Re: [PATCH] i2c: meson: Fix wrong speed use from probe

From: Neil Armstrong
Date: Mon Mar 07 2022 - 03:46:59 EST


On 01/03/2022 08:26, Lucas Tanure wrote:
Having meson_i2c_set_clk_div after i2c_add_adapter
causes issues for client drivers that try to use
the bus before the requested speed is applied.

The bus can be used just after i2c_add_adapter, so
move i2c_add_adapter to the final step as
meson_i2c_set_clk_div needs to be called before
the bus is used.

Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>
---
drivers/i2c/busses/i2c-meson.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c
index ef73a42577cc..07eb819072c4 100644
--- a/drivers/i2c/busses/i2c-meson.c
+++ b/drivers/i2c/busses/i2c-meson.c
@@ -465,18 +465,18 @@ static int meson_i2c_probe(struct platform_device *pdev)
*/
meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0);
- ret = i2c_add_adapter(&i2c->adap);
- if (ret < 0) {
- clk_disable_unprepare(i2c->clk);
- return ret;
- }
-
/* Disable filtering */
meson_i2c_set_mask(i2c, REG_SLAVE_ADDR,
REG_SLV_SDA_FILTER | REG_SLV_SCL_FILTER, 0);
meson_i2c_set_clk_div(i2c, timings.bus_freq_hz);
+ ret = i2c_add_adapter(&i2c->adap);
+ if (ret < 0) {
+ clk_disable_unprepare(i2c->clk);
+ return ret;
+ }
+
return 0;
}

Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>