How to use spi device from another kernel module?
From: Joel Fernandes <hidden>
Date: 2016-12-07 05:12:24
On Tue, Dec 6, 2016 at 11:42 AM, Ran Shalit [off-list ref] wrote:
Hello, I have spi device which is registered using spi_register_board_info(), and I would like to get a pointer to this device in some other kernel module. Is there a simple way to get a pointer to pointer to a device , so that we can use it from other module ? (something like i2c_get_adapter for i2c)
Find out what's the SPI bus number (for the master) and the chip select on that SPI master (for the SPI device) Then you can use bus_for_each_device on spi_bus_type and find the spi_device you're looking for. See the following code for an example of how to use bus_for_each_device: http://lxr.free-electrons.com/source/drivers/spi/spi.c#L524 In your check function, just make sure your spi->master->bus_num is the bus you want and the spi->chip_select is the chip select corresponding to the device you want. If both these conditions are satisfied, there you have your spi_device. HTH, -Joel