[U-Boot] [PATCH v3] gpio: add gpio-hog support

add gpio-hog support. GPIO hogging is a mechanism providing automatic GPIO request and configuration as part of the gpio-controller's driver probe function.
for more infos see: doc/device-tree-bindings/gpio/gpio.txt
Signed-off-by: Heiko Schocher hs@denx.de
--- clean travis build, see result: https://travis-ci.org/hsdenx/u-boot-test/builds/538734780
Changes in v3: - probe now all gpio devices with gpio-hogs from board_r before board_late_init() call or if someone wants to access gpio-hog based gpios with gpio_hog_lookup_name() This is needed, because we cannot be sure, if a gpio device which contains gpio-hogs is probed. - add line-name property as Michal recommended - renamed gpio_priv_one into gpio_priv_one_hog and protected through CONFIG_DM_GPIO_HOG
Changes in v2: - move gpio_hog() call from post_probe() to post_bind() call. Check if current gpio device has gpio-hog definitions, if so, probe it.
common/board_r.c | 6 + doc/device-tree-bindings/gpio/gpio.txt | 55 +++++++ drivers/gpio/Kconfig | 10 ++ drivers/gpio/gpio-uclass.c | 217 ++++++++++++++++++++++--- include/asm-generic/gpio.h | 32 ++++ 5 files changed, 301 insertions(+), 19 deletions(-)
diff --git a/common/board_r.c b/common/board_r.c index 150e8cd424..507da4c74a 100644 --- a/common/board_r.c +++ b/common/board_r.c @@ -49,6 +49,9 @@ #include <linux/err.h> #include <efi_loader.h> #include <wdt.h> +#if defined(CONFIG_DM_GPIO_HOG) +#include <asm/gpio.h> +#endif
DECLARE_GLOBAL_DATA_PTR;
@@ -796,6 +799,9 @@ static init_fnc_t init_sequence_r[] = { #ifdef CONFIG_CMD_NET initr_ethaddr, #endif +#if defined(CONFIG_DM_GPIO_HOG) + gpio_hog_probe_all, +#endif #ifdef CONFIG_BOARD_LATE_INIT board_late_init, #endif diff --git a/doc/device-tree-bindings/gpio/gpio.txt b/doc/device-tree-bindings/gpio/gpio.txt index f7a158d858..e774439369 100644 --- a/doc/device-tree-bindings/gpio/gpio.txt +++ b/doc/device-tree-bindings/gpio/gpio.txt @@ -210,3 +210,58 @@ Example 2: Here, three GPIO ranges are defined wrt. two pin controllers. pinctrl1 GPIO ranges are defined using pin numbers whereas the GPIO ranges wrt. pinctrl2 are named "foo" and "bar". + +3) GPIO hog definitions +----------------------- + +The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism +providing automatic GPIO request and configuration as part of the +gpio-controller's driver probe function. + +Each GPIO hog definition is represented as a child node of the GPIO controller. +Required properties: +- gpio-hog: A property specifying that this child node represents a GPIO hog. +- gpios: Store the GPIO information (id, flags) for the GPIO to + affect. + + ! Not yet support more than one gpio ! + +Only one of the following properties scanned in the order shown below. +- input: A property specifying to set the GPIO direction as input. +- output-low A property specifying to set the GPIO direction as output with + the value low. +- output-high A property specifying to set the GPIO direction as output with + the value high. + +Optional properties: +- line-name: The GPIO label name. If not present the node name is used. + +Example: + + tca6416@20 { + compatible = "ti,tca6416"; + reg = <0x20>; + #gpio-cells = <2>; + gpio-controller; + + env_reset { + gpio-hog; + input; + gpios = <6 GPIO_ACTIVE_LOW>; + }; + boot_rescue { + gpio-hog; + input; + gpios = <7 GPIO_ACTIVE_LOW>; + }; + }; + +For the above Example you can than access the gpio in your boardcode +with: + + desc = gpio_hog_lookup_name("boot_rescue.gpio-hog"); + if (desc) { + if (dm_gpio_get_value(desc)) + printf("\nBooting into Rescue System\n"); + else + printf("\nBoot normal\n"); diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index e36a8abc42..fa1c99700f 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -14,6 +14,16 @@ config DM_GPIO particular GPIOs that they provide. The uclass interface is defined in include/asm-generic/gpio.h.
