On Fri, 22 Aug 2014, Pankaj Dubey wrote: > From: Tomasz Figa <t.f...@samsung.com> > > Currently a syscon entity can be only registered directly through a > platform device that binds to a dedicated driver. However in certain use > cases it is desirable to make a device used with another driver a syscon > interface provider. For example, certain SoCs (e.g. Exynos) contain > system controller blocks which perform various functions such as power > domain control, CPU power management, low power mode control, but in > addition contain certain IP integration glue, such as various signal > masks, coprocessor power control, etc. In such case, there is a need to > have a dedicated driver for such system controller but also share > registers with other drivers. The latter is where the syscon interface > is helpful. > > This patch decouples syscon object from syscon driver, so that it can be > registered from any driver in addition to the original "syscon" platform > driver. > > Signed-off-by: Tomasz Figa <t.f...@samsung.com> > Signed-off-by: Pankaj Dubey <pankaj.du...@samsung.com> > --- > > RFC patch [1] was posted by Tomasz Figa. This patch addresses some of > comments given by Arnd to RFC patch, and further decouples syscon from > device model. It also gives flexibility of registering with syscon at > early stage using device_node object.
It would be helpful if Arnd gave this revision his blessing (Ack). > [1]: https://lkml.org/lkml/2014/6/17/331 > > drivers/mfd/syscon.c | 112 > ++++++++++++++++++++++++++++---------------- > include/linux/mfd/syscon.h | 14 ++++++ > 2 files changed, 86 insertions(+), 40 deletions(-) > > diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c > index ca15878..a91db30 100644 > --- a/drivers/mfd/syscon.c > +++ b/drivers/mfd/syscon.c > @@ -14,6 +14,7 @@ [...] > struct regmap *syscon_regmap_lookup_by_pdevname(const char *s) > { > - struct device *dev; > - struct syscon *syscon; > - > - dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s, > - syscon_match_pdevname); > - if (!dev) > - return ERR_PTR(-EPROBE_DEFER); > - > - syscon = dev_get_drvdata(dev); > + struct syscon *entry, *syscon = NULL; > + struct platform_device *pdev = NULL; > + > + spin_lock(&syscon_list_slock); > + list_for_each_entry(entry, &syscon_list, list) { > + pdev = of_find_device_by_node(entry->np); White space error. Did you run this through checkpatch.pl? > + if (pdev && !strcmp(dev_name(&pdev->dev), s)) { > + syscon = entry; > + break; > + } > + } > + spin_unlock(&syscon_list_slock); > > - return syscon->regmap; > + return syscon ? syscon->regmap : ERR_PTR(-EPROBE_DEFER); > } > EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_pdevname); [...] -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
