swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd authored by Linus Torvalds on 06 May 2019, 00:42:58 UTC
Linux 5.1
Linux 5.1
Tip revision: e93c9c9
phy-dm816x-usb.c
/*
* 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 version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; 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/regmap.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/io.h>
#include <linux/usb/phy_companion.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
#include <linux/delay.h>
#include <linux/phy/phy.h>
#include <linux/of_platform.h>
#include <linux/mfd/syscon.h>
/*
* TRM has two sets of USB_CTRL registers.. The correct register bits
* are in TRM section 24.9.8.2 USB_CTRL Register. The TRM documents the
* phy as being SR70LX Synopsys USB 2.0 OTG nanoPHY. It also seems at
* least dm816x rev c ignores writes to USB_CTRL register, but the TI
* kernel is writing to those so it's possible that later revisions
* have worknig USB_CTRL register.
*
* Also note that At least USB_CTRL register seems to be dm816x specific
* according to the TRM. It's possible that USBPHY_CTRL is more generic,
* but that would have to be checked against the SR70LX documentation
* which does not seem to be publicly available.
*
* Finally, the phy on dm814x and am335x is different from dm816x.
*/
#define DM816X_USB_CTRL_PHYCLKSRC BIT(8) /* 1 = PLL ref clock */
#define DM816X_USB_CTRL_PHYSLEEP1 BIT(1) /* Enable the first phy */
#define DM816X_USB_CTRL_PHYSLEEP0 BIT(0) /* Enable the second phy */
#define DM816X_USBPHY_CTRL_TXRISETUNE 1
#define DM816X_USBPHY_CTRL_TXVREFTUNE 0xc
#define DM816X_USBPHY_CTRL_TXPREEMTUNE 0x2
struct dm816x_usb_phy {
struct regmap *syscon;
struct device *dev;
unsigned int instance;
struct clk *refclk;
struct usb_phy phy;
unsigned int usb_ctrl; /* Shared between phy0 and phy1 */
unsigned int usbphy_ctrl;
};
static int dm816x_usb_phy_set_host(struct usb_otg *otg, struct usb_bus *host)
{
otg->host = host;
if (!host)
otg->state = OTG_STATE_UNDEFINED;
return 0;
}
static int dm816x_usb_phy_set_peripheral(struct usb_otg *otg,
struct usb_gadget *gadget)
{
otg->gadget = gadget;
if (!gadget)
otg->state = OTG_STATE_UNDEFINED;
return 0;
}
static int dm816x_usb_phy_init(struct phy *x)
{
struct dm816x_usb_phy *phy = phy_get_drvdata(x);
unsigned int val;
int error;
if (clk_get_rate(phy->refclk) != 24000000)
dev_warn(phy->dev, "nonstandard phy refclk\n");
/* Set PLL ref clock and put phys to sleep */
error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
DM816X_USB_CTRL_PHYCLKSRC |
DM816X_USB_CTRL_PHYSLEEP1 |
DM816X_USB_CTRL_PHYSLEEP0,
0);
regmap_read(phy->syscon, phy->usb_ctrl, &val);
if ((val & 3) != 0)
dev_info(phy->dev,
"Working dm816x USB_CTRL! (0x%08x)\n",
val);
/*
* TI kernel sets these values for "symmetrical eye diagram and
* better signal quality" so let's assume somebody checked the
* values with a scope and set them here too.
*/
regmap_read(phy->syscon, phy->usbphy_ctrl, &val);
val |= DM816X_USBPHY_CTRL_TXRISETUNE |
DM816X_USBPHY_CTRL_TXVREFTUNE |
DM816X_USBPHY_CTRL_TXPREEMTUNE;
regmap_write(phy->syscon, phy->usbphy_ctrl, val);
return 0;
}
static const struct phy_ops ops = {
.init = dm816x_usb_phy_init,
.owner = THIS_MODULE,
};
static int __maybe_unused dm816x_usb_phy_runtime_suspend(struct device *dev)
{
struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
unsigned int mask, val;
int error = 0;
mask = BIT(phy->instance);
val = ~BIT(phy->instance);
error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
mask, val);
if (error)
dev_err(phy->dev, "phy%i failed to power off\n",
phy->instance);
clk_disable(phy->refclk);
return 0;
}
static int __maybe_unused dm816x_usb_phy_runtime_resume(struct device *dev)
{
struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
unsigned int mask, val;
int error;
error = clk_enable(phy->refclk);
if (error)
return error;
/*
* Note that at least dm816x rev c does not seem to do
* anything with the USB_CTRL register. But let's follow
* what the TI tree is doing in case later revisions use
* USB_CTRL.
