[GitHub/mt8127/android_kernel_alcatel_ttab.git] / sound / soc / codecs / l3.c

/*
 * 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 <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(0);
		udelay(adap->data_hold);
		adap->setdat(byte & 1);
		udelay(adap->data_setup);
		adap->setclk(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(0);
			udelay(adap->mode);
		}
		adap->setmode(1);
		udelay(adap->mode_setup);
		sendbyte(adap, buf[i]);
	}
}

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

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

	sendbytes(adap, data, len);

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

	return len;
}
EXPORT_SYMBOL_GPL(l3_write);

MODULE_DESCRIPTION("L3 bit-banging driver");
MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
MODULE_LICENSE("GPL");
Commit	Line	Data
1cad1de1 CP	1	/*
	2	* L3 code
	3	*
	4	* Copyright (C) 2008, Christian Pellegrin <chripell@evolware.org>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	*
	11	* based on:
	12	*
	13	* L3 bus algorithm module.
	14	*
	15	* Copyright (C) 2001 Russell King, All Rights Reserved.
	16	*
	17	*
	18	*/
	19
	20	#include <linux/module.h>
	21	#include <linux/kernel.h>
	22	#include <linux/delay.h>
	23
	24	#include <sound/l3.h>
	25
	26	/*
	27	* Send one byte of data to the chip. Data is latched into the chip on
	28	* the rising edge of the clock.
	29	*/
	30	static void sendbyte(struct l3_pins *adap, unsigned int byte)
	31	{
	32	int i;
	33
	34	for (i = 0; i < 8; i++) {
	35	adap->setclk(0);
	36	udelay(adap->data_hold);
	37	adap->setdat(byte & 1);
	38	udelay(adap->data_setup);
	39	adap->setclk(1);
	40	udelay(adap->clock_high);
	41	byte >>= 1;
	42	}
	43	}
	44
	45	/*
	46	* Send a set of bytes to the chip. We need to pulse the MODE line
	47	* between each byte, but never at the start nor at the end of the
	48	* transfer.
	49	*/
	50	static void sendbytes(struct l3_pins adap, const u8 buf,
	51	int len)
	52	{
	53	int i;
	54
	55	for (i = 0; i < len; i++) {
	56	if (i) {
	57	udelay(adap->mode_hold);
	58	adap->setmode(0);
	59	udelay(adap->mode);
	60	}
	61	adap->setmode(1);
	62	udelay(adap->mode_setup);
	63	sendbyte(adap, buf[i]);
	64	}
65	}
66
67	int l3_write(struct l3_pins adap, u8 addr, u8 data, int len)
68	{
69	adap->setclk(1);
70	adap->setdat(1);
71	adap->setmode(1);
72	udelay(adap->mode);
73
74	adap->setmode(0);
75	udelay(adap->mode_setup);
76	sendbyte(adap, addr);
77	udelay(adap->mode_hold);
78
79	sendbytes(adap, data, len);
80
81	adap->setclk(1);
82	adap->setdat(1);
83	adap->setmode(0);
84
85	return len;
86	}
87	EXPORT_SYMBOL_GPL(l3_write);
88
89	MODULE_DESCRIPTION("L3 bit-banging driver");
90	MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");
91	MODULE_LICENSE("GPL");