On Fri, Mar 06, 2015 at 06:48:16PM +0800, yong.wu@xxxxxxxxxxxx wrote: > From: Yong Wu <yong.wu@xxxxxxxxxxxx> > > This patch add SMI(Smart Multimedia Interface) driver. This driver is > responsible to enable/disable iommu and control the clocks of each > local arbiter. > > Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> > --- > drivers/soc/mediatek/Kconfig | 7 ++ > drivers/soc/mediatek/Makefile | 1 + > drivers/soc/mediatek/mt8173-smi.c | 143 ++++++++++++++++++++++++++++++++++++++ > include/linux/mtk-smi.h | 40 +++++++++++ I just posted the power domain driver for prividing the domains this driver uses. You should base your code on that. > +#include <linux/mm.h> > + > +#define SMI_LARB_MMU_EN (0xf00) > +#define F_SMI_MMU_EN(port) (1 << (port)) > + > +struct mtk_smi_larb { > + void __iomem *larb_base; > + struct clk *larb_clk[3];/* each larb has 3 clk at most */ > +}; > + > +static const char * const mtk_smi_clk_name[] = { > + "larb_sub0", "larb_sub1", "larb_sub2" > +}; > + > +static const struct of_device_id mtk_smi_of_ids[] = { > + { .compatible = "mediatek,mt8173-smi-larb", > + }, Add a newline after the opening brace. > +int mtk_smi_config_port(struct platform_device *plarbdev, > + unsigned int larbportid) > +{ > + struct mtk_smi_larb *larbpriv = dev_get_drvdata(&plarbdev->dev); > + int ret; > + u32 reg; > + > + ret = mtk_smi_larb_get(plarbdev); > + if (ret) > + return ret; > + > + reg = readl(larbpriv->larb_base + SMI_LARB_MMU_EN); > + reg &= ~F_SMI_MMU_EN(larbportid); > + reg |= F_SMI_MMU_EN(larbportid); This sets the very same bits that are cleared one line above. This is surely not what you want. > + writel(reg, larbpriv->larb_base + SMI_LARB_MMU_EN); > + > + mtk_smi_larb_put(plarbdev); > + > + return 0; > +} > + > +static int mtk_smi_probe(struct platform_device *pdev) > +{ > + struct mtk_smi_larb *larbpriv; > + struct resource *res; > + struct device *dev = &pdev->dev; > + unsigned int i; > + > + larbpriv = devm_kzalloc(dev, sizeof(struct mtk_smi_larb), GFP_KERNEL); sizeof(*larbpriv) > + if (!larbpriv) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + larbpriv->larb_base = devm_ioremap_resource(dev, res); > + if (IS_ERR(larbpriv->larb_base)) { > + dev_err(dev, "larbbase %p err\n", larbpriv->larb_base); You can print an error number with %ld and PTR_ERR(larbpriv->larb_base). Printing the pointer is not that helpful. > +/* > + * Enable iommu for each port, it is only for iommu. > + * > + * Returns 0 if successfully, others if failed. > + */ > +int mtk_smi_config_port(struct platform_device *pdev, > + unsigned int larbportid); > + > +/* > + * The multimedia module should call the two function below > + * which help open/close the clock of the larb. > + * so the client dtsi should add the larb like "larb = <&larb0>" > + * to get platform_device. > + * > + * mtk_smi_larb_get should be called before the multimedia h/w work. > + * mtk_smi_larb_put should be called after h/w done. > + * > + * Returns 0 if successfully, others if failed. > + */ > +int mtk_smi_larb_get(struct platform_device *plarbdev); > +void mtk_smi_larb_put(struct platform_device *plarbdev); The function documentation usually comes with the definition of a function, not its declaration. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html