From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Mon, 14 Sep 2020 14:17:54 +0000 Subject: Re: [PATCH] PM / devfreq: tegra30: disable clock on error in probe Message-Id: <20200914141754.GB18329@kadam> List-Id: References: <20200908072557.GC294938@mwanda> <2ceb045a-ebac-58d7-0250-4ea39d711ce8@samsung.com> <44560522-f04e-ade5-2e02-9df56a6f79ba@gmail.com> In-Reply-To: <44560522-f04e-ade5-2e02-9df56a6f79ba@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: Dmitry Osipenko Cc: Chanwoo Choi , MyungJoo Ham , Kyungmin Park , Thierry Reding , Jonathan Hunter , linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org, kernel-janitors@vger.kernel.org On Mon, Sep 14, 2020 at 04:56:26PM +0300, Dmitry Osipenko wrote: > 14.09.2020 10:09, Chanwoo Choi пишет: > > Hi, > > > > On 9/8/20 4:25 PM, Dan Carpenter wrote: > >> This error path needs to call clk_disable_unprepare(). > >> > >> Fixes: 7296443b900e ("PM / devfreq: tegra30: Handle possible round-rate error") > >> Signed-off-by: Dan Carpenter > >> --- > >> --- > >> drivers/devfreq/tegra30-devfreq.c | 4 +++- > >> 1 file changed, 3 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c > >> index e94a27804c20..dedd39de7367 100644 > >> --- a/drivers/devfreq/tegra30-devfreq.c > >> +++ b/drivers/devfreq/tegra30-devfreq.c > >> @@ -836,7 +836,8 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > >> rate = clk_round_rate(tegra->emc_clock, ULONG_MAX); > >> if (rate < 0) { > >> dev_err(&pdev->dev, "Failed to round clock rate: %ld\n", rate); > >> - return rate; > >> + err = rate; > >> + goto disable_clk; > >> } > >> > >> tegra->max_freq = rate / KHZ; > >> @@ -897,6 +898,7 @@ static int tegra_devfreq_probe(struct platform_device *pdev) > >> dev_pm_opp_remove_all_dynamic(&pdev->dev); > >> > >> reset_control_reset(tegra->reset); > >> +disable_clk: > >> clk_disable_unprepare(tegra->clock); > > > > Is it doesn't need to reset with reset_contrl_reset()? > > Hello, Chanwoo! > > It's reset just before the clk_round_rate() invocation, hence there > shouldn't be a need to reset it second time. Ah... I was looking the wrong code. Plus I don't really know this code very well. If clk_prepare_enable() fails, then I would have assumed we need to call reset_control_deassert(). I would have assumed the reset_control_assert() and _deassert() functions were paired. So what I'm suggesting is something like the following: (I'll resend this if it's correct). [PATCH] PM / devfreq: tegra30: Add missing reset_control_deassert() If clk_prepare_enable() fails then probe needs to call the reset_control_deassert() function. Fixes: 6234f38016ad ("PM / devfreq: tegra: add devfreq driver for Tegra Activity Monitor") Signed-off-by: Dan Carpenter --- drivers/devfreq/tegra30-devfreq.c | 1 + 1 file changed, 1 insertions(+), 0 deletion(-) diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c index e94a27804c20..ce217aba7b9d 100644 --- a/drivers/devfreq/tegra30-devfreq.c +++ b/drivers/devfreq/tegra30-devfreq.c @@ -828,6 +828,7 @@ static int tegra_devfreq_probe(struct platform_device *pdev) if (err) { dev_err(&pdev->dev, "Failed to prepare and enable ACTMON clock\n"); + reset_control_deassert(tegra->reset); return err; }