---
Regards,
Ruslan.
Fabmicro, LLC.
On 2022-04-28 01:23, Jernej Škrabec wrote:
> Hi Ruslan!
>
> Dne sreda, 27. april 2022 ob 21:25:12 CEST je Ruslan Zalata napisal(a):
>> Some Allwinner SoCs like A13, A20 or T2 are equipped with two-channel
>> low rate (6 bit) ADC that is often used for extra keys. There's a
>> driver
>> for that already implementing standard input device, but it has these
>> limitations: 1) it cannot be used for general ADC data equisition, and
>> 2) it uses only one LRADC channel of two available.
>>
>> This driver provides basic hwmon interface to both channels of LRADC
>> on
>> such Allwinner SoCs.
>>
>> Signed-off-by: Ruslan Zalata <rz@xxxxxxxxxxx>
>
> Before even going to check actual driver, please read
> https://www.kernel.org/
> doc/html/latest/process/submitting-patches.html in detail.
>
> Just few basic things to fix first:
> 1. subject doesn't conform to rules
> 2. send patch to maintainers and mailing lists (use
> scripts/get_maintainer.pl)
> 3. code has style issues (multiple empty lines). Run
> scripts/checkpatch.pl --
> strict on your patch before submission and fix all reported issues.
> 4. you sent same patch two times. If it's same, it should be marked
> with
> RESEND, if not, it should be versioned (V2, V3, etc.) with short
> changelog
> after --- line (as explained in above link)
> 5. it's customary to add new entry in MAINTAINERS when adding new
> driver
>
> Best regards,
> Jernej
>
>> ---
>>
>> drivers/hwmon/Kconfig | 13 ++
>> drivers/hwmon/Makefile | 1 +
>> drivers/hwmon/sun4i-lradc-hwmon.c | 278
>>
>> ++++++++++++++++++++++++++++++
>>
>> 3 files changed, 292 insertions(+)
>> create mode 100644 drivers/hwmon/sun4i-lradc-hwmon.c
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index 68a8a27ab3b..b7732a9e992 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -521,6 +521,19 @@ config I8K
>>
>> Say Y if you intend to run userspace programs that use this
>
> interface.
>
>> Say N otherwise.
>>
>> +config SENSORS_SUN4I_LRADC
>> + tristate "Allwinner A13/A20 LRADC hwmon"
>> + depends on ARCH_SUNXI && (!KEYBOARD_SUN4I_LRADC)
>> + help
>> + Say y here to support the LRADC found in Allwinner A13/A20 SoCs.
>> + Both channels are supported.
>> +
>> + This driver can also be built as module. If so, the module
>> + will be called sun4i-lradc-hwmon.
>> +
>> + This option is not compatible with KEYBOARD_SUN4I_LRADC, one
>> + of these should be used at a time.
>> +
>>
>> config SENSORS_DA9052_ADC
>>
>> tristate "Dialog DA9052/DA9053 ADC"
>> depends on PMIC_DA9052
>>
>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>> index 8a03289e2aa..43bed6fff27 100644
>> --- a/drivers/hwmon/Makefile
>> +++ b/drivers/hwmon/Makefile
>> @@ -30,6 +30,7 @@ obj-$(CONFIG_SENSORS_AD7314) += ad7314.o
>>
>> obj-$(CONFIG_SENSORS_AD7414) += ad7414.o
>> obj-$(CONFIG_SENSORS_AD7418) += ad7418.o
>> obj-$(CONFIG_SENSORS_ADC128D818) += adc128d818.o
>>
>> +obj-$(CONFIG_SENSORS_SUN4I_LRADC) += sun4i-lradc-hwmon.o
>>
>> obj-$(CONFIG_SENSORS_ADCXX) += adcxx.o
>> obj-$(CONFIG_SENSORS_ADM1021) += adm1021.o
>> obj-$(CONFIG_SENSORS_ADM1025) += adm1025.o
>>
>> diff --git a/drivers/hwmon/sun4i-lradc-hwmon.c
>> b/drivers/hwmon/sun4i-lradc-hwmon.c new file mode 100644
>> index 00000000000..1947b716dbf
>> --- /dev/null
>> +++ b/drivers/hwmon/sun4i-lradc-hwmon.c
>> @@ -0,0 +1,278 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Allwinner sun4i (A13/A20) LRADC hwmon driver
>> + *
>> + * Copyright (C) 2022 Fabmicro, LLC., Tyumen, Russia.
