[PATCH] macb: detect IP version to determin if we are on at91 or avr32
Russell King - ARM Linux
linux at arm.linux.org.uk
Mon Mar 14 06:15:13 EDT 2011
On Fri, Mar 11, 2011 at 06:13:05PM +0100, Jean-Christophe PLAGNIOL-VILLARD wrote:
> + if (macb_is_at91(bp)) {
> + bp->pclk = clk_get(&pdev->dev, "macb_clk");
> + if (IS_ERR(bp->pclk)) {
> + dev_err(&pdev->dev, "failed to get macb_clk\n");
> + goto err_out_free_dev;
> + }
> + clk_enable(bp->pclk);
> + } else {
> + bp->pclk = clk_get(&pdev->dev, "pclk");
> + if (IS_ERR(bp->pclk)) {
> + dev_err(&pdev->dev, "failed to get pclk\n");
> + goto err_out_free_dev;
> + }
> + bp->hclk = clk_get(&pdev->dev, "hclk");
> + if (IS_ERR(bp->hclk)) {
> + dev_err(&pdev->dev, "failed to get hclk\n");
> + goto err_out_put_pclk;
> + }
> +
> + clk_enable(bp->pclk);
> + clk_enable(bp->hclk);
> + }
This is the same kind of sillyness that started getting OMAP into problems
with the clk API. Just do this instead:
bp->pclk = clk_get(&pdev->dev, "pclk");
if (IS_ERR(bp->pclk)) {
dev_err(&pdev->dev, "failed to get pclk\n");
goto err_out_free_dev;
}
bp->hclk = clk_get(&pdev->dev, "hclk");
if (IS_ERR(bp->hclk)) {
dev_err(&pdev->dev, "failed to get hclk\n");
goto err_out_put_pclk;
}
clk_enable(bp->pclk);
clk_enable(bp->hclk);
And then require _all_ platforms using this driver to provide a pclk and
a hclk for this device, whether they exist in the SoC or not. Where they
don't, provide dummy clocks for it.
This probably means you end up with _less_ bloat overall because you're
not having to build the above code. You've less lines of source code to
maintain. You have a simplified dirver with consistent requirements
across all platforms. You don't need to read the version register, and
you don't need macb_is_at91() and macb_is_avr32().
With clkdev it's _cheap_ to provide these dummy clocks once you have one
dummy clock already in place.
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