[linux.git] / drivers / mfd / ab8500-gpadc.c

/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License Terms: GNU General Public License v2
 * Author: Arun R Murthy <[email protected]>
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/completion.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/mfd/ab8500.h>
#include <linux/mfd/abx500.h>
#include <linux/mfd/ab8500/ab8500-gpadc.h>

/*
 * GPADC register offsets
 * Bank : 0x0A
 */
#define AB8500_GPADC_CTRL1_REG		0x00
#define AB8500_GPADC_CTRL2_REG		0x01
#define AB8500_GPADC_CTRL3_REG		0x02
#define AB8500_GPADC_AUTO_TIMER_REG	0x03
#define AB8500_GPADC_STAT_REG		0x04
#define AB8500_GPADC_MANDATAL_REG	0x05
#define AB8500_GPADC_MANDATAH_REG	0x06
#define AB8500_GPADC_AUTODATAL_REG	0x07
#define AB8500_GPADC_AUTODATAH_REG	0x08
#define AB8500_GPADC_MUX_CTRL_REG	0x09

/* gpadc constants */
#define EN_VINTCORE12			0x04
#define EN_VTVOUT			0x02
#define EN_GPADC			0x01
#define DIS_GPADC			0x00
#define SW_AVG_16			0x60
#define ADC_SW_CONV			0x04
#define EN_BUF				0x40
#define DIS_ZERO			0x00
#define GPADC_BUSY			0x01

/**
 * struct ab8500_gpadc - ab8500 GPADC device information
 * @dev:			pointer to the struct device
 * @parent:			pointer to the parent device structure ab8500
 * @ab8500_gpadc_complete:	pointer to the struct completion, to indicate
 *				the completion of gpadc conversion
 * @ab8500_gpadc_lock:		structure of type mutex
 * @regu:			pointer to the struct regulator
 * @irq:			interrupt number that is used by gpadc
 */
static struct ab8500_gpadc {
	struct device *dev;
	struct ab8500 *parent;
	struct completion ab8500_gpadc_complete;
	struct mutex ab8500_gpadc_lock;
	struct regulator *regu;
	int irq;
} *di;

/**
 * ab8500_gpadc_convert() - gpadc conversion
 * @input:	analog input to be converted to digital data
 *
 * This function converts the selected analog i/p to digital
 * data. Thereafter calibration has to be made to obtain the
 * data in the required quantity measurement.
 */
int ab8500_gpadc_convert(u8 input)
{
	int ret;
	u16 data = 0;
	int looplimit = 0;
	u8 val, low_data, high_data;

	if (!di)
		return -ENODEV;

	mutex_lock(&di->ab8500_gpadc_lock);
	/* Enable VTVout LDO this is required for GPADC */
	regulator_enable(di->regu);

	/* Check if ADC is not busy, lock and proceed */
	do {
		ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
			AB8500_GPADC_STAT_REG, &val);
		if (ret < 0)
			goto out;
		if (!(val & GPADC_BUSY))
			break;
		msleep(10);
	} while (++looplimit < 10);
	if (looplimit >= 10 && (val & GPADC_BUSY)) {
		dev_err(di->dev, "gpadc_conversion: GPADC busy");
		ret = -EINVAL;
		goto out;
	}

	/* Enable GPADC */
	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL1_REG, EN_GPADC, EN_GPADC);
	if (ret < 0) {
		dev_err(di->dev, "gpadc_conversion: enable gpadc failed\n");
		goto out;
	}
	/* Select the input source and set average samples to 16 */
	ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL2_REG, (input | SW_AVG_16));
	if (ret < 0) {
		dev_err(di->dev,
			"gpadc_conversion: set avg samples failed\n");
		goto out;
	}
	/* Enable ADC, Buffering and select rising edge, start Conversion */
	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL1_REG, EN_BUF, EN_BUF);
	if (ret < 0) {
		dev_err(di->dev,
			"gpadc_conversion: select falling edge failed\n");
		goto out;
	}
	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL1_REG, ADC_SW_CONV, ADC_SW_CONV);
	if (ret < 0) {
		dev_err(di->dev,
			"gpadc_conversion: start s/w conversion failed\n");
		goto out;
	}
	/* wait for completion of conversion */
	if (!wait_for_completion_timeout(&di->ab8500_gpadc_complete, 2*HZ)) {
		dev_err(di->dev,
			"timeout: didnt recieve GPADC conversion interrupt\n");
		ret = -EINVAL;
		goto out;
	}

