Re: [PATCH v5 2/2] phy: qualcomm: Add Synopsys High-Speed USB PHY driver

[Kishon Vijay Abraham I]

Hi,

On 27/11/18 3:37 PM, Shawn Guo wrote:
> It adds Synopsys 28nm Femto High-Speed USB PHY driver support, which
> is usually paired with Synopsys DWC3 USB controllers on Qualcomm SoCs.

Is this Synopsys PHY specific to Qualcomm or could it be used by other vendors
(with just changing tuning parameters)? If it could be used by other vendors
then it would make sense to add this PHY driver in synopsys directory.

Thanks
Kishon
> 
> Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
> ---
>  drivers/phy/qualcomm/Kconfig                  |  10 +
>  drivers/phy/qualcomm/Makefile                 |   1 +
>  .../phy/qualcomm/phy-qcom-usb-hs-snsp-28nm.c  | 529 ++++++++++++++++++
>  3 files changed, 540 insertions(+)
>  create mode 100644 drivers/phy/qualcomm/phy-qcom-usb-hs-snsp-28nm.c
> 
> diff --git a/drivers/phy/qualcomm/Kconfig b/drivers/phy/qualcomm/Kconfig
> index 32f7d34eb784..c7b5ee82895d 100644
> --- a/drivers/phy/qualcomm/Kconfig
> +++ b/drivers/phy/qualcomm/Kconfig
> @@ -82,3 +82,13 @@ config PHY_QCOM_USB_HSIC
>  	select GENERIC_PHY
>  	help
>  	  Support for the USB HSIC ULPI compliant PHY on QCOM chipsets.
> +
> +config PHY_QCOM_USB_HS_SNPS_28NM
> +	tristate "Qualcomm Synopsys 28nm USB HS PHY driver"
> +	depends on ARCH_QCOM || COMPILE_TEST
> +	depends on EXTCON || !EXTCON # if EXTCON=m, this cannot be built-in
> +	select GENERIC_PHY
> +	help
> +	  Enable this to support the Synopsys 28nm Femto USB PHY on Qualcomm
> +	  chips. This driver supports the high-speed PHY which is usually
> +	  paired with either the ChipIdea or Synopsys DWC3 USB IPs on MSM SOCs.
> diff --git a/drivers/phy/qualcomm/Makefile b/drivers/phy/qualcomm/Makefile
> index c56efd3af205..dc238d95b18c 100644
> --- a/drivers/phy/qualcomm/Makefile
> +++ b/drivers/phy/qualcomm/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_PHY_QCOM_UFS_14NM)		+= phy-qcom-ufs-qmp-14nm.o
>  obj-$(CONFIG_PHY_QCOM_UFS_20NM)		+= phy-qcom-ufs-qmp-20nm.o
>  obj-$(CONFIG_PHY_QCOM_USB_HS) 		+= phy-qcom-usb-hs.o
>  obj-$(CONFIG_PHY_QCOM_USB_HSIC) 	+= phy-qcom-usb-hsic.o
> +obj-$(CONFIG_PHY_QCOM_USB_HS_SNPS_28NM)	+= phy-qcom-usb-hs-snsp-28nm.o
> diff --git a/drivers/phy/qualcomm/phy-qcom-usb-hs-snsp-28nm.c b/drivers/phy/qualcomm/phy-qcom-usb-hs-snsp-28nm.c
> new file mode 100644
> index 000000000000..1fa364417237
> --- /dev/null
> +++ b/drivers/phy/qualcomm/phy-qcom-usb-hs-snsp-28nm.c
> @@ -0,0 +1,529 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2009-2018, Linux Foundation. All rights reserved.
> + * Copyright (c) 2018, Linaro Limited
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/extcon.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/notifier.h>
> +#include <linux/of.h>
> +#include <linux/of_graph.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +
> +/* PHY register and bit definitions */
> +#define PHY_CTRL_COMMON0		0x078
> +#define SIDDQ				BIT(2)
> +#define PHY_IRQ_CMD			0x0d0
> +#define PHY_INTR_MASK0			0x0d4
> +#define PHY_INTR_CLEAR0			0x0dc
> +#define DPDM_MASK			0x1e
> +#define DP_1_0				BIT(4)
> +#define DP_0_1				BIT(3)
> +#define DM_1_0				BIT(2)
> +#define DM_0_1				BIT(1)
> +
> +enum hsphy_voltage {
> +	VOL_NONE,
> +	VOL_MIN,
> +	VOL_MAX,
> +	VOL_NUM,
> +};
> +
> +enum hsphy_vreg {
> +	VDD,
> +	VDDA_1P8,
> +	VDDA_3P3,
> +	VREG_NUM,
> +};
> +
> +struct hsphy_init_seq {
> +	int offset;
> +	int val;
> +	int delay;
> +};
> +
> +struct hsphy_data {
> +	const struct hsphy_init_seq *init_seq;
> +	unsigned int init_seq_num;
> +};
> +
> +struct hsphy_priv {
> +	void __iomem *base;
> +	struct clk_bulk_data *clks;
> +	int num_clks;
> +	struct reset_control *phy_reset;
> +	struct reset_control *por_reset;
> +	struct regulator_bulk_data vregs[VREG_NUM];
> +	unsigned int voltages[VREG_NUM][VOL_NUM];
> +	const struct hsphy_data *data;
> +	bool cable_connected;
> +	struct extcon_dev *vbus_edev;
> +	struct notifier_block vbus_notify;
> +	enum phy_mode mode;
> +};
> +
> +static int qcom_snps_hsphy_config_regulators(struct hsphy_priv *priv, int high)
> +{
> +	int old_uV[VREG_NUM];
> +	int min, ret, i;
> +
> +	min = high ? 1 : 0; /* low or none? */
> +
> +	for (i = 0; i < VREG_NUM; i++) {
> +		old_uV[i] = regulator_get_voltage(priv->vregs[i].consumer);
> +		ret = regulator_set_voltage(priv->vregs[i].consumer,
> +					    priv->voltages[i][min],
> +					    priv->voltages[i][VOL_MAX]);
> +		if (ret)
> +			goto roll_back;
> +	}
> +
> +	return 0;
> +
> +roll_back:
> +	for (; i >= 0; i--)
> +		regulator_set_voltage(priv->vregs[i].consumer,
> +				      old_uV[i], old_uV[i]);
> +	return ret;
> +}
> +
> +static int qcom_snps_hsphy_enable_regulators(struct hsphy_priv *priv)
> +{
> +	int ret;
> +
> +	ret = qcom_snps_hsphy_config_regulators(priv, 1);
> +	if (ret)
> +		return ret;
> +
> +	ret = regulator_set_load(priv->vregs[VDDA_1P8].consumer, 19000);
> +	if (ret < 0)
> +		goto unconfig_regulators;
> +
> +	ret = regulator_set_load(priv->vregs[VDDA_3P3].consumer, 16000);
> +	if (ret < 0)
> +		goto unset_1p8_load;
> +
> +	ret = regulator_bulk_enable(VREG_NUM, priv->vregs);
> +	if (ret)
> +		goto unset_3p3_load;
> +
> +	return 0;
> +
> +unset_3p3_load:
> +	regulator_set_load(priv->vregs[VDDA_3P3].consumer, 0);
> +unset_1p8_load:
> +	regulator_set_load(priv->vregs[VDDA_1P8].consumer, 0);
> +unconfig_regulators:
> +	qcom_snps_hsphy_config_regulators(priv, 0);
> +	return ret;
> +}
> +
> +static void qcom_snps_hsphy_disable_regulators(struct hsphy_priv *priv)
> +{
> +	regulator_bulk_disable(VREG_NUM, priv->vregs);
> +	regulator_set_load(priv->vregs[VDDA_1P8].consumer, 0);
> +	regulator_set_load(priv->vregs[VDDA_3P3].consumer, 0);
> +	qcom_snps_hsphy_config_regulators(priv, 0);
> +}
> +
> +static int qcom_snps_hsphy_set_mode(struct phy *phy, enum phy_mode mode)
> +{
> +	struct hsphy_priv *priv = phy_get_drvdata(phy);
> +
> +	priv->mode = mode;
> +
> +	return 0;
> +}
> +
> +static void qcom_snps_hsphy_enable_hv_interrupts(struct hsphy_priv *priv)
> +{
> +	u32 val;
> +
> +	/* Clear any existing interrupts before enabling the interrupts */
> +	val = readb(priv->base + PHY_INTR_CLEAR0);
> +	val |= DPDM_MASK;
> +	writeb(val, priv->base + PHY_INTR_CLEAR0);
> +
> +	writeb(0x0, priv->base + PHY_IRQ_CMD);
> +	usleep_range(200, 220);
> +	writeb(0x1, priv->base + PHY_IRQ_CMD);
> +
> +	/* Make sure the interrupts are cleared */
> +	usleep_range(200, 220);
> +
> +	val = readb(priv->base + PHY_INTR_MASK0);
> +	switch (priv->mode) {
> +	case PHY_MODE_USB_HOST_HS:
> +	case PHY_MODE_USB_HOST_FS:
> +	case PHY_MODE_USB_DEVICE_HS:
> +	case PHY_MODE_USB_DEVICE_FS:
> +		val |= DP_1_0 | DM_0_1;
> +		break;
> +	case PHY_MODE_USB_HOST_LS:
> +	case PHY_MODE_USB_DEVICE_LS:
> +		val |= DP_0_1 | DM_1_0;
> +		break;
> +	default:
> +		/* No device connected */
> +		val |= DP_0_1 | DM_0_1;
> +		break;
> +	}
> +	writeb(val, priv->base + PHY_INTR_MASK0);
> +}
> +
> +static void qcom_snps_hsphy_disable_hv_interrupts(struct hsphy_priv *priv)
> +{
> +	u32 val;
> +
> +	val = readb(priv->base + PHY_INTR_MASK0);
> +	val &= ~DPDM_MASK;
> +	writeb(val, priv->base + PHY_INTR_MASK0);
> +
> +	/* Clear any pending interrupts */
> +	val = readb(priv->base + PHY_INTR_CLEAR0);
> +	val |= DPDM_MASK;
> +	writeb(val, priv->base + PHY_INTR_CLEAR0);
> +
> +	writeb(0x0, priv->base + PHY_IRQ_CMD);
> +	usleep_range(200, 220);
> +
> +	writeb(0x1, priv->base + PHY_IRQ_CMD);
> +	usleep_range(200, 220);
> +}
> +
> +static void qcom_snps_hsphy_enter_retention(struct hsphy_priv *priv)
> +{
> +	u32 val;
> +
> +	val = readb(priv->base + PHY_CTRL_COMMON0);
> +	val |= SIDDQ;
> +	writeb(val, priv->base + PHY_CTRL_COMMON0);
> +}
> +
> +static void qcom_snps_hsphy_exit_retention(struct hsphy_priv *priv)
> +{
> +	u32 val;
> +
> +	val = readb(priv->base + PHY_CTRL_COMMON0);
> +	val &= ~SIDDQ;
> +	writeb(val, priv->base + PHY_CTRL_COMMON0);
> +}
> +
> +static int qcom_snps_hsphy_vbus_notifier(struct notifier_block *nb,
> +					 unsigned long event, void *ptr)
> +{
> +	struct hsphy_priv *priv = container_of(nb, struct hsphy_priv,
> +						    vbus_notify);
> +	priv->cable_connected = !!event;
> +	return 0;
> +}
> +
> +static int qcom_snps_hsphy_power_on(struct phy *phy)
> +{
> +	struct hsphy_priv *priv = phy_get_drvdata(phy);
> +	int ret;
> +
> +	if (priv->cable_connected) {
> +		ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
> +		if (ret)
> +			return ret;
> +		qcom_snps_hsphy_disable_hv_interrupts(priv);
> +	} else {
> +		ret = qcom_snps_hsphy_enable_regulators(priv);
> +		if (ret)
> +			return ret;
> +		ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
> +		if (ret)
> +			return ret;
> +		qcom_snps_hsphy_exit_retention(priv);
> +	}
> +
> +	return 0;
> +}
> +
> +static int qcom_snps_hsphy_power_off(struct phy *phy)
> +{
> +	struct hsphy_priv *priv = phy_get_drvdata(phy);
> +
> +	if (priv->cable_connected) {
> +		qcom_snps_hsphy_enable_hv_interrupts(priv);
> +		clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
> +	} else {
> +		qcom_snps_hsphy_enter_retention(priv);
> +		clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
> +		qcom_snps_hsphy_disable_regulators(priv);
> +	}
> +
> +	return 0;
> +}
> +
> +static int qcom_snps_hsphy_reset(struct hsphy_priv *priv)
> +{
> +	int ret;
> +
> +	ret = reset_control_assert(priv->phy_reset);
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(10, 15);
> +
> +	ret = reset_control_deassert(priv->phy_reset);
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(80, 100);
> +
> +	return 0;
> +}
> +
> +static void qcom_snps_hsphy_init_sequence(struct hsphy_priv *priv)
> +{
> +	const struct hsphy_data *data = priv->data;
> +	const struct hsphy_init_seq *seq;
> +	int i;
> +
> +	/* Device match data is optional. */
> +	if (!data)
> +		return;
> +
> +	seq = data->init_seq;
> +
> +	for (i = 0; i < data->init_seq_num; i++, seq++) {
> +		writeb(seq->val, priv->base + seq->offset);
> +		if (seq->delay)
> +			usleep_range(seq->delay, seq->delay + 10);
> +	}
> +}
> +
> +static int qcom_snps_hsphy_por_reset(struct hsphy_priv *priv)
> +{
> +	int ret;
> +
> +	ret = reset_control_assert(priv->por_reset);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * The Femto PHY is POR reset in the following scenarios.
