From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick Delaunay Date: Tue, 26 Nov 2019 09:49:05 +0100 Subject: [U-Boot] [PATCH v2 08/14] gpio: add ops for configuration with dir flags In-Reply-To: <20191126084911.19761-1-patrick.delaunay@st.com> References: <20191126084911.19761-1-patrick.delaunay@st.com> Message-ID: <20191126084911.19761-9-patrick.delaunay@st.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de This commit manages the dir flags that can be used in gpio specifiers to indicate if a pull-up resistor or pull-down resistor should be enabled for output gpio (GPIO_PULL_UP, GPIO_PULL_DOWN) and the Open Drain/Open Source configuration for input gpio (GPIO_OPEN_DRAIN, GPIO_OPEN_SOURCE). These flags are already supported in Linux kernel in gpiolib; this patch provides the same support in U-Boot. The dir flags are managed in gpio drivers with two optional ops in gpio uclass: set_dir_flags and get_dir_flags. - ops set_dir_flags() set the direction and configuration of each GPIO with a only call to dm_gpio_set_dir_flags() / dm_gpio_set_dir() and respecting the configuration provided by device tree (saved in desc->flags). - ops get_dir_flags() return dynamically the current gpio configuration, it is used by the new API dm_gpio_get_dir_flags(). When these optional ops are absent, the gpio uclass use the mandatory ops (direction_output, direction_input, get_value) and desc->flags to manage only the main dir flags: - GPIOD_IS_IN - GPIOD_IS_OUT - GPIOD_IS_OUT_ACTIVE - GPIOD_ACTIVE_LOW Signed-off-by: Patrick Delaunay --- Changes in v2: - change the proposed ops for pin config to set_dir_flags/get_dir_flags - reused the existing API dm_gpio_set_dir_flags/dm_gpio_set_dir - add a new API dm_gpio_get_dir_flags drivers/gpio/gpio-uclass.c | 157 +++++++++++++++++++++++++++++++------ include/asm-generic/gpio.h | 65 +++++++++++++-- 2 files changed, 192 insertions(+), 30 deletions(-) diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 0870458e96..241293f4b4 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -140,8 +140,27 @@ int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc, if (args->args_count < 2) return 0; + desc->flags = 0; if (args->args[1] & GPIO_ACTIVE_LOW) - desc->flags = GPIOD_ACTIVE_LOW; + desc->flags |= GPIOD_ACTIVE_LOW; + + /* + * need to test 2 bits for gpio output binding: + * OPEN_DRAIN (0x6) = SINGLE_ENDED (0x2) | LINE_OPEN_DRAIN (0x4) + * OPEN_SOURCE (0x2) = SINGLE_ENDED (0x2) | LINE_OPEN_SOURCE (0x0) + */ + if (args->args[1] & GPIO_SINGLE_ENDED) { + if (args->args[1] & GPIO_LINE_OPEN_DRAIN) + desc->flags |= GPIOD_OPEN_DRAIN; + else + desc->flags |= GPIOD_OPEN_SOURCE; + } + + if (args->args[1] & GPIO_PULL_UP) + desc->flags |= GPIOD_PULL_UP; + + if (args->args[1] & GPIO_PULL_DOWN) + desc->flags |= GPIOD_PULL_DOWN; return 0; } @@ -476,18 +495,24 @@ int gpio_direction_output(unsigned gpio, int value) desc.offset, value); } -int dm_gpio_get_value(const struct gpio_desc *desc) +static int _gpio_get_value(const struct gpio_desc *desc) { int value; + + value = gpio_get_ops(desc->dev)->get_value(desc->dev, desc->offset); + + return desc->flags & GPIOD_ACTIVE_LOW ? !value : value; +} + +int dm_gpio_get_value(const struct gpio_desc *desc) +{ int ret; ret = check_reserved(desc, "get_value"); if (ret) return ret; - value = gpio_get_ops(desc->dev)->get_value(desc->dev, desc->offset); - - return desc->flags & GPIOD_ACTIVE_LOW ? !value : value; + return _gpio_get_value(desc); } int dm_gpio_set_value(const struct gpio_desc *desc, int value) @@ -504,39 +529,119 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value) return 0; } -int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags) +/* check dir flags invalid configuration */ +static int check_dir_flags(ulong flags) +{ + if ((flags & GPIOD_IS_OUT) && (flags & GPIOD_IS_IN)) + return -EINVAL; + + if ((flags & GPIOD_PULL_UP) && (flags & GPIOD_PULL_DOWN)) + return -EINVAL; + + if ((flags & GPIOD_OPEN_DRAIN) && (flags & GPIOD_OPEN_SOURCE)) + return -EINVAL; + + return 0; +} + +static int _dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags) { struct udevice *dev = desc->dev; struct dm_gpio_ops *ops = gpio_get_ops(dev); + struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); int ret; - ret = check_reserved(desc, "set_dir"); - if (ret) - return ret; + ret = check_dir_flags(flags); + if (ret) { + dev_err(dev, + "%s error: set_dir_flags for gpio %s%d has invalid dir flags 0x%lx\n", + desc->dev->name, + uc_priv->bank_name ? uc_priv->bank_name : "", + desc->offset, flags); - if (flags & GPIOD_IS_OUT) { - int value = flags & GPIOD_IS_OUT_ACTIVE ? 1 : 0; + return ret; + } - if (flags & GPIOD_ACTIVE_LOW) - value = !value; - ret = ops->direction_output(dev, desc->offset, value); - } else if (flags & GPIOD_IS_IN) { - ret = ops->direction_input(dev, desc->offset); + /* GPIOD_ are directly managed by driver in set_dir_flags*/ + if (ops->set_dir_flags) { + ret = ops->set_dir_flags(dev, desc->offset, flags); + } else { + if (flags & GPIOD_IS_OUT) { + ret = ops->direction_output(dev, desc->offset, + GPIOD_FLAGS_OUTPUT(flags)); + } else if (flags & GPIOD_IS_IN) { + ret = ops->direction_input(dev, desc->offset); + } } + + return ret; +} + +int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags) +{ + int ret; + + ret = check_reserved(desc, "set_dir_flags"); if (ret) return ret; - /* - * Update desc->flags here, so that GPIO_ACTIVE_LOW is honoured in - * futures - */ - desc->flags = flags; - return 0; + /* combine the requested flags (for IN/OUT) and the descriptor flags */ + flags |= desc->flags; + ret = _dm_gpio_set_dir_flags(desc, flags); + + /* update the descriptor flags */ + if (ret) + desc->flags = flags; + + return ret; } int dm_gpio_set_dir(struct gpio_desc *desc) { - return dm_gpio_set_dir_flags(desc, desc->flags); + int ret; + + ret = check_reserved(desc, "set_dir"); + if (ret) + return ret; + + return _dm_gpio_set_dir_flags(desc, desc->flags); +} + +int dm_gpio_get_dir_flags(struct gpio_desc *desc, ulong *flags) +{ + struct udevice *dev = desc->dev; + struct dm_gpio_ops *ops = gpio_get_ops(dev); + int ret, value; + ulong dir_flags; + + ret = check_reserved(desc, "get_dir_flags"); + if (ret) + return ret; + + /* GPIOD_ are directly provided by driver except GPIOD_ACTIVE_LOW*/ + if (ops->get_dir_flags) { + ret = ops->get_dir_flags(dev, desc->offset, &dir_flags); + if (ret) + return ret; + + /* GPIOD_ACTIVE_LOW is saved in desc->flags */ + value = dir_flags & GPIOD_IS_OUT_ACTIVE ? 1 : 0; + if (desc->flags & GPIOD_ACTIVE_LOW) + value = !value; + dir_flags &= ~(GPIOD_ACTIVE_LOW | GPIOD_IS_OUT_ACTIVE); + dir_flags |= (desc->flags & GPIOD_ACTIVE_LOW); + if (value) + dir_flags |= GPIOD_IS_OUT_ACTIVE; + } else { + dir_flags = desc->flags; + /* only GPIOD_IS_OUT_ACTIVE is provided by uclass */ + dir_flags &= ~GPIOD_IS_OUT_ACTIVE; + if ((desc->flags & GPIOD_IS_OUT) && _gpio_get_value(desc)) + dir_flags |= GPIOD_IS_OUT_ACTIVE; + } + *flags = dir_flags; + + return 0; } /** @@ -809,7 +914,7 @@ static int gpio_request_tail(int ret, const char *nodename, debug("%s: dm_gpio_requestf failed\n", __func__); goto err; } - ret = dm_gpio_set_dir_flags(desc, flags | desc->flags); + ret = dm_gpio_set_dir_flags(desc, flags); if (ret) { debug("%s: dm_gpio_set_dir failed\n", __func__); goto err; @@ -1036,6 +1141,10 @@ static int gpio_post_bind(struct udevice *dev) ops->get_function += gd->reloc_off; if (ops->xlate) ops->xlate += gd->reloc_off; + if (ops->set_dir_flags) + ops->set_dir_flags += gd->reloc_off; + if (ops->get_dir_flags) + ops->get_dir_flags += gd->reloc_off; reloc_done++; } diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index 454578c8d2..c6991be1c9 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -117,10 +117,15 @@ struct udevice; struct gpio_desc { struct udevice *dev; /* Device, NULL for invalid GPIO */ unsigned long flags; + #define GPIOD_IS_OUT