1 /*
2  * Actions Semi Owl Smart Power System (SPS) shared helpers
3  *
4  * Copyright 2012 Actions Semi Inc.
5  * Author: Actions Semi, Inc.
6  *
7  * Copyright (c) 2017 Andreas Färber
8  *
9  * This program is free software; you can redistribute  it and/or modify it
10  * under  the terms of  the GNU General  Public License as published by the
11  * Free Software Foundation;  either version 2 of the  License, or (at your
12  * option) any later version.
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/io.h>
17 
18 #define OWL_SPS_PG_CTL	0x0
19 
owl_sps_set_pg(void __iomem * base,u32 pwr_mask,u32 ack_mask,bool enable)20 int owl_sps_set_pg(void __iomem *base, u32 pwr_mask, u32 ack_mask, bool enable)
21 {
22 	u32 val;
23 	bool ack;
24 	int timeout;
25 
26 	val = readl(base + OWL_SPS_PG_CTL);
27 	ack = val & ack_mask;
28 	if (ack == enable)
29 		return 0;
30 
31 	if (enable)
32 		val |= pwr_mask;
33 	else
34 		val &= ~pwr_mask;
35 
36 	writel(val, base + OWL_SPS_PG_CTL);
37 
38 	for (timeout = 5000; timeout > 0; timeout -= 50) {
39 		val = readl(base + OWL_SPS_PG_CTL);
40 		if ((val & ack_mask) == (enable ? ack_mask : 0))
41 			break;
42 		udelay(50);
43 	}
44 	if (timeout <= 0)
45 		return -ETIMEDOUT;
46 
47 	udelay(10);
48 
49 	return 0;
50 }
51 EXPORT_SYMBOL_GPL(owl_sps_set_pg);
52