thermal: Add BCM2711 thermal driver

This adds the thermal sensor driver for the Broadcom BCM2711 SoC,
which is placed on the Raspberry Pi 4. The driver only provides
SoC temperature reading so far.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1578941778-23321-3-git-send-email-stefan.wahren@i2se.com

diff --git a/drivers/thermal/broadcom/Kconfig b/drivers/thermal/broadcom/Kconfig
index cf43e1520de9f9ca921cf5e5f9b9824888991383..061f1db6edc9e7b35aa57d38e385d2197d8bad64 100644 (file)
--- a/drivers/thermal/broadcom/Kconfig
+++ b/drivers/thermal/broadcom/Kconfig
@@ -1,4 +1,11 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config BCM2711_THERMAL
+       tristate "Broadcom AVS RO thermal sensor driver"
+       depends on ARCH_BCM2835 || COMPILE_TEST
+       depends on THERMAL_OF && MFD_SYSCON
+       help
+         Support for thermal sensors on Broadcom BCM2711 SoCs.
+
 config BCM2835_THERMAL
        tristate "Thermal sensors on bcm2835 SoC"
        depends on ARCH_BCM2835 || COMPILE_TEST

diff --git a/drivers/thermal/broadcom/Makefile b/drivers/thermal/broadcom/Makefile
index 490ab1f7a86df837e2967058ccc809da1826d226..c917b243d5f00dbb75c41b5942a4c6433810628e 100644 (file)
--- a/drivers/thermal/broadcom/Makefile
+++ b/drivers/thermal/broadcom/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_BCM2711_THERMAL)          += bcm2711_thermal.o
 obj-$(CONFIG_BCM2835_THERMAL)          += bcm2835_thermal.o
 obj-$(CONFIG_BRCMSTB_THERMAL)          += brcmstb_thermal.o
 obj-$(CONFIG_BCM_NS_THERMAL)           += ns-thermal.o

diff --git a/drivers/thermal/broadcom/bcm2711_thermal.c b/drivers/thermal/broadcom/bcm2711_thermal.c
new file mode 100644 (file)
index 0000000..67c2a73
--- /dev/null
+++ b/drivers/thermal/broadcom/bcm2711_thermal.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Broadcom AVS RO thermal sensor driver
+ *
+ * based on brcmstb_thermal
+ *
+ * Copyright (C) 2020 Stefan Wahren
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+#include "../thermal_hwmon.h"
+
+#define AVS_RO_TEMP_STATUS             0x200
+#define AVS_RO_TEMP_STATUS_VALID_MSK   (BIT(16) | BIT(10))
+#define AVS_RO_TEMP_STATUS_DATA_MSK    GENMASK(9, 0)
+
+struct bcm2711_thermal_priv {
+       struct regmap *regmap;
+       struct thermal_zone_device *thermal;
+};
+
+static int bcm2711_get_temp(void *data, int *temp)
+{
+       struct bcm2711_thermal_priv *priv = data;
+       int slope = thermal_zone_get_slope(priv->thermal);
+       int offset = thermal_zone_get_offset(priv->thermal);
+       u32 val;
+       int ret;
+       long t;
+
+       ret = regmap_read(priv->regmap, AVS_RO_TEMP_STATUS, &val);
+       if (ret)
+               return ret;
+
+       if (!(val & AVS_RO_TEMP_STATUS_VALID_MSK))
+               return -EIO;
+
+       val &= AVS_RO_TEMP_STATUS_DATA_MSK;
+
+       /* Convert a HW code to a temperature reading (millidegree celsius) */
+       t = slope * val + offset;
+
+       *temp = t < 0 ? 0 : t;
+
+       return 0;
+}
+
+static const struct thermal_zone_of_device_ops bcm2711_thermal_of_ops = {
+       .get_temp       = bcm2711_get_temp,
+};
+
+static const struct of_device_id bcm2711_thermal_id_table[] = {
+       { .compatible = "brcm,bcm2711-thermal" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, bcm2711_thermal_id_table);
+
+static int bcm2711_thermal_probe(struct platform_device *pdev)
+{
+       struct thermal_zone_device *thermal;
+       struct bcm2711_thermal_priv *priv;
+       struct device *dev = &pdev->dev;
+       struct device_node *parent;
+       struct regmap *regmap;
+       int ret;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       /* get regmap from syscon node */
+       parent = of_get_parent(dev->of_node); /* parent should be syscon node */
+       regmap = syscon_node_to_regmap(parent);
+       of_node_put(parent);
+       if (IS_ERR(regmap)) {
+               ret = PTR_ERR(regmap);
+               dev_err(dev, "failed to get regmap: %d\n", ret);
+               return ret;
+       }
+       priv->regmap = regmap;
+
+       thermal = devm_thermal_zone_of_sensor_register(dev, 0, priv,
+                                                      &bcm2711_thermal_of_ops);
+       if (IS_ERR(thermal)) {
+               ret = PTR_ERR(thermal);
+               dev_err(dev, "could not register sensor: %d\n", ret);
+               return ret;
+       }
+
+       priv->thermal = thermal;
+
+       thermal->tzp->no_hwmon = false;
+       ret = thermal_add_hwmon_sysfs(thermal);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static struct platform_driver bcm2711_thermal_driver = {
+       .probe = bcm2711_thermal_probe,
+       .driver = {
+               .name = "bcm2711_thermal",
+               .of_match_table = bcm2711_thermal_id_table,
+       },
+};
+module_platform_driver(bcm2711_thermal_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stefan Wahren");
+MODULE_DESCRIPTION("Broadcom AVS RO thermal sensor driver");