* Re: [PATCH v3] adc: add adc driver for Hisilicon BVT SOCs
[not found] <1487676119-107752-1-git-send-email-liurenzhong@hisilicon.com>
@ 2017-02-25 18:20 ` Jonathan Cameron
0 siblings, 0 replies; only message in thread
From: Jonathan Cameron @ 2017-02-25 18:20 UTC (permalink / raw)
To: Allen Liu, knaack.h, lars, pmeerw, robh+dt, Mark Rutland
Cc: akinobu.mita, ludovic.desroches, krzk, vilhelm.gray,
ksenija.stanojevic, zhiyong.tao, ray.jui, raveendra.padasalagi,
mranostay, amsfield22, xuejiancheng, kevin.lixu,
linux-iio@vger.kernel.org
On 21/02/17 11:21, Allen Liu wrote:
> This patch adds new driver to support:
> 1. Support ADC IF found on Hi3516CV300 and future SoCs from Hisilicon BVT
Ah, as this expected on future generations, it is fine to have the
indirection in the driver.
> 2. Add ADC driver under iio/adc framework
> 3. Also adds the documentation for device tree bindings
>
> Relative to v2, this patch do same correction:
> 1.Drop the data_v1 structure.
> 2.Add some necessary instruction, such as timescan, etc.
>
> Reviewed-by: Kevin Li <kevin.lixu@hisilicon.com>
> Signed-off-by: Allen Liu <liurenzhong@hisilicon.com>
Hi Allen,
You've managed to cc a lot of relevant people, but drop the mailing list.
If nothing else that meant I nearly missed this entirely as I tend to be
more on top of stuff via the list than my own email :)
Anyhow, added linux-iio back in.
Even though the devicetree binding is simple, I think it has enough
complexity that I need to give the devicetree maintainers time to
review it.
You have addressed all of Rob's comments though so it should just be
a case of him having time to take one last look.
A few minor stylistic comments inline that I missed on previous reviews.
Sorry about that!
Please clean those up and post a v4. It won't matter if Rob gets back
on this version in the meantime as the device tree bindings will be
unaffected.
Jonathan
> ---
> .../devicetree/bindings/iio/adc/hibvt-lsadc.txt | 24 ++
> drivers/iio/adc/Kconfig | 10 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/hibvt_lsadc.c | 344 +++++++++++++++++++++
> 4 files changed, 379 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
> create mode 100644 drivers/iio/adc/hibvt_lsadc.c
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt b/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
> new file mode 100644
> index 0000000..5c7f859
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/hibvt-lsadc.txt
> @@ -0,0 +1,24 @@
> +Hisilicon BVT Low Speed (LS) A/D Converter bindings
> +
> +Required properties:
> +- compatible: should be "hisilicon,<name>-lsadc"
> + - "hisilicon,hi3516cv300-lsadc": for hi3516cv300
> +
> +- reg: physical base address of the controller and length of memory mapped
> + region.
> +- interrupts: The interrupt number for the ADC device.
> + see .../interrupt-controller/interrupts.txt for details.
> +
> +Optional properties:
> +- resets: Must contain an entry for each entry in reset-names if need support
> + this option. See .../reset/reset.txt for details.
> +- reset-names: Must include the name "lsadc-crg".
> +
> +Example:
> + adc: adc@120e0000 {
> + compatible = "hisilicon,hi3516cv300-lsadc";
> + reg = <0x120e0000 0x1000>;
> + interrupts = <19>;
> + resets = <&crg 0x7c 3>;
> + reset-names = "lsadc-crg";
> + };
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 99c0514..0443f51 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -225,6 +225,16 @@ config HI8435
> This driver can also be built as a module. If so, the module will be
> called hi8435.
>
> +config HIBVT_LSADC
> + tristate "HIBVT LSADC driver"
> + depends on ARCH_HISI || COMPILE_TEST
> + help
> + Say yes here to build support for the LSADC found in SoCs from
> + hisilicon BVT chip.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called hibvt_lsadc.