>> + * Copyright (C) 2022 Ruslan Zalata <rz@xxxxxxxxxxx>
>> + */
>> +
>> +#include <linux/err.h>
>> +#include <linux/init.h>
>> +#include <linux/input.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/slab.h>
>> +#include <linux/hwmon.h>
>> +#include <linux/hwmon-sysfs.h>
>> +
>> +#define LRADC_CTRL 0x00
>> +#define LRADC_INTC 0x04
>> +#define LRADC_INTS 0x08
>> +#define LRADC_DATA0 0x0c
>> +#define LRADC_DATA1 0x10
>> +
>> +/* LRADC_CTRL bits */
>> +#define FIRST_CONVERT_DLY(x) ((x) << 24) /* 8 bits */
>> +#define CHAN_SELECT(x) ((x) << 22) /* 2 bits */
>> +#define CONTINUE_TIME_SEL(x) ((x) << 16) /* 4 bits */
>> +#define KEY_MODE_SEL(x) ((x) << 12) /* 2 bits */
>> +#define LEVELA_B_CNT(x) ((x) << 8) /* 4 bits */
>> +#define HOLD_KEY_EN(x) ((x) << 7)
>> +#define HOLD_EN(x) ((x) << 6)
>> +#define LEVELB_VOL(x) ((x) << 4) /* 2 bits */
>> +#define SAMPLE_RATE(x) ((x) << 2) /* 2 bits */
>> +#define ENABLE(x) ((x) << 0)
>> +
>> +/* LRADC_INTC and LRADC_INTS bits */
>> +#define CHAN1_KEYUP_IRQ BIT(12)
>> +#define CHAN1_ALRDY_HOLD_IRQ BIT(11)
>> +#define CHAN1_HOLD_IRQ BIT(10)
>> +#define CHAN1_KEYDOWN_IRQ BIT(9)
>> +#define CHAN1_DATA_IRQ BIT(8)
>> +#define CHAN0_KEYUP_IRQ BIT(4)
>> +#define CHAN0_ALRDY_HOLD_IRQ BIT(3)
>> +#define CHAN0_HOLD_IRQ BIT(2)
>> +#define CHAN0_KEYDOWN_IRQ BIT(1)
>> +#define CHAN0_DATA_IRQ BIT(0)
>> +
>> +
>> +struct lradc_variant {
>> + u32 bits;
>> + u32 resolution;
>> + u32 vref;
>> +};
>> +
>> +struct lradc_variant variant_sun4i_a10_lradc = {
>> + .bits = 0x3f,
>> + .resolution = 63,
>> + .vref = 2000000,
>> +};
>> +
>> +struct lradc_variant variant_sun8i_a83t_r_lradc = {
>> + .bits = 0x3f,
>> + .resolution = 63,
>> + .vref = 2000000,
>> +};
>> +
>> +static const struct of_device_id sun4i_lradc_of_match[];
>> +
>> +
>> +struct sun4i_lradc_data {
>> + struct device *dev;
>> + struct device *hwmon_dev;
>> + void __iomem *base;
>> + const struct lradc_variant *variant;
>> + u32 in[2];
>> + u32 in_mvolts[2];
>> +};
>> +
>> +
>> +static ssize_t lradc_in_mvolts_show(struct device *dev,
>> + struct device_attribute *attr, char *buf)
>> +{
>> + struct sun4i_lradc_data *data = dev_get_drvdata(dev);
>> + int nr = to_sensor_dev_attr_2(attr)->nr;
>> +
>> + if (IS_ERR(data))
>> + return PTR_ERR(data);
>> +
>> + return sprintf(buf, "%d\n", data->in_mvolts[nr]);
>> +}
>> +
>> +static ssize_t lradc_in_show(struct device *dev,
>> + struct device_attribute *attr, char *buf)
>> +{
>> + struct sun4i_lradc_data *data = dev_get_drvdata(dev);
>> + int nr = to_sensor_dev_attr_2(attr)->nr;
