Re: [PATCH v8 05/22] mfd: omap-usb-tll: Clean up clock handling

[Russell King - ARM Linux <linux@arm.linux.org.uk>]

On Fri, Jan 18, 2013 at 02:17:08PM +0200, Roger Quadros wrote:
> +	tll->ch_clk = devm_kzalloc(dev, sizeof(struct clk * [tll->nch]),
> +						GFP_KERNEL);
> +	if (!tll->ch_clk) {
> +		ret = -ENOMEM;
> +		dev_err(dev, "Couldn't allocate memory for channel clocks\n");
> +		goto err_clk_alloc;
> +	}
> +
> +	for (i = 0; i < tll->nch; i++) {
> +		char clkname[] = "usb_tll_hs_usb_chx_clk";
> +		struct clk *fck;
> +
> +		snprintf(clkname, sizeof(clkname),
> +					"usb_tll_hs_usb_ch%d_clk", i);
> +		fck = clk_get(dev, clkname);
> +
> +		if (IS_ERR(fck))
> +			dev_dbg(dev, "can't get clock : %s\n", clkname);
> +		else
> +			tll->ch_clk[i] = fck;

Hmm.  I'd actually suggest that this becomes:

		tll->ch_clk[i] = fck;
		if (IS_ERR(fck)
			dev_dbg(dev, "can't get clock: %s\n", clkname);

so that tll->ch_clk is always written to.

>  static int usbtll_omap_remove(struct platform_device *pdev)
>  {
>  	struct usbtll_omap *tll = platform_get_drvdata(pdev);
> +	int i;
> +
> +	for (i = 0; i < tll->nch; i++)
> +		clk_put(tll->ch_clk[i]);

And change this to:

	for (i = 0; i < tll->nch; i++)
		if (!IS_ERR(tll->ch_clk[i]))
			clk_put(tll->ch_clk[i]);

so that you're not passing a NULL pointer in.

> +	for (i = 0; i < tll->nch; i++) {
> +		if (is_ehci_tll_mode(pdata->port_mode[i])) {
> +			int r;
>  
> -	if (is_ehci_tll_mode(pdata->port_mode[1]))
> -		clk_enable(tll->usbtll_p2_fck);
> +			if (!tll->ch_clk[i])

			if (IS_ERR(tll->ch_clk[i]))

> +				continue;
> +
> +			r = clk_enable(tll->ch_clk[i]);
> +			if (r) {
> +				dev_err(dev,
> +				 "Error enabling ch %d clock: %d\n", i, r);
> +			}
> +		}
> +	}

> @@ -387,11 +409,12 @@ static int usbtll_runtime_suspend(struct device *dev)
>  
>  	spin_lock_irqsave(&tll->lock, flags);
>  
> -	if (is_ehci_tll_mode(pdata->port_mode[0]))
> -		clk_disable(tll->usbtll_p1_fck);
> -
> -	if (is_ehci_tll_mode(pdata->port_mode[1]))
> -		clk_disable(tll->usbtll_p2_fck);
> +	for (i = 0; i < tll->nch; i++) {
> +		if (is_ehci_tll_mode(pdata->port_mode[i])) {
> +			if (tll->ch_clk[i])

			if (!IS_ERR(tll->ch_clk[i]))

> +				clk_disable(tll->ch_clk[i]);
> +		}
> +	}
>  
>  	spin_unlock_irqrestore(&tll->lock, flags);
>  
> -- 
> 1.7.4.1
>