Re: [PATCH v3 2/3] iio: Add driver for Broadcom iproc-static-adc
From: Raveendra Padasalagi
Date: Mon Jun 27 2016 - 02:25:44 EST
On Sun, Jun 26, 2016 at 4:08 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> On 22/06/16 07:11, 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>
> A few tiny nitpicks.. Otherwise, looking good to me.
>
> Thanks,
>
> Jonathan
Thank you. I have provided my view on naming "indio_dev->name" below.
Need your opinion/suggestion on the same to address it.
>> ---
>> drivers/iio/adc/Kconfig | 12 +
>> drivers/iio/adc/Makefile | 1 +
>> drivers/iio/adc/bcm_iproc_adc.c | 648 ++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 661 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..e10f6ce
>> --- /dev/null
>> +++ b/drivers/iio/adc/bcm_iproc_adc.c
>> @@ -0,0 +1,648 @@
>> +/*
>> + * 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 iproc_adc_priv *adc_priv;
>> + struct device *dev = &indio_dev->dev;
>> +
>> + adc_priv = iio_priv(indio_dev);
> Trivial, but I'd just do this in one line with the declaration of
> the local variable.
>
> struct iprov_adc_priv *adc_priv = iio_priv(indio_dev);
Yes, I missed it to fix. Will address in the next patch.
Thanks.
>
>> +
>> + 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 = dev_name(&pdev->dev);
> This name should reflect the part name rather than anything else.
> Here this is easy as there is only one part name. I'd just put
> it in directly here.
I thought putting in the part name directly here would hard code and
looked at the other ADC IIO drivers and found to be using the dev_name()
call.
"adc: adc@180a6000" this is the current node name used for adc in .dts file
so it will take adc@180a6000 as the name and export it to sysfs.
If I have to put the name directly then it should look like "adc" ??
or "iproc-static-adc" ?
then there wouldn't be a direct reference to the device name in .dts file.
So I think it's better to keep the name captured from the call
dev_name(&pdev->dev);
Please suggest whether to put the name directly or keep the existing method.
>> + 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),
>> + },
>> +};
> 1 blank line is always enough. Here actually, no blank lines is
> the convention given the connection between the next line and the
> structure.
Yes, will fix it in the next patch.
>> +
>> +
>> +module_platform_driver(iproc_adc_driver);
>> +
>> +MODULE_DESCRIPTION("IPROC ADC driver");
>> +MODULE_AUTHOR("Broadcom");
> Module author should be an individual ideally (it's an email address
> to pester!) Given you are signing off, you are the obvious choice.
> If several people were involved, you can have multiple MODULE_AUTHOR
> entries. One person for each one though.
Yes, will fix it in the next patch.
>> +MODULE_LICENSE("GPL v2");
>>
>