From 6217924a0127d073ac753c862a62c752320aa151 Mon Sep 17 00:00:00 2001 From: Daniel Danzberger Date: Tue, 5 Dec 2023 12:08:16 +0100 Subject: [PATCH] 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. --- drivers/net/dsa/microchip/ksz_common.c | 21 ++++++++++++-------- drivers/net/dsa/microchip/ksz_common.h | 19 +----------------- include/linux/platform_data/microchip-ksz.h | 22 ++++++++++++++++++++- 3 files changed, 35 insertions(+), 27 deletions(-) diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index dc9eea3c8..248dc034d 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -1457,15 +1457,23 @@ static const struct ksz_chip_data *ksz_lookup_info(unsigned int prod_num) static int ksz_check_device_id(struct ksz_device *dev) { - const struct ksz_chip_data *dt_chip_data; + const struct ksz_chip_data *expected_chip_data; + u32 expected_chip_id; - dt_chip_data = of_device_get_match_data(dev->dev); + if (dev->pdata) { + expected_chip_id = dev->pdata->chip_id; + expected_chip_data = ksz_lookup_info(expected_chip_id); + if (WARN_ON(!expected_chip_data)) + return -ENODEV; + } else { + expected_chip_data = of_device_get_match_data(dev->dev); + expected_chip_id = expected_chip_data->chip_id; + } - /* Check for Device Tree and Chip ID */ - if (dt_chip_data->chip_id != dev->chip_id) { + if (expected_chip_id != dev->chip_id) { dev_err(dev->dev, "Device tree specifies chip %s but found %s, please fix it!\n", - dt_chip_data->dev_name, dev->info->dev_name); + expected_chip_data->dev_name, dev->info->dev_name); return -ENODEV; } @@ -2900,9 +2908,6 @@ int ksz_switch_register(struct ksz_device *dev) int ret; int i; - if (dev->pdata) - dev->chip_id = dev->pdata->chip_id; - dev->reset_gpio = devm_gpiod_get_optional(dev->dev, "reset", GPIOD_OUT_LOW); if (IS_ERR(dev->reset_gpio)) diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h index d1b2db8e6..fe1525ffe 100644 --- a/drivers/net/dsa/microchip/ksz_common.h +++ b/drivers/net/dsa/microchip/ksz_common.h @@ -14,6 +14,7 @@ #include #include #include +#include #define KSZ_MAX_NUM_PORTS 8 @@ -162,24 +163,6 @@ enum ksz_model { LAN9374, }; -enum ksz_chip_id { - KSZ8563_CHIP_ID = 0x8563, - KSZ8795_CHIP_ID = 0x8795, - KSZ8794_CHIP_ID = 0x8794, - KSZ8765_CHIP_ID = 0x8765, - KSZ8830_CHIP_ID = 0x8830, - KSZ9477_CHIP_ID = 0x00947700, - KSZ9896_CHIP_ID = 0x00989600, - KSZ9897_CHIP_ID = 0x00989700, - KSZ9893_CHIP_ID = 0x00989300, - KSZ9567_CHIP_ID = 0x00956700, - LAN9370_CHIP_ID = 0x00937000, - LAN9371_CHIP_ID = 0x00937100, - LAN9372_CHIP_ID = 0x00937200, - LAN9373_CHIP_ID = 0x00937300, - LAN9374_CHIP_ID = 0x00937400, -}; - enum ksz_regs { REG_IND_CTRL_0, REG_IND_DATA_8, diff --git a/include/linux/platform_data/microchip-ksz.h b/include/linux/platform_data/microchip-ksz.h index ea1cc6d82..3f24a7a44 100644 --- a/include/linux/platform_data/microchip-ksz.h +++ b/include/linux/platform_data/microchip-ksz.h @@ -20,10 +20,30 @@ #define __MICROCHIP_KSZ_H #include +#include + +enum ksz_chip_id { + KSZ8563_CHIP_ID = 0x8563, + KSZ8795_CHIP_ID = 0x8795, + KSZ8794_CHIP_ID = 0x8794, + KSZ8765_CHIP_ID = 0x8765, + KSZ8830_CHIP_ID = 0x8830, + KSZ9477_CHIP_ID = 0x00947700, + KSZ9896_CHIP_ID = 0x00989600, + KSZ9897_CHIP_ID = 0x00989700, + KSZ9893_CHIP_ID = 0x00989300, + KSZ9567_CHIP_ID = 0x00956700, + LAN9370_CHIP_ID = 0x00937000, + LAN9371_CHIP_ID = 0x00937100, + LAN9372_CHIP_ID = 0x00937200, + LAN9373_CHIP_ID = 0x00937300, + LAN9374_CHIP_ID = 0x00937400, +}; 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 -- 2.39.2