+config DM_GPIO_HOG + bool "Enable GPIO hog support" + depends on DM_GPIO + default n + help + Enable gpio hog support + The GPIO chip may contain GPIO hog definitions. GPIO hogging + is a mechanism providing automatic GPIO request and config- + uration as part of the gpio-controller's driver probe function. + config ALTERA_PIO bool "Altera PIO driver" depends on DM_GPIO diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index da5e9ba6e5..4ecff115f1 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -5,6 +5,7 @@
#include <common.h> #include <dm.h> +#include <dm/device-internal.h> #include <dt-bindings/gpio/gpio.h> #include <errno.h> #include <fdtdec.h> @@ -15,6 +16,18 @@
DECLARE_GLOBAL_DATA_PTR;
+#if defined(CONFIG_DM_GPIO_HOG) +struct gpio_priv_one_hog { + struct list_head list; + char *name; + struct gpio_desc gpiod; +}; + +static struct list_head hogs; +static int list_init; +static int gpio_hogs_probed; +#endif + /** * gpio_to_device() - Convert global GPIO number to device, number * @@ -141,6 +154,147 @@ static int gpio_find_and_xlate(struct gpio_desc *desc, return gpio_xlate_offs_flags(desc->dev, desc, args); }
+#if defined(CONFIG_DM_GPIO_HOG) +int gpio_hog_probe_all(void) +{ + struct udevice *dev; + ofnode node; + int ret; + + /* + * We need to probe all gpio-hog devices + * at some point, as we cannot be sure, + * that all gpio devices, which contain a + * gpio-hog definition are probed. + * + */ + if (gpio_hogs_probed) + return 0; + + for (uclass_first_device(UCLASS_GPIO, &dev); + dev; + uclass_next_device(&dev)) { + dev_for_each_subnode(node, dev) { + if (ofnode_read_bool(node, "gpio-hog")) { + ret = device_probe(dev); + if (ret) + return ret; + break; + } + } + } + gpio_hogs_probed = 1; + + return 0; +} + +struct gpio_desc *gpio_hog_lookup_name(const char *name) +{ + struct list_head *entry; + struct gpio_priv_one_hog *cur; + + /* be sure, all gpio devices with gpio-hogs are probed */ + gpio_hog_probe_all(); + list_for_each(entry, &hogs) { + cur = list_entry(entry, struct gpio_priv_one_hog, list); + if (strcmp(cur->name, name) == 0) + return &cur->gpiod; + } + + return NULL; +} + +static int gpio_hog(struct udevice *dev) +{ + ofnode node; + int found = 0; + int ret; + struct gpio_dev_priv *uc_priv = NULL; + + if (!list_init) { + INIT_LIST_HEAD(&hogs); + list_init = 1; + } + dev_for_each_subnode(node, dev) { + if (ofnode_read_bool(node, "gpio-hog")) { + found = 1; + break; + } + } + + if (!found) + return 0; + + uc_priv = dev_get_uclass_priv(dev); + if (!uc_priv) { + printf("%s: missing private data.\n", __func__); + return 0; + } + + /* scan for gpio-hog subnodes */ + dev_for_each_subnode(node, dev) { + u32 val[2]; + int value = 0; + int gpiod_flags; + struct gpio_priv_one_hog *new; + const char *nodename; + + if (!ofnode_read_bool(node, "gpio-hog")) + continue; + + if (ofnode_read_bool(node, "input")) { + gpiod_flags = GPIOD_IS_IN; + } else if (ofnode_read_bool(node, "output-high")) { + value = 1; + gpiod_flags = GPIOD_IS_OUT; + } else if (ofnode_read_bool(node, "output-low")) { + gpiod_flags = GPIOD_IS_OUT; + } else { + printf("%s: missing gpio-hog state.\n", __func__); + return -EINVAL; + } + + ret = ofnode_read_u32_array(node, "gpios", val, 2); + if (ret) { + printf("%s: wrong gpios property, 2 values needed, ret: %d\n", __func__, ret); + return ret; + } + + new = calloc(1, sizeof(struct gpio_priv_one_hog)); + nodename = ofnode_read_string(node, "line-name"); + if (!nodename) + nodename = ofnode_get_name(node); + ret = gpio_dev_request_index(dev, nodename, "gpio-hog", + val[0], gpiod_flags, val[1], + &new->gpiod); + if (ret < 0) { + debug("%s: node %s could not get gpio.\n", __func__, + ofnode_get_name(node)); + free(new); + return ret; + } + + new->name = uc_priv->name[new->gpiod.offset]; + list_add_tail(&new->list, &hogs); + dm_gpio_set_dir(&new->gpiod); + if (gpiod_flags == GPIOD_IS_OUT) + dm_gpio_set_value(&new->gpiod, value); + } + + return 0; +} +#else +static int gpio_hog(struct udevice *dev) +{ + return 0; +} + +struct gpio_desc *gpio_hog_lookup_name(const char *name) +{ + return NULL; +} +#endif + int dm_gpio_request(struct gpio_desc *desc, const char *label) { struct udevice *dev = desc->dev; @@ -149,8 +303,9 @@ int dm_gpio_request(struct gpio_desc *desc, const char *label) int ret;
uc_priv = dev_get_uclass_priv(dev); - if (uc_priv->name[desc->offset]) - return -EBUSY; + if (uc_priv) + if (uc_priv->name[desc->offset]) + return -EBUSY; str = strdup(label); if (!str) return -ENOMEM; @@ -640,22 +795,25 @@ int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count) return vector; }
-static int gpio_request_tail(int ret, ofnode node, +static int gpio_request_tail(int ret, const char *nodename, struct ofnode_phandle_args *args, const char *list_name, int index, - struct gpio_desc *desc, int flags, bool add_index) + struct gpio_desc *desc, int flags, + bool add_index, struct udevice *dev) { - desc->dev = NULL; + desc->dev = dev; desc->offset = 0; desc->flags = 0; if (ret) goto err;
- ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node, - &desc->dev); - if (ret) { - debug("%s: uclass_get_device_by_ofnode failed\n", __func__); - goto err; + if (!desc->dev) { + ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node, + &desc->dev); + if (ret) { + debug("%s: uclass_get_device_by_ofnode failed\n", __func__); + goto err; + } } ret = gpio_find_and_xlate(desc, args); if (ret) { @@ -663,8 +821,7 @@ static int gpio_request_tail(int ret, ofnode node, goto err; } ret = dm_gpio_requestf(desc, add_index ? "%s.%s%d" : "%s.%s", - ofnode_get_name(node), - list_name, index); + nodename, list_name, index); if (ret) { debug("%s: dm_gpio_requestf failed\n", __func__); goto err; @@ -678,7 +835,7 @@ static int gpio_request_tail(int ret, ofnode node, return 0; err: debug("%s: Node '%s', property '%s', failed to request GPIO index %d: %d\n", - __func__, ofnode_get_name(node), list_name, index, ret); + __func__, nodename, list_name, index, ret); return ret; }
@@ -692,8 +849,8 @@ static int _gpio_request_by_name_nodev(ofnode node, const char *list_name, ret = ofnode_parse_phandle_with_args(node, list_name, "#gpio-cells", 0, index, &args);
- return gpio_request_tail(ret, node, &args, list_name, index, desc, - flags, add_index); + return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name, + index, desc, flags, add_index, NULL); }
int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index, @@ -707,13 +864,14 @@ int gpio_request_by_name(struct udevice *dev, const char *list_name, int index, struct gpio_desc *desc, int flags) { struct ofnode_phandle_args args; + ofnode node; int ret;
ret = dev_read_phandle_with_args(dev, list_name, "#gpio-cells", 0, index, &args); - - return gpio_request_tail(ret, dev_ofnode(dev), &args, list_name, - index, desc, flags, index > 0); + node = dev_ofnode(dev); + return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name, + index, desc, flags, index > 0, NULL); }
int gpio_request_list_by_name_nodev(ofnode node, const char *list_name, @@ -832,12 +990,17 @@ int gpio_get_number(const struct gpio_desc *desc) static int gpio_post_probe(struct udevice *dev) { struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); + int ret;
uc_priv->name = calloc(uc_priv->gpio_count, sizeof(char *)); if (!uc_priv->name) return -ENOMEM;
- return gpio_renumber(NULL); + ret = gpio_renumber(NULL); + if (ret) + return ret; + + return gpio_hog(dev); }
static int gpio_pre_remove(struct udevice *dev) @@ -854,6 +1017,21 @@ static int gpio_pre_remove(struct udevice *dev) return gpio_renumber(dev); }
+int gpio_dev_request_index(struct udevice *dev, const char *nodename, + char *list_name, int index, int flags, + int dtflags, struct gpio_desc *desc) +{ + struct ofnode_phandle_args args; + + args.node = ofnode_null(); + args.args_count = 2; + args.args[0] = index; + args.args[1] = dtflags; + + return gpio_request_tail(0, nodename, &args, list_name, index, desc, + flags, 0, dev); +} + static int gpio_post_bind(struct udevice *dev) { #if defined(CONFIG_NEEDS_MANUAL_RELOC) @@ -885,6 +1063,7 @@ static int gpio_post_bind(struct udevice *dev) reloc_done++; } #endif + return 0; }
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index d03602696f..37f71e5708 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -348,6 +348,22 @@ const char *gpio_get_bank_info(struct udevice *dev, int *offset_count); */ int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc);
+/** + * gpio_hog_lookup_name() - Look up a named GPIO and return the gpio descr. + * + * @name: Name to look up + * @return: Returns gpio_desc for gpio + */ +struct gpio_desc *gpio_hog_lookup_name(const char *name); + +/** + * gpio_hog_probe_all() - probe all gpio devices with + * gpio-hog subnodes. + * + * @return: Returns return value from device_probe() + */ +int gpio_hog_probe_all(void); + /** * gpio_lookup_name - Look up a GPIO name and return its details * @@ -503,6 +519,22 @@ int gpio_request_list_by_name_nodev(ofnode node, const char *list_name, struct gpio_desc *desc_list, int max_count, int flags);
+/** + * gpio_dev_request_index() - request single GPIO from gpio device + * + * @dev: GPIO device + * @nodename: Name of node + * @list_name: Name of GPIO list (e.g. "board-id-gpios") + * @index: Index number of the GPIO in that list use request (0=first) + * @flags: GPIOD_* flags + * @dtflags: GPIO flags read from DT + * @desc: GPIO descriotor filled from this function + * @return: return value from gpio_request_tail() + */ +int gpio_dev_request_index(struct udevice *dev, const char *nodename, + char *list_name, int index, int flags, + int dtflags, struct gpio_desc *desc); + /** * dm_gpio_free() - Free a single GPIO *

Hi Heiko,
add gpio-hog support. GPIO hogging is a mechanism providing automatic GPIO request and configuration as part of the gpio-controller's driver probe function.
for more infos see: doc/device-tree-bindings/gpio/gpio.txt
Signed-off-by: Heiko Schocher hs@denx.de
It seens the hog function can be called several times, for gpio bank probed in pre-reloc phasis: - before recocation : gpio_post_probe() => gpio_hog() .... gpio_hogs_probed = 0 - after relocation : gpio_post_probe() => gpio_hog()... gpio_hogs_probed = 0 gpio_hog_probe_all() => gpio_post_probe() => gpio_hog()... gpio_hogs_probed = 1 I don't known if it is expected behavior: hog configuration 2 times in Uboot = before and after relocation
clean travis build, see result: https://travis-ci.org/hsdenx/u-boot-test/builds/538734780
Changes in v3:
- probe now all gpio devices with gpio-hogs from board_r before board_late_init() call or if someone wants to access gpio-hog based gpios with gpio_hog_lookup_name() This is needed, because we cannot be sure, if a gpio device which contains gpio-hogs is probed.
- add line-name property as Michal recommended
- renamed gpio_priv_one into gpio_priv_one_hog and protected through CONFIG_DM_GPIO_HOG
Changes in v2:
- move gpio_hog() call from post_probe() to post_bind() call. Check if current gpio device has gpio-hog definitions, if so, probe it.
common/board_r.c | 6 + doc/device-tree-bindings/gpio/gpio.txt | 55 +++++++ drivers/gpio/Kconfig | 10 ++ drivers/gpio/gpio-uclass.c | 217 ++++++++++++++++++++++--- include/asm-generic/gpio.h | 32 ++++ 5 files changed, 301 insertions(+), 19 deletions(-)
diff --git a/common/board_r.c b/common/board_r.c index 150e8cd424..507da4c74a 100644 --- a/common/board_r.c +++ b/common/board_r.c @@ -49,6 +49,9 @@ #include <linux/err.h> #include <efi_loader.h> #include <wdt.h> +#if defined(CONFIG_DM_GPIO_HOG) +#include <asm/gpio.h> +#endif
DECLARE_GLOBAL_DATA_PTR;
@@ -796,6 +799,9 @@ static init_fnc_t init_sequence_r[] = { #ifdef CONFIG_CMD_NET initr_ethaddr, #endif +#if defined(CONFIG_DM_GPIO_HOG)
- gpio_hog_probe_all,
+#endif #ifdef CONFIG_BOARD_LATE_INIT board_late_init, #endif diff --git a/doc/device-tree-bindings/gpio/gpio.txt b/doc/device-tree- bindings/gpio/gpio.txt index f7a158d858..e774439369 100644 --- a/doc/device-tree-bindings/gpio/gpio.txt +++ b/doc/device-tree-bindings/gpio/gpio.txt @@ -210,3 +210,58 @@ Example 2: Here, three GPIO ranges are defined wrt. two pin controllers. pinctrl1 GPIO ranges are defined using pin numbers whereas the GPIO ranges wrt. pinctrl2 are named "foo" and "bar".
