[v2,2/2] thermal: sprd: Add Spreadtrum thermal driver support
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Message ID dd3303a956e7dd5c065ac2b92b1dea7ee5d1df17.1575978484.git.baolin.wang7@gmail.com
State New
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Series
  • [v2,1/2] dt-bindings: thermal: sprd: Add the Spreadtrum thermal documentation
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Commit Message

Baolin Wang Dec. 10, 2019, 12:07 p.m. UTC
From: Freeman Liu <freeman.liu@unisoc.com>

This patch adds the support for Spreadtrum thermal sensor controller,
which can support maximum 8 sensors.

Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
---
Changes from v1:
 - None.
---
 drivers/thermal/Kconfig        |    7 +
 drivers/thermal/Makefile       |    1 +
 drivers/thermal/sprd_thermal.c |  548 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 556 insertions(+)
 create mode 100644 drivers/thermal/sprd_thermal.c

Comments

Baolin Wang Dec. 23, 2019, 6:31 a.m. UTC | #1
Hi Rui and Daniel,

On Tue, Dec 10, 2019 at 8:08 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>
> From: Freeman Liu <freeman.liu@unisoc.com>
>
> This patch adds the support for Spreadtrum thermal sensor controller,
> which can support maximum 8 sensors.
>
> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> ---
> Changes from v1:
>  - None.
> ---

Any comments for this patch? Thanks.
Daniel Lezcano Dec. 23, 2019, 7:42 a.m. UTC | #2
Hi Baolin,

On 23/12/2019 07:31, Baolin Wang wrote:
> Hi Rui and Daniel,
> 
> On Tue, Dec 10, 2019 at 8:08 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>>
>> From: Freeman Liu <freeman.liu@unisoc.com>
>>
>> This patch adds the support for Spreadtrum thermal sensor controller,
>> which can support maximum 8 sensors.
>>
>> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
>> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
>> ---
>> Changes from v1:
>>  - None.
>> ---
> 
> Any comments for this patch? Thanks.

as it is a new driver, it takes a bit more time for the review.

By the way, is there any open documentation for the hardware?

Thanks

  -- Daniel
Baolin Wang Dec. 23, 2019, 7:48 a.m. UTC | #3
Hi Daniel,

On Mon, Dec 23, 2019 at 3:42 PM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
>
> Hi Baolin,
>
> On 23/12/2019 07:31, Baolin Wang wrote:
> > Hi Rui and Daniel,
> >
> > On Tue, Dec 10, 2019 at 8:08 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
> >>
> >> From: Freeman Liu <freeman.liu@unisoc.com>
> >>
> >> This patch adds the support for Spreadtrum thermal sensor controller,
> >> which can support maximum 8 sensors.
> >>
> >> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
> >> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> >> ---
> >> Changes from v1:
> >>  - None.
> >> ---
> >
> > Any comments for this patch? Thanks.
>
> as it is a new driver, it takes a bit more time for the review.

Sure, thanks.

>
> By the way, is there any open documentation for the hardware?

Unfortunately, our company did not supply public documentation for
thermal until now.
Baolin Wang Jan. 16, 2020, 8:52 a.m. UTC | #4
Hi Daniel,

On Mon, Dec 23, 2019 at 3:48 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>
> Hi Daniel,
>
> On Mon, Dec 23, 2019 at 3:42 PM Daniel Lezcano
> <daniel.lezcano@linaro.org> wrote:
> >
> >
> > Hi Baolin,
> >
> > On 23/12/2019 07:31, Baolin Wang wrote:
> > > Hi Rui and Daniel,
> > >
> > > On Tue, Dec 10, 2019 at 8:08 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
> > >>
> > >> From: Freeman Liu <freeman.liu@unisoc.com>
> > >>
> > >> This patch adds the support for Spreadtrum thermal sensor controller,
> > >> which can support maximum 8 sensors.
> > >>
> > >> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
> > >> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> > >> ---
> > >> Changes from v1:
> > >>  - None.
> > >> ---
> > >
> > > Any comments for this patch? Thanks.
> >

Sorry for reminding you again, could you have a look about this patch
when you feel free? Thanks.
Daniel Lezcano Jan. 16, 2020, 9:41 p.m. UTC | #5
Hi Baolin,

On 16/01/2020 09:52, Baolin Wang wrote:
> Hi Daniel,
> 
> On Mon, Dec 23, 2019 at 3:48 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>>
>> Hi Daniel,
>>
>> On Mon, Dec 23, 2019 at 3:42 PM Daniel Lezcano
>> <daniel.lezcano@linaro.org> wrote:
>>>
>>>
>>> Hi Baolin,
>>>
>>> On 23/12/2019 07:31, Baolin Wang wrote:
>>>> Hi Rui and Daniel,
>>>>
>>>> On Tue, Dec 10, 2019 at 8:08 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>>>>>
>>>>> From: Freeman Liu <freeman.liu@unisoc.com>
>>>>>
>>>>> This patch adds the support for Spreadtrum thermal sensor controller,
>>>>> which can support maximum 8 sensors.
>>>>>
>>>>> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
>>>>> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
>>>>> ---
>>>>> Changes from v1:
>>>>>  - None.
>>>>> ---
>>>>
>>>> Any comments for this patch? Thanks.
>>>
> 
> Sorry for reminding you again, could you have a look about this patch
> when you feel free? Thanks.

