Re: [PATCH v8 3/6] thermal: mediatek: Add LVTS drivers for SoC theraml zones for mt8192

From: AngeloGioacchino Del Regno
Date: Wed Jul 27 2022 - 05:24:17 EST


Il 26/07/22 15:55, Balsam CHIHI ha scritto:
Add a LVTS (Low voltage thermal sensor) driver to report junction
temperatures in Mediatek SoC mt8192 and register the maximum temperature
of sensors and each sensor as a thermal zone.

Signed-off-by: Yu-Chia Chang <ethan.chang@xxxxxxxxxxxx>
Signed-off-by: Michael Kao <michael.kao@xxxxxxxxxxxx>
Signed-off-by: Ben Tseng <ben.tseng@xxxxxxxxxxxx>
Signed-off-by: Alexandre Bailon <abailon@xxxxxxxxxxxx>
Signed-off-by: Balsam CHIHI <bchihi@xxxxxxxxxxxx>

Hello Balsam,

there are a few comments on this patch.

First of all, can you please fix the typo that you have in the commit title?
theraml -> thermal

...then, please, the commit description:
Add a LVTS (Low Voltage Thermal Sensor) <- capitalize

and

Mediatek -> MediaTek

---
drivers/thermal/mediatek/Kconfig | 27 +
drivers/thermal/mediatek/Makefile | 2 +
drivers/thermal/mediatek/lvts_mt8192.c | 241 ++++++
drivers/thermal/mediatek/soc_temp.c | 2 +-
drivers/thermal/mediatek/soc_temp_lvts.c | 928 +++++++++++++++++++++++
drivers/thermal/mediatek/soc_temp_lvts.h | 365 +++++++++
6 files changed, 1564 insertions(+), 1 deletion(-)
create mode 100644 drivers/thermal/mediatek/lvts_mt8192.c
create mode 100644 drivers/thermal/mediatek/soc_temp_lvts.c
create mode 100644 drivers/thermal/mediatek/soc_temp_lvts.h

diff --git a/drivers/thermal/mediatek/Kconfig b/drivers/thermal/mediatek/Kconfig
index 9c41e9079fc3..7fc04237dd50 100644
--- a/drivers/thermal/mediatek/Kconfig
+++ b/drivers/thermal/mediatek/Kconfig
@@ -20,4 +20,31 @@ config MTK_SOC_THERMAL
configures thermal controllers to collect temperature
via AUXADC interface.
+config MTK_SOC_THERMAL_LVTS
+ tristate "LVTS (Low voltage thermal sensor) driver for Mediatek SoCs"
+ depends on HAS_IOMEM
+ depends on NVMEM
+ depends on RESET_TI_SYSCON
+ help
+ Enable this option if you want to get SoC temperature
+ information for MediaTek platforms. This driver
+ configures LVTS thermal controllers to collect temperatures
+ via Analog Serial Interface(ASIF).

Fix the indentation, please:

help
Enable this option.......
(\t<space><space>)



+
+endif
+
+if MTK_SOC_THERMAL_LVTS
+
+config LVTS_MT8192
+ tristate "LVTS driver for MediaTek MT8192 SoC"
+ depends on HAS_IOMEM
+ depends on NVMEM
+ depends on RESET_TI_SYSCON
+ depends on MTK_SOC_THERMAL_LVTS
+ help
+ Enable this option if you want to get SoC temperature
+ information for MT8192. This driver
+ configures LVTS thermal controllers to collect temperatures
+ via ASIF.
+
endif
diff --git a/drivers/thermal/mediatek/Makefile b/drivers/thermal/mediatek/Makefile
index 4b4cb04a358f..5ff1197e80ab 100644
--- a/drivers/thermal/mediatek/Makefile
+++ b/drivers/thermal/mediatek/Makefile
@@ -1 +1,3 @@
obj-$(CONFIG_MTK_SOC_THERMAL) += soc_temp.o
+obj-$(CONFIG_MTK_SOC_THERMAL_LVTS) += soc_temp_lvts.o
+obj-$(CONFIG_LVTS_MT8192) += lvts_mt8192.o
diff --git a/drivers/thermal/mediatek/lvts_mt8192.c b/drivers/thermal/mediatek/lvts_mt8192.c
new file mode 100644
index 000000000000..19e4e82c410b
--- /dev/null
+++ b/drivers/thermal/mediatek/lvts_mt8192.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 MediaTek Inc.
+ */
+
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include "soc_temp_lvts.h"
+
+enum mt8192_lvts_mcu_sensor_enum {
+ MT8192_TS1_0,
+ MT8192_TS1_1,
+ MT8192_TS2_0,
+ MT8192_TS2_1,
+ MT8192_TS3_0,
+ MT8192_TS3_1,
+ MT8192_TS3_2,
+ MT8192_TS3_3,
+ MT8192_NUM_TS_MCU
+};
+
+enum mt8192_lvts_ap_sensor_enum {
+ MT8192_TS4_0,
+ MT8192_TS4_1,
+ MT8192_TS5_0,
+ MT8192_TS5_1,
+ MT8192_TS6_0,
+ MT8192_TS6_1,
+ MT8192_TS7_0,
+ MT8192_TS7_1,
+ MT8192_TS7_2,
+ MT8192_NUM_TS_AP
+};
+
+static void mt8192_mcu_efuse_to_cal_data(struct lvts_data *lvts_data)
+{
+ struct lvts_sensor_cal_data *cal_data = &lvts_data->cal_data;
+ unsigned int i, j;
+ const unsigned int mt8192_TS[] = {MT8192_TS2_0, MT8192_TS3_0};


