On Wed, Apr 23, 2025 at 10:00:22AM +0200, Frieder Schrempf wrote:
Am 23.04.25 um 09:08 schrieb Francesco Dolcini:
On Wed, Apr 23, 2025 at 08:50:54AM +0200, Frieder Schrempf wrote:
Am 22.04.25 um 14:46 schrieb Wojciech Dubowik:
Define vqmmc regulator-gpio for usdhc2 with vin-supply coming from LDO5.
Without this definition LDO5 will be powered down, disabling SD card after bootup. This has been introduced in commit f5aab0438ef1 ("regulator: pca9450: Fix enable register for LDO5").
Fixes: f5aab0438ef1 ("regulator: pca9450: Fix enable register for LDO5")
Cc: stable@vger.kernel.org Signed-off-by: Wojciech Dubowik Wojciech.Dubowik@mt.com
...
With this solution (that I proposed), the sdcard driver just use the GPIO to select the right voltage and that's it, simple, no un-needed i2c communication with the PMIC, and the DT clearly describe the way the HW is designed.
Yes, but your solution relies on the fact that the LDO5 registers actually have the correct values for 1v8 and 3v3 setup. The bootloader might have changed these values. I would prefer it if we could have a solution that puts the LDO5 in a defined state, that is independent from any external conditions.
I do not think this is a real concern, the PMIC is programmed during manufacturing, if the PMIC programming is not correct we have way more issues ...
Francesco