Re: [PATCH v7 6/9] drm/mediatek: add dsi interrupt control

[CK Hu <ck.hu@mediatek.com>]

Hi, YT:

On Fri, 2016-09-02 at 19:24 +0800, YT Shen wrote:
> From: shaoming chen <shaoming.chen@mediatek.com>
> 
> add dsi interrupt control
> 
> Signed-off-by: shaoming chen <shaoming.chen@mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 76 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 76 insertions(+)
> 

[snip...]

>  
> +static wait_queue_head_t _dsi_irq_wait_queue;

I think it's better to move this global variable into platform driver
data. Maybe one day you have two dsi device and one global variable is
not enough.

> +

[snip...]

> +
> +static irqreturn_t mtk_dsi_irq(int irq, void *dev_id)
> +{
> +	struct mtk_dsi *dsi = dev_id;
> +	u32 status, tmp;
> +	u32 flag = LPRX_RD_RDY_INT_FLAG | CMD_DONE_INT_FLAG | VM_DONE_INT_FLAG;
> +
> +	status = readl(dsi->regs + DSI_INTSTA);

If you define as

status = readl(dsi->regs + DSI_INTSTA) & flag;

You can remove 'flag' in below statements and reduce code size.

> +
> +	if (status & flag) {
> +		do {
> +			mtk_dsi_mask(dsi, DSI_RACK, RACK, RACK);
> +			tmp = readl(dsi->regs + DSI_INTSTA);
> +		} while (tmp & DSI_BUSY);
> +
> +		mtk_dsi_mask(dsi, DSI_INTSTA, status & flag, 0);
> +		mtk_dsi_irq_data_set(dsi, status & flag);
> +		wake_up_interruptible(&_dsi_irq_wait_queue);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +

[snip...]

>  
> @@ -869,8 +926,27 @@ static int mtk_dsi_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> +	irq_num = platform_get_irq(pdev, 0);
> +	if (irq_num < 0) {
> +		dev_err(&pdev->dev, "failed to request dsi irq resource\n");
> +		return -EPROBE_DEFER;
> +	}
> +
> +	irq_set_status_flags(irq_num, IRQ_TYPE_LEVEL_LOW);
> +	ret = devm_request_irq(&pdev->dev, irq_num, mtk_dsi_irq,
> +			       IRQF_TRIGGER_LOW, dev_name(&pdev->dev), dsi);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to request mediatek dsi irq\n");
> +		return -EPROBE_DEFER;
> +	}
> +
> +	dsi->irq_data = 0;

You use devm_kzalloc() to allocate 'dsi', so this statement is
redundant.

> +	dev_info(dev, "dsi irq num is 0x%x\n", irq_num);
> +
>  	platform_set_drvdata(pdev, dsi);
>  
> +	init_waitqueue_head(&_dsi_irq_wait_queue);
> +
>  	return component_add(&pdev->dev, &mtk_dsi_component_ops);
>  }


Regards,
CK