Please fix and reorder (here and for any other instance):

const unsigned int mt8192_ts[] = { MT8192_TS2_0, MT8192_TS3_0 };
struct lvts_sensor_cal_data *cal_data = &lvts_data->cal_data;
unsigned int i, j;

+
+ cal_data->golden_temp = GET_CAL_DATA_BITMASK(0, lvts_data, 31, 24);
+
+ for (i = 0; i < MT8192_NUM_TS_MCU; i++)
+ cal_data->count_r[i] = GET_CAL_DATA_BITMASK(i + 1, lvts_data, 23, 0);
+
+ cal_data->count_rc[MT8192_TS1_0] = GET_CAL_DATA_BITMASK(21, lvts_data, 23, 0);

..snip..

+
+static const struct lvts_tc_settings mt8192_tc_mcu_settings[] = {
+ [0] = {
+ .dev_id = 0x81,
+ .addr_offset = 0x0,
+ .num_sensor = 2,
+ .sensor_map = {MT8192_TS1_0, MT8192_TS1_1},

Please, leave a space after opening and before closing the braces.

+ .tc_speed = &tc_speed_mt8192,
+ .hw_filter = LVTS_FILTER_2_OF_4,
+ .dominator_sensing_point = SENSING_POINT1,
+ .hw_reboot_trip_point = HW_REBOOT_TRIP_POINT,
+ .irq_bit = BIT(3),
+ },

..snip..

+
+static const struct lvts_data mt8192_lvts_ap_data = {
+ .num_tc = (ARRAY_SIZE(mt8192_tc_ap_settings)),
+ .tc = mt8192_tc_ap_settings,
+ .num_sensor = MT8192_NUM_TS_AP,
+ .ops = {
+ .efuse_to_cal_data = mt8192_ap_efuse_to_cal_data,
+ .device_enable_and_init = lvts_device_enable_and_init_v4,
+ .device_enable_auto_rck = lvts_device_enable_auto_rck_v4,
+ .device_read_count_rc_n = lvts_device_read_count_rc_n_v4,
+ .set_cal_data = lvts_set_calibration_data_v4,
+ .init_controller = lvts_init_controller_v4,
+ },
+ .feature_bitmap = FEATURE_DEVICE_AUTO_RCK,
+ .num_efuse_addr = NUM_EFUSE_ADDR,
+ .num_efuse_block = NUM_EFUSE_BLOCK_MT8192,
+ .cal_data = {
+ .default_golden_temp = DEFAULT_GOLDEN_TEMP,
+ .default_count_r = DEFAULT_CUONT_R,
+ .default_count_rc = DEFAULT_CUONT_RC,
+ },
+ .coeff = {
+ .a = COEFF_A,
+ .b = COEFF_B,
+ },
+};
+
+static const struct of_device_id lvts_of_match[] = {

I don't like having one driver per SoC, where we have only two specific functions.

I suggest to either:
- Remove the static word from mt8192_lvts_ap_data and put the of_match
in soc_temp_lvts.c; or
- Separate the SoCs by LVTS version: create a lvts_v4.c where we group all
of the V4 SoCs (so, currently, MT8192 and MT8195): this will allow us to
eventually get a lvts_v3, lvts_v2, etc, where we group other SoCs.

I prefer the second way, as MediaTek has a lot of SoCs and I can see this list
growing a lot when these will be (hopefully) upstreamed.



+ { .compatible = "mediatek,mt8192-lvts-mcu", .data = &mt8192_lvts_mcu_data, },
+ { .compatible = "mediatek,mt8192-lvts-ap", .data = &mt8192_lvts_ap_data, },
+ {},
+};
+MODULE_DEVICE_TABLE(of, lvts_of_match);
+
+static struct platform_driver soc_temp_lvts = {
+ .probe = lvts_probe,
+ .remove = lvts_remove,
+ .suspend = lvts_suspend,
+ .resume = lvts_resume,
+ .driver = {
+ .name = "mtk-soc-temp-lvts-mt8192",
+ .of_match_table = lvts_of_match,
+ },
+};
+module_platform_driver(soc_temp_lvts);
+
+MODULE_AUTHOR("Yu-Chia Chang <ethan.chang@xxxxxxxxxxxx>");
+MODULE_AUTHOR("Michael Kao <michael.kao@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MediaTek soc temperature driver");
+MODULE_LICENSE("GPL v2");

You should run checkpatch.pl. Please.

diff --git a/drivers/thermal/mediatek/soc_temp.c b/drivers/thermal/mediatek/soc_temp.c
index ede94eadddda..60924f8f98e9 100644
--- a/drivers/thermal/mediatek/soc_temp.c
+++ b/drivers/thermal/mediatek/soc_temp.c
@@ -23,7 +23,7 @@
#include <linux/reset.h>
#include <linux/types.h>
-#include "thermal_hwmon.h"
+#include "../thermal_hwmon.h"

This change doesn't belong to this commit.

/* AUXADC Registers */
#define AUXADC_CON1_SET_V 0x008
diff --git a/drivers/thermal/mediatek/soc_temp_lvts.c b/drivers/thermal/mediatek/soc_temp_lvts.c
new file mode 100644
index 000000000000..ee7efc0de65f
--- /dev/null
+++ b/drivers/thermal/mediatek/soc_temp_lvts.c
@@ -0,0 +1,928 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 MediaTek Inc.
+ */
+
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/thermal.h>
+#include "soc_temp_lvts.h"
+
+static int lvts_raw_to_temp(struct lvts_formula_coeff *co, unsigned int msr_raw)
+{
+ /* This function returns degree mC */
+
+ int temp;
+
+ temp = (co->a * ((unsigned long long)msr_raw)) >> 14;
+ temp = temp + co->golden_temp * 500 + co->b;
+
+ return temp;
+}
+
+static unsigned int lvts_temp_to_raw(struct lvts_formula_coeff *co, int temp)
+{
+ unsigned int msr_raw;
+
+ msr_raw = div_s64((s64)((co->golden_temp * 500 + co->b - temp)) << 14,
+ (-1 * co->a));
+
+ return msr_raw;
+}
+
+static int soc_temp_lvts_read_temp(void *data, int *temperature)
+{
+ struct soc_temp_tz *lvts_tz = (struct soc_temp_tz *)data;
+ struct lvts_data *lvts_data = lvts_tz->lvts_data;
+ unsigned int msr_raw;
+
+ msr_raw = readl(lvts_data->reg[lvts_tz->id]) & MRS_RAW_MASK;
+ if (msr_raw == 0)
+ return -EINVAL;
+
+ *temperature = lvts_raw_to_temp(&lvts_data->coeff, msr_raw);
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops soc_temp_lvts_ops = {
+ .get_temp = soc_temp_lvts_read_temp,
+};
+
+static void lvts_write_device(struct lvts_data *lvts_data, unsigned int data,
+ int tc_id)
+{
+ void __iomem *base = GET_BASE_ADDR(lvts_data, tc_id);
+
+ writel(DEVICE_WRITE | data, LVTS_CONFIG_0 + base);
+
+ usleep_range(5, 15);
+}
+
+static unsigned int lvts_read_device(struct lvts_data *lvts_data,
+ unsigned int reg_idx, int tc_id)
+{
+ struct device *dev = lvts_data->dev;
+ void __iomem *base = GET_BASE_ADDR(lvts_data, tc_id);
+ unsigned int data;
+ int ret;
+
+ writel(READ_DEVICE_REG(reg_idx), LVTS_CONFIG_0 + base);
+
+ usleep_range(5, 15);
+
+ ret = readl_poll_timeout(LVTS_CONFIG_0 + base, data,
+ !(data & DEVICE_ACCESS_STARTUS), 2, 200);
+ if (ret)
+ dev_err(dev,
+ "Error: LVTS %d DEVICE_ACCESS_START is not ready\n", tc_id);
+
+ data = readl(LVTSRDATA0_0 + base);
+
+ return data;
+}
+
+static const char * const lvts_error_table[] = {"IDLE", "Write transaction",
+ "Waiting for read after Write", "Disable Continue fetching on Device",
+ "Read transaction", "Set Device special Register for Voltage threshold",
+ "Set TSMCU number for Fetch"};

In my opinion, that's unreadable.

static const char * const lvts_error_table[] = {

"Idle",

"Write transaction",

"Waiting for read after write",

"Disable continue fetching on device",

"Read transaction",

"Set device special register for voltage threshold",

"Set TSMCU number for fetch"

};

...but like this, it's way more readable.


+
+static void wait_all_tc_sensing_point_idle(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ unsigned int mask, error_code, is_error;
+ void __iomem *base;
+ int i, cnt, ret;
+
+ mask = BIT(10) | BIT(7) | BIT(0);

What are these magic bits?
Please add definitions.

