Re: [PATCH v3 2/3] iio: adc: Add Xilinx AMS driver

From: Jonathan Cameron
Date: Sat Nov 03 2018 - 07:51:18 EST

On Mon, 29 Oct 2018 17:40:25 +0530
Manish Narani <manish.narani@xxxxxxxxxx> wrote:

> The AMS includes an ADC as well as on-chip sensors that can be used to
> sample external voltages and monitor on-die operating conditions, such
> as temperature and supply voltage levels. The AMS has two SYSMON blocks.
> PL-SYSMON block is capable of monitoring off chip voltage and
> temperature.
> PL-SYSMON block has DRP, JTAG and I2C interface to enable monitoring
> from external master. Out of these interface currently only DRP is
> supported.
> Other block PS-SYSMON is memory mapped to PS.
> The AMS can use internal channels to monitor voltage and temperature as
> well as one primary and up to 16 auxiliary channels for measuring
> external voltages.
> The voltage and temperature monitoring channels also have event
> capability which allows to generate an interrupt when their value falls
> below or raises above a set threshold.
>
> Signed-off-by: Manish Narani <manish.narani@xxxxxxxxxx>

Hi Manish,

Looking pretty good. Two things:

1) There are a lot of NULLs being passed around now we have mostly
dropped the extname stuff. I would drop them from the macros.

2) I hadn't really noticed before but you set chan->address to actually
be the address of the read register, which is fine on simple devices, but
here results in a number of reverse lookups (which can't easily be
put in a static lookup table) to get to things about the channel.
Perhaps consider if this would be better done by making chan->address
an enum value (the sequence enum might work though I haven't checked) and
then move to look up tables for the actual address and related bit
positions etc. I think it might simplify the code a fair bit. Feel
free to say it doesn't if I'm wrong! It's a complex mapping in somecases
so it may not be worth the effort.