	/* Read the converted RAW data */
	ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_MANDATAL_REG, &low_data);
	if (ret < 0) {
		dev_err(di->dev, "gpadc_conversion: read low data failed\n");
		goto out;
	}

	ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_MANDATAH_REG, &high_data);
	if (ret < 0) {
		dev_err(di->dev, "gpadc_conversion: read high data failed\n");
		goto out;
	}

	data = (high_data << 8) | low_data;
	/* Disable GPADC */
	ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL1_REG, DIS_GPADC);
	if (ret < 0) {
		dev_err(di->dev, "gpadc_conversion: disable gpadc failed\n");
		goto out;
	}
	/* Disable VTVout LDO this is required for GPADC */
	regulator_disable(di->regu);
	mutex_unlock(&di->ab8500_gpadc_lock);
	return data;

out:
	/*
	 * It has shown to be needed to turn off the GPADC if an error occurs,
	 * otherwise we might have problem when waiting for the busy bit in the
	 * GPADC status register to go low. In V1.1 there wait_for_completion
	 * seems to timeout when waiting for an interrupt.. Not seen in V2.0
	 */
	(void) abx500_set_register_interruptible(di->dev, AB8500_GPADC,
		AB8500_GPADC_CTRL1_REG, DIS_GPADC);
	regulator_disable(di->regu);
	mutex_unlock(&di->ab8500_gpadc_lock);
	dev_err(di->dev, "gpadc_conversion: Failed to AD convert channel %d\n",
		input);
	return ret;
}
EXPORT_SYMBOL(ab8500_gpadc_convert);

/**
 * ab8500_bm_gpswadcconvend_handler() - isr for s/w gpadc conversion completion
 * @irq:	irq number
 * @data:	pointer to the data passed during request irq
 *
 * This is a interrupt service routine for s/w gpadc conversion completion.
 * Notifies the gpadc completion is completed and the converted raw value
 * can be read from the registers.
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_bm_gpswadcconvend_handler(int irq, void *_di)
{
	struct ab8500_gpadc *gpadc = _di;

	complete(&gpadc->ab8500_gpadc_complete);

	return IRQ_HANDLED;
}

static int __devinit ab8500_gpadc_probe(struct platform_device *pdev)
{
	int ret = 0;
	struct ab8500_gpadc *gpadc;

	gpadc = kzalloc(sizeof(struct ab8500_gpadc), GFP_KERNEL);
	if (!gpadc) {
		dev_err(&pdev->dev, "Error: No memory\n");
		return -ENOMEM;
	}

	gpadc->parent = dev_get_drvdata(pdev->dev.parent);
	gpadc->irq = platform_get_irq_byname(pdev, "SW_CONV_END");
	if (gpadc->irq < 0) {
		dev_err(gpadc->dev, "failed to get platform irq-%d\n", di->irq);
		ret = gpadc->irq;
		goto fail;
	}

	gpadc->dev = &pdev->dev;
	mutex_init(&di->ab8500_gpadc_lock);

	/* Initialize completion used to notify completion of conversion */
	init_completion(&gpadc->ab8500_gpadc_complete);

	/* Register interrupt  - SwAdcComplete */
	ret = request_threaded_irq(gpadc->irq, NULL,
		ab8500_bm_gpswadcconvend_handler,
		IRQF_NO_SUSPEND | IRQF_SHARED, "ab8500-gpadc", gpadc);
	if (ret < 0) {
		dev_err(gpadc->dev, "Failed to register interrupt, irq: %d\n",
			gpadc->irq);
		goto fail;
	}

	/* VTVout LDO used to power up ab8500-GPADC */
	gpadc->regu = regulator_get(&pdev->dev, "vddadc");
	if (IS_ERR(gpadc->regu)) {
		ret = PTR_ERR(gpadc->regu);
		dev_err(gpadc->dev, "failed to get vtvout LDO\n");
		goto fail;
	}
	di = gpadc;
	dev_dbg(gpadc->dev, "probe success\n");
	return 0;
fail:
	kfree(gpadc);
	gpadc = NULL;
	return ret;
}

static int __devexit ab8500_gpadc_remove(struct platform_device *pdev)
{
	struct ab8500_gpadc *gpadc = platform_get_drvdata(pdev);

