From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Holt Subject: [PATCH v11 5/6] flexcan: Prefer device tree clock frequency if available. Date: Thu, 11 Aug 2011 11:07:10 -0500 Message-ID: <1313078831-2511-6-git-send-email-holt@sgi.com> References: <1313078831-2511-1-git-send-email-holt@sgi.com> Cc: Robin Holt , socketcan-core@lists.berlios.de, netdev@vger.kernel.org, PPC list , devicetree-discuss@lists.ozlabs.org To: Robin Holt , Kumar Gala , Wolfgang Grandegger , Marc Kleine-Budde , U Bhaskar-B22300 Received: from relay3.sgi.com ([192.48.152.1]:60191 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753186Ab1HKQHj (ORCPT ); Thu, 11 Aug 2011 12:07:39 -0400 In-Reply-To: <1313078831-2511-1-git-send-email-holt@sgi.com> Sender: netdev-owner@vger.kernel.org List-ID: If our CAN device's device tree node has a clock-frequency property, then use that value for the can devices clock frequency. If not, fall back to asking the platform/mach code for the clock frequency associated with the flexcan device. Signed-off-by: Robin Holt To: Kumar Gala To: Wolfgang Grandegger , To: Marc Kleine-Budde , To: U Bhaskar-B22300 To: Scott Wood To: Grant Likely Cc: socketcan-core@lists.berlios.de, Cc: netdev@vger.kernel.org, Cc: PPC list Cc: devicetree-discuss@lists.ozlabs.org --- .../devicetree/bindings/net/can/fsl-flexcan.txt | 2 + drivers/net/can/flexcan.c | 33 +++++++++++++++----- 2 files changed, 27 insertions(+), 8 deletions(-) diff --git a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt index c78dcbb..a4382c7 100644 --- a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt +++ b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt @@ -11,6 +11,7 @@ Required properties: - reg : Offset and length of the register set for this device - interrupts : Interrupt tuple for this device +- clock-frequency : The oscillator frequency driving the flexcan device Example: @@ -19,4 +20,5 @@ Example: reg = <0x1c000 0x1000>; interrupts = <48 0x2>; interrupt-parent = <&mpic>; + clock-frequency = <0x0bebc1fc>; }; diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 662f832..d40c38e 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #define DRV_NAME "flexcan" @@ -929,12 +930,26 @@ static int __devinit flexcan_probe(struct platform_device *pdev) void __iomem *base; resource_size_t mem_size; int err, irq; + u32 clock_freq = 0; - clk = clk_get(&pdev->dev, NULL); - if (IS_ERR(clk)) { - dev_err(&pdev->dev, "no clock defined\n"); - err = PTR_ERR(clk); - goto failed_clock; + if (pdev->dev.of_node) { + const u32 *clock_freq_p; + + clk = NULL; + clock_freq_p = of_get_property(pdev->dev.of_node, + "clock-frequency", NULL); + if (clock_freq_p) + clock_freq = *clock_freq_p; + } + + if (!clock_freq) { + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "no clock defined\n"); + err = PTR_ERR(clk); + goto failed_clock; + } + clock_freq = clk_get_rate(clk); } mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -967,7 +982,7 @@ static int __devinit flexcan_probe(struct platform_device *pdev) dev->flags |= IFF_ECHO; /* we support local echo in hardware */ priv = netdev_priv(dev); - priv->can.clock.freq = clk_get_rate(clk); + priv->can.clock.freq = clock_freq; priv->can.bittiming_const = &flexcan_bittiming_const; priv->can.do_set_mode = flexcan_set_mode; priv->can.do_get_berr_counter = flexcan_get_berr_counter; @@ -1002,7 +1017,8 @@ static int __devinit flexcan_probe(struct platform_device *pdev) failed_map: release_mem_region(mem->start, mem_size); failed_get: - clk_put(clk); + if (clk) + clk_put(clk); failed_clock: return err; } @@ -1020,7 +1036,8 @@ static int __devexit flexcan_remove(struct platform_device *pdev) mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); release_mem_region(mem->start, resource_size(mem)); - clk_put(priv->clk); + if (priv->clk) + clk_put(priv->clk); free_candev(dev); -- 1.7.2.1