From 995a418a6ca33e466e5e1527663ae3d5eee18304 Mon Sep 17 00:00:00 2001 From: Wang Jun <1742789905@qq.com> Date: Thu, 12 Mar 2026 22:51:36 +0800 Subject: [PATCH] auxdisplay: lcd2s: add error handling for i2c transfers The lcd2s_print() and lcd2s_gotoxy() functions currently ignore the return value of lcd2s_i2c_master_send(), which can fail. This can lead to silent data loss or incorrect cursor positioning. Add proper error checking: if the number of bytes sent does not match the expected length, return -EIO; otherwise propagate any error code from the I2C transfer. Signed-off-by: Wang Jun <1742789905@qq.com> Signed-off-by: Andy Shevchenko --- drivers/auxdisplay/lcd2s.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/auxdisplay/lcd2s.c b/drivers/auxdisplay/lcd2s.c index defb0573e43c..c7a962728752 100644 --- a/drivers/auxdisplay/lcd2s.c +++ b/drivers/auxdisplay/lcd2s.c @@ -99,8 +99,13 @@ static int lcd2s_print(struct charlcd *lcd, int c) { struct lcd2s_data *lcd2s = lcd->drvdata; u8 buf[2] = { LCD2S_CMD_WRITE, c }; + int ret; - lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf)); + ret = lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf)); + if (ret < 0) + return ret; + if (ret != sizeof(buf)) + return -EIO; return 0; } @@ -108,9 +113,13 @@ static int lcd2s_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y) { struct lcd2s_data *lcd2s = lcd->drvdata; u8 buf[3] = { LCD2S_CMD_CUR_POS, y + 1, x + 1 }; + int ret; - lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf)); - + ret = lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf)); + if (ret < 0) + return ret; + if (ret != sizeof(buf)) + return -EIO; return 0; }