+3) GPIO hog definitions +-----------------------
+The GPIO chip may contain GPIO hog definitions. GPIO hogging is a +mechanism providing automatic GPIO request and configuration as part of +the gpio-controller's driver probe function.
+Each GPIO hog definition is represented as a child node of the GPIO controller. +Required properties: +- gpio-hog: A property specifying that this child node represents a GPIO hog. +- gpios: Store the GPIO information (id, flags) for the GPIO to
affect.
! Not yet support more than one gpio !
+Only one of the following properties scanned in the order shown below. +- input: A property specifying to set the GPIO direction as input. +- output-low A property specifying to set the GPIO direction as output with
the value low.
+- output-high A property specifying to set the GPIO direction as output with
the value high.
+Optional properties: +- line-name: The GPIO label name. If not present the node name is used.
+Example:
tca6416@20 {
compatible = "ti,tca6416";
reg = <0x20>;
#gpio-cells = <2>;
gpio-controller;
env_reset {
gpio-hog;
input;
gpios = <6 GPIO_ACTIVE_LOW>;
};
boot_rescue {
gpio-hog;
input;
gpios = <7 GPIO_ACTIVE_LOW>;
};
};
+For the above Example you can than access the gpio in your boardcode +with:
desc = gpio_hog_lookup_name("boot_rescue.gpio-hog");
if (desc) {
if (dm_gpio_get_value(desc))
printf("\nBooting into Rescue System\n");
else
printf("\nBoot normal\n");
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index e36a8abc42..fa1c99700f 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -14,6 +14,16 @@ config DM_GPIO particular GPIOs that they provide. The uclass interface is defined in include/asm-generic/gpio.h.
+config DM_GPIO_HOG
- bool "Enable GPIO hog support"
- depends on DM_GPIO
- default n
- help
Enable gpio hog support
The GPIO chip may contain GPIO hog definitions. GPIO hogging
is a mechanism providing automatic GPIO request and config-
uration as part of the gpio-controller's driver probe function.
config ALTERA_PIO bool "Altera PIO driver" depends on DM_GPIO diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index da5e9ba6e5..4ecff115f1 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -5,6 +5,7 @@
#include <common.h> #include <dm.h> +#include <dm/device-internal.h> #include <dt-bindings/gpio/gpio.h> #include <errno.h> #include <fdtdec.h> @@ -15,6 +16,18 @@
DECLARE_GLOBAL_DATA_PTR;
+#if defined(CONFIG_DM_GPIO_HOG) +struct gpio_priv_one_hog {
- struct list_head list;
- char *name;
- struct gpio_desc gpiod;
+};
+static struct list_head hogs; +static int list_init; +static int gpio_hogs_probed; +#endif
/**
- gpio_to_device() - Convert global GPIO number to device, number
@@ -141,6 +154,147 @@ static int gpio_find_and_xlate(struct gpio_desc *desc, return gpio_xlate_offs_flags(desc->dev, desc, args); }
+#if defined(CONFIG_DM_GPIO_HOG) +int gpio_hog_probe_all(void) +{
- struct udevice *dev;
- ofnode node;
- int ret;
- /*
* We need to probe all gpio-hog devices
* at some point, as we cannot be sure,
* that all gpio devices, which contain a
* gpio-hog definition are probed.
*
*/
- if (gpio_hogs_probed)
return 0;
- for (uclass_first_device(UCLASS_GPIO, &dev);
dev;
uclass_next_device(&dev)) {
uclass_next_device automatically call probe for the class (in uclass_get_device_tail) in this context, I think that uclass_find_next_device is better
dev_for_each_subnode(node, dev) {
if (ofnode_read_bool(node, "gpio-hog")) {
ret = device_probe(dev);
if (ret)
return ret;
break;
}
}
- }
- gpio_hogs_probed = 1;
- return 0;
+}
+struct gpio_desc *gpio_hog_lookup_name(const char *name) {
- struct list_head *entry;
- struct gpio_priv_one_hog *cur;
- /* be sure, all gpio devices with gpio-hogs are probed */
- gpio_hog_probe_all();
- list_for_each(entry, &hogs) {
cur = list_entry(entry, struct gpio_priv_one_hog, list);
if (strcmp(cur->name, name) == 0)
return &cur->gpiod;
- }
- return NULL;
+}
+static int gpio_hog(struct udevice *dev) {
- ofnode node;
- int found = 0;
- int ret;
- struct gpio_dev_priv *uc_priv = NULL;
- if (!list_init) {
INIT_LIST_HEAD(&hogs);
list_init = 1;
- }
- dev_for_each_subnode(node, dev) {
if (ofnode_read_bool(node, "gpio-hog")) {
found = 1;
break;
}
- }
This check is really needed, as it is already done in the main loop ? I think you can remove this first 'found' loop.
- if (!found)
return 0;
- uc_priv = dev_get_uclass_priv(dev);
- if (!uc_priv) {
printf("%s: missing private data.\n", __func__);
return 0;
- }
It is prossible to have uc_priv = 0 ? by construction, is is not allowed in driver mode, so this test can be remove I think.
- /* scan for gpio-hog subnodes */
- dev_for_each_subnode(node, dev) {
u32 val[2];
int value = 0;
int gpiod_flags;
struct gpio_priv_one_hog *new;
const char *nodename;
if (!ofnode_read_bool(node, "gpio-hog"))
continue;
if (ofnode_read_bool(node, "input")) {
gpiod_flags = GPIOD_IS_IN;
} else if (ofnode_read_bool(node, "output-high")) {
value = 1;
gpiod_flags = GPIOD_IS_OUT;
} else if (ofnode_read_bool(node, "output-low")) {
gpiod_flags = GPIOD_IS_OUT;
} else {
printf("%s: missing gpio-hog state.\n", __func__);
return -EINVAL;
}
ret = ofnode_read_u32_array(node, "gpios", val, 2);
if (ret) {
printf("%s: wrong gpios property, 2 values needed, ret:
%d\n", __func__, ret);
return ret;
}
new = calloc(1, sizeof(struct gpio_priv_one_hog));
nodename = ofnode_read_string(node, "line-name");
if (!nodename)
nodename = ofnode_get_name(node);
ret = gpio_dev_request_index(dev, nodename, "gpio-hog",
val[0], gpiod_flags, val[1],
&new->gpiod);
if (ret < 0) {
debug("%s: node %s could not get gpio.\n", __func__,
ofnode_get_name(node));
free(new);
return ret;
}
new->name = uc_priv->name[new->gpiod.offset];
list_add_tail(&new->list, &hogs);
dm_gpio_set_dir(&new->gpiod);
if (gpiod_flags == GPIOD_IS_OUT)
dm_gpio_set_value(&new->gpiod, value);
- }
- return 0;
+} +#else +static int gpio_hog(struct udevice *dev) {
- return 0;
+}
+struct gpio_desc *gpio_hog_lookup_name(const char *name) {
- return NULL;
+} +#endif
int dm_gpio_request(struct gpio_desc *desc, const char *label) { struct udevice *dev = desc->dev; @@ -149,8 +303,9 @@ int dm_gpio_request(struct gpio_desc *desc, const char *label) int ret;
uc_priv = dev_get_uclass_priv(dev);
- if (uc_priv->name[desc->offset])
return -EBUSY;
- if (uc_priv)
if (uc_priv->name[desc->offset])
str = strdup(label); if (!str) return -ENOMEM;return -EBUSY;
@@ -640,22 +795,25 @@ int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count) return vector; }
-static int gpio_request_tail(int ret, ofnode node, +static int gpio_request_tail(int ret, const char *nodename, struct ofnode_phandle_args *args, const char *list_name, int index,
struct gpio_desc *desc, int flags, bool add_index)
struct gpio_desc *desc, int flags,
bool add_index, struct udevice *dev)
{
- desc->dev = NULL;
- desc->dev = dev; desc->offset = 0; desc->flags = 0; if (ret) goto err;
- ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node,
&desc->dev);
- if (ret) {
debug("%s: uclass_get_device_by_ofnode failed\n", __func__);
goto err;
- if (!desc->dev) {
ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node,
&desc->dev);
if (ret) {
debug("%s: uclass_get_device_by_ofnode failed\n",
__func__);
goto err;
} ret = gpio_find_and_xlate(desc, args); if (ret) {}
@@ -663,8 +821,7 @@ static int gpio_request_tail(int ret, ofnode node, goto err; } ret = dm_gpio_requestf(desc, add_index ? "%s.%s%d" : "%s.%s",
ofnode_get_name(node),
list_name, index);
if (ret) { debug("%s: dm_gpio_requestf failed\n", __func__); goto err;nodename, list_name, index);
@@ -678,7 +835,7 @@ static int gpio_request_tail(int ret, ofnode node, return 0; err: debug("%s: Node '%s', property '%s', failed to request GPIO index %d: %d\n",
__func__, ofnode_get_name(node), list_name, index, ret);
return ret;__func__, nodename, list_name, index, ret);
}
@@ -692,8 +849,8 @@ static int _gpio_request_by_name_nodev(ofnode node, const char *list_name, ret = ofnode_parse_phandle_with_args(node, list_name, "#gpio-cells", 0, index, &args);
- return gpio_request_tail(ret, node, &args, list_name, index, desc,
flags, add_index);
- return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name,
index, desc, flags, add_index, NULL);
}
int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index, @@ -707,13 +864,14 @@ int gpio_request_by_name(struct udevice *dev, const char *list_name, int index, struct gpio_desc *desc, int flags) { struct ofnode_phandle_args args;
ofnode node; int ret;
ret = dev_read_phandle_with_args(dev, list_name, "#gpio-cells", 0, index, &args);
- return gpio_request_tail(ret, dev_ofnode(dev), &args, list_name,
index, desc, flags, index > 0);
- node = dev_ofnode(dev);
- return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name,
index, desc, flags, index > 0, NULL);
}
int gpio_request_list_by_name_nodev(ofnode node, const char *list_name, @@ - 832,12 +990,17 @@ int gpio_get_number(const struct gpio_desc *desc) static int gpio_post_probe(struct udevice *dev) { struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
int ret;
uc_priv->name = calloc(uc_priv->gpio_count, sizeof(char *)); if (!uc_priv->name) return -ENOMEM;
- return gpio_renumber(NULL);
- ret = gpio_renumber(NULL);
- if (ret)
return ret;
It is strange for me to have many device tree parsing in probe function....
For me => hog detection + DT parsing in gpio_post_bind() .... info saved in platdata => gpio configuration for hog (request and set_dir) => probe function
- return gpio_hog(dev);
}
One other solution to do it is to manage a hog with uclass (using the new UCLASS_NOP or misc for example) http://patchwork.ozlabs.org/patch/1098913/ Ps: we can also create a new UCLASS_GPIOHOG
And we to bind this class during GPIO binding; the parsing of DT is done only one time and manage privdata and platdata as expected by driver model....
