drivers/pmdomain/actions/owl-sps-helper.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Actions Semi Owl Smart Power System (SPS) shared helpers
   4  *
   5  * Copyright 2012 Actions Semi Inc.
   6  * Author: Actions Semi, Inc.
   7  *
   8  * Copyright (c) 2017 Andreas Färber
   9  */
  10
  11 #include <linux/delay.h>
  12 #include <linux/io.h>
  13 #include <linux/soc/actions/owl-sps.h>
  14
  15 #define OWL_SPS_PG_CTL  0x0
  16
  17 int owl_sps_set_pg(void __iomem *base, u32 pwr_mask, u32 ack_mask, bool enable)
  18 {
  19         u32 val;
  20         bool ack;
  21         int timeout;
  22
  23         val = readl(base + OWL_SPS_PG_CTL);
  24         ack = val & ack_mask;
  25         if (ack == enable)
  26                 return 0;
  27
  28         if (enable)
  29                 val |= pwr_mask;
  30         else
  31                 val &= ~pwr_mask;
  32
  33         writel(val, base + OWL_SPS_PG_CTL);
  34
  35         for (timeout = 5000; timeout > 0; timeout -= 50) {
  36                 val = readl(base + OWL_SPS_PG_CTL);
  37                 if ((val & ack_mask) == (enable ? ack_mask : 0))
  38                         break;
  39                 udelay(50);
  40         }
  41         if (timeout <= 0)
  42                 return -ETIMEDOUT;
  43
  44         udelay(10);
  45
  46         return 0;
  47 }
  48 EXPORT_SYMBOL_GPL(owl_sps_set_pg);