diff options
Diffstat (limited to 'drivers/s3c24x0_i2c.c')
-rw-r--r-- | drivers/s3c24x0_i2c.c | 196 |
1 files changed, 104 insertions, 92 deletions
diff --git a/drivers/s3c24x0_i2c.c b/drivers/s3c24x0_i2c.c index b501761..eeb6cf6 100644 --- a/drivers/s3c24x0_i2c.c +++ b/drivers/s3c24x0_i2c.c @@ -39,103 +39,114 @@ #ifdef CONFIG_HARD_I2C -#define IIC_WRITE 0 -#define IIC_READ 1 +#define I2C_WRITE 0 +#define I2C_READ 1 -#define IIC_OK 0 -#define IIC_NOK 1 -#define IIC_NACK 2 -#define IIC_NOK_LA 3 /* Lost arbitration */ -#define IIC_NOK_TOUT 4 /* time out */ +#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 IICSTAT_BSY 0x20 /* Busy bit */ -#define IICSTAT_NACK 0x01 /* Nack bit */ -#define IICCON_IRPND 0x10 /* Interrupt pending bit */ -#define IIC_MODE_MT 0xC0 /* Master Transmit Mode */ -#define IIC_MODE_MR 0x80 /* Master Receive Mode */ -#define IIC_START_STOP 0x20 /* START / STOP */ -#define IIC_TXRX_ENA 0x10 /* I2C Tx/Rx enable */ +#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 IIC_TIMEOUT 1 /* 1 seconde */ +#define I2C_TIMEOUT 1 /* 1 seconde */ -static int GetIICSDA(void) +static int GetI2CSDA(void) { - return (rGPEDAT & 0x8000) >> 15; + S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO(); + + return (gpio->GPEDAT & 0x8000) >> 15; } #if 0 -static void SetIICSDA(int x) +static void SetI2CSDA(int x) { rGPEDAT = (rGPEDAT & ~0x8000) | (x&1) << 15; } #endif -static void SetIICSCL(int x) +static void SetI2CSCL(int x) { - rGPEDAT = (rGPEDAT & ~0x4000) | (x&1) << 14; + S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO(); + + gpio->GPEDAT = (gpio->GPEDAT & ~0x4000) | (x&1) << 14; } static int WaitForXfer(void) { + S3C24X0_I2C * const i2c = S3C24X0_GetBase_I2C(); int i, status; - i = IIC_TIMEOUT * 1000; - status = rIICCON; - while ((i > 0) && !(status & IICCON_IRPND)) { + i = I2C_TIMEOUT * 1000; + status = i2c->IICCON; + while ((i > 0) && !(status & I2CCON_IRPND)) { udelay(1000); - status = rIICCON; + status = i2c->IICCON; i--; } - return(status & IICCON_IRPND) ? IIC_OK : IIC_NOK_TOUT; + return(status & I2CCON_IRPND) ? I2C_OK : I2C_NOK_TOUT; } static int IsACK(void) { - return(!(rIICSTAT & IICSTAT_NACK)); + S3C24X0_I2C * const i2c = S3C24X0_GetBase_I2C(); + + return(!(i2c->IICSTAT & I2CSTAT_NACK)); } static void ReadWriteByte(void) { - rIICCON &= ~IICCON_IRPND; + 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 = IIC_TIMEOUT * 1000; - status = rIICSTAT; - while ((i > 0) && (status & IICSTAT_BSY)) { + i = I2C_TIMEOUT * 1000; + status = i2c->IICSTAT; + while ((i > 0) && (status & I2CSTAT_BSY)) { udelay(1000); - status = rIICSTAT; + status = i2c->IICSTAT; i--; } - if ((status & IICSTAT_BSY) || GetIICSDA() == 0) { - ulong old_gpecon = rGPECON; + if ((status & I2CSTAT_BSY) || GetI2CSDA() == 0) { + ulong old_gpecon = gpio->GPECON; /* bus still busy probably by (most) previously interrupted transfer */ - /* set IICSDA and IICSCL (GPE15, GPE14) to GPIO */ - rGPECON = (rGPECON & ~0xF0000000) | 0x10000000; + /* set I2CSDA and I2CSCL (GPE15, GPE14) to