[PATCH] adc: add adc driver for Hisilicon BVT SOCs
From: Allen Liu
Date: Sat Jan 07 2017 - 05:25:11 EST
Add ADC driver for the ADC controller found on HiSilicon BVT SOCs, like Hi3516CV300, etc.
The ADC controller is primarily in charge of detecting voltage.
Reviewed-by: Kevin Li <kevin.lixu@xxxxxxxxxxxxx>
Signed-off-by: Allen Liu <liurenzhong@xxxxxxxxxxxxx>
---
.../devicetree/bindings/iio/adc/hibvt-lsadc.txt | 23 ++
drivers/iio/adc/Kconfig | 10 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/hibvt_lsadc.c | 335 +++++++++++++++++++++
4 files changed, 369 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
create mode 100644 drivers/iio/adc/hibvt_lsadc.c
diff --git a/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt b/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
new file mode 100644
index 0000000..fce1ff4
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
@@ -0,0 +1,23 @@
+Hisilicon BVT Low Speed (LS) A/D Converter bindings
+
+Required properties:
+- compatible: should be "hisilicon,<name>-lsadc"
+ - "hisilicon,hi3516cv300-lsadc": for hi3516cv300
+
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- interrupts: The interrupt number for the ADC device.
+
+Optional properties:
+- resets: Must contain an entry for each entry in reset-names if need support
+ this option. See ../../reset/reset.txt for details.
+- reset-names: Must include the name "lsadc-crg".
+
+Example:
+ adc: adc@120e0000 {
+ compatible = "hisilicon,hi3516cv300-lsadc";
+ reg = <0x120e0000 0x1000>;
+ interrupts = <19>;
+ resets = <&crg 0x7c 3>;
+ reset-names = "lsadc-crg";
+ };
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 99c0514..0443f51 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -225,6 +225,16 @@ config HI8435
This driver can also be built as a module. If so, the module will be
called hi8435.
+config HIBVT_LSADC
+ tristate "HIBVT LSADC driver"
+ depends on ARCH_HISI || COMPILE_TEST
+ help
+ Say yes here to build support for the LSADC found in SoCs from
+ hisilicon BVT chip.
+
+ To compile this driver as a module, choose M here: the
+ module will be called hibvt_lsadc.
+
config INA2XX_ADC
tristate "Texas Instruments INA2xx Power Monitors IIO driver"
depends on I2C && !SENSORS_INA2XX
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 7a40c04..6554d92 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
obj-$(CONFIG_HI8435) += hi8435.o
+obj-$(CONFIG_HIBVT_LSADC) += hibvt_lsadc.o
obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
diff --git a/drivers/iio/adc/hibvt_lsadc.c b/drivers/iio/adc/hibvt_lsadc.c
new file mode 100644
index 0000000..aaf2024
--- /dev/null
+++ b/drivers/iio/adc/hibvt_lsadc.c
@@ -0,0 +1,335 @@
+/*
+ * Hisilicon BVT Low Speed (LS) A/D Converter
+ * Copyright (C) 2016 HiSilicon Technologies Co., Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/reset.h>
+#include <linux/regulator/consumer.h>
+#include <linux/iio/iio.h>
+
+/* hisilicon bvt adc registers definitions */
+#define HIBVT_LSADC_CONFIG 0x00
+#define HIBVT_CONFIG_DEGLITCH BIT(17)
+#define HIBVT_CONFIG_RESET BIT(15)
+#define HIBVT_CONFIG_POWERDOWN BIT(14)
+#define HIBVT_CONFIG_MODE BIT(13)
+#define HIBVT_CONFIG_CHNC BIT(10)
+#define HIBVT_CONFIG_CHNB BIT(9)
+#define HIBVT_CONFIG_CHNA BIT(8)
+
+#define HIBVT_LSADC_TIMESCAN 0x08
+#define HIBVT_LSADC_INTEN 0x10
+#define HIBVT_LSADC_INTSTATUS 0x14
+#define HIBVT_LSADC_INTCLR 0x18
+#define HIBVT_LSADC_START 0x1C
+#define HIBVT_LSADC_STOP 0x20
+#define HIBVT_LSADC_ACTBIT 0x24
+#define HIBVT_LSADC_CHNDATA 0x2C
+
+#define HIBVT_LSADC_CON_EN (1u << 0)
+#define HIBVT_LSADC_CON_DEN (0u << 0)
