kernel/arch/arm/mach-ux500/pm_domains.c

   1 /*
   2  * Copyright (C) 2014 Linaro Ltd.
   3  *
   4  * Author: Ulf Hansson <ulf.hansson@linaro.org>
   5  * License terms: GNU General Public License (GPL) version 2
   6  *
   7  * Implements PM domains using the generic PM domain for ux500.
   8  */
   9 #include <linux/printk.h>
  10 #include <linux/slab.h>
  11 #include <linux/err.h>
  12 #include <linux/of.h>
  13 #include <linux/pm_domain.h>
  14
  15 #include <dt-bindings/arm/ux500_pm_domains.h>
  16 #include "pm_domains.h"
  17
  18 static int pd_power_off(struct generic_pm_domain *domain)
  19 {
  20         /*
  21          * Handle the gating of the PM domain regulator here.
  22          *
  23          * Drivers/subsystems handling devices in the PM domain needs to perform
  24          * register context save/restore from their respective runtime PM
  25          * callbacks, to be able to enable PM domain gating/ungating.
  26          */
  27         return 0;
  28 }
  29
  30 static int pd_power_on(struct generic_pm_domain *domain)
  31 {
  32         /*
  33          * Handle the ungating of the PM domain regulator here.
  34          *
  35          * Drivers/subsystems handling devices in the PM domain needs to perform
  36          * register context save/restore from their respective runtime PM
  37          * callbacks, to be able to enable PM domain gating/ungating.
  38          */
  39         return 0;
  40 }
  41
  42 static struct generic_pm_domain ux500_pm_domain_vape = {
  43         .name = "VAPE",
  44         .power_off = pd_power_off,
  45         .power_on = pd_power_on,
  46 };
  47
  48 static struct generic_pm_domain *ux500_pm_domains[NR_DOMAINS] = {
  49         [DOMAIN_VAPE] = &ux500_pm_domain_vape,
  50 };
  51
  52 static const struct of_device_id ux500_pm_domain_matches[] __initconst = {
  53         { .compatible = "stericsson,ux500-pm-domains", },
  54         { },
  55 };
  56
  57 int __init ux500_pm_domains_init(void)
  58 {
  59         struct device_node *np;
  60         struct genpd_onecell_data *genpd_data;
  61         int i;
  62
  63         np = of_find_matching_node(NULL, ux500_pm_domain_matches);
  64         if (!np)
  65                 return -ENODEV;
  66
  67         genpd_data = kzalloc(sizeof(*genpd_data), GFP_KERNEL);
  68         if (!genpd_data)
  69                 return -ENOMEM;
  70
  71         genpd_data->domains = ux500_pm_domains;
  72         genpd_data->num_domains = ARRAY_SIZE(ux500_pm_domains);
  73
  74         for (i = 0; i < ARRAY_SIZE(ux500_pm_domains); ++i)
  75                 pm_genpd_init(ux500_pm_domains[i], NULL, false);
  76
  77         of_genpd_add_provider_onecell(np, genpd_data);
  78         return 0;
  79 }