| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Broadcom STB AVS TMON thermal sensor driver |
| * |
| * Copyright (c) 2015-2017 Broadcom |
| */ |
| |
| #define DRV_NAME "brcmstb_thermal" |
| |
| #define pr_fmt(fmt) DRV_NAME ": " fmt |
| |
| #include <linux/bitops.h> |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <linux/io.h> |
| #include <linux/irqreturn.h> |
| #include <linux/interrupt.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/of_device.h> |
| #include <linux/thermal.h> |
| |
| #define AVS_TMON_STATUS 0x00 |
| #define AVS_TMON_STATUS_valid_msk BIT(11) |
| #define AVS_TMON_STATUS_data_msk GENMASK(10, 1) |
| #define AVS_TMON_STATUS_data_shift 1 |
| |
| #define AVS_TMON_EN_OVERTEMP_RESET 0x04 |
| #define AVS_TMON_EN_OVERTEMP_RESET_msk BIT(0) |
| |
| #define AVS_TMON_RESET_THRESH 0x08 |
| #define AVS_TMON_RESET_THRESH_msk GENMASK(10, 1) |
| #define AVS_TMON_RESET_THRESH_shift 1 |
| |
| #define AVS_TMON_INT_IDLE_TIME 0x10 |
| |
| #define AVS_TMON_EN_TEMP_INT_SRCS 0x14 |
| #define AVS_TMON_EN_TEMP_INT_SRCS_high BIT(1) |
| #define AVS_TMON_EN_TEMP_INT_SRCS_low BIT(0) |
| |
| #define AVS_TMON_INT_THRESH 0x18 |
| #define AVS_TMON_INT_THRESH_high_msk GENMASK(26, 17) |
| #define AVS_TMON_INT_THRESH_high_shift 17 |
| #define AVS_TMON_INT_THRESH_low_msk GENMASK(10, 1) |
| #define AVS_TMON_INT_THRESH_low_shift 1 |
| |
| #define AVS_TMON_TEMP_INT_CODE 0x1c |
| #define AVS_TMON_TP_TEST_ENABLE 0x20 |
| |
| /* Default coefficients */ |
| #define AVS_TMON_TEMP_SLOPE 487 |
| #define AVS_TMON_TEMP_OFFSET 410040 |
| |
| /* HW related temperature constants */ |
| #define AVS_TMON_TEMP_MAX 0x3ff |
| #define AVS_TMON_TEMP_MIN -88161 |
| #define AVS_TMON_TEMP_MASK AVS_TMON_TEMP_MAX |
| |
| enum avs_tmon_trip_type { |
| TMON_TRIP_TYPE_LOW = 0, |
| TMON_TRIP_TYPE_HIGH, |
| TMON_TRIP_TYPE_RESET, |
| TMON_TRIP_TYPE_MAX, |
| }; |
| |
| struct avs_tmon_trip { |
| /* HW bit to enable the trip */ |
| u32 enable_offs; |
| u32 enable_mask; |
| |
| /* HW field to read the trip temperature */ |
| u32 reg_offs; |
| u32 reg_msk; |
| int reg_shift; |
| }; |
| |
| static struct avs_tmon_trip avs_tmon_trips[] = { |
| /* Trips when temperature is below threshold */ |
| [TMON_TRIP_TYPE_LOW] = { |
| .enable_offs = AVS_TMON_EN_TEMP_INT_SRCS, |
| .enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_low, |
| .reg_offs = AVS_TMON_INT_THRESH, |
| .reg_msk = AVS_TMON_INT_THRESH_low_msk, |
| .reg_shift = AVS_TMON_INT_THRESH_low_shift, |
| }, |
| /* Trips when temperature is above threshold */ |
| [TMON_TRIP_TYPE_HIGH] = { |
| .enable_offs = AVS_TMON_EN_TEMP_INT_SRCS, |
| .enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_high, |
| .reg_offs = AVS_TMON_INT_THRESH, |
| .reg_msk = AVS_TMON_INT_THRESH_high_msk, |
| .reg_shift = AVS_TMON_INT_THRESH_high_shift, |
| }, |
| /* Automatically resets chip when above threshold */ |
| [TMON_TRIP_TYPE_RESET] = { |
| .enable_offs = AVS_TMON_EN_OVERTEMP_RESET, |
| .enable_mask = AVS_TMON_EN_OVERTEMP_RESET_msk, |
| .reg_offs = AVS_TMON_RESET_THRESH, |
| .reg_msk = AVS_TMON_RESET_THRESH_msk, |
| .reg_shift = AVS_TMON_RESET_THRESH_shift, |
| }, |
| }; |
| |
| struct brcmstb_thermal_priv { |
| void __iomem *tmon_base; |
| struct device *dev; |
| struct thermal_zone_device *thermal; |
| }; |
| |
| /* Convert a HW code to a temperature reading (millidegree celsius) */ |
| static inline int avs_tmon_code_to_temp(struct thermal_zone_device *tz, |
| u32 code) |
| { |
| return (AVS_TMON_TEMP_OFFSET - |
| (int)((code & AVS_TMON_TEMP_MAX) * AVS_TMON_TEMP_SLOPE)); |
| } |
| |
| /* |
| * Convert a temperature value (millidegree celsius) to a HW code |
| * |
| * @temp: temperature to convert |
| * @low: if true, round toward the low side |
| */ |
| static inline u32 avs_tmon_temp_to_code(struct thermal_zone_device *tz, |
| int temp, bool low) |
| { |
| if (temp < AVS_TMON_TEMP_MIN) |
| return AVS_TMON_TEMP_MAX; /* Maximum code value */ |
| |
| if (temp >= AVS_TMON_TEMP_OFFSET) |
| return 0; /* Minimum code value */ |
| |
| if (low) |
| return (u32)(DIV_ROUND_UP(AVS_TMON_TEMP_OFFSET - temp, |
| AVS_TMON_TEMP_SLOPE)); |
| else |
| return (u32)((AVS_TMON_TEMP_OFFSET - temp) / |
| AVS_TMON_TEMP_SLOPE); |
| } |
| |
| static int brcmstb_get_temp(void *data, int *temp) |
| { |
| struct brcmstb_thermal_priv *priv = data; |
| u32 val; |
| long t; |
| |
| val = __raw_readl(priv->tmon_base + AVS_TMON_STATUS); |
| |
| if (!(val & AVS_TMON_STATUS_valid_msk)) { |
| dev_err(priv->dev, "reading not valid\n"); |
| return -EIO; |
| } |
| |
| val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift; |
| |
| t = avs_tmon_code_to_temp(priv->thermal, val); |
| if (t < 0) |
| *temp = 0; |
| else |
| *temp = t; |
| |
| return 0; |
| } |
| |
| static void avs_tmon_trip_enable(struct brcmstb_thermal_priv *priv, |
| enum avs_tmon_trip_type type, int en) |
| { |
| struct avs_tmon_trip *trip = &avs_tmon_trips[type]; |
| u32 val = __raw_readl(priv->tmon_base + trip->enable_offs); |
| |
| dev_dbg(priv->dev, "%sable trip, type %d\n", en ? "en" : "dis", type); |
| |
| if (en) |
| val |= trip->enable_mask; |
| else |
| val &= ~trip->enable_mask; |
| |
| __raw_writel(val, priv->tmon_base + trip->enable_offs); |
| } |
| |
| static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv, |
| enum avs_tmon_trip_type type) |
| { |
| struct avs_tmon_trip *trip = &avs_tmon_trips[type]; |
| u32 val = __raw_readl(priv->tmon_base + trip->reg_offs); |
| |
| val &= trip->reg_msk; |
| val >>= trip->reg_shift; |
| |
| return avs_tmon_code_to_temp(priv->thermal, val); |
| } |
| |
| static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv, |
| enum avs_tmon_trip_type type, |
| int temp) |
| { |
| struct avs_tmon_trip *trip = &avs_tmon_trips[type]; |
| u32 val, orig; |
| |
| dev_dbg(priv->dev, "set temp %d to %d\n", type, temp); |
| |
| /* round toward low temp for the low interrupt */ |
| val = avs_tmon_temp_to_code(priv->thermal, temp, |
| type == TMON_TRIP_TYPE_LOW); |
| |
| val <<= trip->reg_shift; |
| val &= trip->reg_msk; |
| |
| orig = __raw_readl(priv->tmon_base + trip->reg_offs); |
| orig &= ~trip->reg_msk; |
| orig |= val; |
| __raw_writel(orig, priv->tmon_base + trip->reg_offs); |
| } |
| |
| static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv) |
| { |
| u32 val; |
| |
| val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE); |
| return avs_tmon_code_to_temp(priv->thermal, val); |
| } |
| |
| static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data) |
| { |
| struct brcmstb_thermal_priv *priv = data; |
| int low, high, intr; |
| |
| low = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_LOW); |
| high = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_HIGH); |
| intr = avs_tmon_get_intr_temp(priv); |
| |
| dev_dbg(priv->dev, "low/intr/high: %d/%d/%d\n", |
| low, intr, high); |
| |
| /* Disable high-temp until next threshold shift */ |
| if (intr >= high) |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0); |
| /* Disable low-temp until next threshold shift */ |
| if (intr <= low) |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0); |
| |
| /* |
| * Notify using the interrupt temperature, in case the temperature |
| * changes before it can next be read out |
| */ |
| thermal_zone_device_update(priv->thermal, intr); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int brcmstb_set_trips(void *data, int low, int high) |
| { |
| struct brcmstb_thermal_priv *priv = data; |
| |
| dev_dbg(priv->dev, "set trips %d <--> %d\n", low, high); |
| |
| /* |
| * Disable low-temp if "low" is too small. As per thermal framework |
| * API, we use -INT_MAX rather than INT_MIN. |
| */ |
| if (low <= -INT_MAX) { |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0); |
| } else { |
| avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_LOW, low); |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 1); |
| } |
| |
| /* Disable high-temp if "high" is too big. */ |
| if (high == INT_MAX) { |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0); |
| } else { |
| avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_HIGH, high); |
| avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 1); |
| } |
| |
| return 0; |
| } |
| |
| static const struct thermal_zone_of_device_ops of_ops = { |
| .get_temp = brcmstb_get_temp, |
| .set_trips = brcmstb_set_trips, |
| }; |
| |
| static const struct of_device_id brcmstb_thermal_id_table[] = { |
| { .compatible = "brcm,avs-tmon" }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table); |
| |
| static int brcmstb_thermal_probe(struct platform_device *pdev) |
| { |
| struct thermal_zone_device *thermal; |
| struct brcmstb_thermal_priv *priv; |
| struct resource *res; |
| int irq, ret; |
| |
| priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| priv->tmon_base = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(priv->tmon_base)) |
| return PTR_ERR(priv->tmon_base); |
| |
| priv->dev = &pdev->dev; |
| platform_set_drvdata(pdev, priv); |
| |
| thermal = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, priv, |
| &of_ops); |
| if (IS_ERR(thermal)) { |
| ret = PTR_ERR(thermal); |
| dev_err(&pdev->dev, "could not register sensor: %d\n", ret); |
| return ret; |
| } |
| |
| priv->thermal = thermal; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) { |
| dev_err(&pdev->dev, "could not get IRQ\n"); |
| return irq; |
| } |
| ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, |
| brcmstb_tmon_irq_thread, IRQF_ONESHOT, |
| DRV_NAME, priv); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "could not request IRQ: %d\n", ret); |
| return ret; |
| } |
| |
| dev_info(&pdev->dev, "registered AVS TMON of-sensor driver\n"); |
| |
| return 0; |
| } |
| |
| static struct platform_driver brcmstb_thermal_driver = { |
| .probe = brcmstb_thermal_probe, |
| .driver = { |
| .name = DRV_NAME, |
| .of_match_table = brcmstb_thermal_id_table, |
| }, |
| }; |
| module_platform_driver(brcmstb_thermal_driver); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_AUTHOR("Brian Norris"); |
| MODULE_DESCRIPTION("Broadcom STB AVS TMON thermal driver"); |