	/* remove interrupt  - completion of Sw ADC conversion */
	free_irq(gpadc->irq, di);
	/* disable VTVout LDO that is being used by GPADC */
	regulator_put(gpadc->regu);
	kfree(gpadc);
	gpadc = NULL;
	return 0;
}

static struct platform_driver ab8500_gpadc_driver = {
	.probe = ab8500_gpadc_probe,
	.remove = __devexit_p(ab8500_gpadc_remove),
	.driver = {
		.name = "ab8500-gpadc",
		.owner = THIS_MODULE,
	},
};

static int __init ab8500_gpadc_init(void)
{
	return platform_driver_register(&ab8500_gpadc_driver);
}

static void __exit ab8500_gpadc_exit(void)
{
	platform_driver_unregister(&ab8500_gpadc_driver);
}

subsys_initcall_sync(ab8500_gpadc_init);
module_exit(ab8500_gpadc_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Arun R Murthy");
MODULE_ALIAS("platform:ab8500_gpadc");
MODULE_DESCRIPTION("AB8500 GPADC driver");
Commit	Line	Data
dae2db30 AM	1	/*
	2	* Copyright (C) ST-Ericsson SA 2010
	3	*
	4	* License Terms: GNU General Public License v2
	5	* Author: Arun R Murthy <[email protected]>
	6	*/
	7	#include <linux/init.h>
	8	#include <linux/module.h>
	9	#include <linux/device.h>
	10	#include <linux/interrupt.h>
	11	#include <linux/spinlock.h>
	12	#include <linux/delay.h>
	13	#include <linux/platform_device.h>
	14	#include <linux/completion.h>
	15	#include <linux/regulator/consumer.h>
	16	#include <linux/err.h>
	17	#include <linux/slab.h>
	18	#include <linux/mfd/ab8500.h>
	19	#include <linux/mfd/abx500.h>
cf169439	20	#include <linux/mfd/ab8500/ab8500-gpadc.h>
dae2db30 AM	21
	22	/*
	23	* GPADC register offsets
	24	* Bank : 0x0A
	25	*/
	26	#define AB8500_GPADC_CTRL1_REG 0x00
	27	#define AB8500_GPADC_CTRL2_REG 0x01
	28	#define AB8500_GPADC_CTRL3_REG 0x02
	29	#define AB8500_GPADC_AUTO_TIMER_REG 0x03
	30	#define AB8500_GPADC_STAT_REG 0x04
	31	#define AB8500_GPADC_MANDATAL_REG 0x05
	32	#define AB8500_GPADC_MANDATAH_REG 0x06
	33	#define AB8500_GPADC_AUTODATAL_REG 0x07
	34	#define AB8500_GPADC_AUTODATAH_REG 0x08
	35	#define AB8500_GPADC_MUX_CTRL_REG 0x09
	36
	37	/* gpadc constants */
	38	#define EN_VINTCORE12 0x04
	39	#define EN_VTVOUT 0x02
	40	#define EN_GPADC 0x01
	41	#define DIS_GPADC 0x00
	42	#define SW_AVG_16 0x60
	43	#define ADC_SW_CONV 0x04
	44	#define EN_BUF 0x40
	45	#define DIS_ZERO 0x00
	46	#define GPADC_BUSY 0x01
	47
	48	/**
	49	* struct ab8500_gpadc - ab8500 GPADC device information
	50	* @dev: pointer to the struct device
	51	* @parent: pointer to the parent device structure ab8500
	52	* @ab8500_gpadc_complete: pointer to the struct completion, to indicate
	53	* the completion of gpadc conversion
	54	* @ab8500_gpadc_lock: structure of type mutex
	55	* @regu: pointer to the struct regulator
	56	* @irq: interrupt number that is used by gpadc
	57	*/
	58	static struct ab8500_gpadc {
	59	struct device *dev;
	60	struct ab8500 *parent;
	61	struct completion ab8500_gpadc_complete;
	62	struct mutex ab8500_gpadc_lock;
	63	struct regulator *regu;
	64	int irq;
	65	} *di;
	66
	67	/**
	68	* ab8500_gpadc_convert() - gpadc conversion
	69	* @input: analog input to be converted to digital data
	70	*
	71	* This function converts the selected analog i/p to digital
	72	* data. Thereafter calibration has to be made to obtain the
	73	* data in the required quantity measurement.
	74	*/
	75	int ab8500_gpadc_convert(u8 input)
	76	{
	77	int ret;
	78	u16 data = 0;