+
+ for (cnt = 0; cnt < 2; cnt++) {
+ is_error = 0;
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ base = GET_BASE_ADDR(lvts_data, i);
+ ret = readl_poll_timeout(LVTSMSRCTL1_0 + base, error_code,
+ !(error_code & mask), 2, 200);
+
+ error_code = ((error_code & BIT(10)) >> 8) +
+ ((error_code & BIT(7)) >> 6) +
+ (error_code & BIT(0));
+
+ if (ret)
+ dev_err(dev, "LVTS %d error: %s\n",
+ i, lvts_error_table[error_code]);
+
+ if (error_code != 0)
+ is_error = 1;
+ }
+
+ if (is_error == 0)
+ break;
+ }
+}
+

...snip...

+static void set_hw_filter(struct lvts_data *lvts_data, int tc_id)
+{
+ struct device *dev = lvts_data->dev;
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ unsigned int option;
+ void __iomem *base;
+
+ base = GET_BASE_ADDR(lvts_data, tc_id);
+ option = tc[tc_id].hw_filter & 0x7;
+ /*
+ * hw filter
+ * 000: Get one sample
+ * 001: Get 2 samples and average them
+ * 010: Get 4 samples, drop max and min, then average the rest of 2 samples
+ * 011: Get 6 samples, drop max and min, then average the rest of 4 samples
+ * 100: Get 10 samples, drop max and min, then average the rest of 8 samples
+ * 101: Get 18 samples, drop max and min, then average the rest of 16 samples
+ */
+ option = (option << 9) | (option << 6) | (option << 3) | option;
+
+ writel(option, LVTSMSRCTL0_0 + base);
+ dev_dbg(dev, "LVTS_TC_%d, LVTSMSRCTL0_0= 0x%x\n",
+ tc_id, readl(LVTSMSRCTL0_0 + base));
+}
+
+static int get_dominator_index(struct lvts_data *lvts_data, int tc_id)
+{
+ struct device *dev = lvts_data->dev;
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ int d_index;
+
+ if (tc[tc_id].dominator_sensing_point == ALL_SENSING_POINTS) {
+ d_index = ALL_SENSING_POINTS;
+ } else if (tc[tc_id].dominator_sensing_point <
+ tc[tc_id].num_sensor){

There's no reason to break this line.

+ d_index = tc[tc_id].dominator_sensing_point;
+ } else {
+ dev_err(dev,
+ "Error: LVTS%d, dominator_sensing_point= %d should smaller than num_sensor= %d\n",

"Error:" is unneeded, as this is a dev_err, so it's definitely an error.
Also, s/should/shall be/g

+ tc_id, tc[tc_id].dominator_sensing_point,
+ tc[tc_id].num_sensor);
+
+ dev_err(dev, "Use the sensing point 0 as the dominated sensor\n");
+ d_index = SENSING_POINT0;
+ }
+
+ return d_index;
+}
+
+static void disable_hw_reboot_interrupt(struct lvts_data *lvts_data, int tc_id)
+{
+ unsigned int temp;
+ void __iomem *base;
+
+ base = GET_BASE_ADDR(lvts_data, tc_id);
+
+ /*
+ * LVTS thermal controller has two interrupts for thermal HW reboot
+ * One is for AP SW and the other is for RGU
+ * The interrupt of AP SW can turn off by a bit of a register, but
+ * the other for RGU cannot.
+ * To prevent rebooting device accidentally, we are going to add
+ * a huge offset to LVTS and make LVTS always report extremely low
+ * temperature.
+ */
+
+ /*
+ * After adding the huge offset 0x3FFF, LVTS alawys adds the

s/alawys/always/g

+ * offset to MSR_RAW.
+ * When MSR_RAW is larger, SW will convert lower temperature/
+ */
+ temp = readl(LVTSPROTCTL_0 + base);
+ writel(temp | 0x3FFF, LVTSPROTCTL_0 + base);
+
+ /* Disable the interrupt of AP SW */
+ temp = readl(LVTSMONINT_0 + base);
+ writel(temp & ~(STAGE3_INT_EN), LVTSMONINT_0 + base);
+}
+
+static void enable_hw_reboot_interrupt(struct lvts_data *lvts_data, int tc_id)
+{
+ unsigned int temp;
+ void __iomem *base;
+
+ base = GET_BASE_ADDR(lvts_data, tc_id);
+
+ /* Enable the interrupt of AP SW */
+ temp = readl(LVTSMONINT_0 + base);
+ writel(temp | STAGE3_INT_EN, LVTSMONINT_0 + base);
+ /* Clear the offset */
+ temp = readl(LVTSPROTCTL_0 + base);
+ writel(temp & ~PROTOFFSET, LVTSPROTCTL_0 + base);
+}
+
+static void set_tc_hw_reboot_threshold(struct lvts_data *lvts_data,
+ int trip_point, int tc_id)
+{
+ struct device *dev = lvts_data->dev;
+ unsigned int msr_raw, temp, config, d_index;
+ void __iomem *base;

void __iomem *base;
struct device *dev = lvts_data->dev;
unsigned int msr_raw, temp, config, d_index;

or

unsigned int msr_raw, temp, config, d_index;
struct device *dev = lvts_data->dev;
void __iomem *base;

Make it pretty - human readabilty is important.
P.S.: I prefer the first option.
P.P.S.: This is not the only instance!

