Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932335Ab3GQPd5 (ORCPT ); Wed, 17 Jul 2013 11:33:57 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:42267 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756208Ab3GQPdz (ORCPT ); Wed, 17 Jul 2013 11:33:55 -0400 Date: Wed, 17 Jul 2013 11:33:54 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Boris BREZILLON cc: Nicolas Ferre , Ludovic Desroches , Jean-Christophe Plagniol-Villard , Greg Kroah-Hartman , , , Subject: Re: [PATCH v3 6/7] USB: ohci-at91: add usb_clk for transition to common clk framework In-Reply-To: <1373988136-24622-1-git-send-email-b.brezillon@overkiz.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1603 Lines: 42 On Tue, 16 Jul 2013, Boris BREZILLON wrote: > The AT91 PMC (Power Management Controller) provides an USB clock used by > USB Full Speed host (ohci) and USB Full Speed device (udc). > The usb drivers (ohci and udc) must configure this clock to 48Mhz. > This configuration was formely done in mach-at91/clock.c, but this > implementation will be removed when moving to common clk framework. > > This patch add support for usb clock retrieval and configuration, and is > backward compatible with the current at91 clk implementation (if usb clk > is not found, it does not configure/enable the usb clk). This does not take into account any of the changes you discussed with Russell King and me -- it is exactly the same as the previous version. > @@ -144,6 +150,11 @@ static int usb_hcd_at91_probe(const struct hc_driver *driver, > goto err2; > } > > + uclk = clk_get(&pdev->dev, "usb_clk"); > + if (IS_ERR(uclk)) { > + uclk = NULL; > + dev_warn(&pdev->dev, "failed to get usb_clk\n"); > + } > iclk = clk_get(&pdev->dev, "ohci_clk"); > if (IS_ERR(iclk)) { > dev_err(&pdev->dev, "failed to get ohci_clk\n"); > @@ -212,10 +223,11 @@ static void usb_hcd_at91_remove(struct usb_hcd *hcd, > release_mem_region(hcd->rsrc_start, hcd->rsrc_len); > usb_put_hcd(hcd); > > + clk_put(uclk); What will clk_put() do when uclk is NULL? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/