Thanks for heads up and sorry for the delay. I began to review the
patch, I'll send the review tomorrow.
Daniel Lezcano Jan. 17, 2020, 11:52 a.m. UTC | #6
On 10/12/2019 13:07, Baolin Wang wrote:
> From: Freeman Liu <freeman.liu@unisoc.com>
> 
> This patch adds the support for Spreadtrum thermal sensor controller,
> which can support maximum 8 sensors.
> 
> Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> ---
> Changes from v1:
>  - None.
> ---
>  drivers/thermal/Kconfig        |    7 +
>  drivers/thermal/Makefile       |    1 +
>  drivers/thermal/sprd_thermal.c |  548 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 556 insertions(+)
>  create mode 100644 drivers/thermal/sprd_thermal.c
> 
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 59b79fc..646873d 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -429,4 +429,11 @@ config UNIPHIER_THERMAL
>  	  Enable this to plug in UniPhier on-chip PVT thermal driver into the
>  	  thermal framework. The driver supports CPU thermal zone temperature
>  	  reporting and a couple of trip points.
> +
> +config SPRD_THERMAL
> +	tristate "Temperature sensor on Spreadtrum SoCs"
> +	depends on ARCH_SPRD || COMPILE_TEST
> +	help
> +	  Support for the Spreadtrum thermal sensor driver in the Linux thermal
> +	  framework.
>  endif
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index baeb70b..544d867 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -55,3 +55,4 @@ obj-$(CONFIG_GENERIC_ADC_THERMAL)	+= thermal-generic-adc.o
>  obj-$(CONFIG_ZX2967_THERMAL)	+= zx2967_thermal.o
>  obj-$(CONFIG_UNIPHIER_THERMAL)	+= uniphier_thermal.o
>  obj-$(CONFIG_AMLOGIC_THERMAL)     += amlogic_thermal.o
> +obj-$(CONFIG_SPRD_THERMAL)	+= sprd_thermal.o
> diff --git a/drivers/thermal/sprd_thermal.c b/drivers/thermal/sprd_thermal.c
> new file mode 100644
> index 0000000..d9b6074
> --- /dev/null
> +++ b/drivers/thermal/sprd_thermal.c
> @@ -0,0 +1,548 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2019 Spreadtrum Communications Inc.
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define SPRD_THM_CTL			0x0
> +#define SPRD_THM_INT_EN			0x4
> +#define SPRD_THM_INT_STS		0x8
> +#define SPRD_THM_INT_RAW_STS		0xc
> +#define SPRD_THM_DET_PERIOD		0x10
> +#define SPRD_THM_INT_CLR		0x14
> +#define SPRD_THM_INT_CLR_ST		0x18
> +#define SPRD_THM_MON_PERIOD		0x4c
> +#define SPRD_THM_MON_CTL		0x50
> +#define SPRD_THM_INTERNAL_STS1		0x54
> +#define SPRD_THM_RAW_READ_MSK		0x3ff
> +
> +#define SPRD_THM_OFFSET(id)		((id) * 0x4)
> +#define SPRD_THM_TEMP(id)		(SPRD_THM_OFFSET(id) + 0x5c)
> +#define SPRD_THM_THRES(id)		(SPRD_THM_OFFSET(id) + 0x2c)
> +
> +#define SPRD_THM_SEN(id)		BIT((id) + 2)
> +#define SPRD_THM_SEN_OVERHEAT_EN(id)	BIT((id) + 8)
> +#define SPRD_THM_SEN_OVERHEAT_ALARM_EN(id)	BIT((id) + 0)
> +
> +/* bits definitions for register THM_CTL */
> +#define SPRD_THM_SET_RDY_ST		BIT(13)
> +#define SPRD_THM_SET_RDY		BIT(12)
> +#define SPRD_THM_MON_EN			BIT(1)
> +#define SPRD_THM_EN			BIT(0)
> +
> +/* bits definitions for register THM_INT_CTL */
> +#define SPRD_THM_BIT_INT_EN		BIT(26)
> +#define SPRD_THM_OVERHEAT_EN		BIT(25)
> +#define SPRD_THM_OTP_TRIP_SHIFT		10
> +
> +/* bits definitions for register SPRD_THM_INTERNAL_STS1 */
> +#define SPRD_THM_TEMPER_RDY		BIT(0)
> +
> +#define SPRD_THM_DET_PERIOD_DATA	0x800
> +#define SPRD_THM_DET_PERIOD_MASK	GENMASK(19, 0)
> +#define SPRD_THM_MON_MODE		0x7
> +#define SPRD_THM_MON_MODE_MASK		GENMASK(3, 0)
> +#define SPRD_THM_MON_PERIOD_DATA	0x10
> +#define SPRD_THM_MON_PERIOD_MASK	GENMASK(15, 0)
> +#define SPRD_THM_THRES_MASK		GENMASK(19, 0)
> +#define SPRD_THM_INT_CLR_MASK		GENMASK(24, 0)
> +
> +/* thermal sensor calibration parameters */
> +#define SPRD_THM_TEMP_LOW		-40000
> +#define SPRD_THM_TEMP_HIGH		120000
> +#define SPRD_THM_OTP_TEMP		120000
> +#define SPRD_THM_HOT_TEMP		75000
> +#define SPRD_THM_RAW_DATA_LOW		0
> +#define SPRD_THM_RAW_DATA_HIGH		1000
> +#define SPRD_THM_SEN_NUM		8
> +#define SPRD_THM_DT_OFFSET		24
> +#define SPRD_THM_RATION_OFFSET		17
> +#define SPRD_THM_RATION_SIGN		16
> +
> +#define SPRD_THM_RDYST_POLLING_TIME	10
> +#define SPRD_THM_RDYST_TIMEOUT		700
> +#define SPRD_THM_TEMP_READY_POLL_TIME	10000
> +#define SPRD_THM_TEMP_READY_TIMEOUT	600000
> +#define SPRD_THM_MAX_SENSOR		8
> +
> +struct sprd_thermal_sensor {
> +	struct thermal_zone_device *thmzone_dev;
> +	struct sprd_thermal_data *data;
> +	struct device *dev;
> +	bool ready;
> +	int cal_slope;
> +	int cal_offset;
> +	int last_temp;
> +	int id;
> +};
> +
> +struct sprd_thermal_data {
> +	const struct sprd_thm_variant_data *var_data;
> +	struct sprd_thermal_sensor *sensor[SPRD_THM_MAX_SENSOR];
> +	struct clk *clk;
> +	void __iomem *base;
> +	u32 ratio_off;
> +	u32 ratio_sign;
> +	int nr_sensors;
> +};
> +
> +/*
> + * The conversion between ADC and temperature is based on linear relationship,
> + * and use idea_k to specify the slope and ideal_b to specify the offset.
> + *
> + * Since different Spreadtrum SoCs have different ideal_k and ideal_b,
> + * we should save ideal_k and ideal_b in the device data structure.
> + */
> +struct sprd_thm_variant_data {
> +	u32 ideal_k;
> +	u32 ideal_b;
> +};
> +
> +static const struct sprd_thm_variant_data ums512_data = {
> +	.ideal_k = 262,
> +	.ideal_b = 66400,
> +};
> +
> +static inline void sprd_thm_update_bits(void __iomem *reg, u32 mask, u32 val)
> +{
> +	u32 tmp, orig;
> +
> +	orig = readl(reg);
> +	tmp = orig & ~mask;
> +	tmp |= val & mask;
> +	writel(tmp, reg);

Please have a look at linux/bitops.h and check if a macro does not fit
your need (eg. set_mask_bits and set_bit). AFAICT, most of the operation
are clear/set bits.

> +}
> +
> +static int sprd_thm_cal_read(struct device_node *np, const char *cell_id,
> +			     u32 *val)
> +{
> +	struct nvmem_cell *cell;
> +	void *buf;
> +	size_t len;
> +
> +	cell = of_nvmem_cell_get(np, cell_id);
> +	if (IS_ERR(cell))
> +		return PTR_ERR(cell);
> +
> +	buf = nvmem_cell_read(cell, &len);
> +	nvmem_cell_put(cell);
> +	if (IS_ERR(buf))
> +		return PTR_ERR(buf);
> +
> +	memcpy(val, buf, min(len, sizeof(u32)));

I'm probably nitpicking but what if the len is different from the u32,
the result will be inconsistent. If that can happen, wouldn't make sense
to bail out before with an error ?

> +	kfree(buf);
> +	return 0;
> +}
> +
> +static int sprd_thm_senor_calibration(struct device_node *np,
> +				      struct sprd_thermal_data *thm,
> +				      struct sprd_thermal_sensor *sen)

"senor_calibration" or "sensor_calibration" ?

> +{
> +	int ret;
> +	/*
> +	 * According to thermal datasheet, the default calibration offset is 64,
> +	 * and the default ratio is 1000.
> +	 */
> +	int dt_offset = 64, ratio = 1000;
> +
> +	ret = sprd_thm_cal_read(np, "sen_delta_cal", &dt_offset);
> +	if (ret)
> +		return ret;
> +
> +	if (thm->ratio_sign == 1)
> +		ratio = 1000 - thm->ratio_off;
> +	else
> +		ratio = 1000 + thm->ratio_off;

Store ratio_sign = -1 | 1 at init time, then :

  ratio += ratio_sign * thm->ratio_off

> +	/*
> +	 * According to the ideal slope K and ideal offset B, combined with
> +	 * calibration value of thermal from efuse, then calibrate the real
> +	 * slope k and offset b:
> +	 * k_cal = (k * ratio) / 1000.
> +	 * b_cal = b + (dt_offset - 64) * 500.
> +	 */
> +	sen->cal_slope = (thm->var_data->ideal_k * ratio) / 1000;
> +	sen->cal_offset = thm->var_data->ideal_b + (dt_offset - 128) * 250;
> +
> +	return 0;
> +}
> +
> +static int sprd_thm_rawdata_to_temp(struct sprd_thermal_sensor *sen,
> +				    u32 rawdata)
> +{
> +	if (rawdata < SPRD_THM_RAW_DATA_LOW)
> +		rawdata = SPRD_THM_RAW_DATA_LOW;
> +	else if (rawdata > SPRD_THM_RAW_DATA_HIGH)
> +		rawdata = SPRD_THM_RAW_DATA_HIGH;

check clamp() macro in kernel.h

> +	/*
> +	 * According to the thermal datasheet, the formula of converting
> +	 * adc value to the temperature value should be:
> +	 * T_final = k_cal * x - b_cal.
> +	 */
> +	return sen->cal_slope * rawdata - sen->cal_offset;
> +}
> +
> +static int sprd_thm_temp_to_rawdata(int temp, struct sprd_thermal_sensor *sen)
> +{
> +	u32 val;
> +
> +	if (temp < SPRD_THM_TEMP_LOW)
> +		temp = SPRD_THM_TEMP_LOW;
> +	else if (temp > SPRD_THM_TEMP_HIGH)
> +		temp = SPRD_THM_TEMP_HIGH;

check clamp() macro in kernel.h

> +	/*
> +	 * According to the thermal datasheet, the formula of converting
> +	 * adc value to the temperature value should be:
> +	 * T_final = k_cal * x - b_cal.
> +	 */
> +	val = (temp + sen->cal_offset) / sen->cal_slope;
> +
> +	return val >= SPRD_THM_RAW_DATA_HIGH ? (SPRD_THM_RAW_DATA_HIGH - 1) : val;

check clamp() macro in kernel.h

> +}
> +
> +static int sprd_thm_read_temp(void *devdata, int *temp)
> +{
> +	struct sprd_thermal_sensor *sen = devdata;
> +	int sensor_temp;
> +	u32 data;
> +
> +	data = readl(sen->data->base + SPRD_THM_TEMP(sen->id)) &
> +		SPRD_THM_RAW_READ_MSK;
> +
> +	if (sen->ready) {
> +		sensor_temp = sprd_thm_rawdata_to_temp(sen, data);
> +		sen->last_temp = sensor_temp;
> +		*temp = sensor_temp;

If the initialization is done in the right order and using the
THERMAL_DEVICE_DISABLED, this test should not be needed. And de facto,
neither the last_temp.

