[mirror_ubuntu-artful-kernel.git] / drivers / mfd / mc13xxx-spi.c

/*
 * Copyright 2009-2010 Pengutronix
 * Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
 *
 * loosely based on an earlier driver that has
 * Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
 *
 * 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/slab.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/mfd/core.h>
#include <linux/mfd/mc13xxx.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/err.h>
#include <linux/spi/spi.h>

#include "mc13xxx.h"

static const struct spi_device_id mc13xxx_device_id[] = {
	{
		.name = "mc13783",
		.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13783,
	}, {
		.name = "mc13892",
		.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13892,
	}, {
		.name = "mc34708",
		.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc34708,
	}, {
		/* sentinel */
	}
};
MODULE_DEVICE_TABLE(spi, mc13xxx_device_id);

static const struct of_device_id mc13xxx_dt_ids[] = {
	{ .compatible = "fsl,mc13783", .data = &mc13xxx_variant_mc13783, },
	{ .compatible = "fsl,mc13892", .data = &mc13xxx_variant_mc13892, },
	{ .compatible = "fsl,mc34708", .data = &mc13xxx_variant_mc34708, },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);

static struct regmap_config mc13xxx_regmap_spi_config = {
	.reg_bits = 7,
	.pad_bits = 1,
	.val_bits = 24,
	.write_flag_mask = 0x80,

	.max_register = MC13XXX_NUMREGS,

	.cache_type = REGCACHE_NONE,
	.use_single_rw = 1,
};

static int mc13xxx_spi_read(void *context, const void *reg, size_t reg_size,
				void *val, size_t val_size)
{
	unsigned char w[4] = { *((unsigned char *) reg), 0, 0, 0};
	unsigned char r[4];
	unsigned char *p = val;
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);
	struct spi_transfer t = {
		.tx_buf = w,
		.rx_buf = r,
		.len = 4,
	};

	struct spi_message m;
	int ret;

	if (val_size != 3 || reg_size != 1)
		return -ENOTSUPP;

	spi_message_init(&m);
	spi_message_add_tail(&t, &m);
	ret = spi_sync(spi, &m);

	memcpy(p, &r[1], 3);

	return ret;
}

static int mc13xxx_spi_write(void *context, const void *data, size_t count)
{
	struct device *dev = context;
	struct spi_device *spi = to_spi_device(dev);
	const char *reg = data;

	if (count != 4)
		return -ENOTSUPP;

	/* include errata fix for spi audio problems */
	if (*reg == MC13783_AUDIO_CODEC || *reg == MC13783_AUDIO_DAC)
		spi_write(spi, data, count);

	return spi_write(spi, data, count);
}

/*
 * We cannot use regmap-spi generic bus implementation here.
 * The MC13783 chip will get corrupted if CS signal is deasserted
 * and on i.Mx31 SoC (the target SoC for MC13783 PMIC) the SPI controller
 * has the following errata (DSPhl22960):
 * "The CSPI negates SS when the FIFO becomes empty with
 * SSCTL= 0. Software cannot guarantee that the FIFO will not
 * drain because of higher priority interrupts and the
 * non-realtime characteristics of the operating system. As a
 * result, the SS will negate before all of the data has been
 * transferred to/from the peripheral."
 * We workaround this by accessing the SPI controller with a
 * single transfert.
 */

static struct regmap_bus regmap_mc13xxx_bus = {
	.write = mc13xxx_spi_write,
	.read = mc13xxx_spi_read,
};

static int mc13xxx_spi_probe(struct spi_device *spi)
{
	struct mc13xxx *mc13xxx;
	struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
	int ret;

	mc13xxx = devm_kzalloc(&spi->dev, sizeof(*mc13xxx), GFP_KERNEL);
	if (!mc13xxx)
		return -ENOMEM;

	spi_set_drvdata(spi, mc13xxx);
	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;

	mc13xxx->dev = &spi->dev;
	mutex_init(&mc13xxx->lock);

	mc13xxx->regmap = devm_regmap_init(&spi->dev, &regmap_mc13xxx_bus,
					   &spi->dev,
					   &mc13xxx_regmap_spi_config);
	if (IS_ERR(mc13xxx->regmap)) {
		ret = PTR_ERR(mc13xxx->regmap);
		dev_err(mc13xxx->dev, "Failed to initialize register map: %d\n",
				ret);
		return ret;
	}

	if (spi->dev.of_node) {
		const struct of_device_id *of_id =
			of_match_device(mc13xxx_dt_ids, &spi->dev);

		mc13xxx->variant = of_id->data;
	} else {
		const struct spi_device_id *id_entry = spi_get_device_id(spi);