+
+#define HIBVT_LSADC_NUM_BITS_V1 10
+#define HIBVT_LSADC_CHN_MASK_v1 0x7
+
+/* fix clk:3000000, default tscan set 10ms */
+#define HIBVT_LSADC_TSCAN_MS (10*3000)
+
+#define HIBVT_LSADC_TIMEOUT msecs_to_jiffies(100)
+
+/* default voltage scale for every channel <mv> */
+static int g_hibvt_lsadc_voltage[] = {
+ 3300, 3300, 3300
+};
+
+struct hibvt_lsadc {
+ void __iomem *regs;
+ struct completion completion;
+ struct reset_control *reset;
+ const struct hibvt_lsadc_data *data;
+ unsigned int cur_chn;
+ unsigned int value;
+};
+
+struct hibvt_lsadc_data {
+ int num_bits;
+ const struct iio_chan_spec *channels;
+ int num_channels;
+
+ void (*clear_irq)(struct hibvt_lsadc *info, int mask);
+ void (*start_conv)(struct hibvt_lsadc *info);
+ void (*stop_conv)(struct hibvt_lsadc *info);
+};
+
+static int hibvt_lsadc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct hibvt_lsadc *info = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+
+ reinit_completion(&info->completion);
+
+ /* Select the channel to be used */
+ info->cur_chn = chan->channel;
+
+ if (info->data->start_conv)
+ info->data->start_conv(info);
+
+ if (!wait_for_completion_timeout(&info->completion,
+ HIBVT_LSADC_TIMEOUT)) {
+ if (info->data->stop_conv)
+ info->data->stop_conv(info);
+ mutex_unlock(&indio_dev->mlock);
+ return -ETIMEDOUT;
+ }
+
+ *val = info->value;
+ mutex_unlock(&indio_dev->mlock);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = g_hibvt_lsadc_voltage[chan->channel];
+ *val2 = info->data->num_bits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
+ }
+}
+
+static irqreturn_t hibvt_lsadc_isr(int irq, void *dev_id)
+{
+ struct hibvt_lsadc *info = (struct hibvt_lsadc *)dev_id;
+ int mask;
+
+ mask = readl(info->regs + HIBVT_LSADC_INTSTATUS);
+ if ((mask & HIBVT_LSADC_CHN_MASK_v1) == 0)
+ return IRQ_NONE;
+
+ /* Clear irq */
+ mask &= HIBVT_LSADC_CHN_MASK_v1;
+ if (info->data->clear_irq)
+ info->data->clear_irq(info, mask);
+
+ /* Read value */
+ info->value = readl(info->regs +
+ HIBVT_LSADC_CHNDATA + (info->cur_chn << 2));
+ info->value &= GENMASK(info->data->num_bits - 1, 0);
+
+ /* stop adc */
+ if (info->data->stop_conv)
+ info->data->stop_conv(info);
+
+ complete(&info->completion);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_info hibvt_lsadc_iio_info = {
+ .read_raw = hibvt_lsadc_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define HIBVT_LSADC_CHANNEL(_index, _id) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _index, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .datasheet_name = _id, \
+}
+
+static const struct iio_chan_spec hibvt_lsadc_iio_channels[] = {
+ HIBVT_LSADC_CHANNEL(0, "adc0"),
+ HIBVT_LSADC_CHANNEL(1, "adc1"),
+ HIBVT_LSADC_CHANNEL(2, "adc2"),
+};
+
+static void hibvt_lsadc_v1_clear_irq(struct hibvt_lsadc *info, int mask)
+{
+ writel(mask, info->regs + HIBVT_LSADC_INTCLR);
+}
+
+static void hibvt_lsadc_v1_start_conv(struct hibvt_lsadc *info)
+{
+ unsigned int con;
+
+ /* set number bit */
+ con = GENMASK(info->data->num_bits - 1, 0);
+ writel(con, (info->regs + HIBVT_LSADC_ACTBIT));
+
+ /* config */
+ con = readl(info->regs + HIBVT_LSADC_CONFIG);
+ con &= ~HIBVT_CONFIG_RESET;
+ con |= (HIBVT_CONFIG_POWERDOWN | HIBVT_CONFIG_DEGLITCH |
+ HIBVT_CONFIG_MODE);
+ con &= ~(HIBVT_CONFIG_CHNA | HIBVT_CONFIG_CHNB | HIBVT_CONFIG_CHNC);
+ con |= (HIBVT_CONFIG_CHNA << info->cur_chn);
+ writel(con, (info->regs + HIBVT_LSADC_CONFIG));
+
+ /* set timescan */
+ writel(HIBVT_LSADC_TSCAN_MS, (info->regs + HIBVT_LSADC_TIMESCAN));
+
+ /* clear interrupt */
+ writel(HIBVT_LSADC_CHN_MASK_v1, info->regs + HIBVT_LSADC_INTCLR);
+
+ /* enable interrupt */
+ writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_INTEN));
+
+ /* start scan */
+ writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_START));
+}
+
+static void hibvt_lsadc_v1_stop_conv(struct hibvt_lsadc *info)
+{
+ /* reset the timescan */
+ writel(HIBVT_LSADC_CON_DEN, (info->regs + HIBVT_LSADC_TIMESCAN));
+
+ /* disable interrupt */
+ writel(HIBVT_LSADC_CON_DEN, (info->regs + HIBVT_LSADC_INTEN));
+
+ /* stop scan */
+ writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_STOP));
+}
+
+static const struct hibvt_lsadc_data lsadc_data_v1 = {
+ .num_bits = HIBVT_LSADC_NUM_BITS_V1,
+ .channels = hibvt_lsadc_iio_channels,
+ .num_channels = ARRAY_SIZE(hibvt_lsadc_iio_channels),
+
+ .clear_irq = hibvt_lsadc_v1_clear_irq,
+ .start_conv = hibvt_lsadc_v1_start_conv,
+ .stop_conv = hibvt_lsadc_v1_stop_conv,
+};
+
+static const struct of_device_id hibvt_lsadc_match[] = {
+ {
+ .compatible = "hisilicon,hi3516cv300-lsadc",
+ .data = &lsadc_data_v1,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, hibvt_lsadc_match);
+
+/* Reset LSADC Controller */
+static void hibvt_lsadc_reset_controller(struct reset_control *reset)
+{
+ reset_control_assert(reset);
+ usleep_range(10, 20);
+ reset_control_deassert(reset);
+}
+
+static int hibvt_lsadc_probe(struct platform_device *pdev)
+{
+ struct hibvt_lsadc *info = NULL;
+ struct device_node *np = pdev->dev.of_node;
+ struct iio_dev *indio_dev = NULL;
+ struct resource *mem;
+ const struct of_device_id *match;
+ int ret;
+ int irq;
+
+ if (!np)
+ return -ENODEV;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
+ if (!indio_dev) {
+ dev_err(&pdev->dev, "failed allocating iio device\n");
+ return -ENOMEM;
+ }
+ info = iio_priv(indio_dev);
+
+ match = of_match_device(hibvt_lsadc_match, &pdev->dev);
+ info->data = match->data;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ info->regs = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(info->regs))
+ return PTR_ERR(info->regs);
+
+ /*
+ * The reset should be an optional property, as it should work
+ * with old devicetrees as well
+ */
+ info->reset = devm_reset_control_get(&pdev->dev, "lsadc-crg");
+ if (IS_ERR(info->reset)) {
+ ret = PTR_ERR(info->reset);
+ if (ret != -ENOENT)
+ return ret;
+
+ dev_dbg(&pdev->dev, "no reset control found\n");
+ info->reset = NULL;
+ }
+
+ init_completion(&info->completion);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq, hibvt_lsadc_isr,
+ 0, dev_name(&pdev->dev), info);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed requesting irq %d\n", irq);
+ return ret;
+ }
+
+ if (info->reset)
+ hibvt_lsadc_reset_controller(info->reset);
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ indio_dev->name = dev_name(&pdev->dev);
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->dev.of_node = pdev->dev.of_node;
+ indio_dev->info = &hibvt_lsadc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ indio_dev->channels = info->data->channels;
+ indio_dev->num_channels = info->data->num_channels;
+
+ ret = devm_iio_device_register(&pdev->dev, indio_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed register iio device\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver hibvt_lsadc_driver = {
+ .probe = hibvt_lsadc_probe,
+ .driver = {
+ .name = "hibvt-lsadc",
+ .of_match_table = hibvt_lsadc_match,
+ },
+};
+
+module_platform_driver(hibvt_lsadc_driver);
+
+MODULE_AUTHOR("Allen Liu <liurenzhong@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("hisilicon BVT LSADC driver");
+MODULE_LICENSE("GPL v2");
--
2.1.4