[PATCH] [media] at91: add Atmel Image Sensor Interface (ISI) support

[linux@arm.linux.org.uk (Russell King - ARM Linux)]

On Thu, May 12, 2011 at 03:42:18PM +0800, Josh Wu wrote:
> This patch is to enable Atmel Image Sensor Interface (ISI) driver support. 
> - Using soc-camera framework with videobuf2 dma-contig allocator
> - Supporting video streaming of YUV packed format
> - Tested on AT91SAM9M10G45-EK with OV2640

A few more points...

> +static int __init atmel_isi_probe(struct platform_device *pdev)

Should be __devinit otherwise you'll have section errors.

> +{
> +	unsigned int irq;
> +	struct atmel_isi *isi;
> +	struct clk *pclk;
> +	struct resource *regs;
> +	int ret;
> +	struct device *dev = &pdev->dev;
> +	struct isi_platform_data *pdata;
> +	struct soc_camera_host *soc_host;
> +
> +	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!regs)
> +		return -ENXIO;
> +
> +	pclk = clk_get(&pdev->dev, "isi_clk");
> +	if (IS_ERR(pclk))
> +		return PTR_ERR(pclk);
> +
> +	clk_enable(pclk);

Return value of clk_enable() should be checked.

> +
> +	isi = kzalloc(sizeof(struct atmel_isi), GFP_KERNEL);
> +	if (!isi) {
> +		ret = -ENOMEM;
> +		dev_err(&pdev->dev, "can't allocate interface!\n");
> +		goto err_alloc_isi;
> +	}
> +
> +	isi->pclk = pclk;
> +
> +	spin_lock_init(&isi->lock);
> +	init_waitqueue_head(&isi->capture_wq);
> +
> +	isi->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev);
> +	if (IS_ERR(isi->alloc_ctx)) {
> +		ret = PTR_ERR(isi->alloc_ctx);
> +		goto err_alloc_isi;
> +	}
> +
> +	isi->regs = ioremap(regs->start, resource_size(regs));
> +	if (!isi->regs) {
> +		ret = -ENOMEM;
> +		goto err_ioremap;
> +	}
> +
> +	if (dev->platform_data)
> +		pdata = (struct isi_platform_data *) dev->platform_data;
> +	else {
> +		static struct isi_platform_data isi_default_data = {
> +			.frate		= 0,
> +			.has_emb_sync	= 0,
> +			.emb_crc_sync	= 0,
> +			.hsync_act_low	= 0,
> +			.vsync_act_low	= 0,
> +			.pclk_act_falling = 0,
> +			.isi_full_mode	= 1,
> +			/* to use codec and preview path simultaneously */
> +			.flags = ISI_DATAWIDTH_8 |
> +				ISI_DATAWIDTH_10,
> +		};
> +		dev_info(&pdev->dev,
> +			"No config available using default values\n");
> +		pdata = &isi_default_data;
> +	}
> +
> +	isi->pdata = pdata;
> +	isi->platform_flags = pdata->flags;
> +	if (isi->platform_flags == 0)
> +		isi->platform_flags = ISI_DATAWIDTH_8;
> +
> +	isi_writel(isi, V2_CTRL, ISI_BIT(V2_DIS));
> +	/* Check if module disable */
> +	while (isi_readl(isi, V2_STATUS) & ISI_BIT(V2_DIS))
> +		cpu_relax();
> +
> +	irq = platform_get_irq(pdev, 0);

This should also be checked.