Re: [PATCH v2 2/2] extcon-axp288: Add axp288 extcon driver support

[Lee Jones <lee.jones@linaro.org>]

On Fri, 03 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@intel.com>
> ---
>  drivers/extcon/Kconfig         |    7 +
>  drivers/extcon/Makefile        |    1 +
>  drivers/extcon/extcon-axp288.c |  479 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/axp20x.h     |    5 +

Acked-by: Lee Jones <lee.jones@linaro.org>

>  4 files changed, 492 insertions(+)
>  create mode 100644 drivers/extcon/extcon-axp288.c
> 
> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> index 6a1f7de..b8627f7 100644
> --- a/drivers/extcon/Kconfig
> +++ b/drivers/extcon/Kconfig
> @@ -93,4 +93,11 @@ config EXTCON_SM5502
>  	  Silicon Mitus SM5502. The SM5502 is a USB port accessory
>  	  detector and switch.
>  
> +config EXTCON_AXP288
> +	tristate "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 AXP288 PMIC.
> +
>  endif # MULTISTATE_SWITCH
> diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
> index 0370b42..832ad79 100644
> --- a/drivers/extcon/Makefile
> +++ b/drivers/extcon/Makefile
> @@ -12,3 +12,4 @@ obj-$(CONFIG_EXTCON_MAX8997)	+= extcon-max8997.o
>  obj-$(CONFIG_EXTCON_PALMAS)	+= extcon-palmas.o
>  obj-$(CONFIG_EXTCON_RT8973A)	+= extcon-rt8973a.o
>  obj-$(CONFIG_EXTCON_SM5502)	+= extcon-sm5502.o
> +obj-$(CONFIG_EXTCON_AXP288)	+= extcon-axp288.o
> diff --git a/drivers/extcon/extcon-axp288.c b/drivers/extcon/extcon-axp288.c
> new file mode 100644
> index 0000000..2e75d45
> --- /dev/null
> +++ b/drivers/extcon/extcon-axp288.c
> @@ -0,0 +1,479 @@
> +/*
> + * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver
> + *
> + * Copyright (C) 2015 Intel Corporation
> + * Ramakrishna Pallala <ramakrishna.pallala@intel.com>
> + *
> + * 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, or
> + * (at your option) any later version.
> + *
> + * 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>
> +
> +#define AXP288_PS_STAT_REG		0x00
> +#define PS_STAT_VBUS_TRIGGER		(1 << 0)
> +#define PS_STAT_BAT_CHRG_DIR		(1 << 2)
> +#define PS_STAT_VBUS_ABOVE_VHOLD	(1 << 3)
> +#define PS_STAT_VBUS_VALID		(1 << 4)
> +#define PS_STAT_VBUS_PRESENT		(1 << 5)
> +
> +#define AXP288_BC_GLOBAL_REG		0x2c
> +#define BC_GLOBAL_RUN			(1 << 0)
> +#define BC_GLOBAL_DET_STAT		(1 << 2)
> +#define BC_GLOBAL_DBP_TOUT		(1 << 3)
> +#define BC_GLOBAL_VLGC_COM_SEL		(1 << 4)
> +#define BC_GLOBAL_DCD_TOUT_MASK		0x60
> +#define BC_GLOBAL_DCD_TOUT_300MS	0x0
> +#define BC_GLOBAL_DCD_TOUT_100MS	0x1
> +#define BC_GLOBAL_DCD_TOUT_500MS	0x2
> +#define BC_GLOBAL_DCD_TOUT_900MS	0x3
> +#define BC_GLOBAL_DCD_DET_SEL		(1 << 7)
> +
