diff options
| author | Jonathan Brandmeyer <jbrandmeyer@chromium.org> | 2018-08-09 12:58:03 -0600 |
|---|---|---|
| committer | chrome-bot <chrome-bot@chromium.org> | 2018-08-16 13:14:49 -0700 |
| commit | 39ab7a039676ef3738171ed00dc3c7f61802e7b3 (patch) | |
| tree | a32fdd410d4d41f2092dbaf283c44b528d4b03c4 /chip | |
| parent | 94d06cd5f92e163fca391529509f85909ed65ac6 (diff) | |
| download | chrome-ec-39ab7a039676ef3738171ed00dc3c7f61802e7b3.tar.gz | |
i2c: Split i2c_xfer into locked/unlocked versions.
Rename i2c_xfer to i2c_xfer_unlocked. Audit all users of i2c_xfer to
see if they can use simple locking semantics or require their own
locking. Since locked accesses are only safe for I2C_XFER_SINGLE
transactions, remove the flags parameter from i2c_xfer. This also makes
the audit a bit easier.
Some remaining applications hold the bus locked across several
transactions that would otherwise be atomic, and a few others implement
complex I2C transactions in multiple commands.
Add a (nondeterministic) verification on the I2C port locking
correctness. This will catch all statically incorrect locking patterns,
although dynamically incorrect locking patterns may not be caught.
Related: Revise the i2c_port_active_count to be a bitmap of the active
ports instead of a count of the active ports. The EC's mutex does not
provide an is_locked() primitive, and we would prefer not to have one.
- board/glados: Custom locking for battery reset
- board/mchpevb1: Custom locking for battery reset
- board/oak: Custom locking for battery reset
- board/samus: Custom locking for lightbar reset
- board/sweetberry: simple locking
- board/servo_micro: Custom locking for funky i2c transfers
- capsense: simple locking
- host_command_master: multi-command transactions
- lb_common: manual locking to support samus power sequence
- smbus: multi-command transactions
- usb_i2c: simple locking
- driver/tcpm/fusb302: simple locking and multi-command transactions
- driver/tcpm/tcpi: Forward _unlocked and implicitly locked interface to
fusb302
- driver/touchpad_elan: simple locking
BUG=chromium:871851
BRANCH=none
TEST=buildall; very careful audit
TEST=grunt clamshell and Coral clamshell, test boot, battery charging,
PD communication, and TCPC port low-power mode.
Signed-off-by: Jonathan Brandmeyer <jbrandmeyer@chromium.org>
Change-Id: Ieabf22bcab42780bdb994fca3ced5d8c62519d56
Reviewed-on: https://chromium-review.googlesource.com/1169913
Commit-Ready: Jonathan Brandmeyer <jbrandmeyer@chromium.org>
Tested-by: Jonathan Brandmeyer <jbrandmeyer@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>
Diffstat (limited to 'chip')
| -rw-r--r-- | chip/stm32/usb_power.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/chip/stm32/usb_power.c b/chip/stm32/usb_power.c index cc4f723322..7e4206e83b 100644 --- a/chip/stm32/usb_power.c +++ b/chip/stm32/usb_power.c @@ -411,10 +411,7 @@ uint16_t ina2xx_readagain(uint8_t port, uint8_t addr) int res; uint16_t val; - i2c_lock(port, 1); - res = i2c_xfer(port, addr, NULL, 0, (uint8_t *)&val, sizeof(uint16_t), - I2C_XFER_SINGLE); - i2c_lock(port, 0); + res = i2c_xfer(port, addr, NULL, 0, (uint8_t *)&val, sizeof(uint16_t)); if (res) { CPRINTS("INA2XX I2C readagain failed p:%d a:%02x", |