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| author | Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> | 2009-03-30 18:58:40 +0200 | 
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| committer | Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> | 2009-03-30 18:58:40 +0200 | 
| commit | d3b635774194404bcd424f6b376419bce22076ad (patch) | |
| tree | be7c5057940c3e430cbd2852db5e520a9733b3e9 /drivers/i2c | |
| parent | 300f99f4539dd5caf7e19af5e4ea5eb259445913 (diff) | |
| download | olio-uboot-2014.01-d3b635774194404bcd424f6b376419bce22076ad.tar.xz olio-uboot-2014.01-d3b635774194404bcd424f6b376419bce22076ad.zip | |
s3c24x0: move i2c driver to drivers/i2c
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/Makefile | 1 | ||||
| -rw-r--r-- | drivers/i2c/s3c24x0_i2c.c | 442 | 
2 files changed, 443 insertions, 0 deletions
| diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 4b4d9db9e..ef32f1337 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -32,6 +32,7 @@ COBJS-$(CONFIG_I2C_MXC) += mxc_i2c.o  COBJS-$(CONFIG_DRIVER_OMAP1510_I2C) += omap1510_i2c.o  COBJS-$(CONFIG_DRIVER_OMAP24XX_I2C) += omap24xx_i2c.o  COBJS-$(CONFIG_DRIVER_OMAP34XX_I2C) += omap24xx_i2c.o +COBJS-$(CONFIG_DRIVER_S3C24X0_I2C) += s3c24x0_i2c.o  COBJS-$(CONFIG_S3C44B0_I2C) += s3c44b0_i2c.o  COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o  COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c new file mode 100644 index 000000000..f0c1aa340 --- /dev/null +++ b/drivers/i2c/s3c24x0_i2c.c @@ -0,0 +1,442 @@ +/* + * (C) Copyright 2002 + * David Mueller, ELSOFT AG, d.mueller@elsoft.ch + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +/* This code should work for both the S3C2400 and the S3C2410 + * as they seem to have the same I2C controller inside. + * The different address mapping is handled by the s3c24xx.h files below. + */ + +#include <common.h> +#if defined(CONFIG_S3C2400) +#include <s3c2400.h> +#elif defined(CONFIG_S3C2410) +#include <s3c2410.h> +#endif +#include <i2c.h> + +#ifdef CONFIG_HARD_I2C + +#define	I2C_WRITE	0 +#define I2C_READ	1 + +#define I2C_OK		0 +#define I2C_NOK		1 +#define I2C_NACK	2 +#define I2C_NOK_LA	3		/* Lost arbitration */ +#define I2C_NOK_TOUT	4		/* time out */ + +#define I2CSTAT_BSY	0x20		/* Busy bit */ +#define I2CSTAT_NACK	0x01		/* Nack bit */ +#define I2CCON_IRPND	0x10		/* Interrupt pending bit */ +#define I2C_MODE_MT	0xC0		/* Master Transmit Mode */ +#define I2C_MODE_MR	0x80		/* Master Receive Mode */ +#define I2C_START_STOP	0x20		/* START / STOP */ +#define I2C_TXRX_ENA	0x10		/* I2C Tx/Rx enable */ + +#define I2C_TIMEOUT 1			/* 1 second */ + + +static int GetI2CSDA(void) +{ +	S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO(); + +#ifdef CONFIG_S3C2410 +	return (gpio->GPEDAT & 0x8000) >> 15; +#endif +#ifdef CONFIG_S3C2400 +	return (gpio->PGDAT & 0x0020) >> 5; +#endif +} + +#if 0 +static void SetI2CSDA(int x) +{ +	rGPEDAT = (rGPEDAT & ~0x8000) | (x&1) << 15; +} +#endif + +static void SetI2CSCL(int x) +{ +	S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO(); + +#ifdef CONFIG_S3C2410 +	gpio->GPEDAT = (gpio->GPEDAT & ~0x4000) | (x&1) << 14; +#endif +#ifdef CONFIG_S3C2400 +	gpio->PGDAT = (gpio->PGDAT & ~0x0040) | (x&1) << 6; +#endif +} + + +static int WaitForXfer (void) +{ +	S3C24X0_I2C *const i2c = S3C24X0_GetBase_I2C (); +	int i, status; + +	i = I2C_TIMEOUT * 10000; +	status = i2c->IICCON; +	while ((i > 0) && !(status & I2CCON_IRPND)) { +		udelay (100); +		status = i2c->IICCON; +		i--; +	} + +	return (status & I2CCON_IRPND) ? I2C_OK : I2C_NOK_TOUT; +} + +static int IsACK (void) +{ +	S3C24X0_I2C *const i2c = S3C24X0_GetBase_I2C (); + +	return (!