[people/ms/u-boot.git] / drivers / i2c / pca9564_i2c.c

/*
 * File:         drivers/i2c/pca9564.c
 * Based on:     drivers/i2c/s3c44b0_i2c.c
 * Author:
 *
 * Created:      2009-06-23
 * Description:  PCA9564 i2c bridge driver
 *
 * Modified:
 *               Copyright 2009 CJSC "NII STT", http://www.niistt.ru/
 *
 * Bugs:
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <i2c.h>
#include <pca9564.h>
#include <asm/io.h>

#define PCA_STA			(CONFIG_PCA9564_BASE + 0)
#define PCA_TO			(CONFIG_PCA9564_BASE + 0)
#define PCA_DAT			(CONFIG_PCA9564_BASE + (1 << 2))
#define PCA_ADR			(CONFIG_PCA9564_BASE + (2 << 2))
#define PCA_CON			(CONFIG_PCA9564_BASE + (3 << 2))

static unsigned char pca_read_reg(unsigned int reg)
{
	return readb((void *)reg);
}

static void pca_write_reg(unsigned int reg, unsigned char value)
{
	writeb(value, (void *)reg);
}

static int pca_wait_busy(void)
{
	unsigned int timeout = 10000;

	while (!(pca_read_reg(PCA_CON) & PCA_CON_SI) && --timeout)
		udelay(1);

	if (timeout == 0)
		debug("I2C timeout!\n");

	debug("CON = 0x%02x, STA = 0x%02x\n", pca_read_reg(PCA_CON),
	       pca_read_reg(PCA_STA));

	return timeout ? 0 : 1;
}

/*=====================================================================*/
/*                         Public Functions                            */
/*=====================================================================*/

/*-----------------------------------------------------------------------
 * Initialization
 */
void i2c_init(int speed, int slaveaddr)
{
	pca_write_reg(PCA_CON, PCA_CON_ENSIO | speed);
}

/*
 * Probe the given I2C chip address.  Returns 0 if a chip responded,
 * not 0 on failure.
 */

int i2c_probe(uchar chip)
{
	unsigned char res;

	pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);
	pca_wait_busy();

	pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);

	pca_write_reg(PCA_DAT, (chip << 1) | 1);
	res = pca_wait_busy();

	if ((res == 0) && (pca_read_reg(PCA_STA) == 0x48))
		res = 1;

	pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);

	return res;
}

/*
 * Read/Write interface:
 *   chip:    I2C chip address, range 0..127
 *   addr:    Memory (register) address within the chip
 *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
 *              memories, 0 for register type devices with only one
 *              register)
 *   buffer:  Where to read/write the data
 *   len:     How many bytes to read/write
 *
 *   Returns: 0 on success, not 0 on failure
 */
int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
	int i;

	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
	pca_wait_busy();

	pca_write_reg(PCA_CON, PCA_CON_ENSIO);

	pca_write_reg(PCA_DAT, (chip << 1));
	pca_wait_busy();
	pca_write_reg(PCA_CON, PCA_CON_ENSIO);

	if (alen > 0) {
		pca_write_reg(PCA_DAT, addr);
		pca_wait_busy();
		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
	}

	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);

	udelay(500);

	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
	pca_wait_busy();
	pca_write_reg(PCA_CON, PCA_CON_ENSIO);

	pca_write_reg(PCA_DAT, (chip << 1) | 1);
	pca_wait_busy();

	for (i = 0; i < len; ++i) {
		if (i == len - 1)
			pca_write_reg(PCA_CON, PCA_CON_ENSIO);
		else
			pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_AA);

		pca_wait_busy();
		buffer[i] = pca_read_reg(PCA_DAT);

	}

	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);

	return 0;
}

int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
	int i;

	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
	pca_wait_busy();
	pca_write_reg(PCA_CON, PCA_CON_ENSIO);

	pca_write_reg(PCA_DAT, chip << 1);
	pca_wait_busy();
	pca_write_reg(PCA_CON, PCA_CON_ENSIO);

	if (alen > 0) {
		pca_write_reg(PCA_DAT, addr);
		pca_wait_busy();
		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
	}

	for (i = 0; i < len; ++i) {
		pca_write_reg(PCA_DAT, buffer[i]);
		pca_wait_busy();
		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
	}

	pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);

