From 86c64d41517c6a62acab553e35b8c9fe1575b405 Mon Sep 17 00:00:00 2001 From: Amaury Pouly Date: Sun, 3 Jul 2011 15:22:09 +0000 Subject: imx233: add missing i2c file git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30121 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/imx233/i2c-imx233.c | 186 ++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 firmware/target/arm/imx233/i2c-imx233.c (limited to 'firmware/target/arm/imx233/i2c-imx233.c') diff --git a/firmware/target/arm/imx233/i2c-imx233.c b/firmware/target/arm/imx233/i2c-imx233.c new file mode 100644 index 0000000000..9d29605bce --- /dev/null +++ b/firmware/target/arm/imx233/i2c-imx233.c @@ -0,0 +1,186 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2011 by amaury Pouly + * + * Based on Rockbox iriver bootloader by Linus Nielsen Feltzing + * and the ipodlinux bootloader by Daniel Palffy and Bernard Leach + * + * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ****************************************************************************/ +#include "config.h" +#include "system.h" +#include "kernel.h" +#include "dma-imx233.h" +#include "i2c-imx233.h" +#include "pinctrl-imx233.h" + +/* Used for DMA */ +struct i2c_dma_command_t +{ + struct apb_dma_command_t dma; + /* PIO words */ + uint32_t ctrl0; +}; + +#define I2C_NR_STAGES 4 +/* Current transfer */ +static int i2c_nr_stages; +static struct i2c_dma_command_t i2c_stage[I2C_NR_STAGES]; +static struct mutex i2c_mutex; +static struct semaphore i2c_sema; + +void INT_I2C_DMA(void) +{ + /* reset dma channel on error */ + if(imx233_dma_is_channel_error_irq(APB_I2C)) + imx233_dma_reset_channel(APB_I2C); + /* clear irq flags */ + imx233_dma_clear_channel_interrupt(APB_I2C); + semaphore_release(&i2c_sema); +} + +void imx233_i2c_init(void) +{ + __REG_SET(HW_I2C_CTRL0) = __BLOCK_SFTRST | __BLOCK_CLKGATE; + /* setup pins (must be done when shutdown) */ + imx233_set_pin_function(0, 30, PINCTRL_FUNCTION_MAIN); + imx233_set_pin_function(0, 31, PINCTRL_FUNCTION_MAIN); + /* clear softreset */ + __REG_CLR(HW_I2C_CTRL0) = __BLOCK_SFTRST | __BLOCK_CLKGATE; + /* Errata: + * When RETAIN_CLOCK is set, the ninth clock pulse (ACK) is not generated. However, the SDA + * line is read at the proper timing interval. If RETAIN_CLOCK is cleared, the ninth clock pulse is + * generated. + * HW_I2C_CTRL1[ACK_MODE] has default value of 0. It should be set to 1 to enable the fix for + * this issue. + */ + __REG_SET(HW_I2C_CTRL1) = HW_I2C_CTRL1__ACK_MODE; + __REG_SET(HW_I2C_CTRL0) = __BLOCK_CLKGATE; + /* Fast-mode @ 400K */ + HW_I2C_TIMING0 = 0x000F0007; /* tHIGH=0.6us, read at 0.3us */ + HW_I2C_TIMING1 = 0x001F000F; /* tLOW=1.3us, write at 0.6us */ + HW_I2C_TIMING2 = 0x0015000D; + + mutex_init(&i2c_mutex); + semaphore_init(&i2c_sema, 1, 0); +} + +void imx233_i2c_begin(void) +{ + mutex_lock(&i2c_mutex); + /* wakeup */ + __REG_CLR(HW_I2C_CTRL0) = __BLOCK_CLKGATE; + i2c_nr_stages = 0; +} + +enum imx233_i2c_error_t imx233_i2c_add(bool start, bool transmit, void *buffer, unsigned size, bool stop) +{ + if(i2c_nr_stages == I2C_NR_STAGES) + return I2C_ERROR; + if(i2c_nr_stages > 0) + { + i2c_stage[i2c_nr_stages - 1].dma.next = &i2c_stage[i2c_nr_stages].dma; + i2c_stage[i2c_nr_stages - 1].dma.cmd |= HW_APB_CHx_CMD__CHAIN; + if(!start) + i2c_stage[i2c_nr_stages - 1].ctrl0 |= HW_I2C_CTRL0__RETAIN_CLOCK; + } + i2c_stage[i2c_nr_stages].dma.buffer = buffer; + i2c_stage[i2c_nr_stages].dma.next = NULL; + i2c_stage[i2c_nr_stages].dma.cmd = + (transmit ? HW_APB_CHx_CMD__COMMAND__READ : HW_APB_CHx_CMD__COMMAND__WRITE) | + HW_APB_CHx_CMD__WAIT4ENDCMD | + 1 << HW_APB_CHx_CMD__CMDWORDS_BP | + size << HW_APB_CHx_CMD__XFER_COUNT_BP; + /* assume that any read is final (send nak on last) */ + i2c_stage[i2c_nr_stages].ctrl0 = size | + (transmit ? HW_I2C_CTRL0__TRANSMIT : HW_I2C_CTRL0__SEND_NAK_ON_LAST) | + (start ? HW_I2C_CTRL0__PRE_SEND_START : 0) | + (stop ? HW_I2C_CTRL0__POST_SEND_STOP : 0) | + HW_I2C_CTRL0__MASTER_MODE; + i2c_nr_stages++; + return I2C_SUCCESS; +} + +enum imx233_i2c_error_t imx233_i2c_end(unsigned timeout) +{ + if(i2c_nr_stages == 0) + return I2C_ERROR; + i2c_stage[i2c_nr_stages - 1].dma.cmd |= HW_APB_CHx_CMD__SEMAPHORE | HW_APB_CHx_CMD__IRQONCMPLT; + + __REG_CLR(HW_I2C_CTRL1) = HW_I2C_CTRL1__ALL_IRQ; + imx233_enable_interrupt(INT_SRC_I2C_DMA, true); + imx233_dma_enable_channel_interrupt(APB_I2C, true); + imx233_dma_reset_channel(APB_I2C); + imx233_dma_start_command(APB_I2C, &i2c_stage[0].dma); + + enum imx233_i2c_error_t ret ; + if(semaphore_wait(&i2c_sema, timeout) == OBJ_WAIT_TIMEDOUT) + { + imx233_dma_reset_channel(APB_I2C); + ret = I2C_TIMEOUT; + } + else if(HW_I2C_CTRL1 & HW_I2C_CTRL1__MASTER_LOSS_IRQ) + ret = I2C_MASTER_LOSS; + else if(HW_I2C_CTRL1 & HW_I2C_CTRL1__NO_SLAVE_ACK_IRQ) + ret= I2C_NO_SLAVE_ACK; + else if(HW_I2C_CTRL1 & HW_I2C_CTRL1__EARLY_TERM_IRQ) + ret = I2C_SLAVE_NAK; + else + ret = I2C_SUCCESS; + /* sleep */ + __REG_SET(HW_I2C_CTRL0) = __BLOCK_CLKGATE; + mutex_unlock(&i2c_mutex); + return ret; +} + +int i2c_write(int device, const unsigned char* buf, int count) +{ + uint8_t addr = device; + imx233_i2c_begin(); + imx233_i2c_add(true, true, &addr, 1, false); /* start + addr */ + imx233_i2c_add(false, true, (void *)buf, count, true); /* data + stop */ + return imx233_i2c_end(TIMEOUT_BLOCK); +} + +int i2c_read(int device, unsigned char* buf, int count) +{ + uint8_t addr = device | 1; + imx233_i2c_begin(); + imx233_i2c_add(true, true, &addr, 1, false); /* start + addr */ + imx233_i2c_add(false, false, buf, count, true); /* data + stop */ + return imx233_i2c_end(TIMEOUT_BLOCK); +} + +int i2c_readmem(int device, int address, unsigned char* buf, int count) +{ + uint8_t start[2] = {device, address}; + uint8_t addr_rd = device | 1; + imx233_i2c_begin(); + imx233_i2c_add(true, true, start, 2, false); /* start + addr + addr */ + imx233_i2c_add(true, true, &addr_rd, 1, false); /* start + addr */ + imx233_i2c_add(false, false, buf, count, true); /* data + stop */ + return imx233_i2c_end(TIMEOUT_BLOCK); +} + +int i2c_writemem(int device, int address, const unsigned char* buf, int count) +{ + uint8_t start[2] = {device, address}; + imx233_i2c_begin(); + imx233_i2c_add(true, true, start, 2, false); /* start + addr + addr */ + imx233_i2c_add(false, true, (void *)buf, count, true); /* data + stop */ + return imx233_i2c_end(TIMEOUT_BLOCK); +} -- cgit v1.2.3