[PATCH v8 2/3] net: hisilicon: new hip04 MDIO driver

2014-04-21 10:58 GMT-07:00 Sergei Shtylyov [off-list ref]:

Hello.


On 04/19/2014 05:12 AM, Zhangfei Gao wrote:

quoted

Hisilicon hip04 platform mdio driver
Reuse Marvell phy drivers/net/phy/marvell.c

quoted

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>

[...]

quoted

diff --git a/drivers/net/ethernet/hisilicon/hip04_mdio.c

b/drivers/net/ethernet/hisilicon/hip04_mdio.c
new file mode 100644
index 0000000..19826a3

--- /dev/null
+++ b/drivers/net/ethernet/hisilicon/hip04_mdio.c

@@ -0,0 +1,185 @@
+

   Empty line not needed here.

quoted

+/* Copyright (c) 2014 Linaro Ltd.
+ * Copyright (c) 2014 Hisilicon Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */

[...]

quoted

+static int hip04_mdio_reset(struct mii_bus *bus)
+{
+       int temp, err, i;
+
+       for (i = 0; i < PHY_MAX_ADDR; i++) {
+               hip04_mdio_write(bus, i, 22, 0);

   Why? What kind of a register this is? <uapi/linux/mii.h> tells me it's
MII_SREVISION...

I think this rather means clause 22 as opposed to clause 45.

quoted

+               temp = hip04_mdio_read(bus, i, MII_BMCR);

   You're not checking for error...

quoted

+               temp |= BMCR_RESET;
+               err = hip04_mdio_write(bus, i, MII_BMCR, temp);

   Hmm, why you're open coding BMCR reset? There's phy_init_hw() doing this
correctly...

Except that this runs way before we have created the PHY driver, so we
can't use that function just yet. I already asked about this, and he
explained that this was because the PHY devices he uses are not
responding correcty to MII_PHYSID1/2 reads.

quoted

+               if (err < 0)
+                       return err;
+       }
+
+       mdelay(500);
+       return 0;
+}
+
+static int hip04_mdio_probe(struct platform_device *pdev)
+{
+       struct resource *r;
+       struct mii_bus *bus;
+       struct hip04_mdio_priv *priv;
+       int ret;
+
+       bus = mdiobus_alloc_size(sizeof(struct hip04_mdio_priv));
+       if (!bus) {
+               dev_err(&pdev->dev, "Cannot allocate MDIO bus\n");
+               return -ENOMEM;
+       }
+
+       bus->name = "hip04_mdio_bus";
+       bus->read = hip04_mdio_read;
+       bus->write = hip04_mdio_write;
+       bus->reset = hip04_mdio_reset;

   Ah... However I don't think it a good implementation of that bus
method...

[...]

WBR, Sergei

-- 
Florian