For example something like (not tested)
static int gpio_post_bind(struct udevice *dev) { struct udevice *child; ofnode node; .....
#if defined(CONFIG_DM_GPIO_HOG) dev_for_each_subnode(node, dev) { if (ofnode_read_bool(node, "gpio-hog")) { const char *name = fdt_get_name(fdt, node, NULL); device_bind_driver_to_node (dev, "gpio_hog", name, dev_ofnode(dev), &child); } } #endif return 0; }
#if defined(CONFIG_DM_GPIO_HOG)
struct gpio_hog_priv{ struct gpio_desc gpiod; }
struct gpio_hog_data { int gpiod_flags; int value; u32 val[2]; }
static int gpio_hog_ofdata_to_platdata(struct udevice *dev) { struct gpio_hog_data *plat = dev_get_platdata(dev); char *nodename;
plat->value = 0; if (dev_read_bool(dev, "input")) { plat->gpiod_flags = GPIOD_IS_IN; } else if (dev_read_bool(dev, "output-high")) { plat->value = 1; gpiod_flags = GPIOD_IS_OUT; } else if (dev_read_bool(dev, "output-low")) { gpiod_flags = GPIOD_IS_OUT; } else { printf("%s: missing gpio-hog state.\n", __func__); return -EINVAL; } ret = dev_read_u32_array(dev, "gpios", plat->val, 2); if (ret) { printf("%s: wrong gpios property, 2 values needed, ret: %d\n", __func__, ret); return ret; } nodename = dev_read_string(node, "line-name"); if (!nodename) nodename = dev_read_name(node); device_set_name(dev, nodename); }
static int gpio_hog_probe(struct udevice *dev) { struct gpio_hog_data *plat = dev_get_platdata(dev); struct gpio_hog_priv *priv = dev_get_privdata(dev);
ret = gpio_dev_request_index(dev, dev->name, "gpio-hog", plat->val[0], plat->gpiod_flags, plat->val[1], &priv->gpiod); if (ret < 0) { debug("%s: node %s could not get gpio.\n", __func__, ofnode_get_name(node)); return ret; } dm_gpio_set_dir_flags(&priv->gpiod); if (gpiod_flags == GPIOD_IS_OUT) dm_gpio_set_value(&priv->gpiod, plat->value); }
int gpio_hog_probe_all(void) { struct udevice *dev; ofnode node;
for (uclass_first_device(UCLASS_NOP, &dev); dev; uclass_find_next_device (&dev)) { if (dev->driver == M_GET_DRIVER(gpio_hog)) { ret = device_probe(dev); if (ret) ' return ret; break; } } } }
struct gpio_desc *gpio_hog_lookup_name(const char *name) { struct udevice *dev;
/* be sure, all gpio devices with gpio-hogs are probed */ gpio_hog_probe_all(); if (!uclass_get_device_by_name(UCLASS_NOP, name, &dev)) ' struct gpio_hog_priv *priv = dev_get_privdata(dev); return &priv->gpiod; }
return NULL; }
U_BOOT_DRIVER(gio_hog) = { .name = "gpio_hog", .id = UCLASS_NOP, .ofdata_to_platdata = gpio_hog_ofdata_to_platdata, .probe = gpio_hog_probe, .priv_auto_alloc_size = sizeof(struct gpio_hog_priv), .platdata_auto_alloc_size = sizeof(struct gpio_hog_data), } #endif
static int gpio_pre_remove(struct udevice *dev) @@ -854,6 +1017,21 @@ static int gpio_pre_remove(struct udevice *dev) return gpio_renumber(dev); }
+int gpio_dev_request_index(struct udevice *dev, const char *nodename,
char *list_name, int index, int flags,
int dtflags, struct gpio_desc *desc) {
- struct ofnode_phandle_args args;
- args.node = ofnode_null();
- args.args_count = 2;
- args.args[0] = index;
- args.args[1] = dtflags;
- return gpio_request_tail(0, nodename, &args, list_name, index, desc,
flags, 0, dev);
+}
static int gpio_post_bind(struct udevice *dev) { #if defined(CONFIG_NEEDS_MANUAL_RELOC) @@ -885,6 +1063,7 @@ static int gpio_post_bind(struct udevice *dev) reloc_done++; } #endif
- return 0;
}
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index d03602696f..37f71e5708 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -348,6 +348,22 @@ const char *gpio_get_bank_info(struct udevice *dev, int *offset_count); */ int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc);
+/**
- gpio_hog_lookup_name() - Look up a named GPIO and return the gpio descr.
- @name: Name to look up
- @return: Returns gpio_desc for gpio
- */
+struct gpio_desc *gpio_hog_lookup_name(const char *name);
+/**
- gpio_hog_probe_all() - probe all gpio devices with
- gpio-hog subnodes.
- @return: Returns return value from device_probe()
- */
+int gpio_hog_probe_all(void);
/**
- gpio_lookup_name - Look up a GPIO name and return its details
@@ -503,6 +519,22 @@ int gpio_request_list_by_name_nodev(ofnode node, const char *list_name, struct gpio_desc *desc_list, int max_count, int flags);
+/**
- gpio_dev_request_index() - request single GPIO from gpio device
- @dev: GPIO device
- @nodename: Name of node
- @list_name: Name of GPIO list (e.g. "board-id-gpios")
- @index: Index number of the GPIO in that list use request (0=first)
- @flags: GPIOD_* flags
- @dtflags: GPIO flags read from DT
- @desc: GPIO descriotor filled from this function
- @return: return value from gpio_request_tail()
- */
+int gpio_dev_request_index(struct udevice *dev, const char *nodename,
char *list_name, int index, int flags,
int dtflags, struct gpio_desc *desc);
/**
- dm_gpio_free() - Free a single GPIO
-- 2.21.0
Regards
Patrick

Hello Patrick,
Am 04.06.2019 um 13:49 schrieb Patrick DELAUNAY:
Hi Heiko,
add gpio-hog support. GPIO hogging is a mechanism providing automatic GPIO request and configuration as part of the gpio-controller's driver probe function.
