[PATCH v3 2/3] iio: Add driver for Broadcom iproc-static-adc
Raveendra Padasalagi
raveendra.padasalagi at broadcom.com
Sun Jun 26 23:25:38 PDT 2016
On Sun, Jun 26, 2016 at 4:08 PM, Jonathan Cameron <jic23 at kernel.org> 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 at broadcom.com>
>> Reviewed-by: Ray Jui <ray.jui at broadcom.com>
>> Reviewed-by: Scott Branden <scott.branden at broadcom.com>
> 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 at 180a6000" this is the current node name used for adc in .dts file
so it will take adc at 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");
>>
>
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