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https://github.com/brain-hackers/u-boot-brain
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![Vignesh R](/assets/img/avatar_default.png)
As I2C can be used before DRAM initialization for reading EEPROM, avoid using static variables stored in BSS, since BSS is in DRAM, which may not have been initialised yet. Explicitly mark "static global" variables as belonging to the .data section. Signed-off-by: Vignesh R <vigneshr@ti.com> Acked-by: Heiko Schocher<hs@denx.de> Reviewed-by: Simon Glass <sjg@chromium.org>
130 lines
2.4 KiB
C
130 lines
2.4 KiB
C
/*
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* Copyright (c) 2014 Google, Inc
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <dm.h>
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#include <errno.h>
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#include <i2c.h>
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static int cur_busnum __attribute__((section(".data")));
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static int i2c_compat_get_device(uint chip_addr, int alen,
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struct udevice **devp)
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{
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struct dm_i2c_chip *chip;
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int ret;
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ret = i2c_get_chip_for_busnum(cur_busnum, chip_addr, alen, devp);
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if (ret)
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return ret;
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chip = dev_get_parent_platdata(*devp);
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if (chip->offset_len != alen) {
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printf("I2C chip %x: requested alen %d does not match chip offset_len %d\n",
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chip_addr, alen, chip->offset_len);
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return -EADDRNOTAVAIL;
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}
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return 0;
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}
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int i2c_probe(uint8_t chip_addr)
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{
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struct udevice *bus, *dev;
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int ret;
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ret = uclass_get_device_by_seq(UCLASS_I2C, cur_busnum, &bus);
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if (ret) {
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debug("Cannot find I2C bus %d: err=%d\n", cur_busnum, ret);
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return ret;
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}
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if (!bus)
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return -ENOENT;
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return dm_i2c_probe(bus, chip_addr, 0, &dev);
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}
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int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
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int len)
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{
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struct udevice *dev;
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int ret;
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ret = i2c_compat_get_device(chip_addr, alen, &dev);
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if (ret)
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return ret;
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return dm_i2c_read(dev, addr, buffer, len);
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}
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int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
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int len)
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{
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struct udevice *dev;
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int ret;
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ret = i2c_compat_get_device(chip_addr, alen, &dev);
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if (ret)
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return ret;
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return dm_i2c_write(dev, addr, buffer, len);
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}
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int i2c_get_bus_num_fdt(int node)
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{
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struct udevice *bus;
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int ret;
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ret = uclass_get_device_by_of_offset(UCLASS_I2C, node, &bus);
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if (ret)
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return ret;
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return bus->seq;
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}
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unsigned int i2c_get_bus_num(void)
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{
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return cur_busnum;
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}
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int i2c_set_bus_num(unsigned int bus)
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{
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cur_busnum = bus;
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return 0;
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}
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void i2c_init(int speed, int slaveaddr)
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{
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/* Nothing to do here - the init happens through driver model */
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}
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void board_i2c_init(const void *blob)
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{
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/* Nothing to do here - the init happens through driver model */
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}
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uint8_t i2c_reg_read(uint8_t chip_addr, uint8_t offset)
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{
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struct udevice *dev;
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int ret;
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ret = i2c_compat_get_device(chip_addr, 1, &dev);
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if (ret)
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return 0xff;
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return dm_i2c_reg_read(dev, offset);
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}
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void i2c_reg_write(uint8_t chip_addr, uint8_t offset, uint8_t val)
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{
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struct udevice *dev;
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int ret;
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ret = i2c_compat_get_device(chip_addr, 1, &dev);
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if (!ret)
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dm_i2c_reg_write(dev, offset, val);
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}
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