Thanks,

Jonathan

> ---
> drivers/iio/adc/Kconfig | 10 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/xilinx-ams.c | 1343 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 1354 insertions(+)
> create mode 100644 drivers/iio/adc/xilinx-ams.c
>
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 4a75492..8f7dd62 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -941,4 +941,14 @@ config XILINX_XADC
> The driver can also be build as a module. If so, the module will be called
> xilinx-xadc.
>
> +config XILINX_AMS
> + tristate "Xilinx AMS driver"
> + depends on ARCH_ZYNQMP || COMPILE_TEST
> + depends on HAS_IOMEM
> + help
> + Say yes here to have support for the Xilinx AMS.
> +
> + The driver can also be built as a module. If so, the module will be called
> + xilinx-ams.
> +
> endmenu
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 03db7b5..fbfcc45 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -85,4 +85,5 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o
> obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
> xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o
> obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o
> +obj-$(CONFIG_XILINX_AMS) += xilinx-ams.o
> obj-$(CONFIG_SD_ADC_MODULATOR) += sd_adc_modulator.o
> diff --git a/drivers/iio/adc/xilinx-ams.c b/drivers/iio/adc/xilinx-ams.c
> new file mode 100644
> index 0000000..fee1d66
> --- /dev/null
> +++ b/drivers/iio/adc/xilinx-ams.c
> @@ -0,0 +1,1343 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Xilinx AMS driver
> + *
> + * Copyright (C) 2017-2018 Xilinx, Inc.
> + *
> + * Manish Narani <mnarani@xxxxxxxxxx>
> + * Rajnikant Bhojani <rajnikant.bhojani@xxxxxxxxxx>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include <linux/iio/events.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +static const unsigned int AMS_UNMASK_TIMEOUT_MS = 500;
> +
> +/* AMS registers definitions */
> +#define AMS_ISR_0 0x010
> +#define AMS_ISR_1 0x014
> +#define AMS_IER_0 0x020
> +#define AMS_IER_1 0x024
> +#define AMS_IDR_0 0x028
> +#define AMS_IDR_1 0x02c
> +#define AMS_PS_CSTS 0x040
> +#define AMS_PL_CSTS 0x044
> +
> +#define AMS_VCC_PSPLL0 0x060
> +#define AMS_VCC_PSPLL3 0x06C
> +#define AMS_VCCINT 0x078
> +#define AMS_VCCBRAM 0x07C
> +#define AMS_VCCAUX 0x080
> +#define AMS_PSDDRPLL 0x084
> +#define AMS_PSINTFPDDR 0x09C
> +
> +#define AMS_VCC_PSPLL0_CH 48
> +#define AMS_VCC_PSPLL3_CH 51
> +#define AMS_VCCINT_CH 54
> +#define AMS_VCCBRAM_CH 55
> +#define AMS_VCCAUX_CH 56
> +#define AMS_PSDDRPLL_CH 57
> +#define AMS_PSINTFPDDR_CH 63
> +
> +#define AMS_REG_CONFIG0 0x100
> +#define AMS_REG_CONFIG1 0x104
> +#define AMS_REG_CONFIG3 0x10C
> +#define AMS_REG_SEQ_CH0 0x120
> +#define AMS_REG_SEQ_CH1 0x124
> +#define AMS_REG_SEQ_CH2 0x118
> +
> +#define AMS_TEMP 0x000
> +#define AMS_SUPPLY1 0x004
> +#define AMS_SUPPLY2 0x008
> +#define AMS_VP_VN 0x00c
> +#define AMS_VREFP 0x010
> +#define AMS_VREFN 0x014
> +#define AMS_SUPPLY3 0x018
> +#define AMS_SUPPLY4 0x034
> +#define AMS_SUPPLY5 0x038
> +#define AMS_SUPPLY6 0x03c
> +#define AMS_SUPPLY7 0x200
> +#define AMS_SUPPLY8 0x204
> +#define AMS_SUPPLY9 0x208
> +#define AMS_SUPPLY10 0x20c
> +#define AMS_VCCAMS 0x210
> +#define AMS_TEMP_REMOTE 0x214
> +
> +#define AMS_REG_VAUX(x) (0x40 + 4*(x))
> +
> +#define AMS_PS_RESET_VALUE 0xFFFF
> +#define AMS_PL_RESET_VALUE 0xFFFF
> +
> +#define AMS_CONF0_CHANNEL_NUM_MASK GENMASK(6, 0)
> +
> +#define AMS_CONF1_SEQ_MASK GENMASK(15, 12)
> +#define AMS_CONF1_SEQ_DEFAULT (0 << 12)
> +#define AMS_CONF1_SEQ_CONTINUOUS (2 << 12)
> +#define AMS_CONF1_SEQ_SINGLE_CHANNEL (3 << 12)
> +
> +#define AMS_REG_SEQ0_MASK 0xFFFF
> +#define AMS_REG_SEQ2_MASK 0x003F
> +#define AMS_REG_SEQ1_MASK 0xFFFF
> +#define AMS_REG_SEQ2_MASK_SHIFT 16
> +#define AMS_REG_SEQ1_MASK_SHIFT 22
> +
> +#define AMS_REGCFG1_ALARM_MASK 0xF0F
> +#define AMS_REGCFG3_ALARM_MASK 0x3F
> +
> +#define AMS_ALARM_TEMP 0x140
> +#define AMS_ALARM_SUPPLY1 0x144
> +#define AMS_ALARM_SUPPLY2 0x148
> +#define AMS_ALARM_SUPPLY3 0x160
> +#define AMS_ALARM_SUPPLY4 0x164
> +#define AMS_ALARM_SUPPLY5 0x168
> +#define AMS_ALARM_SUPPLY6 0x16c
> +#define AMS_ALARM_SUPPLY7 0x180
> +#define AMS_ALARM_SUPPLY8 0x184
> +#define AMS_ALARM_SUPPLY9 0x188
> +#define AMS_ALARM_SUPPLY10 0x18c
> +#define AMS_ALARM_VCCAMS 0x190
> +#define AMS_ALARM_TEMP_REMOTE 0x194
