Re: [PATCH] devfreq: rk3399_dmc: Fix duplicated opp table on reload.

Chanwoo Choi
2018-06-17T03:23:18Z

Hi Enric,

2018-06-16 0:12 GMT+09:00 Enric Balletbo i Serra <enric.balletbo@collabora.com>:
> The opp table is not removed when the driver is unloaded neither when
> there is an error within probe, so if the driver is reloaded the opp
> core shows the following warning:
>
> rk3399-dmc-freq dmc: _opp_add: duplicate OPPs detected. Existing: freq:
> 200000000, volt: 900000, enabled: 1. New: freq: 200000000,
> volt: 900000, enabled: 1
> rk3399-dmc-freq dmc: _opp_add: duplicate OPPs detected. Existing: freq:
> 400000000, volt: 900000, enabled: 1. New: freq: 400000000,
> volt: 900000, enabled: 1
> rk3399-dmc-freq dmc: _opp_add: duplicate OPPs detected. Existing: freq:
> 666000000, volt: 900000, enabled: 1. New: freq: 666000000,
> volt: 900000, enabled: 1
> rk3399-dmc-freq dmc: _opp_add: duplicate OPPs detected. Existing: freq:
> 800000000, volt: 900000, enabled: 1. New: freq: 800000000,
> volt: 900000, enabled: 1
> rk3399-dmc-freq dmc: _opp_add: duplicate OPPs detected. Existing: freq:
> 928000000, volt: 900000, enabled: 1. New: freq: 928000000,
> volt: 900000, enabled: 1
>
> This patch fixes the error path in the probe function and adds a .remove
> function to properly cleanup the opp table on unloading.
>
> Fixes: 5a893e31a636c (PM / devfreq: rockchip: add devfreq driver for rk3399 dmc)
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> ---
>
> drivers/devfreq/rk3399_dmc.c | 31 +++++++++++++++++++++++++++----
> 1 file changed, 27 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
> index d5c03e5abe13..e795ad2b3f6b 100644
> --- a/drivers/devfreq/rk3399_dmc.c
> +++ b/drivers/devfreq/rk3399_dmc.c
> @@ -375,8 +375,10 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
> data->rate = clk_get_rate(data->dmc_clk);
>
> opp = devfreq_recommended_opp(dev, &data->rate, 0);
> - if (IS_ERR(opp))
> - return PTR_ERR(opp);
> + if (IS_ERR(opp)) {
> + ret = PTR_ERR(opp);
> + goto err_free_opp;
> + }
>
> data->rate = dev_pm_opp_get_freq(opp);
> data->volt = dev_pm_opp_get_voltage(opp);
> @@ -388,13 +390,33 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
> &rk3399_devfreq_dmc_profile,
> DEVFREQ_GOV_SIMPLE_ONDEMAND,
> &data->ondemand_data);
> - if (IS_ERR(data->devfreq))
> - return PTR_ERR(data->devfreq);
> + if (IS_ERR(data->devfreq)) {
> + ret = PTR_ERR(data->devfreq);
> + goto err_free_opp;
> + }
> +
> devm_devfreq_register_opp_notifier(dev, data->devfreq);
>
> data->dev = dev;
> platform_set_drvdata(pdev, data);
>
> + return 0;

It looks strange. Because rk3399_dmcfreq_probe() already include
'return 0' when success.
What is the base commit of this patch?

[snip]

Anyway, if probe fail, device driver have to remove registered OPP table.
Looks good to me.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

--
Best Regards,
Chanwoo Choi
Samsung Electronics