Re: [PATCH v1 2/2] extcon: mrfld: Introduce extcon driver for Basin Cove PMIC

From: Andy Shevchenko
Date: Mon Mar 18 2019 - 06:11:15 EST


On Mon, Mar 18, 2019 at 12:52:25PM +0300, Andy Shevchenko wrote:
> TBD

Oops.
I though I have written it already.

I will wait for other comments today and sent a new version with commit message
filled as follows:

On Intel Merrifield the Basin Cove PMIC provides a feature to detect
the USB connection type. This driver utilizes the feature in order to support
the USB dual role detection.

>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> drivers/extcon/Kconfig | 7 +
> drivers/extcon/Makefile | 1 +
> drivers/extcon/extcon-intel-mrfld.c | 256 ++++++++++++++++++++++++++++
> 3 files changed, 264 insertions(+)
> create mode 100644 drivers/extcon/extcon-intel-mrfld.c
>
> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> index 8e17149655f0..75349c6cc89e 100644
> --- a/drivers/extcon/Kconfig
> +++ b/drivers/extcon/Kconfig
> @@ -60,6 +60,13 @@ config EXTCON_INTEL_CHT_WC
> Say Y here to enable extcon support for charger detection / control
> on the Intel Cherrytrail Whiskey Cove PMIC.
>
> +config EXTCON_INTEL_MRFLD

> + tristate "Intel MErrifield Basin Cove PMIC extcon driver"

ME -> Me (will be fixed)

> + depends on INTEL_SOC_PMIC_MRFLD
> + help
> + Say Y here to enable extcon support for charger detection / control
> + on the Intel Merrifiel Basin Cove PMIC.
> +
> config EXTCON_MAX14577
> tristate "Maxim MAX14577/77836 EXTCON Support"
> depends on MFD_MAX14577
> diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
> index 261ce4cfe209..d3941a735df3 100644
> --- a/drivers/extcon/Makefile
> +++ b/drivers/extcon/Makefile
> @@ -11,6 +11,7 @@ obj-$(CONFIG_EXTCON_AXP288) += extcon-axp288.o
> obj-$(CONFIG_EXTCON_GPIO) += extcon-gpio.o
> obj-$(CONFIG_EXTCON_INTEL_INT3496) += extcon-intel-int3496.o
> obj-$(CONFIG_EXTCON_INTEL_CHT_WC) += extcon-intel-cht-wc.o
> +obj-$(CONFIG_EXTCON_INTEL_MRFLD) += extcon-intel-mrfld.o
> obj-$(CONFIG_EXTCON_MAX14577) += extcon-max14577.o
> obj-$(CONFIG_EXTCON_MAX3355) += extcon-max3355.o
> obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o
> diff --git a/drivers/extcon/extcon-intel-mrfld.c b/drivers/extcon/extcon-intel-mrfld.c
> new file mode 100644
> index 000000000000..d45db4975b5f
> --- /dev/null
> +++ b/drivers/extcon/extcon-intel-mrfld.c
> @@ -0,0 +1,256 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Extcon driver for Basin Cove PMIC
> + *
> + * Copyright (c) 2018, Intel Corporation.

