diff options
Diffstat (limited to 'drivers/net/dsa/realtek-smi-core.c')
-rw-r--r-- | drivers/net/dsa/realtek-smi-core.c | 523 |
1 files changed, 0 insertions, 523 deletions
diff --git a/drivers/net/dsa/realtek-smi-core.c b/drivers/net/dsa/realtek-smi-core.c deleted file mode 100644 index aae46ada8d83..000000000000 --- a/drivers/net/dsa/realtek-smi-core.c +++ /dev/null @@ -1,523 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* Realtek Simple Management Interface (SMI) driver - * It can be discussed how "simple" this interface is. - * - * The SMI protocol piggy-backs the MDIO MDC and MDIO signals levels - * but the protocol is not MDIO at all. Instead it is a Realtek - * pecularity that need to bit-bang the lines in a special way to - * communicate with the switch. - * - * ASICs we intend to support with this driver: - * - * RTL8366 - The original version, apparently - * RTL8369 - Similar enough to have the same datsheet as RTL8366 - * RTL8366RB - Probably reads out "RTL8366 revision B", has a quite - * different register layout from the other two - * RTL8366S - Is this "RTL8366 super"? - * RTL8367 - Has an OpenWRT driver as well - * RTL8368S - Seems to be an alternative name for RTL8366RB - * RTL8370 - Also uses SMI - * - * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> - * Copyright (C) 2010 Antti Seppälä <a.seppala@gmail.com> - * Copyright (C) 2010 Roman Yeryomin <roman@advem.lv> - * Copyright (C) 2011 Colin Leitner <colin.leitner@googlemail.com> - * Copyright (C) 2009-2010 Gabor Juhos <juhosg@openwrt.org> - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/device.h> -#include <linux/spinlock.h> -#include <linux/skbuff.h> -#include <linux/of.h> -#include <linux/of_device.h> -#include <linux/of_mdio.h> -#include <linux/delay.h> -#include <linux/gpio/consumer.h> -#include <linux/platform_device.h> -#include <linux/regmap.h> -#include <linux/bitops.h> -#include <linux/if_bridge.h> - -#include "realtek-smi-core.h" - -#define REALTEK_SMI_ACK_RETRY_COUNT 5 -#define REALTEK_SMI_HW_STOP_DELAY 25 /* msecs */ -#define REALTEK_SMI_HW_START_DELAY 100 /* msecs */ - -static inline void realtek_smi_clk_delay(struct realtek_smi *smi) -{ - ndelay(smi->clk_delay); -} - -static void realtek_smi_start(struct realtek_smi *smi) -{ - /* Set GPIO pins to output mode, with initial state: - * SCK = 0, SDA = 1 - */ - gpiod_direction_output(smi->mdc, 0); - gpiod_direction_output(smi->mdio, 1); - realtek_smi_clk_delay(smi); - - /* CLK 1: 0 -> 1, 1 -> 0 */ - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 0); - realtek_smi_clk_delay(smi); - - /* CLK 2: */ - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdio, 0); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 0); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdio, 1); -} - -static void realtek_smi_stop(struct realtek_smi *smi) -{ - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdio, 0); - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdio, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 0); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 1); - - /* Add a click */ - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 0); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 1); - - /* Set GPIO pins to input mode */ - gpiod_direction_input(smi->mdio); - gpiod_direction_input(smi->mdc); -} - -static void realtek_smi_write_bits(struct realtek_smi *smi, u32 data, u32 len) -{ - for (; len > 0; len--) { - realtek_smi_clk_delay(smi); - - /* Prepare data */ - gpiod_set_value(smi->mdio, !!