Re: [PATCH v4 2/3] iio: Add driver for Broadcom iproc-static-adc
From: Jonathan Cameron
Date: Sun Jul 03 2016 - 06:33:50 EST
On 28/06/16 08:40, Raveendra Padasalagi wrote:
> This patch adds basic driver implementation for Broadcom's
> static adc controller used in iProc SoC's family.
>
> Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@xxxxxxxxxxxx>
> Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
> Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx>
Looks good to me.
Applied to the togreg branch of iio.git -- initially pushed out as
testing for the autobuilders to play with it.
Thanks,
Jonathan
> ---
> drivers/iio/adc/Kconfig | 12 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/bcm_iproc_adc.c | 644 ++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 657 insertions(+)
> create mode 100644 drivers/iio/adc/bcm_iproc_adc.c
>
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 25378c5..1de31bd 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -153,6 +153,18 @@ config AXP288_ADC
> To compile this driver as a module, choose M here: the module will be
> called axp288_adc.
>
> +config BCM_IPROC_ADC
> + tristate "Broadcom IPROC ADC driver"
> + depends on ARCH_BCM_IPROC || COMPILE_TEST
> + depends on MFD_SYSCON
> + default ARCH_BCM_CYGNUS
> + help
> + Say Y here if you want to add support for the Broadcom static
> + ADC driver.
> +
> + Broadcom iProc ADC driver. Broadcom iProc ADC controller has 8
> + channels. The driver allows the user to read voltage values.
> +
> config BERLIN2_ADC
> tristate "Marvell Berlin2 ADC driver"
> depends on ARCH_BERLIN
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 38638d4..0ba0d50 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -16,6 +16,7 @@ obj-$(CONFIG_AD799X) += ad799x.o
> obj-$(CONFIG_AT91_ADC) += at91_adc.o
> obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o
> obj-$(CONFIG_AXP288_ADC) += axp288_adc.o
> +obj-$(CONFIG_BCM_IPROC_ADC) += bcm_iproc_adc.o
> obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
> obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
> obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
> diff --git a/drivers/iio/adc/bcm_iproc_adc.c b/drivers/iio/adc/bcm_iproc_adc.c
> new file mode 100644
> index 0000000..21d38c8
> --- /dev/null
> +++ b/drivers/iio/adc/bcm_iproc_adc.c
> @@ -0,0 +1,644 @@
> +/*
> + * Copyright 2016 Broadcom
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License, version 2, as
> + * published by the Free Software Foundation (the "GPL").
> + *
> + * 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 version 2 (GPLv2) for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * version 2 (GPLv2) along with this source code.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/io.h>
> +#include <linux/clk.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/iio/iio.h>
> +
> +/* Below Register's are common to IPROC ADC and Touchscreen IP */
> +#define IPROC_REGCTL1 0x00
> +#define IPROC_REGCTL2 0x04
> +#define IPROC_INTERRUPT_THRES 0x08
> +#define IPROC_INTERRUPT_MASK 0x0c
> +#define IPROC_INTERRUPT_STATUS 0x10
> +#define IPROC_ANALOG_CONTROL 0x1c
> +#define IPROC_CONTROLLER_STATUS 0x14
> +#define IPROC_AUX_DATA 0x20
> +#define IPROC_SOFT_BYPASS_CONTROL 0x38
> +#define IPROC_SOFT_BYPASS_DATA 0x3C
> +
> +/* IPROC ADC Channel register offsets */
> +#define IPROC_ADC_CHANNEL_REGCTL1 0x800
> +#define IPROC_ADC_CHANNEL_REGCTL2 0x804
> +#define IPROC_ADC_CHANNEL_STATUS 0x808
> +#define IPROC_ADC_CHANNEL_INTERRUPT_STATUS 0x80c
> +#define IPROC_ADC_CHANNEL_INTERRUPT_MASK 0x810
> +#define IPROC_ADC_CHANNEL_DATA 0x814
> +#define IPROC_ADC_CHANNEL_OFFSET 0x20
> +
> +/* Bit definitions for IPROC_REGCTL2 */
> +#define IPROC_ADC_AUXIN_SCAN_ENA BIT(0)
> +#define IPROC_ADC_PWR_LDO BIT(5)
> +#define IPROC_ADC_PWR_ADC BIT(4)
> +#define IPROC_ADC_PWR_BG BIT(3)
> +#define IPROC_ADC_CONTROLLER_EN BIT(17)
> +
> +/* Bit definitions for IPROC_INTERRUPT_MASK and IPROC_INTERRUPT_STATUS */
> +#define IPROC_ADC_AUXDATA_RDY_INTR BIT(3)
> +#define IPROC_ADC_INTR 9
> +#define IPROC_ADC_INTR_MASK (0xFF << IPROC_ADC_INTR)
> +
> +/* Bit definitions for IPROC_ANALOG_CONTROL */
> +#define IPROC_ADC_CHANNEL_SEL 11
> +#define IPROC_ADC_CHANNEL_SEL_MASK (0x7 << IPROC_ADC_CHANNEL_SEL)
> +
> +/* Bit definitions for IPROC_ADC_CHANNEL_REGCTL1 */
> +#define IPROC_ADC_CHANNEL_ROUNDS 0x2
> +#define IPROC_ADC_CHANNEL_ROUNDS_MASK (0x3F << IPROC_ADC_CHANNEL_ROUNDS)
> +#define IPROC_ADC_CHANNEL_MODE 0x1
> +#define IPROC_ADC_CHANNEL_MODE_MASK (0x1 << IPROC_ADC_CHANNEL_MODE)
> +#define IPROC_ADC_CHANNEL_MODE_TDM 0x1
> +#define IPROC_ADC_CHANNEL_MODE_SNAPSHOT 0x0
> +#define IPROC_ADC_CHANNEL_ENABLE 0x0
> +#define IPROC_ADC_CHANNEL_ENABLE_MASK 0x1
> +
> +/* Bit definitions for IPROC_ADC_CHANNEL_REGCTL2 */
> +#define IPROC_ADC_CHANNEL_WATERMARK 0x0
> +#define IPROC_ADC_CHANNEL_WATERMARK_MASK \
> + (0x3F << IPROC_ADC_CHANNEL_WATERMARK)
> +
> +#define IPROC_ADC_WATER_MARK_LEVEL 0x1
> +
> +/* Bit definitions for IPROC_ADC_CHANNEL_STATUS */
> +#define IPROC_ADC_CHANNEL_DATA_LOST 0x0
> +#define IPROC_ADC_CHANNEL_DATA_LOST_MASK \
> + (0x0 << IPROC_ADC_CHANNEL_DATA_LOST)
> +#define IPROC_ADC_CHANNEL_VALID_ENTERIES 0x1
> +#define IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK \
> + (0xFF << IPROC_ADC_CHANNEL_VALID_ENTERIES)
> +#define IPROC_ADC_CHANNEL_TOTAL_ENTERIES 0x9
> +#define IPROC_ADC_CHANNEL_TOTAL_ENTERIES_MASK \
> + (0xFF << IPROC_ADC_CHANNEL_TOTAL_ENTERIES)
> +
> +/* Bit definitions for IPROC_ADC_CHANNEL_INTERRUPT_MASK */
> +#define IPROC_ADC_CHANNEL_WTRMRK_INTR 0x0
> +#define IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK \
> + (0x1 << IPROC_ADC_CHANNEL_WTRMRK_INTR)
> +#define IPROC_ADC_CHANNEL_FULL_INTR 0x1
> +#define IPROC_ADC_CHANNEL_FULL_INTR_MASK \
> + (0x1 << IPROC_ADC_IPROC_ADC_CHANNEL_FULL_INTR)
> +#define IPROC_ADC_CHANNEL_EMPTY_INTR 0x2
> +#define IPROC_ADC_CHANNEL_EMPTY_INTR_MASK \
> + (0x1 << IPROC_ADC_CHANNEL_EMPTY_INTR)
> +
> +#define IPROC_ADC_WATER_MARK_INTR_ENABLE 0x1
> +
> +/* Number of time to retry a set of the interrupt mask reg */
> +#define IPROC_ADC_INTMASK_RETRY_ATTEMPTS 10
> +
> +#define IPROC_ADC_READ_TIMEOUT (HZ*2)
> +
> +#define iproc_adc_dbg_reg(dev, priv, reg) \
> +do { \
> + u32 val; \
> + regmap_read(priv->regmap, reg, &val); \
> + dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \
> +} while (0)
> +
> +struct iproc_adc_priv {
> + struct regmap *regmap;
> + struct clk *adc_clk;
> + struct mutex mutex;
> + int irqno;
> + int chan_val;
> + int chan_id;
> + struct completion completion;
> +};
> +
> +static void iproc_adc_reg_dump(struct iio_dev *indio_dev)
> +{
> + struct device *dev = &indio_dev->dev;
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> +
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL1);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL2);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_THRES);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_MASK);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_STATUS);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_CONTROLLER_STATUS);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_ANALOG_CONTROL);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_AUX_DATA);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_CONTROL);
> + iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_DATA);
> +}
> +
> +static irqreturn_t iproc_adc_interrupt_handler(int irq, void *data)
> +{
> + u32 channel_intr_status;
> + u32 intr_status;
> + u32 intr_mask;
> + struct iio_dev *indio_dev = data;
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> +
> + /*
> + * This interrupt is shared with the touchscreen driver.
> + * Make sure this interrupt is intended for us.
> + * Handle only ADC channel specific interrupts.
> + */
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &intr_mask);
> + intr_status = intr_status & intr_mask;
> + channel_intr_status = (intr_status & IPROC_ADC_INTR_MASK) >>
> + IPROC_ADC_INTR;
> + if (channel_intr_status)
> + return IRQ_WAKE_THREAD;
> +
> + return IRQ_NONE;
> +}
> +
> +static irqreturn_t iproc_adc_interrupt_thread(int irq, void *data)
> +{
> + irqreturn_t retval = IRQ_NONE;
> + struct iproc_adc_priv *adc_priv;
> + struct iio_dev *indio_dev = data;
> + unsigned int valid_entries;
> + u32 intr_status;
> + u32 intr_channels;
> + u32 channel_status;
> + u32 ch_intr_status;
> +
> + adc_priv = iio_priv(indio_dev);
> +
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
> + dev_dbg(&indio_dev->dev, "iproc_adc_interrupt_thread(),INTRPT_STS:%x\n",
> + intr_status);
> +
> + intr_channels = (intr_status & IPROC_ADC_INTR_MASK) >> IPROC_ADC_INTR;
> + if (intr_channels) {
> + regmap_read(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
> + IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
> + &ch_intr_status);
> +
> + if (ch_intr_status & IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK) {
> + regmap_read(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_STATUS +
> + IPROC_ADC_CHANNEL_OFFSET *
> + adc_priv->chan_id,
> + &channel_status);
> +
> + valid_entries = ((channel_status &
> + IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK) >>
> + IPROC_ADC_CHANNEL_VALID_ENTERIES);
> + if (valid_entries >= 1) {
> + regmap_read(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_DATA +
> + IPROC_ADC_CHANNEL_OFFSET *
> + adc_priv->chan_id,
> + &adc_priv->chan_val);
> + complete(&adc_priv->completion);
> + } else {
> + dev_err(&indio_dev->dev,
> + "No data rcvd on channel %d\n",
> + adc_priv->chan_id);
> + }
> + regmap_write(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_INTERRUPT_MASK +
> + IPROC_ADC_CHANNEL_OFFSET *
> + adc_priv->chan_id,
> + (ch_intr_status &
> + ~(IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK)));
> + }
> + regmap_write(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
> + IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
> + ch_intr_status);
> + regmap_write(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
> + intr_channels);
> + retval = IRQ_HANDLED;
> + }
> +
> + return retval;
> +}
> +
> +static int iproc_adc_do_read(struct iio_dev *indio_dev,
> + int channel,
> + u16 *p_adc_data)
> +{
> + int read_len = 0;
> + u32 val;
> + u32 mask;
> + u32 val_check;
> + int failed_cnt = 0;
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> +
> + mutex_lock(&adc_priv->mutex);
> +
> + /*
> + * After a read is complete the ADC interrupts will be disabled so
> + * we can assume this section of code is safe from interrupts.
> + */
> + adc_priv->chan_val = -1;
> + adc_priv->chan_id = channel;
> +
> + reinit_completion(&adc_priv->completion);
> + /* Clear any pending interrupt */
> + regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
> + IPROC_ADC_INTR_MASK | IPROC_ADC_AUXDATA_RDY_INTR,
> + ((0x0 << channel) << IPROC_ADC_INTR) |
> + IPROC_ADC_AUXDATA_RDY_INTR);
> +
> + /* Configure channel for snapshot mode and enable */
> + val = (BIT(IPROC_ADC_CHANNEL_ROUNDS) |
> + (IPROC_ADC_CHANNEL_MODE_SNAPSHOT << IPROC_ADC_CHANNEL_MODE) |
> + (0x1 << IPROC_ADC_CHANNEL_ENABLE));
> +
> + mask = IPROC_ADC_CHANNEL_ROUNDS_MASK | IPROC_ADC_CHANNEL_MODE_MASK |
> + IPROC_ADC_CHANNEL_ENABLE_MASK;
> + regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL1 +
> + IPROC_ADC_CHANNEL_OFFSET * channel),
> + mask, val);
> +
> + /* Set the Watermark for a channel */
> + regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL2 +
> + IPROC_ADC_CHANNEL_OFFSET * channel),
> + IPROC_ADC_CHANNEL_WATERMARK_MASK,
> + 0x1);
> +
> + /* Enable water mark interrupt */
> + regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_INTERRUPT_MASK +
> + IPROC_ADC_CHANNEL_OFFSET *
> + channel),
> + IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK,
> + IPROC_ADC_WATER_MARK_INTR_ENABLE);
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val);
> +
> + /* Enable ADC interrupt for a channel */
> + val |= (BIT(channel) << IPROC_ADC_INTR);
> + regmap_write(adc_priv->regmap, IPROC_INTERRUPT_MASK, val);
> +
> + /*
> + * There seems to be a very rare issue where writing to this register
> + * does not take effect. To work around the issue we will try multiple
> + * writes. In total we will spend about 10*10 = 100 us attempting this.
> + * Testing has shown that this may loop a few time, but we have never
> + * hit the full count.
> + */
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
> + while (val_check != val) {
> + failed_cnt++;
> +
> + if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS)
> + break;
> +
> + udelay(10);
> + regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
> + IPROC_ADC_INTR_MASK,
> + ((0x1 << channel) <<
> + IPROC_ADC_INTR));
> +
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
> + }
> +
> + if (failed_cnt) {
> + dev_dbg(&indio_dev->dev,
> + "IntMask failed (%d times)", failed_cnt);
> + if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS) {
> + dev_err(&indio_dev->dev,
> + "IntMask set failed. Read will likely fail.");
> + read_len = -EIO;
> + goto adc_err;
> + };
> + }
> + regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
> +
> + if (wait_for_completion_timeout(&adc_priv->completion,
> + IPROC_ADC_READ_TIMEOUT) > 0) {
> +
> + /* Only the lower 16 bits are relevant */
> + *p_adc_data = adc_priv->chan_val & 0xFFFF;
> + read_len = sizeof(*p_adc_data);
> +
> + } else {
> + /*
> + * We never got the interrupt, something went wrong.
> + * Perhaps the interrupt may still be coming, we do not want
> + * that now. Lets disable the ADC interrupt, and clear the
> + * status to put it back in to normal state.
