[PATCH v2 2/4] usb: mxs-phy: change clock usage for i.mx6q
Peter Chen
peter.chen at freescale.com
Tue Jan 15 01:08:35 EST 2013
For mxs-phy user i.mx6q, the PHY's clock is controlled by
hardware automatically, the software only needs to enable it
at probe, disable it at remove. But other mxs-phy users need
to control that clock runtime, so we hardcode clk on/off,
and give a reserved bit for clk on/off at clk code for i.mx6q.
Signed-off-by: Peter Chen <peter.chen at freescale.com>
---
Changes for v2:
- Only control gate bit for phy clk control
- Only open the gate at probe, and close the gate at remove
Documentation/devicetree/bindings/usb/mxs-phy.txt | 2 +
arch/arm/boot/dts/imx6q.dtsi | 2 +
drivers/usb/otg/mxs-phy.c | 61 +++++++++++++++++++++
3 files changed, 65 insertions(+), 0 deletions(-)
diff --git a/Documentation/devicetree/bindings/usb/mxs-phy.txt b/Documentation/devicetree/bindings/usb/mxs-phy.txt
index 5835b27..384e700 100644
--- a/Documentation/devicetree/bindings/usb/mxs-phy.txt
+++ b/Documentation/devicetree/bindings/usb/mxs-phy.txt
@@ -4,10 +4,12 @@ Required properties:
- compatible: Should be "fsl,imx23-usbphy"
- reg: Should contain registers location and length
- interrupts: Should contain phy interrupt
+- The reg offset for PHY clock at anatop
Example:
usbphy1: usbphy at 020c9000 {
compatible = "fsl,imx6q-usbphy", "fsl,imx23-usbphy";
reg = <0x020c9000 0x1000>;
interrupts = <0 44 0x04>;
+ anatop-phy-reg-offset = <0x10>;
};
diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
index d6265ca..1517e93 100644
--- a/arch/arm/boot/dts/imx6q.dtsi
+++ b/arch/arm/boot/dts/imx6q.dtsi
@@ -519,6 +519,7 @@
reg = <0x020c9000 0x1000>;
interrupts = <0 44 0x04>;
clocks = <&clks 182>;
+ anatop-phy-reg-offset = <0x10>;
};
usbphy2: usbphy at 020ca000 {
@@ -526,6 +527,7 @@
reg = <0x020ca000 0x1000>;
interrupts = <0 45 0x04>;
clocks = <&clks 183>;
+ anatop-phy-reg-offset = <0x20>;
};
snvs at 020cc000 {
diff --git a/drivers/usb/otg/mxs-phy.c b/drivers/usb/otg/mxs-phy.c
index 7630272..49727dd 100644
--- a/drivers/usb/otg/mxs-phy.c
+++ b/drivers/usb/otg/mxs-phy.c
@@ -20,6 +20,9 @@
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
#define DRIVER_NAME "mxs_phy"
@@ -34,6 +37,11 @@
#define BM_USBPHY_CTRL_ENUTMILEVEL2 BIT(14)
#define BM_USBPHY_CTRL_ENHOSTDISCONDETECT BIT(1)
+#define CTRL_SET 0x4
+#define CTRL_CLR 0x8
+
+#define BM_ANADIG_USB_PLL_480_CTRL_EN_USB_CLKS (1 << 6)
+
struct mxs_phy {
struct usb_phy phy;
struct clk *clk;
@@ -108,6 +116,7 @@ static int mxs_phy_probe(struct platform_device *pdev)
void __iomem *base;
struct clk *clk;
struct mxs_phy *mxs_phy;
+ struct regmap *anatop;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
@@ -146,11 +155,63 @@ static int mxs_phy_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, &mxs_phy->phy);
+ /*
+ * At mx6x, USB PHY PLL and its output gate is controlled by hardware.
+ * It just needs to open the gate at init, if the usb device is
+ * in suspend, it will close related PLL automatically without
+ * the gate is on or off.
+ */
+
+ anatop = syscon_regmap_lookup_by_compatible("fsl,imx6q-anatop");
+
+ if (!IS_ERR(anatop)) {
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ u32 phy_reg_offset;
+ int ret;
+
+ ret = of_property_read_u32(np, "anatop-phy-reg-offset",
+ &phy_reg_offset);
+ if (ret) {
+ dev_err(dev, "no anatop-phy-reg-offset property set\n");
+ return -EINVAL;
+ }
+
+ regmap_write(anatop, phy_reg_offset + CTRL_SET,
+ BM_ANADIG_USB_PLL_480_CTRL_EN_USB_CLKS);
+ } else {
+ pr_warn("failed to find fsl,imx6q-anatop regmap\n");
+ }
+
return 0;
}
static int mxs_phy_remove(struct platform_device *pdev)
{
+ struct regmap *anatop;
+
+ /* close the clock gate for USB PHY */
+ anatop = syscon_regmap_lookup_by_compatible("fsl,imx6q-anatop");
+
+ if (!IS_ERR(anatop)) {
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ u32 phy_reg_offset;
+ int ret;
+
+ ret = of_property_read_u32(np, "anatop-phy-reg-offset",
+ &phy_reg_offset);
+ if (ret) {
+ dev_err(dev, "no anatop-phy-reg-offset property set\n");
+ return -EINVAL;
+ }
+
+ regmap_write(anatop, phy_reg_offset + CTRL_CLR,
+ BM_ANADIG_USB_PLL_480_CTRL_EN_USB_CLKS);
+ } else {
+ pr_warn("failed to find fsl,imx6q-anatop regmap\n");
+ }
+
platform_set_drvdata(pdev, NULL);
return 0;
--
1.7.0.4
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