+
+ base = GET_BASE_ADDR(lvts_data, tc_id);
+ d_index = get_dominator_index(lvts_data, tc_id);
+
+ dev_info(dev, "lvts_tc_%d: dominator sensing point = %d\n", tc_id, d_index);

dev_dbg().

+
+ disable_hw_reboot_interrupt(lvts_data, tc_id);
+
+ temp = readl(LVTSPROTCTL_0 + base);
+ if (d_index == ALL_SENSING_POINTS) {
+ /* Maximum of 4 sensing points */
+ config = (0x1 << 16);
+ writel(config | temp, LVTSPROTCTL_0 + base);
+ } else {
+ /* Select protection sensor */
+ config = ((d_index << 2) + 0x2) << 16;
+ writel(config | temp, LVTSPROTCTL_0 + base);
+ }
+
+ msr_raw = lvts_temp_to_raw(&lvts_data->coeff, trip_point);
+ writel(msr_raw, LVTSPROTTC_0 + base);
+
+ enable_hw_reboot_interrupt(lvts_data, tc_id);
+}
+
+static void set_all_tc_hw_reboot(struct lvts_data *lvts_data)
+{
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ int i, trip_point;
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ trip_point = tc[i].hw_reboot_trip_point;
+
+ if (tc[i].num_sensor == 0)
+ continue;
+
+ if (trip_point == THERMAL_TEMP_INVALID)
+ continue;
+
+ set_tc_hw_reboot_threshold(lvts_data, trip_point, i);
+ }
+}
+
+static int lvts_init(struct lvts_data *lvts_data)
+{
+ struct platform_ops *ops = &lvts_data->ops;
+ struct device *dev = lvts_data->dev;
+ int ret;
+
+ ret = clk_prepare_enable(lvts_data->clk);
+ if (ret) {
+ dev_err(dev,
+ "Error: Failed to enable lvts controller clock: %d\n",
+ ret);

This should be:
dev_err(dev, "Failed to enable lvts controller clock: %d\n", ret);

(or return dev_err_probe()).

+ return ret;
+ }
+
+ lvts_reset(lvts_data);
+
+ device_identification(lvts_data);
+ if (ops->device_enable_and_init)
+ ops->device_enable_and_init(lvts_data);
+
+ if (HAS_FEATURE(lvts_data, FEATURE_DEVICE_AUTO_RCK)) {
+ if (ops->device_enable_auto_rck)
+ ops->device_enable_auto_rck(lvts_data);
+ } else {
+ if (ops->device_read_count_rc_n)
+ ops->device_read_count_rc_n(lvts_data);
+ }

if (HAS_FEATURE(lvts_data, FEATURE_DEVICE_AUTO_RCK) && ops....)
ops....
else if (ops.....)
ops.....

+
+ if (ops->set_cal_data)
+ ops->set_cal_data(lvts_data);
+
+ disable_all_sensing_points(lvts_data);
+ wait_all_tc_sensing_point_idle(lvts_data);
+ if (ops->init_controller)
+ ops->init_controller(lvts_data);
+ enable_all_sensing_points(lvts_data);
+
+ set_all_tc_hw_reboot(lvts_data);
+
+ return 0;
+}
+
+static int prepare_calibration_data(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ struct lvts_sensor_cal_data *cal_data = &lvts_data->cal_data;
+ struct platform_ops *ops = &lvts_data->ops;
+ int i, offset;
+ char buffer[512];
+
+ cal_data->count_r = devm_kcalloc(dev, lvts_data->num_sensor,
+ sizeof(*cal_data->count_r), GFP_KERNEL);
+ if (!cal_data->count_r)
+ return -ENOMEM;
+
+ cal_data->count_rc = devm_kcalloc(dev, lvts_data->num_sensor,
+ sizeof(*cal_data->count_rc), GFP_KERNEL);
+ if (!cal_data->count_rc)
+ return -ENOMEM;
+
+ if (ops->efuse_to_cal_data && !cal_data->use_fake_efuse)
+ ops->efuse_to_cal_data(lvts_data);
+ if (cal_data->golden_temp == 0 || cal_data->golden_temp > GOLDEN_TEMP_MAX)
+ cal_data->use_fake_efuse = 1;
+
+ if (cal_data->use_fake_efuse) {
+ /* It means all efuse data are equal to 0 */
+ dev_err(dev,
+ "%s: This sample is not calibrated, fake !!\n", __func__);
+
+ cal_data->golden_temp = cal_data->default_golden_temp;
+ for (i = 0; i < lvts_data->num_sensor; i++) {
+ cal_data->count_r[i] = cal_data->default_count_r;
+ cal_data->count_rc[i] = cal_data->default_count_rc;
+ }
+ }
+
+ lvts_data->coeff.golden_temp = cal_data->golden_temp;
+
+ dev_dbg(dev, "golden_temp = %d\n", cal_data->golden_temp);
+
+ offset = snprintf(buffer, sizeof(buffer), "[lvts_cal] num:g_count:g_count_rc ");
+ for (i = 0; i < lvts_data->num_sensor; i++)
+ offset += snprintf(buffer + offset, sizeof(buffer) - offset, "%d:%d:%d ",
+ i, cal_data->count_r[i], cal_data->count_rc[i]);
+
+ buffer[offset] = '\0';