BIT(1) /* GPIO is an output */ #define GPIOD_IS_IN BIT(2) /* GPIO is an input */ #define GPIOD_ACTIVE_LOW BIT(3) /* value has active low */ #define GPIOD_IS_OUT_ACTIVE BIT(4) /* set output active */ +#define GPIOD_OPEN_DRAIN BIT(5) /* GPIO is open drain type */ +#define GPIOD_OPEN_SOURCE BIT(6) /* GPIO is open source type */ +#define GPIOD_PULL_UP BIT(7) /* GPIO has pull up enabled */ +#define GPIOD_PULL_DOWN BIT(8) /* GPIO has pull down enabled */ uint offset; /* GPIO offset within the device */ /* @@ -129,6 +134,12 @@ struct gpio_desc { */ }; +/* helper to compute the value of the gpio output */ +#define GPIOD_FLAGS_OUTPUT_MASK (GPIOD_ACTIVE_LOW | GPIOD_IS_OUT_ACTIVE) +#define GPIOD_FLAGS_OUTPUT(flags) \ + (((((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_IS_OUT_ACTIVE) || \ + (((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_ACTIVE_LOW)) ? 1 : 0) + /** * dm_gpio_is_valid() - Check if a GPIO is valid * @@ -253,6 +264,7 @@ struct dm_gpio_ops { int value); int (*get_value)(struct udevice *dev, unsigned offset); int (*set_value)(struct udevice *dev, unsigned offset, int value); + /** * get_function() Get the GPIO function * @@ -287,6 +299,37 @@ struct dm_gpio_ops { */ int (*xlate)(struct udevice *dev, struct gpio_desc *desc, struct ofnode_phandle_args *args); + + /** + * set_dir_flags() - Set GPIO dir flags + * + * This function should set up the GPIO configuration according to the + * information provide by the direction flags bitfield. + * + * This method is optional. + * + * @dev: GPIO device + * @offset: GPIO offset within that device + * @flags: GPIO configuration to use + * @return 0 if OK, -ve on error + */ + int (*set_dir_flags)(struct udevice *dev, unsigned int offset, + ulong flags); + + /** + * get_dir_flags() - Get GPIO dir flags + * + * This function return the GPIO direction flags used. + * + * This method is optional. + * + * @dev: GPIO device + * @offset: GPIO offset within that device + * @flags: place to put the used direction flags by GPIO + * @return 0 if OK, -ve on error + */ + int (*get_dir_flags)(struct udevice *dev, unsigned int offset, + ulong *flags); }; /** @@ -586,8 +629,7 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value); /** * dm_gpio_set_dir() - Set the direction for a GPIO * - * This sets up the direction according tot the provided flags. It will do - * nothing unless the direction is actually specified. + * This sets up the direction according to the GPIO flags: desc->flags. * * @desc: GPIO description containing device, offset and flags, * previously returned by gpio_request_by_name() @@ -596,11 +638,10 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value); int dm_gpio_set_dir(struct gpio_desc *desc); /** - * dm_gpio_set_dir_flags() - Set direction using specific flags + * dm_gpio_set_dir_flags() - Set direction using add flags * - * This is like dm_gpio_set_dir() except that the flags value is provided - * instead of being used from desc->flags. This is needed because in many - * cases the GPIO description does not include direction information. + * This sets up the direction according tot the provided flags and the GPIO + * description (desc->flags) which include direction information. * Note that desc->flags is updated by this function. * * @desc: GPIO description containing device, offset and flags, @@ -610,6 +651,18 @@ int dm_gpio_set_dir(struct gpio_desc *desc); */ int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags); +/** + * dm_gpio_get_dir_flags() - Get direction flags + * + * read the current direction flags + * + * @desc: GPIO description containing device, offset and flags, + * previously returned by gpio_request_by_name() + * @flags: place to put the used flags + * @return 0 if OK, -ve on error, in which case desc->flags is not updated + */ +int dm_gpio_get_dir_flags(struct gpio_desc *desc, ulong *flags); + /** * gpio_get_number() - Get the global GPIO number of a GPIO * -- 2.17.1