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])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;}@@ -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);@@ -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);@@ -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