> +
> config INA2XX_ADC
> tristate "Texas Instruments INA2xx Power Monitors IIO driver"
> depends on I2C && !SENSORS_INA2XX
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 7a40c04..6554d92 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
> obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
> obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
> obj-$(CONFIG_HI8435) += hi8435.o
> +obj-$(CONFIG_HIBVT_LSADC) += hibvt_lsadc.o
> obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
> obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
> obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
> diff --git a/drivers/iio/adc/hibvt_lsadc.c b/drivers/iio/adc/hibvt_lsadc.c
> new file mode 100644
> index 0000000..abf9724
> --- /dev/null
> +++ b/drivers/iio/adc/hibvt_lsadc.c
> @@ -0,0 +1,344 @@
> +/*
> + * Hisilicon BVT Low Speed (LS) A/D Converter
> + * Copyright (C) 2016 HiSilicon Technologies Co., Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/clk.h>
> +#include <linux/completion.h>
> +#include <linux/delay.h>
> +#include <linux/reset.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/iio/iio.h>
> +
> +/* hisilicon bvt adc registers definitions */
> +#define HIBVT_LSADC_CONFIG 0x00
> +#define HIBVT_CONFIG_DEGLITCH BIT(17)
> +#define HIBVT_CONFIG_RESET BIT(15)
> +#define HIBVT_CONFIG_POWERDOWN BIT(14)
> +#define HIBVT_CONFIG_MODE BIT(13)
> +#define HIBVT_CONFIG_CHNC BIT(10)
> +#define HIBVT_CONFIG_CHNB BIT(9)
> +#define HIBVT_CONFIG_CHNA BIT(8)
> +
> +#define HIBVT_LSADC_TIMESCAN 0x08
> +#define HIBVT_LSADC_INTEN 0x10
> +#define HIBVT_LSADC_INTSTATUS 0x14
> +#define HIBVT_LSADC_INTCLR 0x18
> +#define HIBVT_LSADC_START 0x1C
> +#define HIBVT_LSADC_STOP 0x20
> +#define HIBVT_LSADC_ACTBIT 0x24
> +#define HIBVT_LSADC_CHNDATA 0x2C
> +
> +#define HIBVT_LSADC_CON_EN (1u << 0)
> +#define HIBVT_LSADC_CON_DEN (0u << 0)
> +
> +/* Default sample precision is 10 bit */
> +#define HIBVT_LSADC_NUM_BITS 10
> +
> +#define HIBVT_LSADC_CHN_MASK 0x7
> +
> +/*
> + * The time scan is the time interval when hisilicon bvt adc work
> + * in continuous scanning mode, see hi35xx soc doc for more detail.
> + * fix clk:3000000, default tscan set 10ms
> + */
> +#define HIBVT_LSADC_TSCAN_MS (10*3000)
> +
> +#define HIBVT_LSADC_TIMEOUT msecs_to_jiffies(100)
> +
> +/*
> + * An internal regulator for the voltage scale is 3.3v or 1.8v.
> + * default voltage scale for every channel <mv>
> + */
> +static int g_hibvt_lsadc_voltage[] = {
> + 3300, 3300, 3300
> +};
> +
> +struct hibvt_lsadc {
> + void __iomem *regs;
> + struct completion completion;
> + struct reset_control *reset;
> + const struct hibvt_lsadc_data *data;
> + unsigned int cur_chn;
> + unsigned int value;
> +};
> +
> +struct hibvt_lsadc_data {
> + int num_bits;
> + const struct iio_chan_spec *channels;
> + int num_channels;
> +
> + void (*clear_irq)(struct hibvt_lsadc *info, int mask);
> + void (*start_conv)(struct hibvt_lsadc *info);
> + void (*stop_conv)(struct hibvt_lsadc *info);
> +};
> +
> +static int hibvt_lsadc_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct hibvt_lsadc *info = iio_priv(indio_dev);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + mutex_lock(&indio_dev->mlock);
> +
> + reinit_completion(&info->completion);
> +
> + /* select the channel to be used */
> + info->cur_chn = chan->channel;
> +
> + if (info->data->start_conv)
> + info->data->start_conv(info);
> +
> + if (!wait_for_completion_timeout(&info->completion,
> + HIBVT_LSADC_TIMEOUT)) {
> + if (info->data->stop_conv)
> + info->data->stop_conv(info);
> + mutex_unlock(&indio_dev->mlock);
> + return -ETIMEDOUT;
> + }
> +
> + *val = info->value;
> + mutex_unlock(&indio_dev->mlock);
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + *val = g_hibvt_lsadc_voltage[chan->channel];
> + *val2 = info->data->num_bits;
> + return IIO_VAL_FRACTIONAL_LOG2;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static irqreturn_t hibvt_lsadc_isr(int irq, void *dev_id)
> +{
> + struct hibvt_lsadc *info = (struct hibvt_lsadc *)dev_id;
> + int mask;
> +
> + mask = readl(info->regs + HIBVT_LSADC_INTSTATUS);
> + if ((mask & HIBVT_LSADC_CHN_MASK) == 0)
> + return IRQ_NONE;
> +
> + /* clear irq */
> + mask &= HIBVT_LSADC_CHN_MASK;
> + if (info->data->clear_irq)
> + info->data->clear_irq(info, mask);
> +
> + /* read value */
> + info->value = readl(info->regs +
> + HIBVT_LSADC_CHNDATA + (info->cur_chn << 2));
> + info->value &= GENMASK(info->data->num_bits - 1, 0);
> +
> + /* A single cycle of continuous mode capture is used for polled
Please keep to the standard kernel multiline comment syntax. That is:
/*
* A single cycle...
*/
See https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting
for more info.
> + * operation. This stops continuous mode after the cycle is complete.
> + */
> + if (info->data->stop_conv)
> + info->data->stop_conv(info);
> +
> + complete(&info->completion);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static const struct iio_info hibvt_lsadc_iio_info = {
> + .read_raw = hibvt_lsadc_read_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +#define HIBVT_LSADC_CHANNEL(_index, _id) { \
> + .type = IIO_VOLTAGE, \
> + .indexed = 1, \
> + .channel = _index, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_SCALE), \
> + .datasheet_name = _id, \
> +}
> +
> +static const struct iio_chan_spec hibvt_lsadc_iio_channels[] = {
> + HIBVT_LSADC_CHANNEL(0, "adc0"),
> + HIBVT_LSADC_CHANNEL(1, "adc1"),
> + HIBVT_LSADC_CHANNEL(2, "adc2"),
> +};
> +
> +static void hibvt_lsadc_clear_irq(struct hibvt_lsadc *info, int mask)
> +{
> + writel(mask, info->regs + HIBVT_LSADC_INTCLR);
> +}
> +
> +static void hibvt_lsadc_start_conv(struct hibvt_lsadc *info)
> +{
> + unsigned int con;
> +
> + /* set sample precision */
> + con = GENMASK(info->data->num_bits - 1, 0);
> + writel(con, (info->regs + HIBVT_LSADC_ACTBIT));
> +
> + /* config */
> + con = readl(info->regs + HIBVT_LSADC_CONFIG);
> + con &= ~HIBVT_CONFIG_RESET;
> + con |= (HIBVT_CONFIG_POWERDOWN | HIBVT_CONFIG_DEGLITCH |
> + HIBVT_CONFIG_MODE);
> + con &= ~(HIBVT_CONFIG_CHNA | HIBVT_CONFIG_CHNB | HIBVT_CONFIG_CHNC);
> + con |= (HIBVT_CONFIG_CHNA << info->cur_chn);
> + writel(con, (info->regs + HIBVT_LSADC_CONFIG));
> +
> + /* set timescan */
> + writel(HIBVT_LSADC_TSCAN_MS, (info->regs + HIBVT_LSADC_TIMESCAN));
Please drop the unecessary brackets from all of these calls
writel(HIBVT_LSADC_TSCAN_MS, info->regs + HIBVT_LSADC_TIMESCAN);
They don't add an clarity and will get picked up on by the various
static analysers leading to follow up patches.
> +
> + /* clear interrupt */
> + writel(HIBVT_LSADC_CHN_MASK, info->regs + HIBVT_LSADC_INTCLR);
> +
> + /* enable interrupt */
> + writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_INTEN));
> +
> + /* start scan */
> + writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_START));
> +}
> +
> +static void hibvt_lsadc_stop_conv(struct hibvt_lsadc *info)
> +{
> + /* restore timescan*/
> + writel(HIBVT_LSADC_CON_DEN, (info->regs + HIBVT_LSADC_TIMESCAN));
> +
> + /* disable interrupt */
> + writel(HIBVT_LSADC_CON_DEN, (info->regs + HIBVT_LSADC_INTEN));
> +
> + /* stop scan */
> + writel(HIBVT_LSADC_CON_EN, (info->regs + HIBVT_LSADC_STOP));
> +}
> +
> +static const struct hibvt_lsadc_data hibvt_lsadc_data = {
> + .num_bits = HIBVT_LSADC_NUM_BITS,
> + .channels = hibvt_lsadc_iio_channels,
> + .num_channels = ARRAY_SIZE(hibvt_lsadc_iio_channels),
> +
> + .clear_irq = hibvt_lsadc_clear_irq,
> + .start_conv = hibvt_lsadc_start_conv,
> + .stop_conv = hibvt_lsadc_stop_conv,
> +};
> +
> +static const struct of_device_id hibvt_lsadc_match[] = {
> + {
> + .compatible = "hisilicon,hi3516cv300-lsadc",
> + .data = &hibvt_lsadc_data,
> + },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, hibvt_lsadc_match);
> +
> +/* reset LSADC controller */
> +static void hibvt_lsadc_reset_controller(struct reset_control *reset)
> +{
> + reset_control_assert(reset);
> + usleep_range(10, 20);
> + reset_control_deassert(reset);
> +}
> +
> +static int hibvt_lsadc_probe(struct platform_device *pdev)
> +{
> + struct hibvt_lsadc *info = NULL;
> + struct device_node *np = pdev->dev.of_node;
> + struct iio_dev *indio_dev = NULL;
> + struct resource *mem;
> + const struct of_device_id *match;
> + int ret;
> + int irq;
> +
> + if (!np)
> + return -ENODEV;
> +
> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
> + if (!indio_dev) {
> + dev_err(&pdev->dev, "failed allocating iio device\n");
> + return -ENOMEM;
> + }
> + info = iio_priv(indio_dev);
> +
> + match = of_match_device(hibvt_lsadc_match, &pdev->dev);
> + info->data = match->data;
> +
> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + info->regs = devm_ioremap_resource(&pdev->dev, mem);
> + if (IS_ERR(info->regs))
> + return PTR_ERR(info->regs);
> +
> + /*
> + * The reset should be an optional property, as it should work
> + * with old devicetrees as well
> + */
> + info->reset = devm_reset_control_get(&pdev->dev, "lsadc-crg");
> + if (IS_ERR(info->reset)) {
> + ret = PTR_ERR(info->reset);
> + if (ret != -ENOENT)
> + return ret;
> +
> + dev_dbg(&pdev->dev, "no reset control found\n");
> + info->reset = NULL;
> + }
> +
> + init_completion(&info->completion);
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + dev_err(&pdev->dev, "no irq resource?\n");
> + return irq;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, irq, hibvt_lsadc_isr,
> + 0, dev_name(&pdev->dev), info);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed requesting irq %d\n", irq);
> + return ret;
> + }
> +
> + if (info->reset)
> + hibvt_lsadc_reset_controller(info->reset);
> +
> + platform_set_drvdata(pdev, indio_dev);
> +
> + indio_dev->name = dev_name(&pdev->dev);
> + indio_dev->dev.parent = &pdev->dev;
> + indio_dev->dev.of_node = pdev->dev.of_node;
> + indio_dev->info = &hibvt_lsadc_iio_info;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + indio_dev->channels = info->data->channels;
> + indio_dev->num_channels = info->data->num_channels;
> +
> + ret = devm_iio_device_register(&pdev->dev, indio_dev);
> + if (ret < 0)
> + dev_err(&pdev->dev, "failed register iio device\n");
> +
> + return ret;
> +}
> +
> +static struct platform_driver hibvt_lsadc_driver = {
> + .probe = hibvt_lsadc_probe,
> + .driver = {
> + .name = "hibvt-lsadc",
> + .of_match_table = hibvt_lsadc_match,
> + },
> +};
> +
> +module_platform_driver(hibvt_lsadc_driver);
> +
> +MODULE_AUTHOR("Allen Liu <liurenzhong@hisilicon.com>");
> +MODULE_DESCRIPTION("hisilicon BVT LSADC driver");
> +MODULE_LICENSE("GPL v2");
>
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