*/
mask = BIT(phy->instance);
val = BIT(phy->instance);
error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
mask, val);
if (error) {
dev_err(phy->dev, "phy%i failed to power on\n",
phy->instance);
clk_disable(phy->refclk);
return error;
}
return 0;
}
static UNIVERSAL_DEV_PM_OPS(dm816x_usb_phy_pm_ops,
dm816x_usb_phy_runtime_suspend,
dm816x_usb_phy_runtime_resume,
NULL);
#ifdef CONFIG_OF
static const struct of_device_id dm816x_usb_phy_id_table[] = {
{
.compatible = "ti,dm8168-usb-phy",
},
{},
};
MODULE_DEVICE_TABLE(of, dm816x_usb_phy_id_table);
#endif
static int dm816x_usb_phy_probe(struct platform_device *pdev)
{
struct dm816x_usb_phy *phy;
struct resource *res;
struct phy *generic_phy;
struct phy_provider *phy_provider;
struct usb_otg *otg;
const struct of_device_id *of_id;
const struct usb_phy_data *phy_data;
int error;
of_id = of_match_device(of_match_ptr(dm816x_usb_phy_id_table),
&pdev->dev);
if (!of_id)
return -EINVAL;
phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
if (!phy)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENOENT;
phy->syscon = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"syscon");
if (IS_ERR(phy->syscon))
return PTR_ERR(phy->syscon);
/*
* According to sprs614e.pdf, the first usb_ctrl is shared and
* the second instance for usb_ctrl is reserved.. Also the
* register bits are different from earlier TRMs.
*/
phy->usb_ctrl = 0x20;
phy->usbphy_ctrl = (res->start & 0xff) + 4;
if (phy->usbphy_ctrl == 0x2c)
phy->instance = 1;
phy_data = of_id->data;
otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
if (!otg)
return -ENOMEM;
phy->dev = &pdev->dev;
phy->phy.dev = phy->dev;
phy->phy.label = "dm8168_usb_phy";
phy->phy.otg = otg;
phy->phy.type = USB_PHY_TYPE_USB2;
otg->set_host = dm816x_usb_phy_set_host;
otg->set_peripheral = dm816x_usb_phy_set_peripheral;
otg->usb_phy = &phy->phy;
platform_set_drvdata(pdev, phy);
phy->refclk = devm_clk_get(phy->dev, "refclk");
if (IS_ERR(phy->refclk))
return PTR_ERR(phy->refclk);
error = clk_prepare(phy->refclk);
if (error)
return error;
pm_runtime_enable(phy->dev);
generic_phy = devm_phy_create(phy->dev, NULL, &ops);
if (IS_ERR(generic_phy))
return PTR_ERR(generic_phy);
phy_set_drvdata(generic_phy, phy);
phy_provider = devm_of_phy_provider_register(phy->dev,
of_phy_simple_xlate);
if (IS_ERR(phy_provider))
return PTR_ERR(phy_provider);
usb_add_phy_dev(&phy->phy);
return 0;
}
static int dm816x_usb_phy_remove(struct platform_device *pdev)
{
struct dm816x_usb_phy *phy = platform_get_drvdata(pdev);
usb_remove_phy(&phy->phy);
pm_runtime_disable(phy->dev);
clk_unprepare(phy->refclk);
return 0;
}
static struct platform_driver dm816x_usb_phy_driver = {
.probe = dm816x_usb_phy_probe,
.remove = dm816x_usb_phy_remove,
.driver = {
.name = "dm816x-usb-phy",
.pm = &dm816x_usb_phy_pm_ops,
.of_match_table = of_match_ptr(dm816x_usb_phy_id_table),
},
};
module_platform_driver(dm816x_usb_phy_driver);
MODULE_ALIAS("platform:dm816x_usb");
MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
MODULE_DESCRIPTION("dm816x usb phy driver");
MODULE_LICENSE("GPL v2");