This patch allows to read the REV_ID register in SPI mode and consequently to properly detect the max3109. Indeed in SPI mode, this register is only accessible by using indirect addressing. Signed-off-by: Gregory Hermant <gregory.hermant@xxxxxxxxxxxxxxxxx> --- drivers/tty/serial/max310x.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index 5183643..2d911f6 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -369,10 +369,13 @@ static int max3109_detect(struct device *dev) unsigned int val = 0; int ret; - ret = regmap_read(s->regmap, MAX310X_REVID_REG, &val); + ret = regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, + MAX310X_EXTREG_ENBL); if (ret) return ret; - + + regmap_read(s->regmap, MAX310X_REVID_EXTREG, &val); + regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, MAX310X_EXTREG_DSBL); if (((val & MAX310x_REV_MASK) != MAX3109_REV_ID)) { dev_err(dev, "%s ID 0x%02x does not match\n", s->devtype->name, val); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html