> + */
> + read_len = -ETIMEDOUT;
> + goto adc_err;
> + }
> + mutex_unlock(&adc_priv->mutex);
> +
> + return read_len;
> +
> +adc_err:
> + regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
> + IPROC_ADC_INTR_MASK,
> + ((0x0 << channel) << IPROC_ADC_INTR));
> +
> + regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
> + IPROC_ADC_INTR_MASK,
> + ((0x0 << channel) << IPROC_ADC_INTR));
> +
> + dev_err(&indio_dev->dev, "Timed out waiting for ADC data!\n");
> + iproc_adc_reg_dump(indio_dev);
> + mutex_unlock(&adc_priv->mutex);
> +
> + return read_len;
> +}
> +
> +static int iproc_adc_enable(struct iio_dev *indio_dev)
> +{
> + u32 val;
> + u32 channel_id;
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> + int ret;
> +
> + /* Set i_amux = 3b'000, select channel 0 */
> + ret = regmap_update_bits(adc_priv->regmap, IPROC_ANALOG_CONTROL,
> + IPROC_ADC_CHANNEL_SEL_MASK, 0);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write IPROC_ANALOG_CONTROL %d\n", ret);
> + return ret;
> + }
> + adc_priv->chan_val = -1;
> +
> + /*
> + * PWR up LDO, ADC, and Band Gap (0 to enable)
> + * Also enable ADC controller (set high)
> + */
> + ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to read IPROC_REGCTL2 %d\n", ret);
> + return ret;
> + }
> +
> + val &= ~(IPROC_ADC_PWR_LDO | IPROC_ADC_PWR_ADC | IPROC_ADC_PWR_BG);
> +
> + ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write IPROC_REGCTL2 %d\n", ret);
> + return ret;
> + }
> +
> + ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to read IPROC_REGCTL2 %d\n", ret);
> + return ret;
> + }
> +
> + val |= IPROC_ADC_CONTROLLER_EN;
> + ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write IPROC_REGCTL2 %d\n", ret);
> + return ret;
> + }
> +
> + for (channel_id = 0; channel_id < indio_dev->num_channels;
> + channel_id++) {
> + ret = regmap_write(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_INTERRUPT_MASK +
> + IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write ADC_CHANNEL_INTERRUPT_MASK %d\n",
> + ret);
> + return ret;
> + }
> +
> + ret = regmap_write(adc_priv->regmap,
> + IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
> + IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write ADC_CHANNEL_INTERRUPT_STATUS %d\n",
> + ret);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void iproc_adc_disable(struct iio_dev *indio_dev)
> +{
> + u32 val;
> + int ret;
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> +
> + ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to read IPROC_REGCTL2 %d\n", ret);
> + return;
> + }
> +
> + val &= ~IPROC_ADC_CONTROLLER_EN;
> + ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
> + if (ret) {
> + dev_err(&indio_dev->dev,
> + "failed to write IPROC_REGCTL2 %d\n", ret);
> + return;
> + }
> +}
> +
> +static int iproc_adc_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val,
> + int *val2,
> + long mask)
> +{
> + u16 adc_data;
> + int err;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + err = iproc_adc_do_read(indio_dev, chan->channel, &adc_data);
> + if (err < 0)
> + return err;
> + *val = adc_data;
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
> + case IIO_VOLTAGE:
> + *val = 1800;
> + *val2 = 10;
> + return IIO_VAL_FRACTIONAL_LOG2;
> + default:
> + return -EINVAL;
> + }
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static const struct iio_info iproc_adc_iio_info = {
> + .read_raw = &iproc_adc_read_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +#define IPROC_ADC_CHANNEL(_index, _id) { \
> + .type = IIO_VOLTAGE, \
> + .indexed = 1, \
> + .channel = _index, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> + .datasheet_name = _id, \
> +}
> +
> +static const struct iio_chan_spec iproc_adc_iio_channels[] = {
> + IPROC_ADC_CHANNEL(0, "adc0"),
