diff options
Diffstat (limited to 'kernel/drivers/staging/sm750fb/ddk750_hwi2c.c')
| -rw-r--r-- | kernel/drivers/staging/sm750fb/ddk750_hwi2c.c | 333 |
1 files changed, 162 insertions, 171 deletions
diff --git a/kernel/drivers/staging/sm750fb/ddk750_hwi2c.c b/kernel/drivers/staging/sm750fb/ddk750_hwi2c.c index 7826376ed..7be211128 100644 --- a/kernel/drivers/staging/sm750fb/ddk750_hwi2c.c +++ b/kernel/drivers/staging/sm750fb/ddk750_hwi2c.c @@ -8,208 +8,204 @@ #define MAX_HWI2C_FIFO 16 #define HWI2C_WAIT_TIMEOUT 0xF0000 - -int hwI2CInit( - unsigned char busSpeedMode +int sm750_hw_i2c_init( +unsigned char bus_speed_mode ) { - unsigned int value; + unsigned int value; - /* Enable GPIO 30 & 31 as IIC clock & data */ + /* Enable GPIO 30 & 31 as IIC clock & data */ value = PEEK32(GPIO_MUX); - value = FIELD_SET(value, GPIO_MUX, 30, I2C) | - FIELD_SET(0, GPIO_MUX, 31, I2C); + value = FIELD_SET(value, GPIO_MUX, 30, I2C) | + FIELD_SET(0, GPIO_MUX, 31, I2C); POKE32(GPIO_MUX, value); - /* Enable Hardware I2C power. - TODO: Check if we need to enable GPIO power? - */ - enableI2C(1); - - /* Enable the I2C Controller and set the bus speed mode */ - value = PEEK32(I2C_CTRL); - if (busSpeedMode == 0) - value = FIELD_SET(value, I2C_CTRL, MODE, STANDARD); - else - value = FIELD_SET(value, I2C_CTRL, MODE, FAST); - value = FIELD_SET(value, I2C_CTRL, EN, ENABLE); - POKE32(I2C_CTRL, value); - - return 0; + /* Enable Hardware I2C power. + TODO: Check if we need to enable GPIO power? + */ + enableI2C(1); + + /* Enable the I2C Controller and set the bus speed mode */ + value = PEEK32(I2C_CTRL); + if (bus_speed_mode == 0) + value = FIELD_SET(value, I2C_CTRL, MODE, STANDARD); + else + value = FIELD_SET(value, I2C_CTRL, MODE, FAST); + value = FIELD_SET(value, I2C_CTRL, EN, ENABLE); + POKE32(I2C_CTRL, value); + + return 0; } - -void hwI2CClose(void) +void sm750_hw_i2c_close(void) { - unsigned int value; + unsigned int value; - /* Disable I2C controller */ - value = PEEK32(I2C_CTRL); - value = FIELD_SET(value, I2C_CTRL, EN, DISABLE); - POKE32(I2C_CTRL, value); + /* Disable I2C controller */ + value = PEEK32(I2C_CTRL); + value = FIELD_SET(value, I2C_CTRL, EN, DISABLE); + POKE32(I2C_CTRL, value); - /* Disable I2C Power */ - enableI2C(0); + /* Disable I2C Power */ + enableI2C(0); - /* Set GPIO 30 & 31 back as GPIO pins */ - value = PEEK32(GPIO_MUX); - value = FIELD_SET(value, GPIO_MUX, 30, GPIO); - value = FIELD_SET(value, GPIO_MUX, 31, GPIO); - POKE32(GPIO_MUX, value); + /* Set GPIO 30 & 31 back as GPIO pins */ + value = PEEK32(GPIO_MUX); + value = FIELD_SET(value, GPIO_MUX, 30, GPIO); + value = FIELD_SET(value, GPIO_MUX, 31, GPIO); + POKE32(GPIO_MUX, value); } - -static long hwI2CWaitTXDone(void) +static long hw_i2c_wait_tx_done(void) { - unsigned int timeout; + unsigned int timeout; - /* Wait until the transfer is completed. */ - timeout = HWI2C_WAIT_TIMEOUT; - while ((FIELD_GET(PEEK32(I2C_STATUS), I2C_STATUS, TX) != I2C_STATUS_TX_COMPLETED) && - (timeout != 0)) + /* Wait until the transfer is completed. */ + timeout = HWI2C_WAIT_TIMEOUT; + while ((FIELD_GET(PEEK32(I2C_STATUS), + I2C_STATUS, TX) != I2C_STATUS_TX_COMPLETED) && + (timeout != 0)) timeout--; if (timeout == 0) - return (-1); + return (-1); - return 0; + return 0; } - - /* * This function writes data to the i2c slave device