(data & (1 << (len - 1)))); - realtek_smi_clk_delay(smi); - - /* Clocking */ - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - gpiod_set_value(smi->mdc, 0); - } -} - -static void realtek_smi_read_bits(struct realtek_smi *smi, u32 len, u32 *data) -{ - gpiod_direction_input(smi->mdio); - - for (*data = 0; len > 0; len--) { - u32 u; - - realtek_smi_clk_delay(smi); - - /* Clocking */ - gpiod_set_value(smi->mdc, 1); - realtek_smi_clk_delay(smi); - u = !!gpiod_get_value(smi->mdio); - gpiod_set_value(smi->mdc, 0); - - *data |= (u << (len - 1)); - } - - gpiod_direction_output(smi->mdio, 0); -} - -static int realtek_smi_wait_for_ack(struct realtek_smi *smi) -{ - int retry_cnt; - - retry_cnt = 0; - do { - u32 ack; - - realtek_smi_read_bits(smi, 1, &ack); - if (ack == 0) - break; - - if (++retry_cnt > REALTEK_SMI_ACK_RETRY_COUNT) { - dev_err(smi->dev, "ACK timeout\n"); - return -ETIMEDOUT; - } - } while (1); - - return 0; -} - -static int realtek_smi_write_byte(struct realtek_smi *smi, u8 data) -{ - realtek_smi_write_bits(smi, data, 8); - return realtek_smi_wait_for_ack(smi); -} - -static int realtek_smi_write_byte_noack(struct realtek_smi *smi, u8 data) -{ - realtek_smi_write_bits(smi, data, 8); - return 0; -} - -static int realtek_smi_read_byte0(struct realtek_smi *smi, u8 *data) -{ - u32 t; - - /* Read data */ - realtek_smi_read_bits(smi, 8, &t); - *data = (t & 0xff); - - /* Send an ACK */ - realtek_smi_write_bits(smi, 0x00, 1); - - return 0; -} - -static int realtek_smi_read_byte1(struct realtek_smi *smi, u8 *data) -{ - u32 t; - - /* Read data */ - realtek_smi_read_bits(smi, 8, &t); - *data = (t & 0xff); - - /* Send an ACK */ - realtek_smi_write_bits(smi, 0x01, 1); - - return 0; -} - -static int realtek_smi_read_reg(struct realtek_smi *smi, u32 addr, u32 *data) -{ - unsigned long flags; - u8 lo = 0; - u8 hi = 0; - int ret; - - spin_lock_irqsave(&smi->lock, flags); - - realtek_smi_start(smi); - - /* Send READ command */ - ret = realtek_smi_write_byte(smi, smi->cmd_read); - if (ret) - goto out; - - /* Set ADDR[7:0] */ - ret = realtek_smi_write_byte(smi, addr & 0xff); - if (ret) - goto out; - - /* Set ADDR[15:8] */ - ret = realtek_smi_write_byte(smi, addr >> 8); - if (ret) - goto out; - - /* Read DATA[7:0] */ - realtek_smi_read_byte0(smi, &lo); - /* Read DATA[15:8] */ - realtek_smi_read_byte1(smi, &hi); - - *data = ((u32)lo) | (((u32)hi) << 8); - - ret = 0; - - out: - realtek_smi_stop(smi); - spin_unlock_irqrestore(&smi->lock, flags); - - return ret; -} - -static int realtek_smi_write_reg(struct realtek_smi *smi, - u32 addr, u32 data, bool ack) -{ - unsigned long flags; - int ret; - - spin_lock_irqsave(&smi->lock, flags); - - realtek_smi_start(smi); - - /* Send WRITE command */ - ret = realtek_smi_write_byte(smi, smi->cmd_write); - if (ret) - goto out; - - /* Set ADDR[7:0] */ - ret = realtek_smi_write_byte(smi, addr & 0xff); - if (ret) - goto out; - - /* Set ADDR[15:8] */ - ret = realtek_smi_write_byte(smi, addr >> 8); - if (ret) - goto out; - - /* Write DATA[7:0] */ - ret = realtek_smi_write_byte(smi, data & 0xff); - if (ret) - goto out; - - /* Write DATA[15:8] */ - if (ack) - ret = realtek_smi_write_byte(smi, data >> 8); - else - ret = realtek_smi_write_byte_noack(smi, data >> 8); - if (ret) - goto out; - - ret = 0; - - out: - realtek_smi_stop(smi); - spin_unlock_irqrestore(&smi->lock, flags); - - return ret; -} - -/* There is one single case when we need to use this accessor and that - * is when issueing soft reset. Since the device reset as soon as we write - * that bit, no ACK will come back for natural reasons. - */ -int realtek_smi_write_reg_noack(struct realtek_smi *smi, u32 addr, - u32 data) -{ - return realtek_smi_write_reg(smi, addr, data, false); -} -EXPORT_SYMBOL_GPL(realtek_smi_write_reg_noack); - -/* Regmap accessors */ - -static int realtek_smi_write(void *ctx, u32 reg, u32 val) -{ - struct realtek_smi *smi = ctx; - - return realtek_smi_write_reg(smi, reg, val, true); -} - -static int realtek_smi_read(void *ctx, u32 reg, u32 *val) -{ - struct realtek_smi *smi = ctx; - - return realtek_smi_read_reg(smi, reg, val); -} - -static const struct regmap_config realtek_smi_mdio_regmap_config = { - .reg_bits = 10, /* A4..A0 R4..R0 */ - .val_bits = 16, - .reg_stride = 1, - /* PHY regs are at 0x8000 */ - .max_register = 0xffff, - .reg_format_endian = REGMAP_ENDIAN_BIG, - .reg_read = realtek_smi_read, - .reg_write = realtek_smi_write, - .cache_type = REGCACHE_NONE, -}; - -static int realtek_smi_mdio_read(struct mii_bus *bus, int addr, int regnum) -{ - struct realtek_smi *smi = bus->priv; - - return smi->ops->phy_read(smi, addr, regnum); -} - -static int realtek_smi_mdio_write(struct mii_bus *bus, int addr, int regnum, - u16 val) -{ - struct realtek_smi *smi = bus->priv; - - return smi->ops->phy_write(smi, addr, regnum, val); -} - -int realtek_smi_setup_mdio(struct realtek_smi *smi) -{ - struct device_node *mdio_np; - int ret; - - mdio_np = of_get_compatible_child(smi->dev->of_node, "realtek,smi-mdio"); - if (!mdio_np) { - dev_err(smi->dev, "no MDIO bus node\n"); - return -ENODEV; - } - - smi->slave_mii_bus = devm_mdiobus_alloc(smi->dev); - if (!smi->slave_mii_bus) { - ret = -ENOMEM; - goto err_put_node; - } - smi->slave_mii_bus->priv = smi; - smi->slave_mii_bus->name = "SMI slave MII"; - smi->slave_mii_bus->read = realtek_smi_mdio_read; - smi->slave_mii_bus->write = realtek_smi_mdio_write; - snprintf(smi->slave_mii_bus->id, MII_BUS_ID_SIZE, "SMI-%d", - smi->ds->index); - smi->slave_mii_bus->dev.of_node = mdio_np; - smi->slave_mii_bus->parent = smi->dev; - smi->ds->slave_mii_bus = smi->slave_mii_bus; - - ret = devm_of_mdiobus_register(smi->dev, smi->slave_mii_bus, mdio_np); - if (ret) { - dev_err(smi->dev, "unable to register MDIO bus %s\n", - smi->slave_mii_bus->id); - goto err_put_node; - } - - return 0; - -err_put_node: - of_node_put(mdio_np); - - return ret; -} - -static int realtek_smi_probe(struct platform_device *pdev) -{ - const struct realtek_smi_variant *var; - struct device *dev = &pdev->dev; - struct realtek_smi *smi; - struct device_node *np; - int