> +	 *
> +	 * 1. After overriding the parameter registers.
> +	 * 2. Low power mode exit from PHY retention.
> +	 *
> +	 * Ensure that SIDDQ is cleared before bringing the PHY
> +	 * out of reset.
> +	 */
> +	qcom_snps_hsphy_exit_retention(priv);
> +
> +	/*
> +	 * As per databook, 10 usec delay is required between
> +	 * PHY POR assert and de-assert.
> +	 */
> +	usleep_range(10, 20);
> +	ret = reset_control_deassert(priv->por_reset);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * As per databook, it takes 75 usec for PHY to stabilize
> +	 * after the reset.
> +	 */
> +	usleep_range(80, 100);
> +
> +	return 0;
> +}
> +
> +static int qcom_snps_hsphy_init(struct phy *phy)
> +{
> +	struct hsphy_priv *priv = phy_get_drvdata(phy);
> +	int state;
> +	int ret;
> +
> +	ret = qcom_snps_hsphy_reset(priv);
> +	if (ret)
> +		return ret;
> +
> +	qcom_snps_hsphy_init_sequence(priv);
> +
> +	ret = qcom_snps_hsphy_por_reset(priv);
> +	if (ret)
> +		return ret;
> +
> +	/* Setup initial state */
> +	if (priv->vbus_edev) {
> +		state = extcon_get_state(priv->vbus_edev, EXTCON_USB);
> +		ret = qcom_snps_hsphy_vbus_notifier(&priv->vbus_notify, state,
> +						    priv->vbus_edev);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct phy_ops qcom_snps_hsphy_ops = {
> +	.init = qcom_snps_hsphy_init,
> +	.power_on = qcom_snps_hsphy_power_on,
> +	.power_off = qcom_snps_hsphy_power_off,
> +	.set_mode = qcom_snps_hsphy_set_mode,
> +	.owner = THIS_MODULE,
> +};
> +
> +static const char * const qcom_snps_hsphy_clks[] = {
> +	"ref",
> +	"phy",
> +	"sleep",
> +};
> +
> +static int qcom_snps_hsphy_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *extcon_node;
> +	struct phy_provider *provider;
> +	struct hsphy_priv *priv;
> +	struct resource *res;
> +	struct phy *phy;
> +	int ret;
> +	int i;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	priv->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	priv->num_clks = ARRAY_SIZE(qcom_snps_hsphy_clks);
> +	priv->clks = devm_kcalloc(dev, priv->num_clks, sizeof(*priv->clks),
> +				  GFP_KERNEL);
> +	if (!priv->clks)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < priv->num_clks; i++)
> +		priv->clks[i].id = qcom_snps_hsphy_clks[i];
> +
> +	ret = devm_clk_bulk_get(dev, priv->num_clks, priv->clks);
> +	if (ret)
> +		return ret;
> +
> +	priv->phy_reset = devm_reset_control_get(dev, "phy");
> +	if (IS_ERR(priv->phy_reset))
> +		return PTR_ERR(priv->phy_reset);
> +
> +	priv->por_reset = devm_reset_control_get(dev, "por");
> +	if (IS_ERR(priv->por_reset))
> +		return PTR_ERR(priv->por_reset);
> +
> +	priv->vregs[VDD].supply = "vdd";
> +	priv->vregs[VDDA_1P8].supply = "vdda1p8";
> +	priv->vregs[VDDA_3P3].supply = "vdda3p3";
> +
> +	ret = devm_regulator_bulk_get(dev, VREG_NUM, priv->vregs);
> +	if (ret)
> +		return ret;
> +
> +	priv->voltages[VDDA_1P8][VOL_NONE] = 0;
> +	priv->voltages[VDDA_1P8][VOL_MIN] = 1800000;
> +	priv->voltages[VDDA_1P8][VOL_MAX] = 1800000;
