Mike Turquette <mturquette@xxxxxx> writes: > Introduce notifier infrastructure for VDD voltage transitions. Users can > register a notifier prior to a VDD's volt_scale function getting called > (VOLTSCALE_PRECHANGE) or after the VDD has been scaled > (VOLTSCALE_POSTCHANGE). > > Signed-off-by: Mike Turquette <mturquette@xxxxxx> > --- > All patches in this series based on PM branch (b6fb54b) plus Vishwa's 13 > OMAP3 DVFS patches (http://marc.info/?l=linux-omap&m=129561825804975&w=2). > Only validated on Zoom3 since OMAP4 DVFS patches were not available. > > arch/arm/mach-omap2/voltage.c | 47 ++++++++++++++++++++++++++++- > arch/arm/plat-omap/include/plat/voltage.h | 30 ++++++++++++++++++ > 2 files changed, 76 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/mach-omap2/voltage.c b/arch/arm/mach-omap2/voltage.c > index a0bd73b..0cbc58a 100644 > --- a/arch/arm/mach-omap2/voltage.c > +++ b/arch/arm/mach-omap2/voltage.c > @@ -729,6 +729,9 @@ static int __init omap3_vdd_data_configure(struct omap_vdd_info *vdd) > return -EINVAL; > } > > + /* initialize the voltage change notifier chain */ > + srcu_init_notifier_head(&vdd->volt_change_notify_chain); > + An explanation for the choice of SRCU notifiers would be useful. Kevin > if (!strcmp(vdd->voltdm.name, "mpu")) { > if (cpu_is_omap3630()) { > vdd->volt_data = omap36xx_vddmpu_volt_data; > @@ -912,6 +915,9 @@ static int __init omap4_vdd_data_configure(struct omap_vdd_info *vdd) > return -EINVAL; > } > > + /* initialize the voltage change notifier chain */ > + srcu_init_notifier_head(&vdd->volt_change_notify_chain); > + > if (!strcmp(vdd->voltdm.name, "mpu")) { > vdd->volt_data = omap44xx_vdd_mpu_volt_data; > vdd->vp_reg.tranxdone_status = > @@ -1201,7 +1207,9 @@ void omap_vp_disable(struct voltagedomain *voltdm) > int omap_voltage_scale_vdd(struct voltagedomain *voltdm, > unsigned long target_volt) > { > + int ret; > struct omap_vdd_info *vdd; > + struct omap_volt_change_info v_info; > > if (!voltdm || IS_ERR(voltdm)) { > pr_warning("%s: VDD specified does not exist!\n", __func__); > @@ -1216,7 +1224,20 @@ int omap_voltage_scale_vdd(struct voltagedomain *voltdm, > return -ENODATA; > } > > - return vdd->volt_scale(vdd, target_volt); > + /* load notifier chain data */ > + v_info.target_volt = target_volt; > + v_info.vdd = vdd; > + > + srcu_notifier_call_chain(&vdd->volt_change_notify_chain, > + VOLTSCALE_PRECHANGE, (void *)&v_info); > + > + ret = vdd->volt_scale(vdd, target_volt); > + > + if (!ret) > + srcu_notifier_call_chain(&vdd->volt_change_notify_chain, > + VOLTSCALE_POSTCHANGE, (void *)&v_info); > + > + return ret; > } > > /** > @@ -1437,6 +1458,30 @@ struct voltagedomain *omap_voltage_domain_lookup(char *name) > return ERR_PTR(-EINVAL); > } > > +int omap_voltage_register_notifier(struct omap_vdd_info *vdd, > + struct notifier_block *nb) > +{ > + if (!vdd || IS_ERR(vdd)) { > + pr_warning("%s: invalid VDD specified\n", __func__); > + return -EINVAL; > + } > + > + return srcu_notifier_chain_register(&vdd->volt_change_notify_chain, > + nb); > +} > + > +int omap_voltage_unregister_notifier(struct omap_vdd_info *vdd, > + struct notifier_block *nb) > +{ > + if (!vdd || IS_ERR(vdd)) { > + pr_warning("%s: invalid VDD specified\n", __func__); > + return -EINVAL; > + } > + > + return srcu_notifier_chain_unregister(&vdd->volt_change_notify_chain, > + nb); > +} > + > /** > * omap_voltage_late_init() - Init the various voltage parameters > * > diff --git a/arch/arm/plat-omap/include/plat/voltage.h b/arch/arm/plat-omap/include/plat/voltage.h > index e0b7f22..017e65b 100644 > --- a/arch/arm/plat-omap/include/plat/voltage.h > +++ b/arch/arm/plat-omap/include/plat/voltage.h > @@ -15,10 +15,14 @@ > #define __ARCH_ARM_MACH_OMAP2_VOLTAGE_H > > #include <linux/err.h> > +#include <linux/notifier.h> > > #define VOLTSCALE_VPFORCEUPDATE 1 > #define VOLTSCALE_VCBYPASS 2 > > +#define VOLTSCALE_PRECHANGE 0 > +#define VOLTSCALE_POSTCHANGE 1 > + > /* > * OMAP3 GENERIC setup times. Revisit to see if these needs to be > * passed from board or PMIC file > @@ -249,6 +253,7 @@ struct omap_vdd_info { > struct vc_reg_info vc_reg; > struct voltagedomain voltdm; > struct omap_vdd_dep_info *dep_vdd_info; > + struct srcu_notifier_head volt_change_notify_chain; > int nr_dep_vdd; > struct dentry *debug_dir; > u32 curr_volt; > @@ -261,6 +266,17 @@ struct omap_vdd_info { > unsigned long target_volt); > }; > > +/** > + * omap_volt_change_info - container used by voltage notifier chain > + * > + * @vdd_info : the voltage domain affected by the transition > + * @target_volt : voltage the affected domain is transitioning to > + */ > +struct omap_volt_change_info { > + unsigned long target_volt; > + struct omap_vdd_info *vdd; > +}; > + > unsigned long omap_vp_get_curr_volt(struct voltagedomain *voltdm); > void omap_vp_enable(struct voltagedomain *voltdm); > void omap_vp_disable(struct voltagedomain *voltdm); > @@ -280,6 +296,10 @@ void omap_change_voltscale_method(struct voltagedomain *voltdm, > int voltscale_method); > /* API to get the voltagedomain pointer */ > struct voltagedomain *omap_voltage_domain_lookup(char *name); > +int omap_voltage_register_notifier(struct omap_vdd_info *vdd, > + struct notifier_block *nb); > +int omap_voltage_unregister_notifier(struct omap_vdd_info *vdd, > + struct notifier_block *nb); > > int omap_voltage_late_init(void); > #else > @@ -298,6 +318,16 @@ static inline struct voltagedomain *omap_voltage_domain_lookup(char *name) > { > return ERR_PTR(-EINVAL); > } > +static inline int omap_voltage_register_notifier(struct omap_vdd_info *vdd, > + struct notifier block *nb) > +{ > + return 0; > +} > +static inline int omap_voltage_unregister_notifier(struct omap_vdd_info *vdd, > + struct notifier block *nb) > +{ > + return 0; > +} > #endif > > #endif -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
