[deliverable/linux.git] / drivers / power / reset / at91-poweroff.c

/*
 * Atmel AT91 SAM9 SoCs reset code
 *
 * Copyright (C) 2007 Atmel Corporation.
 * Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
 * Copyright (C) 2014 Free Electrons
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/printk.h>

#define AT91_SHDW_CR	0x00		/* Shut Down Control Register */
#define AT91_SHDW_SHDW		BIT(0)			/* Shut Down command */
#define AT91_SHDW_KEY		(0xa5 << 24)		/* KEY Password */

#define AT91_SHDW_MR	0x04		/* Shut Down Mode Register */
#define AT91_SHDW_WKMODE0	GENMASK(2, 0)		/* Wake-up 0 Mode Selection */
#define AT91_SHDW_CPTWK0_MAX	0xf			/* Maximum Counter On Wake Up 0 */
#define AT91_SHDW_CPTWK0	(AT91_SHDW_CPTWK0_MAX << 4) /* Counter On Wake Up 0 */
#define AT91_SHDW_CPTWK0_(x)	((x) << 4)
#define AT91_SHDW_RTTWKEN	BIT(16)			/* Real Time Timer Wake-up Enable */
#define AT91_SHDW_RTCWKEN	BIT(17)			/* Real Time Clock Wake-up Enable */

#define AT91_SHDW_SR	0x08		/* Shut Down Status Register */
#define AT91_SHDW_WAKEUP0	BIT(0)			/* Wake-up 0 Status */
#define AT91_SHDW_RTTWK		BIT(16)			/* Real-time Timer Wake-up */
#define AT91_SHDW_RTCWK		BIT(17)			/* Real-time Clock Wake-up [SAM9RL] */

enum wakeup_type {
	AT91_SHDW_WKMODE0_NONE		= 0,
	AT91_SHDW_WKMODE0_HIGH		= 1,
	AT91_SHDW_WKMODE0_LOW		= 2,
	AT91_SHDW_WKMODE0_ANYLEVEL	= 3,
};

static const char *shdwc_wakeup_modes[] = {
	[AT91_SHDW_WKMODE0_NONE]	= "none",
	[AT91_SHDW_WKMODE0_HIGH]	= "high",
	[AT91_SHDW_WKMODE0_LOW]		= "low",
	[AT91_SHDW_WKMODE0_ANYLEVEL]	= "any",
};

static void __iomem *at91_shdwc_base;

static void __init at91_wakeup_status(void)
{
	u32 reg = readl(at91_shdwc_base + AT91_SHDW_SR);
	char *reason = "unknown";

	/* Simple power-on, just bail out */
	if (!reg)
		return;

	if (reg & AT91_SHDW_RTTWK)
		reason = "RTT";
	else if (reg & AT91_SHDW_RTCWK)
		reason = "RTC";

	pr_info("AT91: Wake-Up source: %s\n", reason);
}

static void at91_poweroff(void)
{
	writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, at91_shdwc_base + AT91_SHDW_CR);
}

static int at91_poweroff_get_wakeup_mode(struct device_node *np)
{
	const char *pm;
	unsigned int i;
	int err;

	err = of_property_read_string(np, "atmel,wakeup-mode", &pm);
	if (err < 0)
		return AT91_SHDW_WKMODE0_ANYLEVEL;

	for (i = 0; i < ARRAY_SIZE(shdwc_wakeup_modes); i++)
		if (!strcasecmp(pm, shdwc_wakeup_modes[i]))
			return i;

	return -ENODEV;
}

static void at91_poweroff_dt_set_wakeup_mode(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	int wakeup_mode;
	u32 mode = 0, tmp;

	wakeup_mode = at91_poweroff_get_wakeup_mode(np);
	if (wakeup_mode < 0) {
		dev_warn(&pdev->dev, "shdwc unknown wakeup mode\n");
		return;
	}

	if (!of_property_read_u32(np, "atmel,wakeup-counter", &tmp)) {
		if (tmp > AT91_SHDW_CPTWK0_MAX) {
			dev_warn(&pdev->dev,
				 "shdwc wakeup counter 0x%x > 0x%x reduce it to 0x%x\n",
				 tmp, AT91_SHDW_CPTWK0_MAX, AT91_SHDW_CPTWK0_MAX);
			tmp = AT91_SHDW_CPTWK0_MAX;
		}
		mode |= AT91_SHDW_CPTWK0_(tmp);
	}