As a side note, if the sensor is not ready it should return an error
like -EBUSY instead of the previous value.

> +	} else {
> +		/*
> +		 * If the sensor is not ready, then just return last
> +		 * temperature value.
> +		 */
> +		*temp = sen->last_temp;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops sprd_thm_ops = {
> +	.get_temp = sprd_thm_read_temp,
> +};
> +
> +static int sprd_thm_poll_ready_status(struct sprd_thermal_data *thm)
> +{
> +	u32 val;
> +	int ret;
> +
> +	/*
> +	 * Wait for thermal ready status before configuring thermal parameters.
> +	 */
> +	ret = readl_poll_timeout(thm->base + SPRD_THM_CTL, val,
> +				 !(val & SPRD_THM_SET_RDY_ST),
> +				 SPRD_THM_RDYST_POLLING_TIME,
> +				 SPRD_THM_RDYST_TIMEOUT);
> +	if (ret)
> +		return ret;
> +
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_MON_EN,
> +			     SPRD_THM_MON_EN);
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SET_RDY,
> +			     SPRD_THM_SET_RDY);
> +	return 0;
> +}
> +
> +static int sprd_thm_wait_temp_ready(struct sprd_thermal_data *thm)
> +{
> +	u32 val;
> +
> +	/* Wait for first temperature data ready before reading temperature */
> +	return readl_poll_timeout(thm->base + SPRD_THM_INTERNAL_STS1, val,
> +				  !(val & SPRD_THM_TEMPER_RDY),
> +				  SPRD_THM_TEMP_READY_POLL_TIME,
> +				  SPRD_THM_TEMP_READY_TIMEOUT);
> +}
> +
> +static int sprd_thm_set_ready(struct sprd_thermal_data *thm)
> +{
> +	int ret;
> +
> +	ret = sprd_thm_poll_ready_status(thm);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * Clear interrupt status, enable thermal interrupt and enable thermal.
> +	 */
> +	writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
> +	sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
> +			     SPRD_THM_BIT_INT_EN, SPRD_THM_BIT_INT_EN);
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> +			     SPRD_THM_EN, SPRD_THM_EN);

Why enabling the interrupt while there is no handler for it?

> +	return 0;
> +}
> +
> +static void sprd_thm_sensor_init(struct sprd_thermal_data *thm,
> +				 struct sprd_thermal_sensor *sen)
> +{
> +	u32 otp_rawdata, hot_rawdata;
> +
> +	otp_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_OTP_TEMP, sen);
> +	hot_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_HOT_TEMP, sen);
> +
> +	/* Enable the sensor' overheat temperature protection interrupt */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
> +			     SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id),
> +			     SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id));
> +
> +	/* Set the sensor' overheat and hot threshold temperature */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_THRES(sen->id),
> +			     SPRD_THM_THRES_MASK,
> +			     (otp_rawdata << SPRD_THM_OTP_TRIP_SHIFT) |
> +			     hot_rawdata);
> +
> +	/* Enable the corresponding sensor */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SEN(sen->id),
> +			     SPRD_THM_SEN(sen->id));
> +}
> +
> +static void sprd_thm_para_config(struct sprd_thermal_data *thm)
> +{
> +	/* Set the period of two valid temperature detection action */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_DET_PERIOD,
> +			     SPRD_THM_DET_PERIOD_MASK, SPRD_THM_DET_PERIOD);
> +
> +	/* Set the sensors' monitor mode */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_MON_CTL,
> +			     SPRD_THM_MON_MODE_MASK, SPRD_THM_MON_MODE);
> +
> +	/* Set the sensors' monitor period */
> +	sprd_thm_update_bits(thm->base + SPRD_THM_MON_PERIOD,
> +			     SPRD_THM_MON_PERIOD_MASK, SPRD_THM_MON_PERIOD);
> +}
> +
> +static int sprd_thm_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct device_node *sen_child;
> +	struct sprd_thermal_data *thm;
> +	struct sprd_thermal_sensor *sen;
> +	const struct sprd_thm_variant_data *pdata;
> +	int ret, i;
> +
> +	pdata = of_device_get_match_data(&pdev->dev);
> +	if (!pdata) {
> +		dev_err(&pdev->dev, "No matching driver data found\n");
> +		return -EINVAL;
> +	}
> +
> +	thm = devm_kzalloc(&pdev->dev, sizeof(*thm), GFP_KERNEL);
> +	if (!thm)
> +		return -ENOMEM;
> +
> +	thm->var_data = pdata;
> +	thm->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (!thm->base)
> +		return -ENOMEM;
> +
> +	thm->nr_sensors = of_get_child_count(np);
> +	if (thm->nr_sensors == 0 || thm->nr_sensors > SPRD_THM_MAX_SENSOR) {
> +		dev_err(&pdev->dev, "incorrect sensor count\n");
> +		return -EINVAL;
> +	}
> +
> +	thm->clk = devm_clk_get(&pdev->dev, "enable");
> +	if (IS_ERR(thm->clk)) {
> +		dev_err(&pdev->dev, "failed to get enable clock\n");
> +		return PTR_ERR(thm->clk);
> +	}
> +
> +	ret = clk_prepare_enable(thm->clk);
> +	if (ret)
> +		return ret;
> +
> +	sprd_thm_para_config(thm);
> +
> +	ret = sprd_thm_cal_read(np, "thm_sign_cal", &thm->ratio_sign);
> +	if (ret)
> +		goto disable_clk;
> +
> +	ret = sprd_thm_cal_read(np, "thm_ratio_cal", &thm->ratio_off);
> +	if (ret)
> +		goto disable_clk;
> +
> +	for_each_child_of_node(np, sen_child) {
> +		sen = devm_kzalloc(&pdev->dev, sizeof(*sen), GFP_KERNEL);
> +		if (!sen) {
> +			ret = -ENOMEM;
> +			goto disable_clk;
> +		}
> +
> +		sen->ready = false;
> +		sen->data = thm;
> +		sen->dev = &pdev->dev;
> +
> +		ret = of_property_read_u32(sen_child, "reg", &sen->id);
> +		if (ret) {
> +			dev_err(&pdev->dev, "get sensor reg failed");
> +			goto disable_clk;
> +		}
> +
> +		ret = sprd_thm_senor_calibration(sen_child, thm, sen);
> +		if (ret) {
> +			dev_err(&pdev->dev, "efuse cal analysis failed");
> +			goto disable_clk;
> +		}
> +
> +		sprd_thm_sensor_init(thm, sen);
> +
> +		sen->thmzone_dev =
> +			devm_thermal_zone_of_sensor_register(sen->dev, sen->id,
> +							     sen, &sprd_thm_ops);
> +		if (IS_ERR(sen->thmzone_dev)) {
> +			dev_err(&pdev->dev, "register thermal zone failed %d\n",
> +				sen->id);
> +			ret = PTR_ERR(sen->thmzone_dev);
> +			goto disable_clk;
> +		}
> +
> +		thm->sensor[sen->id] = sen;
> +	}
> +
> +	ret = sprd_thm_set_ready(thm);
> +	if (ret)
> +		goto disable_clk;
> +
> +	ret = sprd_thm_wait_temp_ready(thm);
> +	if (ret)
> +		goto disable_clk;
> +
> +	for (i = 0; i < thm->nr_sensors; i++)
> +		thm->sensor[i]->ready = true;

You should replace 'ready' by the THERMAL_DEVICE_ENABLED/DISABLED (grep
it on the other drivers for reference) and/or call
devm_thermal_zone_of_sensor_register() here.

> +	platform_set_drvdata(pdev, thm);
> +	return 0;
> +
> +disable_clk:
> +	clk_disable_unprepare(thm->clk);
> +	return ret;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static void sprd_thm_hw_suspend(struct sprd_thermal_data *thm)
> +{
> +	int i;
> +
> +	for (i = 0; i < thm->nr_sensors; i++) {
> +		sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> +				     SPRD_THM_SEN(thm->sensor[i]->id), 0);
> +	}
> +
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> +			     SPRD_THM_EN, 0x0);
> +}
> +
> +static int sprd_thm_suspend(struct device *dev)
> +{
> +	struct sprd_thermal_data *thm = dev_get_drvdata(dev);
> +	int i;
> +
> +	for (i = 0; i < thm->nr_sensors; i++)
> +		thm->sensor[i]->ready = false;
> +
> +	sprd_thm_hw_suspend(thm);
> +	clk_disable_unprepare(thm->clk);
> +
> +	return 0;
> +}
> +
> +static int sprd_thm_hw_resume(struct sprd_thermal_data *thm)
> +{
> +	int ret, i;
> +
> +	for (i = 0; i < thm->nr_sensors; i++) {
> +		sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> +				     SPRD_THM_SEN(thm->sensor[i]->id),
> +				     SPRD_THM_SEN(thm->sensor[i]->id));
> +	}
> +
> +	ret = sprd_thm_poll_ready_status(thm);
> +	if (ret)
> +		return ret;
> +
> +	writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
> +	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> +			     SPRD_THM_EN, SPRD_THM_EN);
> +	return sprd_thm_wait_temp_ready(thm);
> +}
> +
> +static int sprd_thm_resume(struct device *dev)
> +{
> +	struct sprd_thermal_data *thm = dev_get_drvdata(dev);
> +	int ret, i;
> +
> +	ret = clk_prepare_enable(thm->clk);
> +	if (ret)
> +		return ret;
> +
> +	ret = sprd_thm_hw_resume(thm);
> +	if (ret)
> +		goto disable_clk;
> +
> +	for (i = 0; i < thm->nr_sensors; i++)
> +		thm->sensor[i]->ready = true;
> +
> +	return 0;
> +
> +disable_clk:
> +	clk_disable_unprepare(thm->clk);
> +	return ret;
> +}
> +#endif
> +
> +static int sprd_thm_remove(struct platform_device *pdev)
> +{
> +	struct sprd_thermal_data *thm = platform_get_drvdata(pdev);
> +	int i;
> +
> +	for (i = 0; i < thm->nr_sensors; i++) {
> +		devm_thermal_zone_of_sensor_unregister(&pdev->dev,
> +						       thm->sensor[i]->thmzone_dev);
> +	}
> +
> +	clk_disable_unprepare(thm->clk);
> +	return 0;
> +}
> +
> +static const struct of_device_id sprd_thermal_of_match[] = {
> +	{ .compatible = "sprd,ums512-thermal", .data = &ums512_data },
> +	{ },
> +};
> +
> +static const struct dev_pm_ops sprd_thermal_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(sprd_thm_suspend, sprd_thm_resume)
> +};
> +
> +static struct platform_driver sprd_thermal_driver = {
> +	.probe = sprd_thm_probe,
> +	.remove = sprd_thm_remove,
> +	.driver = {
> +		.name = "sprd-thermal",
> +		.pm = &sprd_thermal_pm_ops,
> +		.of_match_table = sprd_thermal_of_match,
> +	},
> +};
> +
> +module_platform_driver(sprd_thermal_driver);
> +
> +MODULE_AUTHOR("Freeman Liu <freeman.liu@unisoc.com>");
> +MODULE_DESCRIPTION("Spreadtrum thermal driver");
> +MODULE_LICENSE("GPL v2");
>
Baolin Wang Jan. 19, 2020, 7:37 a.m. UTC | #7
Hi Daniel,

On Fri, Jan 17, 2020 at 7:52 PM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
> On 10/12/2019 13:07, Baolin Wang wrote:
> > From: Freeman Liu <freeman.liu@unisoc.com>
> >
> > This patch adds the support for Spreadtrum thermal sensor controller,
> > which can support maximum 8 sensors.
> >
> > Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
> > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> > ---
> > Changes from v1:
> >  - None.
> > ---

> > +
> > +struct sprd_thermal_sensor {
> > +     struct thermal_zone_device *thmzone_dev;
> > +     struct sprd_thermal_data *data;
> > +     struct device *dev;
> > +     bool ready;
> > +     int cal_slope;
> > +     int cal_offset;
> > +     int last_temp;
> > +     int id;
> > +};
> > +
> > +struct sprd_thermal_data {
> > +     const struct sprd_thm_variant_data *var_data;
> > +     struct sprd_thermal_sensor *sensor[SPRD_THM_MAX_SENSOR];
> > +     struct clk *clk;
> > +     void __iomem *base;
> > +     u32 ratio_off;
> > +     u32 ratio_sign;
> > +     int nr_sensors;
> > +};
> > +
> > +/*
> > + * The conversion between ADC and temperature is based on linear relationship,
> > + * and use idea_k to specify the slope and ideal_b to specify the offset.
> > + *
> > + * Since different Spreadtrum SoCs have different ideal_k and ideal_b,
> > + * we should save ideal_k and ideal_b in the device data structure.
> > + */
> > +struct sprd_thm_variant_data {
> > +     u32 ideal_k;
> > +     u32 ideal_b;
> > +};
> > +
> > +static const struct sprd_thm_variant_data ums512_data = {
> > +     .ideal_k = 262,
> > +     .ideal_b = 66400,
> > +};
> > +
> > +static inline void sprd_thm_update_bits(void __iomem *reg, u32 mask, u32 val)
> > +{
> > +     u32 tmp, orig;
> > +
> > +     orig = readl(reg);
> > +     tmp = orig & ~mask;
> > +     tmp |= val & mask;
> > +     writel(tmp, reg);
>
> Please have a look at linux/bitops.h and check if a macro does not fit
> your need (eg. set_mask_bits and set_bit). AFAICT, most of the operation
> are clear/set bits.

We are updating a register here, not updating a vriable. So I think it
is not helpful with using set_mask_bits or set_bit.

>
> > +}
> > +
> > +static int sprd_thm_cal_read(struct device_node *np, const char *cell_id,
> > +                          u32 *val)
> > +{
> > +     struct nvmem_cell *cell;
> > +     void *buf;
> > +     size_t len;
> > +
> > +     cell = of_nvmem_cell_get(np, cell_id);
> > +     if (IS_ERR(cell))
> > +             return PTR_ERR(cell);
> > +
> > +     buf = nvmem_cell_read(cell, &len);
> > +     nvmem_cell_put(cell);
> > +     if (IS_ERR(buf))
> > +             return PTR_ERR(buf);
> > +
> > +     memcpy(val, buf, min(len, sizeof(u32)));
>
> I'm probably nitpicking but what if the len is different from the u32,
> the result will be inconsistent. If that can happen, wouldn't make sense
> to bail out before with an error ?

OK. Will change to give some error.

>
> > +     kfree(buf);
> > +     return 0;
> > +}
> > +
> > +static int sprd_thm_senor_calibration(struct device_node *np,
> > +                                   struct sprd_thermal_data *thm,
> > +                                   struct sprd_thermal_sensor *sen)
>
> "senor_calibration" or "sensor_calibration" ?

Sure.

