-How to port a serial driver to driver model
-===========================================
+.. SPDX-License-Identifier: GPL-2.0+
+
+How to port an I2C driver to driver model
+=========================================
Over half of the I2C drivers have been converted as at November 2016. These
ones remain:
- adi_i2c
- davinci_i2c
- fti2c010
- ihs_i2c
- kona_i2c
- lpc32xx_i2c
- pca9564_i2c
- ppc4xx_i2c
- rcar_i2c
- sh_i2c
- soft_i2c
- zynq_i2c
+ * adi_i2c
+ * davinci_i2c
+ * fti2c010
+ * ihs_i2c
+ * kona_i2c
+ * lpc32xx_i2c
+ * pca9564_i2c
+ * ppc4xx_i2c
+ * rcar_i2c
+ * sh_i2c
+ * soft_i2c
+ * zynq_i2c
The deadline for this work is the end of June 2017. If no one steps
forward to convert these, at some point there may come a patch to remove them!
- Define CONFIG_DM_I2C for your board, vendor or architecture
- If the board does not already use driver model, you need CONFIG_DM also
- Your board should then build, but will not work fully since there will be
- no I2C driver
+ no I2C driver
- Add the U_BOOT_DRIVER piece at the end (e.g. copy tegra_i2c.c for example)
- Add a private struct for the driver data - avoid using static variables
- Implement each of the driver methods, perhaps by calling your old methods
- You may need to adjust the function parameters so that the old and new
- implementations can share most of the existing code
+ implementations can share most of the existing code
- If you convert all existing users of the driver, remove the pre-driver-model
- code
+ code
In terms of patches a conversion series typically has these patches:
- clean up / prepare the driver for conversion