From 7548666e6fc3c16a52171689035f181474c45117 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Tue, 27 Aug 2019 03:44:15 +0000 Subject: hwmon: Add Synaptics AS370 PVT sensor driver Add a new driver for Synaptics AS370 PVT sensors. Currently, only temperature is supported. Signed-off-by: Jisheng Zhang Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20190827113259.4fb64a17@xhacker.debian Signed-off-by: Guenter Roeck --- drivers/hwmon/as370-hwmon.c | 147 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) create mode 100644 drivers/hwmon/as370-hwmon.c (limited to 'drivers/hwmon/as370-hwmon.c') diff --git a/drivers/hwmon/as370-hwmon.c b/drivers/hwmon/as370-hwmon.c new file mode 100644 index 000000000000..554f03b91bfe --- /dev/null +++ b/drivers/hwmon/as370-hwmon.c @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Synaptics AS370 SoC Hardware Monitoring Driver + * + * Copyright (C) 2018 Synaptics Incorporated + * Author: Jisheng Zhang + */ + +#include +#include +#include +#include +#include +#include + +#define CTRL 0x0 +#define PD BIT(0) +#define EN BIT(1) +#define T_SEL BIT(2) +#define V_SEL BIT(3) +#define NMOS_SEL BIT(8) +#define PMOS_SEL BIT(9) +#define STS 0x4 +#define BN_MASK GENMASK(11, 0) +#define EOC BIT(12) + +struct as370_hwmon { + void __iomem *base; +}; + +static void init_pvt(struct as370_hwmon *hwmon) +{ + u32 val; + void __iomem *addr = hwmon->base + CTRL; + + val = PD; + writel_relaxed(val, addr); + val |= T_SEL; + writel_relaxed(val, addr); + val |= EN; + writel_relaxed(val, addr); + val &= ~PD; + writel_relaxed(val, addr); +} + +static int as370_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *temp) +{ + int val; + struct as370_hwmon *hwmon = dev_get_drvdata(dev); + + switch (attr) { + case hwmon_temp_input: + val = readl_relaxed(hwmon->base + STS) & BN_MASK; + *temp = DIV_ROUND_CLOSEST(val * 251802, 4096) - 85525; + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static umode_t +as370_hwmon_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 u32 as370_hwmon_temp_config[] = { + HWMON_T_INPUT, + 0 +}; + +static const struct hwmon_channel_info as370_hwmon_temp = { + .type = hwmon_temp, + .config = as370_hwmon_temp_config, +}; + +static const struct hwmon_channel_info *as370_hwmon_info[] = { + &as370_hwmon_temp, + NULL +}; + +static const struct hwmon_ops as370_hwmon_ops = { + .is_visible = as370_hwmon_is_visible, + .read = as370_hwmon_read, +}; + +static const struct hwmon_chip_info as370_chip_info = { + .ops = &as370_hwmon_ops, + .info = as370_hwmon_info, +}; + +static int as370_hwmon_probe(struct platform_device *pdev) +{ + struct resource *res; + struct device *hwmon_dev; + struct as370_hwmon *hwmon; + struct device *dev = &pdev->dev; + + hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL); + if (!hwmon) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hwmon->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hwmon->base)) + return PTR_ERR(hwmon->base); + + init_pvt(hwmon); + + hwmon_dev = devm_hwmon_device_register_with_info(dev, + "as370", + hwmon, + &as370_chip_info, + NULL); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct of_device_id as370_hwmon_match[] = { + { .compatible = "syna,as370-hwmon" }, + {}, +}; +MODULE_DEVICE_TABLE(of, as370_hwmon_match); + +static struct platform_driver as370_hwmon_driver = { + .probe = as370_hwmon_probe, + .driver = { + .name = "as370-hwmon", + .of_match_table = as370_hwmon_match, + }, +}; +module_platform_driver(as370_hwmon_driver); + +MODULE_AUTHOR("Jisheng Zhang"); +MODULE_DESCRIPTION("Synaptics AS370 SoC hardware monitor"); +MODULE_LICENSE("GPL v2"); -- cgit