Subject: [PATCH v7 2/5] phy: add a driver for the Rockchip SoC internal USB2.0 PHY

From: [email-masked] (Yunzhi Li)
Date: Wed, 21 Jan 2015 18:06:29 +0800

Hi Kishon :
> Hi,
>
> On Friday 12 December 2014 08:37 PM, Yunzhi Li wrote:
>> This patch to add a generic PHY driver for ROCKCHIP usb PHYs,
>> currently this driver can support RK3288. The RK3288 SoC have
>> three independent USB PHY IPs which are all configured through a
>> set of registers located in the GRF (general register files)
>> module.
>>
>> Signed-off-by: Yunzhi Li <[email-masked]>
>>
>> ---
>>
>> Changes in v7:
>> - Accept Kishon's comments to use phandle args to find a phy
>>    struct directly and get rid of using a custom of_xlate
>>    function.
>>
>> Changes in v6:
>> - Rename SIDDQ_MSK to SIDDQ_WRITE_ENA.
>>
>> Changes in v5: None
>> Changes in v4:
>> - Get number of PHYs from device tree.
>> - Model each PHY as subnode of the phy provider node.
>>
>> Changes in v3:
>> - Use BIT macro instead of bit shift ops.
>> - Rename the config entry to PHY_ROCKCHIP_USB.
>>
>>   drivers/phy/Kconfig            |   7 ++
>>   drivers/phy/Makefile           |   1 +
>>   drivers/phy/phy-rockchip-usb.c | 158 +++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 166 insertions(+)
>>   create mode 100644 drivers/phy/phy-rockchip-usb.c
>>
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index ccad880..b24500a 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -239,6 +239,13 @@ config PHY_QCOM_IPQ806X_SATA
>>   	depends on OF
>>   	select GENERIC_PHY
>>   
>> +config PHY_ROCKCHIP_USB
>> +	tristate "Rockchip USB2 PHY Driver"
>> +	depends on ARCH_ROCKCHIP && OF
>> +	select GENERIC_PHY
>> +	help
>> +	  Enable this to support the Rockchip USB 2.0 PHY.
>> +
>>   config PHY_ST_SPEAR1310_MIPHY
>>   	tristate "ST SPEAR1310-MIPHY driver"
>>   	select GENERIC_PHY
>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>> index aa74f96..48bf5a1 100644
>> --- a/drivers/phy/Makefile
>> +++ b/drivers/phy/Makefile
>> @@ -28,6 +28,7 @@ phy-exynos-usb2-$(CONFIG_PHY_EXYNOS5250_USB2)	+= phy-exynos5250-usb2.o
>>   phy-exynos-usb2-$(CONFIG_PHY_S5PV210_USB2)	+= phy-s5pv210-usb2.o
>>   obj-$(CONFIG_PHY_EXYNOS5_USBDRD)	+= phy-exynos5-usbdrd.o
>>   obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)	+= phy-qcom-apq8064-sata.o
>> +obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
>>   obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)	+= phy-qcom-ipq806x-sata.o
>>   obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY)	+= phy-spear1310-miphy.o
>>   obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY)	+= phy-spear1340-miphy.o
>> diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
>> new file mode 100644
>> index 0000000..22011c3
>> --- /dev/null
>> +++ b/drivers/phy/phy-rockchip-usb.c
>> @@ -0,0 +1,158 @@
>> +/*
>> + * Rockchip usb PHY driver
>> + *
>> + * Copyright (C) 2014 Yunzhi Li <[email-masked]>
>> + * Copyright (C) 2014 ROCKCHIP, Inc.
>> + *
>> + * 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.
>> + *
>> + * 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/clk.h>
>> +#include <linux/io.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/mutex.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/phy/phy.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/reset.h>
>> +#include <linux/regmap.h>
>> +#include <linux/mfd/syscon.h>
>> +
>> +/*
>> + * The higher 16-bit of this register is used for write protection
>> + * only if BIT(13 + 16) set to 1 the BIT(13) can be written.
>> + */
>> +#define SIDDQ_WRITE_ENA	BIT(29)
>> +#define SIDDQ_ON		BIT(13)
>> +#define SIDDQ_OFF		(0 << 13)
>> +
>> +struct rockchip_usb_phy {
>> +	unsigned int	reg_offset;
>> +	struct regmap	*reg_base;
>> +	struct clk	*clk;
>> +	struct phy	*phy;
>> +};
>> +
>> +static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
>> +					   bool siddq)
>> +{
>> +	return regmap_write(phy->reg_base, phy->reg_offset,
>> +			    SIDDQ_WRITE_ENA | (siddq ? SIDDQ_ON : SIDDQ_OFF));
>> +}
>> +
>> +static int rockchip_usb_phy_power_off(struct phy *_phy)
>> +{
>> +	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
>> +	int ret = 0;
>> +
>> +	/* Power down usb phy analog blocks by set siddq 1 */
>> +	ret = rockchip_usb_phy_power(phy, 1);
>> +	if (ret)
>> +		return ret;
>> +
>> +	clk_disable_unprepare(phy->clk);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static int rockchip_usb_phy_power_on(struct phy *_phy)
>> +{
>> +	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
>> +	int ret = 0;
>> +
>> +	ret = clk_prepare_enable(phy->clk);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* Power up usb phy analog blocks by set siddq 0 */
>> +	ret = rockchip_usb_phy_power(phy, 0);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static struct phy_ops ops = {
>> +	.power_on	= rockchip_usb_phy_power_on,
>> +	.power_off	= rockchip_usb_phy_power_off,
>> +	.owner		= THIS_MODULE,
>> +};
>> +
>> +static int rockchip_usb_phy_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct rockchip_usb_phy *rk_phy;
>> +	struct phy_provider *phy_provider;
>> +	struct device_node *child;
>> +	struct regmap *grf;
>> +	unsigned int reg_offset;
>> +
>> +	grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
>> +	if (IS_ERR(grf)) {
>> +		dev_err(&pdev->dev, "Missing rockchip,grf property\n");
>> +		return PTR_ERR(grf);
>> +	}
>> +
>> +	for_each_available_child_of_node(dev->of_node, child) {
>> +		rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);
>> +		if (!rk_phy)
>> +			return -ENOMEM;
>> +
>> +		if (of_property_read_u32(child, "reg", &reg_offset)) {
>> +			dev_err(dev, "missing reg property in node %s\n",
>> +				child->name);
>> +			return -EINVAL;
>> +		}
>> +
>> +		rk_phy->reg_offset = reg_offset;
>> +		rk_phy->reg_base = grf;
>> +
>> +		rk_phy->clk = of_clk_get_by_name(child, "phyclk");
>> +		if (IS_ERR(rk_phy->clk))
>> +			rk_phy->clk = NULL;
>> +
>> +		rk_phy->phy = devm_phy_create(dev, child, &ops);
>> +		if (IS_ERR(rk_phy->phy)) {
>> +			dev_err(dev, "failed to create PHY\n");
>> +			return PTR_ERR(rk_phy->phy);
>> +		}
>> +		phy_set_drvdata(rk_phy->phy, rk_phy);
>> +	}
>> +
>> +	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 rockchip_usb_phy_dt_ids[] = {
>> +	{ .compatible = "rockchip,rk3288-usb-phy" },
> have you added devicetree binding documentation where I can find this
> compatible string?
>
> Thanks
> Kishon
>
>
You could find this documentation in this page :
https://lkml.org/lkml/2014/12/12/439
Thanks