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 
14 #define OWL_SPS_PG_CTL	0x0
15 
owl_sps_set_pg(void __iomem * base,u32 pwr_mask,u32 ack_mask,bool enable)16 int owl_sps_set_pg(void __iomem *base, u32 pwr_mask, u32 ack_mask, bool enable)
17 {
18 	u32 val;
19 	bool ack;
20 	int timeout;
21 
22 	val = readl(base + OWL_SPS_PG_CTL);
23 	ack = val & ack_mask;
24 	if (ack == enable)
25 		return 0;
26 
27 	if (enable)
28 		val |= pwr_mask;
29 	else
30 		val &= ~pwr_mask;
31 
32 	writel(val, base + OWL_SPS_PG_CTL);
33 
34 	for (timeout = 5000; timeout > 0; timeout -= 50) {
35 		val = readl(base + OWL_SPS_PG_CTL);
36 		if ((val & ack_mask) == (enable ? ack_mask : 0))
37 			break;
38 		udelay(50);
39 	}
40 	if (timeout <= 0)
41 		return -ETIMEDOUT;
42 
43 	udelay(10);
44 
45 	return 0;
46 }
47 EXPORT_SYMBOL_GPL(owl_sps_set_pg);
48