2019 I suppose :-)

> + * Author: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> + */
> +
> +#include <linux/extcon-provider.h>
> +#include <linux/interrupt.h>
> +#include <linux/mfd/intel_soc_pmic.h>
> +#include <linux/mfd/intel_soc_pmic_mrfld.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#include "extcon-intel.h"
> +
> +#define BCOVE_USBIDCTRL 0x19
> +#define BCOVE_USBIDCTRL_ID BIT(0)
> +#define BCOVE_USBIDCTRL_ACA BIT(1)
> +#define BCOVE_USBIDCTRL_ALL (BCOVE_USBIDCTRL_ID | BCOVE_USBIDCTRL_ACA)
> +
> +#define BCOVE_USBIDSTS 0x1a
> +#define BCOVE_USBIDSTS_GND BIT(0)
> +#define BCOVE_USBIDSTS_RARBRC_MASK GENMASK(2, 1)
> +#define BCOVE_USBIDSTS_RARBRC_SHIFT 1
> +#define BCOVE_USBIDSTS_NO_ACA 0
> +#define BCOVE_USBIDSTS_R_ID_A 1
> +#define BCOVE_USBIDSTS_R_ID_B 2
> +#define BCOVE_USBIDSTS_R_ID_C 3
> +#define BCOVE_USBIDSTS_FLOAT BIT(3)
> +#define BCOVE_USBIDSTS_SHORT BIT(4)
> +
> +#define BCOVE_CHGRIRQ_ALL (BCOVE_CHGRIRQ_VBUSDET | BCOVE_CHGRIRQ_DCDET | \
> + BCOVE_CHGRIRQ_BATTDET | BCOVE_CHGRIRQ_USBIDDET)
> +
> +#define BCOVE_CHGRCTRL0 0x4b
> +#define BCOVE_CHGRCTRL0_CHGRRESET BIT(0)
> +#define BCOVE_CHGRCTRL0_EMRGCHREN BIT(1)
> +#define BCOVE_CHGRCTRL0_EXTCHRDIS BIT(2)
> +#define BCOVE_CHGRCTRL0_SWCONTROL BIT(3)
> +#define BCOVE_CHGRCTRL0_TTLCK BIT(4)
> +#define BCOVE_CHGRCTRL0_BIT_5 BIT(5)
> +#define BCOVE_CHGRCTRL0_BIT_6 BIT(6)
> +#define BCOVE_CHGRCTRL0_CHR_WDT_NOKICK BIT(7)
> +
> +struct mrfld_extcon_data {
> + struct device *dev;
> + struct regmap *regmap;
> + struct extcon_dev *edev;
> + unsigned int status;
> + unsigned int id;
> +};
> +
> +static const unsigned int mrfld_extcon_cable[] = {
> + EXTCON_USB,
> + EXTCON_USB_HOST,
> + EXTCON_CHG_USB_SDP,
> + EXTCON_CHG_USB_CDP,
> + EXTCON_CHG_USB_DCP,
> + EXTCON_CHG_USB_ACA,
> + EXTCON_NONE,
> +};
> +
> +static int mrfld_extcon_clear(struct mrfld_extcon_data *data, unsigned int reg,
> + unsigned int mask)
> +{
> + return regmap_update_bits(data->regmap, reg, mask, 0x00);
> +}
> +
> +static int mrfld_extcon_set(struct mrfld_extcon_data *data, unsigned int reg,
> + unsigned int mask)
> +{
> + return regmap_update_bits(data->regmap, reg, mask, 0xff);
> +}
> +
> +static int mrfld_extcon_get_id(struct mrfld_extcon_data *data)
> +{
> + struct regmap *regmap = data->regmap;
> + unsigned int id;
> + bool ground;
> + int ret;
> +
> + ret = regmap_read(regmap, BCOVE_USBIDSTS, &id);
> + if (ret)
> + return ret;
> +
> + if (id & BCOVE_USBIDSTS_FLOAT)
> + return INTEL_USB_ID_FLOAT;
> +
> + switch ((id & BCOVE_USBIDSTS_RARBRC_MASK) >> BCOVE_USBIDSTS_RARBRC_SHIFT) {
> + case BCOVE_USBIDSTS_R_ID_A:
> + return INTEL_USB_RID_A;
> + case BCOVE_USBIDSTS_R_ID_B:
> + return INTEL_USB_RID_B;
> + case BCOVE_USBIDSTS_R_ID_C:
> + return INTEL_USB_RID_C;
> + }
> +
> + /*
> + * PMIC A0 reports USBIDSTS_GND = 1 for ID_GND,
> + * but PMIC B0 reports USBIDSTS_GND = 0 for ID_GND.
> + * Thus we must check this bit at last.
> + */
> + ground = id & BCOVE_USBIDSTS_GND;
> + switch ('A' + BCOVE_MAJOR(data->id)) {
> + case 'A':
> + return ground ? INTEL_USB_ID_GND : INTEL_USB_ID_FLOAT;
> + case 'B':
> + return ground ? INTEL_USB_ID_FLOAT : INTEL_USB_ID_GND;
> + }
> +
> + /* Unknown or unsupported type */
> + return INTEL_USB_ID_FLOAT;
> +}
> +
> +static int mrfld_extcon_role_detect(struct mrfld_extcon_data *data)
> +{
> + unsigned int id;
> + bool usb_host;
> + int ret;
> +
> + ret = mrfld_extcon_get_id(data);
> + if (ret < 0)
> + return ret;
> +
> + id = ret;
> +
> + usb_host = (id == INTEL_USB_ID_GND) || (id == INTEL_USB_RID_A);
> + extcon_set_state_sync(data->edev, EXTCON_USB_HOST, usb_host);
> +
> + return 0;
> +}
> +
> +static int mrfld_extcon_cable_detect(struct mrfld_extcon_data *data)
> +{
> + struct regmap *regmap = data->regmap;
> + unsigned int status;
> + int ret;
> +
> + /*
> + * It seems SCU firmware clears the content of BCOVE_CHGRIRQ1
> + * and makes it useless for OS. Instead we compare a previously
> + * stored status to the current one, provided by BCOVE_SCHGRIRQ1.
> + */
> + ret = regmap_read(regmap, BCOVE_SCHGRIRQ1, &status);
> + if (ret)
> + return ret;
> +
> + if (!(status ^ data->status))
> + return -ENODATA;
> +
> + if ((status ^ data->status) & BCOVE_CHGRIRQ_USBIDDET)
> + ret = mrfld_extcon_role_detect(data);
> +
> + data->status = status;
> + return ret;
> +}
> +
> +static irqreturn_t mrfld_extcon_interrupt(int irq, void *dev_id)
> +{
> + struct mrfld_extcon_data *data = dev_id;
> + int ret;
> +
> + ret = mrfld_extcon_cable_detect(data);
> +
> + mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
> +
> + return ret ? IRQ_NONE: IRQ_HANDLED;
> +}
> +
> +static int mrfld_extcon_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct intel_soc_pmic *pmic = dev_get_drvdata(dev->parent);
> + struct regmap *regmap = pmic->regmap;
> + struct mrfld_extcon_data *data;
> + unsigned int id;
> + int irq, ret;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0)
> + return irq;
> +
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->dev = dev;
> + data->regmap = regmap;
> +
> + data->edev = devm_extcon_dev_allocate(dev, mrfld_extcon_cable);
> + if (IS_ERR(data->edev))
> + return -ENOMEM;
> +
> + ret = devm_extcon_dev_register(dev, data->edev);
> + if (ret < 0) {
> + dev_err(dev, "can't register extcon device: %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_request_threaded_irq(dev, irq, NULL, mrfld_extcon_interrupt,
> + IRQF_ONESHOT | IRQF_SHARED, pdev->name,
> + data);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(regmap, BCOVE_ID, &id);
> + if (ret)
> + return ret;
> +
> + data->id = id;
> +
> + mrfld_extcon_set(data, BCOVE_CHGRCTRL0, BCOVE_CHGRCTRL0_SWCONTROL);
> +
> + /* Get initial state */
> + mrfld_extcon_role_detect(data);
> +
> + mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
> + mrfld_extcon_clear(data, BCOVE_MCHGRIRQ1, BCOVE_CHGRIRQ_ALL);
> +
> + mrfld_extcon_set(data, BCOVE_USBIDCTRL, BCOVE_USBIDCTRL_ALL);
> +
> + platform_set_drvdata(pdev, data);
> + return 0;
> +}
> +
> +static int mrfld_extcon_remove(struct platform_device *pdev)
> +{
> + struct mrfld_extcon_data *data = platform_get_drvdata(pdev);
> +
> + mrfld_extcon_clear(data, BCOVE_CHGRCTRL0, BCOVE_CHGRCTRL0_SWCONTROL);
> + return 0;
> +}
> +
> +static const struct platform_device_id mrfld_extcon_id_table[] = {
> + { .name = "mrfld_bcove_extcon" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(platform, mrfld_extcon_id_table);
> +
> +static struct platform_driver mrfld_extcon_driver = {
> + .driver = {
> + .name = KBUILD_MODNAME,
> + },
> + .probe = mrfld_extcon_probe,
> + .remove = mrfld_extcon_remove,
> + .id_table = mrfld_extcon_id_table,
> +};
> +module_platform_driver(mrfld_extcon_driver);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Extcon driver for Basin Cove PMIC");
> +MODULE_LICENSE("GPL v2");
> --
> 2.20.1
>

--
With Best Regards,
Andy Shevchenko