On 05/06/2020 05:50, Michael Kao wrote:
> On Fri, 2020-05-22 at 17:36 +0200, Daniel Lezcano wrote:
>> On 23/03/2020 13:15, Michael Kao wrote:
>>> From: "michael.kao" <michael.kao@xxxxxxxxxxxx>
>>>
>>> The driver of thermal and svs will use the
>>> same register for the project which should select
>>> bank before reading sensor value.
>>
>> Here there is a design problem AFAICT. The sensor should not be using
>> external locks.
>>
> The PTPCORESEL is a common register used by svs and thermal.
> The thermal need to ensure PTPCORESEL register will not be changed by
> svs when thermal switch bank to read raw data of temperature.
> So we use svs_lock to make sure there is no conflict between the two
> drivers.
Why not use regmap ?
>>> Signed-off-by: Michael Kao <michael.kao@xxxxxxxxxxxx>
>>> ---
>>> drivers/thermal/mtk_thermal.c | 9 ++++-----
>>> 1 file changed, 4 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/thermal/mtk_thermal.c b/drivers/thermal/mtk_thermal.c
>>> index 9eaca432920e..594ad4f0f8cd 100644
>>> --- a/drivers/thermal/mtk_thermal.c
>>> +++ b/drivers/thermal/mtk_thermal.c
>>> @@ -22,6 +22,7 @@
>>> #include <linux/thermal.h>
>>> #include <linux/reset.h>
>>> #include <linux/types.h>
>>> +#include <linux/power/mtk_svs.h>
>>>
>>> /* AUXADC Registers */
>>> #define AUXADC_CON1_SET_V 0x008
>>> @@ -262,7 +263,7 @@ struct mtk_thermal {
>>> struct clk *clk_peri_therm;
>>> struct clk *clk_auxadc;
>>> /* lock: for getting and putting banks */
>>> - struct mutex lock;
>>> + unsigned long flags;
>>>
>>> /* Calibration values */
>>> s32 adc_ge;
>>> @@ -561,7 +562,7 @@ static void mtk_thermal_get_bank(struct mtk_thermal_bank *bank)
>>> u32 val;
>>>
>>> if (mt->conf->need_switch_bank) {
>>> - mutex_lock(&mt->lock);
>>> + mt->flags = claim_mtk_svs_lock();
>>>
>>> val = readl(mt->thermal_base + PTPCORESEL);
>>> val &= ~0xf;
>>> @@ -581,7 +582,7 @@ static void mtk_thermal_put_bank(struct mtk_thermal_bank *bank)
>>> struct mtk_thermal *mt = bank->mt;
>>>
>>> if (mt->conf->need_switch_bank)
>>> - mutex_unlock(&mt->lock);
>>> + release_mtk_svs_lock(mt->flags);
>>> }
>>>
>>> /**
>>> @@ -938,8 +939,6 @@ static int mtk_thermal_probe(struct platform_device *pdev)
>>> if (ret)
>>> return ret;
>>>
>>> - mutex_init(&mt->lock);
>>> -
>>> mt->dev = &pdev->dev;
>>>
>>> auxadc = of_parse_phandle(np, "mediatek,auxadc", 0);
>>>
>>
>>
>
--
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