Re: [PATCH 08/13] thermal/drivers/hisi: Fix configuration register setting

Leo Yan
2017-09-02T02:54:37Z

On Wed, Aug 30, 2017 at 10:47:32AM +0200, Daniel Lezcano wrote:
> The TEMP0_CFG configuration register contains different field to set up the
> temperature controller. However in the code, nothing prevents a setup to
> overwrite the previous one: eg. writing the hdak value overwrites the sensor
> selection, the sensor selection overwrites the hdak value.
>
> In order to prevent such thing, use a regmap-like mechanism by reading the
> value before, set the corresponding bits and write the result.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
> drivers/thermal/hisi_thermal.c | 30 +++++++++++++++++++++++++-----
> 1 file changed, 25 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/thermal/hisi_thermal.c b/drivers/thermal/hisi_thermal.c
> index d77a938..3e03908 100644
> --- a/drivers/thermal/hisi_thermal.c
> +++ b/drivers/thermal/hisi_thermal.c
> @@ -132,19 +132,39 @@ static inline void hisi_thermal_enable(void __iomem *addr, int value)
> writel(value, addr + TEMP0_EN);
> }
>
> -static inline void hisi_thermal_sensor_select(void __iomem *addr, int sensor)
> +static inline int hisi_thermal_get_temperature(void __iomem *addr)
> {
> - writel((sensor << 12), addr + TEMP0_CFG);
> + return hisi_thermal_step_to_temp(readl(addr + TEMP0_VALUE));
> }
>
> -static inline int hisi_thermal_get_temperature(void __iomem *addr)
> +/*
> + * Temperature configuration register - Sensor selection
> + *
> + * Bits [19:12]
> + *
> + * 0x0: local sensor (default)
> + * 0x1: remote sensor 1 (ACPU cluster 1)
> + * 0x2: remote sensor 2 (ACPU cluster 0)
> + * 0x3: remote sensor 3 (G3D)
> + */
> +static inline void hisi_thermal_sensor_select(void __iomem *addr, int sensor)
> {
> - return hisi_thermal_step_to_temp(readl(addr + TEMP0_VALUE));
> + writel(readl(addr + TEMP0_CFG) | (sensor << 12), addr + TEMP0_CFG);

nitpick: maybe it's better to firstly clear related bits and then set
value?

> }
>
> +/*
> + * Temperature configuration register - Hdak conversion polling interval
> + *
> + * Bits [5:4]
> + *
> + * 0x0 : 0.768 ms
> + * 0x1 : 6.144 ms
> + * 0x2 : 49.152 ms
> + * 0x3 : 393.216 ms
> + */
> static inline void hisi_thermal_hdak_set(void __iomem *addr, int value)
> {
> - writel(value, addr + TEMP0_CFG);
> + writel(readl(addr + TEMP0_CFG) | (value << 4), addr + TEMP0_CFG);

Ditto.

> }
>
> static long hisi_thermal_get_sensor_temp(struct hisi_thermal_data *data,
> --
> 2.7.4
>