ret; - - var = of_device_get_match_data(dev); - np = dev->of_node; - - smi = devm_kzalloc(dev, sizeof(*smi) + var->chip_data_sz, GFP_KERNEL); - if (!smi) - return -ENOMEM; - smi->chip_data = (void *)smi + sizeof(*smi); - smi->map = devm_regmap_init(dev, NULL, smi, - &realtek_smi_mdio_regmap_config); - if (IS_ERR(smi->map)) { - ret = PTR_ERR(smi->map); - dev_err(dev, "regmap init failed: %d\n", ret); - return ret; - } - - /* Link forward and backward */ - smi->dev = dev; - smi->clk_delay = var->clk_delay; - smi->cmd_read = var->cmd_read; - smi->cmd_write = var->cmd_write; - smi->ops = var->ops; - - dev_set_drvdata(dev, smi); - spin_lock_init(&smi->lock); - - /* TODO: if power is software controlled, set up any regulators here */ - - /* Assert then deassert RESET */ - smi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); - if (IS_ERR(smi->reset)) { - dev_err(dev, "failed to get RESET GPIO\n"); - return PTR_ERR(smi->reset); - } - msleep(REALTEK_SMI_HW_STOP_DELAY); - gpiod_set_value(smi->reset, 0); - msleep(REALTEK_SMI_HW_START_DELAY); - dev_info(dev, "deasserted RESET\n"); - - /* Fetch MDIO pins */ - smi->mdc = devm_gpiod_get_optional(dev, "mdc", GPIOD_OUT_LOW); - if (IS_ERR(smi->mdc)) - return PTR_ERR(smi->mdc); - smi->mdio = devm_gpiod_get_optional(dev, "mdio", GPIOD_OUT_LOW); - if (IS_ERR(smi->mdio)) - return PTR_ERR(smi->mdio); - - smi->leds_disabled = of_property_read_bool(np, "realtek,disable-leds"); - - ret = smi->ops->detect(smi); - if (ret) { - dev_err(dev, "unable to detect switch\n"); - return ret; - } - - smi->ds = devm_kzalloc(dev, sizeof(*smi->ds), GFP_KERNEL); - if (!smi->ds) - return -ENOMEM; - - smi->ds->dev = dev; - smi->ds->num_ports = smi->num_ports; - smi->ds->priv = smi; - - smi->ds->ops = var->ds_ops; - ret = dsa_register_switch(smi->ds); - if (ret) { - dev_err_probe(dev, ret, "unable to register switch\n"); - return ret; - } - return 0; -} - -static int realtek_smi_remove(struct platform_device *pdev) -{ - struct realtek_smi *smi = platform_get_drvdata(pdev); - - if (!smi) - return 0; - - dsa_unregister_switch(smi->ds); - if (smi->slave_mii_bus) - of_node_put(smi->slave_mii_bus->dev.of_node); - gpiod_set_value(smi->reset, 1); - - platform_set_drvdata(pdev, NULL); - - return 0; -} - -static void realtek_smi_shutdown(struct platform_device *pdev) -{ - struct realtek_smi *smi = platform_get_drvdata(pdev); - - if (!smi) - return; - - dsa_switch_shutdown(smi->ds); - - platform_set_drvdata(pdev, NULL); -} - -static const struct of_device_id realtek_smi_of_match[] = { - { - .compatible = "realtek,rtl8366rb", - .data = &rtl8366rb_variant, - }, - { - /* FIXME: add support for RTL8366S and more */ - .compatible = "realtek,rtl8366s", - .data = NULL, - }, - { - .compatible = "realtek,rtl8365mb", - .data = &rtl8365mb_variant, - }, - { /* sentinel */ }, -}; -MODULE_DEVICE_TABLE(of, realtek_smi_of_match); - -static struct platform_driver realtek_smi_driver = { - .driver = { - .name = "realtek-smi", - .of_match_table = of_match_ptr(realtek_smi_of_match), - }, - .probe = realtek_smi_probe, - .remove = realtek_smi_remove, - .shutdown = realtek_smi_shutdown, -}; -module_platform_driver(realtek_smi_driver); - -MODULE_LICENSE("GPL"); |