registers. * * Parameters: - * deviceAddress - i2c Slave device address + * addr - i2c Slave device address * length - Total number of bytes to be written to the device - * pBuffer - The buffer that contains the data to be written to the + * buf - The buffer that contains the data to be written to the * i2c device. * * Return Value: * Total number of bytes those are actually written. */ -static unsigned int hwI2CWriteData( - unsigned char deviceAddress, - unsigned int length, - unsigned char *pBuffer +static unsigned int hw_i2c_write_data( + unsigned char addr, + unsigned int length, + unsigned char *buf ) { - unsigned char count, i; - unsigned int totalBytes = 0; - - /* Set the Device Address */ - POKE32(I2C_SLAVE_ADDRESS, deviceAddress & ~0x01); - - /* Write data. - * Note: - * Only 16 byte can be accessed per i2c start instruction. - */ - do - { - /* Reset I2C by writing 0 to I2C_RESET register to clear the previous status. */ - POKE32(I2C_RESET, 0); - - /* Set the number of bytes to be written */ - if (length < MAX_HWI2C_FIFO) - count = length - 1; - else - count = MAX_HWI2C_FIFO - 1; - POKE32(I2C_BYTE_COUNT, count); - - /* Move the data to the I2C data register */ - for (i = 0; i <= count; i++) - POKE32(I2C_DATA0 + i, *pBuffer++); - - /* Start the I2C */ - POKE32(I2C_CTRL, FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); - - /* Wait until the transfer is completed. */ - if (hwI2CWaitTXDone() != 0) - break; - - /* Substract length */ - length -= (count + 1); - - /* Total byte written */ - totalBytes += (count + 1); - - } while (length > 0); - - return totalBytes; + unsigned char count, i; + unsigned int total_bytes = 0; + + /* Set the Device Address */ + POKE32(I2C_SLAVE_ADDRESS, addr & ~0x01); + + /* Write data. + * Note: + * Only 16 byte can be accessed per i2c start instruction. + */ + do { + /* + * Reset I2C by writing 0 to I2C_RESET register to + * clear the previous status. + */ + POKE32(I2C_RESET, 0); + + /* Set the number of bytes to be written */ + if (length < MAX_HWI2C_FIFO) + count = length - 1; + else + count = MAX_HWI2C_FIFO - 1; + POKE32(I2C_BYTE_COUNT, count); + + /* Move the data to the I2C data register */ + for (i = 0; i <= count; i++) + POKE32(I2C_DATA0 + i, *buf++); + + /* Start the I2C */ + POKE32(I2C_CTRL, + FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); + + /* Wait until the transfer is completed. */ + if (hw_i2c_wait_tx_done() != 0) + break; + + /* Substract length */ + length -= (count + 1); + + /* Total byte written */ + total_bytes += (count + 1); + + } while (length > 0); + + return total_bytes; } - - - /* * This function reads data from the slave device and stores them * in the given buffer * * Parameters: - * deviceAddress - i2c Slave device address + * addr - i2c Slave device address * length - Total number of bytes to be read - * pBuffer - Pointer to a buffer to be filled with the data read + * buf - Pointer to a buffer to be filled with the data read * from the slave device. It has to be the same size as the * length to make sure that it can keep all the data read. * * Return Value: * Total number of actual bytes read from the slave device */ -static unsigned int hwI2CReadData( - unsigned char deviceAddress, - unsigned int length, - unsigned char *pBuffer +static unsigned int hw_i2c_read_data( + unsigned char