On 21.08.2015 05:03, Heiner Kallweit wrote:
> Extend the driver to make full use of runtime PM autosuspend.
> Before only the SPI core was instructed to use autosuspend
> by setting master->auto_runtime_pm. Nevertheless due to the missing
> pm_runtime_use_autosuspend call autosuspend wasn't active.
> 
> Signed-off-by: Heiner Kallweit <[email protected]>
> ---
> Changed:
> - Let driver autosuspend also after leaving s3c64xx_spi_setup
> - Enable runtime PM earlier in s3c64xx_spi_probe and prevent
>   suspending in the relevant part of probe
> 
>  drivers/spi/spi-s3c64xx.c | 32 +++++++++++++++++++++-----------
>  1 file changed, 21 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index 8a6ab88..edeac06 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -32,6 +32,7 @@
>  #define MAX_SPI_PORTS                6
>  #define S3C64XX_SPI_QUIRK_POLL               (1 << 0)
>  #define S3C64XX_SPI_QUIRK_CS_AUTO    (1 << 1)
> +#define AUTOSUSPEND_TIMEOUT  2000
>  
>  /* Registers and bit-fields */
>  
> @@ -859,13 +860,15 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
>               }
>       }
>  
> -     pm_runtime_put(&sdd->pdev->dev);
> +     pm_runtime_mark_last_busy(&sdd->pdev->dev);
> +     pm_runtime_put_autosuspend(&sdd->pdev->dev);
>       if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
>               writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + 
> S3C64XX_SPI_SLAVE_SEL);
>       return 0;
>  
>  setup_exit:
> -     pm_runtime_put(&sdd->pdev->dev);
> +     pm_runtime_mark_last_busy(&sdd->pdev->dev);
> +     pm_runtime_put_autosuspend(&sdd->pdev->dev);
>       /* setup() returns with device de-selected */
>       if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
>               writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + 
> S3C64XX_SPI_SLAVE_SEL);
> @@ -1133,18 +1136,24 @@ static int s3c64xx_spi_probe(struct platform_device 
> *pdev)
>               goto err0;
>       }
>  
> +     pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
> +     pm_runtime_use_autosuspend(&pdev->dev);
> +     pm_runtime_set_active(&pdev->dev);
> +     pm_runtime_enable(&pdev->dev);

I think you should not enable the PM runtime too early. The PM runtime
callbacks can be fired now but driver did not get references to clocks yet.

Best regards,
Krzysztof

> +     pm_runtime_get_noresume(&pdev->dev);
> +
>       /* Setup clocks */
>       sdd->clk = devm_clk_get(&pdev->dev, "spi");
>       if (IS_ERR(sdd->clk)) {
>               dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
>               ret = PTR_ERR(sdd->clk);
> -             goto err0;
> +             goto err1;
>       }
>  
>       if (clk_prepare_enable(sdd->clk)) {
>               dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
>               ret = -EBUSY;
> -             goto err0;
> +             goto err1;
>       }
>  
>       sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
> @@ -1180,13 +1189,10 @@ static int s3c64xx_spi_probe(struct platform_device 
> *pdev)
>              S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
>              sdd->regs + S3C64XX_SPI_INT_EN);
>  
> -     pm_runtime_set_active(&pdev->dev);
> -     pm_runtime_enable(&pdev->dev);
> -
>       ret = devm_spi_register_master(&pdev->dev, master);
>       if (ret != 0) {
>               dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
> -             goto err4;
> +             goto err3;
>       }
>  
>       dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with 
> %d Slaves attached\n",
> @@ -1195,15 +1201,19 @@ static int s3c64xx_spi_probe(struct platform_device 
> *pdev)
>                                       mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1,
>                                       sdd->rx_dma.dmach, sdd->tx_dma.dmach);
>  
> +     pm_runtime_mark_last_busy(&pdev->dev);
> +     pm_runtime_put_autosuspend(&pdev->dev);
> +
>       return 0;
>  
> -err4:
> -     pm_runtime_disable(&pdev->dev);
> -     pm_runtime_set_suspended(&pdev->dev);
>  err3:
>       clk_disable_unprepare(sdd->src_clk);
>  err2:
>       clk_disable_unprepare(sdd->clk);
> +err1:
> +     pm_runtime_put_noidle(&pdev->dev);
> +     pm_runtime_disable(&pdev->dev);
> +     pm_runtime_set_suspended(&pdev->dev);
>  err0:
>       spi_master_put(master);
>  
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to