>
> > +{
> > +     int ret;
> > +     /*
> > +      * According to thermal datasheet, the default calibration offset is 64,
> > +      * and the default ratio is 1000.
> > +      */
> > +     int dt_offset = 64, ratio = 1000;
> > +
> > +     ret = sprd_thm_cal_read(np, "sen_delta_cal", &dt_offset);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (thm->ratio_sign == 1)
> > +             ratio = 1000 - thm->ratio_off;
> > +     else
> > +             ratio = 1000 + thm->ratio_off;
>
> Store ratio_sign = -1 | 1 at init time, then :
>
>   ratio += ratio_sign * thm->ratio_off

OK.

>
> > +     /*
> > +      * According to the ideal slope K and ideal offset B, combined with
> > +      * calibration value of thermal from efuse, then calibrate the real
> > +      * slope k and offset b:
> > +      * k_cal = (k * ratio) / 1000.
> > +      * b_cal = b + (dt_offset - 64) * 500.
> > +      */
> > +     sen->cal_slope = (thm->var_data->ideal_k * ratio) / 1000;
> > +     sen->cal_offset = thm->var_data->ideal_b + (dt_offset - 128) * 250;
> > +
> > +     return 0;
> > +}
> > +
> > +static int sprd_thm_rawdata_to_temp(struct sprd_thermal_sensor *sen,
> > +                                 u32 rawdata)
> > +{
> > +     if (rawdata < SPRD_THM_RAW_DATA_LOW)
> > +             rawdata = SPRD_THM_RAW_DATA_LOW;
> > +     else if (rawdata > SPRD_THM_RAW_DATA_HIGH)
> > +             rawdata = SPRD_THM_RAW_DATA_HIGH;
>
> check clamp() macro in kernel.h

Yes, will do.

>
> > +     /*
> > +      * According to the thermal datasheet, the formula of converting
> > +      * adc value to the temperature value should be:
> > +      * T_final = k_cal * x - b_cal.
> > +      */
> > +     return sen->cal_slope * rawdata - sen->cal_offset;
> > +}
> > +
> > +static int sprd_thm_temp_to_rawdata(int temp, struct sprd_thermal_sensor *sen)
> > +{
> > +     u32 val;
> > +
> > +     if (temp < SPRD_THM_TEMP_LOW)
> > +             temp = SPRD_THM_TEMP_LOW;
> > +     else if (temp > SPRD_THM_TEMP_HIGH)
> > +             temp = SPRD_THM_TEMP_HIGH;
>
> check clamp() macro in kernel.h

OK.

>
> > +     /*
> > +      * According to the thermal datasheet, the formula of converting
> > +      * adc value to the temperature value should be:
> > +      * T_final = k_cal * x - b_cal.
> > +      */
> > +     val = (temp + sen->cal_offset) / sen->cal_slope;
> > +
> > +     return val >= SPRD_THM_RAW_DATA_HIGH ? (SPRD_THM_RAW_DATA_HIGH - 1) : val;
>
> check clamp() macro in kernel.h

OK.

>
> > +}
> > +
> > +static int sprd_thm_read_temp(void *devdata, int *temp)
> > +{
> > +     struct sprd_thermal_sensor *sen = devdata;
> > +     int sensor_temp;
> > +     u32 data;
> > +
> > +     data = readl(sen->data->base + SPRD_THM_TEMP(sen->id)) &
> > +             SPRD_THM_RAW_READ_MSK;
> > +
> > +     if (sen->ready) {
> > +             sensor_temp = sprd_thm_rawdata_to_temp(sen, data);
> > +             sen->last_temp = sensor_temp;
> > +             *temp = sensor_temp;
>
> If the initialization is done in the right order and using the
> THERMAL_DEVICE_DISABLED, this test should not be needed. And de facto,
> neither the last_temp.
>
> As a side note, if the sensor is not ready it should return an error
> like -EBUSY instead of the previous value.

OK. Will use THERMAL_DEVICE_DISABLED and remove 'last_temp'.

>
> > +     } else {
> > +             /*
> > +              * If the sensor is not ready, then just return last
> > +              * temperature value.
> > +              */
> > +             *temp = sen->last_temp;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct thermal_zone_of_device_ops sprd_thm_ops = {
> > +     .get_temp = sprd_thm_read_temp,
> > +};
> > +
> > +static int sprd_thm_poll_ready_status(struct sprd_thermal_data *thm)
> > +{
> > +     u32 val;
> > +     int ret;
> > +
> > +     /*
> > +      * Wait for thermal ready status before configuring thermal parameters.
> > +      */
> > +     ret = readl_poll_timeout(thm->base + SPRD_THM_CTL, val,
> > +                              !(val & SPRD_THM_SET_RDY_ST),
> > +                              SPRD_THM_RDYST_POLLING_TIME,
> > +                              SPRD_THM_RDYST_TIMEOUT);
> > +     if (ret)
> > +             return ret;
> > +
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_MON_EN,
> > +                          SPRD_THM_MON_EN);
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SET_RDY,
> > +                          SPRD_THM_SET_RDY);
> > +     return 0;
> > +}
> > +
> > +static int sprd_thm_wait_temp_ready(struct sprd_thermal_data *thm)
> > +{
> > +     u32 val;
> > +
> > +     /* Wait for first temperature data ready before reading temperature */
> > +     return readl_poll_timeout(thm->base + SPRD_THM_INTERNAL_STS1, val,
> > +                               !(val & SPRD_THM_TEMPER_RDY),
> > +                               SPRD_THM_TEMP_READY_POLL_TIME,
> > +                               SPRD_THM_TEMP_READY_TIMEOUT);
> > +}
> > +
> > +static int sprd_thm_set_ready(struct sprd_thermal_data *thm)
> > +{
> > +     int ret;
> > +
> > +     ret = sprd_thm_poll_ready_status(thm);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /*
> > +      * Clear interrupt status, enable thermal interrupt and enable thermal.
> > +      */
> > +     writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
> > +                          SPRD_THM_BIT_INT_EN, SPRD_THM_BIT_INT_EN);
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
> > +                          SPRD_THM_EN, SPRD_THM_EN);
>
> Why enabling the interrupt while there is no handler for it?

Our thermal controller integrates a hardware interrupt signal, which
means if the temperature is overheat, it will generate an interrupt
and notify the event to PMIC automatically to shutdown the system. So
we should enable the interrupt bits, but no need to register handler.

I will add some comments to explain this in next verison.

