diff options
Diffstat (limited to 'drivers/thermal')
| -rw-r--r-- | drivers/thermal/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/thermal/Makefile | 1 | ||||
| -rw-r--r-- | drivers/thermal/rcar_gen3_thermal.c | 335 |
3 files changed, 345 insertions, 0 deletions
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index c2c056cc7ea5..3912d24a07b1 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -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 diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 6a3d7b573036..adcf3cc90859 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -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 diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c new file mode 100644 index 000000000000..d33c845244b1 --- /dev/null +++ b/drivers/thermal/rcar_gen3_thermal.c @@ -0,0 +1,335 @@ +/* + * 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>"); |