luck/tmp_suning_uos_patched
1
0
Fork 1
Code Issues Pull Requests Packages Projects Releases Wiki Activity
059d8442ea
tmp_suning_uos_patched/drivers/net/dsa/realtek-smi.c
Johan Hovold 3f1bb6abdf net: dsa: realtek-smi: fix OF child-node lookup 
Use the new of_get_compatible_child() helper to look up child nodes to
avoid ever matching non-child nodes elsewhere in the tree.

Also fix up the related struct device_node leaks.

Fixes: d8652956cf ("net: dsa: realtek-smi: Add Realtek SMI driver")
Cc: stable <stable@vger.kernel.org>     # 4.19: 36156f9241
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 14:04:49 -08:00

498 lines
11 KiB
C
Raw Blame History

// 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.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 = of_mdiobus_register(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), GFP_KERNEL);
if (!smi)
return -ENOMEM;
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 = dsa_switch_alloc(dev, smi->num_ports);
if (!smi->ds)
return -ENOMEM;
smi->ds->priv = smi;
smi->ds->ops = var->ds_ops;
ret = dsa_register_switch(smi->ds);
if (ret) {
dev_err(dev, "unable to register switch ret = %d\n", ret);
return ret;
}
return 0;
}
static int realtek_smi_remove(struct platform_device *pdev)
{
struct realtek_smi *smi = dev_get_drvdata(&pdev->dev);
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);
return 0;
}
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,
},
{ /* 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,
};
module_platform_driver(realtek_smi_driver);
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink