[PATCH 3/6] drivers/thermal/exynos: check IS_ERR(data->clk) consistently
Sam Protsenko
semen.protsenko at linaro.org
Mon Jul 22 14:03:24 PDT 2024
On Fri, Jul 19, 2024 at 7:10 AM Mateusz Majewski
<m.majewski2 at samsung.com> wrote:
>
> This will be needed for Exynos 850 support, which does not require this
> clock.
>
> It would also be possible to set data->clk to NULL instead, but doing it
> like this is consistent with what we do with data->clk_sec.
>
> Signed-off-by: Mateusz Majewski <m.majewski2 at samsung.com>
> ---
> drivers/thermal/samsung/exynos_tmu.c | 58 ++++++++++++++++++----------
> 1 file changed, 38 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
> index 61606a9b9a00..f0de72a62fd7 100644
> --- a/drivers/thermal/samsung/exynos_tmu.c
> +++ b/drivers/thermal/samsung/exynos_tmu.c
> @@ -257,7 +257,8 @@ static int exynos_tmu_initialize(struct platform_device *pdev)
> int ret = 0;
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
Hmm, it looks like it's better to rework this clock obtaining using
devm_clk_get_optional() API, or even devm_clk_get_optional_prepared()
in this case. It'll simplify its further usage, i.e. it'll be possible
to just call clk_enable() without checking the clock with IS_ERR()
each time. You can check these drivers for pointers on optional API
usage:
- drivers/i2c/busses/i2c-exynos5.c
- drivers/watchdog/s3c2410_wdt.c
Also, if it's only optional for Exynos850 (and not optional for other
chips), maybe it would be a good idea to use *_optional_* API only for
Exynos850 case, so that the driver's behavior for those chips stays
unchanged.
Btw, from the downstream kernel code [1] I can see that the only TMU
clock present in Exynos850 is
GOUT_BLK_PERI_UID_BUSIF_TMU_IPCLKPORT_PCLK (which I was able to
confirm in TRM). But it's not enabled in clk-exynos850.c driver right
now. Do you want me by chance to send the patch adding it?
[1] https://gitlab.com/Linaro/96boards/e850-96/kernel/-/blob/android-exynos-5.10-linaro/drivers/soc/samsung/cal-if/s5e3830/cmucal-node.c?ref_type=heads#L1196
> if (!IS_ERR(data->clk_sec))
> clk_enable(data->clk_sec);
>
> @@ -271,7 +272,8 @@ static int exynos_tmu_initialize(struct platform_device *pdev)
>
> if (!IS_ERR(data->clk_sec))
> clk_disable(data->clk_sec);
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
>
> return ret;
> @@ -295,11 +297,13 @@ static int exynos_thermal_zone_configure(struct platform_device *pdev)
> }
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
>
> data->tmu_set_crit_temp(data, temp / MCELSIUS);
>
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
>
> return 0;
> @@ -328,10 +332,12 @@ static void exynos_tmu_control(struct platform_device *pdev, bool on)
> struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
> data->tmu_control(pdev, on);
> data->enabled = on;
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
> }
>
> @@ -648,7 +654,8 @@ static int exynos_get_temp(struct thermal_zone_device *tz, int *temp)
> return -EAGAIN;
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
>
> value = data->tmu_read(data);
> if (value < 0)
> @@ -656,7 +663,8 @@ static int exynos_get_temp(struct thermal_zone_device *tz, int *temp)
> else
> *temp = code_to_temp(data, value) * MCELSIUS;
>
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
>
> return ret;
> @@ -723,9 +731,11 @@ static int exynos_tmu_set_emulation(struct thermal_zone_device *tz, int temp)
> goto out;
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
> data->tmu_set_emulation(data, temp);
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
> return 0;
> out:
> @@ -763,12 +773,14 @@ static irqreturn_t exynos_tmu_threaded_irq(int irq, void *id)
> thermal_zone_device_update(data->tzd, THERMAL_EVENT_UNSPECIFIED);
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
>
> /* TODO: take action based on particular interrupt */
> data->tmu_clear_irqs(data);
>
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
>
> return IRQ_HANDLED;
> @@ -979,7 +991,8 @@ static int exynos_set_trips(struct thermal_zone_device *tz, int low, int high)
> struct exynos_tmu_data *data = thermal_zone_device_priv(tz);
>
> mutex_lock(&data->lock);
> - clk_enable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_enable(data->clk);
>
> if (low > INT_MIN)
> data->tmu_set_low_temp(data, low / MCELSIUS);
> @@ -990,7 +1003,8 @@ static int exynos_set_trips(struct thermal_zone_device *tz, int low, int high)
> else
> data->tmu_disable_high(data);
>
> - clk_disable(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_disable(data->clk);
> mutex_unlock(&data->lock);
>
> return 0;
> @@ -1053,10 +1067,12 @@ static int exynos_tmu_probe(struct platform_device *pdev)
> }
> }
>
> - ret = clk_prepare(data->clk);
> - if (ret) {
> - dev_err(dev, "Failed to get clock\n");
> - goto err_clk_sec;
> + if (!IS_ERR(data->clk)) {
> + ret = clk_prepare(data->clk);
> + if (ret) {
> + dev_err(dev, "Failed to get clock\n");
> + goto err_clk_sec;
> + }
> }
>
> switch (data->soc) {
> @@ -1113,7 +1129,8 @@ static int exynos_tmu_probe(struct platform_device *pdev)
> err_sclk:
> clk_disable_unprepare(data->sclk);
> err_clk:
> - clk_unprepare(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_unprepare(data->clk);
> err_clk_sec:
> if (!IS_ERR(data->clk_sec))
> clk_unprepare(data->clk_sec);
> @@ -1127,7 +1144,8 @@ static void exynos_tmu_remove(struct platform_device *pdev)
> exynos_tmu_control(pdev, false);
>
> clk_disable_unprepare(data->sclk);
> - clk_unprepare(data->clk);
> + if (!IS_ERR(data->clk))
> + clk_unprepare(data->clk);
> if (!IS_ERR(data->clk_sec))
> clk_unprepare(data->clk_sec);
> }
> --
> 2.45.1
>
>
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