What is this string for?
You're formatting it but never using, what's the point?

+
+ return 0;
+}
+
+static int get_calibration_data(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ char cell_name[32];
+ struct nvmem_cell *cell;
+ u32 *buf;
+ size_t len;
+ int i, j, index = 0, ret;
+
+ lvts_data->efuse = devm_kcalloc(dev, lvts_data->num_efuse_addr,
+ sizeof(*lvts_data->efuse), GFP_KERNEL);
+ if (!lvts_data->efuse)
+ return -ENOMEM;
+
+ for (i = 0; i < lvts_data->num_efuse_block; i++) {
+ snprintf(cell_name, sizeof(cell_name), "lvts_calib_data%d", i + 1);
+ cell = nvmem_cell_get(dev, cell_name);
+ if (IS_ERR(cell)) {
+ dev_err(dev, "Error: Failed to get nvmem cell %s\n", cell_name);
+ return PTR_ERR(cell);
+ }
+
+ buf = (u32 *)nvmem_cell_read(cell, &len);
+ nvmem_cell_put(cell);
+
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ for (j = 0; j < (len / sizeof(u32)); j++) {
+ if (index >= lvts_data->num_efuse_addr) {
+ dev_err(dev, "Array efuse is going to overflow");
+ kfree(buf);
+ return -EINVAL;

If we get an error here, you should free all of the allocated buffers, which means
that you have to walk back from i to 0 and kfree everything, or this is going to be
a (relatively) big memory leak.

+ }
+
+ lvts_data->efuse[index] = buf[j];
+ index++;
+ }
+
+ kfree(buf);
+ }
+
+ ret = prepare_calibration_data(lvts_data);
+
+ return ret;
+}
+
+static int lvts_init_tc_regs(struct device *dev, struct lvts_data *lvts_data)
+{
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ unsigned int i, j, s_index;
+ void __iomem *base;
+
+ lvts_data->reg = devm_kcalloc(dev, lvts_data->num_sensor,
+ sizeof(*lvts_data->reg), GFP_KERNEL);
+ if (!lvts_data->reg)
+ return -ENOMEM;
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ base = GET_BASE_ADDR(lvts_data, i);
+ for (j = 0; j < tc[i].num_sensor; j++) {
+ s_index = tc[i].sensor_map[j];
+ lvts_data->reg[s_index] = LVTSMSR0_0 + base + 0x4 * j;
+ }
+ }
+
+ return 0;
+}
+
+static int of_update_lvts_data(struct lvts_data *lvts_data,
+ struct platform_device *pdev)
+{
+ struct device *dev = lvts_data->dev;
+ struct resource *res;
+ int ret;
+
+ lvts_data->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(lvts_data->clk))
+ return PTR_ERR(lvts_data->clk);
+
+ /* Get base address */
+ res = platform_get_mem_or_io(pdev, 0);
+ if (!res) {
+ dev_err(dev, "No IO resource\n");
+ return -ENXIO;
+ }
+
+ lvts_data->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(lvts_data->base)) {
+ dev_err(dev, "Failed to remap io\n");
+ return PTR_ERR(lvts_data->base);
+ }
+
+ /* Get interrupt number */
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0) {
+ dev_err(dev, "No irq resource\n");
+ return -EINVAL;

Why are you overriding the return value? return ret here.

+ }
+ lvts_data->irq_num = ret;
+
+ /* Get reset control */
+ lvts_data->reset = devm_reset_control_get_by_index(dev, 0);
+ if (IS_ERR(lvts_data->reset)) {
+ dev_err(dev, "Failed to get reset control\n");
+ return PTR_ERR(lvts_data->reset);
+ }
+
+ ret = lvts_init_tc_regs(dev, lvts_data);
+ if (ret)
+ return ret;
+
+ ret = get_calibration_data(lvts_data);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+

..snip..

