/*
 * L3 code
 *
 *  Copyright (C) 2008, Christian Pellegrin <chripell@evolware.org>
 *
 * 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.
 *
 *
 * based on:
 *
 * L3 bus algorithm module.
 *
 *  Copyright (C) 2001 Russell King, All Rights Reserved.
 *
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/gpio.h>

#include <sound/l3.h>

/*
 * Send one byte of data to the chip.  Data is latched into the chip on
 * the rising edge of the clock.
 */
static void sendbyte(struct l3_pins *adap, unsigned int byte)
{
	int i;

	for (i = 0; i < 8; i++) {
		adap->setclk(adap, 0);
		udelay(adap->data_hold);
		adap->setdat(adap, byte & 1);
		udelay(adap->data_setup);
		adap->setclk(adap, 1);
		udelay(adap->clock_high);
		byte >>= 1;
	}
}

/*
 * Send a set of bytes to the chip.  We need to pulse the MODE line
 * between each byte, but never at the start nor at the end of the
 * transfer.
 */
static void sendbytes(struct l3_pins *adap, const u8 *buf,
		      int len)
{
	int i;

	for (i = 0; i < len; i++) {
		if (i) {
			udelay(adap->mode_hold);
			adap->setmode(adap, 0);
			udelay(adap->mode);
		}
		adap->setmode(adap, 1);
		udelay(adap->mode_setup);
		sendbyte(adap, buf[i]);
	}
}

int l3_write(struct l3_pins *adap, u8 addr, u8 *data, int len)
{
	adap->setclk(adap, 1);
	adap->setdat(adap, 1);
	adap->setmode(adap, 1);
	udelay(adap->mode);

	adap->setmode(adap, 0);
	udelay(adap->mode_setup);
	sendbyte(adap, addr);
	udelay(adap->mode_hold);

	sendbytes(adap, data, len);

	adap->setclk(adap, 1);
	adap->setdat(adap, 1);
	adap->setmode(adap, 0);

	return len;
}
EXPORT_SYMBOL_GPL(l3_write);


static void l3_set_clk(struct l3_pins *adap, int val)
{
	gpio_set_value(adap->gpio_clk, val);
}

static void l3_set_data(struct l3_pins *adap, int val)
{
	gpio_set_value(adap->gpio_data, val);
}

static void l3_set_mode(struct l3_pins *adap, int val)
{
	gpio_set_value(adap->gpio_mode, val);
}

int l3_set_gpio_ops(struct device *dev, struct l3_pins *adap)
{
	int ret;

	if (!adap->use_gpios)
		return -EINVAL;

	ret = devm_gpio_request_one(dev, adap->gpio_data,
				GPIOF_OUT_INIT_LOW, "l3_data");
	if (ret < 0)
		return ret;
	adap->setdat = l3_set_data;

	ret = devm_gpio_request_one(dev, adap->gpio_clk,
				GPIOF_OUT_INIT_LOW, "l3_clk");
	if (ret < 0)
		return ret;
	adap->setclk = l3_set_clk;

	ret = devm_gpio_request_one(dev, adap->gpio_mode,
				GPIOF_OUT_INIT_LOW, "l3_mode");
	if (ret < 0)
		return ret;
	adap->setmode = l3_set_mode;

	return 0;
}
EXPORT_SYMBOL_GPL(l3_set_gpio_ops);

MODULE_DESCRIPTION("L3 bit-banging driver");
MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
MODULE_LICENSE("GPL");
 <a href='/cgit.cgi/linux/net-next.git/log/?h=nds-private-remove&amp;id=e9f7f17d53003ee46ccbaf057f7820bfb6e76b9d'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound?h=nds-private-remove&amp;id=e9f7f17d53003ee46ccbaf057f7820bfb6e76b9d'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c?h=nds-private-remove&amp;id=e9f7f17d53003ee46ccbaf057f7820bfb6e76b9d'>i2c</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c/tea6330t.c?h=nds-private-remove&amp;id=e9f7f17d53003ee46ccbaf057f7820bfb6e76b9d'>tea6330t.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c/tea6330t.c?h=nds-private-remove&amp;id=e9f7f17d53003ee46ccbaf057f7820bfb6e76b9d&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
<option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd'>Diffstat</a> (limited to 'sound/soc/tegra')</div><table summary='diffstat' class='diffstat'>