This patch adds thermal driver for ZTE's zx2967 family. Signed-off-by: Baoyou Xie <baoyou.xie@xxxxxxxxxx> --- drivers/thermal/Kconfig | 8 ++ drivers/thermal/Makefile | 1 + drivers/thermal/zx2967_thermal.c | 265 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 274 insertions(+) create mode 100644 drivers/thermal/zx2967_thermal.c diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 18f2de6..f64bd50 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -444,4 +444,12 @@ config BCM2835_THERMAL help Support for thermal sensors on Broadcom bcm2835 SoCs. +config ZX2967_THERMAL + tristate "Thermal sensors on zx2967 SoC" + depends on ARCH_ZX || COMPILE_TEST + help + Enable the zx2967 thermal sensors driver, which supports + the primitive temperature sensor embedded in zx2967 SoCs. + This sensor generates the real time die temperature. + endif diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 677c6d9..c00c05e 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -57,3 +57,4 @@ obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o obj-$(CONFIG_MTK_THERMAL) += mtk_thermal.o obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.o obj-$(CONFIG_BCM2835_THERMAL) += bcm2835_thermal.o +obj-$(CONFIG_ZX2967_THERMAL) += zx2967_thermal.o diff --git a/drivers/thermal/zx2967_thermal.c b/drivers/thermal/zx2967_thermal.c new file mode 100644 index 0000000..d8642cf --- /dev/null +++ b/drivers/thermal/zx2967_thermal.c @@ -0,0 +1,265 @@ +/* + * ZTE's zx2967 family thermal sensor driver + * + * Copyright (C) 2017 ZTE Ltd. + * + * Author: Baoyou Xie <baoyou.xie@xxxxxxxxxx> + * + * License terms: GNU General Public License (GPL) version 2 + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/thermal.h> + +/* Power Mode: 0->low 1->high */ +#define ZX2967_THERMAL_POWER_MODE 0 + +/* DCF Control Register */ +#define ZX2967_THERMAL_DCF 0x4 + +/* Selection Register */ +#define ZX2967_THERMAL_SEL 0x8 + +/* Control Register */ +#define ZX2967_THERMAL_CTRL 0x10 + +#define ZX2967_THERMAL_READY 0x1000 +#define ZX2967_THERMAL_TEMP_MASK 0xfff +#define ZX2967_THERMAL_ID_MASK 0x18 +#define ZX2967_THERMAL_ID0 0x8 +#define ZX2967_THERMAL_ID1 0x10 + +struct zx2967_thermal_sensor { + struct zx2967_thermal_priv *priv; + struct thermal_zone_device *tzd; + int id; +}; + +#define NUM_SENSORS 1 + +struct zx2967_thermal_priv { + struct zx2967_thermal_sensor sensors[NUM_SENSORS]; + /* Prevents reads sensor in parallel */ + struct mutex lock; + struct clk *clk_gate; + struct clk *pclk; + s32 slope; + s32 offset; + void __iomem *regs; + struct device *dev; +}; + +static int zx2967_thermal_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev); + + if (priv && priv->pclk) + clk_disable_unprepare(priv->pclk); + + if (priv && priv->clk_gate) + clk_disable_unprepare(priv->clk_gate); + + return 0; +} + +static int zx2967_thermal_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev); + int error; + + error = clk_prepare_enable(priv->clk_gate); + if (error) + return error; + + error = clk_prepare_enable(priv->pclk); + if (error) { + clk_disable_unprepare(priv->clk_gate); + return error; + } + + return 0; +} + +static int zx2967_thermal_get_temp(void *data, int *temp) +{ + void __iomem *regs; + struct zx2967_thermal_sensor *sensor = data; + struct zx2967_thermal_priv *priv = sensor->priv; + unsigned long timeout = jiffies + msecs_to_jiffies(100); + u32 val, sel_id; + + regs = priv->regs; + mutex_lock(&priv->lock); + + writel_relaxed(0, regs + ZX2967_THERMAL_POWER_MODE); + writel_relaxed(2, regs + ZX2967_THERMAL_DCF); + + val = readl_relaxed(regs + ZX2967_THERMAL_SEL); + val &= ~ZX2967_THERMAL_ID_MASK; + sel_id = sensor->id ? ZX2967_THERMAL_ID0 : ZX2967_THERMAL_ID1; + val |= sel_id; + writel_relaxed(val, regs + ZX2967_THERMAL_SEL); + + usleep_range(100, 300); + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL); + while (!