	return 0;
}
Commit	Line	Data
08ea550e VY	1	/*
	2	* File: drivers/i2c/pca9564.c
	3	* Based on: drivers/i2c/s3c44b0_i2c.c
	4	* Author:
	5	*
	6	* Created: 2009-06-23
	7	* Description: PCA9564 i2c bridge driver
	8	*
	9	* Modified:
	10	* Copyright 2009 CJSC "NII STT", http://www.niistt.ru/
	11	*
	12	* Bugs:
	13	*
1a459660	14	* SPDX-License-Identifier: GPL-2.0+
08ea550e VY	15	*/
	16
	17	#include <common.h>
	18	#include <i2c.h>
	19	#include <pca9564.h>
	20	#include <asm/io.h>
	21
	22	#define PCA_STA (CONFIG_PCA9564_BASE + 0)
	23	#define PCA_TO (CONFIG_PCA9564_BASE + 0)
	24	#define PCA_DAT (CONFIG_PCA9564_BASE + (1 << 2))
	25	#define PCA_ADR (CONFIG_PCA9564_BASE + (2 << 2))
	26	#define PCA_CON (CONFIG_PCA9564_BASE + (3 << 2))
	27
	28	static unsigned char pca_read_reg(unsigned int reg)
	29	{
	30	return readb((void *)reg);
	31	}
	32
	33	static void pca_write_reg(unsigned int reg, unsigned char value)
	34	{
	35	writeb(value, (void *)reg);
	36	}
	37
	38	static int pca_wait_busy(void)
	39	{
	40	unsigned int timeout = 10000;
	41
	42	while (!(pca_read_reg(PCA_CON) & PCA_CON_SI) && --timeout)
	43	udelay(1);
	44
	45	if (timeout == 0)
	46	debug("I2C timeout!\n");
	47
	48	debug("CON = 0x%02x, STA = 0x%02x\n", pca_read_reg(PCA_CON),
	49	pca_read_reg(PCA_STA));
	50
	51	return timeout ? 0 : 1;
	52	}
	53
	54	/=====================================================================/
	55	/* Public Functions */
	56	/=====================================================================/
	57
	58	/*-----------------------------------------------------------------------
	59	* Initialization
	60	*/
	61	void i2c_init(int speed, int slaveaddr)
	62	{
	63	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| speed);
	64	}
	65
	66	/*
	67	* Probe the given I2C chip address. Returns 0 if a chip responded,
	68	* not 0 on failure.
	69	*/
	70
	71	int i2c_probe(uchar chip)
	72	{
	73	unsigned char res;
	74
	75	pca_write_reg(PCA_CON, PCA_CON_STA \| PCA_CON_ENSIO);
	76	pca_wait_busy();
	77
	78	pca_write_reg(PCA_CON, PCA_CON_STA \| PCA_CON_ENSIO);
79
80	pca_write_reg(PCA_DAT, (chip << 1) \| 1);
81	res = pca_wait_busy();
82
83	if ((res == 0) && (pca_read_reg(PCA_STA) == 0x48))
84	res = 1;
85
86	pca_write_reg(PCA_CON, PCA_CON_STO \| PCA_CON_ENSIO);
87
88	return res;
89	}
90
91	/*
92	* Read/Write interface:
93	* chip: I2C chip address, range 0..127
94	* addr: Memory (register) address within the chip
95	* alen: Number of bytes to use for addr (typically 1, 2 for larger
96	* memories, 0 for register type devices with only one
97	* register)
98	* buffer: Where to read/write the data
99	* len: How many bytes to read/write
100	*
101	* Returns: 0 on success, not 0 on failure
102	*/
103	int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
104	{
105	int i;
106
107	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_STA);
108	pca_wait_busy();
109
110	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
111
112	pca_write_reg(PCA_DAT, (chip << 1));
113	pca_wait_busy();
114	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
115
116	if (alen > 0) {
117	pca_write_reg(PCA_DAT, addr);
118	pca_wait_busy();
119	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
120	}
121
122	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_STO);
123
124	udelay(500);
125
126	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_STA);
127	pca_wait_busy();
128	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
129
130	pca_write_reg(PCA_DAT, (chip << 1) \| 1);
131	pca_wait_busy();
132
133	for (i = 0; i < len; ++i) {
134	if (i == len - 1)
135	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
136	else
137	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_AA);
138
139	pca_wait_busy();
140	buffer[i] = pca_read_reg(PCA_DAT);
141
142	}
143
144	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_STO);
145
146	return 0;
147	}
148
149	int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
150	{
151	int i;
152
153	pca_write_reg(PCA_CON, PCA_CON_ENSIO \| PCA_CON_STA);
154	pca_wait_busy();
155	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
156
157	pca_write_reg(PCA_DAT, chip << 1);
158	pca_wait_busy();
159	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
160
161	if (alen > 0) {
162	pca_write_reg(PCA_DAT, addr);
163	pca_wait_busy();
164	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
165	}
166
167	for (i = 0; i < len; ++i) {
168	pca_write_reg(PCA_DAT, buffer[i]);
169	pca_wait_busy();
170	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
171	}
172
173	pca_write_reg(PCA_CON, PCA_CON_STO \| PCA_CON_ENSIO);
174
175	return 0;
176	}