drivers/hwmon: Add tempsensor hwmon driver for Starfive VIC7100

drivers/hwmon/Kconfig

@@ -1924,6 +1924,14 @@ config SENSORS_TMP513
 	  This driver can also be built as a module. If so, the module
 	  will be called tmp513.
 
+config SENSORS_SFCTMP
+	tristate "SFC temperature sensor and compatible"
+	help
+	  If you say yes here you get support for SFC tmperature sensor.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called sfc_temp.
+
 config SENSORS_VEXPRESS
 	tristate "Versatile Express"
 	depends on VEXPRESS_CONFIG

drivers/hwmon/Makefile

@@ -199,6 +199,7 @@ obj-$(CONFIG_SENSORS_W83L786NG)	+= w83l786ng.o
 obj-$(CONFIG_SENSORS_WM831X)	+= wm831x-hwmon.o
 obj-$(CONFIG_SENSORS_WM8350)	+= wm8350-hwmon.o
 obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
+obj-$(CONFIG_SENSORS_SFCTMP)	+= sfctmp.o
 
 obj-$(CONFIG_SENSORS_OCC)	+= occ/
 obj-$(CONFIG_PMBUS)		+= pmbus/

drivers/hwmon/hwmon.c

@@ -855,7 +855,7 @@ EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
  */
 struct device *hwmon_device_register(struct device *dev)
 {
-	dev_warn(dev,
+	dev_dbg(dev,
 		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
 
 	return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);

drivers/hwmon/sfctmp.c

@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2021 samin.guo <samin.guo@starfivetech.com>
+ *
+ * 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/init.h>
+#include <linux/slab.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <asm-generic/io.h>
+#include <linux/regmap.h>
+
+typedef union
+{
+	uint32_t v;
+	struct {
+		uint32_t rstn   : 1; /* TempSensor reset.The RSTN can be de-asserted once the analog core has powered up. Trst(min 100ns)                                0: reset    1: de-assert */
+		uint32_t pd     : 1; /* TempSensor analog core power down.the analog core will be power up when PD de-asserted after Tpu(min 50us) has elapsed. the RSTN should be held low until the analog core is powered up.                                0:power up     1: power down */
+		uint32_t run    : 1; /* TempSensor start conversion enable
+								0:disable    1:enable */
+		uint32_t rsvd_0 : 1;
+		uint32_t cal    : 1; /* TempSensor calibration mode enable
+								0:disable    1:enable */
+		uint32_t sgn    : 1; /* TempSensor signature enable,generate a toggle value outputting on DOUT for test purposes.
+								0:disable    1:enable */
+		uint32_t rsvd_1 : 6;
+		uint32_t tm     : 4; /* TempSensor test access control
+								0000:normal     0001:Test 1  0010:Test 2  0011:Test 3
+								0100:Test4      1000:Test 8  1001:Test 9 */
+		uint32_t dout   : 12; /* TempSensor conversion value output
+								Temp(c)=DOUT/4094*Y-K */
+		uint32_t rsvd_2 : 3;
+		uint32_t digo   : 1;  /* TempSensor digital test output */
+	} bits;
+} sfc_temp_sensor_reg_t;
+
+static uint32_t s_temp_sensor_dout;
+
+struct sfc_temp{
+	const char *name;
+	void __iomem *regs;
+	int irq;
+	int clk;
+};
+
+static ssize_t sfctmp_get_temp(struct device *dev, struct device_attribute *devattr,char *buf)
+{
+	long temp,temp_z,temp_x;
+	const long Y100 = 23750, K100 = 8110,Z100 = 409400;
+
+	temp  = ((long)s_temp_sensor_dout*100)*Y100/Z100-K100;
+	temp_z = temp/100;
+	temp_x = temp%100;
+	return	sprintf(buf, "%ld.%ld\n", temp_z,temp_x);
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, sfctmp_get_temp, NULL, 0);
+
+static ssize_t sfctmp_temp_show(void)
+{
+	char buf[10];
+	sfctmp_get_temp(NULL, NULL, buf);
+	printk("temp(c): %s",buf);
+	return 0;
+}
+
+static irqreturn_t sfc_temp_isr(int irq, void *priv)
+{
+	struct sfc_temp *sfc_temp = (struct sfc_temp *)priv;
+	sfc_temp_sensor_reg_t reg;
+
+	reg.v = readl(sfc_temp->regs);
+	s_temp_sensor_dout = reg.bits.dout;
+	return IRQ_HANDLED;
+}
+
+static void temp_sensor_power_up(struct sfc_temp *sfc_temp)
+{
+	sfc_temp_sensor_reg_t init;
+	init.v = 0;
+	init.bits.pd = 1;
+	writel(init.v, sfc_temp->regs);
+	udelay(1);
+
+	init.bits.pd = 0;
+	writel(init.v, sfc_temp->regs);
+	// wait t_pu(50us) + t_rst(100ns)
+	udelay(60);
+
+	init.bits.rstn = 1;
+	writel(init.v, sfc_temp->regs);
+	// wait t_su(500ps)
+	udelay(1);
+
+	init.bits.run = 1;
+	writel(init.v, sfc_temp->regs);
+	// wait 1st sample (8192 temp_sense clk: ~2MHz)
+	mdelay(10);
+}
+
+static void temp_sensor_power_down(struct sfc_temp *sfc_temp)
+{
+	sfc_temp_sensor_reg_t init;
+
+	init.v = readl(sfc_temp->regs);
+	init.bits.run = 0;
+	writel(init.v, sfc_temp->regs);
+	udelay(1);
+
+	init.bits.pd   = 1;
+	init.bits.rstn = 0;
+	writel(init.v, sfc_temp->regs);
+	udelay(1);
+}
+
+int temp_sensor_deinit(struct sfc_temp *sfc_temp)
+{
+	temp_sensor_power_down(sfc_temp);
+	return 0;
+}
+
+static int sfc_temp_probe(struct platform_device *pdev)
+{
+	struct device *temp_dev = &pdev->dev;
+	struct device *hwmon_dev;
+	struct resource *mem;
+	struct sfc_temp *sfc_temp;
+	int ret;
+
+	dev_info(temp_dev,"probe\n");
+	sfc_temp = devm_kzalloc(&pdev->dev, sizeof(*sfc_temp), GFP_KERNEL);
+	if (!sfc_temp)
+		return -ENOMEM;
+
+	temp_dev->driver_data = (void *)sfc_temp;
+
+	sfc_temp->irq = platform_get_irq(pdev, 0);
+	if (sfc_temp->irq < 0)
+		return sfc_temp->irq;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	sfc_temp->regs = devm_ioremap_resource(temp_dev, mem);
+	if(IS_ERR(sfc_temp->regs)){
+		return PTR_ERR(sfc_temp->regs);
+	}
+
+	sfc_temp->name = "sfc_tempsnsor";
+
+	ret = devm_request_irq(temp_dev, sfc_temp->irq, sfc_temp_isr,
+			       IRQF_SHARED, sfc_temp->name, sfc_temp);
+	if(ret){
+		printk("request_irq failed.\n");
+		return ret;
+	}
+
+	temp_sensor_power_up(sfc_temp);
+	sfctmp_temp_show();
+
+	ret = device_create_file(temp_dev, &sensor_dev_attr_temp1_input.dev_attr);
+	if (ret){
+		return ret;
+	}
+	hwmon_device_register(temp_dev);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static int sfc_temp_remove(struct platform_device *pdev)
+{
+	struct device *tmp_dev = &pdev->dev;
+	struct sfc_temp *sfc_temp = (struct sfc_temp *)tmp_dev->driver_data;
+	hwmon_device_unregister(tmp_dev);
+	temp_sensor_deinit(sfc_temp);
+	return 0;
+}
+
+static const struct of_device_id sfc_temp_of_match[] = {
+	{ .compatible = "sfc,tempsensor" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, sfc_temp_of_match);
+
+static struct platform_driver sfc_temp_sensor_driver = {
+	.driver = {
+		.name	= "sfc_temp_sensor",
+		.of_match_table = of_match_ptr(sfc_temp_of_match),
+	},
+	.probe		= sfc_temp_probe,
+	.remove		= sfc_temp_remove,
+};
+module_platform_driver(sfc_temp_sensor_driver);
+
+MODULE_AUTHOR("samin.guo");
+MODULE_DESCRIPTION("SFC temperature sensor driver");
+MODULE_LICENSE("GPL");