On 06/15/2014 07:42 PM, George Cherian wrote:
This is the driver for the USB ID pin detection. This driver handles only the USB ID pin changes generated by cable insertion/removal. Signed-off-by: George Cherian <george.cherian@xxxxxx>
Hi George, Curious: Why can't you use extcon-gpio ? Also, I thought that Linux specific bindings would be unacceptable. "ti,dra7xx-extcon" looks very linux specific to me. Did the rules change ? Thanks, Guenter
--- .../devicetree/bindings/extcon/extcon-dra7xx.txt | 15 ++ drivers/extcon/Kconfig | 5 + drivers/extcon/Makefile | 1 + drivers/extcon/extcon-dra7xx.c | 164 +++++++++++++++++++++ 4 files changed, 185 insertions(+) create mode 100644 Documentation/devicetree/bindings/extcon/extcon-dra7xx.txt create mode 100644 drivers/extcon/extcon-dra7xx.c diff --git a/Documentation/devicetree/bindings/extcon/extcon-dra7xx.txt b/Documentation/devicetree/bindings/extcon/extcon-dra7xx.txt new file mode 100644 index 0000000..69c3804 --- /dev/null +++ b/Documentation/devicetree/bindings/extcon/extcon-dra7xx.txt @@ -0,0 +1,15 @@ +EXTCON FOR DRA7xx USB + +Required Properties: + - compatible : Should be "ti,dra7xx-extcon" + - gpios : specifies the gpio pin used for ID pin detection. + + +Please refer to ../gpio/gpio.txt for details of the common GPIO bindings + +Example: + + dra7xx_extcon { + compatible = "ti,dra7xx-extcon"; + gpios = <&gpio21 1 0>; + }; diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig index aebde48..1481b7f 100644 --- a/drivers/extcon/Kconfig +++ b/drivers/extcon/Kconfig @@ -70,4 +70,9 @@ config EXTCON_PALMAS Say Y here to enable support for USB peripheral and USB host detection by palmas usb. +config EXTCON_DRA7XX + tristate "DRA7xx USB ID detection EXTCON support" + help + Say Y here to enable support for USB ID detection for DRA7xx. + endif # MULTISTATE_SWITCH diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile index bf7861e..b5f7cac 100644 --- a/drivers/extcon/Makefile +++ b/drivers/extcon/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o obj-$(CONFIG_EXTCON_MAX8997) += extcon-max8997.o obj-$(CONFIG_EXTCON_ARIZONA) += extcon-arizona.o obj-$(CONFIG_EXTCON_PALMAS) += extcon-palmas.o +obj-$(CONFIG_EXTCON_DRA7XX) += extcon-dra7xx.o diff --git a/drivers/extcon/extcon-dra7xx.c b/drivers/extcon/extcon-dra7xx.c new file mode 100644 index 0000000..2f80509 --- /dev/null +++ b/drivers/extcon/extcon-dra7xx.c @@ -0,0 +1,164 @@ +/* + * DRA7xx-Extcon USB ID pin detection driver + * + * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.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. + * + * Author: George Cherian <george.cherian@xxxxxx> + * + * 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/err.h> +#include <linux/extcon.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +struct dra7xx_extcon { + struct device *dev; + struct extcon_dev edev; + + int id_gpio; + int id_irq; +}; + +static const char *dra7xx_extcon_cable[] = { + [1] = "USB-HOST", + NULL, +}; + +#define ID_GND 0 + +static irqreturn_t id_irq_handler(int irq, void *data) +{ + struct dra7xx_extcon *dra7xx_extcon = (struct dra7xx_extcon *)data; + int id_current; + + id_current = gpio_get_value_cansleep(dra7xx_extcon->id_gpio); + if (id_current == ID_GND) + extcon_set_cable_state(&dra7xx_extcon->edev, "USB-HOST", true); + else + extcon_set_cable_state(&dra7xx_extcon->edev, "USB-HOST", false); + + return IRQ_HANDLED; +} + +static void dra7xx_extcon_set_initial_state(struct dra7xx_extcon *dra7xx_extcon) +{ + int id_current; + + id_current = gpio_get_value_cansleep(dra7xx_extcon->id_gpio); + if (id_current == ID_GND) + extcon_set_cable_state(&dra7xx_extcon->edev, + "USB-HOST", true); + else + extcon_set_cable_state(&dra7xx_extcon->edev, + "USB-HOST", false); +} + +static int dra7xx_extcon_request_irq(struct dra7xx_extcon *dra7xx_extcon) +{ + int ret; + + ret = devm_request_threaded_irq(dra7xx_extcon->dev, + dra7xx_extcon->id_irq, + NULL, id_irq_handler, + IRQF_ONESHOT | IRQF_TRIGGER_FALLING, + dev_name(dra7xx_extcon->dev), + (void *)dra7xx_extcon); + if (ret) { + dev_err(dra7xx_extcon->dev, "failed to request id irq #%d\n", + dra7xx_extcon->id_irq); + return ret; + } + return ret; +} + +static int dra7xx_extcon_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct dra7xx_extcon *dra7xx_extcon; + int ret, gpio; + + dra7xx_extcon = devm_kzalloc(&pdev->dev, sizeof(*dra7xx_extcon), + GFP_KERNEL); + if (!dra7xx_extcon) + return -ENOMEM; + + dra7xx_extcon->dev = &pdev->dev; + + platform_set_drvdata(pdev, dra7xx_extcon); + + dra7xx_extcon->edev.supported_cable = dra7xx_extcon_cable; + + gpio = of_get_gpio(node, 0); + if (gpio_is_valid(gpio)) { + dra7xx_extcon->id_gpio = gpio; + ret = devm_gpio_request(&pdev->dev, dra7xx_extcon->id_gpio, + "id_gpio"); + if (ret) + return ret; + + dra7xx_extcon->id_irq = gpio_to_irq(dra7xx_extcon->id_gpio); + } else { + dev_err(&pdev->dev, "failed to get id gpio\n"); + return -EPROBE_DEFER; + } + + ret = dra7xx_extcon_request_irq(dra7xx_extcon); + if (ret) + return ret; + + ret = extcon_dev_register(&dra7xx_extcon->edev); + if (ret) { + dev_err(&pdev->dev, "failed to register extcon device\n"); + return ret; + } + + dra7xx_extcon_set_initial_state(dra7xx_extcon); + + return 0; +} + +static int dra7xx_extcon_remove(struct platform_device *pdev) +{ + struct dra7xx_extcon *dra7xx_extcon = platform_get_drvdata(pdev); + + extcon_dev_unregister(&dra7xx_extcon->edev); + return 0; +} + +static struct of_device_id of_dra7xx_extcon_match_tbl[] = { + { .compatible = "ti,dra7xx-extcon", }, + { /* end */ } +}; + +static struct platform_driver dra7xx_extcon_driver = { + .probe = dra7xx_extcon_probe, + .remove = dra7xx_extcon_remove, + .driver = { + .name = "dra7xx-extcon", + .of_match_table = of_dra7xx_extcon_match_tbl, + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(dra7xx_extcon_driver); + +MODULE_ALIAS("platform:extcon-dra7xx"); +MODULE_AUTHOR("George Cherian <george.cherian@xxxxxx>"); +MODULE_DESCRIPTION("USB ID pin detection driver for DRA7xx"); +MODULE_LICENSE("GPL"); +MODULE_DEVICE_TABLE(of, of_dra7xx_extcon_match_tbl);
-- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html