From: Florian Fainelli f.fainelli@gmail.com
[ Upstream commit b78ac6ecd1b6b46f8767cbafa95a7b0b51b87ad8 ]
Allow the configuration of the MDIO clock divider when the Device Tree contains 'clock-frequency' property (similar to I2C and SPI buses). Because the hardware may have lost its state during suspend/resume, re-apply the MDIO clock divider upon resumption.
Signed-off-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../bindings/net/brcm,unimac-mdio.txt | 3 + drivers/net/phy/mdio-bcm-unimac.c | 83 ++++++++++++++++++- 2 files changed, 84 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/brcm,unimac-mdio.txt b/Documentation/devicetree/bindings/net/brcm,unimac-mdio.txt index 4648948f7c3b8..e15589f477876 100644 --- a/Documentation/devicetree/bindings/net/brcm,unimac-mdio.txt +++ b/Documentation/devicetree/bindings/net/brcm,unimac-mdio.txt @@ -19,6 +19,9 @@ Optional properties: - interrupt-names: must be "mdio_done_error" when there is a share interrupt fed to this hardware block, or must be "mdio_done" for the first interrupt and "mdio_error" for the second when there are separate interrupts +- clocks: A reference to the clock supplying the MDIO bus controller +- clock-frequency: the MDIO bus clock that must be output by the MDIO bus + hardware, if absent, the default hardware values are used
Child nodes of this MDIO bus controller node are standard Ethernet PHY device nodes as described in Documentation/devicetree/bindings/net/phy.txt diff --git a/drivers/net/phy/mdio-bcm-unimac.c b/drivers/net/phy/mdio-bcm-unimac.c index 08e0647b85e23..f9d98a6e67bc4 100644 --- a/drivers/net/phy/mdio-bcm-unimac.c +++ b/drivers/net/phy/mdio-bcm-unimac.c @@ -16,6 +16,7 @@ #include <linux/module.h> #include <linux/io.h> #include <linux/delay.h> +#include <linux/clk.h>
#include <linux/of.h> #include <linux/of_platform.h> @@ -45,6 +46,8 @@ struct unimac_mdio_priv { void __iomem *base; int (*wait_func) (void *wait_func_data); void *wait_func_data; + struct clk *clk; + u32 clk_freq; };
static inline u32 unimac_mdio_readl(struct unimac_mdio_priv *priv, u32 offset) @@ -189,6 +192,35 @@ static int unimac_mdio_reset(struct mii_bus *bus) return 0; }
+static void unimac_mdio_clk_set(struct unimac_mdio_priv *priv) +{ + unsigned long rate; + u32 reg, div; + + /* Keep the hardware default values */ + if (!priv->clk_freq) + return; + + if (!priv->clk) + rate = 250000000; + else + rate = clk_get_rate(priv->clk); + + div = (rate / (2 * priv->clk_freq)) - 1; + if (div & ~MDIO_CLK_DIV_MASK) { + pr_warn("Incorrect MDIO clock frequency, ignoring\n"); + return; + } + + /* The MDIO clock is the reference clock (typicaly 250Mhz) divided by + * 2 x (MDIO_CLK_DIV + 1) + */ + reg = unimac_mdio_readl(priv, MDIO_CFG); + reg &= ~(MDIO_CLK_DIV_MASK << MDIO_CLK_DIV_SHIFT); + reg |= div << MDIO_CLK_DIV_SHIFT; + unimac_mdio_writel(priv, reg, MDIO_CFG); +} + static int unimac_mdio_probe(struct platform_device *pdev) { struct unimac_mdio_pdata *pdata = pdev->dev.platform_data; @@ -215,9 +247,26 @@ static int unimac_mdio_probe(struct platform_device *pdev) return -ENOMEM; }
+ priv->clk = devm_clk_get(&pdev->dev, NULL); + if (PTR_ERR(priv->clk) == -EPROBE_DEFER) + return PTR_ERR(priv->clk); + else + priv->clk = NULL; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq)) + priv->clk_freq = 0; + + unimac_mdio_clk_set(priv); + priv->mii_bus = mdiobus_alloc(); - if (!priv->mii_bus) - return -ENOMEM; + if (!priv->mii_bus) { + ret = -ENOMEM; + goto out_clk_disable; + }
bus = priv->mii_bus; bus->priv = priv; @@ -251,6 +300,8 @@ static int unimac_mdio_probe(struct platform_device *pdev)
out_mdio_free: mdiobus_free(bus); +out_clk_disable: + clk_disable_unprepare(priv->clk); return ret; }
@@ -260,10 +311,37 @@ static int unimac_mdio_remove(struct platform_device *pdev)
mdiobus_unregister(priv->mii_bus); mdiobus_free(priv->mii_bus); + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int unimac_mdio_suspend(struct device *d) +{ + struct unimac_mdio_priv *priv = dev_get_drvdata(d); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int unimac_mdio_resume(struct device *d) +{ + struct unimac_mdio_priv *priv = dev_get_drvdata(d); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + unimac_mdio_clk_set(priv);
return 0; }
+static SIMPLE_DEV_PM_OPS(unimac_mdio_pm_ops, + unimac_mdio_suspend, unimac_mdio_resume); + static const struct of_device_id unimac_mdio_ids[] = { { .compatible = "brcm,genet-mdio-v5", }, { .compatible = "brcm,genet-mdio-v4", }, @@ -279,6 +357,7 @@ static struct platform_driver unimac_mdio_driver = { .driver = { .name = UNIMAC_MDIO_DRV_NAME, .of_match_table = unimac_mdio_ids, + .pm = &unimac_mdio_pm_ops, }, .probe = unimac_mdio_probe, .remove = unimac_mdio_remove,