On Fri, 23 Aug 2024 18:19:28 +0800
Liao Yuanhong <liaoyuanhong@xxxxxxxx> wrote:
> Use devm_clk_get_enabled() instead of clk functions in at_hdmac.
Doesn't this stop the clock being turned of in suspend?
Or is there some magic handling that which I'm not aware of?
>
> Signed-off-by: Liao Yuanhong <liaoyuanhong@xxxxxxxx>
> ---
> drivers/dma/at_hdmac.c | 22 +++++-----------------
> 1 file changed, 5 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
> index 40052d1bd0b5..b1e10541cb12 100644
> --- a/drivers/dma/at_hdmac.c
> +++ b/drivers/dma/at_hdmac.c
> @@ -337,7 +337,6 @@ static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
> * struct at_dma - internal representation of an Atmel HDMA Controller
> * @dma_device: dmaengine dma_device object members
> * @regs: memory mapped register base
> - * @clk: dma controller clock
> * @save_imr: interrupt mask register that is saved on suspend/resume cycle
> * @all_chan_mask: all channels availlable in a mask
> * @lli_pool: hw lli table
> @@ -347,7 +346,6 @@ static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
> struct at_dma {
> struct dma_device dma_device;
> void __iomem *regs;
> - struct clk *clk;
> u32 save_imr;
>
> u8 all_chan_mask;
> @@ -1942,6 +1940,7 @@ static int __init at_dma_probe(struct platform_device *pdev)
> int err;
> int i;
> const struct at_dma_platform_data *plat_dat;
> + struct clk *clk;
>
> /* setup platform data for each SoC */
> dma_cap_set(DMA_MEMCPY, at91sam9rl_config.cap_mask);
> @@ -1975,20 +1974,16 @@ static int __init at_dma_probe(struct platform_device *pdev)
> atdma->dma_device.cap_mask = plat_dat->cap_mask;
> atdma->all_chan_mask = (1 << plat_dat->nr_channels) - 1;
>
> - atdma->clk = devm_clk_get(&pdev->dev, "dma_clk");
> - if (IS_ERR(atdma->clk))
> - return PTR_ERR(atdma->clk);
> -
> - err = clk_prepare_enable(atdma->clk);
> - if (err)
> - return err;
> + clk = devm_clk_get_enabled(&pdev->dev, "dma_clk");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
>
> /* force dma off, just in case */
> at_dma_off(atdma);
>
> err = request_irq(irq, at_dma_interrupt, 0, "at_hdmac", atdma);
> if (err)
> - goto err_irq;
> + return err;
>
> platform_set_drvdata(pdev, atdma);
>
> @@ -2105,8 +2100,6 @@ static int __init at_dma_probe(struct platform_device *pdev)
> dma_pool_destroy(atdma->lli_pool);
> err_desc_pool_create:
> free_irq(platform_get_irq(pdev, 0), atdma);
> -err_irq:
> - clk_disable_unprepare(atdma->clk);
> return err;
> }
>
> @@ -2130,8 +2123,6 @@ static void at_dma_remove(struct platform_device *pdev)
> atc_disable_chan_irq(atdma, chan->chan_id);
> list_del(&chan->device_node);
> }
> -
> - clk_disable_unprepare(atdma->clk);
> }
>
> static void at_dma_shutdown(struct platform_device *pdev)
> @@ -2139,7 +2130,6 @@ static void at_dma_shutdown(struct platform_device *pdev)
> struct at_dma *atdma = platform_get_drvdata(pdev);
>
> at_dma_off(platform_get_drvdata(pdev));
> - clk_disable_unprepare(atdma->clk);
> }
>
> static int at_dma_prepare(struct device *dev)
> @@ -2194,7 +2184,6 @@ static int at_dma_suspend_noirq(struct device *dev)
>
> /* disable DMA controller */
> at_dma_off(atdma);
> - clk_disable_unprepare(atdma->clk);
> return 0;
> }
>
> @@ -2223,7 +2212,6 @@ static int at_dma_resume_noirq(struct device *dev)
> struct dma_chan *chan, *_chan;
>
> /* bring back DMA controller */
> - clk_prepare_enable(atdma->clk);
> dma_writel(atdma, EN, AT_DMA_ENABLE);
>
> /* clear any pending interrupt */