GPIO */ + gpio->GPECON = (gpio->GPECON & ~0xF0000000) | 0x10000000; - /* toggle IICSCL until bus idle */ - SetIICSCL(0); udelay(1000); + /* toggle I2CSCL until bus idle */ + SetI2CSCL(0); udelay(1000); i = 10; - while ((i > 0) && (GetIICSDA() != 1)) { - SetIICSCL(1); udelay(1000); - SetIICSCL(0); udelay(1000); + while ((i > 0) && (GetI2CSDA() != 1)) { + SetI2CSCL(1); udelay(1000); + SetI2CSCL(0); udelay(1000); i--; } - SetIICSCL(1); udelay(1000); + SetI2CSCL(1); udelay(1000); /* restore pin functions */ - rGPECON = old_gpecon; + gpio->GPECON = old_gpecon; } /* calculate prescaler and divisor values */ @@ -150,13 +161,13 @@ void i2c_init (int speed, int slaveadd) /* set prescaler, divisor according to freq, also set ACKGEN, IRQ */ - rIICCON = (div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0); + i2c->IICCON = (div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0); /* init to SLAVE REVEIVE and set slaveaddr */ - rIICSTAT = 0; - rIICADD = slaveadd; + i2c->IICSTAT = 0; + i2c->IICADD = slaveadd; /* program Master Transmit (and implicit STOP) */ - rIICSTAT = IIC_MODE_MT | IIC_TXRX_ENA; + i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA; } @@ -176,142 +187,143 @@ int i2c_transfer(unsigned char cmd_type, 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 IIC_NOK; + return I2C_NOK; } //CheckDelay(); /* Check I2C bus idle */ - i = IIC_TIMEOUT * 1000; - status = rIICSTAT; - while ((i > 0) && (status & IICSTAT_BSY)) { + i = I2C_TIMEOUT * 1000; + status = i2c->IICSTAT; + while ((i > 0) && (status & I2CSTAT_BSY)) { udelay(1000); - status = rIICSTAT; + status = i2c->IICSTAT; i--; } - if (status & IICSTAT_BSY) { - result = IIC_NOK_TOUT; + if (status & I2CSTAT_BSY) { + result = I2C_NOK_TOUT; return(result); } - rIICCON |= 0x80; + i2c->IICCON |= 0x80; - result = IIC_OK; + result = I2C_OK; switch (cmd_type) { - case IIC_WRITE: + case I2C_WRITE: if (addr && addr_len) { - rIICDS = chip; + i2c->IICDS = chip; /* send START */ - rIICSTAT = IIC_MODE_MT | IIC_TXRX_ENA | IIC_START_STOP; + i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP; i = 0; - while ((i < addr_len) && (result == IIC_OK)) { + while ((i < addr_len) && (result == I2C_OK)) { result = WaitForXfer(); - rIICDS = addr[i]; + i2c->IICDS = addr[i]; ReadWriteByte(); i++; } i = 0; - while ((i < data_len) && (result == IIC_OK)) { + while ((i < data_len) && (result == I2C_OK)) { result = WaitForXfer(); - rIICDS = data[i]; + i2c->IICDS = data[i]; ReadWriteByte(); i++; } } else { - rIICDS = chip; + i2c->IICDS = chip; /* send START */ - rIICSTAT = IIC_MODE_MT | IIC_TXRX_ENA | IIC_START_STOP; + i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP; i = 0; - while ((i < data_len) && (result = IIC_OK)) { + while ((i < data_len) && (result = I2C_OK)) { result = WaitForXfer(); - rIICDS = data[i]; + i2c->IICDS = data[i]; ReadWriteByte(); i++; } } - if (result == IIC_OK) + if (result == I2C_OK) result = WaitForXfer(); /* send STOP */ - rIICSTAT = IIC_MODE_MR | IIC_TXRX_ENA; + i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; ReadWriteByte(); break; - case IIC_READ: + case I2C_READ: if (addr && addr_len) { - rIICSTAT = IIC_MODE_MT | IIC_TXRX_ENA; - rIICDS = chip; + i2c->IICSTAT = I2C_MODE_MT | I2C_TXRX_ENA; + i2c->IICDS = chip; /* send START */ - rIICSTAT |= IIC_START_STOP; + i2c->IICSTAT |= I2C_START_STOP; result = WaitForXfer(); if (IsACK()) { i = 0; - while ((i < addr_len) && (result == IIC_OK)) { - rIICDS = addr[i]; + while ((i < addr_len) && (result == I2C_OK)) { + i2c->IICDS = addr[i]; ReadWriteByte(); result = WaitForXfer(); i++; } - rIICDS = chip; + i2c->IICDS = chip; /* resend START */ - rIICSTAT = IIC_MODE_MR | IIC_TXRX_ENA | IIC_START_STOP; + i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP; ReadWriteByte(); result = WaitForXfer(); i = 0; - while ((i < data_len) && (result == IIC_OK)) { + while ((i < data_len) && (result == I2C_OK)) { /* disable ACK for final READ */ if (i == data_len - 1) - rIICCON &= ~0x80; + i2c->IICCON &= ~0x80; ReadWriteByte(); result = WaitForXfer(); - data[i] = rIICDS; + data[i] = i2c->IICDS; i++; } } else { - result = IIC_NACK; + result = I2C_NACK; } } else { - rIICSTAT = IIC_MODE_MR | IIC_TXRX_ENA; - rIICDS = chip; + i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; + i2c->IICDS = chip; /* send START */ - rIICSTAT |= IIC_START_STOP; + i2c->IICSTAT |= I2C_START_STOP; result = WaitForXfer(); if (IsACK()) { i = 0; - while ((i < data_len) && (result == IIC_OK)) { + while ((i < data_len) && (result == I2C_OK)) { /* disable ACK for final READ */ if (i == data_len - 1) - rIICCON &= ~0x80; + i2c->IICCON &= ~0x80; ReadWriteByte(); result = WaitForXfer(); - data[i] = rIICDS; + data[i] = i2c->IICDS; i++; } } else { - result = IIC_NACK; + result = I2C_NACK; } } /* send STOP */ - rIICSTAT = IIC_MODE_MR | IIC_TXRX_ENA; + i2c->IICSTAT = I2C_MODE_MR | I2C_TXRX_ENA; ReadWriteByte(); break; default: printf( "i2c_transfer: bad call\n" ); - result = IIC_NOK; + result = I2C_NOK; break; } @@ -329,7 +341,7 @@ int i2c_probe (uchar chip) * address was <ACK>ed (i.e. there was a chip at that address which * drove the data line low). */ - return(i2c_transfer (IIC_READ, chip << 1, 0, 0, buf, 1) != IIC_OK); + 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) @@ -365,7 +377,7 @@ int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len) if( alen > 0 ) chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); #endif - if( (ret = i2c_transfer(IIC_READ, chip<<1, &xaddr[4-alen], alen, buffer, len )) != 0) { + if( (ret = i2c_transfer(I2C_READ, chip<<1, &xaddr[4-alen], alen, buffer, len )) != 0) { printf( "I2c read: failed %d\n", ret); return 1; } @@ -403,7 +415,7 @@ int i2c_write (uchar chip, uint addr, int alen, uchar * buffer, int len) if( alen > 0 ) chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); #endif - return (i2c_transfer(IIC_WRITE, chip<<1, &xaddr[4-alen], alen, buffer, len ) != 0); + return (i2c_transfer(I2C_WRITE, chip<<1, &xaddr[4-alen], alen, buffer, len ) != 0); } #endif /* CONFIG_HARD_I2C */ |