Hello Wolfgang, Am Sonntag, 30. April 2023, 09:05:55 CEST schrieb Wolfram Sang: > * PGP Signed by an unknown key > > > > IIRC this is a general problem^w limitation of the clock framework, > > > clock providers cannot use clocks themselves in certain callback, e.g. > > > set_rate. > > > > Well, that's essentially impossible when this clock provider is attached > > via i2c. i2c transfers potentially need to change or prepare clocks. > > So, as I get it, this is not a specific lpi2c problem but affecting any > I2C controller driver which uses get_rate() to setup a transfer to a > remote I2C clock provider? And this lockdep warning is a false-positive? Yes, IMHO this could potentially occur on every I2C controller driver, if a clock provider while holding the clk_prepare_lock, e.g. during registration, issues an i2c transfer. I'm not so sure if this is a false-positive, but more like trying to do a nested lock. Best regards Alexander -- TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht München, HRB 105018 Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider http://www.tq-group.com/