> + IPROC_ADC_CHANNEL(1, "adc1"),
> + IPROC_ADC_CHANNEL(2, "adc2"),
> + IPROC_ADC_CHANNEL(3, "adc3"),
> + IPROC_ADC_CHANNEL(4, "adc4"),
> + IPROC_ADC_CHANNEL(5, "adc5"),
> + IPROC_ADC_CHANNEL(6, "adc6"),
> + IPROC_ADC_CHANNEL(7, "adc7"),
> +};
> +
> +static int iproc_adc_probe(struct platform_device *pdev)
> +{
> + struct iproc_adc_priv *adc_priv;
> + struct iio_dev *indio_dev = NULL;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&pdev->dev,
> + sizeof(*adc_priv));
> + if (!indio_dev) {
> + dev_err(&pdev->dev, "failed to allocate iio device\n");
> + return -ENOMEM;
> + }
> +
> + adc_priv = iio_priv(indio_dev);
> + platform_set_drvdata(pdev, indio_dev);
> +
> + mutex_init(&adc_priv->mutex);
> +
> + init_completion(&adc_priv->completion);
> +
> + adc_priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
> + "adc-syscon");
> + if (IS_ERR(adc_priv->regmap)) {
> + dev_err(&pdev->dev, "failed to get handle for tsc syscon\n");
> + ret = PTR_ERR(adc_priv->regmap);
> + return ret;
> + }
> +
> + adc_priv->adc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
> + if (IS_ERR(adc_priv->adc_clk)) {
> + dev_err(&pdev->dev,
> + "failed getting clock tsc_clk\n");
> + ret = PTR_ERR(adc_priv->adc_clk);
> + return ret;
> + }
> +
> + adc_priv->irqno = platform_get_irq(pdev, 0);
> + if (adc_priv->irqno <= 0) {
> + dev_err(&pdev->dev, "platform_get_irq failed\n");
> + ret = -ENODEV;
> + return ret;
> + }
> +
> + ret = regmap_update_bits(adc_priv->regmap, IPROC_REGCTL2,
> + IPROC_ADC_AUXIN_SCAN_ENA, 0);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to write IPROC_REGCTL2 %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_request_threaded_irq(&pdev->dev, adc_priv->irqno,
> + iproc_adc_interrupt_thread,
> + iproc_adc_interrupt_handler,
> + IRQF_SHARED, "iproc-adc", indio_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "request_irq error %d\n", ret);
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(adc_priv->adc_clk);
> + if (ret) {
> + dev_err(&pdev->dev,
> + "clk_prepare_enable failed %d\n", ret);
> + return ret;
> + }
> +
> + ret = iproc_adc_enable(indio_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to enable adc %d\n", ret);
> + goto err_adc_enable;
> + }
> +
> + indio_dev->name = "iproc-static-adc";
> + indio_dev->dev.parent = &pdev->dev;
> + indio_dev->dev.of_node = pdev->dev.of_node;
> + indio_dev->info = &iproc_adc_iio_info;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->channels = iproc_adc_iio_channels;
> + indio_dev->num_channels = ARRAY_SIZE(iproc_adc_iio_channels);
> +
> + ret = iio_device_register(indio_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "iio_device_register failed:err %d\n", ret);
> + goto err_clk;
> + }
> +
> + return 0;
> +
> +err_clk:
> + iproc_adc_disable(indio_dev);
> +err_adc_enable:
> + clk_disable_unprepare(adc_priv->adc_clk);
> +
> + return ret;
> +}
> +
> +static int iproc_adc_remove(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> + struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> + iproc_adc_disable(indio_dev);
> + clk_disable_unprepare(adc_priv->adc_clk);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id iproc_adc_of_match[] = {
> + {.compatible = "brcm,iproc-static-adc", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, iproc_adc_of_match);
> +
> +static struct platform_driver iproc_adc_driver = {
> + .probe = iproc_adc_probe,
> + .remove = iproc_adc_remove,
> + .driver = {
> + .name = "iproc-static-adc",
> + .of_match_table = of_match_ptr(iproc_adc_of_match),
> + },
> +};
> +module_platform_driver(iproc_adc_driver);
> +
> +MODULE_DESCRIPTION("Broadcom iProc ADC controller driver");
> +MODULE_AUTHOR("Raveendra Padasalagi <raveendra.padasalagi@xxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL v2");
>