[linux-2.6-block.git] / drivers / mfd / mc13xxx-spi.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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>
 */

#include <linux/slab.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/mfd/core.h>
#include <linux/mfd/mc13xxx.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 const 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_read = true,
	.use_single_write = true,
};

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 transfer.
 */

static const 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;
	int ret;

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

	dev_set_drvdata(&spi->dev, mc13xxx);

	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;

	mc13xxx->irq = spi->irq;

	spi->max_speed_hz = spi->max_speed_hz ? : 26000000;
	ret = spi_setup(spi);
	if (ret)
		return ret;

	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(&spi->dev, "Failed to initialize regmap: %d\n", ret);
		return ret;
	}

	mc13xxx->variant = spi_get_device_match_data(spi);

	return mc13xxx_common_init(&spi->dev);
}

static void mc13xxx_spi_remove(struct spi_device *spi)
{
	mc13xxx_common_exit(&spi->dev);
}

static struct spi_driver mc13xxx_spi_driver = {
	.id_table = mc13xxx_device_id,
	.driver = {
		.name = "mc13xxx",
		.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
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
a0c7c1d4 MR	2	/*
	3	* Copyright 2009-2010 Pengutronix
	4	* Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
	5	*
	6	* loosely based on an earlier driver that has
	7	* Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
a0c7c1d4 MR	8	*/
	9
	10	#include <linux/slab.h>
15d71e67	11	#include <linux/mod_devicetable.h>
a0c7c1d4 MR	12	#include <linux/module.h>
a0c7c1d4 MR	13	#include <linux/platform_device.h>
a0c7c1d4 MR	14	#include <linux/interrupt.h>
	15	#include <linux/mfd/core.h>
	16	#include <linux/mfd/mc13xxx.h>
a0c7c1d4 MR	17	#include <linux/err.h>
	18	#include <linux/spi/spi.h>
	19
	20	#include "mc13xxx.h"
	21
	22	static const struct spi_device_id mc13xxx_device_id[] = {
	23	{
	24	.name = "mc13783",
cd0f34b0	25	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13783,
a0c7c1d4 MR	26	}, {
a0c7c1d4 MR	27	.name = "mc13892",
cd0f34b0	28	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13892,
0312e024 UKK	29	}, {
	30	.name = "mc34708",
	31	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc34708,
a0c7c1d4 MR	32	}, {
	33	/* sentinel */
	34	}
	35	};
	36	MODULE_DEVICE_TABLE(spi, mc13xxx_device_id);
	37
	38	static const struct of_device_id mc13xxx_dt_ids[] = {
cd0f34b0 UKK	39	{ .compatible = "fsl,mc13783", .data = &mc13xxx_variant_mc13783, },
cd0f34b0 UKK	40	{ .compatible = "fsl,mc13892", .data = &mc13xxx_variant_mc13892, },
0312e024	41	{ .compatible = "fsl,mc34708", .data = &mc13xxx_variant_mc34708, },
a0c7c1d4 MR	42	{ /* sentinel */ }
	43	};
	44	MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);
	45
18dd21ab	46	static const struct regmap_config mc13xxx_regmap_spi_config = {
a0c7c1d4 MR	47	.reg_bits = 7,
	48	.pad_bits = 1,
	49	.val_bits = 24,
77a5b370	50	.write_flag_mask = 0x80,
a0c7c1d4 MR	51
	52	.max_register = MC13XXX_NUMREGS,
	53
	54	.cache_type = REGCACHE_NONE,
1c96a2f6 DF	55	.use_single_read = true,
1c96a2f6 DF	56	.use_single_write = true,
e4ecf6ea PR	57	};
	58
	59	static int mc13xxx_spi_read(void context, const void reg, size_t reg_size,
	60	void *val, size_t val_size)
	61	{
	62	unsigned char w[4] = { ((unsigned char ) reg), 0, 0, 0};
	63	unsigned char r[4];
	64	unsigned char *p = val;
	65	struct device *dev = context;
	66	struct spi_device *spi = to_spi_device(dev);
	67	struct spi_transfer t = {
	68	.tx_buf = w,
	69	.rx_buf = r,
	70	.len = 4,
	71	};
	72
	73	struct spi_message m;
	74	int ret;
	75
	76	if (val_size != 3 \|\| reg_size != 1)
	77	return -ENOTSUPP;
	78
	79	spi_message_init(&m);
	80	spi_message_add_tail(&t, &m);
	81	ret = spi_sync(spi, &m);
	82
	83	memcpy(p, &r[1], 3);
	84
	85	return ret;
	86	}
	87
	88	static int mc13xxx_spi_write(void context, const void data, size_t count)
	89	{
	90	struct device *dev = context;
	91	struct spi_device *spi = to_spi_device(dev);
fd792f8f	92	const char *reg = data;
e4ecf6ea PR	93
	94	if (count != 4)
	95	return -ENOTSUPP;
	96
fd792f8f MB	97	/* include errata fix for spi audio problems */
	98	if (reg == MC13783_AUDIO_CODEC \|\| reg == MC13783_AUDIO_DAC)
	99	spi_write(spi, data, count);
	100
e4ecf6ea PR	101	return spi_write(spi, data, count);
	102	}
	103
	104	/*
	105	* We cannot use regmap-spi generic bus implementation here.
	106	* The MC13783 chip will get corrupted if CS signal is deasserted
	107	* and on i.Mx31 SoC (the target SoC for MC13783 PMIC) the SPI controller
	108	* has the following errata (DSPhl22960):
	109	* "The CSPI negates SS when the FIFO becomes empty with
	110	* SSCTL= 0. Software cannot guarantee that the FIFO will not
	111	* drain because of higher priority interrupts and the
	112	* non-realtime characteristics of the operating system. As a
	113	* result, the SS will negate before all of the data has been
	114	* transferred to/from the peripheral."
	115	* We workaround this by accessing the SPI controller with a
0a5219f3	116	* single transfer.
e4ecf6ea PR	117	*/
e4ecf6ea PR	118
ef299323	119	static const struct regmap_bus regmap_mc13xxx_bus = {
e4ecf6ea PR	120	.write = mc13xxx_spi_write,
e4ecf6ea PR	121	.read = mc13xxx_spi_read,
a0c7c1d4 MR	122	};
	123
	124	static int mc13xxx_spi_probe(struct spi_device *spi)
	125	{
a0c7c1d4	126	struct mc13xxx *mc13xxx;
a0c7c1d4 MR	127	int ret;
a0c7c1d4 MR	128
e7c706b1	129	mc13xxx = devm_kzalloc(&spi->dev, sizeof(*mc13xxx), GFP_KERNEL);
a0c7c1d4 MR	130	if (!mc13xxx)
	131	return -ENOMEM;
	132
db9ef449 AS	133	dev_set_drvdata(&spi->dev, mc13xxx);
db9ef449 AS	134
a0c7c1d4	135	spi->mode = SPI_MODE_0 \| SPI_CS_HIGH;
a0c7c1d4	136
db9ef449	137	mc13xxx->irq = spi->irq;
a0c7c1d4	138
0cfe5c90	139	spi->max_speed_hz = spi->max_speed_hz ? : 26000000;
6a5926e6 AS	140	ret = spi_setup(spi);
	141	if (ret)
	142	return ret;
0cfe5c90	143
e0308897 AL	144	mc13xxx->regmap = devm_regmap_init(&spi->dev, &regmap_mc13xxx_bus,
	145	&spi->dev,
	146	&mc13xxx_regmap_spi_config);
a0c7c1d4 MR	147	if (IS_ERR(mc13xxx->regmap)) {
a0c7c1d4 MR	148	ret = PTR_ERR(mc13xxx->regmap);
db9ef449	149	dev_err(&spi->dev, "Failed to initialize regmap: %d\n", ret);
a0c7c1d4 MR	150	return ret;
	151	}
	152
15d71e67	153	mc13xxx->variant = spi_get_device_match_data(spi);
a0c7c1d4	154
db9ef449	155	return mc13xxx_common_init(&spi->dev);
a0c7c1d4 MR	156	}
a0c7c1d4 MR	157
a0386bba	158	static void mc13xxx_spi_remove(struct spi_device *spi)
a0c7c1d4	159	{
c39cf60f	160	mc13xxx_common_exit(&spi->dev);
a0c7c1d4 MR	161	}
	162
	163	static struct spi_driver mc13xxx_spi_driver = {
	164	.id_table = mc13xxx_device_id,
	165	.driver = {
	166	.name = "mc13xxx",
a0c7c1d4 MR	167	.of_match_table = mc13xxx_dt_ids,
	168	},
	169	.probe = mc13xxx_spi_probe,
84449216	170	.remove = mc13xxx_spi_remove,
a0c7c1d4 MR	171	};
	172
	173	static int __init mc13xxx_init(void)
	174	{
	175	return spi_register_driver(&mc13xxx_spi_driver);
	176	}
	177	subsys_initcall(mc13xxx_init);
	178
	179	static void __exit mc13xxx_exit(void)
	180	{
	181	spi_unregister_driver(&mc13xxx_spi_driver);
	182	}
	183	module_exit(mc13xxx_exit);
	184
	185	MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
	186	MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
	187	MODULE_LICENSE("GPL v2");