(i2c->IICSTAT & I2CSTAT_NACK)); +} + +static void ReadWriteByte (void) +{ +	S3C24X0_I2C *const i2c = S3C24X0_GetBase_I2C (); + +	i2c->IICCON &= ~I2CCON_IRPND; +} + +void i2c_init (int speed, int slaveadd) +{ +	S3C24X0_I2C *const i2c = S3C24X0_GetBase_I2C (); +	S3C24X0_GPIO *const gpio = S3C24X0_GetBase_GPIO (); +	ulong freq, pres = 16, div; +	int i, status; + +	/* wait for some time to give previous transfer a chance to finish */ + +	i = I2C_TIMEOUT * 1000; +	status = i2c->IICSTAT; +	while ((i > 0) && (status & I2CSTAT_BSY)) { +		udelay (1000); +		status = i2c->IICSTAT; +		i--; +	} + +	if ((status & I2CSTAT_BSY) || GetI2CSDA () == 0) { +#ifdef CONFIG_S3C2410 +		ulong old_gpecon = gpio->GPECON; +#endif +#ifdef CONFIG_S3C2400 +		ulong old_gpecon = gpio->PGCON; +#endif +		/* bus still busy probably by (most) previously interrupted transfer */ + +#ifdef CONFIG_S3C2410 +		/* set I2CSDA and I2CSCL (GPE15, GPE14) to GPIO */ +		gpio->GPECON = (gpio->GPECON & ~0xF0000000) | 0x10000000; +#endif +#ifdef CONFIG_S3C2400 +		/* set I2CSDA and I2CSCL (PG5, PG6) to GPIO */ +		gpio->PGCON = (gpio->PGCON & ~0x00003c00) | 0x00001000; +#endif + +		/* toggle I2CSCL until bus idle */ +		SetI2CSCL (0); +		udelay (1000); +		i = 10; +		while ((i > 0) && (GetI2CSDA () != 1)) { +			SetI2CSCL (1); +			udelay (1000); +			SetI2CSCL (0); +			udelay (1000); +			i--; +		} +		SetI2CSCL (1); +		udelay (1000); + +		/* restore pin functions */ +#ifdef CONFIG_S3C2410 +		gpio->GPECON = old_gpecon; +#endif +#ifdef CONFIG_S3C2400 +		gpio->PGCON = old_gpecon; +#endif +	} + +	/* calculate prescaler and divisor values */ +	freq = get_PCLK (); +	if ((freq / pres / (16 + 1)) > speed) +		/* set prescaler to 512 */ +		pres = 512; + +	div = 0; +	while ((freq / pres / (div + 1)) > speed) +		div++; + +	/* set prescaler, divisor according to freq, also set +	 * ACKGEN, IRQ */ +	i2c->IICCON = (div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0); + +	/* init to SLAVE REVEIVE and set slaveaddr */ +	i2c->IICSTAT = 0; +	i2c->IICADD = slaveadd; +	/* program Master Transmit (and implicit STOP) */ +	i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA; + +} + +/* + * cmd_type is 0 for write, 1 for read. + * + * addr_len can take any value from 0-255, it is only limited + * by the char, we could make it larger if needed. If it is + * 0 we skip the address write cycle. + */ +static +int i2c_transfer (unsigned char cmd_type, +		  unsigned char chip, +		  unsigned char addr[], +		  unsigned char addr_len, +		  unsigned char data[], unsigned short data_len) +{ +	S3C24X0_I2C *const i2c = S3C24X0_GetBase_I2C (); +	int i, status, result; + +	if (data == 0 || data_len == 0) { +		/*Don't support data transfer of no length or to address 0 */ +		printf ("i2c_transfer: bad call\n"); +		return I2C_NOK; +	} + +	/* Check I2C bus idle */ +	i = I2C_TIMEOUT * 1000; +	status = i2c->IICSTAT; +	while ((i > 0) && (status & I2CSTAT_BSY)) { +		udelay (1000); +		status = i2c->IICSTAT; +		i--; +	} + +	if (status & I2CSTAT_BSY) +		return I2C_NOK_TOUT; + +	i2c->IICCON |= 0x80; +	result = I2C_OK; + +	switch (cmd_type) { +	case I2C_WRITE: +		if (addr && addr_len) { +			i2c->IICDS = chip; +			/* send START */ +			i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP; +			i = 0; +			while ((i < addr_len) && (result == I2C_OK)) { +				result = WaitForXfer (); +				i2c->IICDS = addr[i]; +				ReadWriteByte (); +				i++; +			} +			i = 0; +			while ((i < data_len) && (result == I2C_OK)) { +				result = WaitForXfer (); +				i2c->IICDS = data[i]; +				ReadWriteByte (); +				i++; +			} +		} else { +			i2c->IICDS = chip; +			/* send START */ +			i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP; +			i = 0; +			while ((i < data_len) && (result = I2C_OK)) { +				result = WaitForXfer (); +				i2c->IICDS = data[i]; +				ReadWriteByte (); +				i++; +			} +		} + +		if (result == I2C_OK) +			result = WaitForXfer (); + +		/* send STOP */ +		i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; +		ReadWriteByte (); +		break; + +	case I2C_READ: +		if (addr && addr_len) { +			i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA; +			i2c->IICDS = chip; +			/* send START */ +			i2c->IICSTAT |= I2C_START_STOP; +			