>> +
>> + if (IS_ERR(data))
>> + return PTR_ERR(data);
>> +
>> + return sprintf(buf, "%d\n", data->in[nr]);
>> +}
>> +
>> +
>> +static umode_t lradc_is_visible(struct kobject *kobj,
>> + struct attribute *attr, int index)
>> +{
>> + return attr->mode;
>> +}
>> +
>> +
>> +
>> +static SENSOR_DEVICE_ATTR_2_RO(in0_input, lradc_in, 0, 0);
>> +static SENSOR_DEVICE_ATTR_2_RO(in0_input_mvolts, lradc_in_mvolts, 0,
>> 1);
>> +
>> +static SENSOR_DEVICE_ATTR_2_RO(in1_input, lradc_in, 1, 0);
>> +static SENSOR_DEVICE_ATTR_2_RO(in1_input_mvolts, lradc_in_mvolts, 1,
>> 1);
>> +
>> +static struct attribute *lradc_attrs[] = {
>> + &sensor_dev_attr_in0_input.dev_attr.attr,
>> + &sensor_dev_attr_in0_input_mvolts.dev_attr.attr,
>> + &sensor_dev_attr_in1_input.dev_attr.attr,
>> + &sensor_dev_attr_in1_input_mvolts.dev_attr.attr,
>> + NULL
>> +};
>> +
>> +static const struct attribute_group lradc_group = {
>> + .attrs = lradc_attrs,
>> + .is_visible = lradc_is_visible,
>> +};
>> +__ATTRIBUTE_GROUPS(lradc);
>> +
>> +
>> +static irqreturn_t sun4i_lradc_irq(int irq, void *dev_id)
>> +{
>> + struct sun4i_lradc_data *lradc = dev_id;
>> + u32 ints;
>> +
>> + ints = readl(lradc->base + LRADC_INTS);
>> +
>> + if (ints & CHAN0_DATA_IRQ) {
>> + lradc->in[0] = readl(lradc->base + LRADC_DATA0) &
>> + lradc->variant->bits;
>> + lradc->in_mvolts[0] = lradc->in[0] * lradc->variant-
>> vref /
>> + lradc->variant->resolution / 1000;
>> + }
>> +
>> + if (ints & CHAN1_DATA_IRQ) {
>> + lradc->in[1] = readl(lradc->base + LRADC_DATA1) &
>> + lradc->variant->bits;
>> + lradc->in_mvolts[1] = lradc->in[1] * lradc->variant-
>> vref /
>> + lradc->variant->resolution / 1000;
>> + }
>> +
>> + writel(ints, lradc->base + LRADC_INTS);
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static int sun4i_lradc_open(struct device *dev)
>> +{
>> + struct sun4i_lradc_data *lradc = dev_get_drvdata(dev);
>> +
>> + writel(FIRST_CONVERT_DLY(2) | CHAN_SELECT(3) | LEVELA_B_CNT(1) |
>> + HOLD_EN(1) | KEY_MODE_SEL(2) | SAMPLE_RATE(3) |
>
> ENABLE(1),
>
>> + lradc->base + LRADC_CTRL);
>> +
>> + writel(CHAN0_DATA_IRQ | CHAN1_DATA_IRQ, lradc->base + LRADC_INTC);
>> +
>> + return 0;
>> +}
>> +
>> +static void sun4i_lradc_close(struct device *dev)
>> +{
>> + struct sun4i_lradc_data *lradc = dev_get_drvdata(dev);
>> +
>> + writel(FIRST_CONVERT_DLY(2) | LEVELA_B_CNT(1) | HOLD_EN(1) |
>> + SAMPLE_RATE(2), lradc->base + LRADC_CTRL);
>> + writel(0, lradc->base + LRADC_INTC);
>> +}
>> +
>> +static int sun4i_lradc_resume(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> +
