[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/module.h>
#include <linux/platform_device.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/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 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;
	}

	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(&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>
	11	#include <linux/module.h>
	12	#include <linux/platform_device.h>
a0c7c1d4 MR	13	#include <linux/interrupt.h>
	14	#include <linux/mfd/core.h>
	15	#include <linux/mfd/mc13xxx.h>
	16	#include <linux/of.h>
	17	#include <linux/of_device.h>
a0c7c1d4 MR	18	#include <linux/err.h>
	19	#include <linux/spi/spi.h>
	20
	21	#include "mc13xxx.h"
	22
	23	static const struct spi_device_id mc13xxx_device_id[] = {
	24	{
	25	.name = "mc13783",
cd0f34b0	26	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13783,
a0c7c1d4 MR	27	}, {
a0c7c1d4 MR	28	.name = "mc13892",
cd0f34b0	29	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13892,
0312e024 UKK	30	}, {
	31	.name = "mc34708",
	32	.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc34708,
a0c7c1d4 MR	33	}, {
	34	/* sentinel */
	35	}
	36	};
	37	MODULE_DEVICE_TABLE(spi, mc13xxx_device_id);
	38
	39	static const struct of_device_id mc13xxx_dt_ids[] = {
cd0f34b0 UKK	40	{ .compatible = "fsl,mc13783", .data = &mc13xxx_variant_mc13783, },
cd0f34b0 UKK	41	{ .compatible = "fsl,mc13892", .data = &mc13xxx_variant_mc13892, },
0312e024	42	{ .compatible = "fsl,mc34708", .data = &mc13xxx_variant_mc34708, },
a0c7c1d4 MR	43	{ /* sentinel */ }
	44	};
	45	MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);
	46
18dd21ab	47	static const struct regmap_config mc13xxx_regmap_spi_config = {
a0c7c1d4 MR	48	.reg_bits = 7,
	49	.pad_bits = 1,
	50	.val_bits = 24,
77a5b370	51	.write_flag_mask = 0x80,
a0c7c1d4 MR	52
	53	.max_register = MC13XXX_NUMREGS,
	54
	55	.cache_type = REGCACHE_NONE,
1c96a2f6 DF	56	.use_single_read = true,
1c96a2f6 DF	57	.use_single_write = true,
e4ecf6ea PR	58	};
	59
	60	static int mc13xxx_spi_read(void context, const void reg, size_t reg_size,
	61	void *val, size_t val_size)
	62	{
	63	unsigned char w[4] = { ((unsigned char ) reg), 0, 0, 0};
	64	unsigned char r[4];
	65	unsigned char *p = val;
	66	struct device *dev = context;
	67	struct spi_device *spi = to_spi_device(dev);
	68	struct spi_transfer t = {
	69	.tx_buf = w,
	70	.rx_buf = r,
	71	.len = 4,
	72	};
	73
	74	struct spi_message m;
	75	int ret;
	76
	77	if (val_size != 3 \|\| reg_size != 1)
	78	return -ENOTSUPP;
	79
	80	spi_message_init(&m);
	81	spi_message_add_tail(&t, &m);
	82	ret = spi_sync(spi, &m);
	83
	84	memcpy(p, &r[1], 3);
	85
	86	return ret;
	87	}
	88
	89	static int mc13xxx_spi_write(void context, const void data, size_t count)
	90	{
	91	struct device *dev = context;
	92	struct spi_device *spi = to_spi_device(dev);
fd792f8f	93	const char *reg = data;
e4ecf6ea PR	94
	95	if (count != 4)
	96	return -ENOTSUPP;
	97
fd792f8f MB	98	/* include errata fix for spi audio problems */
	99	if (reg == MC13783_AUDIO_CODEC \|\| reg == MC13783_AUDIO_DAC)
	100	spi_write(spi, data, count);
	101
e4ecf6ea PR	102	return spi_write(spi, data, count);
	103	}
	104
	105	/*
	106	* We cannot use regmap-spi generic bus implementation here.
	107	* The MC13783 chip will get corrupted if CS signal is deasserted
	108	* and on i.Mx31 SoC (the target SoC for MC13783 PMIC) the SPI controller
	109	* has the following errata (DSPhl22960):
	110	* "The CSPI negates SS when the FIFO becomes empty with
	111	* SSCTL= 0. Software cannot guarantee that the FIFO will not
	112	* drain because of higher priority interrupts and the
	113	* non-realtime characteristics of the operating system. As a
	114	* result, the SS will negate before all of the data has been
	115	* transferred to/from the peripheral."
	116	* We workaround this by accessing the SPI controller with a
0a5219f3	117	* single transfer.
e4ecf6ea PR	118	*/
	119
	120	static struct regmap_bus regmap_mc13xxx_bus = {
	121	.write = mc13xxx_spi_write,
	122	.read = mc13xxx_spi_read,
a0c7c1d4 MR	123	};
	124
	125	static int mc13xxx_spi_probe(struct spi_device *spi)
	126	{
a0c7c1d4	127	struct mc13xxx *mc13xxx;
a0c7c1d4 MR	128	int ret;
a0c7c1d4 MR	129
e7c706b1	130	mc13xxx = devm_kzalloc(&spi->dev, sizeof(*mc13xxx), GFP_KERNEL);
a0c7c1d4 MR	131	if (!mc13xxx)
	132	return -ENOMEM;
	133
db9ef449 AS	134	dev_set_drvdata(&spi->dev, mc13xxx);
db9ef449 AS	135
a0c7c1d4	136	spi->mode = SPI_MODE_0 \| SPI_CS_HIGH;
a0c7c1d4	137
db9ef449	138	mc13xxx->irq = spi->irq;
a0c7c1d4	139
0cfe5c90	140	spi->max_speed_hz = spi->max_speed_hz ? : 26000000;
6a5926e6 AS	141	ret = spi_setup(spi);
	142	if (ret)
	143	return ret;
0cfe5c90	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)) {
a0c7c1d4 MR	149	ret = PTR_ERR(mc13xxx->regmap);
db9ef449	150	dev_err(&spi->dev, "Failed to initialize regmap: %d\n", ret);
a0c7c1d4 MR	151	return ret;
	152	}
	153
cd0f34b0 UKK	154	if (spi->dev.of_node) {
	155	const struct of_device_id *of_id =
	156	of_match_device(mc13xxx_dt_ids, &spi->dev);
a0c7c1d4	157
cd0f34b0	158	mc13xxx->variant = of_id->data;
a0c7c1d4	159	} else {
cd0f34b0 UKK	160	const struct spi_device_id *id_entry = spi_get_device_id(spi);
	161
	162	mc13xxx->variant = (void *)id_entry->driver_data;
a0c7c1d4 MR	163	}
a0c7c1d4 MR	164
db9ef449	165	return mc13xxx_common_init(&spi->dev);
a0c7c1d4 MR	166	}
a0c7c1d4 MR	167
a0386bba	168	static void mc13xxx_spi_remove(struct spi_device *spi)
a0c7c1d4	169	{
c39cf60f	170	mc13xxx_common_exit(&spi->dev);
a0c7c1d4 MR	171	}
	172
	173	static struct spi_driver mc13xxx_spi_driver = {
	174	.id_table = mc13xxx_device_id,
	175	.driver = {
	176	.name = "mc13xxx",
a0c7c1d4 MR	177	.of_match_table = mc13xxx_dt_ids,
	178	},
	179	.probe = mc13xxx_spi_probe,
84449216	180	.remove = mc13xxx_spi_remove,
a0c7c1d4 MR	181	};
	182
	183	static int __init mc13xxx_init(void)
	184	{
	185	return spi_register_driver(&mc13xxx_spi_driver);
	186	}
	187	subsys_initcall(mc13xxx_init);
	188
	189	static void __exit mc13xxx_exit(void)
	190	{
	191	spi_unregister_driver(&mc13xxx_spi_driver);
	192	}
	193	module_exit(mc13xxx_exit);
	194
	195	MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
	196	MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
	197	MODULE_LICENSE("GPL v2");