From 5ed1c55fb4c23dc9f14b9c8d1d687f8c0ee703ac Mon Sep 17 00:00:00 2001 From: Michel Alex Date: Thu, 26 Oct 2023 05:47:41 +0000 Subject: [PATCH] misc: i2c_eeprom: consider pagesize when writing to eeprom Calculate the maximum length of the buffer when writing across the page boundary. If the buffer length (len) exceeds the page boundary (pagesize), split it. Use this length instead of comparing the length with the pagesize, because if the write start address (offset) is not at the beginning of a page and the page_offset + len is greater than the page boundary (pagesize), the write operation would overflow the current page and the behaviour can be undefined (e.g. at24). Signed-off-by: Alex Michel --- drivers/misc/i2c_eeprom.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/misc/i2c_eeprom.c b/drivers/misc/i2c_eeprom.c index e1d0b8f918..9111bd724c 100644 --- a/drivers/misc/i2c_eeprom.c +++ b/drivers/misc/i2c_eeprom.c @@ -60,6 +60,17 @@ static int i2c_eeprom_std_read(struct udevice *dev, int offset, uint8_t *buf, return dm_i2c_read(dev, offset, buf, size); } +static int i2c_eeprom_len(int offset, int len, int pagesize) +{ + int page_offset = offset & (pagesize - 1); + int maxlen = pagesize - page_offset; + + if (len > maxlen) + len = maxlen; + + return len; +} + static int i2c_eeprom_std_write(struct udevice *dev, int offset, const uint8_t *buf, int size) { @@ -67,7 +78,7 @@ static int i2c_eeprom_std_write(struct udevice *dev, int offset, int ret; while (size > 0) { - int write_size = min_t(int, size, priv->pagesize); + int write_size = i2c_eeprom_len(offset, size, priv->pagesize); ret = dm_i2c_write(dev, offset, buf, write_size); if (ret) -- 2.39.5