		mc13xxx->variant = (void *)id_entry->driver_data;
	}

	return mc13xxx_common_init(mc13xxx, pdata, spi->irq);
}

static int mc13xxx_spi_remove(struct spi_device *spi)
{
	struct mc13xxx *mc13xxx = spi_get_drvdata(spi);

	mc13xxx_common_cleanup(mc13xxx);

	return 0;
}

static struct spi_driver mc13xxx_spi_driver = {
	.id_table = mc13xxx_device_id,
	.driver = {
		.name = "mc13xxx",
		.owner = THIS_MODULE,
		.of_match_table = mc13xxx_dt_ids,
	},
	.probe = mc13xxx_spi_probe,
	.remove = mc13xxx_spi_remove,
};

static int __init mc13xxx_init(void)
{
	return spi_register_driver(&mc13xxx_spi_driver);
}
subsys_initcall(mc13xxx_init);

static void __exit mc13xxx_exit(void)
{
	spi_unregister_driver(&mc13xxx_spi_driver);
}
module_exit(mc13xxx_exit);

MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
a0c7c1d4 MR	1	/*
	2	* Copyright 2009-2010 Pengutronix
	3	* Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
	4	*
	5	* loosely based on an earlier driver that has
	6	* Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
	7	*
	8	* This program is free software; you can redistribute it and/or modify it under
	9	* the terms of the GNU General Public License version 2 as published by the
	10	* Free Software Foundation.
	11	*/
	12
	13	#include <linux/slab.h>
	14	#include <linux/module.h>
	15	#include <linux/platform_device.h>
	16	#include <linux/mutex.h>
	17	#include <linux/interrupt.h>
	18	#include <linux/mfd/core.h>
	19	#include <linux/mfd/mc13xxx.h>
	20	#include <linux/of.h>
	21	#include <linux/of_device.h>
	22	#include <linux/of_gpio.h>
	23	#include <linux/err.h>
	24	#include <linux/spi/spi.h>
	25
	26	#include "mc13xxx.h"
	27
	28	static const struct spi_device_id mc13xxx_device_id[] = {
	29	{
	30	.name = "mc13783",
cd0f34b0	31	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13783,
a0c7c1d4 MR	32	}, {
a0c7c1d4 MR	33	.name = "mc13892",
cd0f34b0	34	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13892,
0312e024 UKK	35	}, {
	36	.name = "mc34708",
	37	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc34708,
a0c7c1d4 MR	38	}, {
	39	/* sentinel */
	40	}
	41	};
	42	MODULE_DEVICE_TABLE(spi, mc13xxx_device_id);
	43
	44	static const struct of_device_id mc13xxx_dt_ids[] = {
cd0f34b0 UKK	45	{ .compatible = "fsl,mc13783", .data = &mc13xxx_variant_mc13783, },
cd0f34b0 UKK	46	{ .compatible = "fsl,mc13892", .data = &mc13xxx_variant_mc13892, },
0312e024	47	{ .compatible = "fsl,mc34708", .data = &mc13xxx_variant_mc34708, },
a0c7c1d4 MR	48	{ /* sentinel */ }
	49	};
	50	MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);
	51
	52	static struct regmap_config mc13xxx_regmap_spi_config = {
	53	.reg_bits = 7,
	54	.pad_bits = 1,
	55	.val_bits = 24,
77a5b370	56	.write_flag_mask = 0x80,
a0c7c1d4 MR	57
	58	.max_register = MC13XXX_NUMREGS,
	59
	60	.cache_type = REGCACHE_NONE,
e4ecf6ea PR	61	.use_single_rw = 1,
	62	};
	63
	64	static int mc13xxx_spi_read(void context, const void reg, size_t reg_size,
	65	void *val, size_t val_size)
	66	{
	67	unsigned char w[4] = { ((unsigned char ) reg), 0, 0, 0};
	68	unsigned char r[4];
	69	unsigned char *p = val;
	70	struct device *dev = context;
	71	struct spi_device *spi = to_spi_device(dev);
	72	struct spi_transfer t = {
	73	.tx_buf = w,
	74	.rx_buf = r,
	75	.len = 4,
	76	};
	77
	78	struct spi_message m;
	79	int ret;
	80
	81	if (val_size != 3 \|\| reg_size != 1)
	82	return -ENOTSUPP;
	83
	84	spi_message_init(&m);
	85	spi_message_add_tail(&t, &m);
	86	ret = spi_sync(spi, &m);
	87
	88	memcpy(p, &r[1], 3);
	89
	90	return ret;
	91	}
	92
	93	static int mc13xxx_spi_write(void context, const void data, size_t count)
	94	{
