From 05a92e03c37ad88df07107121c5350cacb8d028f Mon Sep 17 00:00:00 2001 From: Luiz Otavio O Souza Date: Mon, 9 Dec 2013 11:51:17 +0000 Subject: [PATCH] Activate the device before attempt to access any of its registers. Without this change we may end up with a panic (Fatal kernel mode data abort: 'External Non-Linefetch Abort (S)') as described in http://e2e.ti.com/support/arm/sitara_arm/f/791/t/276862.aspx. It is now possible to bring up I2C1 and I2C2 on BBB. Approved by: adrian (mentor) --- sys/arm/ti/ti_i2c.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/sys/arm/ti/ti_i2c.c b/sys/arm/ti/ti_i2c.c index 28bf3cadd04c..f23a8ea9b66a 100644 --- a/sys/arm/ti/ti_i2c.c +++ b/sys/arm/ti/ti_i2c.c @@ -1076,20 +1076,20 @@ ti_i2c_attach(device_t dev) goto out; } - /* XXXOMAP3: FIXME get proper revision here */ - /* First read the version number of the I2C module */ - sc->sc_rev = ti_i2c_read_2(sc, I2C_REG_REVNB_HI) & 0xff; - - device_printf(dev, "I2C revision %d.%d\n", sc->sc_rev >> 4, - sc->sc_rev & 0xf); - - /* Activate the H/W */ + /* First we _must_ activate the H/W */ err = ti_i2c_activate(dev); if (err) { device_printf(dev, "ti_i2c_activate failed\n"); goto out; } + /* XXXOMAP3: FIXME get proper revision here */ + /* Read the version number of the I2C module */ + sc->sc_rev = ti_i2c_read_2(sc, I2C_REG_REVNB_HI) & 0xff; + + device_printf(dev, "I2C revision %d.%d\n", sc->sc_rev >> 4, + sc->sc_rev & 0xf); + /* activate the interrupt */ err = bus_setup_intr(dev, sc->sc_irq_res, INTR_TYPE_MISC | INTR_MPSAFE, NULL, ti_i2c_intr, sc, &sc->sc_irq_h);