diff options
| -rw-r--r-- | arch/arm/mach-omap2/dvfs.c | 87 |
1 files changed, 86 insertions, 1 deletions
diff --git a/arch/arm/mach-omap2/dvfs.c b/arch/arm/mach-omap2/dvfs.c index 8832e4a4bdd..cefc2be3681 100644 --- a/arch/arm/mach-omap2/dvfs.c +++ b/arch/arm/mach-omap2/dvfs.c @@ -21,7 +21,7 @@ #include <plat/omap_device.h> /** - * struct omap_dev_user_list - Structure maitain userlist per devide + * struct omap_dev_user_list - Structure maitain userlist per device * * @dev: The device requesting for a particular frequency * @node: The list head entry @@ -413,6 +413,91 @@ static int omap_dvfs_remove_freq_request(struct omap_vdd_dvfs_info *dvfs_info, } /** + * omap_dvfs_voltage_scale() : API to scale the devices associated with a + * voltage domain vdd voltage. + * + * @dvfs_info: omap_vdd_dvfs_info pointer for the required vdd + * + * This API runs through the list of devices associated with the + * voltage domain and scales the device rates to the one requested + * by the user or those corresponding to the new voltage of the + * voltage domain. Target voltage is the highest voltage in the vdd_user_list. + * + * Returns 0 on success + * else the error value. + */ +static int omap_dvfs_voltage_scale(struct omap_vdd_dvfs_info *dvfs_info) +{ + unsigned long curr_volt; + int is_volt_scaled = 0; + struct omap_vdd_dev_list *temp_dev; + struct plist_node *node; + int ret = 0; + struct voltagedomain *voltdm; + unsigned long volt; + + if (!dvfs_info || IS_ERR(dvfs_info)) { + pr_warning("%s: VDD specified does not exist!\n", __func__); + return -EINVAL; + } + + voltdm = dvfs_info->voltdm; + + mutex_lock(&dvfs_info->scaling_mutex); + + /* Find the highest voltage being requested */ + node = plist_last(&dvfs_info->user_list); + volt = node->prio; + + curr_volt = omap_voltage_get_nom_volt(voltdm); + + if (curr_volt == volt) { + is_volt_scaled = 1; + } else if (curr_volt < volt) { + ret = omap_voltage_scale_vdd(voltdm, volt); + if (ret) { + pr_warning("%s: Unable to scale the %s to %ld volt\n", + __func__, voltdm->name, volt); + mutex_unlock(&dvfs_info->scaling_mutex); + return ret; + } + is_volt_scaled = 1; + } + + list_for_each_entry(temp_dev, &dvfs_info->dev_list, node) { + struct device *dev; + struct opp *opp; + unsigned long freq; + + dev = temp_dev->dev; + if (!plist_head_empty(&temp_dev->user_list)) { + node = plist_last(&temp_dev->user_list); + freq = node->prio; + } else { + opp = omap_dvfs_find_voltage(dev, volt); + if (IS_ERR(opp)) + continue; + freq = opp_get_freq(opp); + } + + if (freq == omap_device_get_rate(dev)) { + dev_dbg(dev, "%s: Already at the requested" + "rate %ld\n", __func__, freq); + continue; + } + + ret |= omap_device_set_rate(dev, freq); + } + + if (!is_volt_scaled && !ret) + omap_voltage_scale_vdd(voltdm, volt); + + mutex_unlock(&dvfs_info->scaling_mutex); + + return 0; +} + +/** * omap_dvfs_init() - Initialize omap dvfs layer * * Initalizes omap dvfs layer. It basically allocates memory for |