>
> > +     return 0;
> > +}
> > +
> > +static void sprd_thm_sensor_init(struct sprd_thermal_data *thm,
> > +                              struct sprd_thermal_sensor *sen)
> > +{
> > +     u32 otp_rawdata, hot_rawdata;
> > +
> > +     otp_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_OTP_TEMP, sen);
> > +     hot_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_HOT_TEMP, sen);
> > +
> > +     /* Enable the sensor' overheat temperature protection interrupt */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
> > +                          SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id),
> > +                          SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id));
> > +
> > +     /* Set the sensor' overheat and hot threshold temperature */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_THRES(sen->id),
> > +                          SPRD_THM_THRES_MASK,
> > +                          (otp_rawdata << SPRD_THM_OTP_TRIP_SHIFT) |
> > +                          hot_rawdata);
> > +
> > +     /* Enable the corresponding sensor */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SEN(sen->id),
> > +                          SPRD_THM_SEN(sen->id));
> > +}
> > +
> > +static void sprd_thm_para_config(struct sprd_thermal_data *thm)
> > +{
> > +     /* Set the period of two valid temperature detection action */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_DET_PERIOD,
> > +                          SPRD_THM_DET_PERIOD_MASK, SPRD_THM_DET_PERIOD);
> > +
> > +     /* Set the sensors' monitor mode */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_MON_CTL,
> > +                          SPRD_THM_MON_MODE_MASK, SPRD_THM_MON_MODE);
> > +
> > +     /* Set the sensors' monitor period */
> > +     sprd_thm_update_bits(thm->base + SPRD_THM_MON_PERIOD,
> > +                          SPRD_THM_MON_PERIOD_MASK, SPRD_THM_MON_PERIOD);
> > +}
> > +
> > +static int sprd_thm_probe(struct platform_device *pdev)
> > +{
> > +     struct device_node *np = pdev->dev.of_node;
> > +     struct device_node *sen_child;
> > +     struct sprd_thermal_data *thm;
> > +     struct sprd_thermal_sensor *sen;
> > +     const struct sprd_thm_variant_data *pdata;
> > +     int ret, i;
> > +
> > +     pdata = of_device_get_match_data(&pdev->dev);
> > +     if (!pdata) {
> > +             dev_err(&pdev->dev, "No matching driver data found\n");
> > +             return -EINVAL;
> > +     }
> > +
> > +     thm = devm_kzalloc(&pdev->dev, sizeof(*thm), GFP_KERNEL);
> > +     if (!thm)
> > +             return -ENOMEM;
> > +
> > +     thm->var_data = pdata;
> > +     thm->base = devm_platform_ioremap_resource(pdev, 0);
> > +     if (!thm->base)
> > +             return -ENOMEM;
> > +
> > +     thm->nr_sensors = of_get_child_count(np);
> > +     if (thm->nr_sensors == 0 || thm->nr_sensors > SPRD_THM_MAX_SENSOR) {
> > +             dev_err(&pdev->dev, "incorrect sensor count\n");
> > +             return -EINVAL;
> > +     }
> > +
> > +     thm->clk = devm_clk_get(&pdev->dev, "enable");
> > +     if (IS_ERR(thm->clk)) {
> > +             dev_err(&pdev->dev, "failed to get enable clock\n");
> > +             return PTR_ERR(thm->clk);
> > +     }
> > +
> > +     ret = clk_prepare_enable(thm->clk);
> > +     if (ret)
> > +             return ret;
> > +
> > +     sprd_thm_para_config(thm);
> > +
> > +     ret = sprd_thm_cal_read(np, "thm_sign_cal", &thm->ratio_sign);
> > +     if (ret)
> > +             goto disable_clk;
> > +
> > +     ret = sprd_thm_cal_read(np, "thm_ratio_cal", &thm->ratio_off);
> > +     if (ret)
> > +             goto disable_clk;
> > +
> > +     for_each_child_of_node(np, sen_child) {
> > +             sen = devm_kzalloc(&pdev->dev, sizeof(*sen), GFP_KERNEL);
> > +             if (!sen) {
> > +                     ret = -ENOMEM;
> > +                     goto disable_clk;
> > +             }
> > +
> > +             sen->ready = false;
> > +             sen->data = thm;
> > +             sen->dev = &pdev->dev;
> > +
> > +             ret = of_property_read_u32(sen_child, "reg", &sen->id);
> > +             if (ret) {
> > +                     dev_err(&pdev->dev, "get sensor reg failed");
> > +                     goto disable_clk;
> > +             }
> > +
> > +             ret = sprd_thm_senor_calibration(sen_child, thm, sen);
> > +             if (ret) {
> > +                     dev_err(&pdev->dev, "efuse cal analysis failed");
> > +                     goto disable_clk;
> > +             }
> > +
> > +             sprd_thm_sensor_init(thm, sen);
> > +
> > +             sen->thmzone_dev =
> > +                     devm_thermal_zone_of_sensor_register(sen->dev, sen->id,
> > +                                                          sen, &sprd_thm_ops);
> > +             if (IS_ERR(sen->thmzone_dev)) {
> > +                     dev_err(&pdev->dev, "register thermal zone failed %d\n",
> > +                             sen->id);
> > +                     ret = PTR_ERR(sen->thmzone_dev);
> > +                     goto disable_clk;
> > +             }
> > +
> > +             thm->sensor[sen->id] = sen;
> > +     }
> > +
> > +     ret = sprd_thm_set_ready(thm);
> > +     if (ret)
> > +             goto disable_clk;
> > +
> > +     ret = sprd_thm_wait_temp_ready(thm);
> > +     if (ret)
> > +             goto disable_clk;
> > +
> > +     for (i = 0; i < thm->nr_sensors; i++)
> > +             thm->sensor[i]->ready = true;
>
> You should replace 'ready' by the THERMAL_DEVICE_ENABLED/DISABLED (grep
> it on the other drivers for reference) and/or call
> devm_thermal_zone_of_sensor_register() here.

Sure. I think we missed THERMAL_DEVICE_ENABLED/DISABLED flag.

Thanks for your comments.