> +#define AMS_ALARM_THRESHOLD_OFF_10 0x10
> +#define AMS_ALARM_THRESHOLD_OFF_20 0x20
> +
> +#define AMS_ALARM_THR_DIRECT_MASK 0x01
> +#define AMS_ALARM_THR_MIN 0x0000
> +#define AMS_ALARM_THR_MAX 0xffff
> +
> +#define AMS_NO_OF_ALARMS 32
> +#define AMS_PL_ALARM_START 16
> +#define AMS_ISR0_ALARM_MASK 0xFFFFFFFFU
> +#define AMS_ISR1_ALARM_MASK 0xE000001FU
> +#define AMS_ISR1_EOC_MASK 0x00000008U
> +#define AMS_ISR1_INTR_MASK_SHIFT 32
> +#define AMS_ISR0_ALARM_2_TO_0_MASK 0x07
> +#define AMS_ISR0_ALARM_6_TO_3_MASK 0x78
> +#define AMS_ISR0_ALARM_12_TO_7_MASK 0x3F
> +#define AMS_CONF1_ALARM_2_TO_0_SHIFT 1
> +#define AMS_CONF1_ALARM_6_TO_3_SHIFT 5
> +#define AMS_CONF3_ALARM_12_TO_7_SHIFT 8
> +
> +#define AMS_PS_CSTS_PS_READY 0x08010000U
> +#define AMS_PL_CSTS_ACCESS_MASK 0x00000001U
> +
> +#define AMS_PL_MAX_FIXED_CHANNEL 10
> +#define AMS_PL_MAX_EXT_CHANNEL 20
> +
> +#define AMS_INIT_TIMEOUT_US 10000
> +
> +/*
> + * Following scale and offset value is derived from
> + * UG580 (v1.7) December 20, 2016
> + */
> +#define AMS_SUPPLY_SCALE_1VOLT 1000
> +#define AMS_SUPPLY_SCALE_3VOLT 3000
> +#define AMS_SUPPLY_SCALE_6VOLT 6000
> +#define AMS_SUPPLY_SCALE_DIV_BIT 16
> +
> +#define AMS_TEMP_SCALE 509314
> +#define AMS_TEMP_SCALE_DIV_BIT 16
> +#define AMS_TEMP_OFFSET -((280230L << 16) / 509314)
> +
> +enum ams_alarm_bit {
> + AMS_ALARM_BIT_TEMP,
> + AMS_ALARM_BIT_SUPPLY1,
> + AMS_ALARM_BIT_SUPPLY2,
> + AMS_ALARM_BIT_SUPPLY3,
> + AMS_ALARM_BIT_SUPPLY4,
> + AMS_ALARM_BIT_SUPPLY5,
> + AMS_ALARM_BIT_SUPPLY6,
> + AMS_ALARM_BIT_RESERVED,
> + AMS_ALARM_BIT_SUPPLY7,
> + AMS_ALARM_BIT_SUPPLY8,
> + AMS_ALARM_BIT_SUPPLY9,
> + AMS_ALARM_BIT_SUPPLY10,
> + AMS_ALARM_BIT_VCCAMS,
> + AMS_ALARM_BIT_TEMP_REMOTE
> +};
> +
> +enum ams_seq {
> + AMS_SEQ_VCC_PSPLL,
> + AMS_SEQ_VCC_PSBATT,
> + AMS_SEQ_VCCINT,
> + AMS_SEQ_VCCBRAM,
> + AMS_SEQ_VCCAUX,
> + AMS_SEQ_PSDDRPLL,
> + AMS_SEQ_INTDDR
> +};
> +
> +enum ams_ps_pl_seq {
> + AMS_SEQ_CALIB,
> + AMS_SEQ_RSVD_1,
> + AMS_SEQ_RSVD_2,
> + AMS_SEQ_TEST,
> + AMS_SEQ_RSVD_4,
> + AMS_SEQ_SUPPLY4,
> + AMS_SEQ_SUPPLY5,
> + AMS_SEQ_SUPPLY6,
> + AMS_SEQ_TEMP,
> + AMS_SEQ_SUPPLY2,
> + AMS_SEQ_SUPPLY1,
> + AMS_SEQ_VP_VN,
> + AMS_SEQ_VREFP,
> + AMS_SEQ_VREFN,
> + AMS_SEQ_SUPPLY3,
> + AMS_SEQ_CURRENT_MON,
> + AMS_SEQ_SUPPLY7,
> + AMS_SEQ_SUPPLY8,
> + AMS_SEQ_SUPPLY9,
> + AMS_SEQ_SUPPLY10,
> + AMS_SEQ_VCCAMS,
> + AMS_SEQ_TEMP_REMOTE,
> + AMS_SEQ_MAX
> +};
> +
> +#define AMS_SEQ(x) (AMS_SEQ_MAX + (x))
> +#define AMS_VAUX_SEQ(x) (AMS_SEQ_MAX + (x))
> +
> +#define AMS_PS_SEQ_MAX AMS_SEQ_MAX
> +#define PS_SEQ(x) (x)
> +#define PL_SEQ(x) (AMS_PS_SEQ_MAX + (x))
> +
> +#define AMS_CHAN_TEMP(_scan_index, _addr, _ext) { \
> + .type = IIO_TEMP, \
> + .indexed = 1, \
> + .address = (_addr), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_OFFSET), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .event_spec = ams_temp_events, \
> + .num_event_specs = ARRAY_SIZE(ams_temp_events), \
> + .scan_index = (_scan_index), \
> + .scan_type = { \
> + .sign = 'u', \
> + .realbits = 12, \
> + .storagebits = 16, \
> + .shift = 4, \
> + .endianness = IIO_CPU, \
> + }, \
> + .extend_name = _ext, \
> +}
> +
> +#define AMS_CHAN_VOLTAGE(_scan_index, _addr, _ext, _alarm) { \
> + .type = IIO_VOLTAGE, \
> + .indexed = 1, \
> + .address = (_addr), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_SCALE), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .event_spec = (_alarm) ? ams_voltage_events : NULL, \
> + .num_event_specs = (_alarm) ? ARRAY_SIZE(ams_voltage_events) : 0, \
> + .scan_index = (_scan_index), \
> + .scan_type = { \
> + .realbits = 10, \
> + .storagebits = 16, \
> + .shift = 6, \
> + .endianness = IIO_CPU, \
> + }, \
> + .extend_name = _ext, \
> +}
> +
> +#define AMS_PS_CHAN_TEMP(_scan_index, _addr, _ext) \
> + AMS_CHAN_TEMP(PS_SEQ(_scan_index), _addr, _ext)
> +#define AMS_PS_CHAN_VOLTAGE(_scan_index, _addr, _ext) \
> + AMS_CHAN_VOLTAGE(PS_SEQ(_scan_index), _addr, _ext, true)
> +
> +#define AMS_PL_CHAN_TEMP(_scan_index, _addr, _ext) \
> + AMS_CHAN_TEMP(PL_SEQ(_scan_index), _addr, _ext)
> +#define AMS_PL_CHAN_VOLTAGE(_scan_index, _addr, _ext, _alarm) \
> + AMS_CHAN_VOLTAGE(PL_SEQ(_scan_index), _addr, _ext, _alarm)
> +#define AMS_PL_AUX_CHAN_VOLTAGE(_auxno, _ext) \
> + AMS_CHAN_VOLTAGE(PL_SEQ(AMS_VAUX_SEQ(_auxno)), \
> + AMS_REG_VAUX(_auxno), _ext, false)

Given we no longer set _ext we should drop the parameter in general.
This applies to all these macros where it is no longer used.

> +#define AMS_CTRL_CHAN_VOLTAGE(_scan_index, _addr, _ext) \
> + AMS_CHAN_VOLTAGE(PL_SEQ(AMS_VAUX_SEQ(AMS_SEQ(_scan_index))), \
> + _addr, _ext, false)
> +
> +struct ams {
> + void __iomem *base;
> + void __iomem *ps_base;
> + void __iomem *pl_base;
> + struct clk *clk;
> + struct device *dev;
> + struct mutex lock;
> + unsigned int alarm_mask;
> + unsigned int masked_alarm;
> + u64 intr_mask;
> + int irq;
> + struct delayed_work ams_unmask_work;
> +};
> +
> +static inline void ams_ps_update_reg(struct ams *ams, unsigned int offset,
> + u32 mask, u32 data)
> +{
> + u32 val;
> +
> + val = readl(ams->ps_base + offset);
> + writel((val & ~mask) | (data & mask), ams->ps_base + offset);
> +}
> +
> +static inline void ams_pl_update_reg(struct ams *ams, unsigned int offset,
> + u32 mask, u32 data)
> +{
> + u32 val;
> +
> + val = readl(ams->pl_base + offset);
> + writel((val & ~mask) | (data & mask), ams->pl_base + offset);
> +}
> +
> +static void ams_update_intrmask(struct ams *ams, u64 mask, u64 val)
> +{
> + ams->intr_mask &= ~mask;
> + ams->intr_mask |= (val & mask);
> +
> + writel(~(ams->intr_mask | ams->masked_alarm), ams->base + AMS_IER_0);
> + writel(~(ams->intr_mask >> AMS_ISR1_INTR_MASK_SHIFT),
> + ams->base + AMS_IER_1);
> + writel(ams->intr_mask | ams->masked_alarm, ams->base + AMS_IDR_0);
> + writel(ams->intr_mask >> AMS_ISR1_INTR_MASK_SHIFT,
> + ams->base + AMS_IDR_1);
> +}
> +
> +static void ams_disable_all_alarms(struct ams *ams)
> +{
> + /* disable PS module alarm */
> + if (ams->ps_base) {
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_REGCFG1_ALARM_MASK,
> + AMS_REGCFG1_ALARM_MASK);
> + ams_ps_update_reg(ams, AMS_REG_CONFIG3, AMS_REGCFG3_ALARM_MASK,
> + AMS_REGCFG3_ALARM_MASK);
> + }
> +
> + /* disable PL module alarm */
> + if (ams->pl_base) {
> + ams_pl_update_reg(ams, AMS_REG_CONFIG1,
> + AMS_REGCFG1_ALARM_MASK,
> + AMS_REGCFG1_ALARM_MASK);
> + ams_pl_update_reg(ams, AMS_REG_CONFIG3,
> + AMS_REGCFG3_ALARM_MASK,
> + AMS_REGCFG3_ALARM_MASK);
> + }
> +}
> +
> +static void ams_update_alarm(struct ams *ams, unsigned long alarm_mask)
> +{
> + u32 cfg;
> + unsigned long pl_alarm_mask;
> +
> + if (ams->ps_base) {
> + /* Configuring PS alarm enable */
> + cfg = ~((alarm_mask & AMS_ISR0_ALARM_2_TO_0_MASK) <<
> + AMS_CONF1_ALARM_2_TO_0_SHIFT);
> + cfg &= ~((alarm_mask & AMS_ISR0_ALARM_6_TO_3_MASK) <<
> + AMS_CONF1_ALARM_6_TO_3_SHIFT);
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_REGCFG1_ALARM_MASK,
> + cfg);
> +
> + cfg = ~((alarm_mask >> AMS_CONF3_ALARM_12_TO_7_SHIFT) &
> + AMS_ISR0_ALARM_12_TO_7_MASK);
> + ams_ps_update_reg(ams, AMS_REG_CONFIG3, AMS_REGCFG3_ALARM_MASK,
> + cfg);
> + }
> +
> + if (ams->pl_base) {
> + pl_alarm_mask = (alarm_mask >> AMS_PL_ALARM_START);
> + /* Configuring PL alarm enable */
> + cfg = ~((pl_alarm_mask & AMS_ISR0_ALARM_2_TO_0_MASK) <<
> + AMS_CONF1_ALARM_2_TO_0_SHIFT);
> + cfg &= ~((pl_alarm_mask & AMS_ISR0_ALARM_6_TO_3_MASK) <<
> + AMS_CONF1_ALARM_6_TO_3_SHIFT);
> + ams_pl_update_reg(ams, AMS_REG_CONFIG1,
> + AMS_REGCFG1_ALARM_MASK, cfg);
> +
> + cfg = ~((pl_alarm_mask >> AMS_CONF3_ALARM_12_TO_7_SHIFT) &
> + AMS_ISR0_ALARM_12_TO_7_MASK);
> + ams_pl_update_reg(ams, AMS_REG_CONFIG3,
> + AMS_REGCFG3_ALARM_MASK, cfg);
> + }
> +
> + mutex_lock(&ams->lock);
> + ams_update_intrmask(ams, AMS_ISR0_ALARM_MASK, ~alarm_mask);
> + mutex_unlock(&ams->lock);
> +}
> +
> +static void ams_enable_channel_sequence(struct ams *ams)
> +{
> + int i;
> + unsigned long long scan_mask;
> + struct iio_dev *indio_dev = iio_priv_to_dev(ams);
> +
> + /*
> + * Enable channel sequence. First 22 bits of scan_mask represent
> + * PS channels, and next remaining bits represent PL channels.
> + */
> +
> + /* Run calibration of PS & PL as part of the sequence */
> + scan_mask = 0x1 | BIT(AMS_PS_SEQ_MAX);
> + for (i = 0; i < indio_dev->num_channels; i++)
> + scan_mask |= BIT(indio_dev->channels[i].scan_index);
> +
> + if (ams->ps_base) {
> + /* put sysmon in a soft reset to change the sequence */
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_DEFAULT);
> +
> + /* configure basic channels */
> + writel(scan_mask & AMS_REG_SEQ0_MASK,
> + ams->ps_base + AMS_REG_SEQ_CH0);
> + writel(AMS_REG_SEQ2_MASK &
> + (scan_mask >> AMS_REG_SEQ2_MASK_SHIFT),
> + ams->ps_base + AMS_REG_SEQ_CH2);
> +
> + /* set continuous sequence mode */
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_CONTINUOUS);
> + }
> +
> + if (ams->pl_base) {
> + /* put sysmon in a soft reset to change the sequence */
> + ams_pl_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_DEFAULT);
> +
> + /* configure basic channels */
> + scan_mask = scan_mask >> AMS_PS_SEQ_MAX;
> + writel(scan_mask & AMS_REG_SEQ0_MASK,
> + ams->pl_base + AMS_REG_SEQ_CH0);
> + writel(AMS_REG_SEQ2_MASK &
> + (scan_mask >> AMS_REG_SEQ2_MASK_SHIFT),
> + ams->pl_base + AMS_REG_SEQ_CH2);
> + writel(AMS_REG_SEQ1_MASK &
> + (scan_mask >> AMS_REG_SEQ1_MASK_SHIFT),
> + ams->pl_base + AMS_REG_SEQ_CH1);
> +
> + /* set continuous sequence mode */
> + ams_pl_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_CONTINUOUS);
> + }
> +}
> +
> +static int ams_init_device(struct ams *ams)
> +{
> + u32 reg;
> + int ret;
> +
> + /* reset AMS */
> + if (ams->ps_base) {
> + writel(AMS_PS_RESET_VALUE, ams->ps_base + AMS_VP_VN);
> +
> + ret = readl_poll_timeout(ams->base + AMS_PS_CSTS, reg,
> + (reg & AMS_PS_CSTS_PS_READY) ==
> + AMS_PS_CSTS_PS_READY, 0,
> + AMS_INIT_TIMEOUT_US);
> + if (ret)
> + return ret;
> +
> + /* put sysmon in a default state */
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_DEFAULT);
> + }
> +
> + if (ams->pl_base) {
> + writel(AMS_PL_RESET_VALUE, ams->pl_base + AMS_VP_VN);
> +
> + ret = readl_poll_timeout(ams->base + AMS_PL_CSTS, reg,
> + (reg & AMS_PL_CSTS_ACCESS_MASK) ==
> + AMS_PL_CSTS_ACCESS_MASK, 0,
> + AMS_INIT_TIMEOUT_US);
> + if (ret)
> + return ret;
> +
> + /* put sysmon in a default state */
> + ams_pl_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_DEFAULT);
> + }
> +
> + ams_disable_all_alarms(ams);
> +
> + /* Disable interrupt */
> + ams_update_intrmask(ams, ~0, ~0);
> +
> + /* Clear any pending interrupt */
> + writel(AMS_ISR0_ALARM_MASK, ams->base + AMS_ISR_0);
> + writel(AMS_ISR1_ALARM_MASK, ams->base + AMS_ISR_1);
> +
> + return 0;
> +}
> +
> +static int ams_enable_single_channel(struct ams *ams, unsigned int offset)
> +{
> + u8 channel_num = 0;
> +
> + switch (offset) {
> + case AMS_VCC_PSPLL0:
This lookup seems backwards. See the comment in read_raw.
It's due to having chan->address literally be the channel address. I think
perhaps it should be a more abstract value that is used to index everything
about the channel.