> +#define AXP288_BC_VBUS_CNTL_REG		0x2d
> +#define VBUS_CNTL_DPDM_PD_EN		(1 << 4)
> +#define VBUS_CNTL_DPDM_FD_EN		(1 << 5)
> +#define VBUS_CNTL_FIRST_PO_STAT		(1 << 6)
> +
> +#define AXP288_BC_USB_STAT_REG		0x2e
> +#define USB_STAT_BUS_STAT_MASK		0x0f
> +#define USB_STAT_BUS_STAT_OFFSET	0
> +#define USB_STAT_BUS_STAT_ATHD		0x0
> +#define USB_STAT_BUS_STAT_CONN		0x1
> +#define USB_STAT_BUS_STAT_SUSP		0x2
> +#define USB_STAT_BUS_STAT_CONF		0x3
> +#define USB_STAT_USB_SS_MODE		(1 << 4)
> +#define USB_STAT_DEAD_BAT_DET		(1 << 6)
> +#define USB_STAT_DBP_UNCFG		(1 << 7)
> +
> +#define AXP288_BC_DET_STAT_REG		0x2f
> +#define DET_STAT_MASK			0xe0
> +#define DET_STAT_OFFSET			5
> +#define DET_STAT_SDP			0x1
> +#define DET_STAT_CDP			0x2
> +#define DET_STAT_DCP			0x3
> +
> +#define AXP288_PS_BOOT_REASON_REG	0x2
> +
> +#define AXP288_PWRSRC_IRQ_CFG_REG	0x40
> +#define PWRSRC_IRQ_CFG_MASK		0x1c
> +
> +#define AXP288_BC12_IRQ_CFG_REG		0x45
> +#define BC12_IRQ_CFG_MASK		0x2
> +
> +#define AXP288_PWRSRC_INTR_NUM		4
> +
> +#define AXP288_DRV_NAME			"axp288_extcon"
> +
> +#define AXP288_EXTCON_CABLE_SDP		"Slow-charger"
> +#define AXP288_EXTCON_CABLE_CDP		"Charge-downstream"
> +#define AXP288_EXTCON_CABLE_DCP		"Fast-charger"
> +
> +#define EXTCON_GPIO_MUX_SEL_PMIC	0
> +#define EXTCON_GPIO_MUX_SEL_SOC		1
> +
> +enum {
> +	VBUS_FALLING_IRQ = 0,
> +	VBUS_RISING_IRQ,
> +	MV_CHNG_IRQ,
> +	BC_USB_CHNG_IRQ,
> +};
> +
> +static const char *axp288_extcon_cables[] = {
> +	AXP288_EXTCON_CABLE_SDP,
> +	AXP288_EXTCON_CABLE_CDP,
> +	AXP288_EXTCON_CABLE_DCP,
> +	NULL,
> +};
> +
> +struct axp288_extcon_info {
> +	struct platform_device *pdev;
> +	struct regmap *regmap;
> +	struct regmap_irq_chip_data *regmap_irqc;
> +	struct axp288_extcon_pdata *pdata;
> +	int irq[AXP288_PWRSRC_INTR_NUM];
> +	struct extcon_dev *edev;
> +	struct usb_phy *otg;
> +	struct notifier_block extcon_nb;
> +	struct extcon_specific_cable_nb cable;
> +	bool is_sdp;
> +	bool usb_id_short;
> +};
> +
> +static char *pwr_up_down_info[] = {
> +	/* bit 0 */ "Last wake caused by user pressing the power button",
> +	/* bit 2 */ "Last wake caused by a charger insertion",
> +	/* bit 1 */ "Last wake caused by a battery insertion",
> +	/* bit 3 */ "Last wake caused by SOC initiated global reset",
> +	/* bit 4 */ "Last wake caused by cold reset",
> +	/* bit 5 */ "Last shutdown caused by PMIC UVLO threshold",
> +	/* bit 6 */ "Last shutdown caused by SOC initiated cold off",
> +	/* bit 7 */ "Last shutdown caused by user pressing the power button",
> +	NULL,
> +};
> +
> +/*
> + * Decode and log the given "reset source indicator"
> + * register and then clear it.
> + */
> +static void axp288_extcon_log_rsi(struct axp288_extcon_info *info,
> +				char **pwrsrc_rsi_info, int reg)
> +{
> +	char **rsi;
> +	unsigned int val, i, clear_mask = 0;
> +	int ret;
> +
> +	ret = regmap_read(info->regmap, reg, &val);
> +	for (i = 0, rsi = pwrsrc_rsi_info; *rsi; rsi++, i++) {
> +		if (val & BIT(i)) {
> +			dev_dbg(&info->pdev->dev, "%s\n", *rsi);
> +			clear_mask |= BIT(i);
> +		}
> +	}
> +
> +	/* Clear the register value for next reboot (write 1 to clear bit) */
> +	regmap_write(info->regmap, reg, clear_mask);
> +}
> +
> +static int 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->pdev->dev, "vbus status read error\n");
> +		return ret;
> +	}
> +
> +	vbus_attach = (pwr_stat & PS_STAT_VBUS_PRESENT) && !info->usb_id_short;
> +	if (vbus_attach) {
> +		dev_dbg(&info->pdev->dev, "vbus present\n");
> +	} else {
> +		dev_dbg(&info->pdev->dev, "vbus not present\n");
> +		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->pdev->dev, "charger detection not complete!!\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->pdev->dev, "stat:%x, cfg:%x\n", stat, cfg);
> +
> +	chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_OFFSET;
> +	info->is_sdp = false;
> +
> +	if (chrg_type == DET_STAT_SDP) {
> +		dev_dbg(&info->pdev->dev, "sdp cable connecetd\n");
> +		notify_otg = true;
> +		notify_charger = true;
> +		info->is_sdp = true;
> +		cable = AXP288_EXTCON_CABLE_SDP;
> +	} else if (chrg_type == DET_STAT_CDP) {
> +		dev_dbg(&info->pdev->dev, "cdp cable connecetd\n");
> +		notify_otg = true;
> +		notify_charger = true;
> +		cable = AXP288_EXTCON_CABLE_CDP;
> +	} else if (chrg_type == DET_STAT_DCP) {
> +		dev_dbg(&info->pdev->dev, "dcp cable connecetd\n");
> +		notify_charger = true;
> +		cable = AXP288_EXTCON_CABLE_DCP;
> +	} else {
> +		dev_warn(&info->pdev->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 != NULL)
> +			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 = false;
> +		notify_charger = false;
> +	}
> +
> +	return 0;
> +
> +dev_det_ret:
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "BC Mod detection error\n");
> +
> +	return ret;
> +}
> +
> +static irqreturn_t axp288_extcon_isr(int irq, void *data)
> +{
> +	struct axp288_extcon_info *info = data;
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < AXP288_PWRSRC_INTR_NUM; i++) {
> +		if (info->irq[i] == irq)
> +			break;
> +	}
> +
> +	if (i == AXP288_PWRSRC_INTR_NUM) {
> +		dev_warn(&info->pdev->dev, "spurious interrupt!!\n");
> +		return IRQ_NONE;
> +	}
> +
> +	ret = handle_chrg_det_event(info);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error in PWRSRC INT handling\n");
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int axp288_extcon_registration(struct axp288_extcon_info *info)
> +{
> +	int ret;
> +
> +	/* Register with extcon */
> +	info->edev = devm_kzalloc(&info->pdev->dev,
> +				sizeof(struct extcon_dev), GFP_KERNEL);
> +	if (!info->edev)
> +		return -ENOMEM;
> +
> +	info->edev->name = "extcon-axp288";
> +	info->edev->supported_cable = axp288_extcon_cables;
> +	ret = extcon_dev_register(info->edev);
> +	if (ret)
> +		dev_err(&info->pdev->dev, "extcon registration failed!!\n");
> +
> +	return ret;
> +}
> +
> +static inline bool is_usb_host_mode(struct extcon_dev *evdev)
> +{
> +	return !!evdev->state;
> +}
> +
> +static int axp288_handle_extcon_event(struct notifier_block *nb,
> +				   unsigned long event, void *param)
> +{
> +	struct axp288_extcon_info *info =
> +	    container_of(nb, struct axp288_extcon_info, extcon_nb);
> +	struct extcon_dev *edev = param;
> +	int usb_host = is_usb_host_mode(edev);
> +
> +	dev_info(&info->pdev->dev,
> +		"[extcon notification] evt:USB-Host val:%s\n",
> +		usb_host ? "Connected" : "Disconnected");
> +
> +	/*
> +	 * Set usb_id_short flag to avoid running charger detection logic
> +	 * in case usb host.
> +	 */
> +	info->usb_id_short = usb_host;
> +
> +	/*
> +	 * Connect the USB mux to SOC in case of usb host else connect
> +	 * it to PMIC.