	if (of_property_read_bool(np, "atmel,wakeup-rtc-timer"))
			mode |= AT91_SHDW_RTCWKEN;

	if (of_property_read_bool(np, "atmel,wakeup-rtt-timer"))
			mode |= AT91_SHDW_RTTWKEN;

	writel(wakeup_mode | mode, at91_shdwc_base + AT91_SHDW_MR);
}

static int at91_poweroff_probe(struct platform_device *pdev)
{
	struct resource *res;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(at91_shdwc_base)) {
		dev_err(&pdev->dev, "Could not map reset controller address\n");
		return PTR_ERR(at91_shdwc_base);
	}

	at91_wakeup_status();

	if (pdev->dev.of_node)
		at91_poweroff_dt_set_wakeup_mode(pdev);

	pm_power_off = at91_poweroff;

	return 0;
}

static const struct of_device_id at91_poweroff_of_match[] = {
	{ .compatible = "atmel,at91sam9260-shdwc", },
	{ .compatible = "atmel,at91sam9rl-shdwc", },
	{ .compatible = "atmel,at91sam9x5-shdwc", },
	{ /*sentinel*/ }
};

static struct platform_driver at91_poweroff_driver = {
	.probe = at91_poweroff_probe,
	.driver = {
		.name = "at91-poweroff",
		.of_match_table = at91_poweroff_of_match,
	},
};
module_platform_driver(at91_poweroff_driver);
Commit	Line	Data
ae499f0f MR	1	/*
	2	* Atmel AT91 SAM9 SoCs reset code
	3	*
	4	* Copyright (C) 2007 Atmel Corporation.
	5	* Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
	6	* Copyright (C) 2014 Free Electrons
	7	*
	8	* This file is licensed under the terms of the GNU General Public
	9	* License version 2. This program is licensed "as is" without any
	10	* warranty of any kind, whether express or implied.
	11	*/
	12
	13	#include <linux/io.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/printk.h>
	18
	19	#define AT91_SHDW_CR 0x00 /* Shut Down Control Register */
	20	#define AT91_SHDW_SHDW BIT(0) /* Shut Down command */
	21	#define AT91_SHDW_KEY (0xa5 << 24) /* KEY Password */
	22
	23	#define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */
	24	#define AT91_SHDW_WKMODE0 GENMASK(2, 0) /* Wake-up 0 Mode Selection */
	25	#define AT91_SHDW_CPTWK0_MAX 0xf /* Maximum Counter On Wake Up 0 */
	26	#define AT91_SHDW_CPTWK0 (AT91_SHDW_CPTWK0_MAX << 4) /* Counter On Wake Up 0 */
	27	#define AT91_SHDW_CPTWK0_(x) ((x) << 4)
	28	#define AT91_SHDW_RTTWKEN BIT(16) /* Real Time Timer Wake-up Enable */
	29	#define AT91_SHDW_RTCWKEN BIT(17) /* Real Time Clock Wake-up Enable */
	30
	31	#define AT91_SHDW_SR 0x08 /* Shut Down Status Register */
	32	#define AT91_SHDW_WAKEUP0 BIT(0) /* Wake-up 0 Status */
	33	#define AT91_SHDW_RTTWK BIT(16) /* Real-time Timer Wake-up */
	34	#define AT91_SHDW_RTCWK BIT(17) /* Real-time Clock Wake-up [SAM9RL] */
	35
	36	enum wakeup_type {
	37	AT91_SHDW_WKMODE0_NONE = 0,
	38	AT91_SHDW_WKMODE0_HIGH = 1,
	39	AT91_SHDW_WKMODE0_LOW = 2,
	40	AT91_SHDW_WKMODE0_ANYLEVEL = 3,
	41	};
	42
	43	static const char *shdwc_wakeup_modes[] = {
	44	[AT91_SHDW_WKMODE0_NONE] = "none",
	45	[AT91_SHDW_WKMODE0_HIGH] = "high",
	46	[AT91_SHDW_WKMODE0_LOW] = "low",
	47	[AT91_SHDW_WKMODE0_ANYLEVEL] = "any",
	48	};
	49
	50	static void __iomem *at91_shdwc_base;
	51
	52	static void __init at91_wakeup_status(void)
