From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fI8IH-00066m-7m for barebox@lists.infradead.org; Mon, 14 May 2018 07:53:19 +0000 Date: Mon, 14 May 2018 09:53:04 +0200 From: Sascha Hauer Message-ID: <20180514075304.gxad46n7wfiikgk7@pengutronix.de> References: <20180510152019.9607-1-nikita.yoush@cogentembedded.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20180510152019.9607-1-nikita.yoush@cogentembedded.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH 1/2] clk: add clk-gpio driver To: Nikita Yushchenko Cc: barebox@lists.infradead.org, Chris Healy On Thu, May 10, 2018 at 06:20:18PM +0300, Nikita Yushchenko wrote: > This implements support for gpio-gate-clock device tree nodes, that > define clocks that can be enabled or disabled via GPIO line. > > Signed-off-by: Nikita Yushchenko > --- > drivers/clk/Makefile | 2 +- > drivers/clk/clk-gpio.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 131 insertions(+), 1 deletion(-) > create mode 100644 drivers/clk/clk-gpio.c Applied, thanks Sascha > > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile > index 55ac9535a..cd4026c94 100644 > --- a/drivers/clk/Makefile > +++ b/drivers/clk/Makefile > @@ -1,7 +1,7 @@ > obj-$(CONFIG_COMMON_CLK) += clk.o clk-fixed.o clk-divider.o clk-fixed-factor.o \ > clk-mux.o clk-gate.o clk-composite.o \ > clk-fractional-divider.o clk-conf.o \ > - clk-gate-shared.o > + clk-gate-shared.o clk-gpio.o > obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o > > obj-$(CONFIG_ARCH_MVEBU) += mvebu/ > diff --git a/drivers/clk/clk-gpio.c b/drivers/clk/clk-gpio.c > new file mode 100644 > index 000000000..352c85dfe > --- /dev/null > +++ b/drivers/clk/clk-gpio.c > @@ -0,0 +1,130 @@ > +/* > + * clk-gpio.c - clock that can be enabled and disabled via GPIO output > + * Based on Linux clk support > + * > + * Copyright (c) 2018 Nikita Yushchenko > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct clk_gpio { > + struct clk clk; > + const char *parent; > + int gpio; > +}; > +#define to_clk_gpio(_clk) container_of(_clk, struct clk_gpio, clk) > + > +static int clk_gpio_enable(struct clk *clk) > +{ > + struct clk_gpio *clk_gpio = to_clk_gpio(clk); > + > + gpio_set_active(clk_gpio->gpio, true); > + return 0; > +} > + > +static void clk_gpio_disable(struct clk *clk) > +{ > + struct clk_gpio *clk_gpio = to_clk_gpio(clk); > + > + gpio_set_active(clk_gpio->gpio, false); > +} > + > +static int clk_gpio_is_enabled(struct clk *clk) > +{ > + struct clk_gpio *clk_gpio = to_clk_gpio(clk); > + > + return gpio_is_active(clk_gpio->gpio); > +} > + > +static struct clk_ops clk_gpio_ops = { > + .set_rate = clk_parent_set_rate, > + .round_rate = clk_parent_round_rate, > + .enable = clk_gpio_enable, > + .disable = clk_gpio_disable, > + .is_enabled = clk_gpio_is_enabled, > +}; > + > +static int of_gpio_clk_setup(struct device_node *node) > +{ > + struct clk_gpio *clk_gpio; > + enum of_gpio_flags of_flags; > + unsigned long flags; > + int ret; > + > + clk_gpio = xzalloc(sizeof(*clk_gpio)); > + if (!clk_gpio) > + return -ENOMEM; > + > + clk_gpio->parent = of_clk_get_parent_name(node, 0); > + if (!clk_gpio->parent) { > + ret = -EINVAL; > + goto no_parent; > + } > + > + clk_gpio->clk.ops = &clk_gpio_ops; > + clk_gpio->clk.parent_names = &clk_gpio->parent; > + clk_gpio->clk.num_parents = 1; > + > + clk_gpio->clk.name = node->name; > + of_property_read_string(node, "clock-output-names", > + &clk_gpio->clk.name); > + > + ret = of_get_named_gpio_flags(node, "enable-gpios", 0, > + &of_flags); > + if (ret >= 0 && !gpio_is_valid(ret)) > + ret = -EINVAL; > + if (ret < 0) > + goto no_gpio; > + clk_gpio->gpio = ret; > + > + flags = GPIOF_OUT_INIT_ACTIVE; > + if (of_flags & OF_GPIO_ACTIVE_LOW) > + flags |= GPIOF_ACTIVE_LOW; > + ret = gpio_request_one(clk_gpio->gpio, flags, clk_gpio->clk.name); > + if (ret) > + goto no_request; > + > + ret = clk_register(&clk_gpio->clk); > + if (ret) > + goto no_register; > + > + return of_clk_add_provider(node, of_clk_src_simple_get, &clk_gpio->clk); > + > +no_register: > + gpio_free(clk_gpio->gpio); > +no_request: > +no_gpio: > +no_parent: > + free(clk_gpio); > + return ret; > +} > + > +/* Can't use OF_CLK_DECLARE due to need to run after GPIOcontrollers have > + * registrered */ > + > +static const struct of_device_id clk_gpio_device_id[] = { > + { .compatible = "gpio-gate-clock", .data = of_gpio_clk_setup, }, > + {} > +}; > + > +static int clk_gpio_init(void) > +{ > + return of_clk_init(NULL, clk_gpio_device_id); > +} > +coredevice_initcall(clk_gpio_init); > -- > 2.11.0 > > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox