On 01/17/2017 01:11 AM, YUAN Linyu wrote:
>
>
>> -----Original Message-----
>> From: David Miller [mailto:da...@davemloft.net]
>> Sent: Tuesday, January 17, 2017 5:54 AM
>> To: f.faine...@gmail.com
>> Cc: cug...@163.com; and...@lunn.ch; netdev@vger.kernel.org; YUAN Linyu
>> Subject: Re: [PATCH] net: add regs attribute to phy device for user diagnose
>>
>> From: Florian Fainelli <f.faine...@gmail.com>
>> Date: Mon, 16 Jan 2017 12:22:16 -0800
>>
>>>
>>> So why not add support in ethtool for reading PHY registers if you need
>>> it? There are handful of PHY "things" in ethtool, such as reading
>>> counters, configuring downshift etc., adding support for dumping
>>> registers does not sound out of space.
> Thanks, I will try this direction.
>>
>> Agreed.
... on the other hand, having direct RW access to MDIO regs can ease your life
greatly during bring-up / debugging of PHYs.
Attached is a patch we are using to track down PHY problems at register level,
not
for integrating into the kernel but as a handy tool for developers.
Cheers,
Zefir
>From f90fced08ca6094919483b0d9a4bde50053bbbd7 Mon Sep 17 00:00:00 2001
From: Zefir Kurtisi <zefir.kurt...@neratec.com>
Date: Wed, 18 Jan 2017 13:17:42 +0100
Subject: [PATCH] phy_device: add sysfs access to mdio registers
This commit adds a direct RW access to MDIO registers
over sysfs.
It is meant only for debugging and testing of PHYs
at register level.
WARNING: Writing to registers directly in most cases
will interfere with the phylib and/or upper layer
components or even crash your system.
Signed-off-by: Zefir Kurtisi <zefir.kurt...@neratec.com>
---
drivers/net/phy/phy_device.c | 111 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 92b0838..16646763 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -617,10 +617,121 @@ phy_has_fixups_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RO(phy_has_fixups);
+static ssize_t
+mdio_reg_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+ struct mii_bus *bus = to_mii_bus(dev);
+ int regnum;
+ int val;
+
+ if (sscanf(attr->attr.name, "%d", ®num) != 1)
+ return -EINVAL;
+
+ val = mdiobus_read(bus, phydev->mdio.addr, regnum);
+ if (val < 0)
+ return -EIO;
+
+ return sprintf(buf, "0x%.4x\n", val);
+}
+
+static ssize_t mdio_reg_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+ struct mii_bus *bus = to_mii_bus(dev);
+ int regnum;
+ int val;
+ int err;
+
+ if (sscanf(attr->attr.name, "%d", ®num) != 1)
+ return -EINVAL;
+
+ if (sscanf(buf, "%x", &val) != 1)
+ return -EINVAL;
+
+ if (val < 0 || val > 0xffff)
+ return -EINVAL;
+
+ err = mdiobus_write(bus, phydev->mdio.addr, regnum, val);
+ if (err < 0)
+ return -EIO;
+
+ return size;
+}
+
+#define MDIO_REG(_name) \
+ DEVICE_ATTR(_name, (S_IWUSR | S_IRUGO), mdio_reg_show, mdio_reg_store)
+
+static MDIO_REG(0);
+static MDIO_REG(1);
+static MDIO_REG(2);
+static MDIO_REG(3);
+static MDIO_REG(4);
+static MDIO_REG(5);
+static MDIO_REG(6);
+static MDIO_REG(7);
+static MDIO_REG(8);
+static MDIO_REG(9);
+static MDIO_REG(10);
+static MDIO_REG(11);
+static MDIO_REG(12);
+static MDIO_REG(13);
+static MDIO_REG(14);
+static MDIO_REG(15);
+static MDIO_REG(16);
+static MDIO_REG(17);
+static MDIO_REG(18);
+static MDIO_REG(19);
+static MDIO_REG(20);
+static MDIO_REG(21);
+static MDIO_REG(22);
+static MDIO_REG(23);
+static MDIO_REG(24);
+static MDIO_REG(25);
+static MDIO_REG(26);
+static MDIO_REG(27);
+static MDIO_REG(28);
+static MDIO_REG(29);
+static MDIO_REG(30);
+static MDIO_REG(31);
+
static struct attribute *phy_dev_attrs[] = {
&dev_attr_phy_id.attr,
&dev_attr_phy_interface.attr,
&dev_attr_phy_has_fixups.attr,
+ &dev_attr_0.attr,
+ &dev_attr_1.attr,
+ &dev_attr_2.attr,
+ &dev_attr_3.attr,
+ &dev_attr_4.attr,
+ &dev_attr_5.attr,
+ &dev_attr_6.attr,
+ &dev_attr_7.attr,
+ &dev_attr_8.attr,
+ &dev_attr_9.attr,
+ &dev_attr_10.attr,
+ &dev_attr_11.attr,
+ &dev_attr_12.attr,
+ &dev_attr_13.attr,
+ &dev_attr_14.attr,
+ &dev_attr_15.attr,
+ &dev_attr_16.attr,
+ &dev_attr_17.attr,
+ &dev_attr_18.attr,
+ &dev_attr_19.attr,
+ &dev_attr_20.attr,
+ &dev_attr_21.attr,
+ &dev_attr_22.attr,
+ &dev_attr_23.attr,
+ &dev_attr_24.attr,
+ &dev_attr_25.attr,
+ &dev_attr_26.attr,
+ &dev_attr_27.attr,
+ &dev_attr_28.attr,
+ &dev_attr_29.attr,
+ &dev_attr_30.attr,
+ &dev_attr_31.attr,
NULL,
};
ATTRIBUTE_GROUPS(phy_dev);
--
2.7.4
