Re: [PATCH v3 09/17] mmc: sdhci-msm: Fix error handling for dev_pm_opp_of_add_table()

Rajendra Nayak
2020-04-29T14:09:24Z

On 4/28/2020 11:59 PM, Ulf Hansson wrote:
> On Tue, 28 Apr 2020 at 15:39, Rajendra Nayak <rnayak@codeaurora.org> wrote:
>>
>> Even though specifying OPP's in device tree is optional, ignoring all errors
>> reported by dev_pm_opp_of_add_table() means we can't distinguish between a
>> missing OPP table and a wrong/buggy OPP table. While missing OPP table
>> (dev_pm_opp_of_add_table() returns a -ENODEV in such case) can be ignored,
>> a wrong/buggy OPP table in device tree should make the driver error out.
>>
>> while we fix that, lets also fix the variable names for opp/opp_table to
>> avoid confusion and name them opp_table/has_opp_table instead.
>>
>> Suggested-by: Matthias Kaehlcke <matthias@chromium.org>
>> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
>> Cc: Ulf Hansson <ulf.hansson@linaro.org>
>> Cc: Pradeep P V K <ppvk@codeaurora.org>
>> Cc: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
>> Cc: linux-mmc@vger.kernel.org
>
> Is this a standalone patch that I queue up via my mmc tree?

Hi Ulf, yes, its a standalone patch which applies on top of the one
you already have in your tree. No other dependencies.

>
> Kind regards
> Uffe
>
>> ---
>> drivers/mmc/host/sdhci-msm.c | 27 ++++++++++++++++-----------
>> 1 file changed, 16 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
>> index 8a055dd..97758fa 100644
>> --- a/drivers/mmc/host/sdhci-msm.c
>> +++ b/drivers/mmc/host/sdhci-msm.c
>> @@ -244,8 +244,8 @@ struct sdhci_msm_host {
>> struct clk_bulk_data bulk_clks[4]; /* core, iface, cal, sleep clocks */
>> unsigned long clk_rate;
>> struct mmc_host *mmc;
>> - struct opp_table *opp;
>> - bool opp_table;
>> + struct opp_table *opp_table;
>> + bool has_opp_table;
>> bool use_14lpp_dll_reset;
>> bool tuning_done;
>> bool calibration_done;
>> @@ -1967,15 +1967,20 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>> }
>> msm_host->bulk_clks[0].clk = clk;
>>
>> - msm_host->opp = dev_pm_opp_set_clkname(&pdev->dev, "core");
>> - if (IS_ERR(msm_host->opp)) {
>> - ret = PTR_ERR(msm_host->opp);
>> + msm_host->opp_table = dev_pm_opp_set_clkname(&pdev->dev, "core");
>> + if (IS_ERR(msm_host->opp_table)) {
>> + ret = PTR_ERR(msm_host->opp_table);
>> goto bus_clk_disable;
>> }
>>
>> /* OPP table is optional */
>> - if (!dev_pm_opp_of_add_table(&pdev->dev))
>> - msm_host->opp_table = true;
>> + ret = dev_pm_opp_of_add_table(&pdev->dev);
>> + if (!ret) {
>> + msm_host->has_opp_table = true;
>> + } else if (ret != -ENODEV) {
>> + dev_err(&pdev->dev, "Invalid OPP table in Device tree\n");
>> + goto opp_cleanup;
>> + }
>>
>> /* Vote for maximum clock rate for maximum performance */
>> ret = dev_pm_opp_set_rate(&pdev->dev, INT_MAX);
>> @@ -2133,9 +2138,9 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>> clk_bulk_disable_unprepare(ARRAY_SIZE(msm_host->bulk_clks),
>> msm_host->bulk_clks);
>> opp_cleanup:
>> - if (msm_host->opp_table)
>> + if (msm_host->has_opp_table)
>> dev_pm_opp_of_remove_table(&pdev->dev);
>> - dev_pm_opp_put_clkname(msm_host->opp);
>> + dev_pm_opp_put_clkname(msm_host->opp_table);
>> bus_clk_disable:
>> if (!IS_ERR(msm_host->bus_clk))
>> clk_disable_unprepare(msm_host->bus_clk);
>> @@ -2154,9 +2159,9 @@ static int sdhci_msm_remove(struct platform_device *pdev)
>>
>> sdhci_remove_host(host, dead);
>>
>> - if (msm_host->opp_table)
>> + if (msm_host->has_opp_table)
>> dev_pm_opp_of_remove_table(&pdev->dev);
>> - dev_pm_opp_put_clkname(msm_host->opp);
>> + dev_pm_opp_put_clkname(msm_host->opp_table);
>> pm_runtime_get_sync(&pdev->dev);
>> pm_runtime_disable(&pdev->dev);
>> pm_runtime_put_noidle(&pdev->dev);
>> --
>> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
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