mirror of
https://github.com/torvalds/linux.git
synced 2024-11-29 23:51:37 +00:00
d3feb40673
Northstar is a family of SoCs used in home routers. They have USB 2.0 and 3.0 controllers with PHYs that need to be properly initialized. This driver provides PHY init support in a generic way and can be bound with an EHCI controller driver. There are (just a few) registers being defined in bcma header. It's because DMU/CRU registers will be also needed in other drivers. We will need them e.g. in PCIe controller/PHY driver and at some point probably in clock driver for BCM53573 chipset. By using include/linux/bcma/ we avoid code duplication. Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
138 lines
3.5 KiB
C
138 lines
3.5 KiB
C
/*
|
|
* Broadcom Northstar USB 2.0 PHY Driver
|
|
*
|
|
* Copyright (C) 2016 Rafał Miłecki <zajec5@gmail.com>
|
|
*
|
|
* 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/bcma/bcma.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/err.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_platform.h>
|
|
#include <linux/phy/phy.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
|
|
struct bcm_ns_usb2 {
|
|
struct device *dev;
|
|
struct clk *ref_clk;
|
|
struct phy *phy;
|
|
void __iomem *dmu;
|
|
};
|
|
|
|
static int bcm_ns_usb2_phy_init(struct phy *phy)
|
|
{
|
|
struct bcm_ns_usb2 *usb2 = phy_get_drvdata(phy);
|
|
struct device *dev = usb2->dev;
|
|
void __iomem *dmu = usb2->dmu;
|
|
u32 ref_clk_rate, usb2ctl, usb_pll_ndiv, usb_pll_pdiv;
|
|
int err = 0;
|
|
|
|
err = clk_prepare_enable(usb2->ref_clk);
|
|
if (err < 0) {
|
|
dev_err(dev, "Failed to prepare ref clock: %d\n", err);
|
|
goto err_out;
|
|
}
|
|
|
|
ref_clk_rate = clk_get_rate(usb2->ref_clk);
|
|
if (!ref_clk_rate) {
|
|
dev_err(dev, "Failed to get ref clock rate\n");
|
|
err = -EINVAL;
|
|
goto err_clk_off;
|
|
}
|
|
|
|
usb2ctl = readl(dmu + BCMA_DMU_CRU_USB2_CONTROL);
|
|
|
|
if (usb2ctl & BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK) {
|
|
usb_pll_pdiv = usb2ctl;
|
|
usb_pll_pdiv &= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK;
|
|
usb_pll_pdiv >>= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT;
|
|
} else {
|
|
usb_pll_pdiv = 1 << 3;
|
|
}
|
|
|
|
/* Calculate ndiv based on a solid 1920 MHz that is for USB2 PHY */
|
|
usb_pll_ndiv = (1920000000 * usb_pll_pdiv) / ref_clk_rate;
|
|
|
|
/* Unlock DMU PLL settings with some magic value */
|
|
writel(0x0000ea68, dmu + BCMA_DMU_CRU_CLKSET_KEY);
|
|
|
|
/* Write USB 2.0 PLL control setting */
|
|
usb2ctl &= ~BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK;
|
|
usb2ctl |= usb_pll_ndiv << BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT;
|
|
writel(usb2ctl, dmu + BCMA_DMU_CRU_USB2_CONTROL);
|
|
|
|
/* Lock DMU PLL settings */
|
|
writel(0x00000000, dmu + BCMA_DMU_CRU_CLKSET_KEY);
|
|
|
|
err_clk_off:
|
|
clk_disable_unprepare(usb2->ref_clk);
|
|
err_out:
|
|
return err;
|
|
}
|
|
|
|
static const struct phy_ops ops = {
|
|
.init = bcm_ns_usb2_phy_init,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int bcm_ns_usb2_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct bcm_ns_usb2 *usb2;
|
|
struct resource *res;
|
|
struct phy_provider *phy_provider;
|
|
|
|
usb2 = devm_kzalloc(&pdev->dev, sizeof(*usb2), GFP_KERNEL);
|
|
if (!usb2)
|
|
return -ENOMEM;
|
|
usb2->dev = dev;
|
|
|
|
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dmu");
|
|
usb2->dmu = devm_ioremap_resource(dev, res);
|
|
if (IS_ERR(usb2->dmu)) {
|
|
dev_err(dev, "Failed to map DMU regs\n");
|
|
return PTR_ERR(usb2->dmu);
|
|
}
|
|
|
|
usb2->ref_clk = devm_clk_get(dev, "phy-ref-clk");
|
|
if (IS_ERR(usb2->ref_clk)) {
|
|
dev_err(dev, "Clock not defined\n");
|
|
return PTR_ERR(usb2->ref_clk);
|
|
}
|
|
|
|
usb2->phy = devm_phy_create(dev, NULL, &ops);
|
|
if (IS_ERR(dev))
|
|
return PTR_ERR(dev);
|
|
|
|
phy_set_drvdata(usb2->phy, usb2);
|
|
platform_set_drvdata(pdev, usb2);
|
|
|
|
phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
|
|
return PTR_ERR_OR_ZERO(phy_provider);
|
|
}
|
|
|
|
static const struct of_device_id bcm_ns_usb2_id_table[] = {
|
|
{ .compatible = "brcm,ns-usb2-phy", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, bcm_ns_usb2_id_table);
|
|
|
|
static struct platform_driver bcm_ns_usb2_driver = {
|
|
.probe = bcm_ns_usb2_probe,
|
|
.driver = {
|
|
.name = "bcm_ns_usb2",
|
|
.of_match_table = bcm_ns_usb2_id_table,
|
|
},
|
|
};
|
|
module_platform_driver(bcm_ns_usb2_driver);
|
|
|
|
MODULE_LICENSE("GPL v2");
|