diff options
Diffstat (limited to 'qemu/roms/u-boot/drivers/i2c/mv_i2c.c')
-rw-r--r-- | qemu/roms/u-boot/drivers/i2c/mv_i2c.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/drivers/i2c/mv_i2c.c b/qemu/roms/u-boot/drivers/i2c/mv_i2c.c new file mode 100644 index 000000000..dac346334 --- /dev/null +++ b/qemu/roms/u-boot/drivers/i2c/mv_i2c.c @@ -0,0 +1,471 @@ +/* + * (C) Copyright 2000 + * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it + * + * (C) Copyright 2000 Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * + * (C) Copyright 2003 Pengutronix e.K. + * Robert Schwebel <r.schwebel@pengutronix.de> + * + * (C) Copyright 2011 Marvell Inc. + * Lei Wen <leiwen@marvell.com> + * + * SPDX-License-Identifier: GPL-2.0+ + * + * Back ported to the 8xx platform (from the 8260 platform) by + * Murray.Jensen@cmst.csiro.au, 27-Jan-01. + */ + +#include <common.h> +#include <asm/io.h> + +#ifdef CONFIG_HARD_I2C +#include <i2c.h> +#include "mv_i2c.h" + +#ifdef DEBUG_I2C +#define PRINTD(x) printf x +#else +#define PRINTD(x) +#endif + +/* All transfers are described by this data structure */ +struct i2c_msg { + u8 condition; + u8 acknack; + u8 direction; + u8 data; +}; + +struct mv_i2c { + u32 ibmr; + u32 pad0; + u32 idbr; + u32 pad1; + u32 icr; + u32 pad2; + u32 isr; + u32 pad3; + u32 isar; +}; + +static struct mv_i2c *base; +static void i2c_board_init(struct mv_i2c *base) +{ +#ifdef CONFIG_SYS_I2C_INIT_BOARD + u32 icr; + /* + * call board specific i2c bus reset routine before accessing the + * environment, which might be in a chip on that bus. For details + * about this problem see doc/I2C_Edge_Conditions. + * + * disable I2C controller first, otherwhise it thinks we want to + * talk to the slave port... + */ + icr = readl(&base->icr); + writel(readl(&base->icr) & ~(ICR_SCLE | ICR_IUE), &base->icr); + + i2c_init_board(); + + writel(icr, &base->icr); +#endif +} + +#ifdef CONFIG_I2C_MULTI_BUS +static u32 i2c_regs[CONFIG_MV_I2C_NUM] = CONFIG_MV_I2C_REG; +static unsigned int bus_initialized[CONFIG_MV_I2C_NUM]; +static unsigned int current_bus; + +int i2c_set_bus_num(unsigned int bus) +{ + if ((bus < 0) || (bus >= CONFIG_MV_I2C_NUM)) { + printf("Bad bus: %d\n", bus); + return -1; + } + + base = (struct mv_i2c *)i2c_regs[bus]; + current_bus = bus; + + if (!bus_initialized[current_bus]) { + i2c_board_init(base); + bus_initialized[current_bus] = 1; + } + + return 0; +} + +unsigned int i2c_get_bus_num(void) +{ + return current_bus; +} +#endif + +/* + * i2c_reset: - reset the host controller + * + */ +static void i2c_reset(void) +{ + writel(readl(&base->icr) & ~ICR_IUE, &base->icr); /* disable unit */ + writel(readl(&base->icr) | ICR_UR, &base->icr); /* reset the unit */ + udelay(100); + writel(readl(&base->icr) & ~ICR_IUE, &base->icr); /* disable unit */ + + i2c_clk_enable(); + + writel(CONFIG_SYS_I2C_SLAVE, &base->isar); /* set our slave address */ + writel(I2C_ICR_INIT, &base->icr); /* set control reg values */ + writel(I2C_ISR_INIT, &base->isr); /* set clear interrupt bits */ + writel(readl(&base->icr) | ICR_IUE, &base->icr); /* enable unit */ + udelay(100); +} + +/* + * i2c_isr_set_cleared: - wait until certain bits of the I2C status register + * are set and cleared + * + * @return: 1 in case of success, 0 means timeout (no match within 10 ms). + */ +static int i2c_isr_set_cleared(unsigned long set_mask, + unsigned long cleared_mask) +{ + int timeout = 1000, isr; + + do { + isr = readl(&base->isr); + udelay(10); + if (timeout-- < 0) + return 0; + } while (((isr & set_mask) != set_mask) + || ((isr & cleared_mask) != 0)); + + return 1; +} + +/* + * i2c_transfer: - Transfer one byte over the i2c bus + * + * This function can tranfer a byte over the i2c bus in both directions. + * It is used by the public API functions. + * + * @return: 0: transfer successful + * -1: message is empty + * -2: transmit timeout + * -3: ACK missing + * -4: receive timeout + * -5: illegal parameters + * -6: bus is busy and couldn't be aquired + */ +int i2c_transfer(struct i2c_msg *msg) +{ + int ret; + + if (!msg) + goto transfer_error_msg_empty; + + switch (msg->direction) { + case I2C_WRITE: + /* check if bus is not busy */ + if (!i2c_isr_set_cleared(0, ISR_IBB)) + goto transfer_error_bus_busy; + + /* start transmission */ + writel(readl(&base->icr) & ~ICR_START, &base->icr); + writel(readl(&base->icr) & ~ICR_STOP, &base->icr); + writel(msg->data, &base->idbr); + if (msg->condition == I2C_COND_START) + writel(readl(&base->icr) | ICR_START, &base->icr); + if (msg->condition == I2C_COND_STOP) + writel(readl(&base->icr) | ICR_STOP, &base->icr); + if (msg->acknack == I2C_ACKNAK_SENDNAK) + writel(readl(&base->icr) | ICR_ACKNAK, &base->icr); + if (msg->acknack == I2C_ACKNAK_SENDACK) + writel(readl(&base->icr) & ~ICR_ACKNAK, &base->icr); + writel(readl(&base->icr) & ~ICR_ALDIE, &base->icr); + writel(readl(&base->icr) | ICR_TB, &base->icr); + + /* transmit register empty? */ + if (!i2c_isr_set_cleared(ISR_ITE, 0)) + goto transfer_error_transmit_timeout; + + /* clear 'transmit empty' state */ + writel(readl(&base->isr) | ISR_ITE, &base->isr); + + /* wait for ACK from slave */ + if (msg->acknack == I2C_ACKNAK_WAITACK) + if (!i2c_isr_set_cleared(0, ISR_ACKNAK)) + goto transfer_error_ack_missing; + break; + + case I2C_READ: + + /* check if bus is not busy */ + if (!i2c_isr_set_cleared(0, ISR_IBB)) + goto transfer_error_bus_busy; + + /* start receive */ + writel(readl(&base->icr) & ~ICR_START, &base->icr); + writel(readl(&base->icr) & ~ICR_STOP, &base->icr); + if (msg->condition == I2C_COND_START) + writel(readl(&base->icr) | ICR_START, &base->icr); + if (msg->condition == I2C_COND_STOP) + writel(readl(&base->icr) | ICR_STOP, &base->icr); + if (msg->acknack == I2C_ACKNAK_SENDNAK) + writel(readl(&base->icr) | ICR_ACKNAK, &base->icr); + if (msg->acknack == I2C_ACKNAK_SENDACK) + writel(readl(&base->icr) & ~ICR_ACKNAK, &base->icr); + writel(readl(&base->icr) & ~ICR_ALDIE, &base->icr); + writel(readl(&base->icr) | ICR_TB, &base->icr); + + /* receive register full? */ + if (!i2c_isr_set_cleared(ISR_IRF, 0)) + goto transfer_error_receive_timeout; + + msg->data = readl(&base->idbr); + + /* clear 'receive empty' state */ + writel(readl(&base->isr) | ISR_IRF, &base->isr); + break; + default: + goto transfer_error_illegal_param; + } + + return 0; + +transfer_error_msg_empty: + PRINTD(("i2c_transfer: error: 'msg' is empty\n")); + ret = -1; goto i2c_transfer_finish; + +transfer_error_transmit_timeout: + PRINTD(("i2c_transfer: error: transmit timeout\n")); + ret = -2; goto i2c_transfer_finish; + +transfer_error_ack_missing: + PRINTD(("i2c_transfer: error: ACK missing\n")); + ret = -3; goto i2c_transfer_finish; + +transfer_error_receive_timeout: + PRINTD(("i2c_transfer: error: receive timeout\n")); + ret = -4; goto i2c_transfer_finish; + +transfer_error_illegal_param: + PRINTD(("i2c_transfer: error: illegal parameters\n")); + ret = -5; goto i2c_transfer_finish; + +transfer_error_bus_busy: + PRINTD(("i2c_transfer: error: bus is busy\n")); + ret = -6; goto i2c_transfer_finish; + +i2c_transfer_finish: + PRINTD(("i2c_transfer: ISR: 0x%04x\n", readl(&base->isr))); + i2c_reset(); + return ret; +} + +/* ------------------------------------------------------------------------ */ +/* API Functions */ +/* ------------------------------------------------------------------------ */ +void i2c_init(int speed, int slaveaddr) +{ +#ifdef CONFIG_I2C_MULTI_BUS + current_bus = 0; + base = (struct mv_i2c *)i2c_regs[current_bus]; +#else + base = (struct mv_i2c *)CONFIG_MV_I2C_REG; +#endif + + i2c_board_init(base); +} + +/* + * i2c_probe: - Test if a chip answers for a given i2c address + * + * @chip: address of the chip which is searched for + * @return: 0 if a chip was found, -1 otherwhise + */ +int i2c_probe(uchar chip) +{ + struct i2c_msg msg; + + i2c_reset(); + + msg.condition = I2C_COND_START; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = (chip << 1) + 1; + if (i2c_transfer(&msg)) + return -1; + + msg.condition = I2C_COND_STOP; + msg.acknack = I2C_ACKNAK_SENDNAK; + msg.direction = I2C_READ; + msg.data = 0x00; + if (i2c_transfer(&msg)) + return -1; + + return 0; +} + +/* + * i2c_read: - Read multiple bytes from an i2c device + * + * The higher level routines take into account that this function is only + * called with len < page length of the device (see configuration file) + * + * @chip: address of the chip which is to be read + * @addr: i2c data address within the chip + * @alen: length of the i2c data address (1..2 bytes) + * @buffer: where to write the data + * @len: how much byte do we want to read + * @return: 0 in case of success + */ +int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ + struct i2c_msg msg; + u8 addr_bytes[3]; /* lowest...highest byte of data address */ + + PRINTD(("i2c_read(chip=0x%02x, addr=0x%02x, alen=0x%02x, " + "len=0x%02x)\n", chip, addr, alen, len)); + + i2c_reset(); + + /* dummy chip address write */ + PRINTD(("i2c_read: dummy chip address write\n")); + msg.condition = I2C_COND_START; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = (chip << 1); + msg.data &= 0xFE; + if (i2c_transfer(&msg)) + return -1; + + /* + * send memory address bytes; + * alen defines how much bytes we have to send. + */ + /*addr &= ((1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)-1); */ + addr_bytes[0] = (u8)((addr >> 0) & 0x000000FF); + addr_bytes[1] = (u8)((addr >> 8) & 0x000000FF); + addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF); + + while (--alen >= 0) { + PRINTD(("i2c_read: send memory word address byte %1d\n", alen)); + msg.condition = I2C_COND_NORMAL; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = addr_bytes[alen]; + if (i2c_transfer(&msg)) + return -1; + } + + /* start read sequence */ + PRINTD(("i2c_read: start read sequence\n")); + msg.condition = I2C_COND_START; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = (chip << 1); + msg.data |= 0x01; + if (i2c_transfer(&msg)) + return -1; + + /* read bytes; send NACK at last byte */ + while (len--) { + if (len == 0) { + msg.condition = I2C_COND_STOP; + msg.acknack = I2C_ACKNAK_SENDNAK; + } else { + msg.condition = I2C_COND_NORMAL; + msg.acknack = I2C_ACKNAK_SENDACK; + } + + msg.direction = I2C_READ; + msg.data = 0x00; + if (i2c_transfer(&msg)) + return -1; + + *buffer = msg.data; + PRINTD(("i2c_read: reading byte (0x%08x)=0x%02x\n", + (unsigned int)buffer, *buffer)); + buffer++; + } + + i2c_reset(); + + return 0; +} + +/* + * i2c_write: - Write multiple bytes to an i2c device + * + * The higher level routines take into account that this function is only + * called with len < page length of the device (see configuration file) + * + * @chip: address of the chip which is to be written + * @addr: i2c data address within the chip + * @alen: length of the i2c data address (1..2 bytes) + * @buffer: where to find the data to be written + * @len: how much byte do we want to read + * @return: 0 in case of success + */ +int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ + struct i2c_msg msg; + u8 addr_bytes[3]; /* lowest...highest byte of data address */ + + PRINTD(("i2c_write(chip=0x%02x, addr=0x%02x, alen=0x%02x, " + "len=0x%02x)\n", chip, addr, alen, len)); + + i2c_reset(); + + /* chip address write */ + PRINTD(("i2c_write: chip address write\n")); + msg.condition = I2C_COND_START; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = (chip << 1); + msg.data &= 0xFE; + if (i2c_transfer(&msg)) + return -1; + + /* + * send memory address bytes; + * alen defines how much bytes we have to send. + */ + addr_bytes[0] = (u8)((addr >> 0) & 0x000000FF); + addr_bytes[1] = (u8)((addr >> 8) & 0x000000FF); + addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF); + + while (--alen >= 0) { + PRINTD(("i2c_write: send memory word address\n")); + msg.condition = I2C_COND_NORMAL; + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = addr_bytes[alen]; + if (i2c_transfer(&msg)) + return -1; + } + + /* write bytes; send NACK at last byte */ + while (len--) { + PRINTD(("i2c_write: writing byte (0x%08x)=0x%02x\n", + (unsigned int)buffer, *buffer)); + + if (len == 0) + msg.condition = I2C_COND_STOP; + else + msg.condition = I2C_COND_NORMAL; + + msg.acknack = I2C_ACKNAK_WAITACK; + msg.direction = I2C_WRITE; + msg.data = *(buffer++); + + if (i2c_transfer(&msg)) + return -1; + } + + i2c_reset(); + + return 0; +} +#endif /* CONFIG_HARD_I2C */ |