@@ -24,6 +24,9 @@
#include <linux/err.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/plist.h>
+#include <linux/slab.h>
#include <plat/common.h>
#include <plat/voltage.h>
@@ -85,6 +88,20 @@ struct vp_reg_val {
};
/**
+ * struct omap_vdd_user_list - The per vdd user list
+ *
+ * @dev: The device asking for the vdd to be set at a particular
+ * voltage
+ * @node: The list head entry
+ * @volt: The voltage requested by the device <dev>
+ */
+struct omap_vdd_user_list {
+ struct device *dev;
+ struct plist_node node;
+ u32 volt;
+};
+
+/**
* omap_vdd_info - Per Voltage Domain info
*
* @volt_data : voltage table having the distinct voltages supported
@@ -95,9 +112,13 @@ struct vp_reg_val {
* vp registers
* @voltdm : pointer to the voltage domain structure
* @debug_dir : debug directory for this voltage domain.
+ * @user_lock : the lock to be used by the plist user_list
+ * @user_list : the list head maintaining the various users.
+ * @scaling_mutex : the dvfs muutex.
+ * of this vdd with the voltage requested by each user.
* @volt_data_count : number of distinct voltages supported by this vdd.
* @nominal_volt : nominal voltage for this vdd.
- * @curr_volt : current voltage for this vdd;
+ * @curr_volt : current voltage for this vdd.
* cmdval_reg : voltage controller cmdval register.
* @vdd_sr_reg : the smartreflex register associated with this VDD.
*/
@@ -107,6 +128,9 @@ struct omap_vdd_info{
struct vp_reg_val vp_reg;
struct voltagedomain voltdm;
struct dentry *debug_dir;
+ spinlock_t user_lock;
+ struct plist_head user_list;
+ struct mutex scaling_mutex;
int volt_data_count;
u32 nominal_volt;
u32 curr_volt;
@@ -591,6 +615,12 @@ static void __init omap3_vdd_data_configure(struct omap_vdd_info *vdd)
vdd->vp_reg.vlimitto_vddmin_shift = OMAP3430_VDDMIN_SHIFT;
vdd->vp_reg.vlimitto_vddmax_shift = OMAP3430_VDDMAX_SHIFT;
vdd->vp_reg.vlimitto_timeout_shift = OMAP3430_TIMEOUT_SHIFT;
+
+ /* Init the plist */
+ spin_lock_init(&vdd->user_lock);
+ plist_head_init(&vdd->user_list, &vdd->user_lock);
+ /* Init the DVFS mutex */
+ mutex_init(&vdd->scaling_mutex);
}
/* OMAP4 specific voltage init functions */
@@ -715,6 +745,12 @@ static void __init omap4_vdd_data_configure(struct omap_vdd_info *vdd)
vdd->vp_reg.vlimitto_vddmin_shift = OMAP4430_VDDMIN_SHIFT;
vdd->vp_reg.vlimitto_vddmax_shift = OMAP4430_VDDMAX_SHIFT;
vdd->vp_reg.vlimitto_timeout_shift = OMAP4430_TIMEOUT_SHIFT;
+
+ /* Init the plist */
+ spin_lock_init(&vdd->user_lock);
+ plist_head_init(&vdd->user_list, &vdd->user_lock);
+ /* Init the DVFS mutex */
+ mutex_init(&vdd->scaling_mutex);
}
/* Generic voltage init functions */
@@ -1140,6 +1176,69 @@ unsigned long omap_vp_get_curr_volt(struct voltagedomain *voltdm)
return volt_pmic_info.vsel_to_uv(curr_vsel);
}
+/**
+ * omap_voltage_add_request() - API to keep track of various requests to
+ * scale the VDD and returns the best possible
+ * voltage the VDD can be put to.
+ * @volt_domain: pointer to the voltage domain.
+ * @dev: the device pointer.
+ * @volt: the voltage which is requested by the device.
+ *
+ * This API is to be called before the actual voltage scaling is
+ * done to determine what is the best possible voltage the VDD can
+ * be put to. This API adds the device <dev> in the user list of the
+ * vdd <volt_domain> with <volt> as the requested voltage. The user list
+ * is a plist with the priority element absolute voltage values.
+ * The API then finds the maximum of all the requested voltages for
+ * the VDD and returns it back through <volt> pointer itself.
+ * Returns error value in case of any errors.
+ */
+int omap_voltage_add_request(struct voltagedomain *voltdm, struct device *dev,
+ unsigned long *volt)
+{
+ struct omap_vdd_info *vdd;
+ struct omap_vdd_user_list *user;
+ struct plist_node *node;
+ int found = 0;
+
+ if (!voltdm || IS_ERR(voltdm)) {
+ pr_warning("%s: VDD specified does not exist!\n", __func__);
+ return -EINVAL;
+ }
+
+ vdd = container_of(voltdm, struct omap_vdd_info, voltdm);
+
+ mutex_lock(&vdd->scaling_mutex);
+
+ plist_for_each_entry(user, &vdd->user_list, node) {
+ if (user->dev == dev) {
+ found = 1;
+ break;
+ }
+ }
+
+ if (!found) {
+ user = kzalloc(sizeof(struct omap_vdd_user_list), GFP_KERNEL);
+ if (!user) {
+ pr_err("%s: Unable to creat a new user for vdd_%s\n",
+ __func__, voltdm->name);
+ mutex_unlock(&vdd->scaling_mutex);
+ return -ENOMEM;
+ }
+ user->dev = dev;
+ } else {
+ plist_del(&user->node, &vdd->user_list);
+ }
+
+ plist_node_init(&user->node, *volt);
+ plist_add(&user->node, &vdd->user_list);
+ node = plist_last(&vdd->user_list);
+ *volt = user->volt = node->prio;
+
+ mutex_unlock(&vdd->scaling_mutex);
+
+ return 0;
+}
/**
* omap_vp_enable() - API to enable a particular VP
@@ -150,11 +150,18 @@ bool omap_voltage_override_params(struct voltagedomain *voltdm);
void omap_voltage_register_pmic(struct omap_volt_pmic_info *pmic_info);
void omap_voltage_init_vc(struct omap_volt_vc_data *setup_vc);
void omap_change_voltscale_method(int voltscale_method);
+int omap_voltage_add_request(struct voltagedomain *voltdm, struct device *dev,
+ unsigned long *volt);
#else
static inline void omap_voltage_register_pmic
(struct omap_volt_pmic_info *pmic_info) {}
static inline void omap_voltage_init_vc(struct omap_volt_vc_data *setup_vc) {}
static inline void omap_change_voltscale_method(int voltscale_method) {}
+static inline int omap_voltage_add_request(struct voltagedomain *voltdm,
+ struct device *dev, unsigned long *volt)
+{
+ return -EINVAL;
+}
#endif
#endif