>> + return sun4i_lradc_open(dev);
>> +}
>> +
>> +static int sun4i_lradc_suspend(struct platform_device *pdev,
>> pm_message_t
>> state) +{
>> + struct device *dev = &pdev->dev;
>> +
>> + sun4i_lradc_close(dev);
>> + return 0;
>> +}
>> +
>> +static int sun4i_lradc_remove(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> +
>> + sun4i_lradc_close(dev);
>> + return 0;
>> +}
>> +
>> +static int sun4i_lradc_probe(struct platform_device *pdev)
>> +{
>> + struct sun4i_lradc_data *lradc;
>> + struct device *dev = &pdev->dev;
>> + int error;
>> +
>> + lradc = devm_kzalloc(dev, sizeof(struct sun4i_lradc_data),
>
> GFP_KERNEL);
>
>> + if (!lradc)
>> + return -ENOMEM;
>> +
>> + dev_set_drvdata(dev, lradc);
>> +
>> + lradc->variant = of_device_get_match_data(&pdev->dev);
>> + if (!lradc->variant) {
>> + dev_err(&pdev->dev, "Missing '%s' or '%s' variant\n",
>> + sun4i_lradc_of_match[0].compatible,
>> + sun4i_lradc_of_match[1].compatible);
>> + return -EINVAL;
>> + }
>> +
>> + lradc->dev = dev;
>> + lradc->hwmon_dev = devm_hwmon_device_register_with_groups(dev,
>
> "lradc",
>
>> +
>
> lradc, lradc_groups);
>
>> + if (IS_ERR(lradc->hwmon_dev)) {
>> + error = PTR_ERR(lradc->hwmon_dev);
>> + return error;
>> + }
>> +
>> + lradc->base = devm_ioremap_resource(dev,
>> + platform_get_resource(pdev, IORESOURCE_MEM,
>
> 0));
>
>> + if (IS_ERR(lradc->base))
>> + return PTR_ERR(lradc->base);
>> +
>> + error = devm_request_irq(dev, platform_get_irq(pdev, 0),
>> + sun4i_lradc_irq, 0, "sun4i-lradc-hwmon",
>
> lradc);
>
>> + if (error)
>> + return error;
>> +
>> + error = sun4i_lradc_open(dev);
>> + if (error)
>> + return error;
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id sun4i_lradc_of_match[] = {
>> + { .compatible = "allwinner,sun4i-a10-lradc-keys", .data =
>> &variant_sun4i_a10_lradc}, + { .compatible =
>> "allwinner,sun8i-a83t-r-lradc", .data = &variant_sun8i_a83t_r_lradc},
>> +
>
> {
>
>> /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, sun4i_lradc_of_match);
>> +
>> +static struct platform_driver sun4i_lradc_driver = {
>> + .driver = {
>> + .name = "sun4i-lradc-hwmon",
>> + .of_match_table = of_match_ptr(sun4i_lradc_of_match),
>> + },
>> + .probe = sun4i_lradc_probe,
>> + .remove = sun4i_lradc_remove,
>> + .resume = sun4i_lradc_resume,
>> + .suspend = sun4i_lradc_suspend,
>> +};
>> +
>> +module_platform_driver(sun4i_lradc_driver);
>> +
>> +
>> +
>> +
>> +MODULE_DESCRIPTION("Allwinner A13/A20 LRADC hwmon driver");
>> +MODULE_AUTHOR("Ruslan Zalata <rz@xxxxxxxxxxx>");
>> +MODULE_LICENSE("GPL");