addr, + unsigned int length, + unsigned char *buf ) { - unsigned char count, i; - unsigned int totalBytes = 0; - - /* Set the Device Address */ - POKE32(I2C_SLAVE_ADDRESS, deviceAddress | 0x01); - - /* Read data and save them to the buffer. - * Note: - * Only 16 byte can be accessed per i2c start instruction. - */ - do - { - /* Reset I2C by writing 0 to I2C_RESET register to clear all the status. */ - POKE32(I2C_RESET, 0); - - /* Set the number of bytes to be read */ - if (length <= MAX_HWI2C_FIFO) - count = length - 1; - else - count = MAX_HWI2C_FIFO - 1; - POKE32(I2C_BYTE_COUNT, count); - - /* Start the I2C */ - POKE32(I2C_CTRL, FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); - - /* Wait until transaction done. */ - if (hwI2CWaitTXDone() != 0) - break; - - /* Save the data to the given buffer */ - for (i = 0; i <= count; i++) - *pBuffer++ = PEEK32(I2C_DATA0 + i); - - /* Substract length by 16 */ - length -= (count + 1); - - /* Number of bytes read. */ - totalBytes += (count + 1); - - } while (length > 0); - - return totalBytes; + unsigned char count, i; + unsigned int total_bytes = 0; + + /* Set the Device Address */ + POKE32(I2C_SLAVE_ADDRESS, addr | 0x01); + + /* Read data and save them to the buffer. + * Note: + * Only 16 byte can be accessed per i2c start instruction. + */ + do { + /* + * Reset I2C by writing 0 to I2C_RESET register to + * clear all the status. + */ + POKE32(I2C_RESET, 0); + + /* Set the number of bytes to be read */ + if (length <= MAX_HWI2C_FIFO) + count = length - 1; + else + count = MAX_HWI2C_FIFO - 1; + POKE32(I2C_BYTE_COUNT, count); + + /* Start the I2C */ + POKE32(I2C_CTRL, + FIELD_SET(PEEK32(I2C_CTRL), I2C_CTRL, CTRL, START)); + + /* Wait until transaction done. */ + if (hw_i2c_wait_tx_done() != 0) + break; + + /* Save the data to the given buffer */ + for (i = 0; i <= count; i++) + *buf++ = PEEK32(I2C_DATA0 + i); + + /* Substract length by 16 */ + length -= (count + 1); + + /* Number of bytes read. */ + total_bytes += (count + 1); + + } while (length > 0); + + return total_bytes; } - - - /* * This function reads the slave device's register * @@ -221,23 +217,19 @@ static unsigned int hwI2CReadData( * Return Value: * Register value */ -unsigned char hwI2CReadReg( - unsigned char deviceAddress, - unsigned char registerIndex +unsigned char sm750_hw_i2c_read_reg( + unsigned char addr, + unsigned char reg ) { - unsigned char value = (0xFF); + unsigned char value = (0xFF); - if (hwI2CWriteData(deviceAddress, 1, ®isterIndex) == 1) - hwI2CReadData(deviceAddress, 1, &value); + if (hw_i2c_write_data(addr, 1, ®) == 1) + hw_i2c_read_data(addr, 1, &value); - return value; + return value; } - - - - /* * This function writes a value to the slave device's register * @@ -251,21 +243,20 @@ unsigned char hwI2CReadReg( * 0 - Success * -1 - Fail */ -int hwI2CWriteReg( - unsigned char deviceAddress, - unsigned char registerIndex, - unsigned char data +int sm750_hw_i2c_write_reg( + unsigned char addr, + unsigned char reg, + unsigned char data ) { - unsigned char value[2]; + unsigned char value[2]; - value[0] = registerIndex; - value[1] = data; - if (hwI2CWriteData(deviceAddress, 2, value) == 2) - return 0; + value[0] = reg; + value[1] = data; + if (hw_i2c_write_data(addr, 2, value) == 2) + return 0; - return (-1); + return (-1); } - #endif |