Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Sudip Mukherjee | 535 | 83.46% | 1 | 5.00% |
Mike Rapoport | 73 | 11.39% | 12 | 60.00% |
Matthieu Simon | 21 | 3.28% | 1 | 5.00% |
Eric S. Stone | 3 | 0.47% | 1 | 5.00% |
Lorenzo Stoakes | 3 | 0.47% | 1 | 5.00% |
Matej Vasek | 2 | 0.31% | 1 | 5.00% |
Arnd Bergmann | 2 | 0.31% | 1 | 5.00% |
Greg Kroah-Hartman | 1 | 0.16% | 1 | 5.00% |
Elise Lennion | 1 | 0.16% | 1 | 5.00% |
Total | 641 | 20 |
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// SPDX-License-Identifier: GPL-2.0 #define USE_HW_I2C #ifdef USE_HW_I2C #include "ddk750_chip.h" #include "ddk750_reg.h" #include "ddk750_hwi2c.h" #include "ddk750_power.h" #define MAX_HWI2C_FIFO 16 #define HWI2C_WAIT_TIMEOUT 0xF0000 int sm750_hw_i2c_init(unsigned char bus_speed_mode) { unsigned int value; /* Enable GPIO 30 & 31 as IIC clock & data */ value = peek32(GPIO_MUX); value |= (GPIO_MUX_30 | GPIO_MUX_31); poke32(GPIO_MUX, value); /* * Enable Hardware I2C power. * TODO: Check if we need to enable GPIO power? */ sm750_enable_i2c(1); /* Enable the I2C Controller and set the bus speed mode */ value = peek32(I2C_CTRL) & ~(I2C_CTRL_MODE | I2C_CTRL_EN); if (bus_speed_mode) value |= I2C_CTRL_MODE; value |= I2C_CTRL_EN; poke32(I2C_CTRL, value); return 0; } void sm750_hw_i2c_close(void) { unsigned int value; /* Disable I2C controller */ value = peek32(I2C_CTRL) & ~I2C_CTRL_EN; poke32(I2C_CTRL, value); /* Disable I2C Power */ sm750_enable_i2c(0); /* Set GPIO 30 & 31 back as GPIO pins */ value = peek32(GPIO_MUX); value &= ~GPIO_MUX_30; value &= ~GPIO_MUX_31; poke32(GPIO_MUX, value); } static long hw_i2c_wait_tx_done(void) { unsigned int timeout; /* Wait until the transfer is completed. */ timeout = HWI2C_WAIT_TIMEOUT; while (!(peek32(I2C_STATUS) & I2C_STATUS_TX) && (timeout != 0)) timeout--; if (timeout == 0) return -1; return 0; } /* * This function writes data to the i2c slave device registers. * * Parameters: * addr - i2c Slave device address * length - Total number of bytes to be written to the device * 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 hw_i2c_write_data(unsigned char addr, unsigned int length, unsigned char *buf) { 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, peek32(I2C_CTRL) | I2C_CTRL_CTRL); /* Wait until the transfer is completed. */ if (hw_i2c_wait_tx_done() != 0) break; /* Subtract 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: * addr - i2c Slave device address * length - Total number of bytes to be 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 hw_i2c_read_data(unsigned char addr, unsigned int length, unsigned char *buf) { 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, peek32(I2C_CTRL) | I2C_CTRL_CTRL); /* 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); /* Subtract 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 * * Parameters: * deviceAddress - i2c Slave device address which register * to be read from * registerIndex - Slave device's register to be read * * Return Value: * Register value */ unsigned char sm750_hw_i2c_read_reg(unsigned char addr, unsigned char reg) { unsigned char value = 0xFF; if (hw_i2c_write_data(addr, 1, ®) == 1) hw_i2c_read_data(addr, 1, &value); return value; } /* * This function writes a value to the slave device's register * * Parameters: * deviceAddress - i2c Slave device address which register * to be written * registerIndex - Slave device's register to be written * data - Data to be written to the register * * Result: * 0 - Success * -1 - Fail */ int sm750_hw_i2c_write_reg(unsigned char addr, unsigned char reg, unsigned char data) { unsigned char value[2]; value[0] = reg; value[1] = data; if (hw_i2c_write_data(addr, 2, value) == 2) return 0; return -1; } #endif
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