From 07ac31f6f4cd558e53f6705dbe3033a7f0237eb8 Mon Sep 17 00:00:00 2001 From: Cory Maccarrone Date: Tue, 22 Dec 2009 18:06:13 -0700 Subject: [PATCH] i2c-omap: Don't write IE state in unidle if 0 Commit ef871432... (i2c-omap: OMAP3: PM: (re)init for every transfer to support off-mode) introduced a change which make the dev->iestate contents be written to the OMAP_I2C_IE_REG every time omap_i2c_unidle is called. Previously, the state was only written if it wasn't equal to zero. In omap_i2c_probe, omap_i2c_unidle() is called prior to omap_i2c_init(), in which case dev->iestate has not yet been initialized and will be set to zero. Having this value written to the registers causes deadlock while booting. As such, this change restores the original functionality. Signed-off-by: Cory Maccarrone Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-omap.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 75bf3ad18099..a64a192c44a4 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -247,7 +247,13 @@ static void omap_i2c_unidle(struct omap_i2c_dev *dev) omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); } dev->idle = 0; - omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); + + /* + * Don't write to this register if the IE state is 0 as it can + * cause deadlock. + */ + if (dev->iestate) + omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); } static void omap_i2c_idle(struct omap_i2c_dev *dev) -- GitLab