	95	struct device *dev = context;
	96	struct spi_device *spi = to_spi_device(dev);
fd792f8f	97	const char *reg = data;
e4ecf6ea PR	98
	99	if (count != 4)
	100	return -ENOTSUPP;
	101
fd792f8f MB	102	/* include errata fix for spi audio problems */
	103	if (reg == MC13783_AUDIO_CODEC \|\| reg == MC13783_AUDIO_DAC)
	104	spi_write(spi, data, count);
	105
e4ecf6ea PR	106	return spi_write(spi, data, count);
	107	}
	108
	109	/*
	110	* We cannot use regmap-spi generic bus implementation here.
	111	* The MC13783 chip will get corrupted if CS signal is deasserted
	112	* and on i.Mx31 SoC (the target SoC for MC13783 PMIC) the SPI controller
	113	* has the following errata (DSPhl22960):
	114	* "The CSPI negates SS when the FIFO becomes empty with
	115	* SSCTL= 0. Software cannot guarantee that the FIFO will not
	116	* drain because of higher priority interrupts and the
	117	* non-realtime characteristics of the operating system. As a
	118	* result, the SS will negate before all of the data has been
	119	* transferred to/from the peripheral."
	120	* We workaround this by accessing the SPI controller with a
	121	* single transfert.
	122	*/
	123
	124	static struct regmap_bus regmap_mc13xxx_bus = {
	125	.write = mc13xxx_spi_write,
	126	.read = mc13xxx_spi_read,
a0c7c1d4 MR	127	};
	128
	129	static int mc13xxx_spi_probe(struct spi_device *spi)
	130	{
a0c7c1d4 MR	131	struct mc13xxx *mc13xxx;
	132	struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
	133	int ret;
	134
e7c706b1	135	mc13xxx = devm_kzalloc(&spi->dev, sizeof(*mc13xxx), GFP_KERNEL);
a0c7c1d4 MR	136	if (!mc13xxx)
	137	return -ENOMEM;
	138
a720c305	139	spi_set_drvdata(spi, mc13xxx);
a0c7c1d4	140	spi->mode = SPI_MODE_0 \| SPI_CS_HIGH;
a0c7c1d4 MR	141
	142	mc13xxx->dev = &spi->dev;
	143	mutex_init(&mc13xxx->lock);
	144
e0308897 AL	145	mc13xxx->regmap = devm_regmap_init(&spi->dev, &regmap_mc13xxx_bus,
	146	&spi->dev,
	147	&mc13xxx_regmap_spi_config);
a0c7c1d4 MR	148	if (IS_ERR(mc13xxx->regmap)) {
	149	ret = PTR_ERR(mc13xxx->regmap);
	150	dev_err(mc13xxx->dev, "Failed to initialize register map: %d\n",
	151	ret);
a0c7c1d4 MR	152	return ret;
	153	}
	154
cd0f34b0 UKK	155	if (spi->dev.of_node) {
	156	const struct of_device_id *of_id =
	157	of_match_device(mc13xxx_dt_ids, &spi->dev);
a0c7c1d4	158
cd0f34b0	159	mc13xxx->variant = of_id->data;
a0c7c1d4	160	} else {
cd0f34b0 UKK	161	const struct spi_device_id *id_entry = spi_get_device_id(spi);
	162
	163	mc13xxx->variant = (void *)id_entry->driver_data;
a0c7c1d4 MR	164	}
a0c7c1d4 MR	165
cd0f34b0	166	return mc13xxx_common_init(mc13xxx, pdata, spi->irq);
a0c7c1d4 MR	167	}
a0c7c1d4 MR	168
4740f73f	169	static int mc13xxx_spi_remove(struct spi_device *spi)
a0c7c1d4	170	{
a720c305	171	struct mc13xxx *mc13xxx = spi_get_drvdata(spi);
a0c7c1d4 MR	172
	173	mc13xxx_common_cleanup(mc13xxx);
	174
	175	return 0;
	176	}
	177
	178	static struct spi_driver mc13xxx_spi_driver = {
	179	.id_table = mc13xxx_device_id,
	180	.driver = {
	181	.name = "mc13xxx",
	182	.owner = THIS_MODULE,
	183	.of_match_table = mc13xxx_dt_ids,
	184	},
	185	.probe = mc13xxx_spi_probe,
84449216	186	.remove = mc13xxx_spi_remove,
a0c7c1d4 MR	187	};
	188
	189	static int __init mc13xxx_init(void)
	190	{
	191	return spi_register_driver(&mc13xxx_spi_driver);
	192	}
	193	subsys_initcall(mc13xxx_init);
	194
	195	static void __exit mc13xxx_exit(void)
	196	{
	197	spi_unregister_driver(&mc13xxx_spi_driver);
	198	}
	199	module_exit(mc13xxx_exit);
	200
	201	MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
	202	MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
	203	MODULE_LICENSE("GPL v2");