for more infos see: doc/device-tree-bindings/gpio/gpio.txt
Signed-off-by: Heiko Schocher hs@denx.de
It seens the hog function can be called several times, for gpio bank probed in pre-reloc phasis:
- before recocation : gpio_post_probe() => gpio_hog() .... gpio_hogs_probed = 0
- after relocation : gpio_post_probe() => gpio_hog()... gpio_hogs_probed = 0 gpio_hog_probe_all() => gpio_post_probe() => gpio_hog()... gpio_hogs_probed = 1
I don't known if it is expected behavior: hog configuration 2 times in Uboot = before and after relocation
No, not expected.
clean travis build, see result: https://travis-ci.org/hsdenx/u-boot-test/builds/538734780
Changes in v3:
- probe now all gpio devices with gpio-hogs from board_r before board_late_init() call or if someone wants to access gpio-hog based gpios with gpio_hog_lookup_name() This is needed, because we cannot be sure, if a gpio device which contains gpio-hogs is probed.
- add line-name property as Michal recommended
- renamed gpio_priv_one into gpio_priv_one_hog and protected through CONFIG_DM_GPIO_HOG
Changes in v2:
move gpio_hog() call from post_probe() to post_bind() call. Check if current gpio device has gpio-hog definitions, if so, probe it.
common/board_r.c | 6 + doc/device-tree-bindings/gpio/gpio.txt | 55 +++++++ drivers/gpio/Kconfig | 10 ++ drivers/gpio/gpio-uclass.c | 217 ++++++++++++++++++++++--- include/asm-generic/gpio.h | 32 ++++ 5 files changed, 301 insertions(+), 19 deletions(-)
[...]
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index da5e9ba6e5..4ecff115f1 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -5,6 +5,7 @@
#include <common.h> #include <dm.h> +#include <dm/device-internal.h> #include <dt-bindings/gpio/gpio.h> #include <errno.h> #include <fdtdec.h> @@ -15,6 +16,18 @@
DECLARE_GLOBAL_DATA_PTR;
+#if defined(CONFIG_DM_GPIO_HOG) +struct gpio_priv_one_hog {
- struct list_head list;
- char *name;
- struct gpio_desc gpiod;
+};
+static struct list_head hogs; +static int list_init; +static int gpio_hogs_probed; +#endif
- /**
- gpio_to_device() - Convert global GPIO number to device, number
@@ -141,6 +154,147 @@ static int gpio_find_and_xlate(struct gpio_desc *desc, return gpio_xlate_offs_flags(desc->dev, desc, args); }
+#if defined(CONFIG_DM_GPIO_HOG) +int gpio_hog_probe_all(void) +{
- struct udevice *dev;
- ofnode node;
- int ret;
- /*
* We need to probe all gpio-hog devices
* at some point, as we cannot be sure,
* that all gpio devices, which contain a
* gpio-hog definition are probed.
*
*/
- if (gpio_hogs_probed)
return 0;
- for (uclass_first_device(UCLASS_GPIO, &dev);
dev;
uclass_next_device(&dev)) {
uclass_next_device automatically call probe for the class (in uclass_get_device_tail) in this context, I think that uclass_find_next_device is better
The idea was to only probe gpio devices with gpio-hog subnodes...
dev_for_each_subnode(node, dev) {
if (ofnode_read_bool(node, "gpio-hog")) {
ret = device_probe(dev);
if (ret)
return ret;
break;
}
}
- }
- gpio_hogs_probed = 1;
- return 0;
+}
+struct gpio_desc *gpio_hog_lookup_name(const char *name) {
- struct list_head *entry;
- struct gpio_priv_one_hog *cur;
- /* be sure, all gpio devices with gpio-hogs are probed */
- gpio_hog_probe_all();
- list_for_each(entry, &hogs) {
cur = list_entry(entry, struct gpio_priv_one_hog, list);
if (strcmp(cur->name, name) == 0)
return &cur->gpiod;
- }
- return NULL;
+}
+static int gpio_hog(struct udevice *dev) {
- ofnode node;
- int found = 0;
- int ret;
- struct gpio_dev_priv *uc_priv = NULL;
- if (!list_init) {
INIT_LIST_HEAD(&hogs);
list_init = 1;
- }
- dev_for_each_subnode(node, dev) {
if (ofnode_read_bool(node, "gpio-hog")) {
found = 1;
break;
}
- }
This check is really needed, as it is already done in the main loop ? I think you can remove this first 'found' loop.
Yes if we only setup the gpio-hogs from main loop.
- if (!found)
return 0;
- uc_priv = dev_get_uclass_priv(dev);
- if (!uc_priv) {
printf("%s: missing private data.\n", __func__);
return 0;
- }
It is prossible to have uc_priv = 0 ? by construction, is is not allowed in driver mode, so this test can be remove I think.
Yes, just panic check. I remove this.
