[linux-2.6-block.git] / drivers / power / wm831x_backup.c

/*
 * Backup battery driver for Wolfson Microelectronics wm831x PMICs
 *
 * Copyright 2009 Wolfson Microelectronics PLC.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/auxadc.h>
#include <linux/mfd/wm831x/pmu.h>
#include <linux/mfd/wm831x/pdata.h>

struct wm831x_backup {
	struct wm831x *wm831x;
	struct power_supply backup;
};

static int wm831x_backup_read_voltage(struct wm831x *wm831x,
				     enum wm831x_auxadc src,
				     union power_supply_propval *val)
{
	int ret;

	ret = wm831x_auxadc_read_uv(wm831x, src);
	if (ret >= 0)
		val->intval = ret;

	return ret;
}

/*********************************************************************
 *		Backup supply properties
 *********************************************************************/

static void wm831x_config_backup(struct wm831x *wm831x)
{
	struct wm831x_pdata *wm831x_pdata = wm831x->dev->platform_data;
	struct wm831x_backup_pdata *pdata;
	int ret, reg;

	if (!wm831x_pdata || !wm831x_pdata->backup) {
		dev_warn(wm831x->dev,
			 "No backup battery charger configuration\n");
		return;
	}

	pdata = wm831x_pdata->backup;

	reg = 0;

	if (pdata->charger_enable)
		reg |= WM831X_BKUP_CHG_ENA | WM831X_BKUP_BATT_DET_ENA;
	if (pdata->no_constant_voltage)
		reg |= WM831X_BKUP_CHG_MODE;

	switch (pdata->vlim) {
	case 2500:
		break;
	case 3100:
		reg |= WM831X_BKUP_CHG_VLIM;
		break;
	default:
		dev_err(wm831x->dev, "Invalid backup voltage limit %dmV\n",
			pdata->vlim);
	}

	switch (pdata->ilim) {
	case 100:
		break;
	case 200:
		reg |= 1;
		break;
	case 300:
		reg |= 2;
		break;
	case 400:
		reg |= 3;
		break;
	default:
		dev_err(wm831x->dev, "Invalid backup current limit %duA\n",
			pdata->ilim);
	}

	ret = wm831x_reg_unlock(wm831x);
	if (ret != 0) {
		dev_err(wm831x->dev, "Failed to unlock registers: %d\n", ret);
		return;
	}

	ret = wm831x_set_bits(wm831x, WM831X_BACKUP_CHARGER_CONTROL,
			      WM831X_BKUP_CHG_ENA_MASK |
			      WM831X_BKUP_CHG_MODE_MASK |
			      WM831X_BKUP_BATT_DET_ENA_MASK |
			      WM831X_BKUP_CHG_VLIM_MASK |
			      WM831X_BKUP_CHG_ILIM_MASK,
			      reg);
	if (ret != 0)
		dev_err(wm831x->dev,
			"Failed to set backup charger config: %d\n", ret);

	wm831x_reg_lock(wm831x);
}

static int wm831x_backup_get_prop(struct power_supply *psy,
				  enum power_supply_property psp,
				  union power_supply_propval *val)
{
	struct wm831x_backup *devdata = dev_get_drvdata(psy->dev->parent);
	struct wm831x *wm831x = devdata->wm831x;
	int ret = 0;

	ret = wm831x_reg_read(wm831x, WM831X_BACKUP_CHARGER_CONTROL);
	if (ret < 0)
		return ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		if (ret & WM831X_BKUP_CHG_STS)
			val->intval = POWER_SUPPLY_STATUS_CHARGING;
		else
			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
		break;

	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		ret = wm831x_backup_read_voltage(wm831x, WM831X_AUX_BKUP_BATT,
						val);
		break;

	case POWER_SUPPLY_PROP_PRESENT:
		if (ret & WM831X_BKUP_CHG_STS)
			val->intval = 1;
		else
			val->intval = 0;
		break;

	default:
		ret = -EINVAL;
		break;
	}

	return ret;
}

static enum power_supply_property wm831x_backup_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_PRESENT,
};

/*********************************************************************
 *		Initialisation
 *********************************************************************/

static __devinit int wm831x_backup_probe(struct platform_device *pdev)
{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_backup *devdata;
	struct power_supply *backup;
	int ret;

	devdata = kzalloc(sizeof(struct wm831x_backup), GFP_KERNEL);
	if (devdata == NULL)
		return -ENOMEM;

	devdata->wm831x = wm831x;
	platform_set_drvdata(pdev, devdata);

	backup = &devdata->backup;

	/* We ignore configuration failures since we can still read
	 * back the status without enabling the charger (which may
	 * already be enabled anyway).
	 */
	wm831x_config_backup(wm831x);

	backup->name = "wm831x-backup";
	backup->type = POWER_SUPPLY_TYPE_BATTERY;
	backup->properties = wm831x_backup_props;
	backup->num_properties = ARRAY_SIZE(wm831x_backup_props);
	backup->get_property = wm831x_backup_get_prop;
	ret = power_supply_register(&pdev->dev, backup);
	if (ret)
		goto err_kmalloc;

	return ret;

err_kmalloc:
	kfree(devdata);
	return ret;
}

static __devexit int wm831x_backup_remove(struct platform_device *pdev)
{
	struct wm831x_backup *devdata = platform_get_drvdata(pdev);

	power_supply_unregister(&devdata->backup);
	kfree(devdata);

	return 0;
}

static struct platform_driver wm831x_backup_driver = {
	.probe = wm831x_backup_probe,
	.remove = __devexit_p(wm831x_backup_remove),
	.driver = {
		.name = "wm831x-backup",
	},
};

static int __init wm831x_backup_init(void)
{
	return platform_driver_register(&wm831x_backup_driver);
}
module_init(wm831x_backup_init);

static void __exit wm831x_backup_exit(void)
{
	platform_driver_unregister(&wm831x_backup_driver);
}
module_exit(wm831x_backup_exit);

MODULE_DESCRIPTION("Backup battery charger driver for WM831x PMICs");
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-backup");
Commit	Line	Data
c26964ea MB	1	/*
	2	* Backup battery driver for Wolfson Microelectronics wm831x PMICs
	3	*
	4	* Copyright 2009 Wolfson Microelectronics PLC.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/module.h>
	12	#include <linux/err.h>
	13	#include <linux/platform_device.h>
	14	#include <linux/power_supply.h>
5a0e3ad6	15	#include <linux/slab.h>
c26964ea MB	16
	17	#include <linux/mfd/wm831x/core.h>
	18	#include <linux/mfd/wm831x/auxadc.h>
	19	#include <linux/mfd/wm831x/pmu.h>
	20	#include <linux/mfd/wm831x/pdata.h>
	21
	22	struct wm831x_backup {
	23	struct wm831x *wm831x;
	24	struct power_supply backup;
	25	};
	26
	27	static int wm831x_backup_read_voltage(struct wm831x *wm831x,
	28	enum wm831x_auxadc src,
	29	union power_supply_propval *val)
	30	{
	31	int ret;
	32
	33	ret = wm831x_auxadc_read_uv(wm831x, src);
	34	if (ret >= 0)
	35	val->intval = ret;
	36
	37	return ret;
	38	}
	39
	40	/*********************************************************************
	41	* Backup supply properties
	42	*********************************************************************/
	43
	44	static void wm831x_config_backup(struct wm831x *wm831x)
	45	{
	46	struct wm831x_pdata *wm831x_pdata = wm831x->dev->platform_data;
	47	struct wm831x_backup_pdata *pdata;
	48	int ret, reg;
	49
	50	if (!wm831x_pdata \|\| !wm831x_pdata->backup) {
	51	dev_warn(wm831x->dev,
	52	"No backup battery charger configuration\n");
	53	return;
	54	}
	55
	56	pdata = wm831x_pdata->backup;
	57
	58	reg = 0;
	59
	60	if (pdata->charger_enable)
	61	reg \|= WM831X_BKUP_CHG_ENA \| WM831X_BKUP_BATT_DET_ENA;
	62	if (pdata->no_constant_voltage)
	63	reg \|= WM831X_BKUP_CHG_MODE;
	64
	65	switch (pdata->vlim) {
	66	case 2500:
	67	break;
	68	case 3100:
	69	reg \|= WM831X_BKUP_CHG_VLIM;
	70	break;
	71	default:
	72	dev_err(wm831x->dev, "Invalid backup voltage limit %dmV\n",
	73	pdata->vlim);
	74	}
	75
	76	switch (pdata->ilim) {
	77	case 100:
	78	break;
	79	case 200:
80	reg \|= 1;
81	break;
82	case 300:
83	reg \|= 2;
84	break;
85	case 400:
86	reg \|= 3;
87	break;
88	default:
89	dev_err(wm831x->dev, "Invalid backup current limit %duA\n",
90	pdata->ilim);
91	}
92
93	ret = wm831x_reg_unlock(wm831x);
94	if (ret != 0) {
95	dev_err(wm831x->dev, "Failed to unlock registers: %d\n", ret);
96	return;
97	}
98
99	ret = wm831x_set_bits(wm831x, WM831X_BACKUP_CHARGER_CONTROL,
100	WM831X_BKUP_CHG_ENA_MASK \|
101	WM831X_BKUP_CHG_MODE_MASK \|
102	WM831X_BKUP_BATT_DET_ENA_MASK \|
103	WM831X_BKUP_CHG_VLIM_MASK \|
104	WM831X_BKUP_CHG_ILIM_MASK,
105	reg);
106	if (ret != 0)
107	dev_err(wm831x->dev,
108	"Failed to set backup charger config: %d\n", ret);
109
110	wm831x_reg_lock(wm831x);
111	}
112
113	static int wm831x_backup_get_prop(struct power_supply *psy,
114	enum power_supply_property psp,
115	union power_supply_propval *val)
116	{
117	struct wm831x_backup *devdata = dev_get_drvdata(psy->dev->parent);
118	struct wm831x *wm831x = devdata->wm831x;
119	int ret = 0;
120
121	ret = wm831x_reg_read(wm831x, WM831X_BACKUP_CHARGER_CONTROL);
122	if (ret < 0)
123	return ret;
124
125	switch (psp) {
126	case POWER_SUPPLY_PROP_STATUS:
127	if (ret & WM831X_BKUP_CHG_STS)
128	val->intval = POWER_SUPPLY_STATUS_CHARGING;
129	else
130	val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
131	break;
132
133	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
134	ret = wm831x_backup_read_voltage(wm831x, WM831X_AUX_BKUP_BATT,
135	val);
136	break;
137
138	case POWER_SUPPLY_PROP_PRESENT:
139	if (ret & WM831X_BKUP_CHG_STS)
140	val->intval = 1;
141	else
142	val->intval = 0;
143	break;
144
145	default:
146	ret = -EINVAL;
147	break;
148	}
149
150	return ret;
151	}
152
153	static enum power_supply_property wm831x_backup_props[] = {
154	POWER_SUPPLY_PROP_STATUS,
155	POWER_SUPPLY_PROP_VOLTAGE_NOW,
156	POWER_SUPPLY_PROP_PRESENT,
157	};
158
159	/*********************************************************************
160	* Initialisation
161	*********************************************************************/
162
163	static __devinit int wm831x_backup_probe(struct platform_device *pdev)
164	{
165	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
166	struct wm831x_backup *devdata;
167	struct power_supply *backup;
0e19dbb7	168	int ret;
c26964ea MB	169
	170	devdata = kzalloc(sizeof(struct wm831x_backup), GFP_KERNEL);
	171	if (devdata == NULL)
	172	return -ENOMEM;
	173
	174	devdata->wm831x = wm831x;
	175	platform_set_drvdata(pdev, devdata);
	176
	177	backup = &devdata->backup;
	178
	179	/* We ignore configuration failures since we can still read
	180	* back the status without enabling the charger (which may
	181	* already be enabled anyway).
	182	*/
	183	wm831x_config_backup(wm831x);
	184
	185	backup->name = "wm831x-backup";
	186	backup->type = POWER_SUPPLY_TYPE_BATTERY;
	187	backup->properties = wm831x_backup_props;
	188	backup->num_properties = ARRAY_SIZE(wm831x_backup_props);
	189	backup->get_property = wm831x_backup_get_prop;
	190	ret = power_supply_register(&pdev->dev, backup);
	191	if (ret)
	192	goto err_kmalloc;
	193
	194	return ret;
	195
	196	err_kmalloc:
	197	kfree(devdata);
	198	return ret;
	199	}
	200
	201	static __devexit int wm831x_backup_remove(struct platform_device *pdev)
	202	{
	203	struct wm831x_backup *devdata = platform_get_drvdata(pdev);
	204
	205	power_supply_unregister(&devdata->backup);
	206	kfree(devdata);
	207
	208	return 0;
	209	}
	210
	211	static struct platform_driver wm831x_backup_driver = {
	212	.probe = wm831x_backup_probe,
	213	.remove = __devexit_p(wm831x_backup_remove),
	214	.driver = {
	215	.name = "wm831x-backup",
	216	},
	217	};
	218
	219	static int __init wm831x_backup_init(void)
	220	{
	221	return platform_driver_register(&wm831x_backup_driver);
	222	}
	223	module_init(wm831x_backup_init);
	224
	225	static void __exit wm831x_backup_exit(void)
	226	{
	227	platform_driver_unregister(&wm831x_backup_driver);
	228	}
	229	module_exit(wm831x_backup_exit);
	230
	231	MODULE_DESCRIPTION("Backup battery charger driver for WM831x PMICs");
	232	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
233	MODULE_LICENSE("GPL");
234	MODULE_ALIAS("platform:wm831x-backup");