summaryrefslogtreecommitdiff
path: root/drivers/i2c
diff options
context:
space:
mode:
authorDmitry Osipenko <digetx@gmail.com>2020-09-30 01:18:52 +0300
committerWolfram Sang <wsa@kernel.org>2020-10-05 22:57:40 +0200
commit85934909678993827fe538d994d6e3da91f6e046 (patch)
tree48a776a2bd8d8a277660df7e5502b5fe76ecfc84 /drivers/i2c
parentd3dfd625ffb0632e2eb1edaf343df6c23bc6fd1e (diff)
i2c: tegra: Use reset_control_reset()
Use a single reset_control_reset() instead of assert/deasset couple in order to make code cleaner a tad. Note that the reset_control_reset() uses 1 microsecond delay instead of 2 that was used previously, but this shouldn't matter because one microsecond is a default reset time for most of Tegra peripherals and TRM doesn't mention anything special in regards to I2C controller's reset propagation time. In addition don't ignore potential error of the reset control by emitting a noisy warning if it fails, which will indicate an existence of a severe problem, while still allow machine to boot up. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c13
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index b813c0976c10..90ba2f5327c5 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -785,9 +785,16 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
u32 tsu_thd;
u8 tlow, thigh;
- reset_control_assert(i2c_dev->rst);
- udelay(2);
- reset_control_deassert(i2c_dev->rst);
+ /*
+ * The reset shouldn't ever fail in practice. The failure will be a
+ * sign of a severe problem that needs to be resolved. Still we don't
+ * want to fail the initialization completely because this may break
+ * kernel boot up since voltage regulators use I2C. Hence, we will
+ * emit a noisy warning on error, which won't stay unnoticed and
+ * won't hose machine entirely.
+ */
+ err = reset_control_reset(i2c_dev->rst);
+ WARN_ON_ONCE(err);
if (i2c_dev->is_dvc)
tegra_dvc_init(i2c_dev);