From b778c1b5debc4176baf93ed5085498e603f99343 Mon Sep 17 00:00:00 2001 From: Reinhard Pfau Date: Wed, 26 Jun 2013 15:55:14 +0200 Subject: [PATCH] i2c: fsl_i2c: i2c_read(): dont try to write address w/ alen=0 if alen is 0: no longer start a write cycle before reading data. Signed-off-by: Dirk Eibach Signed-off-by: Reinhard Pfau Acked-by: Heiko Schocher Signed-off-by: Andy Fleming --- drivers/i2c/fsl_i2c.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c index 1c7265d..5d7e010 100644 --- a/drivers/i2c/fsl_i2c.c +++ b/drivers/i2c/fsl_i2c.c @@ -383,13 +383,16 @@ i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) int i = -1; /* signal error */ u8 *a = (u8*)&addr; - if (i2c_wait4bus() >= 0 + if (i2c_wait4bus() < 0) + return -1; + + if ((!length || alen > 0) && i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0 && __i2c_write(&a[4 - alen], alen) == alen) i = 0; /* No error so far */ - if (length - && i2c_write_addr(dev, I2C_READ_BIT, 1) != 0) + if (length && + i2c_write_addr(dev, I2C_READ_BIT, alen ? 1 : 0) != 0) i = __i2c_read(data, length); writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr); -- 2.7.4