+
+static irqreturn_t irq_handler(int irq, void *dev_id)
+{
+ struct lvts_data *lvts_data = (struct lvts_data *)dev_id;
+ struct device *dev = lvts_data->dev;
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ unsigned int i, *irq_bitmap;
+ void __iomem *base;
+
+ irq_bitmap = kcalloc(1, sizeof(*irq_bitmap), GFP_ATOMIC);
+

You're using this for debugging only? Also, why wasn't this stack-allocated?

Just remove it.

+ if (!irq_bitmap)
+ return IRQ_NONE;
+
+ base = lvts_data->base;
+ *irq_bitmap = readl(THERMINTST + base);
+ dev_dbg(dev, "THERMINTST = 0x%x\n", *irq_bitmap);
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ if (tc[i].irq_bit == 0)
+ tc_irq_handler(lvts_data, i);
+ }
+
+ kfree(irq_bitmap);
+
+ return IRQ_HANDLED;
+}
+
+static int lvts_register_irq_handler(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ int ret;
+
+ ret = devm_request_irq(dev, lvts_data->irq_num, irq_handler,
+ IRQF_TRIGGER_HIGH, "mtk_lvts", lvts_data);

Interrupt flags are specified in devicetree: why are you forcing TRIGGER_HIGH here?

+
+ if (ret) {
+ dev_err(dev, "Failed to register LVTS IRQ, ret %d, irq_num %d\n",
+ ret, lvts_data->irq_num);
+ lvts_close(lvts_data);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lvts_register_thermal_zones(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ struct thermal_zone_device *tzdev;
+ struct soc_temp_tz *lvts_tz;
+ int i, ret;
+
+ for (i = 0; i < lvts_data->num_sensor; i++) {
+ lvts_tz = devm_kzalloc(dev, sizeof(*lvts_tz), GFP_KERNEL);
+ if (!lvts_tz) {
+ lvts_close(lvts_data);
+ return -ENOMEM;
+ }
+
+ lvts_tz->id = i;
+ lvts_tz->lvts_data = lvts_data;
+
+ tzdev = devm_thermal_zone_of_sensor_register(dev, lvts_tz->id,
+ lvts_tz, &soc_temp_lvts_ops);
+
+ if (IS_ERR(tzdev)) {
+ if (lvts_tz->id != 0)
+ return 0;
+
+ ret = PTR_ERR(tzdev);
+ dev_err(dev, "Error: Failed to register lvts tz %d, ret = %d\n",

s/Error: //g - here and everywhere else: a dev_err() *is* an error print.

+ lvts_tz->id, ret);
+ lvts_close(lvts_data);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+

..snip..

+
+int lvts_device_read_count_rc_n_v4(struct lvts_data *lvts_data)
+{
+ /* Resistor-Capacitor Calibration */
+ /* count_RC_N: count RC now */
+ struct device *dev = lvts_data->dev;
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ struct lvts_sensor_cal_data *cal_data = &lvts_data->cal_data;
+ unsigned int offset, size, s_index, data;
+ void __iomem *base;
+ int ret, i, j;
+ char buffer[512];

I don't think that you need this buffer to be that long and I'm sure that its
size can be reduced.
I didn't check how much you need, but I'm guessing that you need less than a
quarter of that size.

+
+ cal_data->count_rc_now = devm_kcalloc(dev, lvts_data->num_sensor,
+ sizeof(*cal_data->count_rc_now), GFP_KERNEL);
+ if (!cal_data->count_rc_now)
+ return -ENOMEM;
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ base = GET_BASE_ADDR(lvts_data, i);
+ for (j = 0; j < tc[i].num_sensor; j++) {
+ s_index = tc[i].sensor_map[j];
+
+ lvts_write_device(lvts_data, SELECT_SENSOR_RCK_V4(j), i);
+ lvts_write_device(lvts_data, SET_DEVICE_SINGLE_MODE_V4, i);
+ usleep_range(10, 20);
+
+ lvts_write_device(lvts_data, KICK_OFF_RCK_COUNTING_V4, i);
+ usleep_range(30, 40);
+
+ ret = readl_poll_timeout(LVTS_CONFIG_0 + base, data,
+ !(data & DEVICE_SENSING_STATUS), 2, 200);
+ if (ret)
+ dev_err(dev,
+ "Error: LVTS %d DEVICE_SENSING_STATUS didn't ready\n", i);
+
+ data = lvts_read_device(lvts_data, 0x00, i);
+
+ cal_data->count_rc_now[s_index] = (data & GENMASK(23, 0));

No magic GENMASK() or BIT() please, add a definition for readability.

