Commit 387c359b authored by Roger Quadros's avatar Roger Quadros Committed by Felipe Balbi
Browse files

usb: cdns3: Add TI specific wrapper driver 



The J721e platform comes with 2 Cadence USB3 controller
instances. This driver supports the TI specific wrapper
on this platform.

Signed-off-by: default avatarRoger Quadros <rogerq@ti.com>
Signed-off-by: default avatarSekhar Nori <nsekhar@ti.com>
Reviewed-by: default avatarPawel Laszczak <pawell@cadence.com>
Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
parent 4c48f236

drivers/usb/cdns3/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -43,4 +43,14 @@ config USB_CDNS3_PCI_WRAP 
	  If you choose to build this driver as module it will

	  be dynamically linked and module will be called cdns3-pci.ko



config USB_CDNS3_TI

	tristate "Cadence USB3 support on TI platforms"

	depends on ARCH_K3 || COMPILE_TEST

	default USB_CDNS3

	help

	  Say 'Y' or 'M' here if you are building for Texas Instruments

	  platforms that contain Cadence USB3 controller core.



	  e.g. J721e.



endif

drivers/usb/cdns3/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -14,3 +14,4 @@ endif 
cdns3-$(CONFIG_USB_CDNS3_HOST)		+= host.o



obj-$(CONFIG_USB_CDNS3_PCI_WRAP)	+= cdns3-pci-wrap.o

obj-$(CONFIG_USB_CDNS3_TI)		+= cdns3-ti.o

drivers/usb/cdns3/cdns3-ti.c

0 → 100644
+236 −0
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// SPDX-License-Identifier: GPL-2.0

/**

 * cdns3-ti.c - TI specific Glue layer for Cadence USB Controller

 *

 * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com

 */



#include <linux/bits.h>

#include <linux/clk.h>

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

#include <linux/dma-mapping.h>

#include <linux/io.h>

#include <linux/of_platform.h>

#include <linux/pm_runtime.h>



/* USB Wrapper register offsets */

#define USBSS_PID		0x0

#define	USBSS_W1		0x4

#define USBSS_STATIC_CONFIG	0x8

#define USBSS_PHY_TEST		0xc

#define	USBSS_DEBUG_CTRL	0x10

#define	USBSS_DEBUG_INFO	0x14

#define	USBSS_DEBUG_LINK_STATE	0x18

#define	USBSS_DEVICE_CTRL	0x1c



/* Wrapper 1 register bits */

#define USBSS_W1_PWRUP_RST		BIT(0)

#define USBSS_W1_OVERCURRENT_SEL	BIT(8)

#define USBSS_W1_MODESTRAP_SEL		BIT(9)

#define USBSS_W1_OVERCURRENT		BIT(16)

#define USBSS_W1_MODESTRAP_MASK		GENMASK(18, 17)

#define USBSS_W1_MODESTRAP_SHIFT	17

#define USBSS_W1_USB2_ONLY		BIT(19)



/* Static config register bits */

#define USBSS1_STATIC_PLL_REF_SEL_MASK	GENMASK(8, 5)

#define USBSS1_STATIC_PLL_REF_SEL_SHIFT	5

#define USBSS1_STATIC_LOOPBACK_MODE_MASK	GENMASK(4, 3)

#define USBSS1_STATIC_LOOPBACK_MODE_SHIFT	3

#define USBSS1_STATIC_VBUS_SEL_MASK	GENMASK(2, 1)

#define USBSS1_STATIC_VBUS_SEL_SHIFT	1

#define USBSS1_STATIC_LANE_REVERSE	BIT(0)



/* Modestrap modes */

enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE,

		      USBSS_MODESTRAP_MODE_HOST,

		      USBSS_MODESTRAP_MODE_PERIPHERAL};



struct cdns_ti {

	struct device *dev;

	void __iomem *usbss;

	int usb2_only:1;

	int vbus_divider:1;

	struct clk *usb2_refclk;

	struct clk *lpm_clk;

};



static const int cdns_ti_rate_table[] = {	/* in KHZ */

	9600,

	10000,

	12000,

	19200,

	20000,

	24000,

	25000,

	26000,

	38400,

	40000,

	58000,

	50000,

	52000,

};



static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset)

{

	return readl(data->usbss + offset);

}



static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value)

{

	writel(value, data->usbss + offset);

}



static int cdns_ti_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct device_node *node = pdev->dev.of_node;

	struct cdns_ti *data;

	int error;

	u32 reg;

	int rate_code, i;

	unsigned long rate;



	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);

	if (!data)

		return -ENOMEM;



	platform_set_drvdata(pdev, data);



	data->dev = dev;



	data->usbss = devm_platform_ioremap_resource(pdev, 0);

	if (IS_ERR(data->usbss)) {

		dev_err(dev, "can't map IOMEM resource\n");

		return PTR_ERR(data->usbss);

	}



	data->usb2_refclk = devm_clk_get(dev, "ref");

	if (IS_ERR(data->usb2_refclk)) {

		dev_err(dev, "can't get usb2_refclk\n");

		return PTR_ERR(data->usb2_refclk);

	}



	data->lpm_clk = devm_clk_get(dev, "lpm");

	if (IS_ERR(data->lpm_clk)) {

		dev_err(dev, "can't get lpm_clk\n");

		return PTR_ERR(data->lpm_clk);

	}



	rate = clk_get_rate(data->usb2_refclk);

	rate /= 1000;	/* To KHz */

	for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) {

		if (cdns_ti_rate_table[i] == rate)

			break;

	}



	if (i == ARRAY_SIZE(cdns_ti_rate_table)) {

		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);

		return -EINVAL;

	}



	rate_code = i;



	pm_runtime_enable(dev);

	error = pm_runtime_get_sync(dev);

	if (error < 0) {

		dev_err(dev, "pm_runtime_get_sync failed: %d\n", error);

		goto err_get;

	}



	/* assert RESET */

	reg = cdns_ti_readl(data, USBSS_W1);

	reg &= ~USBSS_W1_PWRUP_RST;

	cdns_ti_writel(data, USBSS_W1, reg);



	/* set static config */

	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);

	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;

	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;



	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;

	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");

	if (data->vbus_divider)

		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;



	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);

	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);



	/* set USB2_ONLY mode if requested */

	reg = cdns_ti_readl(data, USBSS_W1);

	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");

	if (data->usb2_only)

		reg |= USBSS_W1_USB2_ONLY;



	/* set default modestrap */

	reg |= USBSS_W1_MODESTRAP_SEL;

	reg &= ~USBSS_W1_MODESTRAP_MASK;

	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;

	cdns_ti_writel(data, USBSS_W1, reg);



	/* de-assert RESET */

	reg |= USBSS_W1_PWRUP_RST;

	cdns_ti_writel(data, USBSS_W1, reg);



	error = of_platform_populate(node, NULL, NULL, dev);

	if (error) {

		dev_err(dev, "failed to create children: %d\n", error);

		goto err;

	}



	return 0;



err:

	pm_runtime_put_sync(data->dev);

err_get:

	pm_runtime_disable(data->dev);



	return error;

}



static int cdns_ti_remove_core(struct device *dev, void *c)

{

	struct platform_device *pdev = to_platform_device(dev);



	platform_device_unregister(pdev);



	return 0;

}



static int cdns_ti_remove(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;



	device_for_each_child(dev, NULL, cdns_ti_remove_core);

	pm_runtime_put_sync(dev);

	pm_runtime_disable(dev);



	platform_set_drvdata(pdev, NULL);



	return 0;

}



static const struct of_device_id cdns_ti_of_match[] = {

	{ .compatible = "ti,j721e-usb", },

	{},

};

MODULE_DEVICE_TABLE(of, cdns_ti_of_match);



static struct platform_driver cdns_ti_driver = {

	.probe		= cdns_ti_probe,

	.remove		= cdns_ti_remove,

	.driver		= {

		.name	= "cdns3-ti",

		.of_match_table	= cdns_ti_of_match,

	},

};



module_platform_driver(cdns_ti_driver);



MODULE_ALIAS("platform:cdns3-ti");

MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer");