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Release 4.14 drivers/mfd/mc13xxx-spi.c

Directory: drivers/mfd
/*
 * 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/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 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_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; }

Contributors

PersonTokensPropCommitsCommitProp
Philippe Rétornaz164100.00%1100.00%
Total164100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Philippe Rétornaz5565.48%150.00%
Mark Brown2934.52%150.00%
Total84100.00%2100.00%

/* * 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; 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); }

Contributors

PersonTokensPropCommitsCommitProp
Marc Reilly13258.93%111.11%
Uwe Kleine-König3716.52%222.22%
Alexander Shiyan3616.07%333.33%
Axel Lin188.04%222.22%
Philippe Rétornaz10.45%111.11%
Total224100.00%9100.00%


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

Contributors

PersonTokensPropCommitsCommitProp
Marc Reilly1470.00%133.33%
Alexander Shiyan525.00%133.33%
Uwe Kleine-König15.00%133.33%
Total20100.00%3100.00%

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); }

Contributors

PersonTokensPropCommitsCommitProp
Marc Reilly16100.00%1100.00%
Total16100.00%1100.00%

subsys_initcall(mc13xxx_init);
static void __exit mc13xxx_exit(void) { spi_unregister_driver(&mc13xxx_spi_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Marc Reilly15100.00%1100.00%
Total15100.00%1100.00%

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");

Overall Contributors

PersonTokensPropCommitsCommitProp
Marc Reilly39849.14%17.69%
Philippe Rétornaz24830.62%215.38%
Uwe Kleine-König759.26%323.08%
Alexander Shiyan415.06%323.08%
Mark Brown293.58%17.69%
Axel Lin182.22%215.38%
Krzysztof Kozlowski10.12%17.69%
Total810100.00%13100.00%
Directory: drivers/mfd
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