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/*
* 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 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;
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;
mc13xxx->regmap = devm_regmap_init(&spi->dev, ®map_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 int mc13xxx_spi_remove(struct spi_device *spi)
{
return mc13xxx_common_exit(&spi->dev);
}
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");
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