[PATCH 3/3] hwmon: sparx5: Add Sparx5 SoC temperature driver

From: Lars Povlsen
Date: Wed May 13 2020 - 09:41:58 EST


This patch adds a temperature sensor driver to the Sparx5 SoC.

Reviewed-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Signed-off-by: Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx>
---
drivers/hwmon/Kconfig | 10 +++
drivers/hwmon/Makefile | 2 +-
drivers/hwmon/sparx5-temp.c | 154 ++++++++++++++++++++++++++++++++++++
3 files changed, 165 insertions(+), 1 deletion(-)
create mode 100644 drivers/hwmon/sparx5-temp.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 4c62f900bf7e8..130cb1f1748ff 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -480,6 +480,16 @@ config SENSORS_I5K_AMB
This driver can also be built as a module. If so, the module
will be called i5k_amb.

+config SENSORS_SPARX5
+ tristate "Sparx5 SoC temperature sensor"
+ depends on ARCH_SPARX5
+ help
+ If you say yes here you get support for temperature monitoring
+ with the Microchip Sparx5 SoC.
+
+ This driver can also be built as a module. If so, the module
+ will be called sparx5-temp.
+
config SENSORS_F71805F
tristate "Fintek F71805F/FG, F71806F/FG and F71872F/FG"
depends on !PPC
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index b0b9c8e571762..28a09986b7a62 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -64,6 +64,7 @@ obj-$(CONFIG_SENSORS_DS1621) += ds1621.o
obj-$(CONFIG_SENSORS_EMC1403) += emc1403.o
obj-$(CONFIG_SENSORS_EMC2103) += emc2103.o
obj-$(CONFIG_SENSORS_EMC6W201) += emc6w201.o
+obj-$(CONFIG_SENSORS_SPARX5) += sparx5-temp.o
obj-$(CONFIG_SENSORS_F71805F) += f71805f.o
obj-$(CONFIG_SENSORS_F71882FG) += f71882fg.o
obj-$(CONFIG_SENSORS_F75375S) += f75375s.o
@@ -190,4 +191,3 @@ obj-$(CONFIG_SENSORS_OCC) += occ/
obj-$(CONFIG_PMBUS) += pmbus/

ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
-
diff --git a/drivers/hwmon/sparx5-temp.c b/drivers/hwmon/sparx5-temp.c
new file mode 100644
index 0000000000000..bf9dd102a9825
--- /dev/null
+++ b/drivers/hwmon/sparx5-temp.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Sparx5 SoC temperature sensor driver
+ *
+ * Copyright (C) 2020 Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx>
+ */
+
+#include <linux/bitops.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+#define TEMP_CTRL 0
+#define TEMP_CFG 4
+#define TEMP_CFG_CYCLES GENMASK(24, 15)
+#define TEMP_CFG_CYCLES_OFF 15
+#define TEMP_CFG_ENA BIT(0)
+#define TEMP_STAT 8
+#define TEMP_STAT_VALID BIT(12)
+#define TEMP_STAT_TEMP GENMASK(11, 0)
+
+struct s5_hwmon {
+ void __iomem *base;
+};
+
+static void s5_temp_enable(struct s5_hwmon *hwmon)
+{
+ u32 val = readl(hwmon->base + TEMP_CFG);
+ u32 clk = 250;
+
+ val &= ~TEMP_CFG_CYCLES;
+ val |= (clk << TEMP_CFG_CYCLES_OFF);
+ val |= TEMP_CFG_ENA;
+
+ writel(val, hwmon->base + TEMP_CFG);
+}
+
+static void s5_temp_disable(void *data)
+{
+ struct s5_hwmon *hwmon = data;
+ u32 val = readl(hwmon->base + TEMP_CFG);
+
+ val &= ~TEMP_CFG_ENA;
+
+ writel(val, hwmon->base + TEMP_CFG);
+}
+
+static int s5_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *temp)
+{
+ struct s5_hwmon *hwmon = dev_get_drvdata(dev);
+ int rc = 0, value;
+ u32 stat;
+
+ switch (attr) {
+ case hwmon_temp_input:
+ stat = readl_relaxed(hwmon->base + TEMP_STAT);
+ if (stat & TEMP_STAT_VALID) {
+ value = (stat & TEMP_STAT_TEMP);
+ value = DIV_ROUND_CLOSEST(value * 3522, 4096) - 1094;
+ value *= 100;
+ *temp = value;
+ } else
+ rc = -EINVAL;
+ break;
+ default:
+ rc = -EOPNOTSUPP;
+ }
+
+ return rc;
+}
+
+static umode_t s5_is_visible(const void *_data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ if (type != hwmon_temp)
+ return 0;
+
+ switch (attr) {
+ case hwmon_temp_input:
+ return 0444;
+ default:
+ return 0;
+ }
+}
+
+static const struct hwmon_channel_info *s5_info[] = {
+ HWMON_CHANNEL_INFO(chip,
+ HWMON_C_REGISTER_TZ),
+ HWMON_CHANNEL_INFO(temp,
+ HWMON_T_INPUT),
+ NULL
+};
+
+static const struct hwmon_ops s5_hwmon_ops = {
+ .is_visible = s5_is_visible,
+ .read = s5_read,
+};
+
+static const struct hwmon_chip_info s5_chip_info = {
+ .ops = &s5_hwmon_ops,
+ .info = s5_info,
+};
+
+static int s5_temp_probe(struct platform_device *pdev)
+{
+ struct device *hwmon_dev;
+ struct s5_hwmon *hwmon;
+ int err = 0;
+
+ hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL);
+ if (!hwmon)
+ return -ENOMEM;
+
+ hwmon->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(hwmon->base))
+ return PTR_ERR(hwmon->base);
+
+ err = devm_add_action(&pdev->dev, s5_temp_disable, hwmon);
+ if (err)
+ return err;
+
+ s5_temp_enable(hwmon);
+
+ hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
+ "s5_temp",
+ hwmon,
+ &s5_chip_info,
+ NULL);
+
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+const struct of_device_id s5_temp_match[] = {
+ { .compatible = "microchip,sparx5-temp" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, s5_temp_match);
+
+static struct platform_driver s5_temp_driver = {
+ .probe = s5_temp_probe,
+ .driver = {
+ .name = "sparx5-temp",
+ .of_match_table = s5_temp_match,
+ },
+};
+
+module_platform_driver(s5_temp_driver);
+
+MODULE_AUTHOR("Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Sparx5 SoC temperature sensor driver");
+MODULE_LICENSE("GPL");
--
2.26.2