Re: [̈́PATCHv4 12/12] phy: add driver for TI TUSB1210 ULPI PHY

[Kishon Vijay Abraham I <kishon@ti.com>]

On Thursday 07 May 2015 11:49 AM, Heikki Krogerus wrote:
> TUSB1210 ULPI PHY has vendor specific register for eye
> diagram tuning. On some platforms the system firmware has
> set optimized value to it. In order to not loose the
> optimized value, the driver stores it during probe and
> restores it every time the PHY is powered back on.
>
> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Acked-by: David Cohen <david.a.cohen@linux.intel.com>
> Cc: Kishon Vijay Abraham I <kishon@ti.com>

Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
>   drivers/phy/Kconfig        |   7 +++
>   drivers/phy/Makefile       |   1 +
>   drivers/phy/phy-tusb1210.c | 153 +++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 161 insertions(+)
>   create mode 100644 drivers/phy/phy-tusb1210.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index a53bd5b..fceac96 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -309,4 +309,11 @@ config PHY_QCOM_UFS
>   	help
>   	  Support for UFS PHY on QCOM chipsets.
>
> +config PHY_TUSB1210
> +	tristate "TI TUSB1210 ULPI PHY module"
> +	depends on USB_ULPI_BUS
> +	select GENERIC_PHY
> +	help
> +	  Support for TI TUSB1210 USB ULPI PHY.
> +
>   endmenu
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index f126251..0a20418 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -40,3 +40,4 @@ obj-$(CONFIG_PHY_STIH41X_USB)		+= phy-stih41x-usb.o
>   obj-$(CONFIG_PHY_QCOM_UFS) 	+= phy-qcom-ufs.o
>   obj-$(CONFIG_PHY_QCOM_UFS) 	+= phy-qcom-ufs-qmp-20nm.o
>   obj-$(CONFIG_PHY_QCOM_UFS) 	+= phy-qcom-ufs-qmp-14nm.o
> +obj-$(CONFIG_PHY_TUSB1210)		+= phy-tusb1210.o
> diff --git a/drivers/phy/phy-tusb1210.c b/drivers/phy/phy-tusb1210.c
> new file mode 100644
> index 0000000..07efdd3
> --- /dev/null
> +++ b/drivers/phy/phy-tusb1210.c
> @@ -0,0 +1,153 @@
> +/**
> + * tusb1210.c - TUSB1210 USB ULPI PHY driver
> + *
> + * Copyright (C) 2015 Intel Corporation
> + *
> + * Author: Heikki Krogerus <heikki.krogerus@linux.intel.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/module.h>
> +#include <linux/ulpi/driver.h>
> +#include <linux/gpio/consumer.h>
> +
> +#include "ulpi_phy.h"
> +
> +#define TUSB1210_VENDOR_SPECIFIC2		0x80
> +#define TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT	0
> +#define TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT	4
> +#define TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT	6
> +
> +struct tusb1210 {
> +	struct ulpi *ulpi;
> +	struct phy *phy;
> +	struct gpio_desc *gpio_reset;
> +	struct gpio_desc *gpio_cs;
> +	u8 vendor_specific2;
> +};
> +
> +static int tusb1210_power_on(struct phy *phy)
> +{
> +	struct tusb1210 *tusb = phy_get_drvdata(phy);
> +
> +	gpiod_set_value_cansleep(tusb->gpio_reset, 1);
> +	gpiod_set_value_cansleep(tusb->gpio_cs, 1);
> +
> +	/* Restore the optional eye diagram optimization value */
> +	if (tusb->vendor_specific2)
> +		ulpi_write(tusb->ulpi, TUSB1210_VENDOR_SPECIFIC2,
> +			   tusb->vendor_specific2);
> +
> +	return 0;
> +}
> +
> +static int tusb1210_power_off(struct phy *phy)
> +{
> +	struct tusb1210 *tusb = phy_get_drvdata(phy);
> +
> +	gpiod_set_value_cansleep(tusb->gpio_reset, 0);
> +	gpiod_set_value_cansleep(tusb->gpio_cs, 0);
> +
> +	return 0;
> +}
> +
> +static struct phy_ops phy_ops = {
> +	.power_on = tusb1210_power_on,
> +	.power_off = tusb1210_power_off,
> +	.owner = THIS_MODULE,
> +};
> +
> +static int tusb1210_probe(struct ulpi *ulpi)
> +{
> +	struct gpio_desc *gpio;
> +	struct tusb1210 *tusb;
> +	u8 val, reg;
> +	int ret;
> +
> +	tusb = devm_kzalloc(&ulpi->dev, sizeof(*tusb), GFP_KERNEL);
> +	if (!tusb)
> +		return -ENOMEM;
> +
> +	gpio = devm_gpiod_get(&ulpi->dev, "reset");
> +	if (!IS_ERR(gpio)) {
> +		ret = gpiod_direction_output(gpio, 0);
> +		if (ret)
> +			return ret;
> +		gpiod_set_value_cansleep(gpio, 1);
> +		tusb->gpio_reset = gpio;
> +	}
> +
> +	gpio = devm_gpiod_get(&ulpi->dev, "cs");
> +	if (!IS_ERR(gpio)) {
> +		ret = gpiod_direction_output(gpio, 0);
> +		if (ret)
> +			return ret;
> +		gpiod_set_value_cansleep(gpio, 1);
> +		tusb->gpio_cs = gpio;
> +	}
> +
> +	/*
> +	 * VENDOR_SPECIFIC2 register in TUSB1210 can be used for configuring eye
> +	 * diagram optimization and DP/DM swap.
> +	 */
> +
> +	/* High speed output drive strength configuration */
> +	device_property_read_u8(&ulpi->dev, "ihstx", &val);
> +	reg = val << TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT;
> +
> +	/* High speed output impedance configuration */
> +	device_property_read_u8(&ulpi->dev, "zhsdrv", &val);
> +	reg |= val << TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT;
> +
> +	/* DP/DM swap control */
> +	device_property_read_u8(&ulpi->dev, "datapolarity", &val);
> +	reg |= val << TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT;
> +
> +	if (reg) {
> +		ulpi_write(ulpi, TUSB1210_VENDOR_SPECIFIC2, reg);
> +		tusb->vendor_specific2 = reg;
> +	}
> +
> +	tusb->phy = ulpi_phy_create(ulpi, &phy_ops);
> +	if (IS_ERR(tusb->phy))
> +		return PTR_ERR(tusb->phy);
> +
> +	tusb->ulpi = ulpi;
> +
> +	phy_set_drvdata(tusb->phy, tusb);
> +	ulpi_set_drvdata(ulpi, tusb);
> +	return 0;
> +}
> +
> +static void tusb1210_remove(struct ulpi *ulpi)
> +{
> +	struct tusb1210 *tusb = ulpi_get_drvdata(ulpi);
> +
> +	ulpi_phy_destroy(ulpi, tusb->phy);
> +}
> +
> +#define TI_VENDOR_ID 0x0451
> +
> +static const struct ulpi_device_id tusb1210_ulpi_id[] = {
> +	{ TI_VENDOR_ID, 0x1507, },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(ulpi, tusb1210_ulpi_id);
> +
> +static struct ulpi_driver tusb1210_driver = {
> +	.id_table = tusb1210_ulpi_id,
> +	.probe = tusb1210_probe,
> +	.remove = tusb1210_remove,
> +	.driver = {
> +		.name = "tusb1210",
> +		.owner = THIS_MODULE,
> +	},
> +};
> +
> +module_ulpi_driver(tusb1210_driver);
> +
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("TUSB1210 ULPI PHY driver");
>