> + channel_num = AMS_VCC_PSPLL0_CH;
> + break;
> + case AMS_VCC_PSPLL3:
> + channel_num = AMS_VCC_PSPLL3_CH;
> + break;
> + case AMS_VCCINT:
> + channel_num = AMS_VCCINT_CH;
> + break;
> + case AMS_VCCBRAM:
> + channel_num = AMS_VCCBRAM_CH;
> + break;
> + case AMS_VCCAUX:
> + channel_num = AMS_VCCAUX_CH;
> + break;
> + case AMS_PSDDRPLL:
> + channel_num = AMS_PSDDRPLL_CH;
> + break;
> + case AMS_PSINTFPDDR:
> + channel_num = AMS_PSINTFPDDR_CH;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + /* set single channel, sequencer off mode */
> + ams_ps_update_reg(ams, AMS_REG_CONFIG1, AMS_CONF1_SEQ_MASK,
> + AMS_CONF1_SEQ_SINGLE_CHANNEL);
> +
> + /* write the channel number */
> + ams_ps_update_reg(ams, AMS_REG_CONFIG0, AMS_CONF0_CHANNEL_NUM_MASK,
> + channel_num);
> + return 0;
> +}
> +
> +static int ams_read_vcc_reg(struct ams *ams, unsigned int offset, u32 *data)
> +{
> + u32 reg;
> + int ret;
> +
> + ret = ams_enable_single_channel(ams, offset);
> + if (ret)
> + return ret;
> +
> + ret = readl_poll_timeout(ams->base + AMS_ISR_1, reg,
> + (reg & AMS_ISR1_EOC_MASK) == AMS_ISR1_EOC_MASK,
> + 0, AMS_INIT_TIMEOUT_US);
> + if (ret)
> + return ret;
> +
> + *data = readl(ams->base + offset);
> + ams_enable_channel_sequence(ams);
> +
> + return 0;
> +}
> +
> +static int ams_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + mutex_lock(&ams->lock);
> + if (chan->scan_index >= (AMS_PS_SEQ_MAX * 3)) {
> + ret = ams_read_vcc_reg(ams, chan->address, val);
There are a few places where you end up reverse looking up from the channel
address to other things which is nasty. Perhaps consider setting
chan->address to the sequence enum them some of those at least can
become simple look up tables. One of which gives the register address.