(val & ZX2967_THERMAL_READY)) { + if (time_after(jiffies, timeout)) { + dev_err(priv->dev, "Thermal sensor %d data timeout\n", + sensor->id); + mutex_unlock(&priv->lock); + return -ETIMEDOUT; + } + usleep_range(100, 300); + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL); + } + + writel_relaxed(3, regs + ZX2967_THERMAL_DCF); + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL) + & ZX2967_THERMAL_TEMP_MASK; + writel_relaxed(1, regs + ZX2967_THERMAL_POWER_MODE); + + /* Calculate temperature */ + *temp = DIV_ROUND_CLOSEST(((s32)val + priv->offset) * 1000, + priv->slope); + + mutex_unlock(&priv->lock); + + return 0; +} + +static struct thermal_zone_of_device_ops zx2967_of_thermal_ops = { + .get_temp = zx2967_thermal_get_temp, +}; + +static int zx2967_thermal_probe(struct platform_device *pdev) +{ + struct zx2967_thermal_priv *priv; + struct resource *res; + u32 buf[2]; + int ret, i; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->regs)) + return PTR_ERR(priv->regs); + + ret = of_property_read_u32_array(pdev->dev.of_node, + "coefficients", buf, 2); + if (ret) { + dev_err(&pdev->dev, "failed to read coefficients\n"); + return ret; + } + priv->slope = (s32)buf[0]; + priv->offset = (s32)buf[1]; + + priv->clk_gate = devm_clk_get(&pdev->dev, "gate"); + if (IS_ERR(priv->clk_gate)) { + ret = PTR_ERR(priv->clk_gate); + dev_err(&pdev->dev, "failed to get clock gate: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(priv->clk_gate); + if (ret) { + dev_err(&pdev->dev, "failed to enable converter clock: %d\n", + ret); + return ret; + } + + priv->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(priv->pclk)) { + ret = PTR_ERR(priv->pclk); + clk_disable_unprepare(priv->clk_gate); + dev_err(&pdev->dev, "failed to get apb clock: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(priv->pclk); + if (ret) { + clk_disable_unprepare(priv->clk_gate); + dev_err(&pdev->dev, "failed to enable converter clock: %d\n", + ret); + return ret; + } + + mutex_init(&priv->lock); + for (i = 0; i < NUM_SENSORS; i++) { + struct zx2967_thermal_sensor *sensor = &priv->sensors[i]; + + sensor->priv = priv; + sensor->id = i; + sensor->tzd = thermal_zone_of_sensor_register(&pdev->dev, + i, sensor, &zx2967_of_thermal_ops); + if (IS_ERR(sensor->tzd)) { + ret = PTR_ERR(sensor->tzd); + dev_err(&pdev->dev, "failed to register sensor %d: %d\n", + i, ret); + goto remove_ts; + } + } + priv->dev = &pdev->dev; + platform_set_drvdata(pdev, priv); + + return 0; + +remove_ts: + clk_disable_unprepare(priv->clk_gate); + clk_disable_unprepare(priv->pclk); + for (i--; i >= 0; i--) + thermal_zone_of_sensor_unregister(&pdev->dev, + priv->sensors[i].tzd); + + return ret; +} + +static int zx2967_thermal_exit(struct platform_device *pdev) +{ + struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < NUM_SENSORS; i++) { + struct zx2967_thermal_sensor *sensor = &priv->sensors[i]; + + thermal_zone_of_sensor_unregister(&pdev->dev, sensor->tzd); + } + clk_disable_unprepare(priv->pclk); + clk_disable_unprepare(priv->clk_gate); + + return 0; +} + +static const struct of_device_id zx2967_thermal_id_table[] = { + { .compatible = "zte,zx296718-thermal" }, + {} +}; +MODULE_DEVICE_TABLE(of, zx2967_thermal_id_table); + +static SIMPLE_DEV_PM_OPS(zx2967_thermal_pm_ops, + zx2967_thermal_suspend, zx2967_thermal_resume); + +static struct platform_driver zx2967_thermal_driver = { + .probe = zx2967_thermal_probe, + .remove = zx2967_thermal_exit, + .driver = { + .name = "zx2967_thermal", + .of_match_table = zx2967_thermal_id_table, + .pm = &zx2967_thermal_pm_ops, + }, +}; +module_platform_driver(zx2967_thermal_driver); + +MODULE_AUTHOR("Baoyou Xie <baoyou.xie@xxxxxxxxxx>"); +MODULE_DESCRIPTION("ZTE zx2967 thermal driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html