+ }
+
+ /* Recover Setting for Normal Access on
+ * temperature fetch
+ */
+ lvts_write_device(lvts_data, SET_SENSOR_NO_RCK_V4, i);
+ lvts_write_device(lvts_data, SET_DEVICE_LOW_POWER_SINGLE_MODE_V4, i);
+ }
+
+ size = sizeof(buffer);
+ offset = snprintf(buffer, size, "[COUNT_RC_NOW] ");
+ for (i = 0; i < lvts_data->num_sensor; i++)
+ offset += snprintf(buffer + offset, size - offset, "%d:%d ",
+ i, cal_data->count_rc_now[i]);
+
+ buffer[offset] = '\0';
+ dev_dbg(dev, "%s\n", buffer);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(lvts_device_read_count_rc_n_v4);
+
+void lvts_set_calibration_data_v4(struct lvts_data *lvts_data)
+{
+ const struct lvts_tc_settings *tc = lvts_data->tc;
+ struct lvts_sensor_cal_data *cal_data = &lvts_data->cal_data;
+ unsigned int i, j, s_index, lvts_calib_data;
+ void __iomem *base;
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ base = GET_BASE_ADDR(lvts_data, i);
+
+ for (j = 0; j < tc[i].num_sensor; j++) {
+ s_index = tc[i].sensor_map[j];
+ if (HAS_FEATURE(lvts_data, FEATURE_DEVICE_AUTO_RCK))
+ lvts_calib_data = cal_data->count_r[s_index];
+ else
+ lvts_calib_data = (((unsigned long long)

lvts_calib_data is unsigned int. You're assigning unsigned long long here.

Also, since this is register-size bound, use fixed size types.

+ cal_data->count_rc_now[s_index]) *
+ cal_data->count_r[s_index]) >> 14;
+
+ writel(lvts_calib_data, LVTSEDATA00_0 + base + 0x4 * j);
+ }
+ }
+}
+EXPORT_SYMBOL_GPL(lvts_set_calibration_data_v4);
+
+void lvts_init_controller_v4(struct lvts_data *lvts_data)
+{
+ struct device *dev = lvts_data->dev;
+ unsigned int i;
+ void __iomem *base;
+
+ for (i = 0; i < lvts_data->num_tc; i++) {
+ base = GET_BASE_ADDR(lvts_data, i);
+
+ lvts_write_device(lvts_data, SET_DEVICE_LOW_POWER_SINGLE_MODE_V4, i);
+
+ writel(SET_SENSOR_INDEX, LVTSTSSEL_0 + base);
+ writel(SET_CALC_SCALE_RULES, LVTSCALSCALE_0 + base);
+
+ set_polling_speed(lvts_data, i);
+ set_hw_filter(lvts_data, i);
+
+ dev_info(dev, "lvts_tc_%d: read all %d sensors in %d us, one in %d us\n",
+ i, GET_TC_SENSOR_NUM(lvts_data, i), GROUP_LATENCY_US(i), SENSOR_LATENCY_US(i));

dev_dbg().

+ }
+}
+EXPORT_SYMBOL_GPL(lvts_init_controller_v4);
+
+int lvts_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct lvts_data *lvts_data;
+ int ret;
+
+ lvts_data = (struct lvts_data *)of_device_get_match_data(dev);
+
+ if (!lvts_data) {
+ dev_err(dev, "Error: Failed to get lvts platform data\n");
+ return -ENODATA;
+ }
+
+ lvts_data->dev = &pdev->dev;
+
+ ret = of_update_lvts_data(lvts_data, pdev);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, lvts_data);
+
+ ret = lvts_init(lvts_data);
+ if (ret)
+ return ret;
+
+ ret = lvts_register_irq_handler(lvts_data);
+ if (ret)
+ return ret;

If anything goes wrong here, you're leaving the lvts_data->clk clock enabled.
Please fix.

+
+ ret = lvts_register_thermal_zones(lvts_data);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+int lvts_remove(struct platform_device *pdev)
+{
+ struct lvts_data *lvts_data;
+
+ lvts_data = (struct lvts_data *)platform_get_drvdata(pdev);
+
+ lvts_close(lvts_data);
+
+ return 0;
+}
+
+int lvts_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct lvts_data *lvts_data;
+
+ lvts_data = (struct lvts_data *)platform_get_drvdata(pdev);
+
+ lvts_close(lvts_data);
+
+ return 0;
+}
+
+int lvts_resume(struct platform_device *pdev)
+{
+ int ret;
+ struct lvts_data *lvts_data;
+
+ lvts_data = (struct lvts_data *)platform_get_drvdata(pdev);
+
+ ret = lvts_init(lvts_data);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+MODULE_AUTHOR("Yu-Chia Chang <ethan.chang@xxxxxxxxxxxx>");
+MODULE_AUTHOR("Michael Kao <michael.kao@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MediaTek soc temperature driver");
+MODULE_LICENSE("GPL v2");

Regards,
Angelo