- /* scan for gpio-hog subnodes */
- dev_for_each_subnode(node, dev) {
u32 val[2];
int value = 0;
int gpiod_flags;
struct gpio_priv_one_hog *new;
const char *nodename;
if (!ofnode_read_bool(node, "gpio-hog"))
continue;
if (ofnode_read_bool(node, "input")) {
gpiod_flags = GPIOD_IS_IN;
} else if (ofnode_read_bool(node, "output-high")) {
value = 1;
gpiod_flags = GPIOD_IS_OUT;
} else if (ofnode_read_bool(node, "output-low")) {
gpiod_flags = GPIOD_IS_OUT;
} else {
printf("%s: missing gpio-hog state.\n", __func__);
return -EINVAL;
}
ret = ofnode_read_u32_array(node, "gpios", val, 2);
if (ret) {
printf("%s: wrong gpios property, 2 values needed, ret:
%d\n", __func__, ret);
return ret;
}
new = calloc(1, sizeof(struct gpio_priv_one_hog));
nodename = ofnode_read_string(node, "line-name");
if (!nodename)
nodename = ofnode_get_name(node);
ret = gpio_dev_request_index(dev, nodename, "gpio-hog",
val[0], gpiod_flags, val[1],
&new->gpiod);
if (ret < 0) {
debug("%s: node %s could not get gpio.\n", __func__,
ofnode_get_name(node));
free(new);
return ret;
}
new->name = uc_priv->name[new->gpiod.offset];
list_add_tail(&new->list, &hogs);
dm_gpio_set_dir(&new->gpiod);
if (gpiod_flags == GPIOD_IS_OUT)
dm_gpio_set_value(&new->gpiod, value);
- }
- return 0;
+} +#else +static int gpio_hog(struct udevice *dev) {
- return 0;
+}
+struct gpio_desc *gpio_hog_lookup_name(const char *name) {
- return NULL;
+} +#endif
- int dm_gpio_request(struct gpio_desc *desc, const char *label) { struct udevice *dev = desc->dev;
@@ -149,8 +303,9 @@ int dm_gpio_request(struct gpio_desc *desc, const char *label) int ret;
uc_priv = dev_get_uclass_priv(dev);
- if (uc_priv->name[desc->offset])
return -EBUSY;
- if (uc_priv)
if (uc_priv->name[desc->offset])
str = strdup(label); if (!str) return -ENOMEM;return -EBUSY;
@@ -640,22 +795,25 @@ int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count) return vector; }
-static int gpio_request_tail(int ret, ofnode node, +static int gpio_request_tail(int ret, const char *nodename, struct ofnode_phandle_args *args, const char *list_name, int index,
struct gpio_desc *desc, int flags, bool add_index)
struct gpio_desc *desc, int flags,
{bool add_index, struct udevice *dev)
- desc->dev = NULL;
- desc->dev = dev; desc->offset = 0; desc->flags = 0; if (ret) goto err;
- ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node,
&desc->dev);
- if (ret) {
debug("%s: uclass_get_device_by_ofnode failed\n", __func__);
goto err;
- if (!desc->dev) {
ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node,
&desc->dev);
if (ret) {
debug("%s: uclass_get_device_by_ofnode failed\n",
__func__);
goto err;
} ret = gpio_find_and_xlate(desc, args); if (ret) {}
@@ -663,8 +821,7 @@ static int gpio_request_tail(int ret, ofnode node, goto err; } ret = dm_gpio_requestf(desc, add_index ? "%s.%s%d" : "%s.%s",
ofnode_get_name(node),
list_name, index);
if (ret) { debug("%s: dm_gpio_requestf failed\n", __func__); goto err;nodename, list_name, index);
@@ -678,7 +835,7 @@ static int gpio_request_tail(int ret, ofnode node, return 0; err: debug("%s: Node '%s', property '%s', failed to request GPIO index %d: %d\n",
__func__, ofnode_get_name(node), list_name, index, ret);
return ret; }__func__, nodename, list_name, index, ret);
@@ -692,8 +849,8 @@ static int _gpio_request_by_name_nodev(ofnode node, const char *list_name, ret = ofnode_parse_phandle_with_args(node, list_name, "#gpio-cells", 0, index, &args);
- return gpio_request_tail(ret, node, &args, list_name, index, desc,
flags, add_index);
return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name,
index, desc, flags, add_index, NULL);
}
int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index,
@@ -707,13 +864,14 @@ int gpio_request_by_name(struct udevice *dev, const char *list_name, int index, struct gpio_desc *desc, int flags) { struct ofnode_phandle_args args;
ofnode node; int ret;
ret = dev_read_phandle_with_args(dev, list_name, "#gpio-cells", 0, index, &args);
- return gpio_request_tail(ret, dev_ofnode(dev), &args, list_name,
index, desc, flags, index > 0);
node = dev_ofnode(dev);
return gpio_request_tail(ret, ofnode_get_name(node), &args, list_name,
index, desc, flags, index > 0, NULL);
}
int gpio_request_list_by_name_nodev(ofnode node, const char *list_name, @@ -
832,12 +990,17 @@ int gpio_get_number(const struct gpio_desc *desc) static int gpio_post_probe(struct udevice *dev) { struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
int ret;
uc_priv->name = calloc(uc_priv->gpio_count, sizeof(char *)); if (!uc_priv->name) return -ENOMEM;
- return gpio_renumber(NULL);
- ret = gpio_renumber(NULL);
- if (ret)
return ret;
It is strange for me to have many device tree parsing in probe function....
For me => hog detection + DT parsing in gpio_post_bind() .... info saved in platdata => gpio configuration for hog (request and set_dir) => probe function
Yes, this approach is much more cleaner.
- return gpio_hog(dev); }
One other solution to do it is to manage a hog with uclass (using the new UCLASS_NOP or misc for example) http://patchwork.ozlabs.org/patch/1098913/
Ah, thanks for this hint, wasn;t aware of it.
Ps: we can also create a new UCLASS_GPIOHOG
Heh, I had a version (never posted) with such an approach. Thought this is to much overhead ... I try first with UCLASS_NOP.
And we to bind this class during GPIO binding; the parsing of DT is done only one time and manage privdata and platdata as expected by driver model....
Yes, cleaner.
For example something like (not tested)
[...]
Thanks for your input! I try to rework this soon.
bye, Heiko
participants (2)
-
Heiko Schocher
-
Patrick DELAUNAY