int ret;
+
+ indio_dev->name = dev_name(mad->dev);
+ indio_dev->dev.parent = mad->dev;
+ indio_dev->dev.of_node = mad->dev->of_node;
+ indio_dev->info = &mt6360_adc_iio_info;
+ indio_dev->channels = mt6360_adc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(mt6360_adc_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+ indio_dev->setup_ops = &mt6360_adc_iio_setup_ops;
+ buffer = devm_iio_kfifo_allocate(mad->dev);
+ if (!buffer)
+ return -ENOMEM;
+ iio_device_attach_buffer(indio_dev, buffer);
+ ret = devm_iio_device_register(mad->dev, indio_dev);
+ if (ret < 0) {
+ dev_err(mad->dev, "Failed to register iio device\n");
+ return ret;
+ }
+ return 0;
+}
+
+static inline int mt6360_adc_reset(struct mt6360_adc_data *info)
+{
+ u8 tmp[3] = {0x80, 0, 0};
+ ktime_t all_off_time;
+ int i;
+
+ all_off_time = ktime_get();
+ for (i = 0; i < MT6360_CHAN_MAX; i++)
+ info->last_off_timestamps[i] = all_off_time;
+ /* enable adc_en, clear adc_chn_en/zcv/en/adc_wait_t/adc_idle_t */
+ return regmap_bulk_write(info->regmap,
+ MT6360_PMU_ADC_CONFIG, tmp, sizeof(tmp));
+}
+
+static int mt6360_adc_probe(struct platform_device *pdev)
+{
+ struct mt6360_adc_data *mad;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*mad));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ mad = iio_priv(indio_dev);
+ mad->dev = &pdev->dev;
+ init_completion(&mad->adc_complete);
+ mutex_init(&mad->adc_lock);
+ platform_set_drvdata(pdev, indio_dev);
+
+ mad->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!mad->regmap) {
+ dev_err(&pdev->dev, "Failed to get parent regmap\n");
+ return -ENODEV;
+ }
+
+ ret = mt6360_adc_reset(mad);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to reset adc\n");
+ return ret;
+ }
+
+ ret = mt6360_adc_iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register iio device\n");
+ return ret;
+ }
+
+ mad->irq = platform_get_irq_byname(pdev, "adc_donei");
+ if (mad->irq < 0) {
+ dev_err(&pdev->dev, "Failed to get adc_done irq\n");
+ return mad->irq;
+ }
+
+ irq_set_status_flags(mad->irq, IRQ_NOAUTOEN);
+ ret = devm_request_threaded_irq(&pdev->dev, mad->irq, NULL,
+ mt6360_pmu_adc_donei_handler,
+ IRQF_TRIGGER_FALLING, "adc_donei",
+ platform_get_drvdata(pdev));
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register adc_done irq\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int mt6360_adc_remove(struct platform_device *pdev)
+{
+ struct mt6360_adc_data *mad = platform_get_drvdata(pdev);
+
+ if (mad->scan_task)
+ kthread_stop(mad->scan_task);
+
+ return 0;
+}
+
+static const struct of_device_id __maybe_unused mt6360_adc_of_id[] = {
+ { .compatible = "mediatek,mt6360_adc", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mt6360_adc_of_id);
+
+static struct platform_driver mt6360_adc_driver = {
+ .driver = {
+ .name = "mt6360_adc",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(mt6360_adc_of_id),
+ },
+ .probe = mt6360_adc_probe,
+ .remove = mt6360_adc_remove,
+};
+module_platform_driver(mt6360_adc_driver);
+
+MODULE_AUTHOR("Gene Chen <gene_chen@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("MT6360 ADC Driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4