	79	int looplimit = 0;
	80	u8 val, low_data, high_data;
	81
	82	if (!di)
	83	return -ENODEV;
	84
85	mutex_lock(&di->ab8500_gpadc_lock);
86	/* Enable VTVout LDO this is required for GPADC */
87	regulator_enable(di->regu);
88
89	/* Check if ADC is not busy, lock and proceed */
90	do {
91	ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
92	AB8500_GPADC_STAT_REG, &val);
93	if (ret < 0)
94	goto out;
95	if (!(val & GPADC_BUSY))
96	break;
97	msleep(10);
98	} while (++looplimit < 10);
99	if (looplimit >= 10 && (val & GPADC_BUSY)) {
100	dev_err(di->dev, "gpadc_conversion: GPADC busy");
101	ret = -EINVAL;
102	goto out;
103	}
104
105	/* Enable GPADC */
106	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
107	AB8500_GPADC_CTRL1_REG, EN_GPADC, EN_GPADC);
108	if (ret < 0) {
109	dev_err(di->dev, "gpadc_conversion: enable gpadc failed\n");
110	goto out;
111	}
112	/* Select the input source and set average samples to 16 */
113	ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC,
114	AB8500_GPADC_CTRL2_REG, (input \| SW_AVG_16));
115	if (ret < 0) {
116	dev_err(di->dev,
117	"gpadc_conversion: set avg samples failed\n");
118	goto out;
119	}
120	/* Enable ADC, Buffering and select rising edge, start Conversion */
121	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
122	AB8500_GPADC_CTRL1_REG, EN_BUF, EN_BUF);
123	if (ret < 0) {
124	dev_err(di->dev,
125	"gpadc_conversion: select falling edge failed\n");
126	goto out;
127	}
128	ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC,
129	AB8500_GPADC_CTRL1_REG, ADC_SW_CONV, ADC_SW_CONV);
130	if (ret < 0) {
131	dev_err(di->dev,
132	"gpadc_conversion: start s/w conversion failed\n");
133	goto out;
134	}
135	/* wait for completion of conversion */
136	if (!wait_for_completion_timeout(&di->ab8500_gpadc_complete, 2*HZ)) {
137	dev_err(di->dev,
138	"timeout: didnt recieve GPADC conversion interrupt\n");
139	ret = -EINVAL;
140	goto out;
141	}
142
143	/* Read the converted RAW data */
144	ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
145	AB8500_GPADC_MANDATAL_REG, &low_data);
146	if (ret < 0) {
147	dev_err(di->dev, "gpadc_conversion: read low data failed\n");
148	goto out;
149	}
150
151	ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC,
152	AB8500_GPADC_MANDATAH_REG, &high_data);
153	if (ret < 0) {
154	dev_err(di->dev, "gpadc_conversion: read high data failed\n");
155	goto out;
156	}
157
158	data = (high_data << 8) \| low_data;
159	/* Disable GPADC */
160	ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC,
161	AB8500_GPADC_CTRL1_REG, DIS_GPADC);
162	if (ret < 0) {
163	dev_err(di->dev, "gpadc_conversion: disable gpadc failed\n");
164	goto out;
165	}
166	/* Disable VTVout LDO this is required for GPADC */
167	regulator_disable(di->regu);
168	mutex_unlock(&di->ab8500_gpadc_lock);
169	return data;
170
171	out:
172	/*
173	* It has shown to be needed to turn off the GPADC if an error occurs,
174	* otherwise we might have problem when waiting for the busy bit in the
175	* GPADC status register to go low. In V1.1 there wait_for_completion
176	* seems to timeout when waiting for an interrupt.. Not seen in V2.0
177	*/
178	(void) abx500_set_register_interruptible(di->dev, AB8500_GPADC,
179	AB8500_GPADC_CTRL1_REG, DIS_GPADC);
180	regulator_disable(di->regu);
181	mutex_unlock(&di->ab8500_gpadc_lock);
