LXR linux/drivers/soc/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
  17int 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}
  48EXPORT_SYMBOL_GPL(owl_sps_set_pg);
  49