Re: [PATCH v1] net: phy: at803x: add cable test support
From: Andrew Lunn <andrew@lunn.ch>
Date: 2020-05-13 13:32:15
Also in:
lkml
On Wed, May 13, 2020 at 02:06:48PM +0200, Oleksij Rempel wrote:
The cable test seems to be support by all of currently support Atherso PHYs, so add support for all of them. This patch was tested only on AR9331 PHY with following results: - No cable is detected as short - A 15m long cable connected only on one side is detected as 9m open.
That sounds wrong. What about a shorted 15m cable? Is it also 9m? Do you have any other long cables you can test with? Is it always 1/2 the cable length?
quoted hunk ↗ jump to hunk
- A cable test with active link partner will provide no usable results. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> --- drivers/net/phy/at803x.c | 141 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+)diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c index f4fec5f644e91..03ec500defb34 100644 --- a/drivers/net/phy/at803x.c +++ b/drivers/net/phy/at803x.c@@ -7,11 +7,13 @@ * Author: Matus Ujhelyi <ujhelyi.m@gmail.com> */ +#include <linux/bitfield.h> #include <linux/phy.h> #include <linux/module.h> #include <linux/string.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> +#include <linux/ethtool_netlink.h> #include <linux/of_gpio.h> #include <linux/bitfield.h> #include <linux/gpio/consumer.h>@@ -48,6 +50,20 @@ #define AT803X_SMART_SPEED_BYPASS_TIMER BIT(1) #define AT803X_LED_CONTROL 0x18 +/* Cable Tester Contol Register */ +#define AT803X_CABLE_DIAG_CTRL 0x16 +#define AT803X_CABLE_DIAG_MDI_PAIR GENMASK(9, 8) +#define AT803X_CABLE_DIAG_EN BIT(0) + +/* Cable Tester Status Register */ +#define AT803X_CABLE_DIAG_STATUS 0x1c +#define AT803X_CABLE_DIAG_RESULT GENMASK(9, 8) +#define AT803X_CABLE_DIAG_RESULT_OK 0 +#define AT803X_CABLE_DIAG_RESULT_SHORT 1 +#define AT803X_CABLE_DIAG_RESULT_OPEN 2 +#define AT803X_CABLE_DIAG_RESULT_FAIL 3 +#define AT803X_CABLE_DIAG_DTIME GENMASK(7, 0) + #define AT803X_DEVICE_ADDR 0x03 #define AT803X_LOC_MAC_ADDR_0_15_OFFSET 0x804C #define AT803X_LOC_MAC_ADDR_16_31_OFFSET 0x804B@@ -122,6 +138,7 @@ MODULE_AUTHOR("Matus Ujhelyi"); MODULE_LICENSE("GPL"); struct at803x_priv { + struct phy_device *phydev; int flags; #define AT803X_KEEP_PLL_ENABLED BIT(0) /* don't turn off internal PLL */ u16 clk_25m_reg;@@ -129,6 +146,9 @@ struct at803x_priv { struct regulator_dev *vddio_rdev; struct regulator_dev *vddh_rdev; struct regulator *vddio; + struct work_struct cable_test_work; + bool cable_test_finished; + int cable_test_ret; }; struct at803x_context {@@ -168,6 +188,113 @@ static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg, return phy_write(phydev, AT803X_DEBUG_DATA, val); }
+static void at803x_cable_test_work(struct work_struct *work)
+{
+ struct at803x_priv *priv = container_of(work, struct at803x_priv,
+ cable_test_work);
+ struct phy_device *phydev = priv->phydev;
+ int i, ret = 0, pairs = 4;
+
+ if (phydev->phy_id == ATH9331_PHY_ID)
+ pairs = 2;
+
+ for (i = 0; i < pairs; i++) {
+ ret = at803x_cable_test_pair(phydev, i);
+ if (ret)
+ break;
+ }
+
+ priv->cable_test_ret = ret;
+ priv->cable_test_finished = true;
+
+ phy_queue_state_machine(phydev, 0);
+}
+
+static int at803x_cable_test_start(struct phy_device *phydev)
+{
+ struct at803x_priv *priv = phydev->priv;
+
+ if (!priv->cable_test_finished) {
+ phydev_err(phydev, "cable test is already running\n");
+ return -EIO;
+ }
+
+ priv->cable_test_finished = false;
+ schedule_work(&priv->cable_test_work);
You don't need the work queue. You cannot spend a long time in
at803x_cable_test_start(), but you can in
at803x_cable_test_get_status(). So start the first the measurement of
the first pair in at803x_cable_test_start(), and do the rest in
of the work in at803x_cable_test_get_status().
If we see there is a common pattern of wanting
at803x_cable_test_get_status() to run immediately, not one second
later, we can change to core to support that.
Andrew