Message-ID: <20150429183647.GC9169@x1>
Date:	Wed, 29 Apr 2015 19:36:47 +0100
From:	Lee Jones <lee.jones@...aro.org>
To:	Ramakrishna Pallala <ramakrishna.pallala@...el.com>
Cc:	linux-kernel@...r.kernel.org, Chanwoo Choi <cwchoi00@...il.com>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Jacob Pan <jacob.jun.pan@...ux.intel.com>
Subject: Re: [PATCH v8] extcon-axp288: Add axp288 extcon driver support

On Thu, 30 Apr 2015, Ramakrishna Pallala wrote:

> This patch adds the extcon support for AXP288 PMIC which
> has the BC1.2 charger detection capability. Additionally
> it also adds the USB mux switching support b/w SOC and PMIC
> based on GPIO control.
> 
> Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@...el.com>

When you send next versions, the convention is for you to apply Acks
that you've collected.

> ---
>  drivers/extcon/Kconfig         |    7 +
>  drivers/extcon/Makefile        |    1 +
>  drivers/extcon/extcon-axp288.c |  386 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/axp20x.h     |    5 +
>  4 files changed, 399 insertions(+)
>  create mode 100644 drivers/extcon/extcon-axp288.c
> 
> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> index fdc0bf0..2305edc 100644
> --- a/drivers/extcon/Kconfig
> +++ b/drivers/extcon/Kconfig
> @@ -28,6 +28,13 @@ config EXTCON_ARIZONA
>  	  with Wolfson Arizona devices. These are audio CODECs with
>  	  advanced audio accessory detection support.
>  
> +config EXTCON_AXP288
> +	tristate "X-Power AXP288 EXTCON support"
> +	depends on MFD_AXP20X && USB_PHY
> +	help
> +	  Say Y here to enable support for USB peripheral detection
> +	  and USB MUX switching by X-Power AXP288 PMIC.
> +
>  config EXTCON_GPIO
>  	tristate "GPIO extcon support"
>  	depends on GPIOLIB
> diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
> index 9204114..ba787d0 100644
> --- a/drivers/extcon/Makefile
> +++ b/drivers/extcon/Makefile
> @@ -5,6 +5,7 @@
>  obj-$(CONFIG_EXTCON)		+= extcon.o
>  obj-$(CONFIG_EXTCON_ADC_JACK)	+= extcon-adc-jack.o
>  obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o
> +obj-$(CONFIG_EXTCON_AXP288)	+= extcon-axp288.o
>  obj-$(CONFIG_EXTCON_GPIO)	+= extcon-gpio.o
>  obj-$(CONFIG_EXTCON_MAX14577)	+= extcon-max14577.o
>  obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o
> diff --git a/drivers/extcon/extcon-axp288.c b/drivers/extcon/extcon-axp288.c
> new file mode 100644
> index 0000000..ea61bf2
> --- /dev/null
> +++ b/drivers/extcon/extcon-axp288.c
> @@ -0,0 +1,386 @@
> +/*
> + * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver
> + *
> + * Copyright (C) 2015 Intel Corporation
> + * Author: Ramakrishna Pallala <ramakrishna.pallala@...el.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.
> + *
> + * 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/module.h>
> +#include <linux/kernel.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/usb/phy.h>
> +#include <linux/notifier.h>
> +#include <linux/extcon.h>
> +#include <linux/regmap.h>
> +#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/mfd/axp20x.h>
> +
> +/* Power source status register */
> +#define PS_STAT_VBUS_TRIGGER		BIT(0)
> +#define PS_STAT_BAT_CHRG_DIR		BIT(2)
> +#define PS_STAT_VBUS_ABOVE_VHOLD	BIT(3)
> +#define PS_STAT_VBUS_VALID		BIT(4)
> +#define PS_STAT_VBUS_PRESENT		BIT(5)
> +
> +/* BC module global register */
> +#define BC_GLOBAL_RUN			BIT(0)
> +#define BC_GLOBAL_DET_STAT		BIT(2)
> +#define BC_GLOBAL_DBP_TOUT		BIT(3)
> +#define BC_GLOBAL_VLGC_COM_SEL		BIT(4)
> +#define BC_GLOBAL_DCD_TOUT_MASK		(BIT(6)|BIT(5))
> +#define BC_GLOBAL_DCD_TOUT_300MS	0
> +#define BC_GLOBAL_DCD_TOUT_100MS	1
> +#define BC_GLOBAL_DCD_TOUT_500MS	2
> +#define BC_GLOBAL_DCD_TOUT_900MS	3
> +#define BC_GLOBAL_DCD_DET_SEL		BIT(7)
> +
> +/* BC module vbus control and status register */
> +#define VBUS_CNTL_DPDM_PD_EN		BIT(4)
> +#define VBUS_CNTL_DPDM_FD_EN		BIT(5)
> +#define VBUS_CNTL_FIRST_PO_STAT		BIT(6)
> +
> +/* BC USB status register */
> +#define USB_STAT_BUS_STAT_MASK		(BIT(3)|BIT(2)|BIT(1)|BIT(0))
> +#define USB_STAT_BUS_STAT_SHIFT		0
> +#define USB_STAT_BUS_STAT_ATHD		0
> +#define USB_STAT_BUS_STAT_CONN		1
> +#define USB_STAT_BUS_STAT_SUSP		2
> +#define USB_STAT_BUS_STAT_CONF		3
> +#define USB_STAT_USB_SS_MODE		BIT(4)
> +#define USB_STAT_DEAD_BAT_DET		BIT(6)
> +#define USB_STAT_DBP_UNCFG		BIT(7)
> +
> +/* BC detect status register */
> +#define DET_STAT_MASK			(BIT(7)|BIT(6)|BIT(5))
> +#define DET_STAT_SHIFT			5
> +#define DET_STAT_SDP			1
> +#define DET_STAT_CDP			2
> +#define DET_STAT_DCP			3
> +
> +/* IRQ enable-1 register */
> +#define PWRSRC_IRQ_CFG_MASK		(BIT(4)|BIT(3)|BIT(2))
> +
> +/* IRQ enable-6 register */
> +#define BC12_IRQ_CFG_MASK		BIT(1)
> +
> +#define AXP288_EXTCON_SLOW_CHARGER		"SLOW-CHARGER"
> +#define AXP288_EXTCON_DOWNSTREAM_CHARGER	"CHARGE-DOWNSTREAM"
> +#define AXP288_EXTCON_FAST_CHARGER		"FAST-CHARGER"
> +
> +enum axp288_extcon_reg {
> +	AXP288_PS_STAT_REG		= 0x00,
> +	AXP288_PS_BOOT_REASON_REG	= 0x02,
> +	AXP288_BC_GLOBAL_REG		= 0x2c,
> +	AXP288_BC_VBUS_CNTL_REG		= 0x2d,
> +	AXP288_BC_USB_STAT_REG		= 0x2e,
> +	AXP288_BC_DET_STAT_REG		= 0x2f,
> +	AXP288_PWRSRC_IRQ_CFG_REG	= 0x40,
> +	AXP288_BC12_IRQ_CFG_REG		= 0x45,
> +};
> +
> +enum axp288_mux_select {
> +	EXTCON_GPIO_MUX_SEL_PMIC = 0,
> +	EXTCON_GPIO_MUX_SEL_SOC,
> +};
> +
> +enum axp288_extcon_irq {
> +	VBUS_FALLING_IRQ = 0,
> +	VBUS_RISING_IRQ,
> +	MV_CHNG_IRQ,
> +	BC_USB_CHNG_IRQ,
> +	EXTCON_IRQ_END,
> +};
> +
> +static const char *axp288_extcon_cables[] = {
> +	AXP288_EXTCON_SLOW_CHARGER,
> +	AXP288_EXTCON_DOWNSTREAM_CHARGER,
> +	AXP288_EXTCON_FAST_CHARGER,
> +	NULL,
> +};
> +
> +struct axp288_extcon_info {
> +	struct device *dev;
> +	struct regmap *regmap;
> +	struct regmap_irq_chip_data *regmap_irqc;
> +	struct axp288_extcon_pdata *pdata;
> +	int irq[EXTCON_IRQ_END];
> +	struct extcon_dev *edev;
> +	struct notifier_block extcon_nb;
> +	struct usb_phy *otg;
> +};
> +
> +/* Power up/down reason string array */
> +static char *axp288_pwr_up_down_info[] = {
> +	"Last wake caused by user pressing the power button",
> +	"Last wake caused by a charger insertion",
> +	"Last wake caused by a battery insertion",
> +	"Last wake caused by SOC initiated global reset",
> +	"Last wake caused by cold reset",
> +	"Last shutdown caused by PMIC UVLO threshold",
> +	"Last shutdown caused by SOC initiated cold off",
> +	"Last shutdown caused by user pressing the power button",
> +	NULL,
> +};
> +
> +/*
> + * Decode and log the given "reset source indicator" (rsi)
> + * register and then clear it.
> + */
> +static void axp288_extcon_log_rsi(struct axp288_extcon_info *info)
> +{
> +	char **rsi;
> +	unsigned int val, i, clear_mask = 0;
> +	int ret;
> +
> +	ret = regmap_read(info->regmap, AXP288_PS_BOOT_REASON_REG, &val);
> +	for (i = 0, rsi = axp288_pwr_up_down_info; *rsi; rsi++, i++) {
> +		if (val & BIT(i)) {
> +			dev_dbg(info->dev, "%s\n", *rsi);
> +			clear_mask |= BIT(i);
> +		}
> +	}
> +
> +	/* Clear the register value for next reboot (write 1 to clear bit) */
> +	regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask);
> +}
> +
> +static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info)
> +{
> +	static bool notify_otg, notify_charger;
> +	static char *cable;
> +	int ret, stat, cfg, pwr_stat;
> +	u8 chrg_type;
> +	bool vbus_attach = false;
> +
> +	ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat);
> +	if (ret < 0) {
> +		dev_err(info->dev, "failed to read vbus status\n");
> +		return ret;
> +	}
> +
> +	vbus_attach = (pwr_stat & PS_STAT_VBUS_PRESENT);
> +	if (!vbus_attach)
> +		goto notify_otg;
> +
> +	/* Check charger detection completion status */
> +	ret = regmap_read(info->regmap, AXP288_BC_GLOBAL_REG, &cfg);
> +	if (ret < 0)
> +		goto dev_det_ret;
> +	if (cfg & BC_GLOBAL_DET_STAT) {
> +		dev_dbg(info->dev, "can't complete the charger detection\n");
> +		goto dev_det_ret;
> +	}
> +
> +	ret = regmap_read(info->regmap, AXP288_BC_DET_STAT_REG, &stat);
> +	if (ret < 0)
> +		goto dev_det_ret;
> +	dev_dbg(info->dev, "status:%x, config:%x\n", stat, cfg);
> +
> +	chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_SHIFT;
> +
> +	switch (chrg_type) {
> +	case DET_STAT_SDP:
> +		dev_dbg(info->dev, "sdp cable is connecetd\n");
> +		notify_otg = true;
> +		notify_charger = true;
> +		cable = AXP288_EXTCON_SLOW_CHARGER;
> +		break;
> +	case DET_STAT_CDP:
> +		dev_dbg(info->dev, "cdp cable is connecetd\n");
> +		notify_otg = true;
> +		notify_charger = true;
> +		cable = AXP288_EXTCON_DOWNSTREAM_CHARGER;
> +		break;
> +	case DET_STAT_DCP:
> +		dev_dbg(info->dev, "dcp cable is connecetd\n");
> +		notify_charger = true;
> +		cable = AXP288_EXTCON_FAST_CHARGER;
> +		break;
> +	default:
> +		dev_warn(info->dev,
> +			"disconnect or unknown or ID event\n");
> +	}
> +
> +notify_otg:
> +	if (notify_otg) {
> +		/*
> +		 * If VBUS is absent Connect D+/D- lines to PMIC for BC
> +		 * detection. Else connect them to SOC for USB communication.
> +		 */
> +		if (info->pdata->gpio_mux_cntl)
> +			gpiod_set_value(info->pdata->gpio_mux_cntl,
> +				vbus_attach ? EXTCON_GPIO_MUX_SEL_SOC
> +						: EXTCON_GPIO_MUX_SEL_PMIC);
> +
> +		atomic_notifier_call_chain(&info->otg->notifier,
> +			vbus_attach ? USB_EVENT_VBUS : USB_EVENT_NONE, NULL);
> +	}
> +
> +	if (notify_charger)
> +		extcon_set_cable_state(info->edev, cable, vbus_attach);
> +
> +	/* Clear the flags on disconnect event */
> +	if (!vbus_attach)
> +		notify_otg = notify_charger = false;
> +
> +	return 0;
> +
> +dev_det_ret:
> +	if (ret < 0)
> +		dev_err(info->dev, "BC Mod detection error\n");
> +
> +	return ret;
> +}
> +
> +static irqreturn_t axp288_extcon_isr(int irq, void *data)
> +{
> +	struct axp288_extcon_info *info = data;
> +	int ret;
> +
> +	ret = axp288_handle_chrg_det_event(info);
> +	if (ret < 0)
> +		dev_err(info->dev, "error in PWRSRC INT handling\n");
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void axp288_extcon_enable_irq(struct axp288_extcon_info *info)
> +{
> +	/* Unmask VBUS interrupt */
> +	regmap_write(info->regmap, AXP288_PWRSRC_IRQ_CFG_REG,
> +						PWRSRC_IRQ_CFG_MASK);
> +	regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
> +						BC_GLOBAL_RUN, 0);
> +	/* Unmask the BC1.2 complete interrupts */
> +	regmap_write(info->regmap, AXP288_BC12_IRQ_CFG_REG, BC12_IRQ_CFG_MASK);
> +	/* Enable the charger detection logic */
