From 3bc05faf37876f99e2a7baffa9c66fdcfb11d1f7 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 5 Dec 2023 17:42:30 +0100 Subject: net: dsa: microchip: properly support platform_data probing The ksz driver has bits and pieces of platform_data probing support, but it doesn't work. The conventional thing to do is to have an encapsulating structure for struct dsa_chip_data that gets put into dev->platform_data. This driver expects a struct ksz_platform_data, but that doesn't contain a struct dsa_chip_data as first element, which will obviously not work with dsa_switch_probe() -> dsa_switch_parse(). Pointing dev->platform_data to a struct dsa_chip_data directly is in principle possible, but that doesn't work either. The driver has ksz_switch_detect() to read the device ID from hardware, followed by ksz_check_device_id() to compare it against a predetermined expected value. This protects against early errors in the SPI/I2C communication. With platform_data, the mechanism in ksz_check_device_id() doesn't work and even leads to NULL pointer dereferences, since of_device_get_match_data() doesn't work in that probe path. So obviously, the platform_data support is actually missing, and the existing handling of struct ksz_platform_data is bogus. Complete the support by adding a struct dsa_chip_data as first element, and fixing up ksz_check_device_id() to pick up the platform_data instead of the unavailable of_device_get_match_data(). The early dev->chip_id assignment from ksz_switch_register() is also bogus, because ksz_switch_detect() sets it to an initial value. So remove it. Also, ksz_platform_data :: enabled_ports isn't used anywhere, delete it. Link: https://lore.kernel.org/netdev/20231204154315.3906267-1-dd@embedd.com/ Signed-off-by: Vladimir Oltean Signed-off-by: Daniel Danzberger Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- include/linux/platform_data/microchip-ksz.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux/platform_data') diff --git a/include/linux/platform_data/microchip-ksz.h b/include/linux/platform_data/microchip-ksz.h index ea1cc6d829e9..6480bf4af0fb 100644 --- a/include/linux/platform_data/microchip-ksz.h +++ b/include/linux/platform_data/microchip-ksz.h @@ -20,10 +20,12 @@ #define __MICROCHIP_KSZ_H #include +#include struct ksz_platform_data { + /* Must be first such that dsa_register_switch() can access it */ + struct dsa_chip_data cd; u32 chip_id; - u16 enabled_ports; }; #endif -- cgit v1.2.3