[PATCH] phy: rcar-gen3-usb3: add support for R-Car Gen3 USB 3.0 PHY
From: Yoshihiro Shimoda
Date: Wed May 24 2017 - 08:06:58 EST
The USB 3.0 PHY modules of R-Car Gen3 SoCs have:
- Spread spectrum clock (ssc).
- Using USB 2.0 EXTAL clock instead of USB 3.0 clock.
- Enabling VBUS detection for usb3.0 peripheral.
So, this driver supports these features.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
This patch is based on the latest linux-phy.git / next branch and
"[PATCH v5 3/3] phy: Group vendor specific phy drivers" patch.
I discussed with Geert-san about this driver on the ML:
https://patchwork.kernel.org/patch/9731759/
.../devicetree/bindings/phy/rcar-gen3-phy-usb3.txt | 47 +++++
MAINTAINERS | 4 +-
drivers/phy/renesas/Kconfig | 7 +
drivers/phy/renesas/Makefile | 1 +
drivers/phy/renesas/phy-rcar-gen3-usb3.c | 207 +++++++++++++++++++++
5 files changed, 264 insertions(+), 2 deletions(-)
create mode 100644 Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb3.txt
create mode 100644 drivers/phy/renesas/phy-rcar-gen3-usb3.c
diff --git a/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb3.txt b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb3.txt
new file mode 100644
index 0000000..e58ba6b
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb3.txt
@@ -0,0 +1,47 @@
+* Renesas R-Car generation 3 USB 3.0 PHY
+
+This file provides information on what the device node for the R-Car generation
+3 USB 3.0 PHY contains.
+If you want to enable spread spectrum clock (ssc), you should use USB_EXTAL
+instead of USB3_CLK. However, if you don't want to these features, you don't
+need this driver.
+
+Required properties:
+- compatible: "renesas,r8a7795-usb3-phy" if the device is a part of an R8A7795
+ SoC.
+ "renesas,r8a7796-usb3-phy" if the device is a part of an R8A7796
+ SoC.
+ "renesas,rcar-gen3-usb3-phy" for a generic R-Car Gen3 compatible
+ device.
+
+ When compatible with the generic version, nodes must list the
+ SoC-specific version corresponding to the platform first
+ followed by the generic version.
+
+- reg: offset and length of the USB 3.0 PHY register block.
+- clocks: A list of phandles and clock-specifier pairs.
+- clock-names: Name of the clocks.
+ - The funcional clock must be "usb3-if".
+ - The usb3's external clock must be "usb3s_clk". If you want to use the ssc,
+ the clock-frequency must be 0.
+ - The usb2's external clock must be "usb_extal". If you want to use the ssc,
+ the clock-frequenvy must not be 0.
+- #phy-cells: see phy-bindings.txt in the same directory, must be <0>.
+
+Optional properties:
+- renesas,ssc-range: Enable/disable spread spectrum clock (ssc) by using
+ the following values as u32:
+ - 0 (or the property doesn't exist): disable the ssc
+ - 4980: enable the ssc as -4980 ppm
+ - 4492: enable the ssc as -4492 ppm
+ - 4003: enable the ssc as -4003 ppm
+
+Example (R-Car H3):
+
+ usb-phy@e65ee000 {
+ compatible = "renesas,r8a7795-usb3-phy",
+ "renesas,rcar-gen3-usb3-phy";
+ reg = <0 0xe65ee000 0 0x90>;
+ clocks = <&cpg CPG_MOD 328>, <&usb3s0_clk>, <&usb_extal>;
+ clock-names = "usb3-if", "usb3s_clk", "usb_extal";
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index a47d3da..d711d53 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10829,11 +10829,11 @@ L: linux-iio@xxxxxxxxxxxxxxx
S: Supported
F: drivers/iio/adc/rcar_gyro_adc.c
-RENESAS USB2 PHY DRIVER
+RENESAS USB PHY DRIVER
M: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
L: linux-renesas-soc@xxxxxxxxxxxxxxx
S: Maintained
-F: drivers/phy/renesas/phy-rcar-gen3-usb2.c
+F: drivers/phy/renesas/phy-rcar-gen3-usb*.c
RESET CONTROLLER FRAMEWORK
M: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
diff --git a/drivers/phy/renesas/Kconfig b/drivers/phy/renesas/Kconfig
index 432e271..4377064 100644
--- a/drivers/phy/renesas/Kconfig
+++ b/drivers/phy/renesas/Kconfig
@@ -15,3 +15,10 @@ config PHY_RCAR_GEN3_USB2
select GENERIC_PHY
help
Support for USB 2.0 PHY found on Renesas R-Car generation 3 SoCs.
+
+config PHY_RCAR_GEN3_USB3
+ tristate "Renesas R-Car generation 3 USB 3.0 PHY driver"
+ depends on ARCH_RENESAS
+ select GENERIC_PHY
+ help
+ Support for USB 3.0 PHY found on Renesas R-Car generation 3 SoCs.
diff --git a/drivers/phy/renesas/Makefile b/drivers/phy/renesas/Makefile
index 695241a..8b60259 100644
--- a/drivers/phy/renesas/Makefile
+++ b/drivers/phy/renesas/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_PHY_RCAR_GEN2) += phy-rcar-gen2.o
obj-$(CONFIG_PHY_RCAR_GEN3_USB2) += phy-rcar-gen3-usb2.o
+obj-$(CONFIG_PHY_RCAR_GEN3_USB3) += phy-rcar-gen3-usb3.o
diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb3.c b/drivers/phy/renesas/phy-rcar-gen3-usb3.c
new file mode 100644
index 0000000..6238417
--- /dev/null
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb3.c
@@ -0,0 +1,207 @@
+/*
+ * Renesas R-Car Gen3 for USB3.0 PHY driver
+ *
+ * Copyright (C) 2017 Renesas Electronics Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#define USB30_CLKSET0 0x034
+#define USB30_CLKSET1 0x036
+#define USB30_SSC_SET 0x038
+#define USB30_VBUS_EN 0x064
+
+#define CLKSET0_RESERVED 0x05c0
+#define CLKSET0_USB_EXTAL (CLKSET0_RESERVED | 0x0002)
+
+#define CLKSET1_PLL_MULTI_SHIFT 6
+#define CLKSET1_PLL_MULTI_USB_EXTAL (0x64 << CLKSET1_PLL_MULTI_SHIFT)
+#define CLKSET1_REF_CLKDIV_USB_EXTAL BIT(3)
+#define CLKSET1_RESERVED_1 BIT(1)
+#define CLKSET1_REF_CLK_SEL_USB_EXTAL 0
+#define CLKSET1_USB_EXTAL (CLKSET1_PLL_MULTI_USB_EXTAL | \
+ CLKSET1_REF_CLKDIV_USB_EXTAL | \
+ CLKSET1_RESERVED_1 | \
+ CLKSET1_REF_CLK_SEL_USB_EXTAL)
+
+#define SSC_SET_SSC_EN BIT(12)
+#define SSC_SET_RANGE_SHIFT 9
+#define SSC_SET_RANGE_4980 (0x0 << SSC_SET_RANGE_SHIFT)
+#define SSC_SET_RANGE_4492 (0x1 << SSC_SET_RANGE_SHIFT)
+#define SSC_SET_RANGE_4003 (0x2 << SSC_SET_RANGE_SHIFT)
+
+#define VBUS_EN_VBUS_EN BIT(1)
+
+struct rcar_gen3_usb3 {
+ void __iomem *base;
+ struct phy *phy;
+ u32 ssc_range;
+ bool usb3s_clk;
+ bool usb_extal;
+};
+
+static void rcar_gen3_phy_usb3_enable_ssc(struct rcar_gen3_usb3 *r)
+{
+ u16 val = SSC_SET_SSC_EN;
+
+ switch (r->ssc_range) {
+ case 4980:
+ val |= SSC_SET_RANGE_4980;
+ break;
+ case 4492:
+ val |= SSC_SET_RANGE_4492;
+ break;
+ case 4003:
+ val |= SSC_SET_RANGE_4003;
+ break;
+ default:
+ dev_err(&r->phy->dev, "%s: unsupported range (%x)\n", __func__,
+ r->ssc_range);
+ return;
+ }
+
+ writew(val, r->base + USB30_SSC_SET);
+}
+
+static void rcar_gen3_phy_usb3_select_usb_extal(struct rcar_gen3_usb3 *r)
+{
+ writew(CLKSET0_USB_EXTAL, r->base + USB30_CLKSET0);
+ writew(CLKSET1_USB_EXTAL, r->base + USB30_CLKSET1);
+}
+
+static int rcar_gen3_phy_usb3_init(struct phy *p)
+{
+ struct rcar_gen3_usb3 *r = phy_get_drvdata(p);
+
+ dev_info(&r->phy->dev, "%s: enter (%d, %d, %d)\n", __func__,
+ r->usb3s_clk, r->usb_extal, r->ssc_range);
+
+ if (!r->usb3s_clk && r->usb_extal) {
+ rcar_gen3_phy_usb3_select_usb_extal(r);