> +	regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
> +					BC_GLOBAL_RUN, BC_GLOBAL_RUN);
> +}
> +
> +static int axp288_extcon_probe(struct platform_device *pdev)
> +{
> +	struct axp288_extcon_info *info;
> +	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
> +	int ret, i, pirq, gpio;
> +
> +	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
> +	if (!info)
> +		return -ENOMEM;
> +
> +	info->dev = &pdev->dev;
> +	info->regmap = axp20x->regmap;
> +	info->regmap_irqc = axp20x->regmap_irqc;
> +	info->pdata = pdev->dev.platform_data;
> +
> +	if (!info->pdata) {
> +		/* Try ACPI provided pdata via device properties */
> +		if (!device_property_present(&pdev->dev,
> +					"axp288_extcon_data\n"))
> +			dev_err(&pdev->dev, "failed to get platform data\n");
> +		return -ENODEV;
> +	}
> +	platform_set_drvdata(pdev, info);
> +
> +	axp288_extcon_log_rsi(info);
> +
> +	/* Initialize extcon device */
> +	info->edev = devm_extcon_dev_allocate(&pdev->dev,
> +					      axp288_extcon_cables);
> +	if (IS_ERR(info->edev)) {
> +		dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
> +		return PTR_ERR(info->edev);
> +	}
> +
> +	/* Register extcon device */
> +	ret = devm_extcon_dev_register(&pdev->dev, info->edev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to register extcon device\n");
> +		return ret;
> +	}
> +
> +	/* Get otg transceiver phy */
> +	info->otg = usb_get_phy(USB_PHY_TYPE_USB2);
> +	if (IS_ERR(info->otg)) {
> +		dev_warn(&pdev->dev, "failed to get otg transceiver\n");
> +		return PTR_ERR(info->otg);
> +	}
> +
> +	/* Set up gpio control for USB Mux */
> +	if (info->pdata->gpio_mux_cntl) {
> +		gpio = desc_to_gpio(info->pdata->gpio_mux_cntl);
> +		ret = gpio_request(gpio, "USB_MUX");
> +		if (ret < 0) {
> +			dev_err(&pdev->dev,
> +				"failed to request the gpio=%d\n", gpio);
> +			goto gpio_req_failed;
> +		}
> +		gpiod_direction_output(info->pdata->gpio_mux_cntl,
> +						EXTCON_GPIO_MUX_SEL_PMIC);
> +	}
> +
> +	for (i = 0; i < EXTCON_IRQ_END; i++) {
> +		pirq = platform_get_irq(pdev, i);
> +		info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
> +		if (info->irq[i] < 0) {
> +			dev_warn(&pdev->dev,
> +				"failed to get virtual interrupt=%d\n", pirq);
> +			ret = info->irq[i];
> +			goto gpio_req_failed;
> +		}
> +
> +		ret = devm_request_threaded_irq(&pdev->dev, info->irq[i],
> +				NULL, axp288_extcon_isr,
> +				IRQF_ONESHOT | IRQF_NO_SUSPEND,
> +				pdev->name, info);
> +		if (ret) {
> +			dev_err(&pdev->dev, "failed to request interrupt=%d\n",
> +							info->irq[i]);
> +			goto gpio_req_failed;
> +		}
> +	}
> +
> +	/* Enable interrupts */
> +	axp288_extcon_enable_irq(info);
> +
> +	return 0;
> +
> +gpio_req_failed:
> +	usb_put_phy(info->otg);
> +	return ret;
> +}
> +
> +static int axp288_extcon_remove(struct platform_device *pdev)
> +{
> +	struct axp288_extcon_info *info = platform_get_drvdata(pdev);
> +
> +	usb_put_phy(info->otg);
> +	return 0;
> +}
> +
> +static struct platform_driver axp288_extcon_driver = {
> +	.probe = axp288_extcon_probe,
> +	.remove = axp288_extcon_remove,
> +	.driver = {
> +		.name = "axp288_extcon",
> +	},
> +};
> +module_platform_driver(axp288_extcon_driver);
> +
> +MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@...el.com>");
> +MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
> index dfabd6d..4ed8071 100644
> --- a/include/linux/mfd/axp20x.h
> +++ b/include/linux/mfd/axp20x.h
> @@ -275,4 +275,9 @@ struct axp20x_fg_pdata {
>  	int thermistor_curve[MAX_THERM_CURVE_SIZE][2];
>  };
>  
> +struct axp288_extcon_pdata {
> +	/* GPIO pin control to switch D+/D- lines b/w PMIC and SOC */
> +	struct gpio_desc *gpio_mux_cntl;
> +};
> +
>  #endif /* __LINUX_MFD_AXP20X_H */

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists