Nishanth Menon <nm@xxxxxx> writes: > We now use Soc generic cpufreq-cpu0 driver using DT entries. > However to allow cpufreq-cpu0 and omap-cpufreq drivers to co-exist, > we need to ensure the following using the same image: > 1. With device tree boot, we use cpufreq-cpu0 > 2. With non device tree boot, we use omap-cpufreq > > In the case of (1), we will have cpu OPPs and regulator registered > as part of the DT, to ensure that omap-cpufreq and cpufreq-cpu0 don't > conflict in managing the frequency of the same cpu, we should not > permit init to pass in omap-cpufreq. > > In the case of (2), we will not have the cpufreq-cpu0 device, hence > only omap-cpufreq will be active. > > So, to acommodate both these usage conditions, we fail init of > omap-cpufreq when we boot with device tree. > > Cc: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> > Cc: Jon Hunter <jon-hunter@xxxxxx> > Cc: "Benoît Cousson" <b-cousson@xxxxxx> > Cc: Santosh Shilimkar <santosh.shilimkar@xxxxxx> > Cc: Shawn Guo <shawn.guo@xxxxxxxxxx> > Cc: Keerthy <j-keerthy@xxxxxx> > Cc: linux-omap@xxxxxxxxxxxxxxx > Cc: devicetree-discuss@xxxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > Cc: cpufreq@xxxxxxxxxxxxxxx > Cc: linux-pm@xxxxxxxxxxxxxxx > > Signed-off-by: Nishanth Menon <nm@xxxxxx> > --- > Changes in V2: > - donot remove support for omap-cpufreq in non-DT boot > - little more verbose commit log > V1: https://patchwork.kernel.org/patch/2273641/ > > drivers/cpufreq/omap-cpufreq.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c > index 9128c07..9382ed0 100644 > --- a/drivers/cpufreq/omap-cpufreq.c > +++ b/drivers/cpufreq/omap-cpufreq.c > @@ -22,6 +22,7 @@ > #include <linux/err.h> > #include <linux/clk.h> > #include <linux/io.h> > +#include <linux/of.h> > #include <linux/opp.h> > #include <linux/cpu.h> > #include <linux/module.h> > @@ -174,6 +175,19 @@ static inline void freq_table_free(void) > static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) > { > int result = 0; > + struct device_node *np; > + > + /* > + * If we have a device tree node describing OPPs, > + * we will NOT permit usage of omap-cpufreq driver. > + * use cpufreq-cpu0 driver to manage. > + */ > + if (of_have_populated_dt()) { > + for_each_child_of_node(of_find_node_by_path("/cpus"), np) { > + if (of_get_property(np, "operating-points", NULL)) > + return -EPERM; > + } > + } I think it's much cleaner to just convert this to a platform_driver like was done for the generic driver[1]. Then the registration in the previous patch can register the omap driver when needed. Kevin [1] https://patchwork.kernel.org/patch/2067751/ -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