> + if (ret) {
> + mutex_unlock(&ams->lock);
> + return -EINVAL;
> + }
> + } else if (chan->scan_index >= AMS_PS_SEQ_MAX)
> + *val = readl(ams->pl_base + chan->address);
> + else
> + *val = readl(ams->ps_base + chan->address);
> + mutex_unlock(&ams->lock);
> +
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
> + case IIO_VOLTAGE:
> + switch (chan->address) {
> + case AMS_SUPPLY1:
> + case AMS_SUPPLY2:
> + case AMS_SUPPLY3:
> + case AMS_SUPPLY4:
> + *val = AMS_SUPPLY_SCALE_3VOLT;
> + break;
> + case AMS_SUPPLY5:
> + case AMS_SUPPLY6:
> + if (chan->scan_index < AMS_PS_SEQ_MAX)
> + *val = AMS_SUPPLY_SCALE_6VOLT;
> + else
> + *val = AMS_SUPPLY_SCALE_3VOLT;
> + break;
> + case AMS_SUPPLY7:
> + case AMS_SUPPLY8:
> + *val = AMS_SUPPLY_SCALE_6VOLT;
> + break;
> + case AMS_SUPPLY9:
> + case AMS_SUPPLY10:
> + if (chan->scan_index < AMS_PS_SEQ_MAX)
> + *val = AMS_SUPPLY_SCALE_3VOLT;
> + else
> + *val = AMS_SUPPLY_SCALE_6VOLT;
> + break;
> + case AMS_VCC_PSPLL0:
> + case AMS_VCC_PSPLL3:
> + case AMS_VCCINT:
> + case AMS_VCCBRAM:
> + case AMS_VCCAUX:
> + case AMS_PSDDRPLL:
> + case AMS_PSINTFPDDR:
> + *val = AMS_SUPPLY_SCALE_3VOLT;
> + break;
> + default:
> + *val = AMS_SUPPLY_SCALE_1VOLT;
> + break;
> + }
> + *val2 = AMS_SUPPLY_SCALE_DIV_BIT;
> + return IIO_VAL_FRACTIONAL_LOG2;
> + case IIO_TEMP:
> + *val = AMS_TEMP_SCALE;
> + *val2 = AMS_TEMP_SCALE_DIV_BIT;
> + return IIO_VAL_FRACTIONAL_LOG2;
> + default:
> + return -EINVAL;
> + }
> + case IIO_CHAN_INFO_OFFSET:
> + /* Only the temperature channel has an offset */
> + *val = AMS_TEMP_OFFSET;
> + return IIO_VAL_INT;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int ams_get_alarm_offset(int scan_index, enum iio_event_direction dir)
> +{
> + int offset = 0;
> +
> + if (scan_index >= AMS_PS_SEQ_MAX)
> + scan_index -= AMS_PS_SEQ_MAX;
> +
> + if (dir == IIO_EV_DIR_FALLING) {
> + if (scan_index < AMS_SEQ_SUPPLY7)
> + offset = AMS_ALARM_THRESHOLD_OFF_10;
> + else
> + offset = AMS_ALARM_THRESHOLD_OFF_20;
> + }
> +
> + switch (scan_index) {

Not sure why I didn't comment on this before, but this
looks awfully like a case for a look up table rather than the
switch statement of doom.

There are a few other places where this is true in the code
and some of them can be easily combined into one array
(e.g address and bit) The event to channel one below
though is a hot path so you'll either need the reverse table
as well, or just leave that one as a huge switch statement.

> + case AMS_SEQ_TEMP:
> + return AMS_ALARM_TEMP + offset;
> + case AMS_SEQ_SUPPLY1:
> + return AMS_ALARM_SUPPLY1 + offset;
> + case AMS_SEQ_SUPPLY2:
> + return AMS_ALARM_SUPPLY2 + offset;
> + case AMS_SEQ_SUPPLY3:
> + return AMS_ALARM_SUPPLY3 + offset;
> + case AMS_SEQ_SUPPLY4:
> + return AMS_ALARM_SUPPLY4 + offset;
> + case AMS_SEQ_SUPPLY5:
> + return AMS_ALARM_SUPPLY5 + offset;
> + case AMS_SEQ_SUPPLY6:
> + return AMS_ALARM_SUPPLY6 + offset;
> + case AMS_SEQ_SUPPLY7:
> + return AMS_ALARM_SUPPLY7 + offset;
> + case AMS_SEQ_SUPPLY8:
> + return AMS_ALARM_SUPPLY8 + offset;
> + case AMS_SEQ_SUPPLY9:
> + return AMS_ALARM_SUPPLY9 + offset;
> + case AMS_SEQ_SUPPLY10:
> + return AMS_ALARM_SUPPLY10 + offset;
> + case AMS_SEQ_VCCAMS:
> + return AMS_ALARM_VCCAMS + offset;
> + case AMS_SEQ_TEMP_REMOTE:
> + return AMS_ALARM_TEMP_REMOTE + offset;
> + }
> +
> + return 0;
> +}
> +
> +static const struct iio_chan_spec *ams_event_to_channel(
> + struct iio_dev *indio_dev, u32 event)
> +{
> + int scan_index = 0, i;
> +
> + if (event >= AMS_PL_ALARM_START) {
> + event -= AMS_PL_ALARM_START;
> + scan_index = AMS_PS_SEQ_MAX;
> + }
> +
> + switch (event) {
> + case AMS_ALARM_BIT_TEMP:
> + scan_index += AMS_SEQ_TEMP;
> + break;
> + case AMS_ALARM_BIT_SUPPLY1:
> + scan_index += AMS_SEQ_SUPPLY1;
> + break;
> + case AMS_ALARM_BIT_SUPPLY2:
> + scan_index += AMS_SEQ_SUPPLY2;
> + break;
> + case AMS_ALARM_BIT_SUPPLY3:
> + scan_index += AMS_SEQ_SUPPLY3;
> + break;
> + case AMS_ALARM_BIT_SUPPLY4:
> + scan_index += AMS_SEQ_SUPPLY4;
> + break;
> + case AMS_ALARM_BIT_SUPPLY5:
> + scan_index += AMS_SEQ_SUPPLY5;
> + break;
> + case AMS_ALARM_BIT_SUPPLY6:
> + scan_index += AMS_SEQ_SUPPLY6;
> + break;
> + case AMS_ALARM_BIT_SUPPLY7:
> + scan_index += AMS_SEQ_SUPPLY7;
> + break;
> + case AMS_ALARM_BIT_SUPPLY8:
> + scan_index += AMS_SEQ_SUPPLY8;
> + break;
> + case AMS_ALARM_BIT_SUPPLY9:
> + scan_index += AMS_SEQ_SUPPLY9;
> + break;
> + case AMS_ALARM_BIT_SUPPLY10:
> + scan_index += AMS_SEQ_SUPPLY10;
> + break;
> + case AMS_ALARM_BIT_VCCAMS:
> + scan_index += AMS_SEQ_VCCAMS;
> + break;
> + case AMS_ALARM_BIT_TEMP_REMOTE:
> + scan_index += AMS_SEQ_TEMP_REMOTE;
> + break;
> + }
> +
> + for (i = 0; i < indio_dev->num_channels; i++)
> + if (indio_dev->channels[i].scan_index == scan_index)
> + break;
> +
> + return &indio_dev->channels[i];
> +}
> +
> +static int ams_get_alarm_mask(int scan_index)
> +{
> + int bit = 0;
> +
> + if (scan_index >= AMS_PS_SEQ_MAX) {
> + bit = AMS_PL_ALARM_START;
> + scan_index -= AMS_PS_SEQ_MAX;
> + }
> +
> + switch (scan_index) {
> + case AMS_SEQ_TEMP:
> + return BIT(AMS_ALARM_BIT_TEMP + bit);
> + case AMS_SEQ_SUPPLY1:
> + return BIT(AMS_ALARM_BIT_SUPPLY1 + bit);
> + case AMS_SEQ_SUPPLY2:
> + return BIT(AMS_ALARM_BIT_SUPPLY2 + bit);
> + case AMS_SEQ_SUPPLY3:
> + return BIT(AMS_ALARM_BIT_SUPPLY3 + bit);
> + case AMS_SEQ_SUPPLY4:
> + return BIT(AMS_ALARM_BIT_SUPPLY4 + bit);
> + case AMS_SEQ_SUPPLY5:
> + return BIT(AMS_ALARM_BIT_SUPPLY5 + bit);
> + case AMS_SEQ_SUPPLY6:
> + return BIT(AMS_ALARM_BIT_SUPPLY6 + bit);
> + case AMS_SEQ_SUPPLY7:
> + return BIT(AMS_ALARM_BIT_SUPPLY7 + bit);
> + case AMS_SEQ_SUPPLY8:
> + return BIT(AMS_ALARM_BIT_SUPPLY8 + bit);
> + case AMS_SEQ_SUPPLY9:
> + return BIT(AMS_ALARM_BIT_SUPPLY9 + bit);
> + case AMS_SEQ_SUPPLY10:
> + return BIT(AMS_ALARM_BIT_SUPPLY10 + bit);
> + case AMS_SEQ_VCCAMS:
> + return BIT(AMS_ALARM_BIT_VCCAMS + bit);
> + case AMS_SEQ_TEMP_REMOTE:
> + return BIT(AMS_ALARM_BIT_TEMP_REMOTE + bit);
> + }
> +
> + return 0;
> +}
> +
> +static int ams_read_event_config(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + enum iio_event_type type,
> + enum iio_event_direction dir)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> +
> + return (ams->alarm_mask & ams_get_alarm_mask(chan->scan_index)) ? 1 : 0;
Huh. My initial assumption was that we wouldn't need to force this to 1 or
0 because surely the core would do that. oops it doesn't. Just outputs
the value directly to userspace.

I hope there is no userspace actually taking advantage of that little
delight. One for the list of things to clean up in the core, but for
now this is correct.

> +}
> +
> +static int ams_write_event_config(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + enum iio_event_type type,
> + enum iio_event_direction dir,
> + int state)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + unsigned int alarm;
> +
> + alarm = ams_get_alarm_mask(chan->scan_index);
> +
> + mutex_lock(&ams->lock);
> +
> + if (state)
> + ams->alarm_mask |= alarm;
> + else
> + ams->alarm_mask &= ~alarm;
> +
> + ams_update_alarm(ams, ams->alarm_mask);
> +
> + mutex_unlock(&ams->lock);
> +
> + return 0;
> +}
> +
> +static int ams_read_event_value(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + enum iio_event_type type,
> + enum iio_event_direction dir,
> + enum iio_event_info info, int *val, int *val2)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + unsigned int offset = ams_get_alarm_offset(chan->scan_index, dir);
> +
> + mutex_lock(&ams->lock);
> +
> + if (chan->scan_index >= AMS_PS_SEQ_MAX)
> + *val = readl(ams->pl_base + offset);
> + else
> + *val = readl(ams->ps_base + offset);
> +
> + mutex_unlock(&ams->lock);
> +
> + return IIO_VAL_INT;
> +}
> +
> +static int ams_write_event_value(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + enum iio_event_type type,
> + enum iio_event_direction dir,
> + enum iio_event_info info, int val, int val2)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + unsigned int offset;
> +
> + mutex_lock(&ams->lock);
> +
> + /* Set temperature channel threshold to direct threshold */
> + if (chan->type == IIO_TEMP) {
> + offset = ams_get_alarm_offset(chan->scan_index,
> + IIO_EV_DIR_FALLING);
> +
> + if (chan->scan_index >= AMS_PS_SEQ_MAX)
> + ams_pl_update_reg(ams, offset,
> + AMS_ALARM_THR_DIRECT_MASK,
> + AMS_ALARM_THR_DIRECT_MASK);
> + else
> + ams_ps_update_reg(ams, offset,
> + AMS_ALARM_THR_DIRECT_MASK,
> + AMS_ALARM_THR_DIRECT_MASK);
> + }
> +
> + offset = ams_get_alarm_offset(chan->scan_index, dir);
> + if (chan->scan_index >= AMS_PS_SEQ_MAX)
> + writel(val, ams->pl_base + offset);
> + else
> + writel(val, ams->ps_base + offset);
> +
> + mutex_unlock(&ams->lock);
> +
> + return 0;
> +}
> +
> +static void ams_handle_event(struct iio_dev *indio_dev, u32 event)
> +{
> + const struct iio_chan_spec *chan;
> +
> + chan = ams_event_to_channel(indio_dev, event);
> +
> + if (chan->type == IIO_TEMP) {
> + /*
> + * The temperature channel only supports over-temperature
> + * events
> + */
> + iio_push_event(indio_dev,
> + IIO_UNMOD_EVENT_CODE(chan->type, chan->channel,
> + IIO_EV_TYPE_THRESH,
> + IIO_EV_DIR_RISING),
> + iio_get_time_ns(indio_dev));
> + } else {
> + /*
> + * For other channels we don't know whether it is a upper or
> + * lower threshold event. Userspace will have to check the
> + * channel value if it wants to know.
> + */
> + iio_push_event(indio_dev,
> + IIO_UNMOD_EVENT_CODE(chan->type, chan->channel,
> + IIO_EV_TYPE_THRESH,
> + IIO_EV_DIR_EITHER),
> + iio_get_time_ns(indio_dev));
> + }
> +}
> +
> +static void ams_handle_events(struct iio_dev *indio_dev, unsigned long events)
> +{
> + unsigned int bit;
> +
> + for_each_set_bit(bit, &events, AMS_NO_OF_ALARMS)
> + ams_handle_event(indio_dev, bit);
> +}
> +
> +/**
> + * ams_unmask_worker - ams alarm interrupt unmask worker
> + * @work : work to be done
> + *
> + * The ZynqMP threshold interrupts are level sensitive. Since we can't make the
> + * threshold condition go way from within the interrupt handler, this means as
> + * soon as a threshold condition is present we would enter the interrupt handler
> + * again and again. To work around this we mask all active threshold interrupts
> + * in the interrupt handler and start a timer. In this timer we poll the
> + * interrupt status and only if the interrupt is inactive we unmask it again.
> + */
> +static void ams_unmask_worker(struct work_struct *work)
> +{
> + struct ams *ams = container_of(work, struct ams, ams_unmask_work.work);
> + unsigned int status, unmask;
> +
> + mutex_lock(&ams->lock);
> +
> + status = readl(ams->base + AMS_ISR_0);
> +
> + /* Clear those bits which are not active anymore */
> + unmask = (ams->masked_alarm ^ status) & ams->masked_alarm;
> +
> + /* clear status of disabled alarm */
> + unmask |= ams->intr_mask;
> +
> + ams->masked_alarm &= status;
> +
> + /* Also clear those which are masked out anyway */
> + ams->masked_alarm &= ~ams->intr_mask;
> +
> + /* Clear the interrupts before we unmask them */
> + writel(unmask, ams->base + AMS_ISR_0);
> +
> + ams_update_intrmask(ams, 0, 0);
> +
> + mutex_unlock(&ams->lock);
> +
> + /* if still pending some alarm re-trigger the timer */
> + if (ams->masked_alarm)
> + schedule_delayed_work(&ams->ams_unmask_work,
> + msecs_to_jiffies(AMS_UNMASK_TIMEOUT_MS));
> +}
> +
> +static irqreturn_t ams_irq(int irq, void *data)
> +{
> + struct iio_dev *indio_dev = data;
> + struct ams *ams = iio_priv(indio_dev);
> + u32 isr0;
> +
> + isr0 = readl(ams->base + AMS_ISR_0);
> +
> + /* only process alarms that are not masked */
> + isr0 &= ~((ams->intr_mask & AMS_ISR0_ALARM_MASK) | ams->masked_alarm);
> +
> + if (!isr0)
> + return IRQ_NONE;
> +
> + /* clear interrupt */
> + writel(isr0, ams->base + AMS_ISR_0);
> +
> + /* Mask the alarm interrupts until cleared */
> + ams->masked_alarm |= isr0;
> + ams_update_intrmask(ams, 0, 0);
> +
> + ams_handle_events(indio_dev, isr0);
> +
> + schedule_delayed_work(&ams->ams_unmask_work,
> + msecs_to_jiffies(AMS_UNMASK_TIMEOUT_MS));
> +
> + return IRQ_HANDLED;
> +}
> +
> +static const struct iio_event_spec ams_temp_events[] = {
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_RISING,
> + .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
> + BIT(IIO_EV_INFO_VALUE),
> + },
> +};
> +
> +static const struct iio_event_spec ams_voltage_events[] = {
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_RISING,
> + .mask_separate = BIT(IIO_EV_INFO_VALUE),
> + },
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_FALLING,
> + .mask_separate = BIT(IIO_EV_INFO_VALUE),
> + },
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_EITHER,
> + .mask_separate = BIT(IIO_EV_INFO_ENABLE),
> + },
> +};
> +
> +static const struct iio_chan_spec ams_ps_channels[] = {
> + AMS_PS_CHAN_TEMP(AMS_SEQ_TEMP, AMS_TEMP, NULL),
> + AMS_PS_CHAN_TEMP(AMS_SEQ_TEMP_REMOTE, AMS_TEMP_REMOTE, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY1, AMS_SUPPLY1, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY2, AMS_SUPPLY2, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY3, AMS_SUPPLY3, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY4, AMS_SUPPLY4, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY5, AMS_SUPPLY5, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY6, AMS_SUPPLY6, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY7, AMS_SUPPLY7, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY8, AMS_SUPPLY8, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY9, AMS_SUPPLY9, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_SUPPLY10, AMS_SUPPLY10, NULL),
> + AMS_PS_CHAN_VOLTAGE(AMS_SEQ_VCCAMS, AMS_VCCAMS, NULL),
> +};
> +
> +static const struct iio_chan_spec ams_pl_channels[] = {
> + AMS_PL_CHAN_TEMP(AMS_SEQ_TEMP, AMS_TEMP, NULL),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY1, AMS_SUPPLY1, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY2, AMS_SUPPLY2, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_VREFP, AMS_VREFP, NULL, false),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_VREFN, AMS_VREFN, NULL, false),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY3, AMS_SUPPLY3, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY4, AMS_SUPPLY4, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY5, AMS_SUPPLY5, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY6, AMS_SUPPLY6, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_VCCAMS, AMS_VCCAMS, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_VP_VN, AMS_VP_VN, NULL, false),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY7, AMS_SUPPLY7, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY8, AMS_SUPPLY8, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY9, AMS_SUPPLY9, NULL, true),
> + AMS_PL_CHAN_VOLTAGE(AMS_SEQ_SUPPLY10, AMS_SUPPLY10, NULL, true),
> + AMS_PL_AUX_CHAN_VOLTAGE(0, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(1, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(2, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(3, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(4, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(5, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(6, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(7, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(8, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(9, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(10, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(11, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(12, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(13, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(14, NULL),
> + AMS_PL_AUX_CHAN_VOLTAGE(15, NULL),
> +};
> +
> +static const struct iio_chan_spec ams_ctrl_channels[] = {
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_VCC_PSPLL, AMS_VCC_PSPLL0, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_VCC_PSBATT, AMS_VCC_PSPLL3, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_VCCINT, AMS_VCCINT, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_VCCBRAM, AMS_VCCBRAM, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_VCCAUX, AMS_VCCAUX, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_PSDDRPLL, AMS_PSDDRPLL, NULL),
> + AMS_CTRL_CHAN_VOLTAGE(AMS_SEQ_INTDDR, AMS_PSINTFPDDR, NULL),
> +};
> +
> +static int ams_get_ext_chan(struct device_node *chan_node,
> + struct iio_chan_spec *channels, int num_channels)
> +{
> + struct device_node *child;
> + unsigned int reg;
> + int ret;
> +
> + for_each_child_of_node(chan_node, child) {
> + ret = of_property_read_u32(child, "reg", &reg);
> + if (ret || reg > AMS_PL_MAX_EXT_CHANNEL)
> + continue;
> +
> + memcpy(&channels[num_channels], &ams_pl_channels[reg +
> + AMS_PL_MAX_FIXED_CHANNEL], sizeof(*channels));
> +
> + if (of_property_read_bool(child,
> + "xlnx,bipolar"))
> + channels[num_channels].scan_type.sign = 's';
> +
> + num_channels++;
> + }
> +
> + return num_channels;
> +}
> +
> +static int ams_init_module(struct iio_dev *indio_dev, struct device_node *np,
> + struct iio_chan_spec *channels)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + struct device_node *chan_node;
> + int num_channels = 0;
> +
> + if (of_device_is_compatible(np, "xlnx,zynqmp-ams-ps")) {
> + ams->ps_base = of_iomap(np, 0);
> + if (!ams->ps_base)
> + return -ENXIO;
> +
> + /* add PS channels to iio device channels */
> + memcpy(channels + num_channels, ams_ps_channels,
> + sizeof(ams_ps_channels));
> + num_channels += ARRAY_SIZE(ams_ps_channels);
> + } else if (of_device_is_compatible(np, "xlnx,zynqmp-ams-pl")) {
> + ams->pl_base = of_iomap(np, 0);
> + if (!ams->pl_base)
> + return -ENXIO;
> +
> + /* Copy only first 10 fix channels */
> + memcpy(channels + num_channels, ams_pl_channels,
> + AMS_PL_MAX_FIXED_CHANNEL * sizeof(*channels));
> + num_channels += AMS_PL_MAX_FIXED_CHANNEL;
> +
> + chan_node = of_get_child_by_name(np, "xlnx,ext-channels");
> + if (chan_node)
> + num_channels = ams_get_ext_chan(chan_node, channels,
> + num_channels);
> +
> + of_node_put(chan_node);
> + } else if (of_device_is_compatible(np, "xlnx,zynqmp-ams")) {
> + /* add AMS channels to iio device channels */
> + memcpy(channels + num_channels, ams_ctrl_channels,
> + sizeof(ams_ctrl_channels));
> + num_channels += ARRAY_SIZE(ams_ctrl_channels);
> + } else {
> + return -EINVAL;
> + }
> +
> + return num_channels;
> +}
> +
> +static int ams_parse_dt(struct iio_dev *indio_dev, struct platform_device *pdev)
> +{
> + struct ams *ams = iio_priv(indio_dev);
> + struct iio_chan_spec *ams_channels, *dev_channels;
> + struct device_node *child_node = NULL, *np = pdev->dev.of_node;
> + int ret, vol_ch_cnt = 0, temp_ch_cnt = 0, i, rising_off, falling_off;
> + unsigned int num_channels = 0;
> +
> + /* Initialize buffer for channel specification */
> + ams_channels = kzalloc(sizeof(ams_ps_channels) +
> + sizeof(ams_pl_channels) +
> + sizeof(ams_ctrl_channels), GFP_KERNEL);
> + if (!ams_channels)
> + return -ENOMEM;
> +
> + if (of_device_is_available(np)) {
> + ret = ams_init_module(indio_dev, np, ams_channels);
> + if (ret < 0)
> + goto err;
> +
> + num_channels += ret;
> + }
> +
> + for_each_child_of_node(np, child_node) {
> + if (of_device_is_available(child_node)) {
> + ret = ams_init_module(indio_dev, child_node,
> + ams_channels + num_channels);
> + if (ret < 0)
> + goto err;
> +
> + num_channels += ret;
> + }
> + }
> +
> + for (i = 0; i < num_channels; i++) {
> + if (ams_channels[i].type == IIO_VOLTAGE)
> + ams_channels[i].channel = vol_ch_cnt++;
> + else
> + ams_channels[i].channel = temp_ch_cnt++;
> +
> + if (ams_channels[i].scan_index < (AMS_PS_SEQ_MAX * 3)) {
> + /* set threshold to max and min for each channel */
> + falling_off = ams_get_alarm_offset(
> + ams_channels[i].scan_index,
> + IIO_EV_DIR_FALLING);
> + rising_off = ams_get_alarm_offset(
> + ams_channels[i].scan_index,
> + IIO_EV_DIR_RISING);
> + if (ams_channels[i].scan_index >= AMS_PS_SEQ_MAX) {
> + writel(AMS_ALARM_THR_MIN,
> + ams->pl_base + falling_off);
> + writel(AMS_ALARM_THR_MAX,
> + ams->pl_base + rising_off);
> + } else {
> + writel(AMS_ALARM_THR_MIN,
> + ams->ps_base + falling_off);
> + writel(AMS_ALARM_THR_MAX,
> + ams->ps_base + rising_off);
> + }
> + }
> + }
> +
> + dev_channels = devm_kzalloc(&pdev->dev, sizeof(*dev_channels) *
> + num_channels, GFP_KERNEL);
> + if (!dev_channels) {
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + memcpy(dev_channels, ams_channels,
> + sizeof(*ams_channels) * num_channels);
> + indio_dev->channels = dev_channels;
> + indio_dev->num_channels = num_channels;
> +
> + ret = 0;
> +err:
> + kfree(ams_channels);
> +
> + return ret;
> +}
> +
> +static const struct iio_info iio_pl_info = {
> + .read_raw = &ams_read_raw,
> + .read_event_config = &ams_read_event_config,
> + .write_event_config = &ams_write_event_config,
> + .read_event_value = &ams_read_event_value,
> + .write_event_value = &ams_write_event_value,
> +};
> +
> +static const struct of_device_id ams_of_match_table[] = {
> + { .compatible = "xlnx,zynqmp-ams" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, ams_of_match_table);
> +
> +static int ams_probe(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev;
> + struct ams *ams;
> + struct resource *res;
> + int ret;
> +
> + if (!pdev->dev.of_node)
> + return -ENODEV;
> +
> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*ams));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + ams = iio_priv(indio_dev);
> + mutex_init(&ams->lock);
> +
> + indio_dev->dev.parent = &pdev->dev;
> + indio_dev->dev.of_node = pdev->dev.of_node;
> + indio_dev->name = "xilinx-ams";
> +
> + indio_dev->info = &iio_pl_info;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ams-base");
> + ams->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(ams->base))
> + return PTR_ERR(ams->base);
> +
> + ams->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(ams->clk))
> + return PTR_ERR(ams->clk);
> + clk_prepare_enable(ams->clk);
> +
> + INIT_DELAYED_WORK(&ams->ams_unmask_work, ams_unmask_worker);
> +
> + ret = ams_init_device(ams);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to initialize AMS\n");
> + goto err_probe;
> + }
> +
> + ret = ams_parse_dt(indio_dev, pdev);
> + if (ret) {
> + dev_err(&pdev->dev, "failure in parsing DT\n");
> + goto err_probe;
> + }
> +
> + ams_enable_channel_sequence(ams);
> +
> + ams->irq = platform_get_irq_byname(pdev, "ams-irq");
> + ret = request_irq(ams->irq, &ams_irq, 0, "ams-irq", indio_dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to register interrupt\n");
> + goto err_probe;
> + }
> +
> + platform_set_drvdata(pdev, indio_dev);
> +
> + ret = iio_device_register(indio_dev);
> + if (ret)
> + goto err_irq_free;
> +
> + return 0;
> +
> +err_irq_free:
> + free_irq(ams->irq, indio_dev);
> +
> +err_probe:
> + cancel_delayed_work(&ams->ams_unmask_work);
> + clk_disable_unprepare(ams->clk);
> +
> + return ret;
> +}
> +
> +static int ams_remove(struct platform_device *pdev)
> +{
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> + struct ams *ams = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> + free_irq(ams->irq, indio_dev);
> + cancel_delayed_work(&ams->ams_unmask_work);
> + clk_disable_unprepare(ams->clk);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused ams_suspend(struct device *dev)
> +{
> + struct ams *ams = iio_priv(dev_get_drvdata(dev));
> +
> + clk_disable_unprepare(ams->clk);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused ams_resume(struct device *dev)
> +{
> + struct ams *ams = iio_priv(dev_get_drvdata(dev));
> +
> + clk_prepare_enable(ams->clk);
> +
> + return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(ams_pm_ops, ams_suspend, ams_resume);
> +
> +static struct platform_driver ams_driver = {
> + .probe = ams_probe,
> + .remove = ams_remove,
> + .driver = {
> + .name = "xilinx-ams",
> + .pm = &ams_pm_ops,
> + .of_match_table = ams_of_match_table,
> + },
> +};
> +module_platform_driver(ams_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Xilinx, Inc.");