> +
> +	priv->voltages[VDDA_3P3][VOL_NONE] = 0;
> +	priv->voltages[VDDA_3P3][VOL_MIN] = 3050000;
> +	priv->voltages[VDDA_3P3][VOL_MAX] = 3300000;
> +
> +	ret = of_property_read_u32_array(dev->of_node, "qcom,vdd-voltage-level",
> +					 priv->voltages[VDD], VOL_NUM);
> +	if (ret) {
> +		dev_err(dev, "failed to read qcom,vdd-voltage-level\n");
> +		return ret;
> +	}
> +
> +	extcon_node = of_graph_get_remote_node(dev->of_node, -1, -1);
> +	if (extcon_node) {
> +		priv->vbus_edev = extcon_find_edev_by_node(extcon_node);
> +		if (IS_ERR(priv->vbus_edev)) {
> +			if (PTR_ERR(priv->vbus_edev) != -ENODEV) {
> +				of_node_put(extcon_node);
> +				return PTR_ERR(priv->vbus_edev);
> +			}
> +			priv->vbus_edev = NULL;
> +		}
> +	}
> +	of_node_put(extcon_node);
> +
> +	if (priv->vbus_edev) {
> +		priv->vbus_notify.notifier_call = qcom_snps_hsphy_vbus_notifier;
> +		ret = devm_extcon_register_notifier(dev, priv->vbus_edev,
> +						    EXTCON_USB,
> +						    &priv->vbus_notify);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	/* Get device match data */
> +	priv->data = device_get_match_data(dev);
> +
> +	phy = devm_phy_create(dev, dev->of_node, &qcom_snps_hsphy_ops);
> +	if (IS_ERR(phy))
> +		return PTR_ERR(phy);
> +
> +	phy_set_drvdata(phy, priv);
> +
> +	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +	return PTR_ERR_OR_ZERO(provider);
> +}
> +
> +/*
> + * The macro is used to define an initialization sequence.  Each tuple
> + * is meant to program 'value' into phy register at 'offset' with 'delay'
> + * in us followed.
> + */
> +#define HSPHY_INIT_CFG(o, v, d)	{ .offset = o, .val = v, .delay = d, }
> +
> +static const struct hsphy_init_seq init_seq_qcs404[] = {
> +	HSPHY_INIT_CFG(0xc0, 0x01, 0),
> +	HSPHY_INIT_CFG(0xe8, 0x0d, 0),
> +	HSPHY_INIT_CFG(0x74, 0x12, 0),
> +	HSPHY_INIT_CFG(0x98, 0x63, 0),
> +	HSPHY_INIT_CFG(0x9c, 0x03, 0),
> +	HSPHY_INIT_CFG(0xa0, 0x1d, 0),
> +	HSPHY_INIT_CFG(0xa4, 0x03, 0),
> +	HSPHY_INIT_CFG(0x8c, 0x23, 0),
> +	HSPHY_INIT_CFG(0x78, 0x08, 0),
> +	HSPHY_INIT_CFG(0x7c, 0xdc, 0),
> +	HSPHY_INIT_CFG(0x90, 0xe0, 20),
> +	HSPHY_INIT_CFG(0x74, 0x10, 0),
> +	HSPHY_INIT_CFG(0x90, 0x60, 0),
> +};
> +
> +static const struct hsphy_data hsphy_data_qcs404 = {
> +	.init_seq = init_seq_qcs404,
> +	.init_seq_num = ARRAY_SIZE(init_seq_qcs404),
> +};
> +
> +static const struct of_device_id qcom_snps_hsphy_match[] = {
> +	{ .compatible = "qcom,qcs404-usb-hsphy", .data = &hsphy_data_qcs404, },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, qcom_snps_hsphy_match);
> +
> +static struct platform_driver qcom_snps_hsphy_driver = {
> +	.probe = qcom_snps_hsphy_probe,
> +	.driver	= {
> +		.name = "qcom-usb-snps-hsphy",
> +		.of_match_table = qcom_snps_hsphy_match,
> +	},
> +};
> +module_platform_driver(qcom_snps_hsphy_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm Synopsys 28nm USB High-Speed PHY driver");
> +MODULE_LICENSE("GPL v2");
>