From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from 19.mo4.mail-out.ovh.net ([87.98.179.66] helo=mo4.mail-out.ovh.net) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TSp1T-0006OX-3w for barebox@lists.infradead.org; Mon, 29 Oct 2012 13:04:57 +0000 Received: from mail172.ha.ovh.net (b7.ovh.net [213.186.33.57]) by mo4.mail-out.ovh.net (Postfix) with SMTP id AF73E104E94D for ; Mon, 29 Oct 2012 14:11:56 +0100 (CET) From: Jean-Christophe PLAGNIOL-VILLARD Date: Mon, 29 Oct 2012 14:02:37 +0100 Message-Id: <1351515759-25548-3-git-send-email-plagnioj@jcrosoft.com> In-Reply-To: <1351515759-25548-1-git-send-email-plagnioj@jcrosoft.com> References: <20121029124609.GG28904@game.jcrosoft.org> <1351515759-25548-1-git-send-email-plagnioj@jcrosoft.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 3/5] 1-wire: add gpio bus To: barebox@lists.infradead.org Based on linux implementation. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD --- drivers/w1/masters/Kconfig | 7 +++ drivers/w1/masters/Makefile | 1 + drivers/w1/masters/w1-gpio.c | 116 ++++++++++++++++++++++++++++++++++++++++++ include/linux/w1-gpio.h | 25 +++++++++ 4 files changed, 149 insertions(+) create mode 100644 drivers/w1/masters/w1-gpio.c create mode 100644 include/linux/w1-gpio.h diff --git a/drivers/w1/masters/Kconfig b/drivers/w1/masters/Kconfig index 86aa8df..e429c14 100644 --- a/drivers/w1/masters/Kconfig +++ b/drivers/w1/masters/Kconfig @@ -4,4 +4,11 @@ menu "1-wire Bus Masters" +config W1_MASTER_GPIO + bool "GPIO 1-wire busmaster" + depends on GENERIC_GPIO + help + Say Y here if you want to communicate with your 1-wire devices using + GPIO pins. This driver uses the GPIO API to control the wire. + endmenu diff --git a/drivers/w1/masters/Makefile b/drivers/w1/masters/Makefile index ed1b9d9..84b35bb 100644 --- a/drivers/w1/masters/Makefile +++ b/drivers/w1/masters/Makefile @@ -2,3 +2,4 @@ # Makefile for 1-wire bus master drivers. # +obj-$(CONFIG_W1_MASTER_GPIO) += w1-gpio.o diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c new file mode 100644 index 0000000..0a3794d --- /dev/null +++ b/drivers/w1/masters/w1-gpio.c @@ -0,0 +1,116 @@ +/* + * w1-gpio - GPIO w1 bus master driver + * + * Copyright (C) 2007 Ville Syrjala + * Copyright (c) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * 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 +#include +#include +#include +#include +#include +#include + +#include "../w1.h" + +static void w1_gpio_write_bit_dir(struct w1_bus *bus, u8 bit) +{ + struct w1_gpio_platform_data *pdata = bus->data; + + if (bit) + gpio_direction_input(pdata->pin); + else + gpio_direction_output(pdata->pin, 0); +} + +static void w1_gpio_write_bit_val(struct w1_bus *bus, u8 bit) +{ + struct w1_gpio_platform_data *pdata = bus->data; + + gpio_set_value(pdata->pin, bit); +} + +static u8 w1_gpio_read_bit(struct w1_bus *bus) +{ + struct w1_gpio_platform_data *pdata = bus->data; + + return gpio_get_value(pdata->pin) ? 1 : 0; +} + +static int __init w1_gpio_probe(struct device_d *dev) +{ + struct w1_bus *master; + struct w1_gpio_platform_data *pdata; + int err; + + pdata = dev->platform_data; + + if (!pdata) + return -ENXIO; + + master = xzalloc(sizeof(struct w1_bus)); + + err = gpio_request(pdata->pin, "w1"); + if (err) + goto free_master; + + if (gpio_is_valid(pdata->ext_pullup_enable_pin)) { + err = gpio_request(pdata->pin, "w1 pullup"); + if (err < 0) + goto free_gpio; + + gpio_direction_output(pdata->pin, 0); + } + + master->data = pdata; + master->read_bit = w1_gpio_read_bit; + + if (pdata->is_open_drain) { + gpio_direction_output(pdata->pin, 1); + master->write_bit = w1_gpio_write_bit_val; + } else { + gpio_direction_input(pdata->pin); + master->write_bit = w1_gpio_write_bit_dir; + } + + master->parent = dev; + + err = w1_bus_register(master); + if (err) + goto free_gpio_ext_pu; + + if (pdata->enable_external_pullup) + pdata->enable_external_pullup(1); + + if (gpio_is_valid(pdata->ext_pullup_enable_pin)) + gpio_set_value(pdata->ext_pullup_enable_pin, 1); + + return 0; + + free_gpio_ext_pu: + if (gpio_is_valid(pdata->ext_pullup_enable_pin)) + gpio_free(pdata->ext_pullup_enable_pin); + free_gpio: + gpio_free(pdata->pin); + free_master: + kfree(master); + + return err; +} + +static struct driver_d w1_gpio_driver = { + .name = "w1-gpio", + .probe = w1_gpio_probe, +}; + +static int __init w1_gpio_init(void) +{ + return platform_driver_register(&w1_gpio_driver); +} +device_initcall(w1_gpio_init); diff --git a/include/linux/w1-gpio.h b/include/linux/w1-gpio.h new file mode 100644 index 0000000..065e3ae --- /dev/null +++ b/include/linux/w1-gpio.h @@ -0,0 +1,25 @@ +/* + * w1-gpio interface to platform code + * + * Copyright (C) 2007 Ville Syrjala + * + * 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. + */ +#ifndef _LINUX_W1_GPIO_H +#define _LINUX_W1_GPIO_H + +/** + * struct w1_gpio_platform_data - Platform-dependent data for w1-gpio + * @pin: GPIO pin to use + * @is_open_drain: GPIO pin is configured as open drain + */ +struct w1_gpio_platform_data { + unsigned int pin; + unsigned int is_open_drain:1; + void (*enable_external_pullup)(int enable); + unsigned int ext_pullup_enable_pin; +}; + +#endif /* _LINUX_W1_GPIO_H */ -- 1.7.10.4 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox