From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Holt Subject: Re: [RFC 2/4] [flexcan] Introduce a flexcan_clk set of functions. Date: Fri, 5 Aug 2011 06:36:38 -0500 Message-ID: <20110805113638.GF4926@sgi.com> References: <1312509979-13226-1-git-send-email-holt@sgi.com> <1312509979-13226-3-git-send-email-holt@sgi.com> <4E3BAB03.4040803@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Robin Holt , Wolfgang Grandegger , socketcan-core@lists.berlios.de, netdev@vger.kernel.org To: Marc Kleine-Budde Return-path: Received: from relay3.sgi.com ([192.48.152.1]:36332 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750710Ab1HELgk (ORCPT ); Fri, 5 Aug 2011 07:36:40 -0400 Content-Disposition: inline In-Reply-To: <4E3BAB03.4040803@pengutronix.de> Sender: netdev-owner@vger.kernel.org List-ID: I implemented the coding style changes below (Sorry I missed the two the first time). As for a better implementation, I guess I would need to understand what is being attempted here. I only marginally understand the flexcan hardware on the Freescale P1010 and certainly am clueless about arm implementations of flexcan. I just skimmed over freescale's site and it looks like I would be looking at their i.MX25, i.MX28, i.MX35, and i.MX53 family of processors. I will attempt to find some useful documentation of those and look at the kernel sources for what the clk_* functions are trying to accomplish. I _THINK_ I understand. It looks like I could implement this as a powerpc p1010 specific thing and get the same effect without impacting flexcan.c. I also think I understand that the i.MX25 family of processors do essentially the same thing the p1010 is doing for determining the clock rate. Thanks, Robin On Fri, Aug 05, 2011 at 10:34:11AM +0200, Marc Kleine-Budde wrote: > On 08/05/2011 04:06 AM, Robin Holt wrote: > > The freescale P1010RDB board does not have a > > clk_{get,put,get_rate,enable,disable} set of functions. Wrap these with a > > flexcan_ #define for arm, and implement a more complete function for ppc. > > Some codingstyle nitpicks inline. I hope we'll find a cleaner solution > than this patch. > > Marc > > > Signed-off-by: Robin Holt > > To: Marc Kleine-Budde > > To: Wolfgang Grandegger > > Cc: socketcan-core@lists.berlios.de > > Cc: netdev@vger.kernel.org > > --- > > drivers/net/can/flexcan.c | 114 +++++++++++++++++++++++++++++++++++++++++---- > > 1 files changed, 105 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > > index 74b1706..3417d0b 100644 > > --- a/drivers/net/can/flexcan.c > > +++ b/drivers/net/can/flexcan.c > > @@ -220,6 +220,102 @@ static inline void flexcan_write(u32 val, void __iomem *addr) > > } > > #endif > > > > +#if defined(__powerpc__) > > +struct flexcan_clk { > > + unsigned long rate; > > + void *data; > > +}; > > + > > +static struct clk *flexcan_clk_get(struct device *dev, const char *id) > > +{ > > + struct flexcan_clk *clock; > > + u32 *clock_freq; > > + u32 *clock_divider; > > + int err; > > + > > + clock = kmalloc(sizeof(struct flexcan_clk), GFP_KERNEL); > > + if (!clock) { > > + dev_err(dev, "Cannot allocate memory\n"); > > + err = -ENOMEM; > > + goto failed_clock; > > + } > > + clock_freq = (u32 *)of_get_property(dev->of_node, "clock_freq", NULL); > > + if (!clock_freq) { > > + dev_err(dev, "Cannot find clock_freq property\n"); > > + err = -EINVAL; > > + goto failed_clock; > > + } > > + > > + clock_divider = (u32 *) of_get_property(dev->of_node, > ^ > > remove this space, please > > + "fsl,flexcan-clock-divider", NULL); > > + if (clock_divider == NULL) { > > !clock_divider > > > + dev_err(dev, "Cannot find fsl,flexcan-clock-divider property\n"); > > + err = -EINVAL; > > + goto failed_clock; > > + } > > + > > + clock->rate = DIV_ROUND_CLOSEST(*clock_freq / *clock_divider, 1000); > > + clock->rate *= 1000; > > + > > + return (struct clk *)clock; > > + > > + failed_clock: > > + kfree(clock); > > + return ERR_PTR(err); > > +} > > + > > +static inline void flexcan_clk_put(struct clk *_clk) > > +{ > > + struct flexcan_clk *clk = (struct flexcan_clk *)_clk; > > that cast is not needed. > > > + > > + kfree(clk); > > +} > > + > > +static inline int flexcan_clk_enable(struct clk *clk) > > +{ > > + return 0; > > +} > > + > > +static inline void flexcan_clk_disable(struct clk *clk) > > +{ > > + return; > > +} > > + > > +static inline unsigned long flexcan_clk_get_rate(struct clk *_clk) > > +{ > > + struct flexcan_clk *clk = (struct flexcan_clk *)_clk; > > + > > + return clk->rate; > > +} > > + > > +#else > > +static inline struct clk *flexcan_clk_get(struct device *dev, const char *id) > > +{ > > + return clk_get(dev, id); > > +} > > + > > +static inline void flexcan_clk_put(struct clk *clk) > > +{ > > + clk_put(clk); > > +} > > + > > +static inline int flexcan_clk_enable(struct clk *clk) > > +{ > > + return clk_enable(clk); > > +} > > + > > +static inline void flexcan_clk_disable(struct clk *clk) > > +{ > > + clk_disable(clk); > > +} > > + > > +static inline unsigned long flexcan_clk_get_rate(struct clk *clk) > > +{ > > + return clk_get_rate(clk); > > +} > > + > > +#endif > > + > > /* > > * Swtich transceiver on or off > > */ > > @@ -807,7 +903,7 @@ static int flexcan_open(struct net_device *dev) > > struct flexcan_priv *priv = netdev_priv(dev); > > int err; > > > > - clk_enable(priv->clk); > > + flexcan_clk_enable(priv->clk); > > > > err = open_candev(dev); > > if (err) > > @@ -829,7 +925,7 @@ static int flexcan_open(struct net_device *dev) > > out_close: > > close_candev(dev); > > out: > > - clk_disable(priv->clk); > > + flexcan_clk_disable(priv->clk); > > > > return err; > > } > > @@ -843,7 +939,7 @@ static int flexcan_close(struct net_device *dev) > > flexcan_chip_stop(dev); > > > > free_irq(dev->irq, dev); > > - clk_disable(priv->clk); > > + flexcan_clk_disable(priv->clk); > > > > close_candev(dev); > > > > @@ -882,7 +978,7 @@ static int __devinit register_flexcandev(struct net_device *dev) > > struct flexcan_regs __iomem *regs = priv->base; > > u32 reg, err; > > > > - clk_enable(priv->clk); > > + flexcan_clk_enable(priv->clk); > > > > /* select "bus clock", chip must be disabled */ > > flexcan_chip_disable(priv); > > @@ -916,7 +1012,7 @@ static int __devinit register_flexcandev(struct net_device *dev) > > out: > > /* disable core and turn off clocks */ > > flexcan_chip_disable(priv); > > - clk_disable(priv->clk); > > + flexcan_clk_disable(priv->clk); > > > > return err; > > } > > @@ -936,7 +1032,7 @@ static int __devinit flexcan_probe(struct platform_device *pdev) > > resource_size_t mem_size; > > int err, irq; > > > > - clk = clk_get(&pdev->dev, NULL); > > + clk = flexcan_clk_get(&pdev->dev, NULL); > > if (IS_ERR(clk)) { > > dev_err(&pdev->dev, "no clock defined\n"); > > err = PTR_ERR(clk); > > @@ -973,7 +1069,7 @@ 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 = flexcan_clk_get_rate(clk); > > 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; > > @@ -1008,7 +1104,7 @@ static int __devinit flexcan_probe(struct platform_device *pdev) > > failed_map: > > release_mem_region(mem->start, mem_size); > > failed_get: > > - clk_put(clk); > > + flexcan_clk_put(clk); > > failed_clock: > > return err; > > } > > @@ -1026,7 +1122,7 @@ 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); > > + flexcan_clk_put(priv->clk); > > > > free_candev(dev); > > > > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Industrial Linux Solutions | Phone: +49-231-2826-924 | > Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | > Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | >