Hello, this series is based on the most recent media-master with the following patch applied on top: "media: i2c: rdamc21: Fix warning on u8 cast" The series contains multiple changes: - patches from [1-8] contain enhancements to the existing camera module drivers. The first 7 patches apply to RDACM20 the same style comments received on RDACM21. Nothing controversial should be there. A cosmetic fix for the max9286 driver follows. - patch [9/16] contains a fixup for the RDACM21 camera module that is required to avoid sporadic failures during the system initialization. - From patches [10/16] a rework of the GMSL camera initialization procedure starts with 3 patches that prepare for the most substantial change on the series. The current initialization procedure for a GMSL chip looks like MAX9282 RDACM2x - probe() - init() - mux initialize() - probe camera 1 - probe() - init max9271 - init image sensor/ISP - enable noise immunity ... - camera 1 bound - probe camera n - probe() - init max9271 - init image sensor/ISP - enable noise immunity - camera n bound - all camera have probed - Increase channel amplitude This implies that all the initial configuration of the camera modules which requires several I2C transactions to configure the image sensor and the embedded ISP are run without noise immunity enabled. On a test of 50 boot cycle the failure rate for the RDACM21 camera module is around ~20% which is considerably bad. This series implements a different mechanism that allows to run the initialization of the camera module with noise immunity enabled, by splitting the operations between the usual probe() method and the .init() subdev core operation [1] The new procedure looks like MAX9282 RDACM2x - probe() - init() - mux initialize() - probe camera 1 - probe() - init max9271 - enable noise immunity - camera 1 bound - increase channel amplitude - camera 1.init() - init image sensor/ISP - restore initial channel amplitude ... - probe camera n - probe() - init max9271 - enable noise immunity - camera n bound - increase channel amplitude - camera n.init() - init image sensor/ISP - all camera have probed This allows to run the image sensor/ISP initialization with noise immunity enabled, as that's the part that requires the most I2C writes, being the components programmed with register-value tables. The same boot tests shows a failure percentage of 13%, considerably lower than the current version. It also allows to increase the I2C bit rate to the default 339 Kbps for which the setup/hold time are calibrated. Bouns points: this helps isolating the MAX9271 initialization and will make it easier making the max9271 a self-contained driver as suggested by Mauro. [1] All good and glorious BUT: all of this relies on the usage of a subdev operation that is considered deprecated. Is it an hard limitation ? GMSL is kind of different beast compared to usual subdevices, so it might make sense to make an exception in this case ? Thanks j Jacopo Mondi (16): media: i2c: rdacm20: Enable noise immunity media: i2c: rdacm20: Embedded 'serializer' field media: i2c: rdacm20: Replace goto with a loop media: i2c: rdacm20: Report camera module name media: i2c: rdacm20: Check return values media: i2c: rdacm20: Re-work ov10635 reset media: i2c: rdacm2x: Fix wake up delay media: i2c: max9286: Adjust parameters indent media: i2c: rdacm21: Re-work OV10640 initialization media: i2c: max9286: Rename reverse_channel_mv media: i2c: max9286: Cache channel amplitude media: i2c: max9286: Define high channel amplitude media: i2c: rdacm2x: Implement .init() subdev op media: i2c: max9286: Initialize remotes when bound media: i2c: max9286: Rework comments in .bound() media: i2c: gmsl: Use 339Kbps I2C bit-rate drivers/media/i2c/max9286.c | 67 ++++++++++------ drivers/media/i2c/rdacm20.c | 153 +++++++++++++++++++----------------- drivers/media/i2c/rdacm21.c | 73 ++++++++++------- 3 files changed, 167 insertions(+), 126 deletions(-) -- 2.30.0
