[PATCH net-next v2 01/10] net: dsa: lan9303: Fixed MDIO interface

From: Egil Hjelmeland
Date: Tue Jul 25 2017 - 12:40:04 EST


Fixes after testing on actual HW:

- lan9303_mdio_write()/_read() must multiply register number
by 4 to get offset

- Indirect access (PMI) to phy register only work in I2C mode. In
MDIO mode phy registers must be accessed directly. Introduced
struct lan9303_phy_ops to handle the two modes. Renamed functions
to clarify.

- lan9303_detect_phy_setup() : Failed MDIO read return 0xffff.
Handle that.

Signed-off-by: Egil Hjelmeland <privat@xxxxxxxxxxxxxxxxxx>
---
drivers/net/dsa/lan9303-core.c | 42 +++++++++++++++++++++++++++---------------
drivers/net/dsa/lan9303.h | 11 +++++++++++
drivers/net/dsa/lan9303_i2c.c | 2 ++
drivers/net/dsa/lan9303_mdio.c | 34 ++++++++++++++++++++++++++++++++++
4 files changed, 74 insertions(+), 15 deletions(-)

diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
index cd76e61f1fca..e622db586c3d 100644
--- a/drivers/net/dsa/lan9303-core.c
+++ b/drivers/net/dsa/lan9303-core.c
@@ -20,6 +20,9 @@

#include "lan9303.h"

+/* 13.2 System Control and Status Registers
+ * Multiply register number by 4 to get address offset.
+ */
#define LAN9303_CHIP_REV 0x14
# define LAN9303_CHIP_ID 0x9303
#define LAN9303_IRQ_CFG 0x15
@@ -53,6 +56,9 @@
#define LAN9303_VIRT_PHY_BASE 0x70
#define LAN9303_VIRT_SPECIAL_CTRL 0x77

+/*13.4 Switch Fabric Control and Status Registers
+ * Accessed indirectly via SWITCH_CSR_CMD, SWITCH_CSR_DATA.
+ */
#define LAN9303_SW_DEV_ID 0x0000
#define LAN9303_SW_RESET 0x0001
#define LAN9303_SW_RESET_RESET BIT(0)
@@ -242,7 +248,7 @@ static int lan9303_virt_phy_reg_write(struct lan9303 *chip, int regnum, u16 val)
return regmap_write(chip->regmap, LAN9303_VIRT_PHY_BASE + regnum, val);
}

-static int lan9303_port_phy_reg_wait_for_completion(struct lan9303 *chip)
+static int lan9303_indirect_phy_wait_for_completion(struct lan9303 *chip)
{
int ret, i;
u32 reg;
@@ -262,7 +268,7 @@ static int lan9303_port_phy_reg_wait_for_completion(struct lan9303 *chip)
return -EIO;
}

-static int lan9303_port_phy_reg_read(struct lan9303 *chip, int addr, int regnum)
+static int lan9303_indirect_phy_read(struct lan9303 *chip, int addr, int regnum)
{
int ret;
u32 val;
@@ -272,7 +278,7 @@ static int lan9303_port_phy_reg_read(struct lan9303 *chip, int addr, int regnum)

mutex_lock(&chip->indirect_mutex);

- ret = lan9303_port_phy_reg_wait_for_completion(chip);
+ ret = lan9303_indirect_phy_wait_for_completion(chip);
if (ret)
goto on_error;

@@ -281,7 +287,7 @@ static int lan9303_port_phy_reg_read(struct lan9303 *chip, int addr, int regnum)
if (ret)
goto on_error;

- ret = lan9303_port_phy_reg_wait_for_completion(chip);
+ ret = lan9303_indirect_phy_wait_for_completion(chip);
if (ret)
goto on_error;

@@ -299,8 +305,8 @@ static int lan9303_port_phy_reg_read(struct lan9303 *chip, int addr, int regnum)
return ret;
}

-static int lan9303_phy_reg_write(struct lan9303 *chip, int addr, int regnum,
- unsigned int val)
+static int lan9303_indirect_phy_write(struct lan9303 *chip, int addr,
+ int regnum, u16 val)
{
int ret;
u32 reg;
@@ -311,7 +317,7 @@ static int lan9303_phy_reg_write(struct lan9303 *chip, int addr, int regnum,

mutex_lock(&chip->indirect_mutex);

- ret = lan9303_port_phy_reg_wait_for_completion(chip);
+ ret = lan9303_indirect_phy_wait_for_completion(chip);
if (ret)
goto on_error;

@@ -328,6 +334,11 @@ static int lan9303_phy_reg_write(struct lan9303 *chip, int addr, int regnum,
return ret;
}

+const struct lan9303_phy_ops lan9303_indirect_phy_ops = {
+ .phy_read = lan9303_indirect_phy_read,
+ .phy_write = lan9303_indirect_phy_write,
+};
+
static int lan9303_switch_wait_for_completion(struct lan9303 *chip)
{
int ret, i;
@@ -427,14 +438,15 @@ static int lan9303_detect_phy_setup(struct lan9303 *chip)
* Special reg 18 of phy 3 reads as 0x0000, if 'phy_addr_sel_strap' is 0
* and the IDs are 0-1-2, else it contains something different from
* 0x0000, which means 'phy_addr_sel_strap' is 1 and the IDs are 1-2-3.
+ * 0xffff is returned for failed MDIO access.
*/
- reg = lan9303_port_phy_reg_read(chip, 3, MII_LAN911X_SPECIAL_MODES);
+ reg = chip->ops->phy_read(chip, 3, MII_LAN911X_SPECIAL_MODES);
if (reg < 0) {
dev_err(chip->dev, "Failed to detect phy config: %d\n", reg);
return reg;
}

- if (reg != 0)
+ if ((reg != 0) && (reg != 0xffff))
chip->phy_addr_sel_strap = 1;
else
chip->phy_addr_sel_strap = 0;
@@ -719,7 +731,7 @@ static int lan9303_phy_read(struct dsa_switch *ds, int phy, int regnum)
if (phy > phy_base + 2)
return -ENODEV;

- return lan9303_port_phy_reg_read(chip, phy, regnum);
+ return chip->ops->phy_read(chip, phy, regnum);
}

static int lan9303_phy_write(struct dsa_switch *ds, int phy, int regnum,
@@ -733,7 +745,7 @@ static int lan9303_phy_write(struct dsa_switch *ds, int phy, int regnum,
if (phy > phy_base + 2)
return -ENODEV;

- return lan9303_phy_reg_write(chip, phy, regnum, val);
+ return chip->ops->phy_write(chip, phy, regnum, val);
}

static int lan9303_port_enable(struct dsa_switch *ds, int port,
@@ -766,13 +778,13 @@ static void lan9303_port_disable(struct dsa_switch *ds, int port,
switch (port) {
case 1:
lan9303_disable_packet_processing(chip, LAN9303_PORT_1_OFFSET);
- lan9303_phy_reg_write(chip, chip->phy_addr_sel_strap + 1,
- MII_BMCR, BMCR_PDOWN);
+ lan9303_phy_write(ds, chip->phy_addr_sel_strap + 1,
+ MII_BMCR, BMCR_PDOWN);
break;
case 2:
lan9303_disable_packet_processing(chip, LAN9303_PORT_2_OFFSET);
- lan9303_phy_reg_write(chip, chip->phy_addr_sel_strap + 2,
- MII_BMCR, BMCR_PDOWN);
+ lan9303_phy_write(ds, chip->phy_addr_sel_strap + 2,
+ MII_BMCR, BMCR_PDOWN);
break;
default:
dev_dbg(chip->dev,
diff --git a/drivers/net/dsa/lan9303.h b/drivers/net/dsa/lan9303.h
index d1512dad2d90..444d00b460e1 100644
--- a/drivers/net/dsa/lan9303.h
+++ b/drivers/net/dsa/lan9303.h
@@ -2,6 +2,15 @@
#include <linux/device.h>
#include <net/dsa.h>

+struct lan9303;
+
+struct lan9303_phy_ops {
+ /* PHY 1 &2 access*/
+ int (*phy_read)(struct lan9303 *chip, int port, int regnum);
+ int (*phy_write)(struct lan9303 *chip, int port,
+ int regnum, u16 val);
+};
+
struct lan9303 {
struct device *dev;
struct regmap *regmap;
@@ -11,9 +20,11 @@ struct lan9303 {
bool phy_addr_sel_strap;
struct dsa_switch *ds;
struct mutex indirect_mutex; /* protect indexed register access */
+ const struct lan9303_phy_ops *ops;
};

extern const struct regmap_access_table lan9303_register_set;
+extern const struct lan9303_phy_ops lan9303_indirect_phy_ops;

int lan9303_probe(struct lan9303 *chip, struct device_node *np);
int lan9303_remove(struct lan9303 *chip);
diff --git a/drivers/net/dsa/lan9303_i2c.c b/drivers/net/dsa/lan9303_i2c.c
index ab3ce0da5071..24ec20f7f444 100644
--- a/drivers/net/dsa/lan9303_i2c.c
+++ b/drivers/net/dsa/lan9303_i2c.c
@@ -63,6 +63,8 @@ static int lan9303_i2c_probe(struct i2c_client *client,
i2c_set_clientdata(client, sw_dev);
sw_dev->chip.dev = &client->dev;

+ sw_dev->chip.ops = &lan9303_indirect_phy_ops;
+
ret = lan9303_probe(&sw_dev->chip, client->dev.of_node);
if (ret != 0)
return ret;
diff --git a/drivers/net/dsa/lan9303_mdio.c b/drivers/net/dsa/lan9303_mdio.c
index 93c36c0541cf..94df12c5362f 100644
--- a/drivers/net/dsa/lan9303_mdio.c
+++ b/drivers/net/dsa/lan9303_mdio.c
@@ -39,6 +39,7 @@ static void lan9303_mdio_real_write(struct mdio_device *mdio, int reg, u16 val)
static int lan9303_mdio_write(void *ctx, uint32_t reg, uint32_t val)
{
struct lan9303_mdio *sw_dev = (struct lan9303_mdio *)ctx;
+ reg <<= 2; /* reg num to offset */

mutex_lock(&sw_dev->device->bus->mdio_lock);
lan9303_mdio_real_write(sw_dev->device, reg, val & 0xffff);
@@ -56,6 +57,7 @@ static u16 lan9303_mdio_real_read(struct mdio_device *mdio, int reg)
static int lan9303_mdio_read(void *ctx, uint32_t reg, uint32_t *val)
{
struct lan9303_mdio *sw_dev = (struct lan9303_mdio *)ctx;
+ reg <<= 2; /* reg num to offset */

mutex_lock(&sw_dev->device->bus->mdio_lock);
*val = lan9303_mdio_real_read(sw_dev->device, reg);
@@ -65,6 +67,36 @@ static int lan9303_mdio_read(void *ctx, uint32_t reg, uint32_t *val)
return 0;
}

+int lan9303_mdio_phy_write(struct lan9303 *chip, int phy, int regnum, u16 val)
+{
+ struct lan9303_mdio *sw_dev = dev_get_drvdata(chip->dev);
+ struct mdio_device *mdio = sw_dev->device;
+
+ mutex_lock(&mdio->bus->mdio_lock);
+ mdio->bus->write(mdio->bus, phy, regnum, val);
+ mutex_unlock(&mdio->bus->mdio_lock);
+
+ return 0;
+}
+
+int lan9303_mdio_phy_read(struct lan9303 *chip, int phy, int reg)
+{
+ struct lan9303_mdio *sw_dev = dev_get_drvdata(chip->dev);
+ struct mdio_device *mdio = sw_dev->device;
+ int val;
+
+ mutex_lock(&mdio->bus->mdio_lock);
+ val = mdio->bus->read(mdio->bus, phy, reg);
+ mutex_unlock(&mdio->bus->mdio_lock);
+
+ return val;
+}
+
+static const struct lan9303_phy_ops lan9303_mdio_phy_ops = {
+ .phy_read = lan9303_mdio_phy_read,
+ .phy_write = lan9303_mdio_phy_write,
+};
+
static const struct regmap_config lan9303_mdio_regmap_config = {
.reg_bits = 8,
.val_bits = 32,
@@ -106,6 +138,8 @@ static int lan9303_mdio_probe(struct mdio_device *mdiodev)
dev_set_drvdata(&mdiodev->dev, sw_dev);
sw_dev->chip.dev = &mdiodev->dev;

+ sw_dev->chip.ops = &lan9303_mdio_phy_ops;
+
ret = lan9303_probe(&sw_dev->chip, mdiodev->dev.of_node);
if (ret != 0)
return ret;
--
2.11.0