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");
