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authorBill Richardson <wfrichar@chromium.org>2013-06-06 09:42:44 -0700
committerChromeBot <chrome-bot@google.com>2013-06-06 14:42:25 -0700
commit4ff299e29da884c055c23044e307c523fd198b60 (patch)
tree4ad93fe10cb57cec5267f1277843eee4d5d22215 /chip
parentd0d1564434ae991ac99a6ce54f6f3360f47017a8 (diff)
downloadchrome-ec-4ff299e29da884c055c23044e307c523fd198b60.tar.gz
Send STOP to clear bus when I2C encounters an error.
Reading from a nonexistant/nonresponsive smart battery fails (as it should). But then it leaves the i2c clock line low, so that subsequent i2cscan commands fail too. This change just sends a STOP to clear the bus when an i2c error occurs. BUG=chromium:247037 BRANCH=none TEST=none Change-Id: I599bed7149ed3dd3748f1a939c2ea8fdf65e3d72 Signed-off-by: Bill Richardson <wfrichar@chromium.org> Reviewed-on: https://gerrit.chromium.org/gerrit/57808 Reviewed-by: Randall Spangler <rspangler@chromium.org>
Diffstat (limited to 'chip')
-rw-r--r--chip/lm4/i2c.c9
1 files changed, 7 insertions, 2 deletions
diff --git a/chip/lm4/i2c.c b/chip/lm4/i2c.c
index 12b53c2aa8..6b43eb4a29 100644
--- a/chip/lm4/i2c.c
+++ b/chip/lm4/i2c.c
@@ -157,8 +157,10 @@ int i2c_xfer(int port, int slave_addr, const uint8_t *out, int out_size,
LM4_I2C_MCS(port) = reg_mcs;
rv = wait_idle(port);
- if (rv)
+ if (rv) {
+ LM4_I2C_MCS(port) = LM4_I2C_MCS_STOP;
return rv;
+ }
}
}
@@ -189,8 +191,10 @@ int i2c_xfer(int port, int slave_addr, const uint8_t *out, int out_size,
LM4_I2C_MCS(port) = reg_mcs;
rv = wait_idle(port);
- if (rv)
+ if (rv) {
+ LM4_I2C_MCS(port) = LM4_I2C_MCS_STOP;
return rv;
+ }
in[i] = LM4_I2C_MDR(port) & 0xff;
}
}
@@ -401,6 +405,7 @@ static int command_i2cread(int argc, char **argv)
LM4_I2C_MCS(port) = (i == count - 1 ? 0x05 : 0x09);
rv = wait_idle(port);
if (rv != EC_SUCCESS) {
+ LM4_I2C_MCS(port) = LM4_I2C_MCS_STOP;
i2c_lock(port, 0);
return rv;
}