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| author | Valentin Yakovenkov <yakovenkov@niistt.ru> | 2009-10-26 18:49:06 -0400 | 
|---|---|---|
| committer | Heiko Schocher <hs@denx.de> | 2009-10-30 15:10:58 +0100 | 
| commit | 08ea550eef310e9d59d83f3cfd57a902373bf17f (patch) | |
| tree | 5e789d7ee570e4a12977d55a7a6133673d25d495 /drivers/i2c/pca9564_i2c.c | |
| parent | 08a1c6258c2a04cead33eac50d96ea89979dcb94 (diff) | |
| download | olio-uboot-2014.01-08ea550eef310e9d59d83f3cfd57a902373bf17f.tar.xz olio-uboot-2014.01-08ea550eef310e9d59d83f3cfd57a902373bf17f.zip | |
new PCA9564 i2c bridge driver
Signed-off-by: Valentin Yakovenkov <yakovenkov@niistt.ru>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'drivers/i2c/pca9564_i2c.c')
| -rw-r--r-- | drivers/i2c/pca9564_i2c.c | 189 | 
1 files changed, 189 insertions, 0 deletions
| diff --git a/drivers/i2c/pca9564_i2c.c b/drivers/i2c/pca9564_i2c.c new file mode 100644 index 000000000..199a9ee39 --- /dev/null +++ b/drivers/i2c/pca9564_i2c.c @@ -0,0 +1,189 @@ +/* + * 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: + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA + */ + +#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; +} |