Patch
diff mbox series

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 59b79fc..646873d 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -429,4 +429,11 @@  config UNIPHIER_THERMAL
 	  Enable this to plug in UniPhier on-chip PVT thermal driver into the
 	  thermal framework. The driver supports CPU thermal zone temperature
 	  reporting and a couple of trip points.
+
+config SPRD_THERMAL
+	tristate "Temperature sensor on Spreadtrum SoCs"
+	depends on ARCH_SPRD || COMPILE_TEST
+	help
+	  Support for the Spreadtrum thermal sensor driver in the Linux thermal
+	  framework.
 endif
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index baeb70b..544d867 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -55,3 +55,4 @@  obj-$(CONFIG_GENERIC_ADC_THERMAL)	+= thermal-generic-adc.o
 obj-$(CONFIG_ZX2967_THERMAL)	+= zx2967_thermal.o
 obj-$(CONFIG_UNIPHIER_THERMAL)	+= uniphier_thermal.o
 obj-$(CONFIG_AMLOGIC_THERMAL)     += amlogic_thermal.o
+obj-$(CONFIG_SPRD_THERMAL)	+= sprd_thermal.o
diff --git a/drivers/thermal/sprd_thermal.c b/drivers/thermal/sprd_thermal.c
new file mode 100644
index 0000000..d9b6074
--- /dev/null
+++ b/drivers/thermal/sprd_thermal.c
@@ -0,0 +1,548 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2019 Spreadtrum Communications Inc.
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define SPRD_THM_CTL			0x0
+#define SPRD_THM_INT_EN			0x4
+#define SPRD_THM_INT_STS		0x8
+#define SPRD_THM_INT_RAW_STS		0xc
+#define SPRD_THM_DET_PERIOD		0x10
+#define SPRD_THM_INT_CLR		0x14
+#define SPRD_THM_INT_CLR_ST		0x18
+#define SPRD_THM_MON_PERIOD		0x4c
+#define SPRD_THM_MON_CTL		0x50
+#define SPRD_THM_INTERNAL_STS1		0x54
+#define SPRD_THM_RAW_READ_MSK		0x3ff
+
+#define SPRD_THM_OFFSET(id)		((id) * 0x4)
+#define SPRD_THM_TEMP(id)		(SPRD_THM_OFFSET(id) + 0x5c)
+#define SPRD_THM_THRES(id)		(SPRD_THM_OFFSET(id) + 0x2c)
+
+#define SPRD_THM_SEN(id)		BIT((id) + 2)
+#define SPRD_THM_SEN_OVERHEAT_EN(id)	BIT((id) + 8)
+#define SPRD_THM_SEN_OVERHEAT_ALARM_EN(id)	BIT((id) + 0)
+
+/* bits definitions for register THM_CTL */
+#define SPRD_THM_SET_RDY_ST		BIT(13)
+#define SPRD_THM_SET_RDY		BIT(12)
+#define SPRD_THM_MON_EN			BIT(1)
+#define SPRD_THM_EN			BIT(0)
+
+/* bits definitions for register THM_INT_CTL */
+#define SPRD_THM_BIT_INT_EN		BIT(26)
+#define SPRD_THM_OVERHEAT_EN		BIT(25)
+#define SPRD_THM_OTP_TRIP_SHIFT		10
+
+/* bits definitions for register SPRD_THM_INTERNAL_STS1 */
+#define SPRD_THM_TEMPER_RDY		BIT(0)
+
+#define SPRD_THM_DET_PERIOD_DATA	0x800
+#define SPRD_THM_DET_PERIOD_MASK	GENMASK(19, 0)
+#define SPRD_THM_MON_MODE		0x7
+#define SPRD_THM_MON_MODE_MASK		GENMASK(3, 0)
+#define SPRD_THM_MON_PERIOD_DATA	0x10
+#define SPRD_THM_MON_PERIOD_MASK	GENMASK(15, 0)
+#define SPRD_THM_THRES_MASK		GENMASK(19, 0)
+#define SPRD_THM_INT_CLR_MASK		GENMASK(24, 0)
+
+/* thermal sensor calibration parameters */
+#define SPRD_THM_TEMP_LOW		-40000
+#define SPRD_THM_TEMP_HIGH		120000
+#define SPRD_THM_OTP_TEMP		120000
+#define SPRD_THM_HOT_TEMP		75000
+#define SPRD_THM_RAW_DATA_LOW		0
+#define SPRD_THM_RAW_DATA_HIGH		1000
+#define SPRD_THM_SEN_NUM		8
+#define SPRD_THM_DT_OFFSET		24
+#define SPRD_THM_RATION_OFFSET		17
+#define SPRD_THM_RATION_SIGN		16
+
+#define SPRD_THM_RDYST_POLLING_TIME	10
+#define SPRD_THM_RDYST_TIMEOUT		700
+#define SPRD_THM_TEMP_READY_POLL_TIME	10000
+#define SPRD_THM_TEMP_READY_TIMEOUT	600000
+#define SPRD_THM_MAX_SENSOR		8
+
+struct sprd_thermal_sensor {
+	struct thermal_zone_device *thmzone_dev;
+	struct sprd_thermal_data *data;
+	struct device *dev;
+	bool ready;
+	int cal_slope;
+	int cal_offset;
+	int last_temp;
+	int id;
+};
+
+struct sprd_thermal_data {
+	const struct sprd_thm_variant_data *var_data;
+	struct sprd_thermal_sensor *sensor[SPRD_THM_MAX_SENSOR];
+	struct clk *clk;
+	void __iomem *base;
+	u32 ratio_off;
+	u32 ratio_sign;
+	int nr_sensors;
+};
+
+/*
+ * The conversion between ADC and temperature is based on linear relationship,
+ * and use idea_k to specify the slope and ideal_b to specify the offset.
+ *
+ * Since different Spreadtrum SoCs have different ideal_k and ideal_b,
+ * we should save ideal_k and ideal_b in the device data structure.
+ */
+struct sprd_thm_variant_data {
+	u32 ideal_k;
+	u32 ideal_b;
+};
+
+static const struct sprd_thm_variant_data ums512_data = {
+	.ideal_k = 262,
+	.ideal_b = 66400,
+};
+
+static inline void sprd_thm_update_bits(void __iomem *reg, u32 mask, u32 val)
+{
+	u32 tmp, orig;
+
+	orig = readl(reg);
+	tmp = orig & ~mask;
+	tmp |= val & mask;
+	writel(tmp, reg);
+}
+
+static int sprd_thm_cal_read(struct device_node *np, const char *cell_id,
+			     u32 *val)
+{
+	struct nvmem_cell *cell;
+	void *buf;
+	size_t len;
+
+	cell = of_nvmem_cell_get(np, cell_id);
+	if (IS_ERR(cell))
+		return PTR_ERR(cell);
+
+	buf = nvmem_cell_read(cell, &len);
+	nvmem_cell_put(cell);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	memcpy(val, buf, min(len, sizeof(u32)));
+
+	kfree(buf);
+	return 0;
+}
+
+static int sprd_thm_senor_calibration(struct device_node *np,
+				      struct sprd_thermal_data *thm,
+				      struct sprd_thermal_sensor *sen)
+{
+	int ret;
+	/*
+	 * According to thermal datasheet, the default calibration offset is 64,
+	 * and the default ratio is 1000.
+	 */
+	int dt_offset = 64, ratio = 1000;
+
+	ret = sprd_thm_cal_read(np, "sen_delta_cal", &dt_offset);
+	if (ret)
+		return ret;
+
+	if (thm->ratio_sign == 1)
+		ratio = 1000 - thm->ratio_off;
+	else
+		ratio = 1000 + thm->ratio_off;
+
+	/*
+	 * According to the ideal slope K and ideal offset B, combined with
+	 * calibration value of thermal from efuse, then calibrate the real
+	 * slope k and offset b:
+	 * k_cal = (k * ratio) / 1000.
+	 * b_cal = b + (dt_offset - 64) * 500.
+	 */
+	sen->cal_slope = (thm->var_data->ideal_k * ratio) / 1000;
+	sen->cal_offset = thm->var_data->ideal_b + (dt_offset - 128) * 250;
+
+	return 0;
+}
+
+static int sprd_thm_rawdata_to_temp(struct sprd_thermal_sensor *sen,
+				    u32 rawdata)
+{
+	if (rawdata < SPRD_THM_RAW_DATA_LOW)
+		rawdata = SPRD_THM_RAW_DATA_LOW;
+	else if (rawdata > SPRD_THM_RAW_DATA_HIGH)
+		rawdata = SPRD_THM_RAW_DATA_HIGH;
+
+	/*
+	 * According to the thermal datasheet, the formula of converting
+	 * adc value to the temperature value should be:
+	 * T_final = k_cal * x - b_cal.
+	 */
+	return sen->cal_slope * rawdata - sen->cal_offset;
+}
+
+static int sprd_thm_temp_to_rawdata(int temp, struct sprd_thermal_sensor *sen)
+{
+	u32 val;
+
+	if (temp < SPRD_THM_TEMP_LOW)
+		temp = SPRD_THM_TEMP_LOW;
+	else if (temp > SPRD_THM_TEMP_HIGH)
+		temp = SPRD_THM_TEMP_HIGH;
+
+	/*
+	 * According to the thermal datasheet, the formula of converting
+	 * adc value to the temperature value should be:
+	 * T_final = k_cal * x - b_cal.
+	 */
+	val = (temp + sen->cal_offset) / sen->cal_slope;
+
+	return val >= SPRD_THM_RAW_DATA_HIGH ? (SPRD_THM_RAW_DATA_HIGH - 1) : val;
+}
+
+static int sprd_thm_read_temp(void *devdata, int *temp)
+{
+	struct sprd_thermal_sensor *sen = devdata;
+	int sensor_temp;
+	u32 data;
+
+	data = readl(sen->data->base + SPRD_THM_TEMP(sen->id)) &
+		SPRD_THM_RAW_READ_MSK;
+
+	if (sen->ready) {
+		sensor_temp = sprd_thm_rawdata_to_temp(sen, data);
+		sen->last_temp = sensor_temp;
+		*temp = sensor_temp;
+	} else {
+		/*
+		 * If the sensor is not ready, then just return last
+		 * temperature value.
+		 */
+		*temp = sen->last_temp;
+	}
+
+	return 0;
+}
+
+static const struct thermal_zone_of_device_ops sprd_thm_ops = {
+	.get_temp = sprd_thm_read_temp,
+};
+
+static int sprd_thm_poll_ready_status(struct sprd_thermal_data *thm)
+{
+	u32 val;
+	int ret;
+
+	/*
+	 * Wait for thermal ready status before configuring thermal parameters.
+	 */
+	ret = readl_poll_timeout(thm->base + SPRD_THM_CTL, val,
+				 !(val & SPRD_THM_SET_RDY_ST),
+				 SPRD_THM_RDYST_POLLING_TIME,
+				 SPRD_THM_RDYST_TIMEOUT);
+	if (ret)
+		return ret;
+
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_MON_EN,
+			     SPRD_THM_MON_EN);
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SET_RDY,
+			     SPRD_THM_SET_RDY);
+	return 0;
+}
+
+static int sprd_thm_wait_temp_ready(struct sprd_thermal_data *thm)
+{
+	u32 val;
+
+	/* Wait for first temperature data ready before reading temperature */
+	return readl_poll_timeout(thm->base + SPRD_THM_INTERNAL_STS1, val,
+				  !(val & SPRD_THM_TEMPER_RDY),
+				  SPRD_THM_TEMP_READY_POLL_TIME,
+				  SPRD_THM_TEMP_READY_TIMEOUT);
+}
+
+static int sprd_thm_set_ready(struct sprd_thermal_data *thm)
+{
+	int ret;
+
+	ret = sprd_thm_poll_ready_status(thm);
+	if (ret)
+		return ret;
+
+	/*
+	 * Clear interrupt status, enable thermal interrupt and enable thermal.
+	 */
+	writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
+	sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
+			     SPRD_THM_BIT_INT_EN, SPRD_THM_BIT_INT_EN);
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+			     SPRD_THM_EN, SPRD_THM_EN);
+	return 0;
+}
+
+static void sprd_thm_sensor_init(struct sprd_thermal_data *thm,
+				 struct sprd_thermal_sensor *sen)
+{
+	u32 otp_rawdata, hot_rawdata;
+
+	otp_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_OTP_TEMP, sen);
+	hot_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_HOT_TEMP, sen);
+
+	/* Enable the sensor' overheat temperature protection interrupt */
+	sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
+			     SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id),
+			     SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id));
+
+	/* Set the sensor' overheat and hot threshold temperature */
+	sprd_thm_update_bits(thm->base + SPRD_THM_THRES(sen->id),
+			     SPRD_THM_THRES_MASK,
+			     (otp_rawdata << SPRD_THM_OTP_TRIP_SHIFT) |
+			     hot_rawdata);
+
+	/* Enable the corresponding sensor */
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SEN(sen->id),
+			     SPRD_THM_SEN(sen->id));
+}
+
+static void sprd_thm_para_config(struct sprd_thermal_data *thm)
+{
+	/* Set the period of two valid temperature detection action */
+	sprd_thm_update_bits(thm->base + SPRD_THM_DET_PERIOD,
+			     SPRD_THM_DET_PERIOD_MASK, SPRD_THM_DET_PERIOD);
+
+	/* Set the sensors' monitor mode */
+	sprd_thm_update_bits(thm->base + SPRD_THM_MON_CTL,
+			     SPRD_THM_MON_MODE_MASK, SPRD_THM_MON_MODE);
+
+	/* Set the sensors' monitor period */
+	sprd_thm_update_bits(thm->base + SPRD_THM_MON_PERIOD,
+			     SPRD_THM_MON_PERIOD_MASK, SPRD_THM_MON_PERIOD);
+}
+
+static int sprd_thm_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *sen_child;
+	struct sprd_thermal_data *thm;
+	struct sprd_thermal_sensor *sen;
+	const struct sprd_thm_variant_data *pdata;
+	int ret, i;
+
+	pdata = of_device_get_match_data(&pdev->dev);
+	if (!pdata) {
+		dev_err(&pdev->dev, "No matching driver data found\n");
+		return -EINVAL;
+	}
+
+	thm = devm_kzalloc(&pdev->dev, sizeof(*thm), GFP_KERNEL);
+	if (!thm)
+		return -ENOMEM;
+
+	thm->var_data = pdata;
+	thm->base = devm_platform_ioremap_resource(pdev, 0);
+	if (!thm->base)
+		return -ENOMEM;
+
+	thm->nr_sensors = of_get_child_count(np);
+	if (thm->nr_sensors == 0 || thm->nr_sensors > SPRD_THM_MAX_SENSOR) {
+		dev_err(&pdev->dev, "incorrect sensor count\n");
+		return -EINVAL;
+	}
+
+	thm->clk = devm_clk_get(&pdev->dev, "enable");
+	if (IS_ERR(thm->clk)) {
+		dev_err(&pdev->dev, "failed to get enable clock\n");
+		return PTR_ERR(thm->clk);
+	}
+
+	ret = clk_prepare_enable(thm->clk);
+	if (ret)
+		return ret;
+
+	sprd_thm_para_config(thm);
+
+	ret = sprd_thm_cal_read(np, "thm_sign_cal", &thm->ratio_sign);
+	if (ret)
+		goto disable_clk;
+
+	ret = sprd_thm_cal_read(np, "thm_ratio_cal", &thm->ratio_off);
+	if (ret)
+		goto disable_clk;
+
+	for_each_child_of_node(np, sen_child) {
+		sen = devm_kzalloc(&pdev->dev, sizeof(*sen), GFP_KERNEL);
+		if (!sen) {
+			ret = -ENOMEM;
+			goto disable_clk;
+		}
+
+		sen->ready = false;
+		sen->data = thm;
+		sen->dev = &pdev->dev;
+
+		ret = of_property_read_u32(sen_child, "reg", &sen->id);
+		if (ret) {
+			dev_err(&pdev->dev, "get sensor reg failed");
+			goto disable_clk;
+		}
+
+		ret = sprd_thm_senor_calibration(sen_child, thm, sen);
+		if (ret) {
+			dev_err(&pdev->dev, "efuse cal analysis failed");
+			goto disable_clk;
+		}
+
+		sprd_thm_sensor_init(thm, sen);
+
+		sen->thmzone_dev =
+			devm_thermal_zone_of_sensor_register(sen->dev, sen->id,
+							     sen, &sprd_thm_ops);
+		if (IS_ERR(sen->thmzone_dev)) {
+			dev_err(&pdev->dev, "register thermal zone failed %d\n",
+				sen->id);
+			ret = PTR_ERR(sen->thmzone_dev);
+			goto disable_clk;
+		}
+
+		thm->sensor[sen->id] = sen;
+	}
+
+	ret = sprd_thm_set_ready(thm);
+	if (ret)
+		goto disable_clk;
+
+	ret = sprd_thm_wait_temp_ready(thm);
+	if (ret)
+		goto disable_clk;
+
+	for (i = 0; i < thm->nr_sensors; i++)
+		thm->sensor[i]->ready = true;
+
+	platform_set_drvdata(pdev, thm);
+	return 0;
+
+disable_clk:
+	clk_disable_unprepare(thm->clk);
+	return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static void sprd_thm_hw_suspend(struct sprd_thermal_data *thm)
+{
+	int i;
+
+	for (i = 0; i < thm->nr_sensors; i++) {
+		sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+				     SPRD_THM_SEN(thm->sensor[i]->id), 0);
+	}
+
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+			     SPRD_THM_EN, 0x0);
+}
+
+static int sprd_thm_suspend(struct device *dev)
+{
+	struct sprd_thermal_data *thm = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < thm->nr_sensors; i++)
+		thm->sensor[i]->ready = false;
+
+	sprd_thm_hw_suspend(thm);
+	clk_disable_unprepare(thm->clk);
+
+	return 0;
+}
+
+static int sprd_thm_hw_resume(struct sprd_thermal_data *thm)
+{
+	int ret, i;
+
+	for (i = 0; i < thm->nr_sensors; i++) {
+		sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+				     SPRD_THM_SEN(thm->sensor[i]->id),
+				     SPRD_THM_SEN(thm->sensor[i]->id));
+	}
+
+	ret = sprd_thm_poll_ready_status(thm);
+	if (ret)
+		return ret;
+
+	writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
+	sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+			     SPRD_THM_EN, SPRD_THM_EN);
+	return sprd_thm_wait_temp_ready(thm);
+}
+
+static int sprd_thm_resume(struct device *dev)
+{
+	struct sprd_thermal_data *thm = dev_get_drvdata(dev);
+	int ret, i;
+
+	ret = clk_prepare_enable(thm->clk);
+	if (ret)
+		return ret;
+
+	ret = sprd_thm_hw_resume(thm);
+	if (ret)
+		goto disable_clk;
+
+	for (i = 0; i < thm->nr_sensors; i++)
+		thm->sensor[i]->ready = true;
+
+	return 0;
+
+disable_clk:
+	clk_disable_unprepare(thm->clk);
+	return ret;
+}
+#endif
+
+static int sprd_thm_remove(struct platform_device *pdev)
+{
+	struct sprd_thermal_data *thm = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < thm->nr_sensors; i++) {
+		devm_thermal_zone_of_sensor_unregister(&pdev->dev,
+						       thm->sensor[i]->thmzone_dev);
+	}
+
+	clk_disable_unprepare(thm->clk);
+	return 0;
+}
+
+static const struct of_device_id sprd_thermal_of_match[] = {
+	{ .compatible = "sprd,ums512-thermal", .data = &ums512_data },
+	{ },
+};
+
+static const struct dev_pm_ops sprd_thermal_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(sprd_thm_suspend, sprd_thm_resume)
+};
+
+static struct platform_driver sprd_thermal_driver = {
+	.probe = sprd_thm_probe,
+	.remove = sprd_thm_remove,
+	.driver = {
+		.name = "sprd-thermal",
+		.pm = &sprd_thermal_pm_ops,
+		.of_match_table = sprd_thermal_of_match,
+	},
+};
+
+module_platform_driver(sprd_thermal_driver);
+
+MODULE_AUTHOR("Freeman Liu <freeman.liu@unisoc.com>");
+MODULE_DESCRIPTION("Spreadtrum thermal driver");
+MODULE_LICENSE("GPL v2");