thermal: rcar_gen3_thermal: Add R-Car Gen3 thermal driver (564e73d2) · Commits · 戴 / test

drivers/thermal/Kconfig

+9 −0

Original line number	Diff line number	Diff line
		@@ -245,6 +245,15 @@ config RCAR_THERMAL
		Enable this to plug the R-Car thermal sensor driver into the Linux
		thermal framework.

		config RCAR_GEN3_THERMAL
		tristate "Renesas R-Car Gen3 thermal driver"
		depends on ARCH_RENESAS \|\| COMPILE_TEST
		depends on HAS_IOMEM
		depends on OF
		help
		Enable this to plug the R-Car Gen3 thermal sensor driver into the Linux
		thermal framework.

		config KIRKWOOD_THERMAL
		tristate "Temperature sensor on Marvell Kirkwood SoCs"
		depends on MACH_KIRKWOOD \|\| COMPILE_TEST

drivers/thermal/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -31,6 +31,7 @@ obj-$(CONFIG_QCOM_SPMI_TEMP_ALARM) += qcom-spmi-temp-alarm.o
		obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
		obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o
		obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o
		obj-$(CONFIG_RCAR_GEN3_THERMAL) += rcar_gen3_thermal.o
		obj-$(CONFIG_KIRKWOOD_THERMAL) += kirkwood_thermal.o
		obj-y += samsung/
		obj-$(CONFIG_DOVE_THERMAL) += dove_thermal.o

drivers/thermal/rcar_gen3_thermal.c

0 → 100644

+335 −0

Original line number	Diff line number	Diff line
		/*
		* R-Car Gen3 THS thermal sensor driver
		* Based on rcar_thermal.c and work from Hien Dang and Khiem Nguyen.
		*
		* Copyright (C) 2016 Renesas Electronics Corporation.
		* Copyright (C) 2016 Sang Engineering
		*
		* 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; version 2 of the License.
		*
		* 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/delay.h>
		#include <linux/err.h>
		#include <linux/interrupt.h>
		#include <linux/io.h>
		#include <linux/module.h>
		#include <linux/mutex.h>
		#include <linux/of_device.h>
		#include <linux/platform_device.h>
		#include <linux/pm_runtime.h>
		#include <linux/thermal.h>

		/* Register offsets */
		#define REG_GEN3_IRQSTR 0x04
		#define REG_GEN3_IRQMSK 0x08
		#define REG_GEN3_IRQCTL 0x0C
		#define REG_GEN3_IRQEN 0x10
		#define REG_GEN3_IRQTEMP1 0x14
		#define REG_GEN3_IRQTEMP2 0x18
		#define REG_GEN3_IRQTEMP3 0x1C
		#define REG_GEN3_CTSR 0x20
		#define REG_GEN3_THCTR 0x20
		#define REG_GEN3_TEMP 0x28
		#define REG_GEN3_THCODE1 0x50
		#define REG_GEN3_THCODE2 0x54
		#define REG_GEN3_THCODE3 0x58

		/* CTSR bits */
		#define CTSR_PONM BIT(8)
		#define CTSR_AOUT BIT(7)
		#define CTSR_THBGR BIT(5)
		#define CTSR_VMEN BIT(4)
		#define CTSR_VMST BIT(1)
		#define CTSR_THSST BIT(0)

		/* THCTR bits */
		#define THCTR_PONM BIT(6)
		#define THCTR_THSST BIT(0)

		#define CTEMP_MASK 0xFFF

		#define MCELSIUS(temp) ((temp) * 1000)
		#define GEN3_FUSE_MASK 0xFFF

		#define TSC_MAX_NUM 3

		/* Structure for thermal temperature calculation */
		struct equation_coefs {
		int a1;
		int b1;
		int a2;
		int b2;
		};

		struct rcar_gen3_thermal_tsc {
		void __iomem *base;
		struct thermal_zone_device *zone;
		struct equation_coefs coef;
		struct mutex lock;
		};

		struct rcar_gen3_thermal_priv {
		struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM];
		};

		struct rcar_gen3_thermal_data {
		void (thermal_init)(struct rcar_gen3_thermal_tsc tsc);
		};

		static inline u32 rcar_gen3_thermal_read(struct rcar_gen3_thermal_tsc *tsc,
		u32 reg)
		{
		return ioread32(tsc->base + reg);
		}

		static inline void rcar_gen3_thermal_write(struct rcar_gen3_thermal_tsc *tsc,
		u32 reg, u32 data)
		{
		iowrite32(data, tsc->base + reg);
		}

		/*
		* Linear approximation for temperature
		*
		* [reg] = [temp] * a + b => [temp] = ([reg] - b) / a
		*
		* The constants a and b are calculated using two triplets of int values PTAT
		* and THCODE. PTAT and THCODE can either be read from hardware or use hard
		* coded values from driver. The formula to calculate a and b are taken from
		* BSP and sparsely documented and understood.
		*
		* Examining the linear formula and the formula used to calculate constants a
		* and b while knowing that the span for PTAT and THCODE values are between
		* 0x000 and 0xfff the largest integer possible is 0xfff * 0xfff == 0xffe001.
		* Integer also needs to be signed so that leaves 7 bits for binary
		* fixed point scaling.
		*/

		#define FIXPT_SHIFT 7
		#define FIXPT_INT(_x) ((_x) << FIXPT_SHIFT)
		#define FIXPT_DIV(_a, _b) DIV_ROUND_CLOSEST(((_a) << FIXPT_SHIFT), (_b))
		#define FIXPT_TO_MCELSIUS(_x) ((_x) * 1000 >> FIXPT_SHIFT)

		#define RCAR3_THERMAL_GRAN 500 /* mili Celsius */

		/* no idea where these constants come from */
		#define TJ_1 96
		#define TJ_3 -41

		static void rcar_gen3_thermal_calc_coefs(struct equation_coefs *coef,
		int ptat, int thcode)
		{
		int tj_2;

		/* TODO: Find documentation and document constant calculation formula */

		/*
		* Division is not scaled in BSP and if scaled it might overflow
		* the dividend (4095 * 4095 << 14 > INT_MAX) so keep it unscaled
		*/
		tj_2 = (FIXPT_INT((ptat[1] - ptat[2]) * 137)
		/ (ptat[0] - ptat[2])) - FIXPT_INT(41);

		coef->a1 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[2]),
		tj_2 - FIXPT_INT(TJ_3));
		coef->b1 = FIXPT_INT(thcode[2]) - coef->a1 * TJ_3;

		coef->a2 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[0]),
		tj_2 - FIXPT_INT(TJ_1));
		coef->b2 = FIXPT_INT(thcode[0]) - coef->a2 * TJ_1;
		}

		static int rcar_gen3_thermal_round(int temp)
		{
		int result, round_offs;

		round_offs = temp >= 0 ? RCAR3_THERMAL_GRAN / 2 :
		-RCAR3_THERMAL_GRAN / 2;
		result = (temp + round_offs) / RCAR3_THERMAL_GRAN;
		return result * RCAR3_THERMAL_GRAN;
		}

		static int rcar_gen3_thermal_get_temp(void devdata, int temp)
		{
		struct rcar_gen3_thermal_tsc *tsc = devdata;
		int mcelsius, val1, val2;
		u32 reg;

		/* Read register and convert to mili Celsius */
		mutex_lock(&tsc->lock);

		reg = rcar_gen3_thermal_read(tsc, REG_GEN3_TEMP) & CTEMP_MASK;

		val1 = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b1, tsc->coef.a1);
		val2 = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b2, tsc->coef.a2);
		mcelsius = FIXPT_TO_MCELSIUS((val1 + val2) / 2);

		mutex_unlock(&tsc->lock);

		/* Make sure we are inside specifications */
		if ((mcelsius < MCELSIUS(-40)) \|\| (mcelsius > MCELSIUS(125)))
		return -EIO;

		/* Round value to device granularity setting */
		*temp = rcar_gen3_thermal_round(mcelsius);

		return 0;
		}

		static struct thermal_zone_of_device_ops rcar_gen3_tz_of_ops = {
		.get_temp = rcar_gen3_thermal_get_temp,
		};

		static void r8a7795_thermal_init(struct rcar_gen3_thermal_tsc *tsc)
		{
		rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, CTSR_THBGR);
		rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, 0x0);

		usleep_range(1000, 2000);

		rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR, CTSR_PONM);
		rcar_gen3_thermal_write(tsc, REG_GEN3_IRQCTL, 0x3F);
		rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR,
		CTSR_PONM \| CTSR_AOUT \| CTSR_THBGR \| CTSR_VMEN);

		usleep_range(100, 200);

		rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR,
		CTSR_PONM \| CTSR_AOUT \| CTSR_THBGR \| CTSR_VMEN \|
		CTSR_VMST \| CTSR_THSST);

		usleep_range(1000, 2000);
		}

		static void r8a7796_thermal_init(struct rcar_gen3_thermal_tsc *tsc)
		{
		u32 reg_val;

		reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR);
		reg_val &= ~THCTR_PONM;
		rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val);

		usleep_range(1000, 2000);

		rcar_gen3_thermal_write(tsc, REG_GEN3_IRQCTL, 0x3F);
		reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR);
		reg_val \|= THCTR_THSST;
		rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val);
		}

		static const struct rcar_gen3_thermal_data r8a7795_data = {
		.thermal_init = r8a7795_thermal_init,
		};

		static const struct rcar_gen3_thermal_data r8a7796_data = {
		.thermal_init = r8a7796_thermal_init,
		};

		static const struct of_device_id rcar_gen3_thermal_dt_ids[] = {
		{ .compatible = "renesas,r8a7795-thermal", .data = &r8a7795_data},
		{ .compatible = "renesas,r8a7796-thermal", .data = &r8a7796_data},
		{},
		};
		MODULE_DEVICE_TABLE(of, rcar_gen3_thermal_dt_ids);

		static int rcar_gen3_thermal_remove(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;

		pm_runtime_put(dev);
		pm_runtime_disable(dev);

		return 0;
		}

		static int rcar_gen3_thermal_probe(struct platform_device *pdev)
		{
		struct rcar_gen3_thermal_priv *priv;
		struct device *dev = &pdev->dev;
		struct resource *res;
		struct thermal_zone_device *zone;
		int ret, i;
		const struct rcar_gen3_thermal_data *match_data =
		of_device_get_match_data(dev);

		/* default values if FUSEs are missing */
		/* TODO: Read values from hardware on supported platforms */
		int ptat[3] = { 2351, 1509, 435 };
		int thcode[TSC_MAX_NUM][3] = {
		{ 3248, 2800, 2221 },
		{ 3245, 2795, 2216 },
		{ 3250, 2805, 2237 },
		};

		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
		if (!priv)
		return -ENOMEM;

		platform_set_drvdata(pdev, priv);

		pm_runtime_enable(dev);
		pm_runtime_get_sync(dev);

		for (i = 0; i < TSC_MAX_NUM; i++) {
		struct rcar_gen3_thermal_tsc *tsc;

		tsc = devm_kzalloc(dev, sizeof(*tsc), GFP_KERNEL);
		if (!tsc) {
		ret = -ENOMEM;
		goto error_unregister;
		}

		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
		if (!res)
		break;

		tsc->base = devm_ioremap_resource(dev, res);
		if (IS_ERR(tsc->base)) {
		ret = PTR_ERR(tsc->base);
		goto error_unregister;
		}

		priv->tscs[i] = tsc;
		mutex_init(&tsc->lock);

		match_data->thermal_init(tsc);
		rcar_gen3_thermal_calc_coefs(&tsc->coef, ptat, thcode[i]);

		zone = devm_thermal_zone_of_sensor_register(dev, i, tsc,
		&rcar_gen3_tz_of_ops);
		if (IS_ERR(zone)) {
		dev_err(dev, "Can't register thermal zone\n");
		ret = PTR_ERR(zone);
		goto error_unregister;
		}
		tsc->zone = zone;
		}

		return 0;

		error_unregister:
		rcar_gen3_thermal_remove(pdev);

		return ret;
		}

		static struct platform_driver rcar_gen3_thermal_driver = {
		.driver = {
		.name = "rcar_gen3_thermal",
		.of_match_table = rcar_gen3_thermal_dt_ids,
		},
		.probe = rcar_gen3_thermal_probe,
		.remove = rcar_gen3_thermal_remove,
		};
		module_platform_driver(rcar_gen3_thermal_driver);

		MODULE_LICENSE("GPL v2");
		MODULE_DESCRIPTION("R-Car Gen3 THS thermal sensor driver");
		MODULE_AUTHOR("Wolfram Sang <wsa+renesas@sang-engineering.com>");

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