+ /* SSC can be enabled when usb_extal is used */
+ if (r->ssc_range)
+ rcar_gen3_phy_usb3_enable_ssc(r);
+ }
+
+ /* Enables VBUS detection anyway */
+ writew(VBUS_EN_VBUS_EN, r->base + USB30_VBUS_EN);
+
+ return 0;
+}
+
+static const struct phy_ops rcar_gen3_phy_usb3_ops = {
+ .init = rcar_gen3_phy_usb3_init,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id rcar_gen3_phy_usb3_match_table[] = {
+ { .compatible = "renesas,r8a7795-usb3-phy" },
+ { .compatible = "renesas,r8a7796-usb3-phy" },
+ { .compatible = "renesas,rcar-gen3-usb3-phy" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, rcar_gen3_phy_usb3_match_table);
+
+static int rcar_gen3_phy_usb3_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rcar_gen3_usb3 *r;
+ struct phy_provider *provider;
+ struct resource *res;
+ int ret = 0;
+ struct clk *clk;
+
+ if (!dev->of_node) {
+ dev_err(dev, "This driver needs device tree\n");
+ return -EINVAL;
+ }
+
+ r = devm_kzalloc(dev, sizeof(*r), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ r->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(r->base))
+ return PTR_ERR(r->base);
+
+ clk = devm_clk_get(dev, "usb3s_clk");
+ if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
+ r->usb3s_clk = !!clk_get_rate(clk);
+ clk_disable_unprepare(clk);
+ }
+ clk = devm_clk_get(dev, "usb_extal");
+ if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
+ r->usb_extal = !!clk_get_rate(clk);
+ clk_disable_unprepare(clk);
+ }
+
+ if (!r->usb3s_clk && !r->usb_extal) {
+ dev_err(dev, "This driver needs usb3s_clk and/or usb_extal\n");
+ ret = -EINVAL;
+ goto error;
+ }
+
+ /*
+ * devm_phy_create() will call pm_runtime_enable(&phy->dev);
+ * And then, phy-core will manage runtime pm for this device.
+ */
+ pm_runtime_enable(dev);
+
+ r->phy = devm_phy_create(dev, NULL, &rcar_gen3_phy_usb3_ops);
+ if (IS_ERR(r->phy)) {
+ dev_err(dev, "Failed to create USB3 PHY\n");
+ ret = PTR_ERR(r->phy);
+ goto error;
+ }
+
+ of_property_read_u32(dev->of_node, "renesas,ssc-range", &r->ssc_range);
+
+ platform_set_drvdata(pdev, r);
+ phy_set_drvdata(r->phy, r);
+
+ provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(provider)) {
+ dev_err(dev, "Failed to register PHY provider\n");
+ ret = PTR_ERR(provider);
+ goto error;
+ }
+
+ return 0;
+
+error:
+ pm_runtime_disable(dev);
+
+ return ret;
+}
+
+static int rcar_gen3_phy_usb3_remove(struct platform_device *pdev)
+{
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+};
+
+static struct platform_driver rcar_gen3_phy_usb3_driver = {
+ .driver = {
+ .name = "phy_rcar_gen3_usb3",
+ .of_match_table = rcar_gen3_phy_usb3_match_table,
+ },
+ .probe = rcar_gen3_phy_usb3_probe,
+ .remove = rcar_gen3_phy_usb3_remove,
+};
+module_platform_driver(rcar_gen3_phy_usb3_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Renesas R-Car Gen3 USB 3.0 PHY");
+MODULE_AUTHOR("Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>");
--
1.9.1