182	dev_err(di->dev, "gpadc_conversion: Failed to AD convert channel %d\n",
183	input);
184	return ret;
185	}
186	EXPORT_SYMBOL(ab8500_gpadc_convert);
187
188	/**
189	* ab8500_bm_gpswadcconvend_handler() - isr for s/w gpadc conversion completion
190	* @irq: irq number
191	* @data: pointer to the data passed during request irq
192	*
193	* This is a interrupt service routine for s/w gpadc conversion completion.
194	* Notifies the gpadc completion is completed and the converted raw value
195	* can be read from the registers.
196	* Returns IRQ status(IRQ_HANDLED)
197	*/
198	static irqreturn_t ab8500_bm_gpswadcconvend_handler(int irq, void *_di)
199	{
200	struct ab8500_gpadc *gpadc = _di;
201
202	complete(&gpadc->ab8500_gpadc_complete);
203
204	return IRQ_HANDLED;
205	}
206
207	static int __devinit ab8500_gpadc_probe(struct platform_device *pdev)
208	{
209	int ret = 0;
210	struct ab8500_gpadc *gpadc;
211
212	gpadc = kzalloc(sizeof(struct ab8500_gpadc), GFP_KERNEL);
213	if (!gpadc) {
214	dev_err(&pdev->dev, "Error: No memory\n");
215	return -ENOMEM;
216	}
217
218	gpadc->parent = dev_get_drvdata(pdev->dev.parent);
219	gpadc->irq = platform_get_irq_byname(pdev, "SW_CONV_END");
220	if (gpadc->irq < 0) {
221	dev_err(gpadc->dev, "failed to get platform irq-%d\n", di->irq);
222	ret = gpadc->irq;
223	goto fail;
224	}
225
226	gpadc->dev = &pdev->dev;
227	mutex_init(&di->ab8500_gpadc_lock);
228
229	/* Initialize completion used to notify completion of conversion */
230	init_completion(&gpadc->ab8500_gpadc_complete);
231
232	/* Register interrupt - SwAdcComplete */
233	ret = request_threaded_irq(gpadc->irq, NULL,
234	ab8500_bm_gpswadcconvend_handler,
235	IRQF_NO_SUSPEND \| IRQF_SHARED, "ab8500-gpadc", gpadc);
236	if (ret < 0) {
237	dev_err(gpadc->dev, "Failed to register interrupt, irq: %d\n",
238	gpadc->irq);
239	goto fail;
240	}
241
242	/* VTVout LDO used to power up ab8500-GPADC */
243	gpadc->regu = regulator_get(&pdev->dev, "vddadc");
244	if (IS_ERR(gpadc->regu)) {
245	ret = PTR_ERR(gpadc->regu);
246	dev_err(gpadc->dev, "failed to get vtvout LDO\n");
247	goto fail;
248	}
249	di = gpadc;
250	dev_dbg(gpadc->dev, "probe success\n");
251	return 0;
252	fail:
253	kfree(gpadc);
254	gpadc = NULL;
255	return ret;
256	}
257
258	static int __devexit ab8500_gpadc_remove(struct platform_device *pdev)
259	{
260	struct ab8500_gpadc *gpadc = platform_get_drvdata(pdev);
261
262	/* remove interrupt - completion of Sw ADC conversion */
263	free_irq(gpadc->irq, di);
264	/* disable VTVout LDO that is being used by GPADC */
265	regulator_put(gpadc->regu);
266	kfree(gpadc);
267	gpadc = NULL;
268	return 0;
269	}
270
271	static struct platform_driver ab8500_gpadc_driver = {
272	.probe = ab8500_gpadc_probe,
273	.remove = __devexit_p(ab8500_gpadc_remove),
274	.driver = {
275	.name = "ab8500-gpadc",
276	.owner = THIS_MODULE,
277	},
278	};
279
280	static int __init ab8500_gpadc_init(void)
281	{
282	return platform_driver_register(&ab8500_gpadc_driver);
283	}
284
285	static void __exit ab8500_gpadc_exit(void)
286	{
287	platform_driver_unregister(&ab8500_gpadc_driver);
288	}
289
290	subsys_initcall_sync(ab8500_gpadc_init);
291	module_exit(ab8500_gpadc_exit);
292
293	MODULE_LICENSE("GPL v2");
294	MODULE_AUTHOR("Arun R Murthy");
295	MODULE_ALIAS("platform:ab8500_gpadc");
296	MODULE_DESCRIPTION("AB8500 GPADC driver");