	53	{
405a72c5	54	u32 reg = readl(at91_shdwc_base + AT91_SHDW_SR);
ae499f0f MR	55	char *reason = "unknown";
	56
	57	/* Simple power-on, just bail out */
	58	if (!reg)
	59	return;
	60
	61	if (reg & AT91_SHDW_RTTWK)
	62	reason = "RTT";
	63	else if (reg & AT91_SHDW_RTCWK)
	64	reason = "RTC";
	65
	66	pr_info("AT91: Wake-Up source: %s\n", reason);
	67	}
	68
	69	static void at91_poweroff(void)
	70	{
	71	writel(AT91_SHDW_KEY \| AT91_SHDW_SHDW, at91_shdwc_base + AT91_SHDW_CR);
	72	}
	73
a538cf04	74	static int at91_poweroff_get_wakeup_mode(struct device_node *np)
ae499f0f MR	75	{
ae499f0f MR	76	const char *pm;
a538cf04 GR	77	unsigned int i;
a538cf04 GR	78	int err;
ae499f0f MR	79
	80	err = of_property_read_string(np, "atmel,wakeup-mode", &pm);
	81	if (err < 0)
	82	return AT91_SHDW_WKMODE0_ANYLEVEL;
	83
	84	for (i = 0; i < ARRAY_SIZE(shdwc_wakeup_modes); i++)
	85	if (!strcasecmp(pm, shdwc_wakeup_modes[i]))
	86	return i;
	87
	88	return -ENODEV;
	89	}
	90
	91	static void at91_poweroff_dt_set_wakeup_mode(struct platform_device *pdev)
	92	{
	93	struct device_node *np = pdev->dev.of_node;
a538cf04	94	int wakeup_mode;
ae499f0f MR	95	u32 mode = 0, tmp;
	96
	97	wakeup_mode = at91_poweroff_get_wakeup_mode(np);
	98	if (wakeup_mode < 0) {
	99	dev_warn(&pdev->dev, "shdwc unknown wakeup mode\n");
	100	return;
	101	}
	102
	103	if (!of_property_read_u32(np, "atmel,wakeup-counter", &tmp)) {
	104	if (tmp > AT91_SHDW_CPTWK0_MAX) {
	105	dev_warn(&pdev->dev,
	106	"shdwc wakeup counter 0x%x > 0x%x reduce it to 0x%x\n",
	107	tmp, AT91_SHDW_CPTWK0_MAX, AT91_SHDW_CPTWK0_MAX);
	108	tmp = AT91_SHDW_CPTWK0_MAX;
	109	}
	110	mode \|= AT91_SHDW_CPTWK0_(tmp);
	111	}
	112
	113	if (of_property_read_bool(np, "atmel,wakeup-rtc-timer"))
	114	mode \|= AT91_SHDW_RTCWKEN;
	115
	116	if (of_property_read_bool(np, "atmel,wakeup-rtt-timer"))
	117	mode \|= AT91_SHDW_RTTWKEN;
	118
	119	writel(wakeup_mode \| mode, at91_shdwc_base + AT91_SHDW_MR);
	120	}
	121
	122	static int at91_poweroff_probe(struct platform_device *pdev)
	123	{
	124	struct resource *res;
	125
	126	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	127	at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res);
	128	if (IS_ERR(at91_shdwc_base)) {
	129	dev_err(&pdev->dev, "Could not map reset controller address\n");
	130	return PTR_ERR(at91_shdwc_base);
	131	}
	132
	133	at91_wakeup_status();
	134
	135	if (pdev->dev.of_node)
	136	at91_poweroff_dt_set_wakeup_mode(pdev);
	137
	138	pm_power_off = at91_poweroff;
	139
	140	return 0;
	141	}
	142
8fb08855	143	static const struct of_device_id at91_poweroff_of_match[] = {
ae499f0f MR	144	{ .compatible = "atmel,at91sam9260-shdwc", },
	145	{ .compatible = "atmel,at91sam9rl-shdwc", },
	146	{ .compatible = "atmel,at91sam9x5-shdwc", },
	147	{ /sentinel/ }
	148	};
	149
	150	static struct platform_driver at91_poweroff_driver = {
	151	.probe = at91_poweroff_probe,
	152	.driver = {
	153	.name = "at91-poweroff",
	154	.of_match_table = at91_poweroff_of_match,
	155	},
	156	};
	157	module_platform_driver(at91_poweroff_driver);