> +	 */
> +	if (info->pdata->gpio_mux_cntl != NULL) {
> +		dev_dbg(&info->pdev->dev,
> +			"usb_id_short=%d\n", info->usb_id_short);
> +		if (info->usb_id_short)
> +			gpiod_set_value(info->pdata->gpio_mux_cntl,
> +					EXTCON_GPIO_MUX_SEL_SOC);
> +		else
> +			gpiod_set_value(info->pdata->gpio_mux_cntl,
> +					EXTCON_GPIO_MUX_SEL_PMIC);
> +	}
> +
> +	return NOTIFY_OK;
> +}
> +
> +static int axp288_init_gpio_mux_cntl(struct axp288_extcon_info *info)
> +{
> +	int ret;
> +
> +	ret = gpio_request(desc_to_gpio(info->pdata->gpio_mux_cntl), "USB_MUX");
> +	if (ret < 0) {
> +		dev_err(&info->pdev->dev,
> +			"usb mux gpio request failed:gpio=%d\n",
> +			desc_to_gpio(info->pdata->gpio_mux_cntl));
> +		return ret;
> +	}
> +	gpiod_direction_output(info->pdata->gpio_mux_cntl,
> +					EXTCON_GPIO_MUX_SEL_PMIC);
> +
> +	info->extcon_nb.notifier_call = axp288_handle_extcon_event;
> +	ret = extcon_register_interest(&info->cable, NULL,
> +				"USB-Host", &info->extcon_nb);
> +	if (ret) {
> +		dev_err(&info->pdev->dev, "failed to register extcon notifier\n");
> +		return ret;
> +	}
> +
> +	if (info->cable.edev)
> +		info->usb_id_short =
> +				is_usb_host_mode(info->cable.edev);
> +	if (info->usb_id_short)
> +		gpiod_set_value(info->pdata->gpio_mux_cntl,
> +					EXTCON_GPIO_MUX_SEL_SOC);
> +
> +	return 0;
> +}
> +
> +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;
> +
> +	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
> +	if (!info)
> +		return -ENOMEM;
> +
> +	info->pdev = pdev;
> +	info->regmap = axp20x->regmap;
> +	info->regmap_irqc = axp20x->regmap_irqc;
> +	info->pdata = pdev->dev.platform_data;
> +
> +	if (!info->pdata) {
> +		/* TODO: Try ACPI provided pdata via device properties */
> +		if (!device_property_present(&pdev->dev,
> +					"axp288_extcon_data\n"))
> +			dev_err(&pdev->dev, "no platform data\n");
> +		return -ENODEV;
> +	}
> +	platform_set_drvdata(pdev, info);
> +
> +	axp288_extcon_log_rsi(info, pwr_up_down_info,
> +				AXP288_PS_BOOT_REASON_REG);
> +
> +	/* Register extcon device */
> +	ret = axp288_extcon_registration(info);
> +	if (ret < 0)
> +		goto extcon_reg_failed;
> +
> +	/* Get otg transceiver phy */
> +	info->otg = usb_get_phy(USB_PHY_TYPE_USB2);
> +	if (IS_ERR(info->otg)) {
> +		dev_warn(&info->pdev->dev, "Failed to get otg transceiver!!\n");
> +		ret = PTR_ERR(info->otg);
> +		goto otg_reg_failed;
> +	}
> +
> +	for (i = 0; i < AXP288_PWRSRC_INTR_NUM; 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(&info->pdev->dev,
> +				"regmap_irq get virq failed for IRQ %d: %d\n",
> +				pirq, info->irq[i]);
> +			info->irq[i] = -1;
> +			goto intr_reg_failed;
> +		}
> +		ret = request_threaded_irq(info->irq[i],
> +				NULL, axp288_extcon_isr,
> +				IRQF_ONESHOT, AXP288_DRV_NAME, info);
> +		if (ret) {
> +			dev_err(&pdev->dev, "request_irq fail :%d err:%d\n",
> +							info->irq[i], ret);
> +			goto intr_reg_failed;
> +		}
> +	}
> +
> +	/* Set up gpio control for USB Mux */
> +	if (info->pdata->gpio_mux_cntl != NULL) {
> +		ret = axp288_init_gpio_mux_cntl(info);
> +		if (ret < 0)
> +			goto intr_reg_failed;
> +	}
> +
> +	/* 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 complte 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);
> +
> +	return 0;
> +
> +intr_reg_failed:
> +	for (; i > 0; i--) {
> +		free_irq(info->irq[i - 1], info);
> +		info->irq[i - 1] = -1;
> +	}
> +	usb_put_phy(info->otg);
> +otg_reg_failed:
> +	extcon_dev_unregister(info->edev);
> +extcon_reg_failed:
> +	return ret;
> +}
> +
> +static int axp288_extcon_remove(struct platform_device *pdev)
> +{
> +	struct axp288_extcon_info *info = platform_get_drvdata(pdev);
> +	int i;
> +
> +	for (i = 0; i < AXP288_PWRSRC_INTR_NUM; i++)
> +		free_irq(info->irq[i], info);
> +	usb_put_phy(info->otg);
> +	extcon_dev_unregister(info->edev);
> +	return 0;
> +}
> +
> +static struct platform_driver axp288_extcon_driver = {
> +	.probe = axp288_extcon_probe,
> +	.remove = axp288_extcon_remove,
> +	.driver = {
> +		.name = AXP288_DRV_NAME,
> +	},
> +};
> +module_platform_driver(axp288_extcon_driver);
> +
> +MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
> +MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
> +MODULE_LICENSE("GPL");
> 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
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