From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from la-in-x022c.1e100.net ([2a00:1450:4010:c03::22c] helo=mail-la0-x22c.google.com) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1U39KI-0002Sc-Ar for barebox@lists.infradead.org; Wed, 06 Feb 2013 18:02:31 +0000 Received: by mail-la0-f44.google.com with SMTP id eb20so1700693lab.3 for ; Wed, 06 Feb 2013 10:02:27 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: <1359918977-1932-1-git-send-email-antonynpavlov@gmail.com> <20130203211352.GH18068@game.jcrosoft.org> <20130204083759.GB1906@pengutronix.de> <20130205092955.GT1906@pengutronix.de> <20130205101958.GB19322@game.jcrosoft.org> Date: Wed, 6 Feb 2013 22:02:27 +0400 Message-ID: From: Antony Pavlov 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-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [RFC] gpiolib: import gpio_request_array() from linux 3.7 To: Jean-Christophe PLAGNIOL-VILLARD Cc: barebox@lists.infradead.org ping On 5 February 2013 15:02, Antony Pavlov wrote: > On 5 February 2013 14:19, Jean-Christophe PLAGNIOL-VILLARD > wrote: >> On 10:29 Tue 05 Feb , Sascha Hauer wrote: >>> On Tue, Feb 05, 2013 at 10:10:18AM +0400, Antony Pavlov wrote: >>> > On 4 February 2013 12:37, Sascha Hauer wrote: >>> > > On Mon, Feb 04, 2013 at 01:22:39AM +0400, Antony Pavlov wrote: >>> > >> On 4 February 2013 01:13, Jean-Christophe PLAGNIOL-VILLARD >>> > >> wrote: >>> > >> > On 23:16 Sun 03 Feb , Antony Pavlov wrote: >>> > >> >> Also import related functions gpio_request_one() and >>> > >> >> gpio_free_array(). >>> > >> >> >>> > >> >> Signed-off-by: Antony Pavlov >>> > >> >> --- >>> > >> >> drivers/gpio/gpio.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++ >>> > >> >> include/gpio.h | 43 +++++++++++++++++++++++++++++++++ >>> > >> >> 2 files changed, 109 insertions(+) >>> > >> >> >>> > >> >> diff --git a/drivers/gpio/gpio.c b/drivers/gpio/gpio.c >>> > >> >> index d37f5a0..631168d 100644 >>> > >> >> --- a/drivers/gpio/gpio.c >>> > >> >> +++ b/drivers/gpio/gpio.c >>> > >> >> @@ -65,6 +65,72 @@ void gpio_free(unsigned gpio) >>> > >> >> free(gi->label); >>> > >> >> } >>> > >> >> >>> > >> >> +/** >>> > >> >> + * gpio_request_one - request a single GPIO with initial configuration >>> > >> >> + * @gpio: the GPIO number >>> > >> >> + * @flags: GPIO configuration as specified by GPIOF_* >>> > >> >> + * @label: a literal description string of this GPIO >>> > >> >> + */ >>> > >> >> +int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) >>> > >> >> +{ >>> > >> >> + int err; >>> > >> >> + >>> > >> >> + err = gpio_request(gpio, label); >>> > >> >> + if (err) >>> > >> >> + return err; >>> > >> >> + >>> > >> >> + if (flags & GPIOF_DIR_IN) >>> > >> >> + err = gpio_direction_input(gpio); >>> > >> >> + else >>> > >> >> + err = gpio_direction_output(gpio, >>> > >> >> + (flags & GPIOF_INIT_HIGH) ? 1 : 0); >>> > >> >> + >>> > >> >> + if (err) >>> > >> >> + goto free_gpio; >>> > >> >> + >>> > >> >> + return 0; >>> > >> >> + >>> > >> >> +free_gpio: >>> > >> >> + gpio_free(gpio); >>> > >> >> + return err; >>> > >> >> +} >>> > >> >> +EXPORT_SYMBOL(gpio_request_one); >>> > >> >> + >>> > >> >> +/** >>> > >> >> + * gpio_request_array - request multiple GPIOs in a single call >>> > >> >> + * @array: array of the 'struct gpio' >>> > >> >> + * @num: how many GPIOs in the array >>> > >> >> + */ >>> > >> >> +int gpio_request_array(const struct gpio *array, size_t num) >>> > >> >> +{ >>> > >> >> + int i, err; >>> > >> >> + >>> > >> >> + for (i = 0; i < num; i++, array++) { >>> > >> >> + err = gpio_request_one(array->gpio, array->flags, array->label); >>> > >> >> + if (err) >>> > >> >> + goto err_free; >>> > >> >> + } >>> > >> >> + return 0; >>> > >> >> + >>> > >> >> +err_free: >>> > >> >> + while (i--) >>> > >> >> + gpio_free((--array)->gpio); >>> > >> >> + return err; >>> > >> >> +} >>> > >> >> +EXPORT_SYMBOL(gpio_request_array); >>> > >> >> + >>> > >> >> +/** >>> > >> >> + * gpio_free_array - release multiple GPIOs in a single call >>> > >> >> + * @array: array of the 'struct gpio' >>> > >> >> + * @num: how many GPIOs in the array >>> > >> >> + */ >>> > >> >> +void gpio_free_array(const struct gpio *array, size_t num) >>> > >> >> +{ >>> > >> >> + while (num--) >>> > >> >> + gpio_free((array++)->gpio); >>> > >> >> +} >>> > >> >> +EXPORT_SYMBOL(gpio_free_array); >>> > >> >> + >>> > >> >> void gpio_set_value(unsigned gpio, int value) >>> > >> >> { >>> > >> >> struct gpio_info *gi = &gpio_desc[gpio]; >>> > >> >> diff --git a/include/gpio.h b/include/gpio.h >>> > >> >> index eedb980..37c151d 100644 >>> > >> >> --- a/include/gpio.h >>> > >> >> +++ b/include/gpio.h >>> > >> >> @@ -3,6 +3,29 @@ >>> > >> >> >>> > >> >> #include >>> > >> >> >>> > >> >> +/* make these flag values available regardless of GPIO kconfig options */ >>> > >> >> +#define GPIOF_DIR_OUT (0 << 0) >>> > >> >> +#define GPIOF_DIR_IN (1 << 0) >>> > >> >> + >>> > >> >> +#define GPIOF_INIT_LOW (0 << 1) >>> > >> >> +#define GPIOF_INIT_HIGH (1 << 1) >>> > >> >> + >>> > >> >> +#define GPIOF_IN (GPIOF_DIR_IN) >>> > >> >> +#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW) >>> > >> >> +#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH) >>> > >> >> + >>> > >> >> +/** >>> > >> >> + * struct gpio - a structure describing a GPIO with configuration >>> > >> >> + * @gpio: the GPIO number >>> > >> >> + * @flags: GPIO configuration as specified by GPIOF_* >>> > >> >> + * @label: a literal description string of this GPIO >>> > >> >> + */ >>> > >> >> +struct gpio { >>> > >> >> + unsigned gpio; >>> > >> >> + unsigned long flags; >>> > >> >> + const char *label; >>> > >> >> +}; >>> > >> >> + >>> > >> >> #ifndef CONFIG_GPIOLIB >>> > >> >> static inline int gpio_request(unsigned gpio, const char *label) >>> > >> >> { >>> > >> >> @@ -12,9 +35,29 @@ static inline int gpio_request(unsigned gpio, const char *label) >>> > >> >> static inline void gpio_free(unsigned gpio) >>> > >> >> { >>> > >> >> } >>> > >> >> + >>> > >> >> +static inline int gpio_request_one(unsigned gpio, >>> > >> >> + unsigned long flags, const char *label) >>> > >> >> +{ >>> > >> >> + return 0; >>> > >> >> +} >>> > >> >> + >>> > >> >> +static inline int gpio_request_array(const struct gpio *array, size_t num) >>> > >> >> +{ >>> > >> >> + return 0; >>> > >> >> +} >>> > >> > you can not do this >>> > >> > >>> > >> > as if we start to use this in generic driver where gpio_direction_input/output >>> > >> > work >>> > >> > >>> > >> > we will endup with no configuration >>> > >> >>> > >> But now in include/gpio.h we have this: >>> > >> >>> > >> static inline int gpio_request(unsigned gpio, const char *label) >>> > >> { >>> > >> return 0; >>> > >> } >>> > >> >>> > >> Can you explain the difference? >>> > > >>> > > gpio_request is not implemented without gpiolib, still you have to >>> > > configure the direction and value. >>> > >>> > Can we use this functions only if gpiolib is enabled? >>> > Can we skip the function's definiton in the non-gpio situation? >>> >>> Sounds fine. We should get rid of the !gpiolib drivers anyway, maybe >>> this adds some motivation. >> >> until every driver are swith to gpiolib NACK as if we switch any generic >> driver to this as leds, gpio-keys, i2c-gpio etc... we break board support >> siliently > > but leds, gpio-keys, i2c-gpio etc don't use > gpio_request_one()-related functions. > If we ristrict the usage of gpio_request_one()-related functions (use > it only in board code for gpiolib-enabled machines) > we can avoid mentioned problems. > > -- > Best regards, > Antony Pavlov -- Best regards, Antony Pavlov _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox