[PATCH v8 1/2] usb: phy: samsung: Introducing usb phy driver for hsotg
Praveen Paneri
p.paneri at samsung.com
Wed Nov 14 05:27:15 EST 2012
This driver uses usb_phy interface to interact with s3c-hsotg. Supports
phy_init and phy_shutdown functions to enable/disable usb phy. Support
will be extended to host controllers and more Samsung SoCs.
Signed-off-by: Praveen Paneri <p.paneri at samsung.com>
Acked-by: Heiko Stuebner <heiko at sntech.de>
Acked-by: Kyungmin Park <kyungmin.park at samsung.com>
---
.../devicetree/bindings/usb/samsung-usbphy.txt | 11 +
drivers/usb/phy/Kconfig | 8 +
drivers/usb/phy/Makefile | 1 +
drivers/usb/phy/samsung-usbphy.c | 360 ++++++++++++++++++++
include/linux/platform_data/samsung-usbphy.h | 27 ++
5 files changed, 407 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/usb/samsung-usbphy.txt
create mode 100644 drivers/usb/phy/samsung-usbphy.c
create mode 100644 include/linux/platform_data/samsung-usbphy.h
diff --git a/Documentation/devicetree/bindings/usb/samsung-usbphy.txt b/Documentation/devicetree/bindings/usb/samsung-usbphy.txt
new file mode 100644
index 0000000..7b26e2d
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/samsung-usbphy.txt
@@ -0,0 +1,11 @@
+* Samsung's usb phy transceiver
+
+The Samsung's phy transceiver is used for controlling usb otg phy for
+s3c-hsotg usb device controller.
+TODO: Adding the PHY binding with controller(s) according to the under
+developement generic PHY driver.
+
+Required properties:
+- compatible : should be "samsung,exynos4210-usbphy"
+- reg : base physical address of the phy registers and length of memory mapped
+ region.
diff --git a/drivers/usb/phy/Kconfig b/drivers/usb/phy/Kconfig
index 7eb73c5..17ad743 100644
--- a/drivers/usb/phy/Kconfig
+++ b/drivers/usb/phy/Kconfig
@@ -44,3 +44,11 @@ config USB_RCAR_PHY
To compile this driver as a module, choose M here: the
module will be called rcar-phy.
+
+config SAMSUNG_USBPHY
+ bool "Samsung USB PHY controller Driver"
+ depends on USB_S3C_HSOTG
+ select USB_OTG_UTILS
+ help
+ Enable this to support Samsung USB phy controller for samsung
+ SoCs.
diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
index 1a579a8..ec304f6 100644
--- a/drivers/usb/phy/Makefile
+++ b/drivers/usb/phy/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_USB_ISP1301) += isp1301.o
obj-$(CONFIG_MV_U3D_PHY) += mv_u3d_phy.o
obj-$(CONFIG_USB_EHCI_TEGRA) += tegra_usb_phy.o
obj-$(CONFIG_USB_RCAR_PHY) += rcar-phy.o
+obj-$(CONFIG_SAMSUNG_USBPHY) += samsung-usbphy.o
diff --git a/drivers/usb/phy/samsung-usbphy.c b/drivers/usb/phy/samsung-usbphy.c
new file mode 100644
index 0000000..3c84aab
--- /dev/null
+++ b/drivers/usb/phy/samsung-usbphy.c
@@ -0,0 +1,360 @@
+/* linux/drivers/usb/phy/samsung-usbphy.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Author: Praveen Paneri <p.paneri at samsung.com>
+ *
+ * Samsung USB2.0 High-speed OTG transceiver, talks to S3C HS OTG controller
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/usb/otg.h>
+#include <linux/platform_data/samsung-usbphy.h>
+
+/* Register definitions */
+
+#define SAMSUNG_PHYPWR (0x00)
+
+#define PHYPWR_NORMAL_MASK (0x19 << 0)
+#define PHYPWR_OTG_DISABLE (0x1 << 4)
+#define PHYPWR_ANALOG_POWERDOWN (0x1 << 3)
+#define PHYPWR_FORCE_SUSPEND (0x1 << 1)
+/* For Exynos4 */
+#define PHYPWR_NORMAL_MASK_PHY0 (0x39 << 0)
+#define PHYPWR_SLEEP_PHY0 (0x1 << 5)
+
+#define SAMSUNG_PHYCLK (0x04)
+
+#define PHYCLK_MODE_USB11 (0x1 << 6)
+#define PHYCLK_EXT_OSC (0x1 << 5)
+#define PHYCLK_COMMON_ON_N (0x1 << 4)
+#define PHYCLK_ID_PULL (0x1 << 2)
+#define PHYCLK_CLKSEL_MASK (0x3 << 0)
+#define PHYCLK_CLKSEL_48M (0x0 << 0)
+#define PHYCLK_CLKSEL_12M (0x2 << 0)
+#define PHYCLK_CLKSEL_24M (0x3 << 0)
+
+#define SAMSUNG_RSTCON (0x08)
+
+#define RSTCON_PHYLINK_SWRST (0x1 << 2)
+#define RSTCON_HLINK_SWRST (0x1 << 1)
+#define RSTCON_SWRST (0x1 << 0)
+
+#ifndef MHZ
+#define MHZ (1000*1000)
+#endif
+
+enum samsung_cpu_type {
+ TYPE_S3C64XX,
+ TYPE_EXYNOS4210,
+};
+
+/*
+ * struct samsung_usbphy - transceiver driver state
+ * @phy: transceiver structure
+ * @plat: platform data
+ * @dev: The parent device supplied to the probe function
+ * @clk: usb phy clock
+ * @regs: usb phy register memory base
+ * @ref_clk_freq: reference clock frequency selection
+ * @cpu_type: machine identifier
+ */
+struct samsung_usbphy {
+ struct usb_phy phy;
+ struct samsung_usbphy_data *plat;
+ struct device *dev;
+ struct clk *clk;
+ void __iomem *regs;
+ int ref_clk_freq;
+ int cpu_type;
+};
+
+#define phy_to_sphy(x) container_of((x), struct samsung_usbphy, phy)
+
+/*
+ * Returns reference clock frequency selection value
+ */
+static int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
+{
+ struct clk *ref_clk;
+ int refclk_freq = 0;
+
+ ref_clk = clk_get(sphy->dev, "xusbxti");
+ if (IS_ERR(ref_clk)) {
+ dev_err(sphy->dev, "Failed to get reference clock\n");
+ return PTR_ERR(ref_clk);
+ }
+
+ switch (clk_get_rate(ref_clk)) {
+ case 12 * MHZ:
+ refclk_freq = PHYCLK_CLKSEL_12M;
+ break;
+ case 24 * MHZ:
+ refclk_freq = PHYCLK_CLKSEL_24M;
+ break;
+ case 48 * MHZ:
+ refclk_freq = PHYCLK_CLKSEL_48M;
+ break;
+ default:
+ if (sphy->cpu_type == TYPE_S3C64XX)
+ refclk_freq = PHYCLK_CLKSEL_48M;
+ else
+ refclk_freq = PHYCLK_CLKSEL_24M;
+ break;
+ }
+ clk_put(ref_clk);
+
+ return refclk_freq;
+}
+
+static void samsung_usbphy_enable(struct samsung_usbphy *sphy)
+{
+ void __iomem *regs = sphy->regs;
+ u32 phypwr;
+ u32 phyclk;
+ u32 rstcon;
+
+ /* set clock frequency for PLL */
+ phyclk = sphy->ref_clk_freq;
+ phypwr = readl(regs + SAMSUNG_PHYPWR);
+ rstcon = readl(regs + SAMSUNG_RSTCON);
+
+ switch (sphy->cpu_type) {
+ case TYPE_S3C64XX:
+ phyclk &= ~PHYCLK_COMMON_ON_N;
+ phypwr &= ~PHYPWR_NORMAL_MASK;
+ rstcon |= RSTCON_SWRST;
+ break;
+ case TYPE_EXYNOS4210:
+ phypwr &= ~PHYPWR_NORMAL_MASK_PHY0;
+ rstcon |= RSTCON_SWRST;
+ default:
+ break;
+ }
+
+ writel(phyclk, regs + SAMSUNG_PHYCLK);
+ /* set to normal of PHY0 */
+ writel(phypwr, regs + SAMSUNG_PHYPWR);
+ /* reset all ports of PHY and Link */
+ writel(rstcon, regs + SAMSUNG_RSTCON);
+ udelay(10);
+ rstcon &= ~RSTCON_SWRST;
+ writel(rstcon, regs + SAMSUNG_RSTCON);
+}
+
+static void samsung_usbphy_disable(struct samsung_usbphy *sphy)
+{
+ void __iomem *regs = sphy->regs;
+ u32 phypwr;
+
+ phypwr = readl(regs + SAMSUNG_PHYPWR);
+
+ switch (sphy->cpu_type) {
+ case TYPE_S3C64XX:
+ phypwr |= PHYPWR_NORMAL_MASK;
+ break;
+ case TYPE_EXYNOS4210:
+ phypwr |= PHYPWR_NORMAL_MASK_PHY0;
+ default:
+ break;
+ }
+
+ /* unset to normal of PHY0 */
+ writel(phypwr, regs + SAMSUNG_PHYPWR);
+}
+
+/*
+ * The function passed to the usb driver for phy initialization
+ */
+static int samsung_usbphy_init(struct usb_phy *phy)
+{
+ struct samsung_usbphy *sphy;
+ int ret = 0;
+
+ sphy = phy_to_sphy(phy);
+
+ /* Enable the phy clock */
+ ret = clk_prepare_enable(sphy->clk);
+ if (ret) {
+ dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
+ return ret;
+ }
+
+ /* Disable phy isolation */
+ if (sphy->plat && sphy->plat->pmu_isolation)
+ sphy->plat->pmu_isolation(false);
+
+ /* Initialize usb phy registers */
+ samsung_usbphy_enable(sphy);
+
+ /* Disable the phy clock */
+ clk_disable_unprepare(sphy->clk);
+ return ret;
+}
+
+/*
+ * The function passed to the usb driver for phy shutdown
+ */
+static void samsung_usbphy_shutdown(struct usb_phy *phy)
+{
+ struct samsung_usbphy *sphy;
+
+ sphy = phy_to_sphy(phy);
+
+ if (clk_prepare_enable(sphy->clk)) {
+ dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
+ return;
+ }
+
+ /* De-initialize usb phy registers */
+ samsung_usbphy_disable(sphy);
+
+ /* Enable phy isolation */
+ if (sphy->plat && sphy->plat->pmu_isolation)
+ sphy->plat->pmu_isolation(true);
+
+ clk_disable_unprepare(sphy->clk);
+}
+
+static const struct of_device_id samsung_usbphy_dt_match[];
+
+static inline int samsung_usbphy_get_driver_data(struct platform_device *pdev)
+{
+ if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
+ int data;
+ const struct of_device_id *match;
+ match = of_match_node(samsung_usbphy_dt_match,
+ pdev->dev.of_node);
+ data = (int) match->data;
+ return data;
+ }
+
+ return platform_get_device_id(pdev)->driver_data;
+}
+
+static int __devinit samsung_usbphy_probe(struct platform_device *pdev)
+{
+ struct samsung_usbphy *sphy;
+ struct samsung_usbphy_data *pdata;
+ struct device *dev = &pdev->dev;
+ struct resource *phy_mem;
+ void __iomem *phy_base;
+ struct clk *clk;
+ int ret = 0;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata) {
+ dev_err(&pdev->dev, "%s: no platform data defined\n", __func__);
+ return -EINVAL;
+ }
+
+ phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!phy_mem) {
+ dev_err(dev, "%s: missing mem resource\n", __func__);
+ return -ENODEV;
+ }
+
+ phy_base = devm_request_and_ioremap(dev, phy_mem);
+ if (!phy_base) {
+ dev_err(dev, "%s: register mapping failed\n", __func__);
+ return -ENXIO;
+ }
+
+ sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
+ if (!sphy)
+ return -ENOMEM;
+
+ clk = devm_clk_get(dev, "otg");
+ if (IS_ERR(clk)) {
+ dev_err(dev, "Failed to get otg clock\n");
+ return PTR_ERR(clk);
+ }
+
+ sphy->dev = &pdev->dev;
+ sphy->plat = pdata;
+ sphy->regs = phy_base;
+ sphy->clk = clk;
+ sphy->phy.dev = sphy->dev;
+ sphy->phy.label = "samsung-usbphy";
+ sphy->phy.init = samsung_usbphy_init;
+ sphy->phy.shutdown = samsung_usbphy_shutdown;
+ sphy->cpu_type = samsung_usbphy_get_driver_data(pdev);
+ sphy->ref_clk_freq = samsung_usbphy_get_refclk_freq(sphy);
+
+ platform_set_drvdata(pdev, sphy);
+
+ ret = usb_add_phy(&sphy->phy, USB_PHY_TYPE_USB2);
+ return ret;
+}
+
+static int __exit samsung_usbphy_remove(struct platform_device *pdev)
+{
+ struct samsung_usbphy *sphy = platform_get_drvdata(pdev);
+
+ usb_remove_phy(&sphy->phy);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id samsung_usbphy_dt_match[] = {
+ {
+ .compatible = "samsung,s3c64xx-usbphy",
+ .data = (void *)TYPE_S3C64XX,
+ }, {
+ .compatible = "samsung,exynos4210-usbphy",
+ .data = (void *)TYPE_EXYNOS4210,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
+#else
+#define samsung_usbphy_dt_match NULL
+#endif
+
+static struct platform_device_id samsung_usbphy_driver_ids[] = {
+ {
+ .name = "s3c64xx-usbphy",
+ .driver_data = TYPE_S3C64XX,
+ }, {
+ .name = "exynos4210-usbphy",
+ .driver_data = TYPE_EXYNOS4210,
+ },
+ {},
+};
+
+MODULE_DEVICE_TABLE(platform, samsung_usbphy_driver_ids);
+
+static struct platform_driver samsung_usbphy_driver = {
+ .probe = samsung_usbphy_probe,
+ .remove = __devexit_p(samsung_usbphy_remove),
+ .id_table = samsung_usbphy_driver_ids,
+ .driver = {
+ .name = "samsung-usbphy",
+ .owner = THIS_MODULE,
+ .of_match_table = samsung_usbphy_dt_match,
+ },
+};
+
+module_platform_driver(samsung_usbphy_driver);
+
+MODULE_DESCRIPTION("Samsung USB phy controller");
+MODULE_AUTHOR("Praveen Paneri <p.paneri at samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:samsung-usbphy");
diff --git a/include/linux/platform_data/samsung-usbphy.h b/include/linux/platform_data/samsung-usbphy.h
new file mode 100644
index 0000000..1bd24cb
--- /dev/null
+++ b/include/linux/platform_data/samsung-usbphy.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics Co.Ltd
+ * http://www.samsung.com/
+ * Author: Praveen Paneri <p.paneri at samsung.com>
+ *
+ * Defines platform data for samsung usb phy driver.
+ *
+ * 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.
+ */
+
+#ifndef __SAMSUNG_USBPHY_PLATFORM_H
+#define __SAMSUNG_USBPHY_PLATFORM_H
+
+/**
+ * samsung_usbphy_data - Platform data for USB PHY driver.
+ * @pmu_isolation: Function to control usb phy isolation in PMU.
+ */
+struct samsung_usbphy_data {
+ void (*pmu_isolation)(int on);
+};
+
+extern void samsung_usbphy_set_pdata(struct samsung_usbphy_data *pd);
+
+#endif /* __SAMSUNG_USBPHY_PLATFORM_H */
--
1.7.1
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