result = WaitForXfer (); +			if (IsACK ()) { +				i = 0; +				while ((i < addr_len) && (result == I2C_OK)) { +					i2c->IICDS = addr[i]; +					ReadWriteByte (); +					result = WaitForXfer (); +					i++; +				} + +				i2c->IICDS = chip; +				/* resend START */ +				i2c->IICSTAT =  I2C_MODE_MR | I2C_TXRX_ENA | +						I2C_START_STOP; +				ReadWriteByte (); +				result = WaitForXfer (); +				i = 0; +				while ((i < data_len) && (result == I2C_OK)) { +					/* disable ACK for final READ */ +					if (i == data_len - 1) +						i2c->IICCON &= ~0x80; +					ReadWriteByte (); +					result = WaitForXfer (); +					data[i] = i2c->IICDS; +					i++; +				} +			} else { +				result = I2C_NACK; +			} + +		} else { +			i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; +			i2c->IICDS = chip; +			/* send START */ +			i2c->IICSTAT |= I2C_START_STOP; +			result = WaitForXfer (); + +			if (IsACK ()) { +				i = 0; +				while ((i < data_len) && (result == I2C_OK)) { +					/* disable ACK for final READ */ +					if (i == data_len - 1) +						i2c->IICCON &= ~0x80; +					ReadWriteByte (); +					result = WaitForXfer (); +					data[i] = i2c->IICDS; +					i++; +				} +			} else { +				result = I2C_NACK; +			} +		} + +		/* send STOP */ +		i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; +		ReadWriteByte (); +		break; + +	default: +		printf ("i2c_transfer: bad call\n"); +		result = I2C_NOK; +		break; +	} + +	return (result); +} + +int i2c_probe (uchar chip) +{ +	uchar buf[1]; + +	buf[0] = 0; + +	/* +	 * What is needed is to send the chip address and verify that the +	 * address was <ACK>ed (i.e. there was a chip at that address which +	 * drove the data line low). +	 */ +	return (i2c_transfer (I2C_READ, chip << 1, 0, 0, buf, 1) != I2C_OK); +} + +int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len) +{ +	uchar xaddr[4]; +	int ret; + +	if (alen > 4) { +		printf ("I2C read: addr len %d not supported\n", alen); +		return 1; +	} + +	if (alen > 0) { +		xaddr[0] = (addr >> 24) & 0xFF; +		xaddr[1] = (addr >> 16) & 0xFF; +		xaddr[2] = (addr >> 8) & 0xFF; +		xaddr[3] = addr & 0xFF; +	} + +#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW +	/* +	 * EEPROM chips that implement "address overflow" are ones +	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of +	 * address and the extra bits end up in the "chip address" +	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like +	 * four 256 byte chips. +	 * +	 * Note that we consider the length of the address field to +	 * still be one byte because the extra address bits are +	 * hidden in the chip address. +	 */ +	if (alen > 0) +		chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); +#endif +	if ((ret = +	     i2c_transfer (I2C_READ, chip << 1, &xaddr[4 - alen], alen, +			   buffer, len)) != 0) { +		printf ("I2c read: failed %d\n", ret); +		return 1; +	} +	return 0; +} + +int i2c_write (uchar chip, uint addr, int alen, uchar * buffer, int len) +{ +	uchar xaddr[4]; + +	if (alen > 4) { +		printf ("I2C write: addr len %d not supported\n", alen); +		return 1; +	} + +	if (alen > 0) { +		xaddr[0] = (addr >> 24) & 0xFF; +		xaddr[1] = (addr >> 16) & 0xFF; +		xaddr[2] = (addr >> 8) & 0xFF; +		xaddr[3] = addr & 0xFF; +	} +#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW +	/* +	 * EEPROM chips that implement "address overflow" are ones +	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of +	 * address and the extra bits end up in the "chip address" +	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like +	 * four 256 byte chips. +	 * +	 * Note that we consider the length of the address field to +	 * still be one byte because the extra address bits are +	 * hidden in the chip address. +	 */ +	if (alen > 0) +		chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); +#endif +	return (i2c_transfer +		(I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, +		 len) != 0); +} +#endif	/* CONFIG_HARD_I2C */ |